ABSTRACT

A SERIES OF PROPOSED
LABORATORYVEXERCISES

By
John Charles Dargis

Seven laboratory proposals are presented which deal
with subject material pertinent to the field of packaging.
Proposal one concerns itself with the presentation of some
of the basic parameters of statistics including concepts
of central location, standard deviation, t-test and statis-
tical analysis. The theories behind and characteristics of
stress-strain analysis of packaging materials is the subject
of proposal two. Pr0posal three deals with packaging mate-
rials as a barrier against water vapor transmission_and the
construction of isotherm moisture content curves. The
bursting test, edge crush, flat crush and tOp to bottom
compression strength encompass the physical testing of
corrugated paperboard in providing the basis for preposal
four. Proposal five presents the qualities and physical
test values of recycled paper. Qualitative values are
compared in the making of recycled paper while varying
ratios of recycled to virgin fiber constitutions of paper are

brought out through several physical tests including

John Charles Dargis
bursting strength, stiffness, tearing resistance and tensile
strength. The materials and construction of three common
plastic packages--the skin, blister and shrink packages--are
examined in prOposal six. The basic gas laws and their
application to the aerosol package system comprise the

contents of preposal seven.

A SERIES OF PROPOSED
LABORATORY EXERCISES

By
John Charles Dargis

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

School of Packaging

1974

DEDICATED TO
MY PARENTS FOR THEIR UNFAOLTERING AND UNQUESTIONING SUPPORT

ii

ACKNOWLEDGMENTS

I would like to extend my appreciation to Dr. James
Goff, Professor Istvan Gyeszli, Professor Gunilla Jonson and
Professor Richard Nicholas for their kind assistance. I owe
particular adulation to Professor Wayne Clifford who, as my
major professor, provided me with more than enough heuristic
direction, encouragement and patience to see me through this
thesis. Also, a battery of personal friends contributed
perspicacious suggestions and support I could not have done
without. Among them I would like to mention Steve Bakus,
Barbara Brown, Carla Canfield, Dan Goodwin, Fran Kinson,

Debbie McFann and Doug Novakoski.

iii

INTRODUCTION

PROPOSAL
PROPOSAL
PROPOSAL
PROPOSAL
PROPOSAL
PROPOSAL
PROPOSAL
APPENDIX
APPENDIX
APPENDIX

1:

(fl-#04

nw>xxo~

TABLE OF CONTENTS

STATISTICS .

STRESS-STRAIN ANALYSIS . . . . . .
WATER VAPOR TRANSMISSION .
CORRUGATED PAPERBOARD TESTING . .
PAPER AND RECYCLING . . . .

PLASTIC PACKAGES . . . . . . .
AEROSOLS .

ATTITUDE SURVEY

SAMPLE STATISTICS PROBLEMS . . . . .

OPERATING INSTRUCTIONS FOR THE INSTRON
TESTING MACHINE . . . . . .

LIST OF REFERENCES . . . . . . . . . . . . . .

iv

13
19
27
36

. 43

$1
59
64

66
74

LIST OF TABLES

Table
1. Various Raw Materials at Different Beating Times . . 38

2. Question Number Followed By Accumulative Response
Order. . . . . . . . . . . . . . . . . . . . . . . . 62

Figure

LIST OF FIGURES

Control Panel (SST-77)
Recorder Mechanism .
Crosshead Mechanism
Crosshead Gear Ratios
Crosshead Door Switch

Recorder Gear Shafts

vi

47
7O
71
72
73
73

INTRODUCTION

Packaging laboratories have come under the scrutiny
of both faculty and students. Although Opinions have varied
from person to person and from time to time, it is generally
held by all that packaging laboratories should reflect the
conditions and needs of the industrial world (with which the
school of packaging so closely associates) as well as the
interests of students and faculty. It may even be implied
that the medley of labs existing in packaging now could even-
tually be superseded by industrially oriented, initiated and
sponsored work-study arrangements. Since the realization of
such arrangements is some distance away, this thesis is but
a step in that direction by prOposing revisions and additions
to what exists now.

The packaging laboratory prOposals were compiled from
a variety of interest and informational inputs. As a teaching
assistant, the author became aware of the Shortcomings of
packaging labs through both his own observations and feedback
from students who he instructed in lab over the terms.
COUpling many conversations with faculty members in packaging
and the author's own research into literature reflecting the
current movements of industry pertaining to packaging, this

thesis was able to take substantive form.

2

The roots of many of the following prOposals stem
from Packaging 422 Lab, Packaging 321, and it's precursor--
the old Packaging 320 Lab. In essence, the proposals are
limited primarily to materials and material testing, but
contain many branching implications for further didactic
laboratory situations. To enhance the evaluative input of
students concerning these labs, an attempt was made to obtain
objective data from them by means of an attitude survey. The
details of this survey may be found in Appendix A.

Students have experienced confusion over ASTM Stan-
dards, how they came about, and just how they are intended to
be used in packaging. Many of the following proposed exer-
cises will incorporate reference to or in some way employ the
use of ASTM Standards.

The American Society for Testing and Materials is an
international nonprofit, technical, scientific, and educa-
tional society which has developed more than 4,700 standard
Specifications for the methods of testing materials-(1973
ASTM1 figures). The mainstream of activity flows through
more than 115 main technical committees which insure a
balanced representation among producers, consumers, and
general interest groups, i.e., universities and independent
laboratories. There are some 33 volumes, reviewed or revised
each year, covering specifications and test standards for
materials such as paper, leather, steel, and cellular plas-
tics, to name a few.

The use of ASTM Standards is purely voluntary. In

3

fact, cases do arise where the use of ASTM Standards are
more restrictive than needed. Usually a new test procedure,
or the modification of an Old one, begins in a laboratory.
Many test procedures are used to predict the performance in
use of the material undergoing test. Thus, agreement among
different laboratories concerning the prOposed test method
becomes a necessary although not always sufficient, crite-
rion of a good test procedure. The initiating laboratory has
the responsibility of varying the test conditions from the
nominial specified values to find out what happens. If the
laboratory finds it necessary to set and hold the relevant
conditions within very narrow limits in order to achieve
good repeatability, the usefulness of the test may be
seriously limited. It should be demonstrated that results
will not be altered by departures from specified values of
the test conditions that are likely to be encountered when
using routine equipment (say from one laboratory to another).
In other words, a good test procedure must not be too sensi-
tive-~it must tolerate departures from the specified condi-
tions as stressed by Youdenz. Interlaboratory testing
(repeatability) then becomes a confirmation of the claims
made by the procedure, obtaining results acceptable within
the limits Of some set standard deviation. From here the
procedure is then reviewed by the appropriate ASTM technical
committee for acceptance.

Many of the ASTM Standards are highly technical and
laborious for the average reader. For the purposes of lab

exercises it is not necessary to know all the information

4

contained in each standard cited. The purpose of reading the
ASTM Standards is to obtain basic knowledge concerning the
structures and Operation of the material testing equipment,
an understanding of calculations using the test data and a
feeling for the significance of the test. The easiest way

to understand each standard is to read the standard, run
several tests and then analyze the data. A point should not
be made to concentrate on sections concerned with test

equipment specifications or test equipment set up.

PROPOSAL 1: STATISTICS

Any laboratory or exercise worth its salt involving
data gathering utilizes statistical analysis to some
degree. This is because statistics functions as a
mathematical way of formalizing the amount of informa-
tion while decreasing the number of computations for
some experimental data. Statistics is also a way of
summarizing comprehensive data. Finally, statistics
allows conclusions about some pool of data (population),
with a stated error Of probability, to be made without
measuring all the elements of that population.

Thus, the examination of some of the basic
parameters of statistics is most apprOpriate for a
proposed first lab exercise, as well as a tool to be
used for ensuing exercises. ,To consider some of the
quantitative aspects of statistics within the framework
of a laboratory exercise, several guidelines must be
contemplated.

A. Only the basic parameters (not necessarily the
simplest) of statistics should be explored. Most
packaging students, especially beginning and
visiting students from industry, have either for-

gotten or had limited exposure to statistical

6
methods. What is more, most laboratories Obtain
maximum information using just these basic para-
meters.
The "idea" of statistics frightens most students
because of their vague notions of what it is and
what it can do. They many times cloak it with an
aura of mystery. The basic parameters of statistics
should be presented in such a way as to avoid the
students apprehension and puzzlement over the
subject.
The interests of both items A and B may best be
served by presenting statistics within the
framework of examining and measuring some quanti-
tative aspect of packaging. In this way, the
student could functionally learn statistics with-
out ever realizing it is indeed statistics he is
dealing with.
It is suggested that as an example of the quantita-
tive aspects of packaging, the specification and
measurement of bottle cap diameters be considered.
Of course this may be expanded to include any
number of other packaging dimensions or package
component dimensions, such as glass bottle or metal
can Specifications, film or board thicknesses

4, ASTM D645-675), or paper specifica-

(ASTM D58S-68
tions (ASTM D685-443). The choice of "what" to

measure will depend on what is readily available at

II.

III.

7
the time in terms of quantity and ease of working
with the dimension.

The following are the proposed parameters of statistics

to be considered with a laboratory framework. Each is

functionally defined, explained or used in the context
of the lab.

A. Definitions of pOpulation and sample.

B. Methods of finding central location-~mean or
average of sample (f), mean of pOpulation (u),
median (m) and mode.

C. Frequency distributions.

D. Measurement of diSpersion or variation-~standard
deviation.

E. Test of a statistical hypothesis, null hypothesis,
t-test, level of significance and knowledge of how
to use the table of critical values of t.

F. (Optional) The normal curve, x and z scales, con-
fidence intervals and knowledge of the table for
normal curve areas.

(For an elaborate examination of the above parameters,

the student should refer to Crow ct. a1.6, Freund and

Williams7, or Koosisg.)

Functionalization of Statistical Parameters

A. The stage is set by asking each lab group to view
itself as a representative of a company in the
production of glass bottles, seeking to contract for

a supply of bottle caps. Four sets of bottle caps

8

are distributed which represent sample sets from

four different bidding suppliers. They, the lab

group, are to determine whether or not these sample
sets satisfy required diameter specifications.

(The cap specifications may be given to each group

at the beginning of the lab, say 30 mm.)

