KR101988074B1 - Adhesive film for automobile - Google Patents

Abstract

The present invention is an acrylic foam layer; A rubber adhesive layer formed on one or both surfaces of the acrylic foam layer; And a primer layer between the acrylic foam layer and the rubber adhesive layer. It includes, and the primer layer relates to an adhesive film for automobiles comprising a Cl-containing composition.

Description

Adhesive film for automobiles {ADHESIVE FILM FOR AUTOMOBILE}

The present invention relates to an adhesive film for automobiles.

Background Art Conventionally, pressure-sensitive adhesive tapes or sheets are used for joining members in various fields such as applications requiring adhesive force and shear strength at room temperature, for example, automobiles, mechanical parts, electronic products, building materials, and the like. Such a pressure-sensitive adhesive member is produced by, for example, curing the adhesive agent composition containing (meth) acrylic acid alkyl ester as a monomer main component with ultraviolet rays.

Recently, a pressure-sensitive adhesive tape having a core layer containing a rubber-based pressure-sensitive adhesive is commercially available, and the adhesive tape for automobiles not only withstands exposure environments such as UV and rain water for a long time, but also external physical shocks or vibrations. Acrylic foam tapes have been applied because they have to withstand.

In this regard, although a rubber-based adhesive and an acrylic foam tape including the same have been studied, a rubber-based adhesive has excellent durability and reliability in harsh environments, but has a problem in that adhesive strength with acrylic foam is inferior.

In order to solve the above problems, the present invention includes a primer layer formed of a composition containing Cl, thereby increasing the adhesive force between the acrylic foam layer and the rubber-based adhesive layer to provide an automotive adhesive film having excellent adhesion and durability.

In order to solve the above problems,

The present invention in one embodiment, the acrylic foam layer; A rubber adhesive layer formed on one or both surfaces of the acrylic foam layer; And a primer layer between the acrylic foam layer and the rubber adhesive layer. It includes, and the primer layer provides a vehicle adhesive film comprising a Cl-containing composition.

The Cl-containing composition may provide a vehicle adhesive film including a chlorinated polyolefin (CPO) resin and a binder resin.

The degree of chloride of the chlorinated polyolefin resin may provide an adhesive film for automobiles of 0.0001 mass% to 0.001 mass%.

The binder resin may provide an adhesive film for automobiles which is at least one selected from the group consisting of polyurethane, polyamide, polyester, polyether, polycarbonate, and combinations thereof.

The Cl-containing composition may provide an automotive adhesive film including at least one solvent selected from the group consisting of methyl propyl ketone, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, and combinations thereof.

With respect to 100 parts by weight of the Cl-containing composition, it is possible to provide a vehicle adhesive film comprising 5 to 20 parts by weight of the polychlorinated chloride resin, 1 to 5 parts by weight of the binder resin.

Solid content of the Cl-containing composition can provide an automotive adhesive film of 10 to 25% by weight.

The rubber adhesive layer may provide an adhesive film for automobiles including at least one selected from the group consisting of isoprene rubber, styrene rubber, polybutadiene rubber, acrylonitrile butadiene rubber, butyl rubber, polychloroprene rubber, urethane rubber, and acrylic rubber. Can be.

The styrene rubber includes styrene-isoprene-styrene block copolymer, styrene-butadiene-styrene block copolymer, styrene-butylene-styrene block copolymer, styrene-propylene-styrene block copolymer, acrylonitrile-butylene-styrene It is possible to provide an adhesive film for automobiles which is at least one selected from the group consisting of copolymers and carboxylic acid derivatives thereof.

The rubber-based adhesive layer may provide a vehicle adhesive film further comprising a tackifier and a plasticizer.

The styrene rubber may provide an adhesive film for automobiles having a styrene content of 15 to 20% by weight.

The acrylic foam layer may provide an adhesive film for automobiles including a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms and acrylic acid.

The (meth) acrylic acid ester monomer may provide a vehicle adhesive film of 85 to 95% by weight and the acrylic acid is 5 to 15% by weight.

