WO2013005368A1

WO2013005368A1 - Protection film for wheel

Info

Publication number: WO2013005368A1
Application number: PCT/JP2012/003367
Authority: WO
Inventors: 甲斐　誠; 和彦金原; 加藤　直人; 一康花木
Original assignee: 日東電工株式会社
Priority date: 2011-07-05
Filing date: 2012-05-23
Publication date: 2013-01-10
Also published as: JP2013014710A

Abstract

A protection film (10) for wheels has a base material layer, and an adhesive layer that is provided on one surface of the base material layer. The protection film for wheels has one or more cut portions (18) at an outer end portion. Each of the cut portions (18) may have a rounded leading edge portion (18a) close to the center. The protection film for wheels may be formed in a circular shape. A plurality of cut portions may be disposed at equal intervals.

Description

Protective film for wheel

The present invention relates to a wheel protective film.

Conventionally, when an automobile wheel such as an aluminum wheel is transported by a ship, for example, when transported by ship, water infiltrates from the outside into the inside of the automobile wheel due to a change in humidity inside the ship. There is a problem that rust is generated on the disc brake, and a protective film is attached to the wheel surface in order to prevent the rust.

The protective film used for automobile wheels must be kept in the state of being attached until the car is delivered. When the protective film is peeled off after delivery, it can be easily peeled off. In addition, it is required that no adhesive residue is generated on the wheel surface.

In Patent Document 1, a protective film is attached to the outside of a disk surface of an automobile wheel, a pressure relief portion is formed on the protective film, and the wheel is caused by a pressure difference or negative pressure inside and outside the automobile wheel during transportation of the automobile. A method for preventing the protective film affixed to the outer surface from peeling off is disclosed.

Patent Documents 2 to 9 disclose automobile brake disc antitrust films and the like that have weather resistance and are difficult to peel off from the wheel surface.

JP 2005-155758 A JP 2006-35914 A International Publication No. 05/090453 Pamphlet International Publication No. 05/090098 Pamphlet International Publication No. 07/114450 Pamphlet WO08 / 111663 pamphlet Japanese Patent No. 3879985 JP 2008-137547 A JP 2009-227746 A

By the way, when the protective film as described above is attached to the wheel, if the attaching surface of the wheel is uneven or the attaching surface itself is a curved surface, wrinkles are likely to occur at the outer edge of the protective film. When the vehicle travels in a state where such wrinkles are generated, there is a possibility that peeling will start from the wrinkles due to wind pressure.

However, the protective films disclosed in the above-mentioned patent documents do not consider this point, and there is room for further improvement.

This invention is made | formed in view of such a condition, The place made into the objective is providing the protective film for wheels which can maintain the stable sticking state of the protective film to wheels, such as a vehicle. It is in.

In order to solve the above problems, the wheel protective film according to an aspect of the present invention includes a base material layer and a pressure-sensitive adhesive layer provided on one surface of the base material layer. The wheel protective film has one or more cut portions formed inward from the outer edge.

According to this aspect, when the protective film is attached to the wheel, the generation of wrinkles due to the shape of the wheel can be suppressed.

A tear preventing portion connected to the cut portion may be formed at the inner end of the cut portion. The tear preventing portion may be an opening section defined by a curve. The wheel protective film may be circular, and a plurality of cut portions may be arranged at equal intervals.

Another aspect of the present invention is also a wheel protective film. This protective film for wheels has a base material layer and an adhesive layer provided on one surface of the base material layer. The wheel protective film has one or more notches formed at the outer edge.

The notch may have an R shape at the tip close to the center. The wheel protective film may be circular, and a plurality of notches may be arranged at equal intervals.

In the protective film for a wheel, a ventilation part through which air can pass from one surface to the other surface may be formed. The ventilation part may be a slit. The slit may be formed in an arc shape.

According to the present invention, it is possible to maintain a stable application state of the protective film to a wheel of a vehicle or the like.

It is a front view of the protective film which concerns on 1st Embodiment. FIG. 2 is an AA cross-sectional view of the protective film shown in FIG. It is a front view of the protective film which concerns on 2nd Embodiment. It is a front view of the protective film which concerns on 3rd Embodiment. It is a front view of the protective film which concerns on 4th Embodiment. It is a front view of the protective film which concerns on 5th Embodiment. It is a front view of the protective film which concerns on 6th Embodiment.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the following embodiments, an automobile wheel will be described as an example of an application target of the protective film, but the application target of the protective film is not limited to such a wheel. The wheel protective film according to each embodiment described below (hereinafter, appropriately referred to as “protective film”) includes a base material layer and a pressure-sensitive adhesive layer provided on one surface of the base material layer.

In addition, the protective film according to each embodiment has scratches on the wheel surface during the period until delivery, dirt adheres to it, and further, when the vehicle is transported on the sea for a long time, such as when exporting automobiles, It is possible to prevent rust from occurring on the disc brake on the inner surface side. Moreover, the protective film of a certain aspect which concerns on embodiment can improve the problem that a base material layer tears in the case of peeling.

[First Embodiment]
(Protective film)
The protective film according to the present embodiment is affixed to the front side (outside) of the disk part of the wheel of the wheel when the vehicle is transported over the sea for a long time, such as when the automobile is exported as described above. The plurality of openings formed in the cylinder are temporarily blocked to prevent rust of a disc brake rotor (not shown) disposed inside the wheel.

