Silica gel release agent is applied to the surface of environmental protection materials such as PET, PE and OPP film, which can show very light and stable release force for various organic pressure sensitive adhesives.
Different organic pressure-sensitive adhesives, such as thermal melt adhesives, acrylic adhesives and pressure-sensitive adhesives of rubber systems, etc., require different separating force of the release film. The needle needs to isolate the adhesive of the product with different stickiness, and the separating force should be adjusted accordingly so as to achieve extremely light and stable separating force during peeling.
Classification of release membranes
Different substrates can be divided into PE, PET, OPP, and composite membranes (i.e., the substrates are made of two or more materials).
According to the release force, it can be divided into light detachment type, middle separation type and heavy release type.
According to the color, it can be divided into red, yellow, green and blue PET film.
According to the surface treatment, it can be divided into single-sided, double-sided, silicon-free, fluoroplastic, single-sided, double-sided, abrasive, matte, etc.
One-sided parting film: HDPE (low-pressure polyethylene) parting film: LDPE (high-pressure polyethylene) parting film for sealing tape and other waterproof rolls: mechanical product packaging, hot-melt adhesive packaging, health care products (wet urine), anti-corrosion rolls and other BOPP (stretched polypropylene) parting film: PET for sealing tape, silent tape, etc. (stretch polyester) release film: back glue protection, etc.
Double-sided parting film: red/green polyolefin (PE) double-sided parting film: used for foam tape transparent PET double-sided parting film: double-sided adhesive anti-sunshine isolation film (HDPE silver coating film): waterproof roll sunscreen cooling reinforced aluminum-plated base material BOPP (BOPET): improve the adhesion of the aluminized layer, so that 100 ~C cooking according to material, use It can be divided into: silicone oil film/ionized film-polyester film (PET) protective film, polyester film, pre-coating film, light diffusion film, color inkjet film (computer film), special printing film for electronic industry, abrasive film, drawing film, white polyester film, black polyester film, PET polyester film\ PET Mylar.
I'll show you the release paper.
Release paper, also known as silicone oil paper, anti adhesive paper. It mainly acts as an isolating object, such as adhesive tape. Generally, it needs to be stripped and discarded when it is used. Now it is widely used, mainly as the carrier of tape or tape products. Of course, the application in food, medical and health industry is not described in detail here.
Classification of release paper
Separation paper can be classified into plastic paper and non-plastic paper. Organosilicon paper and non-silicon paper can also be classified according to separating agent.
There are plastic separating paper, because the separating agent has a certain permeability, if there is no certain barrier, the separating agent will penetrate into the inside of the paper, resulting in poor curing and the excessive use of separating agent (high cost) and many other adverse factors. Therefore, it is necessary to do plastic coating on paper (commonly known as shower film). In China, polyethylene (PE) particles are generally used for shower film. The melting index is about 7. Domestic PE particles are generally selected as 1C7A of Yanshan Petrochemical Company. It can be divided into single plastic release paper and double plastic release paper. Non-plastic release paper mainly includes Grassin, CCK and other special treated release paper.
1. film release paper
After the original paper is coated, the release agent is coated on the film surface to produce the obtained release paper.
Because the paper surface has paper wool and fibers, so the film must reach a certain amount to ensure that there is no penetration point, to ensure that silicone oil will not penetrate into the paper, in order to ensure that there will be no bad peeling. Generally, the amount of film-spraying paper is 16 grams per square metre. It is said that Wenzhou has achieved 11-13 grams per square metre, which is quite close to the data of advanced equipment abroad. Theoretically, as long as the adhesive tape can be stripped from the stripped paper, the lower amount of film is permitted.
The paper is divided into single shower and double shower. Generally, one-sided release paper is single-drip, of course, there are also double-drip one-sided release paper, because the release surface is usually 20 grams thick, and the non-release surface is generally 15 grams thin, so the release paper is relatively flat.
If it is double-sided film coated with 22 grams of film, it is more suitable for double-sided release paper.
Generally, all types of paper are selected from all kinds of wood pulp and paper, especially in the electronics industry. If straw pulp paper is used, there will be a lot of paper scraps and easy to cut edges when die-cutting.
