JPH07207237A - Surface-protective film - Google Patents

Abstract

PURPOSE:To obtain a film which can be applied to an adherend near ordinary temp. and ordinary pressure to form a covering having evenness of adhesion and which, after protection, enables the film and the adherend surface to be easily treated, by forming a pressure-sensitive adhesive film layer on a specific base film layer and regulating the resulting structure to have a given elongation. CONSTITUTION:The title film comprises a base film layer comprising a polyolefin resin which is preferably at least one member selected from among ultra-low-density, linear low-density, low-density, and high-density PE's, PP, and poly(butene-1) and a pressure-sensitive film layer preferably comprising at least one member selected from among ethylene/vinyl acetate copolymer resins, ethylene/ethyl acrylate copolymer resins, and ethylene/methyl methacrylate copolymer resins. It has an elongation at 23 deg.C of 200% or higher.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film for temporarily protecting various materials or painted surfaces. More specifically, the present invention relates to a polyolefin-based protective film in which the coating film surface of a completed coating car can be easily covered according to the shape of the completed coating car, and the coating film surface and film can be easily treated even after protection is completed. .

[0002]

2. Description of the Related Art In recent years, in the process of transporting a painted car,
It is often a problem that acid rain fall due to air pollution and damage to the coating film surface due to stones, dust, etc., decrease in gloss, discoloration, etc., and the commercial value of a completely new painted vehicle is significantly reduced. In particular, there was a high probability that the product value would decrease due to long-distance transportation or export to other countries.

For this reason, conventionally, a method of applying wax to a finished vehicle has been adopted, but the thickness is non-uniform and uniform protection cannot be obtained. In addition, solvent scattering during wax application and wax. It had many drawbacks such as the need for wastewater treatment at the time of collection, and required a large number of man-hours and costs.

In order to improve the above-mentioned problems, a method of applying a paint which becomes a peelable coating film after drying and a method of covering a plastic film provided with an adhesive layer have been proposed. However, it is extremely difficult to control the peelability by the method of applying a paint, and when an additive for controlling the peelability is used, the adherend coating film is violated,
In addition, there is a defect that a transfer substance is generated in the adherend coating film.
Moreover, the strength of the coating film was insufficient to withstand the stress applied during peeling, and it took time to dry when a coating film having a certain thickness was obtained in order to increase the strength.

On the other hand, in the method of wrapping the plastic film, there are portions where the film adheres to the adherend coating film and portions where it does not adhere (air-containing parts, wrinkle parts), and the film is peeled off after long-term storage. Then, the film has a defect that a mark is left on a boundary portion between a portion which adheres to a coating film on an adherend and a portion which does not adhere to the film, and a difference in gloss occurs to make the surface of the coating film non-uniform.

The adhesion of the film to the adherend coating film is increased, and the film is heated and softened to improve the appearance after peeling the film, or the adherend is heated to soften the film and applied. There have been proposed methods for bringing the material into close contact with the body, and further methods for bringing the material into close contact with the adherend by utilizing a vacuum. However, the above method causes the film to soften 100%.
Since the attachment work is performed under a heat condition of about ℃, there is a problem that it has a great influence on each part including the interior of the finished car, or that a large-scale vacuum pressurizing facility is required.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems that the prior art has, and it has not been known at all at room temperature and near normal pressure. Thus, it is an object of the present invention to provide a new surface protection film that can be easily attached to various adherend surfaces and can obtain a uniform adhered state.

Another object of the present invention is advantageous in removing unnecessary films for which protection has been completed, pollution that is easily incinerated, waste regulation, and the like, and in addition, an adherend after the protective film is peeled and removed. It is an object of the present invention to provide a surface protective film in which a coating film can be easily treated. Still another object of the present invention is to provide a surface protection film having good weather resistance, which can be used even when a completed vehicle is transported to an exporting country for a long time.

[0009]

The present invention has been made to solve the above problems, and has a base film layer made of at least a polyolefin resin and an adhesive film layer, and has an elongation at 23 ° C. Is 200% or more, and a surface protection film is provided.

Preferably, the polyolefin resin substrate film layer is at least one selected from ultra-low density polyethylene, linear low-density polyethylene, low-density polyethylene, high-density polyethylene, polypropylene and polybutene-1.
A surface protective film that is a film layer composed of seeds,
Preferably a surface protective film containing at least one of the base film layer and the adhesive film layer an ultraviolet absorber and optionally a light stabilizer and / or a colorant,

Preferably, the adhesive film layer is ethylene-
A surface protective film comprising at least one selected from vinyl acetate copolymer resin, ethylene-ethyl acrylate copolymer resin, ethylene-methyl methacrylate copolymer resin, and preferably containing a tackifier in the pressure-sensitive adhesive film layer. And a surface protective film in which a surfactant is contained in the adhesive film layer.