FIG. 1 is a front view of the protective film according to the first embodiment. FIG. 2 is a cross-sectional view of the protective film shown in FIG. In addition, the separator for protecting the adhesive layer is affixed on the protective film shown in FIG.1 and FIG.2. Further, the thicknesses and diameters of the layers shown in FIG. 2 do not necessarily represent actual scale ratios, but are merely schematically shown for convenience of explanation.

The protective film 10 according to the present embodiment has a disk (circular) shape. Moreover, the protective film 10 has the base material layer 12 and the adhesive layer 14 provided in the one surface of the base material layer 12, as shown in FIG. A separator 16 is attached to the surface of the pressure-sensitive adhesive layer 14 on the side where the base material layer 12 is not formed. The separator 16 prevents the surface of the pressure-sensitive adhesive layer 14 from being contaminated between the production of the protective film 10 and the use of the protective film 10 to reduce the adhesive force.

The separator 16 is provided with a knob 20 on the outer periphery. The knob 20 is for facilitating the separation of the separator 16 itself from the adhesive layer 14 when the protective film 10 is attached to the wheel. The protective film 10 has a notch 18 formed from the outer edge toward the inner side (center). In the protective film 10 according to the present embodiment, a plurality (for example, 18 in FIG. 1) of the cutout portions 18 are arranged at equal intervals. The cutout part should just be formed 1 (piece) or more in the outer edge part of a protective film. Moreover, as a shape of a notch part, it can be set as appropriate shapes, such as triangular shape and semicircle shape, for example.

(Adhesive layer)
The pressure-sensitive adhesive layer used in the protective film 10 according to the present embodiment is not particularly limited, but is preferably composed of, for example, a pressure-sensitive adhesive composition containing a (meth) acrylic polymer and a crosslinking agent. More preferably, the (meth) acrylic polymer comprises a (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms as a main component. The main component (meth) acrylic monomer constituting the (meth) acrylic polymer is not particularly limited as long as it is a (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms. Preferably, the carbon number is 1-12, more preferably, the carbon number is 2-10. By using the carbon number within the above-mentioned range, it is possible to secure the initial adhesiveness and the adhesiveness in a low temperature atmosphere such as winter, which is suitable for automobile wheel protection applications. In addition, it is a particularly preferable embodiment that the main component is a (meth) acrylic monomer having an alkyl group having 1 to 4 carbon atoms. The above (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms contains 40 to 80% by mass of the (meth) acrylic monomer having an alkyl group having 1 to 4 carbon atoms. It is preferably 50 to 75% by mass. By using the above-mentioned (meth) acrylic monomer having an alkyl group having 1 to 4 carbon atoms in the above range, the cohesive strength of the pressure-sensitive adhesive is improved, and adhesive residue can be prevented when peeling after use. It is valid.

Examples of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl ( (Meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, 2-ethylhexyl methacrylate, isoamyl (meth) Acrylate, n-pentyl (meth) acrylate, isopentyl (meth) acrylate, cyclopentyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, cyclooctyl (Meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, isomyristyl (meth) acrylate, n-tridecyl (Meth) acrylate, n-tetradecyl (meth) acrylate and the like. Of these, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate and the like are preferably used.

In the present embodiment, the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms may be used alone or in combination of two or more. The content of the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms based on the whole is preferably 40 to 90% by mass, and more preferably 50 to 80% by mass. If it exceeds 90% by mass, the cohesive force of the pressure-sensitive adhesive may be remarkably reduced. If it is less than 40% by mass, the initial adhesiveness is deteriorated, which is not preferable.

In addition to the (meth) acrylic monomer having an alkyl group having 1 to 14 carbon atoms, the (meth) acrylic polymer contains other monomer components as long as the performance of the protective film is not impaired. For example, a hydroxyl group-containing monomer can be used. By using the above-mentioned hydroxyl group-containing monomer, the crosslinkability with the cross-linking agent is increased, and adhesive residue can be prevented, which is effective. Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyhexyl (meth) acrylate, and 6-hydroxyhexyl. (Meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl acrylate, N-methylol (meth) Acrylamide, N-hydroxy (meth) acrylamide, vinyl alcohol, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monobi Such as ether, and the like. Of these, 2-hydroxyethyl (meth) acrylate and 2-hydroxyhexyl (meth) acrylate are preferably used.

In the present embodiment, the above hydroxyl group-containing monomer may be used alone or in combination of two or more, but the content of the above hydroxyl group-containing monomer with respect to the whole monomer is It is preferably 1 to 30% by mass, more preferably 2 to 20% by mass, and particularly preferably 3 to 10% by mass. If it exceeds 30% by mass, the initial adhesiveness may be deteriorated, and if it is less than 1% by mass, the cohesive force of the pressure-sensitive adhesive is significantly reduced, which is not preferable.

Furthermore, the above-mentioned (meth) acrylate having an alkyl group having 1 to 14 carbon atoms and a vinyl monomer copolymerizable with a hydroxyl group-containing monomer can also be contained. For example, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, cyano group-containing monomers, vinyl ester monomers, aromatic vinyl monomers and other cohesive force / heat resistance improving components, carboxyl group-containing monomers, acid anhydride group-containing monomers, Amide group-containing monomers, amino group-containing monomers, imide group-containing monomers, epoxy group-containing monomers, vinyl ether monomers and other components having functional groups that act as crosslinking points and other alkyl groups (meth) Acrylic monomers can be used as appropriate. These monomer compounds may be used alone or in admixture of two or more.

Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, (meth) And acryloyloxynaphthalene sulfonic acid.

Examples of the phosphate group-containing monomer include 2-hydroxyethylacryloyl phosphate.