Whole wood pulp paper is generally called kraft paper, such as natural kraft paper (commonly known as Ben Niu), white kraft paper (commonly known as white cow), yellow kraft paper (commonly known as Japanese yellow cow), blue kraft paper (commonly known as Indonesian blue cow).
Of course, there are also two kinds of base paper made of full wood pulp, photographic paper, copperplate paper and white board paper, cow cards, milk cards and so on.
As long as the paper-plastic fastness of the shower film can meet the requirements, as long as the shower film has no penetration point and the shower film is even and flat, what paper should be said can be used as base paper.
2. gram shaped release paper
Grasin's base paper was coated with release agent after overpressure, and the release paper was produced.
Grasin is very suitable for die cutting plants because of its super compaction.
Since domestic Grassin can only produce 60 to 80 grams of quantities, die-cutting factories prefer to use more than 100 grams of quantities, such as 120 grams, 140 grams. It has a certain degree of transparency, good stiffness and good cutting performance. All rely on imported base paper, but since the starting quantity of imported base paper is 20 tons per container, and must be booked three months in advance, the order must be paid in full. There are many off the shelf coating suppliers in China that do not have much significance.
3.CCK release paper
CCK base paper is coated with a special layer of clay and coated with release agent.
Because of its excellent high temperature resistance, it is widely used in the carbon fiber industry.
Ceramic clay on the surface of CCK base paper and organosilicon are easy to be destroyed, so few CCK paper produced in China can really pass the customs.
4. other release paper
In addition, some release paper is widely used in many industries, and there is also no use of release agents. For example, label printing plants often have a layer of varnish on the place where they need to be separated. They also have a certain ability to separate. Of course, the performance of glue is very weak. Otherwise, the ability to cast off is useless. Others use some special glue and other formulations to produce the release paper, which accounts for a small market share.
At present, the electronic industry uses less genuine paper (separated paper with stable quality and supply guarantees produced by regular factories), mainly random-coded paper (used once abroad, or separated paper with quality defects).
The glue factory basically uses the genuine paper.
The main type separating agent is organosilicon type separating agent, and the secondary is organofluorine type separating agent and some other non-silicon type separating agent.
The main contact glue of silicone release paper is hot sol, oil acrylic pressure sensitive adhesive (commonly known as oil glue) and emulsion acrylic pressure sensitive adhesive (commonly known as water glue).
Fluorocarbon release paper mainly contacts silicone pressure sensitive adhesive (commonly known as silica gel).
Organosilicon ionizers can be divided into solvent-based and solvent-free types or into heat-cured silicone oil, UV-cured silicone oil and electron beam-cured silicone oil according to curing methods.
Solvent-based silicone oil accounts for more than 60% of the total paper market. However, due to the recent soaring oil prices, the cost of solvent has increased, and many enterprises have begun to turn to solvent-free silicone oil.
Solvent-based silicone oil coating cost is the lowest, for example, oil glue K-50, dry glue 60 grams, need to coat solvent-based dry silicone coating amount of 0.80 grams per square metre, if using solvent-free dry silicone coating amount must be 1.30 grams per square metre. Many off-type coating suppliers have added solvents to solvent-free silicone oil to reduce the content of silicone due to equipment limitations and to reduce coating costs, so as to reduce the amount of coating, the risk is considerable. And solvent free silicone oil is not suitable for oil glue.
Because silicone oil needs to be volatilized and cured at a certain temperature, the most commonly used silicone oil is heat cured silicone oil. Of course, many domestic manufacturers have used UV curing, which is mainly used in film coating. Because the film can not withstand the curing temperature, UV curing is generally used as a relatively expensive curing method, regardless of equipment investment or processing costs. UV curing is double to two times that of thermal curing.
Electron beam curing is currently only used by the manufacturer of leather separating paper. It is known that this equipment is available in a foreign manufacturer in China.
Technical specifications of release paper
The technical indexes of release paper are as follows: dry silicon coating amount, normal temperature peeling force, aging peeling force and residual adhesion rate.
The amount of dry silicon coating is that the amount of the material applied to the material is per gram per square meter. Generally, the coating amount of solvent-based silicone oil ranges from 0.30 to 0.80 grams per square metre, and that of solvent-free silicone oil ranges from 0.80 to 1.30 grams per square metre. Professional testing equipment is needed to test the coating amount.
