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Advantages of Coroplast Plastic Containers

Lightweight

Usually designed to ship flat when empty

Inert to nearly all acids, chemicals, detergents, grease & oils

Withstands temperature extremes from 17F to 230F

Decreases product damage better than corrugated paper

Greatly reduces shipping costs

Sanitary & maintenance free durability, maintains near new appearance for years

100% recyclable and environmentally friendly

Additional properties of flame retardant, UV inhibitors and ESD protection

Corrugated Comparison Tests

Test Parameters

The tests were conducted at a temperature of 72 degrees Fahrenheit with 50% relative humidity. The test

samples were standard 4mm (150lb) polypropylene corrugate and 250 lb. Test c-flute (cardboard)

corrugated paperboard. No additives such as flame retardant or extra ultra violet protection were in the

samples tested.

PROPERTIES PLASTIC CORRUGATE PAPER CORRUGATEWeight for test 0.15 lbs. / sq. ft. 0.15 lbs. / sq. ft.Water Absorption in 24 hrs 0.02% 75%Edge Crush Test 45 lbs. sq. ft. 5 lbs. sq. ft.Flat Crush Test 80 lbs. / sq. inch 3 lbs. / sq. inchTear Strength 1700 grams 10 gramsTensile Strength 4,000 lbs. / sq. inch 200 lbs. / inchImpact Dart Test 320 inches / lb. 32 inches / lb.

Heat Def. Load @ 66 lbs. per sq. inch 174 degrees Not ApplicableLiving Hinge 21,000 cycles 1,000 cycles

Test Comparison Comments

The test results of same weight equivalent materials indicates that the plastic corrugate performance

exceeds, in every area, the performance of the corrugate paper (cardboard). This is especially true in the

areas of the heat deflection load at 66 lbs. / sq. inch. All strength test properties areas indicate a minimum

ten-fold advantage (edge crush) with the plastic corrugate over the paper corrugate. In some instances the

plastic corrugate has a 3,750 fold (water absorption) advantage. It is also important to remember that

comparison does not test contamination issues of the paper corrugate versus the plastic corrugates' inert

properties associated with chemicals, acids, detergents, greases and oils. However, the result of the water

absorption test does give a hint of the expected test result of absorption of acids, chemicals, greases and

oils. Thermal and hinge tests are an area that have unique properties addressed only by the plastic

corrugate. Overall, the end result is corrugated plastic packaging protects your products better than

corrugated paper.

Packaging with Coroplast

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Technical Bulletin - CSS-004-93

Coroplast strength and durability have no direct relationship to corrugated fiberboard.

The figures provided are offered as a guide and may vary with resin batch and production quality of the

finished container.

The USAF has established a specification MIL-P-83668 (USAF) for plastic corrugated packaging

applications.

Stacking

Actual stacking loads on corrugated fiberboard cases are normally recommended to be the compression

strength divided by a factor of 1.5 to 4.5, depending on the intended storage conditions. Tests on

Coroplast would indicate that a factor of 2.5 - 3.5 will probably be adequate over normal temperature

ranges.

Extreme high temperatures will certainly have a negative effect on the stacking strength of Coroplast

boxes while very cool temperatures will increase the strength. Humidity will not cause any change in

Coroplast performance.With corrugated fiberboard, the drop off in strength as humidity increases is dramatic.

A major performance test series has not yet been performed on Coroplast boxes. Some independent

preliminary test results are offered as a point of reference.

Compression of Other Weights/ Densities of Coroplast 10"x10"x10" Taped RSC

Thickness Weight Compression Average of 64.0 mm 600gm//m(2nd power) Black 496 lb sq. in.4.0 mm 775gm//m(2nd power) Natural 598 lb sq. in.4.0 mm 800gm//m(2nd power) White 786 lb sq. in.4.0 mm 800gm//m(2nd power) Natural 694 lb sq. in.4.0 mm 1000gm//m(2nd power) Natural 1040 lb sq. in.

5.0 mm 1000gm//m(2nd power) Natural 1272 lb sq. in.5.0 mm 1000gm//m(2nd power) Blue 1567 lb sq. in.

Rough Handling

The rough handling characteristic of Coroplast compare well against fiberboard. Tests have shown that

Coroplast has significantly higher burst, puncture, and edge and flat crush properties that B flute

fiberboard.