1. Each cap of each set is measured in mm. The
sample sets may vary from 10 to 50. (This of
course depends on how much time and how many
caps are available.)

2. Each sample set of measurements could be
plotted to yield a frequency distribution.

(The student has now been exposed to concepts of

pOpulation, sample sets, data gathering and fre-

quency distribution.)

With data now gathered, it is a natural step to

next determine the central location of the data

followed by measuring dispersion or variation of
that same data. This may be accomplished by simply
presenting the mathematical notations for both

mean (f) and standard (5) deviations of sample sets

and ask the student to calculate these values. The

equations could be presented in this way:

A N
(x + x + . . . . x ) = x.
l 2 N i=1 1

ZIH

l. f =

This reads the summation of x1 (x1 being a

bottle cap within a set) i going from 1 to N,

9

where N denotes the sample size.

 

s = xi— x)
\i=l ”'1

Being interested in the size of the deviation

 

 

of our data from the mean, and not their signs,

the student can first square the deviations

and then average their squares.
The mean (f) and standard deviations (5) may be
calculated for all four sample sets. This gives
the student some novel information but it is of
little value unless put to use. To do this, each
lab group may be asked to perform a statistical
test for each sample set of bottle caps. This will
determine if the sample average (Y) of each sample
set is significantly different from the original
specification of the desired cap size.
1. Students are asked to compare (E) to their

original specification (A) i.e., Ho (null

hypothesis) becomes.u. A. (It should be
mentioned that the null hypothesis is called
such because we make the initial assumption
that there is no difference between.u and A.
Then we go about testing if there is a
difference.)

2. The t-test provides the student with informa-

tion concerning the validity of the comparison:

10

i-A

t = 5/fi

 

The student has already worked with f, s and

N and is given A (the specification). He may
then calculate a t-test value for all four
sample sets.

To use these calculated t-test values the stu-
dent must familiarize himself with the table of
t-test values. If the absolute value of the
t-test calculated value is not greater than the
t-test value found in the table, then H0 is not
significantly different from A, the original
specification. All four sample sets may be
tested in a like fashion to determine the
validity of H0 or f = A.

Since the normal curve is the cornerstone of
modern statistical theory, it may be apr0pos

to introduce the table of normal curve areas.
This is a bit Of powerful information to know,
since the probability of getting a value be-
tween two numbers is given by the corresponding
area under the curve. In order to use the
table of normal curves, the student must be
given didactic information concerning the
difference between the x scale and the 2 scale

employed by the table.

IV.

11

6. Five practice problems have been included which
give the student exercise in using basic
statistical parameters. They have been
arranged in order or presentation of the para—
meters within the lab and may be found in
Appendix B.

It may be argued that a lab in statistics is not
necessary since it is already presented in other pack-
aging courses. It could also be said that if statis-
tics is to be used in lab, why not introduce it in a
step fashion over a series of labs.

There are no laboratories that are absolutely
necessary, only ones which are beneficial. True,
statistics is represented in other packaging courses.
However, their presentations vary according to content,
approach and style. Moreover, it cannot be denied
that statistics is illusive with a high priority,
among students, to be forgotten. A laboratory on
statistics provides a functional approach geared for
laboratory use.

To present statistical parameters in a series
of labs allows for better familiarity and ease of
understanding if an initial introduction has been made
to begin with. It has been the experience of the author
that if this is not the case, the main themes of suc-
ceeding labs are Often superseded by confusion over

employing statistics. The following lab proposals

12
incorporate statistical techniques to some degree, but
only after the student has had the opportunity to more
fully explore these techniques in the fashion of an
introductory lab in statistics will he better under-

stand them.

PROPOSAL 2: STRESS-STRAIN ANALYSIS

Stress and strain characteristics (particularly the
tensile preperties of flexible packaging materials) are
of value for the relative comparison of one material to
another. From time to time, feedback received from
people in industry has indicated the wide range and
importance of material tensile values. It should be
stressed that tensile tests will indicate, not predict,
material performance. Evaluationslnrproducers of new
materials depend, in part, on the measurement Of tensile
properties. However, tensile values will vary with
changes in the test method. The standardization of
tensile test methods, then, becomes a crucial issue.

In Packaging 321, some of the basic elements of
stress strain theory were presented. This was to
serve as the theoretical network explaining load de-
formation curves produced by the Instron Testing
Machine. However, students hesitated to experiment
with the machine without a few procedural guidelines.
The Instron literally "looks" too complicated to use,
even when the student is armed with the theory to
explain load deformation curves. In view of what had

been discussed, the following are proposals for a

13

14

restructured lab on stress strain analysis.

A.

A brief presentation, in the context of the lab
exercise, is a necessary beginning. It should
concern itself with the following:

1. Hooke's Law, F = kL; this alone alludes to
tensile stress, strain, elongation and Young's
Modulus (elastic modulus).

2. Differences between shear stress and normal
stress.

3. Concepts of elasticity and plasticity. This
encompasses the prOportional limit, elastic
limit, yield point and modulus of elasticity.

4. Fracture characteristics--differences between
ductile and brittle materials, fatigue
fractures.

(For a more elaborate examination of the above

concepts, the student could familiarize himself

13, Modern Packaging Encyclopedia14,

.15)

with Jastrzebski

 

and Stevenson, 3:. E;
To actualize the contents of part A, each lab group
may run load deformation curves for five representa-

tive flexible packaging materials in accordance

with ASTM Standards D828-609, D638-7110

D882-6711. It is suggested that these materials be

and

considered for demonstrating different load
deformation curves: kraft paper, aluminum foil,

polyethylene, cellophane and polystyrene. Once

15

these materials have been tested and load deforma-
tion curves secured, the students may identify,
explain or calculate the following:

Breaking Factor

Tensile Strength

Tensile Strength at Break

% Elongation at Break
Yield Strength
% Elongation at Yield

Elastic Modulus
To alleviate confusion and the feeling of being
"swamped" with quantitative analysis, it would be
to the best interests of the student to present or
include a stress-strain curve with sample calcu-
lations as a model. Polyethylene nicely demon-
strates all necessary points of reference.
There has been much confusion on the part Of the
students, over the Operation of the Instron
Testing Machine. Complete instructions have never
been proposed for the procedural operation of the
Instron. This has been attempted and reflects on
the student as someone who is more than just a
button pusher and dial twister. Explanations of
the intrinsic functioning of the machine (Instron

12) serve to back operation-

Corp., Operating Manual
a1 instructions. In this way, the student will

hopefully become more appreciative of the

16

consequences or effects of manipulating controls.

It is also a frequent complaint by students that

"cookbook" operational instructions can become

offensive to the student, serving only to diminish

his sense of competence. A presentation of
operating instructions for the Instron (found in

Appendix C) stands as a suggested model, attempting

to take into consideration what has been discussed

above.

Another source of confusion stems from the lack of

comprehending effects of the differences between

crosshead motion and chart motion. This necessari-
ly leads to some adjustments in calculations de-
rived from the chart. The following examples are
suggested to clarify this important point.

1. In most standard load elongation tests, the
crosshead Speed does not equal the chart speed.
Since the curve is a representation of what
happens to a sample between the jaws of the
crosshead mechanism, and since all informative
data is taken from the curve, certain calibra-
tion factors must be considered to adjust
different speeds between crosshead and chart.
Elongation: For example, if the crosshead moves
at .5 inches per minute and the chart moves at
20 inches per minute, for every one inch the
jaws move apart, the pen moves along the x axis
of the chart 4 inches. To find elongation of
a sample, it is necessary to multiply the

distance the curve extends along the x axis by
the factor:

17

CROSSHEAD SPEED
CHART SPEED

 

Thus, if the distance along the chart is 3.75
inches, the elongation of the specimen is:

—% x 3.75 = 0.94 inches.

This means that although the pen traveled a
distance of 3.76 inches along the x axis, the
actual elongation of the sample in the jaws
was 0.94 inches.

2. For each test, the full scale load setting
determines the number of pounds required to
deflect the pen full scale. Less than full
scale deflections are a proportionate part of
the full scale load.

LOAD DETERMINATION: For example, if the full
scale load is 50 pounds, and the pen is

deflected to a chart reading of 6.8 at failure
of the sample, the load at failure is:

6.8
“ID x 50 = 34 pounds

II. In essence, this exercise accomplishes three things:

A.

It acquaints the student with elementary stress-
strain theory.

The theory is applied in testing various flexible
packaging materials and identifying various charac-
teristics of their consequent load deformation

CUI‘VGS .

18
C. The student becomes familiar with standard proce-
dures of testing tensile strength and the

operation of the Instron Testing Machine.

PROPOSAL 3: WATER VAPOR TRANSMISSION

The permeation prOperties of materials is of Obvious
value to packaging peOple, particularly those involved with
food packaging. Not only may the product within the package
change or be transformed from exposure to water vapor, but
the fundamental characteristics Of the packaging material
may change as well.

The lab taught in Packaging 422 concerning water
vapor transmission was, to be charitable, weak in methodology.
This has been perhaps the most confusing of all packaging
labs which led the student to constant erroneous and incon-
sistent results. The primary reason for this is that it
attempted to do too much with too little. Both individual
and component water vapor transmission tests were correlated
with total package water transmission rates and then to pre-
dictions Of shelf life. Knowing the water vapor transmission
of package components when comparing one material to another
is helpful in depicting which material is the better barrier
against water vapor. But other factors, such as sealing
effectiveness, fabrication, fluctuations in environmental
conditions, and handling make water vapor transmission values
for components of little value for predicting ultimate shelf

life.

19

20

Accelerated testing (exposure of package to super-
imposed extreme environmental conditions) of component
package materials is of some value in predicting shelf life
if they can be correlated with actual previously run field
tests. However, field tests yield results highly specific
for each particular package, are time consuming, expensive
and for practical purposes, beyond the scope of a packaging
lab at this time.

Moreover, the accelerated conditions utilized by the
cup test (ASTM E96-6616) have come more and more under the

18 and Woodzo, a test

scrutiny of industry. According to Peter
taking three or more days is inconveniently slow for quality
control purposes and absolutely useless for production con-
trol. As a consequence, more companies, especially major
cereal producers, are reverting to new advancements in the
measuring of water vapor transmission. Devices exist now,
employing a sensitive infrared hygrometer, which measure
water vapor permeance (and other vapors and gases as well) in
a matter of seconds and with a precision that the cup test
could only hope to approach.

