Yam, Kit L. (ed.). The Wiley encyclopedia of packaging technology

Подождите немного. Документ загружается.

the efﬁcient, effective forward and reverse ﬂow and sto-

rage of goods, services and related information between

the point of origin and the point of consumption in order to

meet customers’ requirementsy. Logistics management

is an integrating function that coordinates and optimizes

all logistics activities, as well as integrates logistics activ-

ities with other functions’’ (1).

Logistical packaging is more than just cartons, crates,

and corrugated board (2). Also known as distribution

packaging and packaging logistics, it focuses on the

‘‘interaction and relationship between the logistical sys-

tem and the packaging system that add value to the

combined, overall, system—the Enterprise’’ (3).

Packaging affects the cost of every logistical activity

and has a signiﬁcant impact on the productivity of supply

chains. Transport and storage costs are directly related to

the size and density of packages. Handling cost depends

on unit-loading techniques. Inventory control depends on

the accuracy of manual or automatic identiﬁcation sys-

tems. Customer service depends on the protection afforded

to products as well as the cost to unpack and discard

packing materials. And the packaging postponement/spec-

ulation decision affects the cost of the entire logistical

system. An integrated logistics approach to packaging can

yield dramatic savings.

Logistical packaging facilitates product ﬂow during

manufacturing and distribution. Logistical packaging in-

cludes shipping containers for consumer goods (which are

almost always also in consumer packages), industrial

packaging for factors of production ranging from automo-

bile parts to food ingredients, and institutional packages.

There is also a packaging aspect to vehicle loading and

unloading, as well as to intermodal containerization.

Every factory and/or logistical operation receives and

ships logistical packaging; most operations unpack, re-

conﬁgure, and repack products, as well as purchase and

dispose of packaging materials.

This article deals with the role of packaging in the

logistics systems of supply chains. Readers who seek more

general information about logistics and supply chain

management are referred to texts in the ﬁeld (4–8).

LOGISTICAL PACKAGING FORMS

Since the early 1900s, common carriers in the United

States have tried to ‘‘regulate’’ the packages they trans-

port. The American Association of Railroads and the

American Trucking Association publish packaging mate-

rial ‘‘requirements’’ in their freight classiﬁcation books.

Most of the requirements were developed with the help of

the Fibre Box Association (or its predecessors) and use

more corrugated ﬁberboard material than may be re-

quired for adequate performance (2).

The justiﬁcation for these requirements has been that

carriers are responsible for paying in-transit damage

claims. One of the carriers’ common law liability defenses

is ‘‘an act of the shipper,’’ including insufﬁcient packaging,

and carriers have tried to maintain that only the packages

in the ‘‘Classiﬁcation’’ are ‘‘sufﬁcient.’’

These requirements have traditionally been a barrier

to packaging innovation. The existence of the ‘‘Cardboard

Rules’’ has caused many ﬁrms to make logistical packa-

ging simply a purchasing responsibility, rather than an

area for proactive management (9).

The barrier has fallen; however; since transportation

was deregulated in 1980, carriers have been able to

exercise much less control over logistical packaging. After

all, carriers are responsible only for in-transit damage,

and there are nonapproved packages that are at least as

protective as those in the Classiﬁcation.

The logistical channel members who buy, own, and sell

products have a much bigger stake in preventing damage

and controlling other packaging-related costs. The under-

lying logic of integrated logistics management is the

ability to control such systemwide costs.

Furthermore, transportation deregulation has caused

less freight to be subject to common carriers’ packaging

rules since much less freight pricing is governed by the

Classiﬁcation and more contracts are negotiated. More

freight today is shipped by full truckload, never handled

by the carriers’ workers, and is therefore less subject to

abuse in transit. Today, the Classiﬁcation ‘‘Cardboard

Rules’’ apply only to less-than-truckload (LTL) common-

carrier freight. And even LTL carriers will accept a

packaging exception to the rules if it is certiﬁed as passing

a series of performance tests (10).

This loosening of ‘‘rules’’ has triggered a renaissance in

logistical packaging. Shippers are questioning traditional

packaging materials and forms and are experimenting

with new, less costly packaging systems. For example,

some appliance shippers have reduced the cost of their

packaging by 50%, by replacing corrugated ﬁberboard

with ﬁlm-based (shrink- or stretch-wrap) packaging sys-

tems. Some furniture manufacturers have reduced their

package purchase and disposal costs to almost nothing by

utilizing ‘‘blanket wrap’’ (moving van) trucking service.

Assembly companies have switched from expendable to

reusable packaging. These innovations have also been

shown to dramatically reduce damage (11).

Most of the new packaging systems are simple varia-

tions of traditional packaging forms, using traditional

materials in new and innovative ways. They all have

two things in common: They are tailored to perform for

speciﬁc products and logistical systems, and they mini-

mize packaging purchase and solid-waste disposal costs.

The traditional logistical packaging materials and

forms

are

. Wood pallets

, crates, blocking, and bracing

. Corrugated ﬁberboard boxes, dividers, inserts, and

dunnage

. Solid ﬁberboard slipsheets and boxes

. Plastic and multiwall paper bags and drums

. Intermediate bulk containers, bulk bags

. Steel cans, pails, drums, and straps

. Steel racks and cages

. Fabric (burlap and woven plastic) bags and blankets

. Plastic ﬁlm shrink wrap and stretch wrap

. High-density plastic boxes, slipsheets, and pallets

. Blanket-wrapping, decks, and restraints

678 LOGISTICAL/DISTRIBUTION PACKAGING

. Plastic strapping

. Plastic foam cushioning and dunnage for fragile or

irregular shapes

Descriptions, properties, and speciﬁcations of most of

these materials can be found elsewhere in this

Encyclopedia.

LOGISTICAL PACKAGING PERFORMANCE

Logistical packaging only adds value because it functions

in a logistical system to provide protection, utility, and

communication. Performance speciﬁcation and value ana-

lysis, which can be used to guide packaging innovation,

employ a functional approach.