Bursting Strength

Coroplast will not burst on the Mullen Tester.

Puncture

Test show puncture (Beach Impact) 3-4 times higher than corrugated fiberboard of similar stacking ability.

Impact Strength - lbs/sq.in.

Degrees F 2.0mm/ 400gm 4.0mm/ 700gm 4.0mm/ 775gm 5.0mm/ 1000gm74 5302 90.7 97.9 126.532 5.0 88.5 100.3 129.4-4 37.8 62.7 69.4 89.6

Cushioning

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Cushioning test show that prior to complete crushing of the Coroplast flutes, the peak decelerations are in

the range of 150-400 gms. The acceleration time pulses show that even when fully crushed on the

preceding crop, the Coroplast fluting still resists subsequent compression and provides cushioning

Coroplast is less easily compressed under both static and dynamic conditions than fiberboard. A higher

stress is needed to crush the flutes and a higher energy is absorbed. This would indicate that Coroplast

will cushion slightly heavier weights from higher drops.

Test Comparing

10"x10"x10"x R.S.C.-- Plastic Tape Joint

Standard conditioning for 24 hours.

A. Fiberboard

B. Coroplast

CRACKING OF FLUTES

One of the problems faced by the corrugator is cracking of flutes.This can occur in two ways.

Cracking along the entire length or cracking at ends.Along entire length

Causes Solutions

Paper is brittle Paper should be tested to ensure that it is not brittle

Excess pressure on flute rollsReduce the pressure of the flute rolls by adjusting the

handwheels

Excess tension on paper roll due to tight brakes

being tight

This tension can be reduced by slightly loosening the

brake

This defect occurs in the corrugating machine due to flattening of flutes rolls, at the ends.

At ends

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Causes Solutions

Continuous use of smaller width paper on a machine

designed for bigger width. The teeth at the ends

experience metal - to - metal contactand get flattened

over a period of time. Now if you use bigger width

paper on this machine, there will be cracking

Regrind the flute roll

LEANED FLUTES

Corrugations ar found leaning or tilted to one side but are otherwise well formed.

Causes Solutions

Non-alignment of machine Check and correct the alignment of machine.

Sometimes the bushes of the flute roll worn out and

become loose. There is thus a play between the

roller and the bush. This disturbs the alignment of

the flute roll.

Replace the bushes.

HIGH AND LOW FLUTES

One of the problems faced by the corrugator is cracking of flutes.This can occur in two ways.

Cracking along the entire length or cracking at ends.

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Causes Solutions

Charactestics of paper

With the same setting, when paper from different mills are

used, some qualities of paper may lend to high - lows, where

as with some others, the problem may not occur.

Dirty corrugating rolls Clean the corrugating rolls.

Tension on corrugating medium mat be too loose or too

tightAdjust the brake accordingly.

Cold corrugating rolls Increase heat to the required temperature.

HIGH LOWS

The contact between the flute rolls and the adaptor

should be uniform. It is best to have a gap of 3 - 4

thou between the flute roll and adaaptor to get

proper fluff off.

Causes Solutions

Improper setting of adaptors. Set the adaptors properly

Use of imperfect hand - made file cut adaptors

whose inside curvature is not uniform (an essential

requirement).

Use good quality machine made adaptors.

Worn out of flute rolls Regrind the flute rolls

CRUSHED FLUTES

Crushed flutes in some areas of the sheet may occur due to improper setting of adaptors.

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Causes Solutions

If the bottom portion of the adaptor is away from the

flute roll, the fluted peper gets free from the flute roll

prior to reaching nip between flute roll and the

pressure rolls and this portion of the flute getscrushed.

Reset the adaptors with uniform contact with the flute

roll.

When above problem persists after resetting of

adaptor, it indicates worn - out adaptors.Replace the adaptors.

DELAMINATION

Delamination is the common problem.

Sometimes, when higher grammege paper is used, the heat may become insufficient. in such a case ,

speed of the machine shouls be reduced or a higher capacity heater must be installed.

Causes SolutionsIf the bottom portion of the adaptor is away from the

flute roll, the fluted peper gets free from the flute roll

prior to reaching nip between flute roll and the

pressure rolls and this portion of the flute gets

crushed.

Reset the adaptors with uniform contact with the flute

roll.

When above problem persists after resetting of

adaptor, it indicates worn - out adaptors.Replace the adaptors.

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