Examples of the cyano group-containing monomer include acrylonitrile and methacrylonitrile.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl laurate, vinyl pyrrolidone, and the like.

Examples of the aromatic vinyl monomer include styrene, chlorostyrene, chloromethylstyrene, α-methylstyrene, and benzyl (meth) acrylate.

Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Among these, acrylic acid and methacrylic acid are particularly preferably used.

Examples of the acid anhydride group-containing monomer include maleic anhydride and itaconic anhydride.

Examples of the amide group-containing monomer include acrylamide, methacrylamide, diethyl (meth) acrylamide, N-vinylpyrrolidone, N-vinyl-2-pyrrolidone, N- (meth) acryloylpyrrolidone, N, N-dimethylacrylamide, N , N-dimethylmethacrylamide, N, N-diethylacrylamide, N, N-diethylmethacrylamide, N, N'-methylenebisacrylamide, N, N-dimethylaminopropylacrylamide, N, N-dimethylaminopropylmethacrylamide, etc. Can be given.

Examples of the amino group-containing monomer include N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N- (meth) acryloylmorpholine, and (meth) acrylic acid aminoalkyl ester. Etc.

Examples of the imide group-containing monomer include cyclohexylmaleimide, isopropylmaleimide, N-cyclohexylmaleimide, and itaconimide.

Examples of the epoxy group-containing monomer include glycidyl (meth) acrylate and allyl glycidyl ether.

Examples of the vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, and the like.

In the present embodiment, the copolymerizable vinyl monomer may be used alone or in combination of two or more, but the total content is a (meth) acrylic polymer. The total amount of the monomer components is preferably 10 to 50% by mass, more preferably 20 to 40% by mass. If it exceeds 50% by mass, the initial adhesiveness may be reduced, and if it is less than 10% by mass, the cohesive force of the pressure-sensitive adhesive may be remarkably reduced.

In addition, the glass transition temperature (Tg) of the (meth) acrylic polymer is 0 ° C. or lower (usually −100 ° C. or higher), preferably −10 ° C. or lower, and more preferably, because the adhesive performance is easily balanced. It is −20 ° C. or lower. When the glass transition temperature is higher than 0 ° C., the polymer is difficult to flow and the adherence to the adherend is insufficient, which tends to cause blisters generated between the automobile wheel and the adhesive layer of the protective film. In addition, the glass transition temperature (Tg) of a (meth) acrylic-type polymer can be adjusted in the said range by changing the monomer component and composition ratio to be used suitably. The glass transition temperature (Tg) (° C.) may be a general value. For example, Polymer Handbook Fourth Edition (edited by J. Brandup et al., 1999 John Wiley & Sons, Inc), Chapter VI, 198-253. The numerical value etc. which are described in the term can be used. In the case of a novel polymer, the peak temperature of loss tangent (tan δ) in a viscoelasticity measurement method (shear method, measurement frequency: 1 Hz) may be adopted as the glass transition temperature (Tg).

For the production of the (meth) acrylic polymer, a known radical polymerization method such as solution polymerization, bulk polymerization, and emulsion polymerization can be appropriately selected. Further, the (meth) acrylic polymer obtained may be any of a random copolymer, a block copolymer, a graft copolymer, and the like.

In solution polymerization, for example, methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, mesitylene, methanol, ethanol, n-propanol, isopropanol, water are used as polymerization solvents. Various aqueous solutions are used. The reaction is usually carried out at about 60 to 80 ° C. for about 4 to 10 hours under an inert gas stream such as nitrogen.

The polymerization initiator, chain transfer agent and the like used for radical polymerization are not particularly limited and can be appropriately selected and used.

Examples of the polymerization initiator used in the present embodiment include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [2 -(5-Methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis (2-methylpropionamidine) disulfate, 2,2'-azobis (N, N'-dimethylene) Isobutylamidine), 2,2′-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] hydrate (manufactured by Wako Pure Chemical Industries, Ltd., VA-057), azo initiators, potassium persulfate, Persulfates such as ammonium sulfate, di (2-ethylhexyl) peroxydicarbonate, di (4-tert-butylcyclohexyl) peroxydicarbonate , Di-sec-butylperoxydicarbonate, t-butylperoxyneodecanoate, t-hexylperoxypivalate, t-butylperoxypivalate, dilauroyl peroxide, di-n-octanoylper Oxide, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, di (4-methylbenzoyl) peroxide, dibenzoyl peroxide, t-butylperoxyisobutyrate, 1,1- Peroxide initiators such as di (t-hexylperoxy) cyclohexane, t-butyl hydroperoxide, hydrogen peroxide, combinations of persulfate and sodium bisulfite, combinations of peroxide and sodium ascorbate, etc. And redox initiators that combine peroxides and reducing agents. But it is not limited thereto.

The polymerization initiator may be used alone or in combination of two or more, but the total content is 0.005 to 1 part by mass with respect to 100 parts by mass of the monomer. The amount is preferably 0.02 to 0.5 parts by mass.

In this embodiment, a chain transfer agent may be used in the polymerization. By using a chain transfer agent, the molecular weight of the acrylic polymer can be appropriately adjusted.

Examples of the chain transfer agent include lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, and 2,3-dimercapto-1-propanol.

These chain transfer agents may be used alone or in admixture of two or more kinds, but the total content is 0.01 to 0.00 with respect to 100 parts by mass of the monomer. About 1 part by mass.