Perhaps part of the reason the cup test has survived as
a standard method is due to the conservatism and inertia
within the paper and packaging world. However, the cup test
does have one significant advantage stemming from the fact
that permeance determinations are based upon fUndamental
parameters of temperature, humidity, time, weight and

specimen area as Wood19 asserts. On the assumption that all

21
these factors can be accurately measured and controlled, the
cup test stands as a method that, in principle, should not
require calibration against some reference standard. It
seems likely that the School of Packaging will in the future
acquire such an apparatus for quickly and accurately measur-
ing permeation of vapor and gases not only for instructional
use, but for more efficient research as well. Until then,
however, the cup test may still remain a functional method
for introducing the student to the material properties of
permeation, some of the problems involved in obtaining mean-
ingful measurements of permeation, and the concept of the
effect of environment (primarily temperature and relative
humidity) upon the permeation characteristics. In light of
the above discussion, the following revisions are suggested:
A. Have students obtain two (2) samples each Of the
following materials:
1. Glassine
2. Wax Coated Glassine

Paperboard (non-coated)

#04

Laminated Paper-Foil
5. 1 mil Polyethylene
6. 1 mil CellOphane

Here we have a wide range of commonly used
packaging sheet materials which surpasses the
limited selection of materials used in the permea-
bility lab of 422. There should be twelve samples

in all. Test these samples according to ASTM

22

Standard E96-6616

procedures C and D. (One set

of samples will be under conditions of low humidity
and high temperature, while the other set of samples
are subject to conditions of high humidity and

high temperature.)

Weighings should be made twice a day until the
requirements of the method are satisfied. Instruc-
tions should be included right in the lab for
proper use of the Fisher Gramatic Balance. (These
instructions already exist, being part of the old
Pkg.320 lab manual.)

As directed in section 15 of ASTM E96-6616

, plot

the results of successive weighings against

elapsed time. Also calculate water vapor trans~

mission, permeance and average permeability

(Also found in section 15). This should familia-

rize students with the differences in permeability

between various package materials and under differ-

ent environmental conditions.

To equate total package permeability with concepts

of accelerated testing, the student could follow

this course of procedure:

1. Either provide, or have students bring to lab,
four unit packages of the same size, construc-
tion and containing the same product (small

cereal packages are good sample units). Two

of these packages are to be used under room

23
conditions, two are to be used as experimental
samples.

2. At the beginning of the lab, place one container
in each of the two humidity cabinets with the
specified environmental conditions set by
procedures C and E of ASTM E96-6616. Also
at the beginning of the lab, open a third box
and remove enough contents to take a moisture
reading (% H20 by weight) on the Cenco
Moisture Balance under room conditions. Record
these results.

3. Toward the end of the lab procedure, the stu-
dent may remove both sample boxes from the
humidity cabinets. Take another moisture
reading on the Cenco Moisture Balance for each
of the two products which were in the humidity
cabinets. Also make another moisture reading
on the contents of the fourth box which has been
kept in the lab under room conditions.

4. Note and compare the difference between
moisture readings of all four samples. The two
samples in the humidity cabinets have been
exposed to accelerated conditions (an attempt
to Simulate accelerated environmental condi-
tions).

E. Isotherm moisture content curves may be included to

correlate moisture content with relative humidity

24

and temperature. These curves clearly demonstrate

that, depending on the temperature of the surround-

dings, moisture content of the package contents,

relative humidity of both the headspace within the

package and the air surrounding the package, water

vapor may be absorbed by the package contents to

establish equilibrium. In cases

of moist products

or extremely dry (low relative humidity) surround-

ing, the package contents may yield moisture to

its surrounding atmosphere to reach equilibrium.

The curves also demonstrate that

water vapor

transmission is not necessarily constant over time.

An isotherm moisture content curve may be construc-

ted by students using the following method.

1. At certain temperatures and when confined to

a closed space, certain chemicals when in

contact with a saturated aqueous solution will

demonstrate a Specific % humidity.

2. Air tight testing jars may be employed to indivi-

dually house saturated solutions of the following:

Phosphoric acid (H3PO4'l/2 H20)
Lithium chloride (LiCl-HZO)
Potassium acetate (KC2H302)
Calcium chloride (CaClz-OHZO)
Potassium carbonate (K2C03°2H20)
Ammonium Phosphate (NH4H2PO4)

% Humidity
(At approximately

20°C)
9
15
20
32

43,44
93

(For additional information, See General Chemical Tables

in Handbook of Chemistry and Physics1

 

7)

25
3. After several days are allowed for the solutions
to come to equilibrium with their confined
atmOSphere, dry cereal (perhaps corn flakes)
may be introduced into each chamber. After
exposure to the testing jar conditions for
several days, the product may be removed and
the moisture content determined using the
Cenco Moisture Balance. A curve of moisture
content vs. humidity may now be constructed.
The manufacturing of component test samples using
the test dishes and dessicant, involves the use of
molten wax in establishing a water proof seal. The
wax, if too hot, allows at best a clumsy applica-
tion, as the wax will run all over the sample in
most cases. It should be stressed that if the
temperature is kept low enough, a point will be
reached where the wax still melts but high viscosity
is retained. In such a state, the wax will not
run over the sample surface destroying it for
permeability measurements. Instead, a very neat
seal can be made. Related to this, it is a common
misfortune of lab instructors to be left at the end
of a term with a pile of wax coated dessicant
dishes. This condition may be promptly alleviated
if it is required that each lab group hand in 12

cleaned dessicant dishes along with their results.

26

Essentially, the student has been familiarized with
the water vapor transmission of several packaging materials
under two different accelerated environmental conditions.
The Cenco Moisture Balance was employed to demonstrate the
effects of the same two accelerated environmental conditions
on the total package contents. Finally, the effects of
humidity on moisture content were introduced in the construc-
tion of an isotherm moisture content curve for one particular

product.

PROPOSAL 4: CORRUGATED PAPERBOARD TESTING

Nearly every product used in our lifetime is packaged
in a box, the vast majority of these being corrugated
containers. Corrugated paperboard containers are mass
produced to match the mass produced goods they protect.

According to the Handbook of Corrugated and Solid
27

 

Fiberboard Boxes and Products , the production of

 

corrugated is even an indicator of the overall ”health"
of our economy.

One major problem in the corrugated paperboard
industry and experienced by many (Buchanan26, Oate527,
Wachuta28) who, in packaging, have found their way
into the corrugated paperboard industry, is one of
specification and lack of standardization. Not only
does board size, caliper, basis weight, quality, etc.,
vary from one manufacturer to another, but quantita-
tive test results such as the puncture test, edge
crush, flat crush, etc., also vary. (As a contrasting
example, the steel industry has rigid standards when
specifying Sheet metal. For instance, one may predict
with good certainty that the supply will arrive having

a certain weight, caliper, tensile strength, finish,

etc.) For corrugated paperboard there are no standard

27

28

machine settings nor any established ranges of simila-
rity between one manufacturer's board to another. The
corrugated box supplier can change the facing weight,
medium and adhesives as he sees fit.

Up to now, corrugated paperboard has been
represented in packaging labs as another packaging
material on which several ASTM tests could be applied.
These tests produced results which, to the student,
were somewhat less than meaningful. The student did
nothing with his results save produce them. The
following proposals are intended to correlate certain
test results on corrugated board to that unique situa-
tion which the student is likely to encounter in the
packaging world, that of Specifications.

A. Four test methods may be employed in evaluating a
sample shipment of corrugated board. These
tests include bursting strength, flat crush, edge
crush and whole box tOp to bottom compression
strength. A hypothetical problem will lie in
determining whether the results of these tests
performed on the given samples correlate with
given data for each test supplied by the instructor.
It may be assumed, as a hypothetical situation,
that for each test a given range Of values is
desirable and that this range favorably reflects
upon the specified use of the board. In other

words, the corrugated paperboard from one

29

manufacturer has proved competent in packaging

uses. The four standard tests mentioned above

were applied to the competent board to yield

certain sets Of results. These Specifications for

each test are given to the student. A new shipment
of corrugated paperboard is in question. Samples
from this new supply are tested to determine whether
or not they meet the specifications Of the pre-
viously used competent board.

1. One of the most important prOperties of the
corrugated paperboard is compressive strength.
The mechanical strength of corrugated paper-
board containers may be classified intO one
or the other categories of rough handling
(including vibration and shock) and stacking
strength. It also serves as a useful index
to the overall quality Of the fiberboard
materials and the workmanship in corrugated
and box shOp Operations.

2. Experiments have shown (Wachuta30) that the
box reaches its maximum load when the combined
board fails at or near a corner of the panel.
In as much as the corrugated paperboard in
this region of the box is essentially flat (by
comparison with the central region of the
panels) both liners and corrugated medium are

approximately uniformly stressed in edgewise

30

compression. For this reason, the edgewise
compression strength of the corrugated paper-
board (in the direction of the flutes) is of
primary importance to box strength.

3. The burst test (Mullen Test) has been
included primarily due to its wide spread use
and the paper industries' persistence in per-
petuating this test. The results of this test
depend on the materials used and not on the
structure Of the corrugated paperboard. For
this reason the burst strength is of little
use as an indicator of case performance if
one is interested in compressive strength.
However, the burst test is easy and quick to
carry out and it is an indication Of the abili-
ty Of cases tO contain contents such as cans,as
Buchanan26 suggests.

4. The flat crush is a different test altogether.
It is not directly correlated with compression
tests but evaluates the resistance of flutes in
corrugated paperboard to a crushing force
applied perpendicular to the surface of the
board. Low flat crush values may indicate
poor formation of corrugations, substandard
materials or damage to corrugations after they
are formed.

B. Test Specifications may be given to the student in

31

a number of ways. This will necessarily imply the

use of a few statistical techniques such as those

found in exercise #1.

1.

