How to reasonably select composite material, is the key to prepare packing step.
Cooking temperature above 121 ℃ (the market at present
, including aluminum foil of high temperature cooking packaging, mainly has the following two kinds of material structure, namely the BOPET/AL/RCPP and BOPET/AL/BOPA/RCPP.
The following author focuses on analyzing the two kinds of structure, and to discuss with you, hope to do something, and to help you do this kind of packaging well.
Aluminum foil bags 】
BOPET this material mainly polyester (
Slices as the raw material, after biaxial stretching the output of a good performance of high-grade plastic film, which has high transparency, avirulent insipidity, tensile strength, good stiffness, tear resistance, it is not easy broken, excellent electrical and optical properties, good wet, cold resistance of oxygen resistance (
- - - - - -
, heat resistant,
And chemical corrosion resistance and excellent characteristics of contractility and stable.
Choose BOPET heat shrinkage rate should be paid attention to under the condition of 150 ℃, 30 min longitudinal & le;
2%, transverse & le;
5%, and ensure that the surface tension should not be less than 45 mn/m.
Aluminum foil is the only metal foil flexible packaging materials in the class, in the field of packaging has a very long time.
Aluminum foil is the metal material, the resistance of water, gas blocking, shading, flavour is difficult to achieve by any other packaging materials, is the packaging material is still not completely replace.
Aluminum foil is 99.
0% ~ 99.
97% purity aluminium, after many made by rolling, rich in resources, cost performance is quite advantage, cooking packaging aluminum foil shall choose A grade 9 microns thick soft aluminum foil.
Durable thorn BOPA film strength, impact strength, the strength of friction, high bending strength, and good barrier property, we should pay attention to when using BOPA bibulous deformation of the properties which are easily be affected with damp be affected with damp.
As an intermediary material, requiring double-sided corona treatment, surface tension is not less than 50 mn/m, some customers use one-side processing of BOPA compound.
Will be much lower, the strength of compound after increasing the processing the amount of glue to make up for.
RCPP film is characteristic of transparency, good, good flatness, good temperature tolerance, has a certain degree of crisp, not lose flexibility, heat sealing and heat shrinkage rate should be paid attention to do RCPP containing aluminum foil packing don't too big, should consider when select material content of different, targeted to a certain extent, especially in such as do some contents containing fat, acid and alkali substances more should pay attention to the class.
Suggest cooking CPP thickness not less than 80 microns, and to select good suppliers in terms of physical control, select the product for the special requirements of content.
Cooking packaging use ink choose pay special attention to, want to choose good temperature resistance type double liquid polyurethane ink, double liquid polyurethane ink must add curing agent, otherwise, because of free hydroxyl consumes part of the ink curing agent, cause there is not enough curing agent and the main reaction, makes the rubber cannot be completely cured.
After cooking the lighter for low peel strength, sub happened back to stick;
Serious ink layer and the aluminum foil layer would appear, affect the appearance of the packaging and the blocking performance.