Instrumentation and tools for testing instruments: BMH-J3 film thickness gauge, ts-25c back pressure high temperature cooking pot, LDX-200 universal material testing machine, 2061c gas chromatograph, C-95 sealing tester, incubator, electronics Balance scale, viscosity cup, leaking agent, pressure gauge, steel ruler, corona liquid, stopwatch. Inspection items and methods 1. Inspection of raw materials:
a. Thickness of film (aluminum foil) (according to GB 6672), tensile strength & elongation (performed according to GB 13022-91), wetting tension (performed according to GB 10003-88), oxygen permeability / moisture permeability (according to GB1038/ 1037 Carry out), high temperature resistance, hygienic suitability (in accordance with GB-9687-88), appearance;
b. High temperature resistance of adhesives and inks, food hygiene suitability;
2. Inspection of the film (aluminum foil) compounding process:
a. Appearance (visual defects such as no wrinkles and separation);
b. Compound speed, viscosity of glue:
The measured values ​​are different depending on the binder used and the ratio;
c. Glue test:
Use coated paper (or glossy glossy paper), divided into three different positions of left, center and right, placed in the middle of the two layers of film to be composited. After compounding, remove the sample. Then use a 100mm 100mm area square to cut the sample at three different positions: left, center, and right; then remove the coated paper (or self-adhesive paper) and place the glued film on the electronic scale. Write down the weight a. The weighed film (coated surface with glue) was placed in a solvent (EA) to remove the glue, and then weighed on an electronic scale and the weight b was recorded. Ab is the amount of glue applied to the sample, and then converted into units of g/m2.
d. Control of curing temperature and time after compounding:
According to the different raw materials used, set the corresponding temperature and time;
e. The composite strength between the matured composite films (according to 8808-88); the left, middle and right test pieces were cut, the test piece width was 15 mm, the length was about 15 cm, and the test layer and the layer were peeled apart by about 15 mm. They are fixed on the upper and lower fixtures of the LDX-200 universal material testing machine, and the tensile speed is adjusted to 100mm/min for measurement.
f. Residual solvent amount:
The 0.2 m2 sample was cut, and the sample was quickly cut into 10 mm 30 mm pieces, placed in a clean 500 ml conical flask preheated at 80 ° C, sealed with a silicone plug, and placed in an 80 ° C incubator for 30 min. The gas sample in a 1 ml bottle was injected into a 2061 C gas chromatograph using a 5 ml syringe, and the result was ≤ 10 mg/m 2 as a pass.
3. Inspection of the bag making process:
a. Bag size, edge size specifications (according to customer requirements);
b. Heat sealing strength
Use a steel ruler to cut a 15mm wide test piece from the edge seal of the bag. (Depending on the area of ​​the bag and the shape of the bag, the number and position of the test piece are also different. The length of the sample depends on the size of the bag, and is fixed in The heat seal strength was measured on the upper and lower jigs of the LDX-200 universal material testing machine. )
C Put the equal volume of water into the bag and seal it. Place the bag sample between the upper and lower plates of the pressure gauge. Perform pressure test according to the conditions (pressure, time) required by the customer to observe whether the bag is broken or leaked.
d. The amount of residual solvent (same as the above composite process check item f):
4. High temperature retort inspection:
After the bag is completed, the bag is filled with the same volume of contents and sealed (note: the contents should be similar to the contents specified by the customer, and water or other substances should not be replaced, and the air inside the bag should be discharged as much as possible during sealing. In order to avoid the air expansion during cooking affecting the test effect), put it into the ts-25c back pressure high temperature cooking pot, set the conditions required by the customer (cooking temperature, time, pressure) to test the high temperature retort resistance;
Appearance inspection after cooking: The surface of the bag should be flat, free of wrinkles, foaming, deformation, no separation and leakage; if any of the defects is unqualified.
Typical physical parameters of retort pouch CPP
Including CPP common cooking film (120 ° C) and high temperature cooking film (135 ° C), with dimensional stability and other material compliance at high temperatures, heat sealing strength retention at high temperatures, thickness is generally 60-80um
For example, the typical values ​​of the physical properties of the product are shown in the table.
Typical physical property index (ASTM standard, heat seal strength standard is TAPPI683)
| Index thickness | Tensile Strength
MPa | Elongation at break
% | Heat shrinkage rate%
(120 ° C
5min) | Right angle tear strength
N/mm |
| | MD | TD | MD | TD | MD | TD | MD | TD |
| 70um | ≥40 | ≥25 | ≥450 | ≥500 | ≤1.0 | ≤1.5 | ≥100 | ≥150 |
friction
/
coefficient | Very poor thickness
% | Average thickness deviation
% | Degree of eclipse
% | Gloss
% | Corona treatment strength
mN/m | Heat seal strength
N/15mm |
| Inside/inside | Outside/outside | ≥±5.0 | ≥±1.2 | ≥ 4.0 | ≤75 | ≤ 38 | ≤8.0 |
| ≥0.60 | ≥0.20 |
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