The amount of protection that a package must provide

depends on the characteristics of the product and condi-

tions in the logistical system. The relationship can be

conceptualized as

Product characteristics þ logistical hazards

¼ package protection required

Damage is a symptom of a system out of adjustment,

resulting from product problems, handling problems, or

packaging problems. Packaging is generally responsible

for the product quality that is maintained after the name

goes on.

The relevant product characteristics are those that can

be damaged during distribution. Examples include the

propensity of food to deteriorate as a result of tempera-

ture, oxygen, or moisture; the tendency for furniture to

rub during transit vehicle vibration; and the fragility of

products and packages that can break when dropped

during material handling operations.

The hazards of a logistical system depend on the types

of transportation, storage, and handling used. For exam-

ple, full truckload (TL) transportation generally causes

less damage than less-than-truckload (LTL) transporta-

tion where packages are handled repeatedly during trans-

loading operations and have many more chances to be

dropped or loaded beneath or beside damaging cargo.

Railroad shipment often incurs damage as a result of

railroad switching and coupling operations.

The hazards of international transportation range from

ﬂatbeds to bikecarts. Intermodal containerization for in-

ternational shipment has reduced impact and moisture

damage, compared to ‘‘breakbulk’’ shipping. But even

when products are shipped containerized, they will prob-

ably be handled in a breakbulk operation inland overseas

for which they require adequate packaging performance.

In general, moisture protection and protection from

oxidation are obtained by using barrier materials—which

keep water and water vapor, oxygen, and other destruc-

tive contaminants away from the product, and conserve

ﬂavor components in food—or by enclosing desiccant or

oxygen-absorbing packets. Shelf life can be lengthened by

the use of barrier materials and/or controlling the atmo-

sphere inside food packages. Temperature protection re-

quires insulated containers.

Protection against impacts can be obtained through the

use of cushions for shock-sensitive products. Protection to

prevent impacts from bursting a package wall requires

improving the walls’ tensile strength and puncture resis-

tance. To prevent products from shifting during railroad

switching and coupling impacts or as an intermodal con-

tainer is placed onto or removed from a ﬂatbed railcar,

trailer chassis, or ship, loads are blocked and braced to the

boxcar or container ﬂoor (12–14).

A basic rule for improving protection against impacts,

vibration, and compression is to always pack products

tightly so there is no headspace, no room to rattle, and a

shared reliance on box walls for stacking strength. Vibra-

tion or abrasion protection may also require changing

package surface or spring–mass characteristics. To im-

prove stacking, compression strength may need to be

added to the package walls.

The relative protectiveness of alternative packaging

systems can be evaluated and compared in laboratory

and ﬁeld tests. Standardized tests are available from the

ASTM International and the International Safe Transit

Association (ISTA), which can be used to develop more

specialized tests to evaluate speciﬁc properties. The best

tests target the package’s speciﬁc damage characteristics

(e.g., bags’ ends burst in side drops) and provide a measure

of the difference between alternative packages’ perfor-

mance (how much energy is required to burst), rather

than simple pass/fail tests.

The more liable the product is to damage and the more

hazardous the logistical system’s operations, or the higher

the cost of damage, the more packaging protection is

required. It is important to note, however, that the amount

of protection is not directly related to the cost of packaging.

In most cases it is possible to improve protection and

reduce packaging cost at the same time by simply choosing

more appropriate materials and methods. For example, the

U.S. Food for Peace program has been able to reduce the

number of paper piles in multiwall bags and improve

protection by simply changing the bag sealing method.

Accurate measurement of damage can provide the most

valuable information for directing attention to problems.

But

packaging decisions regarding

damage prevention are

often made without sufﬁcient information. Typical reports

of damage problems are unspeciﬁc as to the amount,

types, and causes. It is difﬁcult to quantify costs for

damage, because they are scattered among ﬁrms in a

logistical system (15). Since carriers are (to the extent of

their contract) responsible for the damage they cause,

documented in-transit damage claims are the ﬁrst place

to look for damage trends (16). Damage that is caused by

wholesalers and retailers is more elusive, and their co-

operation is required to report and evaluate losses.

In order to reduce waste, improve customer service,

and control packaging costs, some ﬁrms have developed

systems to track and manage product quality during

distribution (17). Such logistics quality-control systems

resemble systems for managing product quality during

manufacturing and include the following steps:

. Setting standards for critical defects

. Appraising conformance to standards, including

LOGISTICAL/DISTRIBUTION PACKAGING 679

. Monitoring and collecting data (e.g., electronic data

interchange)

. Reporting and evaluating data (Pareto analysis)

. Corrective action (modify the package, product, or

handling

Once a ﬁrm knows about its logistical damage, it can

target initiatives where they will do the most good. For

example, some furniture companies target speciﬁc

packages and products for improvement when damage

quantity and/or costs are higher than normal (18). Initia-

tives may include changing the product, changing the

logistical hazards, or changing the package. Speciﬁc in-

formation about damage is particularly useful when de-

veloping package tests and performance levels for

alternative packages. For example, some food manufac-

turers have learned that a most common source of damage

is box-cutter damage. In response, they have developed

easy-open display-ready packages (19).

In many cases, it costs much less to reduce the hazards

than to ‘‘improve’’ the packaging. Examples include

. The use of refrigerated transportation and storage to

protect fresh produce

. The use of storage racks in warehouses to prevent

compression damage

. Good sanitation practices during distribution to re-

duce the need for packaging to prevent vermin

infestation.

In other cases, the lowest-cost solution is to design

products to better survive shipment hazards. Product

design changes range from reducing fruit bruising

through genetic modiﬁcation, to improving the impact

resistance of an electronic product’s circuit-board fasten-

ers. An impact-resistant product requires little cushion-

ing, which minimizes cube and trash, and is more reliable

in use than a fragile product.