The acrylic foam layer includes 0.01 to 1 part by weight of photoinitiator and 0.1 to 2 parts by weight of crosslinking agent based on 100 parts by weight of the composition containing acrylic acid and a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms. An adhesive film can be provided.

The primer layer may have a thickness of 4 μm to 6 μm.

Since the adhesive film for automobiles of the present invention includes a Cl-containing primer layer, it maintains excellent adhesion between the acrylic foam and the rubber-based adhesive layer, and is excellent in external impact and absorption, and has excellent adhesive performance even on a substrate having low surface energy. .

1 is a schematic cross-sectional view of an adhesive film for a vehicle according to an embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving the same will be apparent with reference to the following embodiments. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms. The present embodiments are merely provided to make the disclosure of the present invention complete, and to fully convey the scope of the invention to those skilled in the art, and the present invention is defined by the scope of the claims. It will be. Like reference numerals refer to like elements throughout.

The present inventors, while studying the automotive adhesive film, by introducing a primer layer containing a Cl-containing composition between the rubber adhesive layer and the acrylic foam, while maintaining a constant durability, while maintaining excellent adhesion between the rubber adhesive layer and the acrylic foam It confirmed and completed this invention.

The present invention is an acrylic foam layer; And a rubber adhesive layer formed on one or both surfaces of the acrylic foam layer, and provides a vehicle adhesive film including a primer layer comprising a Cl-containing composition between the acrylic foam layer and the rubber adhesive layer.

Automotive Adhesive Film

Primer layer

The present invention provides the primer layer to improve the adhesion between the rubber-based adhesive layer and the acrylic foam layer, as a result to implement an automotive adhesive film having excellent adhesion.

The primer layer may include a Cl-containing composition, specifically, after applying the composition may be dried to form a primer layer.

In addition, the Cl-containing composition may include a chlorinated polyolefin (CPO) resin and a binder resin.

The chlorinated polyolefin resin may include Cl in the primer layer, and ionic bonding between Cl of the primer layer and hydrogen of the acrylic foam layer may be performed.

 In addition, the physical bonding between the rubber-based adhesive layer and the primer layer is achieved when each layer is subjected to heat aging after plywood, thereby improving the adhesive performance between the rubber-based adhesive layer and the acrylic foam layer.

Existing rubber adhesive layer has excellent durability and reliability in the harsh external environment than the acrylic adhesive layer having excellent adhesive strength with the acrylic foam layer, while the adhesive strength with the acrylic foam had a problem.

Thus, the present invention includes a primer layer comprising the Cl-containing composition between the acrylic foam layer and the rubber-based adhesive layer, it is possible to solve the above problems and implement an automotive adhesive film having excellent adhesion and durability.

The chlorinated polyolefin resin is a part of hydrogen in the polymer, such as ethylene chloride or propylene chloride. At this time, the weight of chlorine to the total weight of the chlorinated polyolefin resin is referred to as the degree of chloride.

The chloride level of the chlorinated polyolefin resin may be about 0.0001 mass% to about 0.001 mass%, and specifically, the chloride level may be about 0.0001 mass% to about 0.0005 mass%.

If the chloride level is less than 0.0001 mass%, there is a fear that the adhesion ability of attaching two phases as a primer to the interface between acrylic and rubber phases may be deteriorated. If the chloride content is more than 0.001 mass%, excess halogen is detected to produce a product that is not environmentally friendly. There is.

Therefore, by including the chloride polyolefin resin having the chloride degree within the above range, it is possible to implement the primer layer containing an appropriate amount of Cl to improve the adhesion performance of the film.

In addition, the Cl may be included in an amount of 0.001 mg to 0.01 mg, specifically 0.003 mg to 0.005 mg so as not to exceed the environmental hazardous substance threshold.

The chlorinated polyolefin resin may be used alone or in combination of several kinds of resins having different degrees of chloride.

The binder resin may be at least one selected from the group consisting of polyurethane resins, polyamide resins, polyester resins, polyether resins, polycarbonate resins, and combinations thereof.

In particular, the polyamide resin is most preferred because it can be easily mixed with other components, has excellent mechanical strength, heat resistance, abrasion resistance, flexibility, low temperature properties, and can exhibit high adhesive strength.