The constituent factors of the present invention will be described in more detail below. The surface protective film of the present invention has a base film layer made of at least a polyolefin resin and an adhesive film layer. As the material of the base film of the surface protection film of the present invention, a low crystalline or highly crystalline resin obtained by polymerizing or copolymerizing mainly an olefin having 2 to 8 carbon atoms is used, and ultra low density polyethylene (hereinafter VLDPE may be abbreviated), low density polyethylene (LDPE), linear low density polyethylene (LLD)
PE), high-density polyethylene (HDPE), polypropylene (PP), atactic polypropylene, polybutene-1 (PB-1), ethylene-acrylic acid copolymer resin, and other resin compositions can be used,

From the viewpoint of the elongation of the film, preferably ultra-low density polyethylene, linear low density polyethylene, low density polyethylene, high density polyethylene, polypropylene,
At least one resin composition selected from polybutene-1 can be used, and VLDPE or LLDP can be used.
A composition mainly containing E is more preferable. Among the above resins, polyethylene resin is ethylene and propylene,
Butene-1, pentene-1, hexene-1, heptene-
Copolymers with 1, 1, octene-1, 4-methylpentene-1, etc. are also included.

Examples of the resin used in the adhesive film layer of the present invention include ethylene-vinyl acetate copolymer resin (E
VA), ethylene-ethyl acrylate copolymer resin (E
EA), ethylene-methyl methacrylate copolymer resin (EMMA), ionomer resin, ethylene-glycidyl methacrylate copolymer resin (EGMA), ethylene-maleic anhydride polymer resin (unsaturated carboxylic acid modified polyolefin), amorphous polyolefin (APO) ) Etc. olefinic copolymer resin, natural rubber, isoprene rubber,
Styrene-butadiene rubber, styrene-butadiene block copolymer resin, styrene-isoprene block copolymer resin,
Rubber resins such as butyl rubber, polyisobutylene, silicone rubber, polyvinyl isobutyl ether, chloroprene rubber, nitrile rubber, glass transition point (Tg) is -10 ° C.
The following acrylic resins and vinyl acetate resins can be used,

Olefin-based copolymer resins are preferable from the viewpoint of obtaining a proper adhesion to the adherend, and ethylene-vinyl acetate copolymer resins, ethylene-ethyl acrylate copolymer resins, and ethylene-methyl methacrylate copolymer resins are particularly preferable. preferable. In the above EVA, the content of the vinyl acetate (VA) component in the resin is preferably 10 to 28% by weight,
In EEA, the content of ethyl acrylate (EA) in the resin is preferably 7 to 20% by weight, and in EMMA, the content of methyl methacrylate (MMA) in the resin is 9 to 2%.
0% by weight is preferred. With such a composition, since the Vicat softening point of the resin is 40 ° C. or higher, it has good characteristics in film formation and winding.

The pressure-sensitive adhesive film layer preferably contains a tackifier from the viewpoint of obtaining an appropriate adhesive force, and further contains a surfactant from the viewpoint of improving wettability and obtaining uniform adhesiveness. preferable. Examples of the tackifier include natural resin tackifiers such as gum rosin, wood rosin, tall oil rosin and other rosins: hydrogenated, disproportionated, polymerized, maleated and methyl, glycerin, pentaerythritol esterified. Rosin derivatives: terpene resins (α-pinene, β-pinene) terpene phenolic resins, aromatic modified terpene resins, terpene resins such as hydrogenated terpene resins, and the like.

Examples of the polymerization synthetic resin-based tackifier include aliphatic synthetic resins containing C5 component (pentane, pentene, methylbutene, etc.) as a polymerization component: C9 component (indene,
Aromatic synthetic resin containing vinyltoluene, Ca alkybenzene, etc.) as a polymerization component: Copolymer resin of the above C5 / C9 component: Petroleum resin obtained by polymerizing alicyclic group such as dicyclopentadiene: Polymerization of dry distillation component of coal Examples of the condensation synthetic resin-based tackifiers include coumarone, indene resins: styrene resins, etc., and alkylphenol resins, xylene resins, etc.