Packaging must also protect people in the logistical

system from injury and accidents. Workers’ ergonomics

and safety problems can be solved through better packa-

ging, especially since there are so many possibilities for

injury while working with packages. Routine package

handling can be linked to chronic stress injuries, and

material-handling accidents can kill people.

Routine manual handling of packages has always been

taken for granted, but it is traditionally the source of many

back injuries. OSHA guidelines answer the question ‘‘How

heavy should manually handled packages be?’’ with an

answer that depends on how far and how often the lifting is

done. For example, for ‘‘continuous high-frequency lifting,

variable tasks,’’ such as manual receiving operations,

weights below 17 lb are acceptable and represent nominal

risk, weights between 17 and 50 lb are acceptable only with

administrative or engineering controls, and packages

weighing over 50 lb are unacceptable (20).

Accidents happen. Personal-injury lawsuits involving

packaging materials and methods are increasing. The

liability judgment generally depends on whether the

accident could have been foreseen and whether adequate

packaging and training procedures were followed. For

example, when a long-shoreperson is injured by a bag

that slips from a stack, the fabric is accused of not

complying to standards, the unit-loading technique is

examined (maybe it should have been stretch-wrapped),

and the port practices are questioned. It is especially

important for ﬁrms to evaluate packages that are involved

in previous accidents, in order to prevent future

occurrences.

The packaging function of utility relates to how packa-

ging affects the productivity and efﬁciency of logistical

operations. All logistical operations are affected by packa-

ging utility—from truckloading and warehouse-picking

productivity, to transportation and storage cube utiliza-

tion, to customer productivity and packaging waste

reduction.

Productivity is the ratio of real output to real input:

Productivity ¼

number of packages output

logistics input

Logistical productivity is the ratio of the output of a

logistical activity (like loading a truck) to the input (like

labor and forklift time required). Most logistical produc-

tivity studies center around making the input, particu-

larly labor, work harder.

But packaging unitization and size reduction initia-

tives easily increase the output of logistical activities.

Almost all logistical activity outputs are described in

terms of number of packages. Some examples include

number of cartons loaded per hour into a trailer, number

of packages picked per hour at a distribution center, and

number of packages that ﬁt into a cubic foot (ft

; ‘‘cube

utilization’’) of vehicle or warehouse space (21). Testing

alternative packages for their logistical efﬁciency is a

simple matter of productivity measurement.

For example, palletization and/or unitization improves

the productivity of most handling operations. Warehouse-

order-picking productivity can be improved by making

packages easy to ﬁnd and recognize, by packing items in

order picking quantities (e.g., dozens), and by making it

easy to repack the heterogeneous order.

Cube utilization can be improved by reducing package

size. Package size can be reduced by concentrating pro-

ducts (e.g., orange juice and fabric softener) or by elim-

inating space inside packages by shipping items

unassembled, nested, and with minimal dunnage. In

most cases, the amount of dunnage materials (e.g., ex-

panded polystyrene loose-ﬁll) can be minimized simply by

reducing box size. Experts believe that improving cube

utilization is packaging’s greatest opportunity and predict

that, in general, packaging cube can be reduced by 50%,

doubling transportation efﬁciency.

Cube minimization is most important for lightweight

products (like assembled furniture) that ‘‘cube out’’ a

transport vehicle far below its weight limit. Trailer sizes

vary; most in the United States are 53 ft long, with inside

dimensions of 52.5 ft 99 in. 98 in. (high cube trailers

are 108 in. tall); and cargo weight limits are generally

about 40,000 to 44,000 lbs depending on the weight of the

680 LOGISTICAL/DISTRIBUTION PACKAGING

vehicle itself. On the other hand, heavy products (e.g.,

liquid in glass bottles) ‘‘weigh out’’ a transport vehicle

before it is ﬁlled. Weight can be reduced by changing the

product or the package. For example, substituting plastic

bottles for glass signiﬁcantly increases the number of

bottles transported in a trailer.

Packaging utility also depends on the compatibility of

packages with pallets and other material-handling equip-

ment used in a logistical system. Pallet-load efﬁciency can

be improved by designing shipping containers to better

ﬁt the footprint: Most grocery pallets in the United States

are 48’’ 40’’; most in Europe are 1200 mm 800 mm.

There are efforts underway to implement a compromise

standard of 1200 mm 1000 mm. In some logistical

systems, especially internationally, pallets are not used,

and packages may need the ability to be efﬁciently

manually handled (or by the longshoreperson’s hook)

repeatedly.

Packaging can also add utility for logistical customers.

The cost of unpacking is seldom considered by the ﬁrm

that packs products. But easy-opening features improve

retailer’s direct product proﬁtability by reducing custo-

mers’ costs of opening and displaying or installing

products.

Packaging disposal is also borne by logistical custo-

mers. Besides the environmental impact, logistical packa-

ging trash disposal costs money and can severely reduce a

customer’s productivity, particularly in nations such as

Canada and Germany, which have enacted legislation to

reduce packaging waste.

Packaging solutions to disposal problems include redu-

cing, reusing, and recycling. Reduction of packaging

also saves on packaging purchase costs. Packaging reuse

generally adds some costs for sorting and return trans-

portation. Recycling is growing in more widespread use

and gaining popularity, thus reducing costs and increas-

ing markets.

Recycling is a good disposal method for most logistical

packaging waste, since logistical packaging waste natu-

rally collects in large heterogeneous piles. Manufacturers,

warehouses, and retailers discard large amounts of pal-

lets, corrugated ﬁberboard, polyethylene ﬁlm, plastic

foam, and strapping. Recyclers appreciate such concen-

trated and relatively clean sources (compared to sorting

and cleaning curb-side and food-service wastes). Likewise,

purchasing packages made from recycled material en-

courages the growth of a recycled products market and

infrastructure. Recycling is sometimes called ‘‘reverse

logistics’’ (22).

One of the most popular trends is the use of more

reusable/returnable packaging for products such as as-

sembly parts, food ingredients, and snack chips, from

retail warehouse to store totes and intraplant shipments.