The composition may include a variety of solvents, and by way of non-limiting example, may be at least one selected from the group consisting of methyl propyl ketone, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, and combinations thereof, and is preferred. Preferably toluene, xylene.

For about 100 parts by weight of the Cl-containing composition, the chloride polyolefin resin may include about 5 to about 20 parts by weight, and the binder resin may include about 1 to about 5 parts by weight.

When the amount of the chlorinated polyolefin resin is less than about 5 parts by weight, there is a problem in that the adhesive strength improvement effect is insignificant, and when included in excess of about 20 parts by weight, solubility in the composition may be reduced.

Therefore, in order to reinforce the adhesiveness and impact properties of the primer layer is most preferably included in the above range.

In addition, when the binder resin is included in less than about 1 part by weight, the viscosity of the composition may be lowered and the adhesion may be reduced. When the binder resin is included in an amount of more than about 5 parts by weight, the cohesive force of the composition may be lowered, so that There is a problem that the compatibility is lowered.

Solids of the Cl-containing composition may be 10 to 25% by weight. By adjusting the content of the solid content in the above range can be properly maintained the adhesion, durability and mechanical strength of the primer layer.

Acrylic foam floor

The acrylic foam layer comprises an acrylic resin. Although the acrylic resin which can be used by this invention is not specifically limited, It can contain the (meth) acrylic acid ester monomer and acrylic acid which have a C1-C12 alkyl group.

At this time, when the alkali contained in the monomer is too long, the cohesive force may be lowered and the glass transition temperature (Tg) and the adhesiveness may become difficult to be controlled. Therefore, the (meth) acrylic acid ester having an alkyl group having 1 to 12 carbon atoms It is preferable to use a system monomer.

The weight ratio of the (meth) acrylic acid ester monomer and the acrylic acid is selected from a range capable of achieving the desired effect and is not particularly limited, but the (meth) acrylic acid ester monomer is about 85 to about 95% by weight and the Acrylic acid is preferably used at about 5 to about 15% by weight.

When the acrylic acid is less than about 5% by weight, the cohesive force is lowered, and when the acrylic acid is more than about 15% by weight, the adhesive force is lowered.

The type of the (meth) acrylic acid ester monomer is not particularly limited. Examples of such monomers include alkyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, and n-propyl (meth). Acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, sec-butyl (meth) acrylate, pentyl (meth) acrylate, 2-ethylhexyl ( Meth) acrylate, 2-ethylbutyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, lauryl (meth) acrylate and tetradecyl (Meth) acrylate can be mentioned, In this invention, 1 type, or 2 or more types of these can be used.

In addition, acrylic acid copolymerizable with the (meth) acrylic acid ester monomer may be a polar monomer. Although the said acrylic acid is not specifically limited, either, A carboxyl group-containing monomer and / or a nitrogen-containing monomer are especially preferable.

 Examples of the carboxyl group-containing monomer may include at least one selected from the group consisting of (meth) acrylic acid, maleic acid and fumaric acid, and examples of the nitrogen-containing monomer may include acrylamide, N-vinylpyrrolidone and N-vinyl caprolactam. One or more selected from the group consisting of.

The acrylic foam layer of the present invention may further include a photoinitiator and a crosslinking agent in a composition containing a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms and acrylic acid.

The photoinitiator may react by irradiation with ultraviolet rays in the process of forming the acrylic foam layer to initiate a curing reaction of the composition. As the photoinitiator in the above may be used that is commonly used in this field, which is not particularly limited.

Examples of the photoinitiator include benzoin methyl ether, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, α, α-methoxy-α-hydro From the group consisting of roxyacetophenone, 2-benzoyl-2- (dimethylamino) -1- [4- (4-morphonyl) phenyl] -1-butanone and 2,2-dimethoxy-2-phenylacetophenone One or more selected.

The photoinitiator is preferably added in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the composition. When less than 0.01 part by weight of the photoinitiator is added, not only the crosslinking may be sufficiently achieved, but an improvement effect of cohesion may not be obtained. When the amount is added in excess of 1 part by weight, initial tack and adhesion are significantly reduced. There is a concern.