The pressure-sensitive adhesive composition used in the present embodiment can be obtained by cross-linking the above (meth) acrylic polymer using a cross-linking agent, so that it is more excellent in weather resistance, heat resistance, etc. It is valid. As the cross-linking agent used in the present invention, a compound having at least two functional groups capable of reacting (bonding) with the functional group of the above-mentioned functional group-containing (meth) acrylic monomer is used, and an isocyanate compound An epoxy compound, an oxazoline compound, a melamine resin, an aziridine derivative, a metal chelate compound, and the like can be used.

Of these, examples of the isocyanate compound include aromatic isocyanates such as tolylene diisocyanate and xylene diisocyanate, alicyclic isocyanates such as isophorone diisocyanate, aliphatic isocyanates such as hexamethylene diisocyanate, and emulsified isocyanates.

More specific isocyanate compounds include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate, alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate, and 2,4-tolylene diisocyanate. Aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate and xylylene diisocyanate, trimethylolpropane / tolylene diisocyanate trimer adduct (trade name Coronate L, manufactured by Nippon Polyurethane Industry), trimethylolpropane / hexamethylene diisocyanate Trimer adduct (product name: Coronate HL, manufactured by Nippon Polyurethane Industry), isocyanurate of hexamethylene diisocyanate Door body (manufactured by Nippon Polyurethane Industry Co., trade name: Coronate HX) isocyanate adducts such as, self-emulsifying type polyisocyanate (Nippon Polyurethane Industry Co., Ltd., trade name AQUANATE 200), and the like. These isocyanate compounds may be used alone or in combination of two or more.

Examples of the oxazoline compound include 2-oxazoline, 3-oxazoline, 4-oxazoline, 5-keto-3-oxazoline, and Epocros (manufactured by Nippon Shokubai). These compounds may be used alone or in combination.

Examples of the epoxy compound include N, N, N ′, N′-tetraglycidyl-m-xylenediamine (trade name: TETRAD-X, manufactured by Mitsubishi Gas Chemical) and 1,3-bis (N, N-diglycidylamino). Methyl) cyclohexane (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Co., Inc.), polyglycidylamine compounds such as tetraglycidyldiaminodiphenylmethane, triglycidyl-p-aminophenol, diglycidylaniline, and diglycidyl-o-toluidine. . These compounds may be used alone or in combination.

Examples of the melamine resin include hexamethylol melamine and water-soluble melamine resin.

Examples of the aziridine derivative include a commercial name HDU (manufactured by Mutual Yakuko), a brand name TAZM (manufactured by Mutual Yakuko), a brand name TAZO (manufactured by Mutual Yakuko), and the like. These compounds may be used alone or in combination.

Examples of the metal chelate compound include aluminum, iron, tin, titanium, and nickel as metal components, and acetylene, methyl acetoacetate, and ethyl lactate as chelate components. These compounds may be used alone or in combination.

The content of these crosslinking agents is appropriately selected as a protective film depending on the balance with the (meth) acrylic polymer to be crosslinked. In order to obtain sufficient weather resistance and heat resistance due to the cohesive strength of the (meth) acrylic polymer, it is preferable to contain 0.1 to 6 parts by mass with respect to 100 parts by mass of the (meth) acrylic polymer. The content is more preferably 0.2 to 4 parts by mass, and particularly preferably 0.4 to 2 parts by mass. When the content of the cross-linking agent is less than 0.1 parts by mass, the cross-linking by the cross-linking agent is insufficient, the solvent insoluble content tends to decrease, and the cohesive force of the pressure-sensitive adhesive layer is reduced. There is a tendency to cause the rest. On the other hand, when the content exceeds 6 parts by mass, the initial adhesive force of the pressure-sensitive adhesive layer is insufficient, the cohesive force of the polymer is large, the fluidity is lowered, and the wetness to the adherend becomes insufficient. , Tend to cause peeling.

In order to provide weather resistance to the protective film of the present embodiment, a weather stabilizer can be contained in the pressure-sensitive adhesive layer. The above-mentioned weather stabilizer refers to an ultraviolet absorber, a light stabilizer, or an antioxidant, and these compounds may be used alone as a weather stabilizer, or a mixture of two or more thereof. May be. By using the above-mentioned anti-wrinkle stabilizer, the film can be prevented from being peeled off and adhesive residue can be prevented after long-term storage with the protective film of the present embodiment attached to the wheel.

Examples of the UV absorber include benzotriazole UV absorbers, triazine UV absorbers, benzophenone UV absorbers, salicylate UV absorbers, and cyanoacrylate UV absorbers.

Specific examples of the ultraviolet absorber include, for example, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetrabutyl) -6- (2H-benzotriazole)], 2- (4,6-diphenyl-1,3 5-Triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydride Examples thereof include roxybenzoate, 4-t-butylphenyl salicylate, and ethyl-2-cyano-3,3-diphenyl acrylate. These ultraviolet absorbers may be used alone or in combination of two or more.

Among the above ultraviolet absorbers, it is preferable to use a benzotriazole ultraviolet absorber. In the case of using a benzotriazole-based ultraviolet absorber, weather resistance can be further improved, so that it is possible to further prevent the adhesive force from being reduced by bleeding of the ultraviolet absorber. As a result, even after the protective film is attached to the wheel, the film can be peeled off from the wheel during traveling due to a decrease in the adhesive force even when stored for a long period of time. This can be sufficiently prevented. Moreover, the adhesive residue after long-term storage can be sufficiently prevented.