The amount of silicone oil coating directly affects the peeling performance. The higher coating amount can cover the base paper densely and ensure the uniform distribution of silicone oil. While the lower silicone oil coating amount is prone to leakage and coating, resulting in poor peel. Some off-type coating suppliers to reduce the amount of silicone oil coating, resulting in heavy peeling, the production of off-type paper, when used, is quite risky.
Reliable manufacturer realizes peeling force adjustment by adjusting chemical formula without reducing the amount of silicone oil coating. It takes a considerable amount of time to accumulate technology, rather than achieving it overnight.
Peeling force at room temperature, the peeling force data obtained by standard test method at room temperature, unit N/25mm, can be converted into how many grams.
The general 0.10N/25mm is the peel force below 10 grams, commonly known as light peeling.
0.20N/25mm is the peel force below 20 grams, commonly known as the middle peel.
0.35~0.45N/25mm, that is, the stripping force of 35~45 grams, commonly known as re stripping;
0.60~0.80N/25mm, that is, the stripping force of 60~80 grams, is commonly known as heavy stripping.
Of course, there is 0.03~0.04N/25mm, that is, the stripping force of 3~4 grams, commonly known as gentle stripping.
There is also 1.00N/25mm, which is more than 100 grams of stripping force, commonly known as overweight stripping.
The peel strength of aging and the peeling strength measured after aging are generally slightly larger than that at room temperature.
Residual adhesion is the force of separating paper after the first peeling and the second peeling. The calculated data mainly reflect the curing effect of silicone oil.
The residual adhesion rate of UV curable silicone oil is generally 100%, and the residual adhesion rate of heat curable silicone oil is 90%. A small number of suppliers claim that their residual adhesion rate is 100%. If desilication occurs, the residual adhesion rate of this release paper is generally not higher than 70%.
The test of release paper's technical index is a rather complicated project. General electronic factory and adhesive tape factory can only test several data. As for silicone oil coating, it does not usually appear in the technical report of the supplier.
Selection of release paper
Because the amount of coating directly affects the applicability of glue. Water gel requires a lower amount of silicone oil, while oil and hot melt adhesive require higher silicone oil coating. Because of its high permeability and destructive, it is usually high volume coating.
Coating factories generally choose high-coated release paper, while composite factories generally choose medium-coated release paper. If thermal composite, it also needs to select high-coated release paper. Protective film (hydrogel) only needs low-coated release paper. Medium-coated release paper is suitable for oil-coated protection film and high-coated release paper. Cloth release paper is not suitable for protecting film.
Because of the climate, the die-cutting plant should choose the off-set paper with heavy peeling force in winter and the off-set paper with light peeling force in summer.
Some tapes with special requirements and stripping paper used in die cutting process need to be contacted with the stripping coating supplier. After deep testing and contrast, production activities can be carried out. Otherwise, a lot of waste will be generated.
It is not impossible to use scrambled paper. If the requirement is not high, it can still be used. Otherwise, there will not be so many scrambled suppliers in China.
- Shrink Film Manufacturers Produce Environmental...
- Special Uses Of The Vietnamese Rubber Band
- Strict Packaging Shrinkage Membrane In Shrinkag...
- Making Method Of Fixed Adhesive Tape
- Analysis Of The Development Direction Of PE Shr...
- Development Trend Of Shrinkage Membrane Equipme...
- The Shrinkage Film Plant Describes The Scope Of...
- Shrink Film Manufacturers Packaging Machine Has...
- Talk About The Storage, Transportation And Main...
- What Is The Characteristic Of The Fixed Tape
- Problems To Be Noted In PET Protective Film Pri...
- What Kind Of Protective Film Is Used For Hardwa...
- Why Is Blue Pet Protective Film So Easy To Use?
- PE Protective Film Types And Physical Propertie...
- The Difference Between Water Glue And Oil Glue
- Blue Pet Protective Film, Good Film Is Also Afr...
- Brief Introduction Of Polyethylene For Packagin...
- Where Else Can The PET Film Be Used Besides The...
- Blue PET Silica Gel Protective Film
- Classification And Performance Of Different Rel...