The crosslinking agent may adjust the adhesive physical properties in view of improving cohesion. Although the kind of crosslinking agent which can be used by this invention is not specifically limited, It is preferable that it is a component which can participate in reaction by irradiation, such as an ultraviolet-ray.

Examples of the crosslinking agent include polyfunctional such as 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, 1,2-ethylene glycol diacrylate and 1,12-dodecanediol acrylate. Acrylate crosslinking agents; Polyfunctional isocyanate crosslinking agents; And it may include one or more selected from the group consisting of a polyfunctional epoxy-based crosslinking agent, but is not limited thereto. The crosslinking agent is preferably added in about 0.1 to about 2 parts by weight based on 100 parts by weight of the composition. If less than about 0.1 part by weight of the crosslinking agent is added, there is a fear that the adhesive force may be lowered, and if more than about 2 parts by weight is added, the cohesion may be reduced.

Other additives that may be added in addition to the photoinitiator and the crosslinking agent include a porous filler, a coupling agent, an antistatic agent, a surfactant, a tackifier and a processing oil, and the like, and such additives are conventionally used in the art. It can be suitably added in the range which does not impair the purpose of the.

Rubber system  Adhesive layer

The rubber adhesive layer may include at least one selected from the group consisting of isoprene rubber, styrene rubber, polybutadiene rubber, acrylonitrile butadiene rubber, butyl rubber, polychloroprene rubber, urethane rubber, and acrylic rubber.

Since the rubber forms a double bond ring, it is preferable to use styrene rubber having high hardness. The styrene rubber may be a styrene-isoprene-styrene block copolymer, a styrene-butadiene-styrene block copolymer, a styrene-butylene- At least one selected from the group consisting of styrene block copolymers, styrene-propylene-styrene block copolymers, acrylonitrile-butylene-styrene copolymers, and carboxylic acid derivatives thereof.

In particular, the styrene rubber may be a styrene-isoprene-styrene (SIS) block polymer. The SIS block copolymer is a kind of rubber adhesive and belongs to an A-B-A type polymer, and is a styrene-based thermoplastic elastomer having a molecular structure model in which A of the end block is made of polystyrene and B of the rubber intermediate block is made of polyisoprene.

Although the SIS block copolymer used for this invention is not specifically limited, Usually, the solution viscosity (MPa * s [cps], 25 degreeC) should just be about 1000-3000, and with respect to the whole composition of a rubber-based adhesive layer, It is preferable that content of the said SIS block copolymer is 10-30 weight%. If the content of the SIS block copolymer is less than 10% by weight, the cohesive force is insufficient, whereas if the content of the SIS block copolymer is more than 30% by weight, the adhesion is insufficient, which is not preferable.

In addition, the styrene rubber may have a styrene content of about 15 to about 20% by weight. As the styrene is a hard segment, the content of styrene may affect the physical properties of the entire rubber, and as the amount of styrene increases, the rubber may increase thermoplasticity.

 If the styrene content of the present invention is less than 15% by weight, there is a fear that the cohesive force is insufficient, if more than 20% by weight, the hardness is high, there is a problem that the adhesive strength falls. It is preferable that it is 15% or more from the durability viewpoint of an adhesive, It is preferable when the styrene content is 16-18 weight%.

In addition, the rubber adhesive layer may further include a tackifier and a plasticizer.

Although the said tackifier is not specifically limited, For example, substituted saturated hydrocarbon resin (synthetic petroleum resin), rosin ester derivative, terpene resin, phenol resin etc. are preferable.

In addition, a substituted saturated hydrocarbon resin is not specifically limited, What is necessary is just to contain 1 type (s) or 2 or more types in the above in this invention.

The content of the tackifier is not particularly limited, but is preferably about 10 to about 150 parts by weight based on 100 parts by weight of the rubber contained in the rubber-based adhesive layer. When content of a tackifier is less than 10 weight part, adhesive force becomes inadequate, and when content of a tackifier exceeds 150 weight part, adhesive force becomes it strong too much and can provide a foreign material to a base material when peeling.