In the pressure-sensitive adhesive layer, the content of the ultraviolet absorber is preferably 0.05 to 2 parts by mass with respect to 100 parts by mass of the resin solid content of the acrylic pressure-sensitive adhesive contained in the pressure-sensitive adhesive layer. The amount is more preferably 0.1 to 1.5 parts by mass. If it is less than 0.05 parts by mass, the effect of improving weather resistance may not be obtained. If it exceeds 2 parts by mass, the UV absorber may bleed.

As the light stabilizer, conventionally known light stabilizers can be used. For example, known light stabilizers such as hindered amine light stabilizers and benzoate light stabilizers can be appropriately used. In particular, when using a hindered amine light stabilizer (HALS: HindAmine Light Stabilizer), it is possible to further improve the weather resistance, so that the adhesive strength decreases due to bleeding of the light stabilizer. Can be prevented. As a result, even after the protective film is attached to the wheel, the film can be peeled off from the wheel during traveling due to a decrease in the adhesive force even when stored for a long period of time. This can be sufficiently prevented. Moreover, the adhesive residue after long-term storage can be sufficiently prevented.

Examples of the above-mentioned hindered amine light stabilizer include, for example, bis- (2,2,6,6-tetramethyl-4-piperidyl) sebacate, [dimethyl-1- (2-hydroxyethyl) -4-succinate]. Hydroxy-2,2,6,6-tetramethylpiperidine] condensate, 1,2,2,6,6-pentamethyl-4-piperidyl-tridecyl-1,2,3,4-butanetetracarboxylate, 1, 2,2,6,6-pentamethyl-4-piperidinol and 3,9-bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,10-tetraspiro [5,5] undecane and butanetetra Examples include esters with carboxylic acids. These light stabilizers may be used alone or in combination of two or more.

Examples of the hindered amine light stabilizer described above include reactive types such as ADK STAB LA-82 and LA-87 manufactured by Asahi Denka Co., Ltd., Hostabin N-20 manufactured by Hoechst Japan, and Tomisorp 77 manufactured by Yoshitomi Fine Chemical Co., Ltd. And a monomer type such as Sanol LS-770 manufactured by Sankyo Lifetech Co., and an oligomer type such as Uvinal 5050H manufactured by BSF Japan.

In the pressure-sensitive adhesive layer, the content of the light stabilizer is preferably 0.05 to 2 parts by mass with respect to 100 parts by mass of the resin solid content of the acrylic pressure-sensitive adhesive contained in the pressure-sensitive adhesive layer. The amount is more preferably 0.05 to 1.5 parts by mass. If it is less than 0.05 parts by mass, the effect of improving weather resistance may not be obtained. If it exceeds 2 parts by mass, the light stabilizer may bleed.

As the antioxidant, for example, a known antioxidant such as a hindered phenol-based antioxidant, a phosphorus-based processing heat stabilizer, a lactone-based processing heat stabilizer, a sulfur-based heat stabilizer can be appropriately used. These antioxidants may be used alone or in combination of two or more.

The addition amount of the antioxidant is preferably 3 parts by mass or less, more preferably 1 part by mass or less, and still more preferably about 0.01 to 0.5 parts by mass with respect to 100 parts by mass of the base polymer of each resin layer. It is.

Furthermore, a tackifier may be added to the pressure-sensitive adhesive composition. The tackifier described above is not particularly limited, and those conventionally used for pressure-sensitive adhesives can be used. For example, xylene resin, rosin, polymerized rosin, hydrogenated rosin, modified rosin such as rosin ester Resins; terpene resins such as terpene resins, terpene phenol resins, and rosin phenol resins; aliphatic, aromatic, and alicyclic petroleum resins; coumarone resins, styrene resins, alkylphenol resins, and the like. Among these, a rosin resin, an aromatic petroleum resin, and a terpene phenol resin are preferable from the viewpoint of excellent adhesion to an automobile wheel such as an aluminum wheel. These may be used alone or in combination of two or more.

In the pressure-sensitive adhesive layer, the content of the tackifier is preferably 1 to 100 parts by mass with respect to 100 parts by mass of the resin solid content of the acrylic pressure-sensitive adhesive contained in the pressure-sensitive adhesive layer. The amount is preferably 5 to 50 parts by mass. There exists a possibility that the adhesive force of an adhesive layer may become inadequate that it is less than 1 mass part. When the amount exceeds 100 parts by mass, when the protective film is peeled off from the automobile wheel, the film cannot be peeled cleanly from the wheel, and there is a possibility that glue remains on the wheel.

Furthermore, the pressure-sensitive adhesive composition may contain other known additives, such as powders such as colorants and pigments, dyes, surfactants, plasticizers, surface lubricants, leveling agents, Surfactants, softeners, antistatic agents, inorganic or organic fillers, metal powders, particles, foils, and the like can be added as appropriate according to the intended use. Moreover, the usage-amount normally used in the field | area of the surface protection material can be used for the compounding quantity of these arbitrary components.

As a method for producing the protective film of the present embodiment, a method of forming an adhesive layer on a base material layer can be used. For example, a method of applying the pressure-sensitive adhesive composition to a peeled separator, drying and removing the polymerization solvent, and transferring the pressure-sensitive adhesive layer to the base material layer, or the pressure-sensitive adhesive composition on the base material layer It is produced by, for example, a method of forming a pressure-sensitive adhesive layer on a substrate layer by applying and removing a polymerization solvent by drying. Thereafter, curing (aging treatment) may be performed for the purpose of adjusting the component transfer of the pressure-sensitive adhesive layer or adjusting the crosslinking reaction. Moreover, when producing a protective film by applying the pressure-sensitive adhesive composition on the base material layer, one or more solvents (other than the polymerization solvent) in the pressure-sensitive adhesive composition can be applied uniformly on the base material layer ( (Solvent) may be newly added.