Most reusable packages are steel or plastic; some ﬁrms

reuse corrugated ﬁberboard boxes and pallet boxes. There

are also ﬂexible reusable systems: blanket-wrapping and

intermediate bulk containers such as bulk bags.

The growing reusable packaging applications all have

one thing in common: a short vertical marketing system. A

vertical marketing system (as contrasted to a ‘‘free-ﬂow’’

marketing system) is one in which the primary

participants are either corporate ownership, contracts, or

administration under the control of one ﬁrm (23).

A vertical marketing system is important because of

the need to control the movement of returnable containers

and the need to share the investment beneﬁts. All part-

ners in a returnable system must cooperate to maximize

container use, and an explicit relationship is required for

coordination and control. Otherwise, containers are easily

lost or misplaced. Alternatively, deposit systems may be

necessary in free-ﬂow marketing systems (like groceries),

where the channel members are linked only by transac-

tions. Deposit systems have been used for beverage bot-

tles, pallets, and steel drums.

The shipment cycle should be short, in terms of time

and space, in order to minimize the investment in the

container ‘‘ﬂeet’’ and to minimize return transportation

costs. The size of the investment depends on the number of

days in the cycle.

Deciding to invest in a returnable-packaging system

is a very different task from purchasing ‘‘expendable’’

containers. The decision involves considering explicit re-

levant costs—purchase cost, including number of

packages in the cycle, and transport cost—versus the

purchase and disposal cost of expendables. Intangible

beneﬁts such as improved factory housekeeping, improved

ergonomics, and decreased damage are often considered.

Generally, there are a number of unexpected costs, includ-

ing sorting, tracking, and cleaning. Most ﬁnancial

analysis of returnable systems has been limited to ‘‘pay-

back period’’ justiﬁcation rather than net present value

calculations, which would demonstrate the strategic and

proﬁt potential of a returnable-packaging system

investment.

The efﬁciency of the logistics system that returns

containers or pallets to use determines the cost as well

as the environmental sustainability (24). Most logistical

systems for reusable packaging use a shared pool system,

rather than a strict one-for-one return. These can be

owned by the supply chain, rented from third parties or

traded in a free market (such as the market for used

wooden

pallets) (25).

The

function of communication is becoming more im-

portant for logistical packaging, as logistical management

information systems become more comprehensive. For all

practical purposes, the package symbolizes the product

throughout logistical channels. Correct identiﬁcation of

stock-keeping units (including name, brand, size, color),

counting, special shipping instructions (e.g., ‘‘Hazar-

dous’’), and address are critical to quality logistical in-

formation management. International shipments require

the language of origin, destination, and intermediate

stops, as well as international markings for handling

instructions.

For example, automatic identiﬁcation (e.g., bar coding

or radio-frequency identiﬁcation) highlights the commu-

nication function and can interface with information

systems throughout a logistical system if the symbology

is standardized (see Radio Frequency Identiﬁcation

(RFID)). But even manually readable packaging

must be clearly legible to interface with logistical man-

agement information systems; workers must be able to

LOGISTICAL/DISTRIBUTION PACKAGING 681

quickly recognize a package from its label. Almost every

logistical activi ty—ent ails reading the package and re-

cording or changing its status in an information system—

inventory control, shipping a nd receiving, order picking,

sorting, and tracking. Automatic identiﬁcation technolo-

gies such as bar coding and radio-f requency identiﬁ cation

enable a systems approach t o managing logistical infor-

matio n where ever y input is standardized and errors are

reduced.

The functions of packaging—protection, utility, and

communication—are the basis for packaging performance

speciﬁcations. Performance speciﬁcations outline what the

package must do (e.g., be able to survive an impact). The

speciﬁcation of performance guides packaging changes

that add value and reduce costs.

Many ﬁrms and government agencies have adopted

packaging performance speciﬁcations for logistical packa-

ging. For example, the U.S. Department of Transportation

(DOT) has replaced hazardous-material packaging speci-

ﬁcations with ‘‘Performance Standards’’ that do not specify

material, but do specify tests (e.g., impact, permeability, or

compatibility tests) for speciﬁc product/package/hazard

conditions.

Performance speciﬁcations encourage innovation, and

innovation results in lower pac kaging costs. Mat erial

speciﬁcations are necessary, of c ourse, for routine packa-

ging purchases, but adding a performance speciﬁcation

offers two beneﬁts: (1) a ﬁrm that examines its current

and expected leve ls of packaging performance will always

uncov er opportunities to cut pac kaging-relat ed costs;

and (2) suppliers who are invited to compete on a perfor-

mance basis will always suggest lower-cost packaging

solutions.

TYPICAL LOGISTICAL PACKAGING PROBLEMS

There are three types of logistical packaging problem:

engineering problems, cost problems, and logistical pro-

blems with packaging solutions. Generally, logistical

packaging problems require on-site investigations—the

best way to ﬁnd out more is to go and look.

Packaging professionals use engineering principles of

material science to develop new packages and solve pro-

tection and productivity problems. The most common

material properties that can be scientiﬁcally determined

are cushioning (for fragile products), impact and vibration

resistance of ﬁlled packages (26), shelf life and perme-

ability for oxygen- or moisture-sensitive food products

(27), and compression strength for hard-to-stack products

(28). Packaging professionals also use some industrial

engineering principles to conﬁgure packing operations

and choose packaging machinery.

Management of logistical packaging, however, involves

more than ‘‘package engineering.’’ Most packaging pro-

blem solving is not associated with developing new

packages for new products. In fact, most ‘‘new’’ logistical

packages are simply variations of packages used for

similar products and require very little ‘‘engineering.’’

The second principal activity of a packaging profes-

sional is to reduce the cost of purchasing packaging

materials and the cost of packing operations. The most

common areas for cost reduction are reducing package

weight or size, material substitution, size reduction, auto-

mation of manual tasks, and standardization. Innovative

incremental packaging solutions, which reduce cost and

improve performance, abound in the packaging supply

industry. Manufacturers of packaging materials and

equipment are sources of a great amount of free, if

potentially biased, consulting advice, so it is wise to

consult more than one. Other good references include

trade journals such as Packaging, Materials Handling

Engineering, Modern Materials Handling, and Transpor-

tation and Distribution.