Although one or more of these tackifiers can be used, emulsions of rosin derivatives are used because of their bleeding property on the film surface and ease of removal when the bleeding material is transferred to the adherend coating film. Type is 5 for resin
It is preferable to add less than or equal to wt%.

Surfactants usable in the present invention include:
Nonionic surfactants include, for example, polyoxyalkylene lauryl ether, polyoxyethylene stearyl ether, and other polyoxyalkylene alkyl ethers; for example, polyoxyethylene octylphenol ether, polyoxyethylene nonylphenol ether, and other polyoxyalkylene alkylphenol ethers. For example, sorbitan monolaurate, sorbitan monostearate, sorbitan trioleate and other sorbitan fatty acid esters; for example, polyoxyethylene sorbitan monolaurate and other polyoxyalkylene sorbitan fatty acid esters; for example, polyoxyethylene monolaurate , Polyoxyalkylene fatty acid esters such as polyoxyethylene monostearate;
Glycerin fatty acid esters such as oleic acid monoglyceride and stearic acid monoglyceride; polyoxyethylene / polypropylene / block copolymers; and the like,

Examples of the anionic surfactants include fatty acid salts such as sodium stearate, sodium oleate and sodium laurate; alkyl allyl sulfonates such as sodium dodecylbenzene sulfonate;
Alkyl sulfuric acid ester salts such as sodium lauryl sulfate; for example, sodium monooctyl sulfosuccinate, sodium dioctyl sulfosuccinate, polyoxyethylene lauryl sulfosuccinic acid ester salts such as sodium sulfosuccinate and derivatives thereof; for example, polyoxyethylene lauryl ether sulfate Polyoxyalkylene alkyl ether sulfate ester salts such as soda; for example, polyoxyalkylene alkyl aryl ether sulfate ester salts such as polyoxyethylene nonylphenol ether sulfate sodium;

Examples of the cationic surfactants include alkylamine salts such as laurylamine acetate; quaternary surfactants such as lauryltrimethylammonium chloride and alkylbenzyldimethylammonium chloride.
Examples thereof include secondary ammonium salts; for example, polyoxyethylalkylamine; and examples of the amphoteric surfactants include, for example, alkylbetaine such as laurylbetaine. Further, those in which a part of hydrogen atoms of the alkyl group of these surfactants are replaced with fluorine can also be used. Further, a so-called reactive surfactant having a radical copolymerizable unsaturated bond in the molecular structure of the surfactant can also be used.

Among the above-mentioned surfactants, both the compatibility with the polyolefin resin and the bleeding property to the upper surface of the film are well balanced, the heat resistance during film forming is excellent, and the corrosion of the adherend coating film is caused. From the viewpoint of little influence of, for example, nonionic surfactants are preferable, more preferably polyoxyalkylene fatty acid esters and polyoxyalkylene alkyl ethers, and particularly preferably glycerin fatty acid ester and polyoxyethylene alkyl. It is ether.

The surfactant HLB (Hydrophilic / Lipoph
ilic / Balance) is preferably 5 to 15. Within this range, it is difficult for the surfactant to bleed at the interface between the adherend and the adhesive film layer, and the bleeding surfactant is applied to the adherend when the film is peeled off. Even when it is transferred to the film surface, the bleeding substance can be easily removed by a method such as washing with warm water at 50 ° C. or less.

By further containing a surfactant, the wetting index value of the adhesive film layer in contact with the adherend is 33 dyne / c.
m or more is preferable, the adhesion between the film and the adherend coating film can be made uniform, and the initial adhesiveness is accelerated, and the adherend coating film within a short time after application. Film peeling from is avoided. From the above viewpoint, the addition amount of the surfactant is preferably 0.5 to 5% by weight based on the resin.

In the surface protective film of the present invention, it is preferable that at least one of the base film layer and the pressure-sensitive adhesive film layer contains an ultraviolet absorber and, if necessary, other light stabilizer. The discoloration of the body surface and the film, the decrease in gloss, the change in the film elongation, the change in the film peeling property, etc. are reduced.

The ultraviolet absorber which can be blended with these synthetic resins is appropriately selected from a wide range of types in consideration of the ultraviolet absorbing ability of the ultraviolet absorber and compatibility with the synthetic resin used. You can Examples of usable ultraviolet absorbers include the followings.