Examples of the solvent used in this embodiment include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, mesitylene, methanol, ethanol, n-propanol, isopropanol, water And various aqueous solutions. These solvents may be used alone or in combination of two or more.

Also, as a method for forming the pressure-sensitive adhesive layer of the present embodiment, a known method used for the production of a surface protective film is used. Specifically, for example, methods such as roll coat, kiss roll coat, gravure coat, reverse coat, roll brush, spray coat, dip roll coat, bar coat, knife coat, air knife coat, extrusion coat method using a die coater, etc. Can be given.

The thickness of the above-mentioned pressure-sensitive adhesive layer is not particularly limited and is appropriately selected. For example, the thickness is preferably 3 to 50 μm, and more preferably 5 to 40 μm. Thereby, the adhesiveness and adhesive force of an adhesive layer and the wheel for motor vehicles can be improved. If the thickness is less than 3 μm, sufficient adhesion and adhesive strength may not be obtained. Even if it exceeds 50 μm, an improvement in the effect cannot be expected, which may be disadvantageous economically.

The surface of the pressure-sensitive adhesive layer may be subjected to a surface treatment such as a corona treatment, a plasma treatment, or an ultraviolet treatment.

In the present embodiment, the gel fraction of the pressure-sensitive adhesive layer measured based on the measurement method described later is preferably 60 to 95% by mass, more preferably 70 to 93% by mass, and particularly preferably 75. ~ 90% by mass. If the gel fraction is less than 60% by mass, the cohesive force is reduced, so that it may be inferior in impact resistance (durability) or the like, and if it exceeds 95% by mass, the adhesion may be inferior.

The gel fraction of the pressure-sensitive adhesive layer can be adjusted by the addition amount of the crosslinking agent, the crosslinking treatment conditions (heat treatment temperature, heating time, etc.) and the like. The crosslinking treatment may be performed at the temperature during the drying step of the pressure-sensitive adhesive layer, or a separate crosslinking treatment step may be provided after the drying step.

In the present embodiment, the weight average molecular weight (Mw) of the sol content of the pressure-sensitive adhesive layer measured based on the measurement method described later is preferably 5000 to 300,000, more preferably 10,000 to 200,000. It is a range. In the case of being in the above-mentioned range, in addition to the balance between the adhesive property and cohesiveness of the pressure-sensitive adhesive composition, it is possible to prevent contamination of the adherend (automobile wheel) with a low molecular weight material, which is preferable. .

The degree of swelling of the pressure-sensitive adhesive layer measured based on the measurement method described later in the present embodiment is preferably 5 to 40 times, more preferably 10 to 30 times. When the degree of swelling is outside the above range, the effect of improving the adhesion to the adherend (automobile wheel) tends to be poor.

When the surface of the pressure-sensitive adhesive layer used in the protective film of the present embodiment is exposed, even if the pressure-sensitive adhesive layer is protected with a sheet (release sheet, separator, release liner) subjected to release treatment until it is put to practical use. Good.

Examples of constituent materials of the separator (release sheet, release liner) include plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films, porous materials such as paper, cloth, and nonwoven fabric, nets, foam sheets, metal foils, and Although suitable thin leaf bodies, such as these laminates, can be mentioned, paper is preferably used in terms of excellent surface smoothness.

The film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer, and for example, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer. Examples thereof include a coalesced film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film.

The thickness of the separator is usually about 5 to 200 μm, preferably about 5 to 100 μm.

For the separator, if necessary, release agent and antifouling treatment with silicone, fluorine, long chain alkyl or fatty acid amide release agent, silica powder, etc., coating type, kneading type, vapor deposition type It is also possible to carry out antistatic treatment such as. In particular, the release property from the pressure-sensitive adhesive layer can be further improved by appropriately performing a release treatment such as silicone treatment, long-chain alkyl treatment, or fluorine treatment on the surface of the separator.

In the above manufacturing method, the release-treated sheet (release sheet, separator, release liner) can be used as it is as a separator for the protective film, and the process can be simplified.

Further, the automobile wheel protective film according to the present embodiment is formed by forming the pressure-sensitive adhesive layer having the above-described configuration on one side or both sides of the base material layer.

In the present embodiment, the film means a planar material, and usually includes what is called a tape or a sheet.

(Base material layer)
As the base material layer according to the present embodiment, a polyethylene resin composed of a polyethylene resin from the viewpoint of weather resistance (water resistance, moisture resistance, heat resistance, etc.), impact resistance (tear strength, etc.) and transparency. It is preferable to use a layer. Examples of the polyethylene resin layer include ethylene polymers (low density, high density, linear low density polyethylene resin, etc.), olefin polymers such as ethylene / α-olefin copolymers, ethylene / vinyl acetate copolymers, ethylene Examples include resin layers composed of olefin-based polymers of ethylene and other monomers such as methyl methacrylate copolymer, ethylene / propylene copolymer, ethylene / propylene / α-olefin copolymer. More preferably. Use of these polyethylene layers is preferable in terms of weather resistance, impact resistance, and transparency.

Further, the base material layer is particularly preferably a single layer made of only a low density polyethylene resin. A base material layer formed by blending a plurality of different types of polyolefin resins such as polyethylene and polypropylene becomes brittle and may cause a problem of tearing when the aforementioned film (surface protective film) is peeled off. In addition, when peeling at a high speed, tearing of the base material layer occurs, which is not preferable.

