Discussion on Quality Standard of Composite Packaging

First, compound problems

Example 1 Composite mode: opp and pe composite, patterns are black, yellow, white, five-color transparent.

Phenomenon: The composite tack is good. After aging, except that the white ink can tear the tape part, the composite tensile force is less than 1n in other places, especially the transparent part has no tackiness.

Analysis of the reasons: Take a problem-by-question elimination method.

1. Membrane problem: The electrical activation of the measurement membrane was tested by simulation and it was found that the opp and PE membranes were qualified.

2. Problems with glue: 1 See if the amount of glue meets the requirements: By using the weighing method, the amount of glue on the analysis result is above 2.02g/m2. 2 The quality of the glue itself: After investigation, it was recorded that the same batch of glue was qualified in composites of other varieties. It is unlikely that there is a quality problem with glue.

3, the ink problem: the printed film was observed and found that the black ink is abnormal, shiny, replace the black ink, the fastness problem is solved.

Conclusion: Ink problem.

Example 2 Composite method: opp, pet aluminum film composite. The pattern is green, blue, colorless, and colorless.

Phenomenon: The initial adhesion is very good, and the aluminum plating layer can be stripped. After the aging, the aluminum plating layer is transferred except for the ink portion.

Analysis of the reasons: Take a problem-by-question elimination method.

1. Membrane problems: Preliminary analysis using the adhesive tape test method: Membrane should be initially evaluated as qualified.

2. Problems with glue: After careful observation of the composite film, it was found that the composite film is suitable for soft and hard. It is estimated that the hardness of the glue is too high. During the maturation process, the effect of internal shrinkage on the aluminum plating film results in transfer of the aluminum plating layer. The hardness of the film is too high, which may be caused by excessive curing agent, or the structure of the glue itself is too hard. In the course of the search, no shortage of curing agent was found. The film was made from the glue ratio provided by the manufacturer and it was found that the film was hard.

Conclusion: This glue should not be used as aluminized composite (or reduced hardener trial).

Example 3 Composite method: opp, pet, pet side-by-side aluminum composite film. The pattern is positively mottled with silver (aluminized reflection) and the back is colored transparent.

Phenomenon: Adhesion on the front (patterned surface) is firm and there is no adhesive force on the reverse side.

Cause Analysis:

1. Analysis of glue: As the adhesive of the frontal aluminized film is qualified, the problem of glue is less likely.

2. Membrane analysis: A separate composite of pet and opp indicates that the adhesion is also acceptable and membrane problems should be excluded. Because the reverse part of the colored transparent part is the combination of pet and opp, it is likely that there is little or no pressure on the glue, and the thickness of the front and back sides of the package is measured. As a result, the thickness is found to be inconsistent and the reverse is slightly thinner.

Conclusion: The above phenomenon is caused by too little glue or no compaction.