Hydroquinone hydroquinone, hydroquinone disalicylate salicylate phenyl salicylate, paraoctyl phenyl salicylate

Benzophenone type 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-methoxy-2'-carboxybenzophenone, 2,4- Hydroxybenzophenone, 2,2'-
Hydroxy-4,4'-dimethoxybenzophenone, 2
-Hydroxy-4-benzoyloxybenzophenone,
2,2'-hydroxy-4-methoxybenzophenone,
2-hydroxy-4-methoxy-5-sulfonebenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,2'-hydroxy-4,4'-dimethoxy-5-sodium sulfobenzo Phenone, 4-dotesiloxy-2-hydroxybenzophenone, 2-hydroxy-5-chlorobenzophenone

Benzotriazole type 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5-carboxylic acid butyl ester benzotriazole, 2- (2'-hydroxy-5'-methylphenyl) -5,6-dichlorobenzotriazole, 2-
(2'-Hydroxy-5'-methylphenyl) -5-ethylsulfone benzotriazole, 2- (2'-hydroxy-5'-tert-butylphenyl) -5-chlorobenzotriazol, 2- ( 2'-hydroxy-5'-tertiary butylphenyl) benzotriazole, 2- (2'-hydroxy-5'-amylphenyl) benzotriazole,
2- (2'-hydroxy-3 ', 5'-dimethylphenyl) benzotriazole, 2- (2'-hydroxy-3)
′, 5′-Dimethylphenyl) -5-methoxybenzotriazole, 2- (2′-methyl-4′-hydroxyphenyl) benzotriazole, 2- (2′-stearyloxy-3 ′, 5'-Dimethylphenyl) -5-methylbenzotriazole

2- (2'-hydroxy-5-carboxylic acid phenyl) benzotriazol ethyl ester, 2-
(2'-hydroxy-3'-methyl-5'-tertiary butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-ditertiary butylphenyl) -5-chloro-benzotriazole, 2- (2'-hydroxy-5 '
-Methoxyphenyl) benzotriazole, 2- (2 '
-Hydroxy-5'-phenylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-
Cyclohexylphenyl) benzotriazole, 2-
(2'-hydroxy-4 ', 5'-dimethylphenyl)
-5-carboxylic acid benzotriazol butyl ester

2- (2'-hydroxy-3 ', 5'-dichlorophenyl) benzotriazole, 2- (2'-hydroxy-4', 5'-dichlorophenyl) benzotriazole, 2- (2 ' -Hydroxy-3 ', 5'-dimethylphenyl) -5-ethylsulfone benzotriazo-
2- (2'-hydroxy-5'-phenylphenyl) benzotriazole, 2- (2'-hydroxy-4)
′ -Octoxyphenyl) benzotriazole, 2-
(2'-hydroxy-5'-methoxyphenyl) -5-
Methylbenzotriazole, 2- (2'-hydroxy-
5'-methylphenyl) -5-carboxylic acid ester benzotriazole, 2- (2'-acetoxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-diter Charly butylphenyl) -5
-Chlorobenzotriazole.

Of these ultraviolet absorbers, those of benzophenone type and benzotriazole type are preferable,
Among them, in benzophenone series, 2,3'-dihydroxy-
4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone and 2,2 ',
4,4'-Tetrahydroxybenzophenone: 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5-methylphenyl) -5,6-in the benzotriazol system Dichlorobenzotriazole, 2- (2-hydroxy-5'-tert-butylphenyl) benzotriazole,

2- (2'-hydroxy-3'-methyl-
5'-tert-butylphenyl) benzotriazole, 2-
(2'-Hydroxy-3 ', 5' ditertiary butylphenyl) -5-chloro-benzotriazole and 2- (2 '
-Hydroxy-5'-phenylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ',
5'-Diter-shartylbutylphenyl) -5-chlorobenzotriazol, 2- (2'-hydroxy-5'-octoxyphenyl) benzotriazole and the like are effective.

The ultraviolet absorber is preferably added in an amount of 0.5 to 5.0% by weight. If the UV absorber is added within this range, the UV cut rate (in the case of 380 nm) is 90% or more, and even if exposed outdoors, it is 1 to 2 years (equivalent to 1,000 hours of sunshine weatherometer) 90% Can hold the above. If the amount is more than this range, whitening of the film, blowing on the surface of the film, and the like tend to be adversely affected.

Other light stabilizers include bis (2,2,2)
6,6, -Tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6, -pentamethyl-4-
Piperidyl) sebacate, 1- [2- [3- (3,5-
Di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy]
A hindered amine light stabilizer such as -2,2,6,6, -tetramethylpiperidine, 4-benzoyloxy-2,2,6,6, -tetramethylpiperidine, a quencher such as organic nickel, or the like can be used.

