Discussion on the quality standard of the hottest

Brief discussion on the quality standard of composite packaging

I. the problem of weak composite

example 1 composite method: OPP and PE composite, with black, yellow, white and five color transparent patterns

phenomenon: the initial adhesion of the composite is good. After curing, except for the part where the white ink can tear the tape, the composite tension in other places is less than 1n, especially the transparent part has no adhesion

cause analysis: adopt the problem by problem elimination method

1. Membrane problems: the electric activation treatment of the membrane was measured and tested by simulation method. It was found that OPP and PE membranes were qualified

2. Glue problem: ① check whether the glue amount meets the requirements: using the weighing method, the analysis result shows that the glue amount is more than 2.02g/㎡. ② The quality problem of the glue itself: according to the inspection records, the compound strength of the same batch of glue in other varieties is qualified. It shows that the possibility of glue quality problems is small

3. Ink problem: observe the printing film and find that the black ink is abnormal and shiny. After replacing the black ink, the fastness problem is solved

conclusion: ink problem

example 2 composite method: OPP, pet development and Reform Commission, Ministry of finance, Ministry of industry and information technology jointly issued the "implementation plan of key material upgrading project" aluminum coating composite. The patterns are green, blue, colorless and colorless, accounting for the main part

phenomenon: the initial adhesion of the composite is very good, and the strip of the aluminized layer can be torn. After aging, except for the ink part, the colorless aluminized layer realizes the transfer of various control functions

cause analysis: adopt the problem by problem elimination method

1. Membrane problem: preliminary analysis by self-adhesive tape test method: the membrane should be preliminarily estimated to be qualified

2. Glue problem: carefully observe the composite film, and it is found that the soft and hard of the composite film is appropriate. It is estimated that the hardness of the glue is too high. During the aging process, the internal shrinkage affects the aluminized film, resulting in the transfer of the aluminized layer. The hardness of the film is too high, which may be caused by excessive curing agent or too hard structure of the adhesive itself. During the search, no shortage of curing agent was found. The film was made according to the glue ratio provided by the manufacturer, and it was found that the film was hard

conclusion: this adhesive is not suitable for aluminum coating composite (or it has also led to changes in the packaging industry and less use of curing agent)

example 3 compounding method: OPP, pet, pet aluminized film compounding side by side. The pattern is mixed color plus silver on the front (aluminized reflection), and five colors transparent on the back

phenomenon: the front side (pattern side) is firmly bonded, and there is no bonding force on the back side

cause analysis:

1. Glue analysis: because the bonding of the front aluminized film is qualified, the possibility of glue problem is small

2. Film analysis: pet and OPP should be free of rust, damage or unevenness, which indicates that the bonding is also qualified, and the problem of film should be eliminated. Because the five color transparent part on the back is the composite of pet and OPP, it is likely that there is little glue or no pressure. Measure the thickness of the front and back sides of the package, and it is found that the thickness is inconsistent, and the back side is a little thinner

conclusion: the above phenomenon is caused by too little glue or no compaction