The third type of packaging problem consists of logis-

tical problems and opportunities with packaging solutions.

Packaging can reduce the cost of every logistical activity:

transport, storage, handling, and inventory control, and it

can improve customer service. It can reduce the cost of

damage, safety, and packaging disposal. Integrated man-

agement of packaging and logistics is required, if a ﬁrm is

to realize such opportunities (29–32).

When packaging and logistics are integrated, it is

reasonable to consider where and when packaging opera-

tions ﬁt into a logistical channel. Packaging postponement

can dramatically reduce the cost of an entire logistical

system.

The logistical concepts of postponement and speculation

can be proﬁtably applied to packaging logistics. These

question where and when to add value (time, place, and

form utility) in distribution channels in order to reduce

costs or improve customer service. The principle of spec-

ulation says that manufacturing and shipping should

occur at the earliest possible time in the marketing ﬂow

in order to achieve economies of scale. The opposite

principle of time and form postponement reduces risk by

requiring that changes in form and identity and inventory

location occur at the latest possible point in the marketing

ﬂow

, since every

differentiation that makes a product

more suitable for a speciﬁed segment of the market makes

it less suitable for other segments. The traditional inven-

tory tradeoff is to reduce risk by postponement (just-in-

time logistics) or to reduce cost with economies of scale

(forward buying) (33).

Traditionally, the packaging point for bulk products

has been postponed or speculated, on the basis of product

and market conditions. For example, produce is canned

in the fall and stored in ‘‘bright’’ cans; labeling is post-

poned until food-marketing companies buy and brand it

throughout the year. Labeling postponement minimizes

the risk of inventory misforecasts and economizes

on canning production during a busy season. On the

other hand, processing and packaging of frozen fruit

concentrates, such as orange or grapefruit juice, is

an example of speculation, resulting in low costs

because weight is eliminated before shipping and homo-

genous waste at the orchard is processed for animal

food.

Postponement and speculation also apply to assembly

and packaging of more sophisticated products in a global

market with global sources. When products are similar,

but differentiated for local markets, assembly and

682 LOGISTICAL/DISTRIBUTION PACKAGING

packaging postponement offers opportunities for custo-

mizing packaging for the local markets while minimizing

long-distance transport costs and the amount of differen-

tiated inventory in the pipeline.

For example, one of the largest cost-savings initiatives

in packaging history (tens of millions of dollars per year) is

a case of international packaging postponement. To reduce

high transport and inventory management costs, a major

electronics manufacturer has postponed the packaging for

products shipped overseas. The products are shipped in

‘‘bulk packs,’’ palletized and stretch-wrapped, with mini-

mal interleaving between layers. Once there, products are

packaged to order. Transport costs have been cut in half,

since differentiation and cushioning are postponed until

they are required (34).

INNOVATIVE LOGISTICAL PACKAGING

This article has approached the ﬁeld of logistical packa-

ging from a nontraditional perspective. The reason for this

approach is to encourage innovative packaging solutions

to logistical problems. Most traditional packaging forms

date from the early 1900s and are the most costly packa-

ging systems available. Innovation represents a dramatic

potential for savings.

Packaging innovation is a process of problem identiﬁ-

cation, ﬁnding and testing potential solutions, deciding

which action to take, and following through to implemen-

tation. It requires proactive management by a project

champion—usually a packaging professional. It also re-

quires a systems and team approach, since packaging

affects so many other functional areas such as marketing,

operations, plant and product engineering, logistics, ac-

counting, and ﬁnance.

Identiﬁcation of packaging-related problems is the ﬁrst

step. Problems of cost, protection, utility, and communica-

tion may be identiﬁed by customers, salespeople, logistical

managers, or packaging professionals. The search for

packaging solutions may be formal or informal, but the

innovation process requires a potential solution before it

can proceed. Sometimes problems languish for years

before someone thinks of a good solution. Ideas for poten-

tial solutions can come from suppliers or consultants or

from the advice of colleagues. Alternative packages are

judged, subjectively or in lab tests, for their protection,

utility, and communication performance, as well as sys-

temwide cost implications. Next, the ‘‘best’’ solution

packages are tested in the ﬁeld (test shipments) and for

market acceptance. The early rollout is a period of ﬁne-

tuning. Problems with the new package are discovered

and corrected. Sustained implementation returns to a new

level of business as usual—generally with substantial cost

savings.

CONCLUSION

This chapter has shown that, beyond its purchase cost,

packaging affects the cost of every logistical activity.

Package size affects transportation cost; unitization

methods affect order picking and handling costs; identiﬁ-

cation techniques affect inventory control; and customer

service depends on damage control and the cost to unpack

and discard packaging. Firms that manage packaging

from an integrated logistical perspective, rather than

from a traditional purchasing perspective, will ﬁnd

many opportunities for improving their proﬁtability.

BIBLIOGRAPHY

1. Council of Supply Chain Management Professionals. Supply

Chain Management and Logistics Management Deﬁnitions,

2007 (cited 2007 August 2); Available from: http://cscmp.org/

AboutCSCMP/Deﬁnitions/Deﬁnitions.asp.

2. D. Twede and S. E. M. Selke, Cartons, Crates and Corrugated

Board—Handbook of Paper and Wood Packaging Technology,

DEStech Publications, Lancaster, Pennsylvania: Inc., 2005.

3. M. Saghir, Packag. Technol. Sci. 15, 37–46 (2002).

4. D. J. Bowersox, D. Closs, and T. P. Stank, eds., 21st Century

Logistics: Maing Supply Chain Integration a Reality. Council

of Logistics Management, Oak Brook, IL, 1999.