If desired, a colorant may be added to the surface protective film of the present invention in order to clearly identify the covered portion. Examples of such colorants are titanium oxide, zinc white, lead white, calcium carbonate, gypsum, precipitated silica, carbon black, red iron oxide, aluminum powder, bronze powder, mica, molybdenum red, cadmium yellow, yellow lead, titanium yellow, and oxidized. Inorganic pigments such as chrome green and ultramarine blue: Permanent Red 4R Hansa Yellow 10G, Benzige Yellow GR, Permanent Carmine FB, Phthalocyanine Blue B, Phthalocyanine Green, and other organic pigments.

The surface protective film of the present invention may be formed by any method as long as it can form a base film layer made of at least a polyolefin resin and an adhesive film layer. A method of coating and drying a solution of the composition, a method of molding a substrate film and an adhesive film layer by simultaneous extrusion (multi-layer coextrusion), etc. can be used, but since there is little change in peelability with time, molding by simultaneous extrusion is possible. preferable. .

When the solution of the pressure-sensitive adhesive composition is applied onto the base film, the compounding composition for forming the pressure-sensitive adhesive film layer is prepared in a solvent such as tetrahydrofuran, toluene, xylene, etc., and then the base film is coated and dried. When the base film and the pressure-sensitive adhesive film layer are molded by simultaneous extrusion, the compounding composition of each layer is supplied to an extruder and inflation molding is carried out by a ring die or film molding is carried out by a T-die.

The extrusion temperature is preferably 150 ° C. to 200 ° C., the moldability is good, and there are few troubles such as burning due to heat deterioration of the resin.

As the base film of the surface protective film of the present invention, a film surface-treated by embossing roll, corona discharge, electron beam irradiation or the like can be used. Further, it is possible to provide a printing layer and a release layer on the surface of the base film on which the adhesive film layer is not provided, and a release paper layer on the surface of the adhesive film layer. The surface protective film produced as described above is wound around a paper tube or the like, or supplied in a sheet form with release paper.

The degree of elongation of the surface protective film of the present invention at 23 ° C. is required to be 200% or more, preferably 300% or more so that it can be adhered uniformly to an adherend having a complicated shape. The thickness of the surface protection film is 10
It is preferably μ to 120 μ, more preferably 20 μ to 80 μ, and particularly preferably 30 μ to 60 μ.
Is. When the thickness is within the above range, the film strength and stretchability are good. The thickness of the pressure-sensitive adhesive film layer of the surface protective film is not particularly limited, but 3 µ to 20 µ is suitable.

The adhesive force, that is, the peeling force from the surface of the adherend is preferably 15 to 250 g / 25 mm, more preferably 30 to 100 g / 25 mm. As a result, proper adhesion is maintained and peeling is facilitated.

The surface protective film of the present invention can protect the surface of various materials such as synthetic resins, natural resins, metals, wood products, glass, marble and coated materials during transportation, storage and processing. Examples of the synthetic resin include hydrocarbon resins such as polyethylene and polypropylene: acrylic resins such as polyacrylic acid ester and polymethacrylic acid ester: polyvinyl acetate, vinyl acetate resins such as acetal resin: polyvinyl chloride, polyvinylidene chloride, fluorine Halogen-containing resin such as resin: Diene polymer such as butadiene rubber and chloroprene rubber: Formalin resin such as phenol resin, amino resin and ketone resin: Alkyd resin, terephthal resin, polyester resin such as polycarbonate: Nylon- 6, Polyamide type resin such as nylon-66: Other examples include polyurethane, polyurea, epoxy resin and the like.

Examples of the metal include iron and its alloys, aluminum and its alloys, magnesium and its alloys, copper and its alloys, and metal-plated surfaces. The surface protective film of the present invention can be used for the surface protection of various materials as described above, but is particularly suitable for protecting the surface of an uneven object such as the coating film surface of a finished car.

The method of closely coating the above material with the surface protective film of the present invention is not particularly limited,
For example, a surface protection film on the adherend may be 10
A flexible rubber roller that expands by 20%
Cover by pressing with a sponge roller or brush or by pressing with air or water. In addition, car wash brushes can be used for crimping.

