Plastic bag, additionally called “poly bag” made from polyethylene (HDPE: high-density polyethylene, LDPE: low-density polyethylene, MDPE: medium-density polyethylene) is popular anywhere as an economic & helpful provider item. After over a fifty percent of century of growth, now it has a various variety of styles to please individuals’ requirement: tee shirt handle, block head, pass away cut, patch, flexi-loop, clip loop, rigid deal with, duffer, bag on roll … The manufacturing method for every bag is various however there is a simplified summary concerning plastic bag making process with 4 steps: product blending, squeezing out, printing, ending up. click here to contact ecoplas.
1. Product Blending
Polyethylene resin is mixed in a blending machine. Below, the resin will certainly be blended with some additives, such as:
– EPI, D2W (1-2%) to make the bag been degradable.
– Anti-static (1%) to prevent the plastic layers from sticking together, particularly to aid slim LDPE bag to be opened easier.
– Master-batch (4-7%) to make the shade movie: black, white, yellow, red, blue.
– Ultra-violet Inhibitor (UVI) to shield the plastic from ultra-violet radiation. This additive is extremely helpful in farming plastic cover.
2. Squeezing out
After mixing, the blend will be dealt with right into liquified form at heat. It goes out at the shape of a bubble full of amazing air that originates from the air ring. This air stream helps to blow the bubble up & cool the plastic. The action is really important since it can influence the strength, density consistence & transparency of the movie. The bubble undergoes cooling down tower of 25 – 35 feet high. At the top of the tower, it is directed to be squash progressively to create flat shape. The lay-flat movie travels over a variety of rollers. With basic bag, it is frequently printed, sealed & perforated at the same time of extrusion. For difficult bag, it will be moved to next action in the shape of rolls.
Depending on printing design, color numbers, the plastic bag can be dealt with by flexo- printing or gravure-printing. With all-natural printing design, it is best to utilize gravure printing. For basic, small quantity & food call bag, it is far better to utilize flexo-printing.
This procedure includes 3 major actions: reducing, securing & folding. For different kinds of bags, they use appropriate cutting makers. In this step, side gussets, bottom gussets will be made. In this action, the heat temperature, the rate of machine will decide the strength & the look of the seal. The cut-out part of die cut bag, patch take care of bag, t-shirt bag will be gathered & recycled for trash can. For bags with handle: clip loophole, stiff, soft-loop, they have one more step of handling. With buying square bottom bag, users additionally call for cardboard to make bag strong & in a good shape.