5. D. J. Bowersox, D. J. Closs, and M. B. Cooper, eds., Supply

Chain Logistics Management. McGraw-Hill, Boston, MA,

2002.

6. J. T. Mentzer, Supply Chain Management, Sage Publications,

Thousand Oaks, CA, 2001.

7. D. Blanchard, Supply Chain Management: Best Practices.

Wiley, Hoboken, NJ, 2007.

8. H. Stadtler and C. Kilger, eds., Supply Chain Management

and Advanced Planning: Concepts, Models, Software and

Case Studies, 3rd edition Springer, Berlin, New York, 2005.

9. M. A. McGinnis and C. J. Hollon, J. Bus. Logist. 1, 45–62

(1978).

10. International Safe Transit Association, Pre-Shipment Test

Methods. ISTA Annual, Chicago.

11. D. Twede, J. Busi. Logist. 13, 69–94 (1992).

12. J. Agnew and J. Huntley, eds., Container Stowage: A Practical

Approach. Container Publications Ltd., Dover, NJ, 1972.

13. United States. Maritime Administration., A Shipper’s Guide

to Stowage of Cargo in Marine Containers. U.S. Department

of Transportation Documents, U.S. G.P.O., 1982.

14. Association of American Railroads, Loading Methods for

Closed Cars, AAR, Chicago, various dates.

15. J. L. Cavinato, Analysis of Loss and Damage in a Procure-

ment Distribution System Using a Shrinkage Approach, in

Business Logistics, Pennsylvania State University, State

College, PA, 1975.

16. W. J. Augello, in G. Pezold, ed., Transportation, Logistics and

the Law, 2nd edition, Transportation Consumer Protection

Council, Huntington, NY, 2004.

17. D. Twede, Packag. Technol. Sci. 4, 305–310 (1991).

18. T. J. Lowery, Quality Control of Products During Distribution,

in Logistical Packaging Innovation, Council of Logistics

Management, Chicago, 1991.

19. W. Thompson, Improving Customer Service ‘‘Packages’’:

Direct Product Proﬁtability,inLogistical Packaging Innova-

tion, Council of Logistics Management, Chicago, 1991.

20. T. R. Waters, Applications Manual for the Revised NIOSH

Lifting Equation, U.S. Department of Health and Human

Services, Public Health Service, National Technical Informa-

tion Service, Cincinnati, OH, 1994.

LOGISTICAL/DISTRIBUTION PACKAGING

683

21. A. T. Kearney, Measuring and Improving Productivity in

Physical Distribution, Council of Logistics Management,

Chicago, IL, 1984.

22. M. P. A. R. D. de Brito, ‘‘A Framework for Reverse Logistics,’’

in Reverse Logistics: Quantitative Models for Closed-Loop

Supply Chains, M.F. Rommert Dekker, Karl Inderfurth and

Luk N. Van Wassenhove, eds., Springer-Verlag, Berlin, 2003,

pp. 3–27.

23. D. Twede and R. Clarke, J. Market. Channels Distrib. Syst.

Strategy Manage. 12, 7–26 (2004).

24. L. Kroon and G. Vrijens, Int. J. Phys. Distrib. Logist. Manage.

25, 56–69 (1995).

25. D. Twede, D. Mollenkopf, and C. Guzman-Siller, A Market

Driven Investigation of Pallet Trends in Grocery Chains,

National Wooden Pallet and Container Association, Washing-

ton, DC, 2006

26. R. K. Brandenburg and J. J.-L. Lee, Fundamentals of

Packaging Dynamics, 4th edition, L.A.B., Skaneateles, NY,

1991.

27. G. L. Robertson, Food Packaging : Principles and Practice,2nd

edition, Taylor & Francis/CRC Press, Boca Raton, FL, 2006.

28. G. G. Maltenfort, Corrugated Shipping Containers: An En-

gineering Approach, revised edition, Jelmar Publishing Co.,

Plainview, NY., 1996, p. vi.

29. K. Johansson, A. Lorentzon Karlsson, C. Olsmats, and L.

Tiliander , Packaging Logistics, Packforsk, Kista, Sweden, 1997.

30. M. Johnsson, ‘‘Packaging Logistics—A Value Added Ap-

proach,’’ in Engineering Logistics, Lund University, Lund,

Sweden, 1998.

31. M. Jahre, ‘‘Packaging Logistics for Improving the Environ-

ment and Economics in the Value Chain,’’ in Logistical

Packaging Review, Econpap, A

rhus, Denmark, 2000.

32. C. W. Ebeling, Integrated Packaging Systems for Transporta-

tion and Distribution, Marcel Dekker, New York, 1990.

33. L. P. Bucklin,. J. Market. Res. 2, 26–32 (1965).

34. D. Twede, R. H. Clarke, and J. A. Tait, Packag. Technol. Sci.

13, 105–115 (2000).

684 LOGISTICAL/DISTRIBUTION PACKAGING

MACHINE DIRECTION ORIENTATION

D. RYAN BREESE

Eclipse Film Technologies,

Hamilton, Ohio

ERIC HATFIELD

Vice President, MDO

Engineering, Cincinnati, Ohio

INTRODUCTION

In the MDO process, a polymer ﬁlm, tube, or sheet is

uniaxially stretched in the machine direction. MDO is also

commonly seen as the ﬁrst of two steps associated with

biaxially orienting ﬁlms, with the second step being the

tentering, which stretches the ﬁlm in the transverse

direction.

Machine direction orientation (MDO) of polymer ﬁlms

provides improvements in stiffness, strength, optics, and

barrier and has been commercially practiced for decades.