The student could simply be given the average
value and standard deviation for some pOpula-
tion of values for one particular test. All
ensuing tests on the sample board for that same
test would have to yield values 95% of which
must lie within say two standard deviations of
the given mean to be acceptable. For example,
a student could be given that for a specified
corrugated paperboard and container construc-
tion, the average compression strength is

589 pounds with a standard deviation of 42
pounds. 95% of the students test values would
then have to be within 84 pounds of the given
mean in order for the board to be accepted.
Taking a reverse approach to the one above,
students could perform the tests and derive
their own sample averages (i) and standard
deviations (5). Now, given some specification
value (A) and a level of significance 0%), the
student could reject or accept his sample
values on the basis of the t-test. For
example, a specification (A) for the Mullen
Test could be given as 200 psi. The student

may then test to within a level of significance

32
Of 0.05 whether or not there is a correspon-
dence between the given specification (A) and
the average sample test values.

3. The average value for some test may be given
with imposed plus and minus limits. In this
instance, 90% of the students' test values may
fall within the established limits of the
specification to be termed acceptable. For
example, a Specification for edge crush for
single wall B flute corrugated paperboard
might be 175 lbs./in. i 25 lbs.

For compression strength the Baldwin-Emery SR-4

Compression Testing Machine may be used in accor-

dance with ASTM D642-4722. A lab in Packaging

422 dealt with the making of corrugated paper-

board containers followed by simulating shipping

conditions using the inclined impact (or Conbur)
test. In simulating shipping conditions one is
talking about primarily shock and vibration. The

Conbur Test is grossly inferior to the shock and

vibration tests developed over the years. However,

corrugated container construction has merit in
introducing the student to handling corrugated

(Handbood of Corrugated and Solid Fiberboarngoxes

and Product527), figuring box dimensions and score
25

 

allowances (BRDA Technical Bulletin, No. 4 ). For

this reason, it is prOposed that corrugated

33

paperboard container construction be retained as an

exercise in itself and as a means of producing

samples for compression testing.

1. The dimensions of the sample boxes may be
uniformly set by supplying the student with,
for example, a glass bottle. The corrugated
paperboard container could then be constructed
to contain 12 of these bottles-~3 wide and 4
deep. The bottles are then used as both a
means Of determining the box dimensions and
as a means of testing the ”fit" Of the container
once it has been constructed.

2. TO be of any significance, it is advisable to
have ten or more compression values. It
would be expensive in both time and materials
used, for each student or group to manufacture
10 or more corrugated containers. It is
suggested that each student or group construct
one or two such containers to be used collec-
tively in one compression test schedule.

For the edgewise compressive strength of corrugated

paperboard the National Forge Compression Testing

Machine may be used in accordance with ASTM

2808-6923.

For flat crush of corrugated paperboard, the

National Forge Compression Testing Machine may be

used in conjunction with ASTM D1225-6624. It is

II.

III.

34
also feasible that the Instron Testing Machine, if
set up for compression testing, could also be
employed as an alternative in performing flat
crush tests.
F. For measures of bursting strength, the Model D
(Jumbo) Mullen Tester may be used with ASTM

21. Although the ASTM Standard does not

D2529-68
specifically apply to the measurement Of corrugated
paperboard, the general measuring procudure may be
used.
A science has burgeoned over the past years from
attempts to empirically relate edge crush values with
compression test values and establish a compression

26

strength formula for corrugated containers (Buchanan ,

29 and Wachuta30

Wachuta ). Such a correlation and for-
mula would greatly enhance the predictability Of
corrugated container performance. This could constitute
an appropriate part to any lab exercise dealing with
corrugated. However, as of this time there are
conflicting reports and somewhat less than precise
evidence about the tOpic. Until some consensus is
established and recognized, such information would

be better suited in a lecture context.

In summary, the student has been introduced to corru-
gated paperboard and major standard tests Of corrugated

board-~mainly the flat crush, edge crush, bursting and

compression test. The tests are Operated within an

35
experimental specifications paradigm in which the
student's test values are compared or correlated to
given specification values. Several statistical tech-
niques can be employed to make this comparison. During
the course of the tests, the student also becomes
familiar with corrugated handling, scoring and tech-

niques of container construction.

PROPOSAL S: PAPER AND RECYCLING

Paper, in all forms from newsprint to the finest
writing paper, is largely wood which has been reduced
to cellulose fibers by chemical or mechanical means

and rearranged into a sheet form. Carr38

pointed out,
as the waste problem increases and availability of
virgin materials decrease, productive nations all

over the world are finding it increasingly economical
to recover and reuse wood fiber products. This has
been the main drive behind the use of recycled materials,
one among them being recycled paper. In addition,
current movements in the concern for ecology and
conservation have Sponsored some pressure to use
recycled (secondary) fiber products. Recycling has
captured the public imagination and recycling research
programs are quite naturally prime material for news
headlines. The packaging industry uses a substantial
portion Of paper and paper products. It also contri-
butes to the solid waste problem. In reSponse to
packaging's involvement with solid waste, pollution and
the environment, an entire course, Packaging 340, was

develOped to study just this issue. Also, the charac-

teristics and processes of paper and paper manufacturing

36

II.

37
comprises a portion of packaging 320. Since paper
products will continue to be a major packaging material,
the purpose of this proposal is to focus on some of the
prOperties of general importance concerning virgin as
well as recycled paper.
The Council on Economic Priorities recognizes the
Groundwood Process as Oldest and simplest pulping
method. In this strictly mechanical process, raw
materials are pressed against large rotating corrugated
stones, discs or blades under a flow of water. The
abrasion pulverizes the raw material by physical force
until it is reduced to fiber bunches. These are
flushed away, pressed, matted and dried into a sheet.
Groundwood is the cleanest, cheapest and least
harmful pulping process. From the standpoint Of pollu-
tion control, groundwood is the Optimal process (The
Council on Economic Prioritiessg). (However, because
mechanical grinding tends to bruise and rupture the
fibers, the paper produced by this method is of lower
quality--less tear resistance and tensile strength,
for instance—-when compared to paper produced using
other chemical processes.) To introduce students to
the effects Of beating and different constituents Of
recycled paper, it is suggested that students utilize
the Valley Iron Works Groundwood pulp beater.
A. Various beating times may be crossed with several

"raw" materials.

38

 

 

 

 

 

 

 

 

 

 

Table 1: Various Raw Materials At Different Beating Times
(beating time in minutes)
15 30 45
100% newsprint
100% brown paper
(raw 50% newsprint
materials) 50% brown paper
100% virgin pulp
Brown paper in the previous table refers to Old
kraft grocery bags, wrapping paper, Old corrugated,
etC.
B. After each beating, the water may be drained and

screened through a fine wire mesh leaving the fibers
behind. The draining is accomplished via a brass
drain plug and connecting hose located to one end
of the water trough. The screening may take place
directly over the drain tile in the lab floor. It
is important that the fibers be distributed

evenly across the screen and not allowed to collect
in any one place. Shaking the screen while the
water drains through it and pressing the final
contents with any ridged flat surface should
provide a relatively even spread of fibers. The
screen may then be set aside to dry and the
resulting sheets examined for qualitative differ-

ences due to different beating times and composition.

III.

39
C. The orange colored lever, positioned by two lock
bolts, adjusts the tolerance between the revolving
blades and pulverizing plate through which the
fibers flow. Increasing this tolerance tends to
reduce fiber rupturing and bruising resulting in a
larger proportion of longer fibers. The Opposite
is true of decreasing the tolerance.‘ It is suggest-
ed that this adjustment be kept in the middle
position. AS an option, however, the student may
wish to use blade tolerance as another variable
effecting the beating process.
As the social and economic pressure to use recycled
material increases, meaningful Specifications for these
recycled materials will become:hmnrtant. With paper
and paper products, specifications Of the percentage
of recycled fibers can be deceiving. Recycled paper
differs as a function Of not only the level Of recycling
but also the quality and type Of recycled fibers used.
At this time, no standards exist which attempt to
define or in some way correlate one recycled paper to
another. Because of the many variables involved, it is
extremely difficult to microscopically differentiate a
recycled fiber from a non-recycled fiber (Van Huysen42).
In fact this reflects more Of an art than a science for
in most cases the differentiations reduce to judgemental
calls based on experience.

It is suggested that we turn from identifying

40

fibers to physical testing in an analytical procedure

to provide a basis for comparisons of paper materials.

The form of the physical testing (Britt37) is familiar

and will also serve the purpose Of acquainting the

student with various testing methods. If two samples
of paper differing in constitution are tested for this
difference, the testing methods should take on an added
utility or value dimension. This value dimension was
lacking in previous labs dealing with paper testing in
that the student would run methodical tests and derive
results which were not particularly meaningful or
relevant with a pivot point of comparison. The
following prOposals are a result of the discussion
above.

A. It would be naive to suggest Obtaining paper sam-
ples made Of 100% virgin pulp vs 100% recycled
pulp. Rather, it would be more realistic to Obtain
a sample Of paper whose constitution has a signifi-
cantly higher prOportion Of recycled fibers to
virgin fibers. Because of the problems of specifi-
cations already discussed, one would have to rely
on the supplier for information pertaining to the
amount and type Of recycled pulp that was used in
manufacturing the paper. However, this does not
constitute a major problem when it is considered
that the relative differences between materials

are the basis for testing them.

IV.

41
B. It is suggested that the student acquaint himself

with information on paper discussed in the Modern

40 37

Packaging Encyc10pedia and by Britt . The

 

physical testing should be preceded by determina-
tions of basis weight (ASTM D646-67)31, caliper
(ASTM D645-67)36 and machine direction versus cross
direction (ASTM D528-63)34. These values primarily
coordinate samples and sample cutting.

C. The physical tests reflecting any differences
between the samples may entail tensile strength
(ASTM D828-60)35, tear test (ASTM D689-62)33,
bursting strength (ASTM D774-67)32 and bending
stiffness (Taber Model lSO-B, V-S Stiffness
Tester Instruction Manual)41.

D. The physical tests may be applied to both types of
paper--the one type containing a proportionally
larger number Of recycled fibers, the other types
containing a proportionally larger number Of
virgin fibers. The compiled results, including
sample means and standard deviations, may be
quantitatively compared to distinguish differences.

Through this exercise, the student has been given a

functional introduction to recycled paper and paper

testing. The effects of variable beating times and
different constituent materials were examined in the
production of paper sheets from recycled fibers. Also

various test methods and apparatuses commonly used to

42
determine prOperties of paper were employed in
discerning differences between two sample papers of

unequal recycled constitution.

