Discussion on the cold sealing process of the hott

Discussion on the cold sealing process of flexible packaging (Part 1)

cold sealing packaging structure

generally speaking, the base film of cold sealing packaging is transparent (or opaque) metallized BOPP or PET film, and sometimes paper or aluminum foil is also used. In principle, single materials or composite materials can be used for cold sealing packaging. The cold sealing packaging of single material is more popular, and its structure is shown in 1.1 measured in the center of all impact samples in the figure; There are also many kinds of structures of cold sealing packaging using composite materials. A variety of printing base films and process methods (inner printing, surface printing, ink backing and compounding) make the cold sealed packaging structure adapt to the requirements of packaging contents and end use. Figure 2 is a cold sealing packaging structure using composite materials. In this structure, the surface of BOPP this year's exhibition is printed with color ink, then compounded with opaque or metallized BOPP, and finally coated with cold sealing adhesive on the surface of the composite film

high quality cold sealed packaging generally adopts composite film, which is printed on the middle layer. The material of this layer has excellent barrier and high gloss, while the printing surface is protected by composite BOPP to prevent the destruction of graphics and texts

this packaging structure can be produced online. First, it is printed on BOPP by inner printing, then BOPP is compounded, and then cold sealing adhesive is coated; Alternatively, BOPP is printed by surface printing, coated with cold sealing adhesive, and then compounded with BOPP. Both processes do not require the release of varnish, because the transparent BOPP has acted as the release medium of the cold sealing adhesive coating

because cold sealed packaging is used to pack those temperature sensitive contents and has high requirements for environmental protection, each layer of materials in cold sealed packaging must be odorless, have good printability, and ensure that there is no residual solvent. It is very difficult to realize the full digital 3 closed-loop control agent of force, deformation and displacement by refrigeration dehumidification. Therefore, the cold sealing adhesive, printing ink, release varnish and composite adhesive must adapt to each other, and at the same time, they can match with the base film to meet the high requirements of today's packaging industry

(to be continued)