Although the said plasticizer is not specifically limited, For example, higher alcohols, such as liquid paraffin, hardened oil, hardened castor oil, and octyl dodecanol, squalane, squalene, castor oil, a liquid rubber (polybutene), isopropyl acid myrist acid Fatty acid ester, such as these, etc. are mentioned. In the present invention, any one or two or more of these may be contained.

The content of the plasticizer is preferably about 1 to about 10 parts by weight based on 100 parts by weight of the rubber contained in the rubber-based adhesive layer. If the content of the plasticizer is less than 1 part by weight, the adhesive layer is excessively cured, so that the adhesive force is insufficient. On the other hand, when content of a plasticizer exceeds 10 weight part, an adhesive layer will soften too much, and stickiness will arise or remain easily.

1 is a schematic cross-sectional view of an automotive adhesive film 100 according to an embodiment of the present invention. Most preferably, the acrylic foam layer 10 is about 1000 μm, and the primer layer 30 is about 5 μm. The adhesive layer 20 is about 50 mu m.

The thickness of the primer layer of the adhesive film for automobiles of the present invention may be about 4 ㎛ to about 6 ㎛.

The thickness below the above range has no effect of adding the primer layer, and the excess thickness may cause the primer layer to be somewhat thick, resulting in a phenomenon of being pushed during film adhesion or rather deterioration in adhesion.

Therefore, when the primer layer is formed at the thickness, excellent adhesion between the rubber adhesive layer and the acrylic foam layer can be realized.

In addition, the rubber-based adhesive layer of the automotive adhesive film may further include a base layer.

The base layer may use various plastic films, paper, non-woven fabric, glass or metal, and specifically, an ester-based polymer film including polyethylene terephthalate, a styrene-based polymer film including polystyrene, and an olefin including cyclic olefin polymer. Polymer film, carbonate polymer film containing polycarbonate, imide polymer film containing polyimide, sulfone polymer film containing polyether sulfone, cellulose polymer film containing triacetyl cellulose, or poly An acrylic polymer film including methyl methacrylate may be used, but not limited to a specific polymer, but any polymer film used as a base film of a protective film or an adhesive film is applicable.

The following presents specific embodiments of the present invention. However, the embodiments described below are merely for illustrating or explaining the present invention in detail, and thus the present invention is not limited thereto.

< Example  And Comparative example >

<Example 1>

Acrylic foam floor fabrication

90 parts of 2-ethyl hexyl acrylate and 10 parts of polar monomer acrylic acid were thermally polymerized in a 1 liter glass reactor to obtain a viscosity 3500 cP syrup. 0.5 part by weight of Igacure-651 (a, a-methoxy-a-hydroxyacetophenone) as a photoinitiator and 0.35 part by weight of 1,6-hexanediol diacrylate (HDDA) as a crosslinking agent based on 100 parts by weight of the obtained syrup. After stirring sufficiently. 5 parts of glass bubbles and 2 parts of silica were mixed here, and it stirred until it became uniform enough. The mixture was degassed under reduced pressure using a vacuum pump, and then a 1.0 mm thick acrylic foam layer was prepared using a micro bar.

Rubber system Adhesive layer  Produce

The SIS-based linear block copolymer is mixed with a toluene solvent to prepare a composition. After adding 150 parts of a tackifier to increase the adhesive properties to the composition with respect to 100 parts by weight of the SIS-based linear block copolymer and stirred for one hour, after degassing at room temperature to coat the silicone release PET, 80 ° C. 1 minute in the oven, dried for 2 minutes at 110 ° C oven and UV-cured to prepare a rubber-based adhesive layer of 50㎛ thickness.

primer  Composition preparation

To 100 parts by weight of the total composition, 15 parts by weight of a polyolefin having a chloride degree of 0.0005% by mass and 5 parts by weight of a polyamide resin were added, followed by stirring at 70 ° C for 5 hours in a toluene solvent to prepare a Cl-containing composition having a solid content of 10%. It was.

Acrylic foam tape manufacturer

The primer composition was applied to a thickness of 5 μm between the rubber adhesive layer and the acrylic foam layer, and laminated with a 5 kg roll, followed by drying, to prepare an adhesive film.