[0046]

EFFECTS OF THE INVENTION According to the surface protective film of the present invention, it is possible to easily carry out the attaching work to various adherends at room temperature and near normal pressure, and to obtain a uniform adhesion state, and to remove and incinerate. It is easy to apply and is advantageous for pollution, waste regulation, etc. In addition, it is easy to treat the adherend coating film after peeling and removed, and the weather resistance can be remarkably improved.

[0047]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but it goes without saying that the present invention is not limited to the examples. The test method used in the present invention is shown below.

(1) Raw materials The raw materials used for preparing the surface protective film are as follows. a. Film molding resin Ultra low density polyethylene (VLDPE): Nanoflex DFDA-1137 (d = 0.905 MI = 1.0) manufactured by Nippon Unicar Co., Ltd.
mp = 119 ° C.) Linear low density polyethylene (LLDPE): NUC polyethylene TUF-2030 (d = 0.919 MI = 1. manufactured by Nippon Unicar Co., Ltd.)
0 mp = 123 ° C.) Polyacrylonitrile / acrylic ester / butadiene copolymer resin (PAN): Mitsui Toatsu Chemical Co., Ltd. Valex E-1010 (d = 1.15 MI = 3)

Ethylene-vinyl acetate copolymer resin (EV
A): Evatate CV2097 manufactured by Sumitomo Chemical Co., Ltd. (VA = 19% d =
0.94 MI = 1.0) Ethylene-vinyl acetate copolymer resin (EVA): Sumitomo Chemical Co., Ltd. EvaTate K2010 (VA = 25% d = 0.
95 MI = 3.0) Ethylene-ethyl acrylate copolymer resin (EEA):
Nippon Unicar Co., Ltd. NVC EEA copolymer 6221 (EA = 10% d = 0.92)
5 MI = 2.6) Ethylene-methyl methacrylate copolymer resin (EMM
A): Sumitomo Chemical Co., Ltd. Acryft CM-2006 (MMA = 15% d = 0.9
3 MI = 3.0) Ethylene-vinyl chloride copolymer resin (EVC): Co., Ltd.
Tohso Ryuron E-1050 (Polymerization degree 1050, Bulk specific gravity 0.48) Ethylene-vinyl alcohol resin (EVOH): Co., Ltd.
Kuraray Eval EP-H-101 (d = 1.17 MI = 1.
6)

B. Ultraviolet absorber (UVA) Tinuvin 326: Ciba Geigy 2 (2'-hydroxy-3'-t-butyl-5'methylphenyl) -5-
Chlorobenzotriazole Tinuvin 327: Ciba Geigy 2 (2'-hydroxy-3'-t-butyl-5'butylphenyl) -5-
Chlorobenzotriazole Tinuvin 328: Ciba Geigy 2 (2'-hydroxy-3'.5'-t-amylphenyl) benzotriazole

C. Light stabilizer (HALS) Sanol LS-622: Sankyo Co., Ltd. dimethyl succinate-1- (2-hydroxyethyl) -4-hydroxy-2.2.6.6 tetramethylpiperidine polycondensate

D. Surfactant diglycerin monooleate (DGMO): Riken vitamin O-71-D (HLB = 5.7) manufactured by Riken Vitamin Co., Ltd. Diglycerin monolaurate (DGML): Rikenal L-71-D manufactured by Riken Vitamin Co., Ltd. (HLB = 7.3) Polyoxyethylene alkyl ether (POEAE):
Riken Vitamin Co., Ltd. Riquemal B-205 (HLB = 12.0) Riquemar B-207 (HLB = 14.0)

E. Tackifier Superester E-702: Arakawa Chemical Industry Co., Ltd. disproportionated rosin ester emulsion type f. Colorant TiO ₂ Type Paque CR-90: manufactured by Ishihara Sangyo Co., Ltd.

(2) Preparation of surface protection film The simultaneous extrusion molding method was carried out as follows. An extruder with a diameter of 55 mmφ L / D = 28 is connected to the resin supply port that forms the outer layer of a three-layer coextrusion die with a diameter of 300 mmφ, and a 65 mm φL port that supplies the resin that forms the intermediate layer.
A three-layer co-extrusion inflation film device was used in which an extruder having a diameter of / D = 28 was connected and an extruder having a diameter of 55 mmφL / D = 28 was connected to a resin supply port for forming an inner layer.

The composition of each layer was previously dispersed with a Henschel mixer, kneaded with a pressure kneader and pelletized with a pentizer, and then the compound pellets forming the adhesive film layer were fed to the resin supply port forming the outer layer. The compound pellets forming the base film layer are supplied to the resin supply port forming the intermediate layer and the resin supply port forming the inner layer, and the temperature of the extruder is 160 ° C for the outer layer, 180 ° C for the intermediate layer, and the die. Molding was carried out at a temperature of 180 ° C. with a blow ratio of 4.8 to obtain a two-layer film consisting essentially of one adhesive layer and one base layer.

