Analysis of the difference between release paper and release film

Release film release paperThere is a significant difference between two things with just one word difference. Release film is a type of silicone release agent applied to the surface of environmentally friendly materials such as PET, PE, and OPP film, allowing it to exhibit extremely light and stable release force for various organic pressure-sensitive adhesives.

Different organic pressure-sensitive adhesives, such as hot-melt adhesives, acrylic adhesives, and pressure-sensitive adhesives for rubber systems, require different release forces for the release film. The adhesive properties of the product adhesive need to be isolated, and the release force should be adjusted accordingly to achieve extremely light and stable release force during peeling.

Release film classification can be divided into different substrates: PE release film, PET release film, OPP release film, composite release film (i.e. the substrate is composed of two or more composite materials), etc.

Single sided release film: HDPE (low pressure polyethylene) release film, used for sealing tape and other waterproof rolls, LDPE (high pressure polyethylene) release film. BOPP (stretch polypropylene) release film for mechanical product packaging, hot melt adhesive packaging, hygiene and nursing products (diapers), anti-corrosion rolls, etc., used for PET (stretch polyester) release film such as sealing tape and silent tape. Double sided release film with adhesive protection, made of red/green polyolefin (PE).

Double sided release film: Used for transparent PET double-sided release film on foam tape; Double sided adhesive sun resistant isolation film (HDPE silver coated film); Reinforced aluminum plated base material BOPP (BOPET) for waterproofing membrane, sun protection and cooling.

The classification of release paper can be divided into plastic release paper and non plastic release paper; Organic silicone release paper and non silicone release paper can also be classified according to release agents. There is plastic release paper, because the release agent has a certain permeability. If there is no certain barrier, the release agent will penetrate into the interior of the paper, causing poor curing and excessive use of release agent (high cost) and many other adverse factors.

So it is necessary to apply plastic coating (commonly known as film coating) on paper. Polyethylene (PE) particles are generally used for film coating in China, with a melt index of around 7. Domestic PE particles are generally selected from Yanshan Petrochemical's 1C7A. Divided into single plastic release paper and double plastic release paper, non plastic release paper, mainly other release papers that have undergone special treatment such as Gracin and CCK.

The release paper produced by laminating the base paper with a film

Due to the presence of paper wool and fibers on the surface of the paper, a certain amount of coating must be applied to ensure that there are no penetration points, that silicone oil does not penetrate into the paper feed, and that there are no peeling defects.

Film coated release paper is divided into single coating and double coating. Generally, single-sided release paper is single coated, but there are also double coated single-sided release paper because the coating on the release surface is thicker, usually 20 grams, and the non release surface is thinner, usually 15 grams. Such release paper is relatively flat. If the double-sided coating amount is 22 grams, it is more suitable for making double-sided release paper.

Generally, all wood pulp paper is used for laminating release paper, especially in the electronics industry. If straw pulp paper is used, there will be a lot of paper scraps and easily broken edges during die-cutting. Full wood pulp paper is generally referred to as kraft paper, such as natural kraft paper (commonly known as "Ben Niu"), white kraft paper (commonly known as "Bai Niu"), yellow kraft paper (commonly known as "Japanese yellow colored kraft paper"), and blue kraft paper (commonly known as "Indonesian blue colored kraft paper").

Gracin release paperRelease paper produced by coating release agent after overpressure

Gracin is particularly suitable for use in die-cutting factories due to its excellent compactness after undergoing super calendering. Due to the fact that domestic Gracin can only produce quantitative quantities of 60-80 grams, die-cutting factories prefer to use quantitative quantities of over 100 grams, such as 120 grams and 140 grams. It has a certain degree of transparency, good stiffness, and good die-cutting performance. All rely on imported raw paper, but the minimum weight for imported raw paper is 20 tons per container, and it must be pre ordered 3 months in advance.

CCK release paper is a release paper produced by coating a special layer of clay on the surface and then applying a release agent

Due to its excellent high-temperature resistance, it is widely used in the carbon fiber industry. The clay and easily damaged organic silicon on the surface of CCK base paper, so only a few domestically produced CCK release papers can truly pass the standards.