The base material layer may be a resin stretched or non-stretched. Moreover, the said polyethylene-type resin layer may be used independently, and 2 or more types may be bonded together and used.

The thickness of the base material layer is not particularly limited, but is preferably 10 to 200 μm, for example, and more preferably 30 to 150 μm. If it is less than 10 μm, it is inferior in pasting workability.

In addition, in order to improve adhesion to other resin layers, pressure-sensitive adhesive layers, undercoats, etc., the surface of the base material layer (or each resin layer) is subjected to surface treatment such as corona treatment, plasma treatment, or ultraviolet treatment. You may go. Moreover, you may perform a back surface process to a base material layer (resin layer).

Further, from the viewpoint of weather resistance, the base material layer can also be appropriately treated with a weather stabilizer within a range that does not impair the transparency of the present invention.

The treatment using the above-mentioned weathering stabilizer (ultraviolet absorber, light stabilizer, antioxidant) can be carried out by coating or transferring treatment on the surface of the resin layer, kneading into the resin layer, or the like.

In addition, an optional additive such as a flame retardant, inert inorganic particles, organic particles, a lubricant, an antistatic agent, or a pigment can be blended in the base material layer as long as the effects of the present embodiment are not impaired.

Moreover, since this embodiment is used for a surface protective film for automobile wheels, it is preferable that the base material layer is a resin film having heat resistance and solvent resistance and flexibility. When the base material layer has flexibility, the pressure-sensitive adhesive composition can be applied by a roll coater or the like, and can be wound into a roll.

In addition, the base material layer may include a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based mold release agent, mold release with silica powder, and antifouling treatment, acid treatment, alkali treatment, Antistatic treatment such as primer treatment, coating type, kneading type, and vapor deposition type can also be performed.

In addition, a surface coat layer, for example, a hard coat layer or a soft coat layer can be appropriately provided on the base material layer as necessary. Examples of such a surface coating layer include a thermosetting type or a chemical reaction curing type such as a silicone type, a melamine type, a urethane type, a silane type, and an acrylate type. Thereby, it can be set as the surface protection film for motor vehicles more excellent in abrasion resistance, chemical resistance, a weather resistance, anti-fogging property, etc.

In addition, the protective film of the present embodiment has a function excellent in weather resistance, adhesion reliability, transparency, and impact resistance by using the pressure-sensitive adhesive layer and the base material layer. It is suitable for a protective film that has undergone a long-term storage and distribution process.

In the present embodiment, the protective film means a film that protects the wheel surface of an automobile or the like indoors / outdoors, such as a small automobile, a normal passenger car, a large automobile, a special vehicle, a heavy machine, or a motorcycle. These include those used for protecting the wheel surface used in various types of vehicles and exhibiting the rust prevention effect of the disc brake on the inner surface side of the wheel.

The material of the automobile wheel to which the protective film is attached is not particularly limited as long as it is used as a material for the wheel. Among these, an aluminum wheel is preferred because it has a relatively large adhesive force after being stored for a long time in a pasted state and can sufficiently prevent adhesive residue.

When such a protective film is affixed to an automobile wheel, wrinkles may occur at the outer peripheral edge as described above. Therefore, the wind pressure at the time of driving | running | working a vehicle may produce the malfunction which a protective film peels off from a wheel starting from the wrinkle. Therefore, the cutout portion 18 is formed in the protective film 10 according to the present embodiment. Thereby, when sticking a protective film on a wheel with an unevenness | corrugation or a curved surface, since a wrinkle is folded by the notch part 18, generation | occurrence | production of the wrinkle by the shape of a wheel is suppressed. And since generation | occurrence | production of a wrinkle is suppressed, possibility that a protective film will peel from a wheel by the wind pressure which generate | occur | produces at the time of a motor vehicle drive falls. That is, the protective film 10 can maintain a stable attachment state to a wheel of a vehicle or the like.

Moreover, it is preferable that the notch 18 has an R-shaped tip 18a (see FIG. 1) close to the center. By making the front end portion close to the center portion into an R shape, for example, when the protective film 10 attached to the wheel is peeled off, the front end portion 18a of the cutout portion 18 is not easily torn.

Next, although the suitable production method of the protective film which concerns on this Embodiment is demonstrated below, a manufacturing method and material are not limited to these.

(Adjustment of water-dispersed acrylic polymer)
In a reaction vessel equipped with a cooling tube, a nitrogen introduction tube, a thermometer and a stirrer, 58 parts of butyl acrylate, 40 parts of butyl methacrylate, 2.0 parts of acrylic acid, and 2,2′-azobis (2-amidino as a polymerization initiator) Propane) dihydrochloride 0.03 part, polyoxyethylene alkylphenyl ether phosphoric acid 2.4 part, polyoxyethylene nonyl phenyl ether ammonium sulfate 0.8 part and water 150 part as an emulsifier, emulsion polymerization, 10 The aqueous dispersion type acrylic polymer (acrylic polymer emulsion) was obtained by adjusting the pH to 8 with mass% ammonia water.

(Adjustment of adhesive solution)
As a water-soluble crosslinking agent containing an oxazoline group per 100 parts of its solid content (water-dispersed copolymer) in the water-dispersed acrylic polymer, the product name “Epocross WS-500” of Nippon Shokubai Co., Ltd. ( Oxazoline group equivalent: 220 g · solid / eq.) 2.0 parts, 2.0 parts of the trade name “TINUVIN 765” of Ciba Japan Co., Ltd. as a light stabilizer are mixed, and water-dispersed pressure-sensitive adhesive composition A It was.

