Release papers can be classified according to plastic release paper and non-plastic release paper; it can also be classified according to the release agent as silicone release paper and non-silicone release paper. Plastic release paper, because the release agent has a certain permeability, if there is no certain barrier, the release agent will penetrate into the paper, resulting in poor curing and the use of a large amount of release agent (too high cost) and many other undesirable factors. So the paper needs to be coated with plastic processing (commonly known as lamination), domestic general use of polyethylene (PE) particles for lamination, requiring a melt index of about 7, domestic PE particles are generally used Yanshan Petrochemical 1C 7A. divided into single plastic release papers and double plastic release papers; no plastic release papers, mainly Grassian, CCK and other release papers by special treatment .
After the original paper has been laminated, a release agent is applied to the laminated surface to produce the release papers. As the paper has paper hairs and fibres on the surface, the lamination must be applied to a certain amount to ensure that there are no penetration points, that the silicone oil does not penetrate the paper and that there are no peel-off defects. Theoretically, as long as the tape can be peeled from the release papers, any lower amount of lamination is acceptable. Film laminated release papers are divided into single and double laminated. Generally, single-sided release papers are single laminated, but there are also double laminated single-sided release papers, as the lamination on the release side is generally thicker at 20 grams and the non-release side is generally thinner at 15 grams, which makes the release papers flatter. If the laminate is 22 g on both sides, it is more suitable for double-sided release paper. The laminated release paper is generally made of full wood pulp paper, especially in the electronics industry. If straw pulp paper is used, there will be a lot of paper dust and easily broken edges when die-cutting. Full wood pulp paper is generally known as kraft paper, such as this colour kraft paper (commonly known as: this cattle), white kraft paper (commonly known as: white cattle), yellow kraft paper (commonly known as: Japan yellow coloured cattle), blue kraft paper (commonly known as: Indonesia blue coloured cattle). Of course, there is also a full wood pulp double glue paper as the original paper more with photographic paper as the original paper, as well as with coated paper and white board paper, kraft card, milk card and other paper as the original paper. As long as the fastness of the laminated paper can meet the requirements, as long as the laminated film does not have penetration points and the lamination is even and flat, it should be said that any paper can be used as the original paper.
Grassian paper is produced by supercalendering and then coating with a release agent. Grassian is particularly suitable for die-cutting plants because of its supercalendering and the good tightness of the paper. As domestic Grassian can only produce 60-80 gram quanities, die-cutting plants prefer to use the original paper, but as the starting quantification of the imported original paper is more than 20 tons, such as 120 grams, 140 grams, it has a certain transparency, good stiffness and good die-cutting performance. All of them rely on the input of each container and must be booked 3 months in advance, with full payment required for the order. There are many domestic suppliers of release coating who do not see much point in this.
CCK paper is produced by coating the surface with a special vitrified clay and then coating it with a release agent. Because of its particularly good resistance to high temperatures, it is widely used in the carbon fibre industry CCK raw paper surface clay is very easy to destroy silicone, so the domestic production of CCK release paper can really pass the test is still in the minority.
There are also release papers that are widely used by many industries, as well as those that do not use a release agent. For example, label printers tend to put a varnish on the areas that need to have a release, which will also have some release ability, but of course only if the glue is very weak. Otherwise, this release ability is also in vain. There are other release papers produced using some special glue and other formulations that account for very little of the overall market share. The electronics industry uses less genuine paper (paper produced by regular factories with a guarantee of consistent quality and supply), and is mainly dominated by messy paper (paper that has been used once abroad, or has quality defects). In contrast, the gluing mills basically use genuine paper.