What is a glassine paper bag?

Greaseproof Paper bag is a kind of pure paper packaging bag without plastic Because of its unique appearance and feel, it makes the greaseproof paper bag feel more premium. 。 Shunxingyuan Packaging will carefully introduce Greaseproof Paper bag the manufacturing process, so as to understand why greaseproof paper bags are in great demand. 。

1、 What is greaseproof paper? paper ？

When it comes to paper, one might not immediately think of paper's transparency. But greaseproof paper is a smooth, glossy semi transparent paper. Greaseproof paper can allow the inner products to show through. Greaseproof paper 's pH value is neutral and acid-free, and it is resistant to moisture, air and grease. Also because greaseproof paper is made from wood pulp, it is completely recyclable and biodegradable, making it a sustainable environmentally friendly material choice.

2 How is greaseproof paper made?

Greaseproof Paper is made from hardwood wood made 's mainly including poplar, oak, birch and gum. Once the trees reach a certain size, the raw wood is harvested, debranched and pruned, and then cut for transport. When the logs arrive at the paper mill, they are completely debarked and sent to a chipper, where they are chipped 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). The pulping process involves cooking wood chips in various ionic solutions to break the chemical bonds of lignin (an organic polymer that forms cell walls and supports plant tissues). This process separates the pure cellulose fibers from lignin and other substances.

Removing all lignin from the fibers during pulping is a key step in making Greaseproof paper. If lignin remains in the pulp during bleaching, the chemical reaction with the bleaching agent will convert the lignin into hydrochloric acid, which over time will make the paper brittle and discolored. By removing lignin, the pulp produces paper with a neutral pH value 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 required grade and color before entering the paper machine. There, the watery pulp flows onto a moving wire mesh, and most of the water drains through the wire mesh. As the paper begins to form, the fibers intertwine. When the wet lump passes through a series of rollers, more water is squeezed out of the wet lump lump.

Calendering is the final step in the papermaking process. By pressing the paper between hard calender rollers or rolls (called a calender), the surface of the paper can be made smooth. Greaseproof paper achieves its unique smooth, semi transparent and glossy properties through supercalendering. This process is done by repeatedly calendering the paper, or more commonly by pressing it on a special machine with heated or cooled pressure calendering rollers.

Meanwhile, the supercalendering process destroys the capillaries of the paper fibers, which gives the paper a highly closed surface with higher density and very low porosity. Therefore, supercalendering makes greaseproof paper resistant to grease, air and moisture.

Many paper bags contain coatings or laminates to achieve these protective effects. laminates And silicone coatings are usually not biodegradable.

3 How to Greaseproof turn paper into greaseproof paper bags?

From Greaseproof paper to greaseproof paper bags, generally requires processes such as slitting, printing, bag making, and packaging. Shunxingyuan Packaging can use various slitting machines to accurately slit the custom sizes required for greaseproof paper bags, and can use rotogravure printing and offset printing Two methods precisely reproduce customer designs on glassine paper, and a patented, high-efficiency glassine bag production machine ensures a continuous supply of high-quality glassine bags.