(3) Physical properties of film a. Elongation at break (elongation) The elongation at break was measured at 23 ° C under an environment of 55% relative humidity.
It was allowed to stand for a day and then measured, and the obtained value was used as the initial value. Furthermore, the value obtained by measuring the sample after 400 hours elapsed with a sunshine weatherometer under the same conditions as those for measuring the initial value was taken as the value after the accelerated weathering test. Both were measured according to JIS K7127, and the minimum values in the longitudinal direction and the transverse direction are described. b. Wetting index value of the adhesive film layer It was measured according to JIS K6758.

(4) Applied physical properties a. Workability of sticking The following evaluations were made assuming sticking on the curved surface of the finished painted car with a car wash machine. Wrinkle, float and adhere when the film is stretched 10 to 20% (both in the vertical and horizontal directions) to the cubic curved surface of a motorcycle helmet (overcoating with amino alkyd paint) and the surface is lightly rolled with a sponge roll. The condition was observed. Furthermore, after one day, the degree of elimination of wrinkles and floating due to the elastic restoring property and the change in adhesion were observed and evaluated.

B. Peelability (Adhesiveness of adhesive film layer to adherend coating film) Adhesive surface of the film is attached to the white amino alkyd baking paint coating plate (flat plate) made by Nippon Test Panel Co., Ltd. with a sponge roll, at room temperature. After being left for 1 week, the peeling force was measured and used as the initial peeling force. Further, the peeling force after the accelerated weathering test for 400 hours was measured with a sunshine weather ometer. The peeling force was measured by leaving the sample for 1 day in an environment of 23 ° C. and 55% relative humidity, and under the same conditions, 300 mm / mi.
The 180-degree peel strength was measured at a peel speed of n. 15-2
When it is 50 g / 25 mm, the adhesion can be maintained and peeling is easy.

C. Observation of the coated surface after peeling Adhesion by the peeling method B After observing the surface condition of the film such as floating and wrinkles after 400 hours with a sunshine weatherometer, peel off a part of the attached film The presence or absence of transfer substances from the film was checked by observing the surface condition of discoloration and deterioration of gloss of the adherend coating film. Next, if transfer substances from the film are observed on the coating surface,
Pressure of 10kg / cm ² , 30cm assuming washing of car wash machine
It was washed with water (room temperature water) for 20 seconds from right above (angle of 90 °) at a distance, and the removability of the transferred matter was observed.

Items that cannot be quantified by the respective evaluation criteria were evaluated according to the following criteria. ◎ Very good or no change is observed. ○ Good or slightly changed. △ Slightly defective or changed. × Defects or changes are largely observed.

Example 1 Pelletized VLDPE [Nanoflex DFDA-1137 d = 0.905, MI = 1.0 mp =, manufactured by Nippon Unicar Co., Ltd.]
119 ° C.] is pulverized with a pulverizer (rotoplex),
Charge 100 parts by weight into a Henschel mixer, and further add 2.0 parts by weight of UV absorber Tinuvin 326 (manufactured by Ciba-Geigy), light stabilizer (HALS), Sanol LS-622.
[Sankyo Co., Ltd.] 0.5 part by weight, colorant / TiO ₂ CR
90 [manufactured by Ishihara Sangyo Co., Ltd.] (3.0 parts by weight) are sequentially charged, and the temperature is raised to 60 ° C. to mix and disperse. The obtained composition is kneaded by a pressure kneader at 180 ° C. and pelletized by a pelletizer to obtain a resin composition for forming a base film layer.

Similarly, pelletized EVA [Evatate CV-2097 VA = 19% manufactured by Sumitomo Chemical Co., Ltd. d = 0.
94 MI = 1.0] was crushed, and 100 parts by weight of the mixture was charged into a Henschel mixer, and the surfactant DGMO Riquemar O-7 was added.
1-D [manufactured by Riken Vitamin Co., Ltd.] 1.0 part by weight, tackifier Superester E-702 [Arakawa Chemical Industry Co., Ltd.]
Preparation] 2.0 parts by weight and 100 parts by weight of powdered EVA were charged, and then mixed, dispersed and kneaded under the same conditions (however, 160
C.) and pelletized to form a pressure-sensitive adhesive film layer.

