上海Appearance requirements when selecting film rolls of Dalian bag-making products

In addition to confirming the production date and shelf life of the external label specification, the following points should be taken as the important requirements for the appearance of the film roll when selecting and purchasing the film roll of Dalian bag-making products:

1) In terms of food safety and hygiene standards, each roll of film is not allowed to have any peculiar smell, even the "resin smell" that is often emphasized by film manufacturers is not allowed, because these peculiar smells will seriously affect the taste guarantee of the contents of packaging bags.

2) The surface of the film roll is not allowed to have serious stripes, nor is it allowed to have sharp ribs, soft wrinkles and dents, because this is the reflection of the uneven accumulation of film thickness, which will lead to irregular slitting end faces, inaccurate overprinting, compound dislocation, coating bubbles or holiday.

3) The surface of the film roll is also not allowed to have crystal spots, black spots, bubbles, dirty spots, oil stains, etc. that have an impact on the quality of downstream products. These will affect the appearance quality and composite quality of downstream products.

4) The film roll is not allowed to be loose inside and tight outside, and it is also not allowed to insert newspapers due to the thickness of the material to achieve surface flatness during slitting. The star-shaped wrinkles on the end surface caused by internal looseness and external tightness are also not allowed, which are caused by improper control of tension reduction during slitting, improper control of tension reduction pressure change or uneven film thickness, bending of paper core, and imbalance of contact roller pressure.