What Is A Glassine Paper Bag?

2024-05-23

Author : wing Update Time：May 23 , 2024

【 Abstract 】 :

Glassine paper bag is a pure paper plastic-free packaging bag, because of its unique appearance and touch, so that glassine paper bag texture is more high-quality. Let Goolien Packaging take you through the manufacturing process of glassine paper bags to understand why glassine paper bags are in great demand.

1. What is glassine paper?

When you think of paper, the transparency of paper may not immediately come to mind. But glassine paper is a smooth, glossy, translucent paper. glassine paper allows the product inside to show through. glassine paper is pH neutral and acid free, and is resistant to moisture, air and grease. And because glassine paper is made from wood pulp, it is fully recyclable and biodegradable, making it a sustainable and environmentally friendly material of choice.

2. How is glassine paper made?

Glassine paper is made from hardwood wood, mainly aspen, oak, birch and gum. Once the trees have grown to a certain size, the raw wood is cut down, stripped of branches and twigs, and then cut for transport. When the logs arrive at the mill, they are completely peeled and sent to the chipper, where they are cut into pieces for mechanical or chemical pulping.

The first step in the papermaking process is to convert trees into pulp (the fibrous raw material used to make paper).During the pulping process, wood chips are cooked in various ionic solutions to break the chemical bonds (Organic polymers that form cell walls and support plant tissues) of the lignin. This process separates pure cellulose fibers from lignin and other substances.

Removing all lignin from the fibers during the pulping process is a key step in making glassine paper. If lignin remains in the pulp during bleaching, a chemical reaction with the bleach converts the lignin to hydrochloric acid. Over time, hydrochloric acid makes the paper brittle and discolored. By removing lignin, pulp produces paper that has a neutral pH and is more resistant to changes in chemical, structural or optical properties.

The remaining wood fibers can now be bleached and further treated with dyes, pigments or additives to suit the desired grade and color before going into the paper machine. There, the water-containing pulp flows onto a moving wire cloth, through which most of the water is discharged. As the paper begins to form, the fibers intertwine with each other. As the wet clumps pass through a series of rollers, more water is pushed out of the wet clumps.

Calendering is the last step in the papermaking process. By pressing the paper between hard rollers or rollers (called calenders), the surface of the paper can be smoothed. glassine paper is supercalendered to obtain its unique smooth, translucent and glossy properties. The process is done by putting the paper through the calender process several times, or more commonly by pressing it on a special machine with a heating or cooling pressure calender.

At the same time, the super calendering process destroys the capillaries of the paper fibers, which gives the paper a highly enclosed surface with higher density and very low porosity. As a result, super calender makes glassine paper resistant to oil, air and moisture.

Many paper bags contain coatings or laminates to achieve these protective effects. Laminating and silicone coatings are generally not biodegradable.

3.How to change from glassine paper to glassine paper bag?

From glassine paper to glassine bag, it is generally necessary to go through the process of slitting, printing, bag making, packaging, etc. Goolien Packaging can use a variety of slitting machines to accurately cut glassine paper bags to the required custom sizes. Using two printing methods, intaglio printing and offset printing, we can accurately print patterns on glassine paper and restore customers' designs. We have efficient glassine paper bag production machines with patented design, which ensure a continuous supply of high quality glassine paper bags.