The resin composition thus obtained was used in the above-mentioned three-layer coextrusion film die and 40 μ of a base film layer of 35 μ and an adhesive film layer of 5 μ under the above film forming conditions.
A two-layer strippable film was made. Table 4 shows film physical properties and applied physical properties of the obtained surface protection film. The above-mentioned film showed good workability for sticking, and when it was stuck on the cubic curved surface of a motorcycle helmet, no wrinkle or floating was observed and the adhesion was good. Further, it was shown to have good releasability even after being adhered to an amino alkyd baking paint coated plate and subjected to a 400-hour accelerated weathering test with a sunshine weather o-meter, and discoloration of the adherend coating film after peeling and deterioration of gloss were not observed.

Examples 2 to 12 Surface protective films were prepared in the same manner as in Example 1 except for the film composition and the thickness of each film layer shown in Tables 1 and 2. All showed good workability and peelability, and there was little change in the appearance of the adherend coating film.

Example 13 EVA [Sumitomo Chemical Co., Ltd. Evatate-2097 VA = 19% d = 0.94] in an SUS autoclave
MI = 1.0] 100 parts by weight, DGMO (Rikemal O-71-D manufactured by Riken Vitamin Co., Ltd.) 1.0 part by weight, tackifier-Super Ester E-702 (manufactured by Arakawa Chemical Industries Co., Ltd.) 2.0 Parts by weight and tetrahydrofuran 200
After charging parts by weight, the temperature was raised and heated at 70 ° C. for 1 hour to dissolve under pressure.

The contents were cooled and the resulting solution was used in Example 1.
100 parts by weight of VLDPE, 1.0 parts by weight of TINUVIN 326, HALS / Sanol LS molded by the method shown in FIG.
A roll gap was prepared by a roll coater so as to have a thickness of 5 μm and coated on a 35 μm thick base film consisting of −622 0.5 parts by weight and a coloring agent TiO ₂ 3.0 parts by weight. After application of the solution, the solution was passed through a drying zone at 40 to 70 ° C. for 1.5 minutes to obtain a film of the solution application drying method.

Example 14 A surface protective film was prepared in the same manner as in Example 13 except for the film composition and the thickness of each film layer shown in Table 2. Comparative Examples 1 to 3 A surface protective film was prepared in the same manner as in Example 1 except for the film composition shown in Table 3. Each of the obtained films had poor workability in sticking and could not obtain uniform adhesion to the adherend. Furthermore, after being attached to an amino alkyd baking paint coated plate and subjected to a 400-hour accelerated weathering test with a sunshine weatherometer, peeling was impossible in Comparative Example 1 due to deterioration of the base film layer and the adhesive film layer, and the film was broken. However, in Comparative Examples 2 and 3, a strong force was required for peeling.

[0068]

[Table 1]

[0069]

[Table 2]

[0070]

[Table 3]

[0071]

[Table 4]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B32B 27/18 Z 8413-4F

Claims (10)

[Claims] 1. A base film layer comprising at least a polyolefin resin and an adhesive film layer, and at 23 ° C.
A surface protection film having an elongation of 200% or more. 2. The polyolefin resin base film layer is a film layer comprising at least one selected from ultra low density polyethylene, linear low density polyethylene, low density polyethylene, high density polyethylene, polypropylene and polybutene-1. The surface protective film according to claim 1. 3. The ultraviolet absorber and, if necessary, other light stabilizer and / or colorant are contained in at least one of the base film layer and the adhesive film layer. Surface protection film. 4. The adhesive film layer comprises at least one selected from an ethylene-vinyl acetate copolymer resin, an ethylene-ethyl acrylate copolymer resin, and an ethylene-methyl methacrylate copolymer resin. The surface protection film described. 5. The surface protective film according to claim 1, wherein the pressure-sensitive adhesive film layer contains a tackifier. 6. The surface protective film according to claim 1, wherein the pressure-sensitive adhesive film layer contains a surfactant. 7. The surface protective film according to claim 6, wherein the surfactant has an HLB of 5 to 15. 8. The surface protection film according to claim 6, wherein the pressure-sensitive adhesive film layer containing the surfactant has a wetting index value of 33 or more. 9. The surface protective film according to claim 1, wherein a release agent layer is provided on the surface of the base film layer on which the adhesive film layer is not provided. 10. The surface protective film according to claim 1, wherein the surface protective film is produced by a simultaneous extrusion molding method.