What is the process of producing express bags?

1. Production process

2. Printing

Gravure printing: refers to the text and pattern on the original manuscript made into a printing plate, coated with ink on the surface of the printing plate, and transferred the text and text on the printing plate to the surface of the printed material through pressure, accurately and in large quantities to copy the same print as the original.

There are different printing methods of table printing and inside printing.

3. Recombination

The basic principle of plastic composite flexible packaging: Each material has different advantages and disadvantages, and the two or more layers of materials are bonded together through the media (such as glue), so that the packaging film and bag achieve better performance technology. This technology is called "composite process" in the production process.

4. Maturation

The purpose of curing is to speed up the rate at which the glue cures between materials.

5. Cut

Cut the printed and composite materials into the specifications required by customers.

6. Make bags

The printed, composite and slitted materials are made into all kinds of bags required by customers.

Can make a variety of bag types: middle bag, side bag, upright bag, K bag, R bag, four side bag, zipper bag.

7. Quality control

(1) Testing of raw materials before storage

(2) Product online testing

Print inspection - residual solvents, sets, etc

Composite inspection - composite strength, bubbles, wrinkles, etc

Bag inspection - sealing strength, size deviation, etc

(3) Product inspection before shipment

8, commonly used printing materials

BOPP

Biaxial tensile polypropylene, it is formed after biaxial tensile film, no heat sealing performance, commonly used as printing materials, because of its superior moisture resistance, suitable for easy moisture absorption of biscuits, cold fruit, puffed food, sunflower seeds and other surface printing materials.

KOP

The bidirectional polypropylene coating is coated with a layer of about 1-2um polyvinylidene chloride (PVDC, also known as K coating) on the OPP surface, so KOP has both OPP performance and PVDC advantages. It is often used in mooncakes and other foods that need to be insulated from oxygen and water. KOP has a barrier function similar to aluminum thin, but also transparent, can see the packaging contents.

PCO

The bidirectional heat sealing polypropylene film has the performance of OPP and the performance of double-sided heat sealing; Often used in disk, seaweed packaging.

PL

The bidirectional heat sealing polypropylene pearl-coated film is made of polypropylene resin as the main raw material, and a certain amount of pearl-coated powder is added. Used for packaging cosmetics, soap, labels, etc.

PET

Polyester film

Like OPP, it is a two-stage bidirectional stretch film that is laterally stretched after longitudinal stretching, or a stretch film that is simultaneously stretched vertically and horizontally and then thermally fixed. Commonly used as machine packaging film, high temperature cooking bags, zipper bags and other products printing materials.