Comparative Example 1

An adhesive film was prepared in the same manner as in Example 1, except that silica primer was used instead of polyolefin chloride when preparing the primer composition.

Comparative Example 2

An adhesive film was prepared in the same manner as in Example 1 except that the primer layer was not applied.

< Experimental Example >

1. Initial Adhesion Evaluation

Test was carried out 20 minutes after the attachment according to the test method of KS A1107.

2. Interface adhesion creep

The adhesive film was prepared as a specimen of 1 × 1 inch (width X length) and attached to a sus (SUS), and the average value was recorded by measuring the time when the adhesive film fell by hanging 1 kg weight at a high temperature of 80 ° C. five times.

3. Dimensional stability evaluation

After immersing the specimen in the water bath, the shrinkage rate for the difference in length measured after leaving in an oven at 80 ° C was evaluated as less than 2.0% for good, 2.0 to 2.2% for moderate, and more than 2.2% for bad.

The initial adhesion, interfacial adhesion and dimensional stability evaluation results for Example 1 and Comparative Examples 1 and 2 are shown in Table 1 below.

Example 1 Comparative Example 1 Comparative Example 2 Initial adhesion
(kg / in) 6 5 2 80 ℃ Creep
Interface adhesion
(Min) 10000 2000 30 Dimensional stability good usually Bad

As shown in Table 1, when the primer layer made of Cl-containing composition is applied between the acrylic foam layer and the rubber-based adhesive layer it can be seen that the initial adhesion, interfacial adhesion and dimensional stability is excellent.

100: automotive adhesive film
10: acrylic foam layer
20: rubber adhesive layer
30: primer layer

Claims (13)

Acrylic foam layer;
A rubber adhesive layer formed on one or both surfaces of the acrylic foam layer; And
A primer layer between the acrylic foam layer and the rubber adhesive layer; Including,
The primer layer comprises a Cl containing composition,
To 100 parts by weight of the Cl-containing composition, 5 to 20 parts by weight of a polyolefin chloride and 1 to 5 parts by weight of a binder resin, the chloride degree of the polyolefin chloride is 0.0001 mass% to 0.0005 mass%
Automotive adhesive film.
delete delete The method of claim 1,
The binder resin is at least one selected from the group consisting of polyurethane, polyamide, polyester, polyether, polycarbonate, and combinations thereof
Automotive adhesive film.
delete The method of claim 1,
The rubber adhesive layer includes at least one selected from the group consisting of isoprene rubber, styrene rubber, polybutadiene rubber, acrylonitrile butadiene rubber, butyl rubber, polychloroprene rubber, urethane rubber, and acrylic rubber
Automotive adhesive film.
The method of claim 6,
The styrene rubber includes styrene-isoprene-styrene block copolymer, styrene-butadiene-styrene block copolymer, styrene-butylene-styrene block copolymer, styrene-propylene-styrene block copolymer, acrylonitrile-butylene-styrene At least one selected from the group consisting of copolymers and carboxylic acid derivatives thereof
Automotive adhesive film.
The method of claim 6,
The rubber adhesive layer further comprises a tackifier and a plasticizer
Automotive adhesive film.
The method of claim 6,
The styrene rubber has a styrene content of 15 to 20% by weight
Automotive adhesive film.
The method of claim 1,
The acrylic foam layer comprises a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms and acrylic acid
Automotive adhesive film.
The method of claim 10,
The (meth) acrylic acid ester monomer is 85 to 95% by weight and the acrylic acid is 5 to 15% by weight
Automotive adhesive film.
The method of claim 1,
The acrylic foam layer contains 0.01 to 1 part by weight of a photoinitiator and 0.1 to 2 parts by weight of a crosslinking agent based on 100 parts by weight of the composition containing acrylic acid and a (meth) acrylic acid ester monomer having an alkyl group having 1 to 12 carbon atoms.
Automotive adhesive film.
The method of claim 1,
The thickness of the primer layer is 4 ㎛ to 6 ㎛
Automotive adhesive film.

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