PROPOSAL 6: PLASTIC PACKAGES

From a review of current packaging literature one can
easily see the rapid increase in utilization Of various
plastics and their prOperties in the construction of
shrink, skin and blister packages, (particularly in the

51).

A. In the context of today's limited availability of

packaging of foods as cited by Young

corrugated paperboard and the relative availability
and stable prices of plastic films, (recognized by

Package Engineering48--particular1y polyethylene),

 

utilization of shrink packages has taken the most
astonishing leap. The shrink wrapping Of corrugated
trays and entire pallet loads leads one to these
advantages; reduced damage from over-the-road

hauls, reduced moisture penetration, contour fit,
(better stacking, especially with mixed cases), less
pilferage, more supermarket selling Space, cleaner
cases and an excellent customer acceptance of shrink

46

wrapped loads (Modern Packaging Encyclopedia and

 

Package Engineeringso). The Shrink film has become

 

a standard method of packaging.
B. A close kin to shrink packaging, skin packs are also

on the increase and they share many of the same

43

II.

44
advantages. Their unique importance is in immobi-

lizing the product with skin tight fits (Lindell
45 47)

This becomes a critical consideration in the packag-

and Cook , Modern Packaging Encyclopedia

 

ing of small component parts or a mixed lot Of

products (Package Engineering49).

 

The contour fit Of blister packs allOws them to be
primarily highly visible unit packs. Perhaps the
largest increase Of blister packaging in recent
years has been sponsored by the pharmaceutical
industry. According to Dean43 this type of packag-
ing is particularly preferred for convenience in
dispensing and product security, i.e., the product

is identified up to the point Of use.

The School Of Packaging has the machinery and many of

the materials to construct all three types of plastic

packages (skin, Shrink and blister packs). Because Of

the increase in use Of these forms Of packaging and

the continuing corrugated shortage, it is suggested that

students become familiar with both the materials and

machinery employed in forming these packages.

A.

The Cryovac Shrink Tunnel may be used for the prO-
duction Of shrink packages. The heat shrink
characteristic is usually built into the film
during manufacturing by stretching under controlled
conditions to create molecular orientation, or by

locking the film in stretched condition by cooling

45

(Griffin and Sacharrow44). This stored shrink
energy is released by heating to soften the plastic
or melt the plastic structure, allowing the film
to pull back toward its original position. Within
the plastics industry, Shrink films are Often
attributed with a "memory”. In other words, when
softened by heating, they try to assume their
previous shape. In producing shrink wraps the
student may be introduced to three different
variables affecting the wraps; type Of film,
temperature and conveyor speed.

1. It is suggested that students work with the
shrink prOperties of Polyvinyl Chloride,
Polyethylene (crosslinked) and Polypropylene.
Vinyl films are one of the more widely used
shrink films. It has high shrinkability, high
transparency, but only a medium barrier to

44).

Polyethylene films are used extensively for

gases and vapors (Griffin and Sacharrow

shrink wrapping pallet loads and are the most

readily available film (Modern Packaging

 

EncyclOpedia46). Polypropylene possesses good

 

barrier prOperties and high tensile strength
44)

Z. The student may vary the effects of temperature

(Griffin and Sacharrow

and conveyor speed control on the shrink tunnel.

Each student can vary the controls until he

46

determines the most suitable shrink package
for each film. To assist in this Operation the
student may refer to the film charts and graph

located in the Modern Packaging Encyglopedia46

 

under the section dealing with flexible packages.
3. To further explore the shrink characteristics
of each film the student may measure for
himself the percent of shrinkage. This may be
accomplished by cutting one specimen (10 in. x
10 in.) of each of the heat shrinkable films
and identify type, machine direction and cross
direction of each with a grease pencil. Place
each specimen between two pieces of chipboard
(12 in, x 12 in.) and place the specimen and
chipboard into a preheated Oven 250° F for 10
minutes. Dividing the changed area by the ori-
ginal area and subtracting this result from
100% gives the percent change in total area of
the shrink film. The procedure may be repeated
at various temperatures (300°F and 470°F) for
10 minute exposures.
The skin package is normally made by using the
product as a mold. A piece Of plastic film is
heated and drawn over the product by heat and
vacuum. Acquired recently, the Trans-Seal (model
SST-77) Skin Packaging Machine utilizes 5 1/2 mil

polyethylene to produce skin packages. The

47

operation Of the machine is quite simple and safe.

 

 

     

 

cycle 5tart cutoff
0
power on red pilot light emerg. step A
O) O
raise pre heat vacuum dwell lower
O .- 1:
Ag; 4

 

anue 1: Control Panel (SST-77)

1. Push the green "power on" button and select
preheat and vacuum dwell knob settings. Depress
the green ”cycle start" button. The bridge will
rise carrying with it a section Of shrink film.
The product and apprOpriate backing material
are now placed in position under the bridge.
Once the polyethylene in the raised bridge ends
its selected preheat cycle, the bridge will
lower and form the skin package under vacuum
automatically. Upon completion of the selected

vacuum cycle, the bridge will rise once more to

C.

48
allow the packaged product to be removed.
When the skin pack is out from beneath the
hood, press the yellow "cutoff” button. This
serves to both free the package from the roll
Of polyethylene and reloads the carriage with
new polyethylene sheeting for the next skin
pack. The bridge holding the polyethylene may
be manually raised and lowered by Operating the
blue "raise” or "lower" bottons.

2. The preheat time and vacuum dwell time are
variables affecting the quality of skin packs.
The student may apply different combinations of
vacuum and preheat time settings in determining
the most suitable skin pack for his particular
product.

A blister package utilizes a preformed "blister” or

"dome" made from a transparent sheet of plastic

which is then usually sealed or otherwise placed

on a paperboard or plastic card with the product

inside. The Atlas Vac-Machine may be used to make

blister molds. The variables here are type and
thickness Of film, vacuum time and heating time.

1. It is suggested that the student experiment
with two films-~polyvinyl chloride and cellulose
acetate of two thicknesses ranging from 4 mils
to 10 mils.

2. The student may again vary heating time and

III.

49

vacuum time in determining the effects of this
manipulation on the different films and thick-
nesses.

3. Vacuum formed blisters are usually thinner at
the top but thicker near the base web. The
distribution of thickness is in part determined
by the depth and angle of the draw. Distribu-
tions Of wall thickness can be checked by either
measurements or the use of a graph like lattice
marked on the surface of the film before heat-
ing. The degree of thinning is then indicated
by the dimensions and distortions of the squares
after the blister has been made. Strain
within the plastic blister can be observed under
polarized light.

Virtually anything that will fit through the shrink
tunnel may be wrapped as long as it is not combustible
or otherwise subject to degradation at the set tempera-
ture. The same thing holds for the skin pack machine
also. The blister pack requires a mold. In some

cases the product itself may serve as a mold, but in
most cases a prefabricated mold which accommodates the
product is used instead. For the Shrink and skin pack
it is suggested that the student bring to lab his own
product and package it. For the purposes of the blister
pack, several molds should be provided which demonstrate

different draws, heights and angles.

50
IV. The student, in this exercise, has been given selected
exposure to both the materials and methods used in the

growing fields of shrink, skin and blister packaging.

PROPOSAL 7: AEROSOLS

There existed as part of PKG 422, a lab concerning the

aerosol package system. There is no doubt the aerosols

are a unique facet of packaging with a stable course

of future development (Package Engineeringsz). However,

 

having taught this lab several times, the need for

several major revisions became prevalent to the author.

A.

The first revision prOposed is one of approach
because the PKG 422 aerosol lab, as taught previous-
ly, emphasized fill methods while diminishing the
construction and Operation Of the aerosol package.
The lab was set up to assimilate essentially four
different fill methods; the pressure fill, the
piston fill, the cold fill and the compressed gas
fill. The cold fill is seldom used by industry
anymore. The compressed gas fill is limited to
those aerosols intended for use in extremes of high
and low temperatures where liquid propellants
decrease in efficiency or become too dangerous to

use (Sanders54

). Moreover, the sophistication and
quantity Of different filling methods is changing
by the day. For these reasons, it is proposed that

the emphasis be shifted from filling methods to the

51

52

aerosol package system. This may be accomplished

by using three fill methods (pressure, cold and

compressed gas fill) as an instructional tool in
demonstrating the properties Of gases and prOpel-
lants in the aerosol system, rather than an end in
itself. The subject of fill methods may be more
apprOpriate within the context of lecture material
or field trip seminars.

Because of this switch in emphasis, it is possible

to cut down on material use by more than half and

still maintain as much, if not more, information.

The following is suggested:

1. In hfln the characteristics of five aerosol
packages could be compared, which would be
manufactured using two different fill methods.
These two methods employ combinations Of three
different prOpellants (Freon ll, Freon 12, and
compressed gas) with one common product (ethyl
alcohol).

Fill Method: COLD FILL
Formulations: -20% propellant (50% Freon 12,
50% Freon ll)
80% ethyl alcohol
Fill Method: PRESSURE FILL
Formulations: -SO% Propellant (30% Freon 12,
70% Freon ll)
50% ethyl alcohol
-50% propellant (70% Freon 12,
30% Freon ll)
50% ethyl alcohol .
-compressed gas 50psig-50% ethyl

alcohol

All percentages are by weight except for

53
compressed gas. Here 50% of product (ethyl
alcohol) refers to volume.

2. Notice that the ratio of Freon 11 to Freon 12
is held constant in the cold fill Operation,
while the ratio Of propellant to product is
varied. In the pressure fill method the ratio
of propellant to product is held constant while
the ratio Of Freon 11 to Freon 12 is changed.
The proposal is more concerned with the effects
of these ratio changes (propellant to product
and Freon 11 to Freon 12) than to the differ-
ences in fill method.

In order to understand the Operation of aerosol

packages, it is desirable to incorporate a few basic

gas laws and functionally work with them in lab.

Without this background theory, it is impossible to

understand the intrinsic working of an aerosol

package. The basic gas laws necessary should
include: (The student should refer to SandersS4
for an expanded presentation.)