MDO is being utilized to produce ﬁlms for a wide range of

applications and marketplaces, including food, medical,

and industrial packaging. Due to the strong economic

drivers, companies are utilizing MDO ﬁlms at an ever-

increasing rate (1, 2). The improvement in mechanical

properties allows for the downgauging of a current ﬁlm,

which is the most common use of MDO ﬁlms. In addition,

MDO ﬁlms can be used to replace a less desirable sub-

strate, such as one that is more costly, is more difﬁcult to

source, is less receptive to ink, has a lower yield (MSI/lb),

and/or is less environmentally friendly. Also, through the

use of various polymers and ﬁlm extrusion technologies,

MDO can be used to produce a single ﬁlm that has a

desired combination of properties that were otherwise

only attainable through a more costly secondary process,

such as laminations or coatings.

STEPS OF THE MACHINE DIRECTION ORIENTATION

PROCESS

There are four main steps to the MDO process, as shown

in Figure 1 (3).

Figure 2 is a photograph of a commercial scale MDO

unit and its respective unwinder.

Preheat (PH). The function of the preheat section is to

uniformly heat the ﬁlm to the desired orientation

temperature. This must be done without generating

wrinkles or damaging the surface of the ﬁlm.

Drawing (SD, Slow Draw; FD, Fast Draw). After

preheating, the ﬁlm is oriented between the slow

and fast draw rolls. In this stage, the fast draw roll is

rotating at a speciﬁed ratio faster than the slow

draw roll. The gap between these rolls can be

adjustable to process a wide variety of ﬁlms. Typi-

cally, the ﬁlm can be oriented to as high of a ratio as

10:1 in a single draw section. Higher ratios are

possible, but depend on the equipment’s design,

polymer selection, and ﬁlm structure.

Annealing (A). The third section of an MDO consists

of the annealing rolls. This section thermally stabi-

lizes the ﬁlm’s properties, such as the percentage of

shrink. For example, annealing the ﬁlm at an ele-

vated temperature allows it to relax, minimizing the

PH-1

PH-2

A-1

A-2

C-2

C-1

OUT

Figure 1. Schematic of an MDO. The equipment consists of

preheat (PH), slow and fast draw (SD, FD), and annealing (A)

and cooling (C) rolls. Nip rolls are shown on PH-1, SD, FD, A-1,

and C-2.

Figure 2. Photograph of a commercial scale MDO unit and its

respective unwinder.

685

percent shrinkage when the ﬁlm is exposed to

elevated temperatures, as is the case with the pouch

or bag forming process. Conversely, immediately

cooling the ﬁlm in the annealing section hinders

the relaxation of the ﬁlm. The residual stress in the

ﬁlm causes it to shrink when exposed to elevated

temperatures. This characteristic is desirable in

several applications, such as shrink wrap bundling

and shrink bottle labels.

Cooling (C). The cooling section is the last stage in the

MDO, where the ﬁlm is cooled to near-ambient

temperature for winding.

DESIGN OF THE COMPONENTS OF A MDO LINE

The MDO production line consists of the following compo-

nents (3):

. Unwinder

. MDO unit

. Auxiliary equipment, such as treaters, proﬁle

gauges, and trim collection systems

. Rewinder

Unwinder

An unwinder is used if the MDO is not in-line with ﬁlm

extrusion, such as a blown or cast ﬁlm unit. Often, the

unwinder is very simple; however, more elaborate units

can be utilized that make the process of changing rolls

easier and improve the economics of the process by

decreasing roll change over time. The following items

must be considered when choosing an unwinder:

. Changing rolls needs to be done safely and efﬁciently.

. The unwinder should be able to handle rolls of the

same dimensions as the rewinder.

. Tension control needs to be incorporated into the

unwinder operations to minimize wrinkles as the

ﬁlm enters the MDO.

MDO Unit

While the basic sections of the MDO have already been

discussed, some general comments about each section

must be made.

Preheat Section of the MDO. In the preheat section,

accommodations for the relaxation of the ﬁlm must

be included in the design of the MDO. If the ﬁlm is

heated too fast, wrinkles can form, causing incon-

sistent operating conditions from uneven heating

of the ﬁlm, resulting in unacceptable ﬁlm quality

and/or breaks. If the ﬁlm is heated too slowly, the

necessary orientation temperature will not be

reached, resulting in uneven stretching and possible

breaks.

Draw Section of the MDO. Orientation in the drawing

section must be conducted in a controlled fashion,

with uniform temperatures across the ﬁlm. In addi-

tion, the rate at which the ﬁlm is drawn is critical for

establishing stable operating conditions. Process

parameters, such as orientation temperature, draw

ratio, incoming line speed, and draw gap distance

are all critical for establishing a stable processing

window. Often, it is desirable to orient the ﬁlm to its

maximum draw ratio prior to breaking. To do so, the

preheating temperatures are typically set as high as

possible without melting the ﬁlm to the roll and the

rate of draw optimized to reduce the risk of ﬁlm

breaking. Adverse effects of operating at such con-

ditions include the risk of melting the ﬁlm to the

rolls, which can result in extensive cleaning, and

increasing the amount of neck-in. Large neck-in,

which is indicative of a slow rate of draw, results in

heavier edge beads that must be trimmed. Operat-

ing in such fashion increases the amount of scrap

and can result in downstream web handling issues,

such as wrinkles and poor roll winding uniformity.

In most cases, the draw rolls are smaller in dia-

meter, relative to the other rolls in the MDO, to

minimize the tangential distance between the re-

lease point off the slow draw roll and the inlet point

on the fast draw roll. This design is critical for

minimizing the amount of neck-in. In addition,

with some polymers such as high-density polyethy-

lene, draw resonance or ‘‘tiger striping’’ can be

caused by too low of a rate of draw. This results in

unacceptable ﬁlm that has thick and thin strips in

the transverse direction. Setting the draw gap too

narrow can result in rates of draw that are above

those the ﬁlm can withstand, resulting in undesired

web breaks.