1. Boyle's Law: The volume Of gas is inversely
proportional to the pressure if the temperature
is constant.

.1. .
V = k P k = constant (T constant)

2. Charles Law: The volume Of a gas is directly
prOportional to temperature if the pressure
remains constant.

V = kT (P constant)

54

3. Ideal Gas Law: An expression that relates the
pressure, volume and temperature.

PV = nRT where P

pressure exerted on the

gas

V = volume occupied by the
gas

n = number of moles Of gas
(concentration)

T = absolute temperature

R = gas constant

4. Raoult's Law concerns the lowering of vapor
pressure Of a liquid by the addition of another
substance. More specifically, the depression
of the vapor pressure of a solvent upon the
addition of a solute is proportional to the mole
fraction Of solute molecules in the solution.
(It is also proportional to the solvent;
solvent refers to the original liquid, solute
to the material being added.) Mathematically,
we may express this relation as:

N
PS = P1x1+P2x2+P3x3+... , P5 = Egg Pixi
where P5 = vapor pressure of solution
P = vapor pressure of pure components
x = mole fraction of component

The main identifying characteristic and "power"

behind any aerosol is its vapor pressure (Modern

53

Packaging_Encyclopedia ). The vapor pressure Of

 

an aerosol product is also an important property
to know for insurance of safe transportation and

54). For this reason it is suggested

use (Sanders
that each lab group calculate the vapor pressure
Of each formulation before actually manufacturing
the aerosol. By so doing, the student demonstrates

his ability to work with the basic gas laws. He

will also become aware of the differences between

55
compressed gas propellants and liquid propellants.
In addition, the effects of varying the ratio of
one liquid propellant to another becomes readily
understandable.

After calculating what the theoretical vapor
pressure should be for each aerosol, the student may
then manufacture the aerosol and compare its
actual vapor pressure to what was just calculated.

EXAMPLE: With these basic laws in mind,
the student has a means of calculating the vapor
pressure Of any solution if he knows the composi-
tion of the solution, the molecular weights of the
pure components and vapor pressures of the pure
components in the following five steps. (Students

54 for more detail)

may refer to Sanders
Step 1. The vapor pressures and molecular weights
of the two prOpellants are as follows:

Freon 12 VP (at 70°F) = 84.9 psia
Molecular weight = 120.9
Freon ll VP (at 70°F) = 13.4 psia
Molecular weight = 137.4

(psig-pound per square inch gauge; measures
are set at 0 for one atmosphere (14.7psi).
psia-pounds per square inch absolute; are
measures of pressure where 0 is a vacuum.
Thus, psia = psig + 14.7 psi, psig =

psia - 14.7 psi).

Step 2. Assume 100 g Of total solution. The moles
of the two component propellants are
obtained by dividing the component weights
each respectively by their molecular weight.

# moles Freon 12 ng—g = .744

Step 3.

Step 4.

Step 5.

56

10 _
# moles Freon 11 I377? - .078
Total moles in mixture = .822

The mole fraction of each component is
found by dividing the moles of each compo-
nent by the total moles in the solution.

.744

mole fraction Freon 12 = .905
.822

mole fraction Freon ll 121§ = .095
.822

The partial pressure of each component is
Obtained by multiplying the absolute
vapor pressure Of the pure component
(Freon 12 = 84.9 psia, Freon 11 = 13.4
psia) by its mole fraction in the liquid
phase.

partial pressure Freon 12
84.9 x .905 = 76.8 psia

partial pressure Freon 11
13.4 x .095 = 1.27 psia

The total pressure is merely the sum Of the
component partial pressures '

76.8+l.27 = 78.07 psia or 63.27 psig

One can see from this that by the addition-
of H)g of Freon 11 to 90 g of Freon 12,

we decrease the absolute pressure of

Freon 12 by 6.83 psi (at 70°F).

Knowing density allows the student to determine the

weight and volume of propellants and products that

can be packaged in an aerosol container. Because

Freon prOpellants boil at room temperature (21°C)

and one atmosphere, propellants should be metered

57
out directly into the aerosol can by either ml or
cc for purposes of the cold fill. By using weight
as a method of prOportioning the prOpellant (as the
aerosol packaging lab 422 suggested) the student
disseminates too much of the prOpellant to the
atmOSphere in the weighing process. Thus, each
lab group should use density in determining res-
pective volumes of each component to be used in a
formulation.

For example, to find the density of a Freon
12-114-ll(50/30/20) mixture at 70°F, and the rela-
tive amount of each (by weight and/or volume) used
in any fill method may be calculated as prescribed
by SanderSS4.
Step 1. The densities of the components are:

Freon 12 - 1.32 g/cc
Freon 114 - 1.47 g/cc
Freon ll - 1.48 g/cc
Step 2. Assume a total blend of 100 g. The volume
in cubic centimeters (cc) contributed by
each of the components is calculated by
dividing the weight of the component by

its density. For a 50/30/20 mixture by
weight the following volumes may be

 

determined.

Volume of 50.0 g of Freon 12 =I§§7 = 37.9cc
Volume of 30.0 g of Freon114 =§27 = 20.4cc
Volume of 20.0 g of Freon ll =1?28 = 13.5cc

Thus, to formulate this mixture, one must
add 50 g (or 37.9 cc) Of Freon 12 to 30 g
(or 20.4 cc) Of Freon 114 and 20.0 g

(or 13.5 cc) Freon ll.

 

II.

58
Step 3. The total volume of this 100 g blend is
simply the addition Of the volumes of each
individual component:
37.0 cc + 20.4 cc + 13.5 cc = 71.8 cc
Step 4. Since density is mass/volume, the total
density of the blend is the weight Of

the blend divided by the total volume Of
the blend.

Density of Blend = IEO'OCC = 1.39 g/cc

The gas laws are presented in theory in Packaging 320
lecture, however, they are not used in practice or
application. This exercise has suggested that they .—
be presented once again for the explicit purpose of
explaining two Operative functions. The first has been
mentioned already (the intrinsic workings of an aerosol
package). The second. function is that of the lab
procedure itself. The student will now realize the
premises behind techniques, such as changing a gas to a
liquid by lowering the temperature which is the basic
machinery Of the cold fill. He will also note that the
same results may be Obtained by application of pressure
on a gas, leading to the technique of pressure filling.
Moreover, the different characteristics Of the propel-
lants and their effects on one another will come to bear
more meaning. .A greater awareness of the possibilities
and implications of the aerosol package to the manufac-

turing and consumer world would, hOpefully, result.

 

APPENDI CES

APPENDIX A

ATTITUDE SURVEY

The following questionnaire was designed to elicit
evaluative, judgmental feedback from students pertaining to
two lab courses: Pkg 422 lab and Pkg 321 lab (or the revised
320 lab before it became independent and Pkg 321). The
questions, administered in the spring Of 1974 to students

familiar with the courses in question, were as follows:

Concerning lab 422 only, please rate on a scale of 1-5
how much you enjoyed or liked participating in the 422
labs (8 in all). A response of 1 indicates this was

the LEAST enjoyable lab. A response of 5 indicates that
this was the MOST enjoyable for you. A response of 3
indicates an AVERAGE lab--one which you neither enjoyed
or disliked. A response of 4 indicates a SLIGHTLY
ENJOYABLE lab and a response of 2 indicates a SLIGHTLY
DISAGREEABLE lab. '

1. Lab #1: Container Construction and Measurement
(Paperboard cartons-~set up box, folding carton)

2. Lab #2: Container Construction and Measurement
(Bags, wraps, overwraps)

3. Lab #3: Blister, Skin and Shrink Packages
(use of plastic films)

4. Lab #4: Aerosol Package System

5. Lab #5: Measuring the Efficiency of Packaging
Systems (glass bottles and caps)

6. Lab #6: Cereal Packages and Water Vapor Permeabi-
lity Tests

59

60

7. Lab #7: Corrugated Shipping Container (glass
bottles with or without partitions in RSC's)

8. Lab #8: Examination of Gases in Packages, Gas
Chromatography

Using the same rating scale Of 1-5, please consider
each lab in 422 again, from the point of view of most
information gained or conveyed by the experiment. A
response Of 1 means that you derived the LEAST informa-
tion from this lab. A reSponse of 5 indicates that you
learned a lot from the lab, or it conveyed to you the
MOST USEFUL information. A response of 3 indicates an
AVERAGE informational content, a response of 4 indicates
informational content value SLIGHTLY ABOVE AVERAGE and
a response Of 2 shows informational content value
SLIGHTLY BELOW AVERAGE.

9. Lab #1
10. Lab #2
11. Lab #3
12. Lab #4
13. Lab #5
14. Lab #6
15. Lab #7
16. Lab #8

For each of the following items, each lab in 422 is
associated with three things. kase choose the one
thing which you recall correctly, or most closely
associates with the lab.

17. Lab #1: l) Slit Lock Flaps 2) Gussets 3) End-Fold
Underfold

18. Lab #2: l) Slit Lock Flaps 2) Gussets 3) Bristol
Lund Formula

19. Lab #3: 1) Vacuum Time 2) Pressure Time
3) Plastic Flow

20. Lab #4: 1) Vacuum Time 2) Compressed Gas
3) Vacuum Fill

21. Lab #5: 1) Spring Torque Tester 2) Moisture
Balance 3) Heat Sealers

61

22. Lab #6: 1) Heat Sealers 2) Moisture Tunnel
3) Moisture Balance

23. Lab #7: 1) Incline Impact Tester 2) DrOp Test
3) Muller Test

24. Lab #8: 1) Carbon Dioxide, Nitrogen, Hydrogen
2) Carbon Dioxide, Nitrogen, Oxygen
3) Carbon Dioxide, Nitrogen, Water Vapor
25. Please indicate during which term you took Pkg 321
(or 320)
1) Fall Term 1973
2) Summer Term 1973
3) Spring Term 1973
4) Fall Term 1972
5) Summer Term 1972 or earlier

26. Please rate how much information you think you
derived from Pkg 321 lab on the same 1-5 scale.

27. Please rate how enjoyable or how much you liked
participating in Pkg 321 lab on the same 1-5
scale.

28. Overall, would you rate 321 above or below 422 lab?

1) Above 2) Slightly Above 3) About the same
4) Slightly Below 5) Below

FORMAT: As one can see, the questions were designed to
reflect both the affective value (enjoyableness) and informa-
tion content value of the labs. This was done to distinguish
one lab being rated informationally valuable, yet not enjoyable
to perform but perceived as having low informational value.
Thus, questions 1-8 dealt with the "enjoyableness" (Hedonic
rating) of the 422 labs and questions 9-16 with the informa-
tional value Of each lab in 422. Similarly, questions 26
and 27 pertained to the informational value and "enjoyable-
ness" Of lab 321 respectively.

Questions 17-24 were designed to establish recall and

possibly correlate high informational content with recall as

62

an indication Of a good lab procedure. Finally, question 28
pitted lab 321 against lab 422 for an evaluative comparison
of both "types? (Currently 422 is still taught using a
laboratory manual containing eight exercises. Packaging

321 is currently a two credit lab and largely independent
study with assigned readings and Optional research project.)

RESULTS: A total Of 32 current packaging students

filled out the questionnaire. The additive results of each

question were as follows:

Table 2: QUESTION NUMBER FOLLOWED.BY ACCUMMULATIVE RESPONSE ORDER

 

# 1) 1.1 # 2) 1. 2 # 3) 1.1 # 4) 1.2 # 5) 1.1 # 6) 1.1 # 7) 1.2
2.3 2.5 2.1 2.1 2.9 2.8 2.55
3.10 3.12 3. 2 3.5 3.10 3.10 3.7
4.15 4.10 4. 66 4.9 4.10 4.11 4.1
5.3 5.3 5.23 5.15 5.2 5.2 5.2
# 8) 1.4 # 9) 1.0 #10) 1. 0 #11) 1.0 #12) 1.2 #13) 1.1 #14) 1.2
2.3 2.5 2.6 2.3 2.1 2.5 2.4
3.9 3.11 3.15 3.8 3.3 3.11 3.11
4.10 4.12 4.9 4.10 4.11 4.14 4.9
5.6 5.4 5.2 5.11 5.16 5.1 5.6
#15) 1.1 #16) 1.2 #17)(;)23 #18)1.2 #19) 26#20) 1. 0 #21)(j)27
2.2 2.5 4 23 .0 (2)27 2.3
3.7 3.10 3. 5 .4 3.6 3.4 .3.1
4.2 4.8 4.1 4.0 4.0 4.1 4.0
5.2 5.7 5. 0 5 0 5.0 5.0 5.1
#22) 1.5 #23)(j)7 #24) 1.6 #25) 1.12#26) 1 6 #27) 1.7 #28) 1.3
2.4 2.4 (;)26 2.0 2.5 2.4 2.3
(:)22 3.3 .0 3.10 3.5 3.7 3.3
4.0 4.0 4.0 4.2 4 9 4.5 4.5
5.0 5.0 5.0 5.3 5 3 5.5 5.11

The correct response for question's 17-24 is circled.

DISCUSSION: The two most pOpular labs in Packaging 422

 

were by far those dealing with shrink, skin and blister pacs

(lab #3) and aerosols (lab #4). There was also a high

 

63
correlation between their "enjoyableness” and their rated
informational content value. The two least enjoyable labs
in Packaging 422 turned out to be those labs which dealt
with W.V.T. and shelf life (lab #6) and glass bottles and
caps (lab #5). The two labs rated the least informative were
those on bags, wraps and overwraps (lab #2) and gas chroma-
tography (lab #8). There was also good to fair recall on
Packaging 422 labs save for lab #6 and some confusion over
labs #1 and #7.

On the whole, lab 321 ranked about average in both
enjoyableness and informational value. The results also
indicated lab 321 rating below lab 422 in overall value
opinion. From this it may be inferred that laboratory
exercisesare preferred over independent study arrangements

supplemented with assigned readings.

 

APPENDIX B
SAMPLE STATISTICS PROBLEMS

1. Use the proper mathematical notation in finding the mean
(ll) of the following population distribution: 82, 64
87, 91, 59, 60, 77, 52, 99, 101, 63, 75, 88, 81, 47, 102,
39.

N

_ 1 QE: _ 1267 =
fl - N- Xi - --i-7-— 74.53
i=1

 

2. Using a random sample Of elements from above consisting

of 64, 77, 99, 88, compute x, the sample mean, and s,
the standard deviation of the sample.

 

 

 

N
— _ 1 _ 328=
X”'N' 2: X1“? 82
i=1
N* — 2
S = :E: (xi ' X3 = 224.67 = 14 99
N - 1 3 °
i=1

3. Establishing the null hypothesis of H = A, H = Y, i.e.,
A = x, use the t-test to confirm or r8ject th8 hypothesis.
(knowing x,Ax , s and N from above and given 0(= .05)

x -/¢ = 82 - 74.53
s/ V4 14.79/‘/ 4

T-table value = 3.182, the absolute value Of t calculated,
[997], is not greater than t-table value, thus, Ho holds.

 

t = = .997

64

65

4. Find the normal curve area between 2 = 0.50 and Z = .75.
using a table Of normal curve areas we find:

.2734
.1915

at Z = .75, area
at Z = .50, area

the area is found by taking the difference between
these two values:

(.2734 - .1915) = .0817 X 100 = 8.17%

5. The grades obtained by a large number of students in a
final examination in finger painting had a mean Of 68
and a standard deviation of 8.2. Assuming that these
grades are approximately distributed in a normal curve
fashion, below which grade will we find the lowest 10
percent of the class?

using the table of normal curve areas and the
equation:

 

.. ..x. .7“.
Z O"

we may solve for the value of x which designates that
grade below which we will find the lowest 10% of the
class. the lowest 10% of the area under the normal
curve is preceded by 40% of the area under the

normal curve to the left Of.u.. The closest
approximate 2 value at .40 is -l.28.

2=—-——;—/—‘- ; -l.28 =—3‘—‘—°—§— ; x (-1.28.X8.2)+68

U"
8'2 57.5

APPENDIX C

OPERATING INSTRUCTIONS FOR THE
INSTRON TESTING MACHINE

The Instron Testing Instrument incorporates a highly

sensitive electronic weighting system with load cells that

 

use strain gauges for detecting and recording tensile (or n~
compressive) loads. An applied load on the cell causes a i
proportional change in the resistance of the strain gauges.
The resulting signal is fed into the pen driving circuit of

a high-speed recorder.

There are basically two units composing the Instron
Machine. The crosshead mechanism, driven by two vertical
drive screws, houses the load cell at the very tOp. This
load cell connects to the upper jaw (clamp) of a pair which
function in holding test samples in place. The second
mechanism is the chart and recorder which is driven synchro-
nously with the crosshead. The following instructions,
if used carefully, will make the Operation of the machine
safe and simple. I
1) Turn on first the MAIN POWER.Swiufln then the AMPLIDYNE
switch, both located in the lower panel Of the recorder, (see
Figure 2). A warmup period Of about 10 to 15 minutes is
necessary before the load cell reaches maximum stability. A

red indicator light is illuminated when the main power switch
is in the ON position.

66

67

2) ZEROING. Turn on the PEN MOTOR SWITCH located on a
small panel above the right side Of the recorder case. (When
the pen power is Off, a red pilot light beside the switch
acts as a warning to return the power to the pen motor before
starting a test). Press the ZERO BUTTON and adjust the

ZERO CONTROL KNOB until the pen is at the desired zero (left)
position on the chart. (This effectively controls the zero
position Of the recorder independently of any signal from the
load cell.) When the ZERO BUTTON is now released, the pen
will probably go Off zero due to the imbalance in the load
cell circuit.

3) BALANCING. Remove the upper jaw from the load cell
coupling (Diagram #3), (pen should be OFF while removing
jaw). Turn COARSE BALANCE and then FINE BALANCE controls in
direction pen should move until the pen is brought back on
zero and it coincides with the previously adjusted zero
point. (This adjusts the balance of the resistance bridge
in the load cell). The adjustment of balance should always
be made with the LOAD SELECTOR SWITCH in the "1" position--
for the greatest accuracy of adjustment.

4) CALIBRATION PROCEDURE. With the position of the load
selector switch on "1”, attach the one pound weight to the
load cell coupling. Now turn pen ON and rotate the CALIBRA-
TION CONTROL KNOB until the pen comes to rest on the zero
line of the right side of the graph. Lock the calibration
knob in place by rotating the knurled ring behind the knob
in the clockwise direction. Turn PEN OFF, remove the one
pound weight and replace the upper jaw. (The sensitivity of
the load cell has now been adjusted so that the cell is
effectively calibrated for all the available ranges within
its rated capacity.)

5) With the jaw back in place, turn PEN ON and re-balance
(using the coarse and fine balance knobs) the pen needle back
to the zero position on the left side Of the graph. Lock the
fine balance knob in place and turn PEN OFF.

6) FULL SCALE LOAD SELECTOR essentially changes the
amplification of the load cell Signal for various values of
load range. The switch selects the full scale load range at
values Of 1, 2, 5, 10, 20, or 100. However, our particular
load cell has a maximum capacity of 50 pounds--do NOT use the
100 position of the full scale load selector. If the full
scale load of l is selected, a one pound tension on the upper
jaw will cause the needle to deflect across the entire span
of the graph. If a full scale load of 2 is chosen, it will
now take a tension of two pounds on the upper jaw to deflect
the needle to full range of the graph. A Similar reasoning
may be applied to tension of up to 50 pounds for this particu-
lar load cell. What full scale load setting to select

during a test depends upon the material being tested. In
most cases, a full scale load setting producing a graph over

 

68

the mid to maximum ranges of the chart paper for clear and
readily discernable results is Optimum. If the full scale
load is set too high, the resulting graph will not have
enough range for easy legibility. If the full scale load
is set too low, the pen will run right off the far right
edge Of the graph. WARNING: this causes an overload
situation on the load cell which may permanently deform

the strain gauge elements! If the needle runs over the range
of the chart, STOP THE TEST IMMEDIATELY and select a higher
full scale load setting in order to bring it back within
range.

7) CROSSHEAD SPEED CONTROL. The selection of crosshead
speed is governed by the characteristics Of the sample and
the desired test conditions. The crosshead is driven by a
set of gears located behind the CONTROL DRIVE DOOR SWITCH in
the lower right corner of the recorder (Figure 2). Opening
the door stops the crosshead should it be moving at the

time, i.e., the door must be closed to Operate the crosshead.

Behind the door switch you will find a center shaft
driven by either of two other shafts. The lower shaft is the
HIGH SPEED gear, rotating 10 times as fast as the upper one,
marked LOW.