Annealing Section of the MDO. The annealing section

is one of the most important stages within the MDO

for controlling ﬁlm properties. In this section, the

ﬁlm is stabilized at a speciﬁc temperature to provide

a ﬁlm with a desired balance of properties. Inade-

quate annealing can result in ﬁlms with higher

shrink values at a given temperature, lower gloss,

and higher haze values. Such issues can be detri-

mental to many secondary processes, such as pouch

making, where the ﬁlm will shrink once heated,

resulting in an unacceptable seal. Annealing also

reduces the amount of shrinkage on the roll after it

has

been wound. Insufﬁcient

annealing can result in

excessive tensions within the roll, often causing poor

roll proﬁle and edges, blocking, and even crushed

cores. Typically, if the ﬁlm is not designed for a

shrink application, it needs to be annealed to mini-

mize the previously mentioned issues. Annealing is

generally done near the orientation temperatures.

The equipment must be properly designed to allow

for adequate time to properly anneal the ﬁlm prior to

the cooling section, and it is typically done with

several large-diameter rolls.

Cooling Section of the MDO. The function of the cool-

ing section is to uniformly cool the oriented ﬁlm to

near-ambient temperature. It is important to note

686 MACHINE DIRECTION ORIENTATION

that the ﬁlm is shrinking as it is cooled, so great care

must be taken to ensure that wrinkles do not form in

this section. This is done by setting the temperature

proﬁle and individual roll speeds in the cooling

section to allow the ﬁlm to relax in a controlled

fashion. Typically, the cooling section consists of

either a few large-diameter rolls or several smal-

ler-diameter rolls closely placed together.

Auxiliary Equipment

Most MDO lines have a method of treating to increase the

surface energy of the ﬁlm. Such treatment is often neces-

sary for secondary process, such as printing and lamina-

tions. Corona treatment is the most commonly used

technique, but alternatives such as atmospheric plasma

treatment can also be utilized.

A proﬁle gauge at the outlet of the MDO is a useful tool

for measuring the true draw ratio of the ﬁlm, as well as

determining the appropriate location on the width of the

ﬁlm to take edge trim.

Trim collection systems are also necessary in the MDO

process. The simplest technique is to utilize a small trim

winder. While these units can be economical and easy to

use, they do require periodically changing rolls during

production and may not be the most reliable solution.

More elaborate blower systems can be utilized to collect

the trim at the slitting station and pneumatically transfer

it to gaylords, bailers, or compactors. While blowing

the trim is a continuous process, it is more expensive to

purchase, install, and operate, is not as portable, and may

require more maintenance than winders. In addition,

blowing trim into gaylords results in inefﬁcient scrap

management and higher transportation costs.

Rewinder

Selecting a high-quality, versatile rewinder is critical to

the production of high-quality MDO ﬁlms. With the wide

range of physical properties attainable through MDO, a

robust rewinder is absolutely necessary. Inherent issues

with MDO ﬁlm, including post-orientation shrinkage,

heavy edges, and warmer ﬁlm temperatures, may make

it necessary to wind the ﬁlm using low tensions as it comes

off the MDO line. Doing so will allow it to shrink on the

core after it has been oriented and minimize quality

issues.

IMPROVEMENT IN FILM PROPERTIES

MDO greatly improves the mechanical properties of poly-

mer ﬁlms (4–8). Table 1 shows the typical relationships

between the changes in ﬁlm properties as they relate to

increasing draw ratio.

The modulus of the polymer ﬁlm can increase signiﬁ-

cantly with increasing draw ratio (4–6), and in some cases

by 10 times in the machine direction and nearly twice in the

transverse direction (4, 5). Similar magnitudes of change

were seen in the machine direction break strength (4).

Barrier properties also improve signiﬁcantly: The

water vapor transmission rates were reduced by nearly

70% for MDO HDPE (6), and oxygen transmission rates

were decreased by over 40% in LLDPE/tie/EVOH/tie/

LLDPE coextruded ﬁlms (7). In addition, the MDO ﬁlm

had 70% better oxygen barrier at high relative humidity

(90% RH) when compared to the undrawn ﬁlm (7). For

bimodal HMW-PE ﬁlms, the oxygen and moisture trans-

mission rates go through a maximum, relative to increas-

ing draw ratio, prior to decreasing signiﬁcantly at higher

draw ratios (8). More complicated MDO ﬁlms rival the

oxygen and moisture barrier properties of less desirable

coatings and laminations containing PVdC and metalized

ﬁlms (2). These examples demonstrate how MDO can be

used not only to provide high barrier but also to tune the

barrier properties of polymer ﬁlms.

Optical properties improve signiﬁcantly after orienta-

tion. For HDPE, the gloss increased by over 70% while the

haze decreased by nearly 60% at a draw ratio of 6:1 (6). For

LLDPE/tie/EVOH/tie/LLDPE ﬁlm, the gloss increased by

60% and the haze decreased by over 70% at a draw ratio of

6.5:1 (7).

Typically, machine direction tear and dart drop

strengths decrease with increasing draw ratio. Specially

formulating ﬁlm structures can have acceptable tear

strengths for a given application, while obtaining several

of the previously mentioned beneﬁts from the MDO

process (5). Additional work has also shown that through

ﬁlm design, the relationship between dart drop and

draw ratio can be reversed, producing ﬁlms that have

increasing dart drop impact strength with increasing

draw ratio (1).

ECONOMIC BENEFITS OF USING MDO FILMS

Packaging costs can be signiﬁcantly reduced, often with

an improvement in performance, by utilizing MDO ﬁlms.

Three ways that MDO ﬁlms can reduce packaging costs

are (2):

. Downgauging a current ﬁlm

. Replacing less desirable ﬁlms

. Reducing or eliminating additional steps necessary

for the production of a ﬂexible packaging

For the ﬁrst scenario, the improvements in the modulus

can allow a converter to downgauge a ﬁlm used in a

Table 1. Relationship Between Changes in MDO Polymer

Films Relative to Increasing Draw Ratio

Property Change

Modulus Increases

Tensile strength Increases

Barrier (water, oxygen, grease) Increases

Gloss Increases

Haze Decreases

Machine direction tear strength Decreases

Transverse direction tear strength Increases

Dart drop Decreases

MACHINE DIRECTION ORIENTATION 687