The CROSSHEAD SPEED TABLES (attached to the back of the
door switch) give the selection and arrangement of change
gears to Obtain the various crosshead speeds, in combination
with the two positions of the MAIN DRIVE SHIFT LEVER.

The MAIN DRIVE SHIFT LEVER provides a change Of 10 to
1 in crosshead speed. This lever is Operated by the large
shift handle on the right side Of the instrument (Figure 3).
When pushed to the rear, the higher range of speed is obtain-
ed; when the lever is pulled forward, a 10 to 1 redUCtion
is accomplished. The neutral position is in the center of
the lever throw.

The MAIN DRIVE SHIFT LEVER functions together with the
CHANGE GEARS to produce the full 1000 to 1 range in available
crosshead speeds (see Figures 4 and 5).

To the right Of the change gear shafts, you will also
find a MANUAL POSITIONING KNOB which is used to fine adjust
the crosshead position when placing test samples between the
jaws. With this knob, the crossheads can be positioned
manually to within .001 inches quickly and accurately.

8) CHART DRIVE. A similar set of drive Shafts Operate the
chart speed (Figure 7). These are located on the rear of the
recorder mechanism which swing out. Use only that panel of
gear shafts designated "A SPEED". Again, change gears in
connection with three Shafts projecting from the gearbox,
determine the chart speeds. The central gear is driven by

69

the change gears on either of the two other shafts. The
upper driving shaft marked HIGH rotates 10 times as fast as
the LOW shaft.

A chart speed table showing the selection and arrange-
ments of the change gears to Obtain various chart speed, (in
inches/minute), is located on the inside back of the
recorder housing. There too, you will find a set of change
gears stored on studs. The chart speed is usually selected
to give a convenient length of record, which is usually
5 to 10 inches.

All change gears are installed by fitting the slot in
its hub over the key that is part of the collar on the shaft.
A knurled nut is then firmly screwed to the end of the
shaft to retain the gear in place.

70

Green Chart Pilot Light Red Pen Pilot Light

Chart Drive Switch Pen Motor Switch

Pen

Char p Push Button

Push Button

Full Scale Load
Selector Switch Manual Up/Down Switch
Zero Button Balance Control (Fine)
Knob

Zero Control

Knob
Calibration KnO

Balance Control
(Course) Knob

Control Drive Door
Switch (Closed)

Amplidyne On/Of
Switch

Main Power
On/Off Switch

 

Main Power
Pilot Light

Figure 2: Recorder Mechanism

////Tension Load Cell

L J

 

 

Upper Jaw

 

 

Safety Limit j:
Switches fl

 

Lower Jaw

 

 

 

Main Drive Shift
Lever

 

 

 

 

 

 

 

 

 

 

 

 

Figure 3: Crosshead Mechanism

72

IWodggl‘TT

 

 

 

 

 

 

 

 

Figures indi-

 

 

cate speeds if

 

inChes per min

 

 

 

B=Gear shift
Iever back
F=Gear Shift

Iéver
forward

 

 

 

 

 

Figure 4: Crosshead Gear Ratios

73

 

Mamal Positioning

 

Knob
Change Gear
Shafts .
\Cros shead
Drive Door
Switch
(Open)

 

 

 

 

 

 

 

Figure 5: Crosshead Door Switch

 

r—Change Gear Shafts

 

 

 

 

 

 

Figure 6: Recorder Gear Shafts

LIST OF REFERENCES

PERTAINING TO THE INTRODUCTION

1.

ASTM, 1973 Annual Book of ASTM Standards, Forward, Part
15.

Youden, W. J., "Experimental Design and ASTM Committees,"
Materials Research and Standards, November 1961, pp.
862-867.

PERTAINING TO PROPOSAL #1

3.

ASTM, Part 15, Conditioning Paper and Paper Products
For Testing, D685l44.

 

ASTM, Part 15, Sampling and Accepting a Single Lot of

Paper, Paperboard, Fiberboard, or RelatedIProducts,
D585-68.

ASTM, Part 15, Thickness of Paper and Paperboard,
D645-67.

Crow, E. L., Davis, F. A., and Maxfield, M. W., Statis-
tics Manual, Dover Publications,Inc., 1960.

 

Freund, John E., and Williams, Frank J., Modern Busi-
ness Statistics, Prentice Hall, 1969.

 

Koosis, Donald J., Business Statistics, John Wiley and
Sons, Inc., 1972.

 

PERTAINING TO PROPOSAL #2

9.

10.

11.

12.

ASTM, Part 15, Tensile Breaking Strength Of Paper and
Paperboard, D828f60.

 

ASTM, Part 27, Tensile Properties of Plastics, D638-71.

ASTM, Part 27, Tensile Properties of Thin Plastic
Sheeting, D882-67:

Instron Corporation, Operating Instructions for the
Instron Universal Testing Instrument, Manual 10-29-1
(A), 1964.

74

13.

14.

15.

75

Jastrzebski, 2., Nature and PrOperties Of Engineering
Materials, John Whiley and Sons, Inc., 1964.

 

 

Modern Packaging Encyclopedia, Section on Properties of
Packaging Films, McGraw-Hill, Inc.

 

Stevenson, Richard and Moore, R. B., Theory of Physics,
W. B. Saunders Co., 1967.

 

PERTAINING TO PROPOSAL #3

l6.

17.

18.

19.

20.

ASTM, Part 27, Water Vapor Transmission of Materials in
Sheet Form, E96T66.

 

 

Handbook of Chemistry and Physics. Chemical Rubber
Publishing Co., Fortieth Edition, (1958-59).

 

Petter, P. J., "Fast WVTR Readings by Infrared Beam,"
Modern Packaging, January, 1968.

 

Wood, R. C., "Evaluating Packaging Materials, "
Modern Converter, September, 1970.

 

Wood, R. C., "Rapid Evaluation of Moisture Barriers,"
Modern Converter, April 1972, pp. 32-36.

 

PERTAINING TO PROPOSAL #4

21.

22.

23.

24.

25.

26.

27.

28.

ASTM, Part 15, Bursting Strength Of Paperboard and Liner-
board, D2529-68.

 

ASTM, Part 15, Compression Test for Shipping Containers,
D642-47.

 

ASTM, Part 15, Edgewise Compressive Strength of
Corrugated Fiberboard, D2808-69.

 

 

ASTM, Part 15, Flat Crush of Corrugated Fiberboard,
D1225-66.

 

Boxboard Research and Development Association (BRDA)
Technical Bulletin No. 4, The Scoring and Folding of
Boxboard, June, 1962.

 

Buchanan, J. 8., "Testing Methods for the Components Of
Fiberboard Cases," Tappi, February, 1968.

Handbook of Corrugated and Solid Fiberboard Boxes and
Products, Fiberbox Association, 1968.

 

Oates, W. E., "Evolution of Corrugated Box Specification
P and G," Package Development, January/February, 1973.

 

29.

30.

76

Wachuta, J. R., McKee, R. C. and Gander, J. W.,
”Compression Strength Formula for Corrugated Boxes."
Paperboard Packaging, August, 1963.

 

Wachuta, J. R., McKee, R. C. and Gander, J. W., "Edge-
wise Compression Strength Of Corrugated Board? Paper-
board Packaging, November, 1961.

 

PERTAINING TO PROPOSAL #5

31.

32.

33.

34.
35.

36.

37.

38.

39.

40.

41.

42.

ASTM, Part 15, Basis Weight Of Paper and Paperboard,
D646—67.

 

ASTM, Part 15, BurstingfiStrength of Paper, D774-67.

 

ASTM, Part 15, Internal Tearing Resistance of Paper,
D689-62.

 

ASTM, Part 15, Machine Direction of Paper, D528-63.

 

ASTM, Part 15, Tensile Breaking Strength of Paper and
Paperboard, D828-60.

 

 

ASTM, Part 15, Thickness of Paper and Paperboard,
D645-67.

 

Britt, D. W., Handbook of Pulp and Paper Technology,
Sections on Paper Testing, pp. 665-674 and Beating,
pp. 333-337.

Carr, W. F., ”Many Problems Involved in Increasing
Utilization of Waste Paper," Paper Trade Journal,
May 17, 1971, pp. 48-52.

 

The Council on Economic Priorities, Paper Profits,
Pollution in the Pulp and Paper Industry, The MIT
Press, 1972.

 

 

Modern Packaging Encyclopedia, Section of Paper and
Paperboard, McGraw-Hill, Inc.

 

Taber Instrument Corporation, V-5 Stiffness Tester, Model

 

ISO-B, Instruction Manual, pp. 3-12.

 

Van Huysen, C. R., "The Development of a Procedure to
Analyze the Composition of Corrugated Linerboards,",
(An unpublished Master's thesis, Michigan State
University, 1972).

PERTAINING TO PROPOSAL #6

43.

Dean, D. A., "A Review of DevelOpments in the Blister
Packaging of Pharmaceuticals," International Conference
on Packaging Technology, 1972.

 

 

77

44. Griffin, R. C., and Sacharrow, 8., Basic Guide to
Plastics in Packaging, Cahners Books, 1973.

 

 

45. Lindell, J. and Cook, G. W., "Skin Packaging Cuts Costs

Down to Size,” Package Engineering, December 1973,
p. 46.

 

46. Modern Packaging Encyclopedia, Section on Flexible
Packages, McGraw—Hill, Inc.

 

47. Modern Packaging Encyclopedia, Section on Rigid and
Semi Rigid Plastic Packages (Blister and Skin Packages),
McGraw—Hill, Inc.

 

48. "Shrink Film and Trays Save $140,000," Package Engineer-
ing, October 1973, p. 60.

 

49. "Skin Packaging: Profitable Answer to Mixed Lot Woes,"
Package Engineering, September, 1973, p. 72.

 

50. "What? Shrink Wrap Loads at 32°?," Package Engineering,
August, 1973, p. 54.

 

51. Young, W. E., "Advances in Flexible Packaging,"
International Conference on Packaging Technology, 1972.

PERTAINING TO PROPOSAL #7

52. "Dreams? Or New Ideas in Packaging?," Package Engineer-
ing, December, 1973, p. 42.

 

53. Modern Packaging EncycIOpedia, Section on Aerosols,
Valves and PrOpellants, McGraw-Hill, Inc.

 

54. Sanders, Paul A., Principles of Aerosol Technolqu,
Section 1, Van NostrandiReinhOld Company, 1970.