(Preparation of wheel protection film)
Using a low-density polyethylene resin (Petrocene 180, density: 0.922 g / cm ³ , manufactured by Tosoh Corporation), the film was extruded from a die heated to 160 ° C. by an inflation method to form a 75 μm polyethylene film. A corona treatment was applied to one side of the. The above-mentioned water-dispersed pressure-sensitive adhesive A was applied to this corona-treated surface and heated at 80 ° C. for 1 minute to form a pressure-sensitive adhesive layer having a thickness of 10 μm, thereby producing a wheel protective film. About the obtained wheel protective film, 18 triangular notch parts were formed in the outer edge part as shown in FIG. 1 at equal intervals, and the wheel protective film which concerns on 1st Embodiment was produced.

The protective film obtained in this embodiment has a low-density polyethylene resin that is a base material layer and an adhesive layer provided on one surface of the base material layer. Since this pressure-sensitive adhesive layer is a water-dispersed pressure-sensitive adhesive composition containing a light stabilizer, even if the pressure-sensitive adhesive layer is left on the tire or wheel for a long time under sunlight. The performance degradation of the layer is suppressed.

Further, when the protective film obtained in the present embodiment is attached to a wheel having unevenness or a curved surface, wrinkles are folded by the notch portion 18, and thus generation of wrinkles due to the shape of the wheel is suppressed. As a result, the protective film 10 can maintain a stable state of being attached to a wheel of a vehicle or the like.

[Second Embodiment]
The protective film according to each embodiment below is the same as the protective film 10 according to the first embodiment in that the base material layer 12, the pressure-sensitive adhesive layer 14, and the separator 16 are laminated. The material is the same as in the first embodiment.

FIG. 3 is a front view of the protective film according to the second embodiment. In FIG. 3, the separator is omitted. The protective film 22 according to the present embodiment has a circular shape. The protective film 22 has a cut portion 24 formed inward from the outer edge. In the protective film 22 according to the present embodiment, a plurality (for example, 18 in FIG. 3) of the cut portions 24 are arranged at equal intervals.

The cut portion may be formed by one (piece) or more from the outer edge of the protective film toward the inside. Moreover, as a shape of a notch part, it can be set as appropriate shapes, such as linear form and wavy line form, for example.

Thus, when a protective film is applied to a wheel having irregularities or a curved surface, wrinkles are folded by the cut portion 24, so that generation of wrinkles due to the shape of the wheel is suppressed. And since generation | occurrence | production of a wrinkle is suppressed, possibility that a protective film will peel from a wheel by the wind pressure which generate | occur | produces at the time of a motor vehicle drive falls. That is, the protective film 22 can maintain a stable attachment state to a wheel of a vehicle or the like.

In the protective film 22, a tear preventing portion 26 connected to the cut portion 24 is formed at the inner end of the cut portion 24. The tear preventing unit 26 is an opening sectioned by a curve. Therefore, for example, when the protective film 22 attached to the wheel is peeled off, the protective film 22 is not easily torn by the tear preventing portion 26 provided at the tip of the cut portion 24.

[Third Embodiment]
FIG. 4 is a front view of the protective film according to the third embodiment. The protective film 28 according to the present embodiment is the same as the protective film 10 according to the first embodiment, except that a ventilation portion 30 through which air can pass from one surface to the other surface is formed. In FIG. 4, the separator is omitted.

By sticking the protective film 28 in which the ventilation part 30 is formed on the wheel, the pressure difference between the inside and outside of the wheel is alleviated and the peeling of the protective film from the wheel is suppressed. In addition, the ventilation part 30 is formed in the state in which the protective film 28 and the separator were integrated from the ease of manufacture. Therefore, although the ventilation part 30 is formed also in the separator, the ventilation part is not necessarily required for the separator.

Note that a plurality of ventilation portions 30 according to the present embodiment are formed. Thereby, compared with the case where the ventilation part 30 is one, the pressure difference inside and outside of a wheel is relieve | moderated more. Moreover, the some ventilation | gas_flowing part 30 is arranged in cyclic | annular form. In particular, the plurality of ventilation portions 30 according to the present embodiment are arranged concentrically with respect to the center of the protective film 10. Moreover, the some ventilation | gas_flowing part 30 is arranged at equal intervals. Thereby, the flow of air passing through the ventilation portion 30 so as to relieve the pressure difference between the inside and outside of the wheel is generated at equal intervals in the circumferential direction of the protective film 10. Therefore, since the force in the direction of peeling from the wheel acts uniformly on the adhesive surface of the protective film 10, the protective film 10 is difficult to peel from the wheel.

[Fourth Embodiment]
FIG. 5 is a front view of the protective film according to the fourth embodiment. The protective film 32 according to the present embodiment is the same as the protective film 22 according to the second embodiment except that a ventilation portion 30 through which air can pass from one surface to the other surface is formed. In FIG. 5, the separator is omitted. The function of the ventilation portion 30 in the protective film 32 according to the present embodiment is as described in the third embodiment.

[Fifth Embodiment]
FIG. 6 is a front view of the protective film according to the fifth embodiment. As with the protective film 28 according to the third embodiment, the protective film 34 according to the present embodiment has a plurality of ventilation portions 36 formed in a ring at regular intervals. The protective film 28 according to the third embodiment and the protective film 34 according to the fifth embodiment have the same configuration except that the shape of the ventilation portion is different. The ventilation portion 36 according to the fifth embodiment is a slit formed in an arc shape. Therefore, when the wheel is stationary, it is difficult for water and contaminants to enter the inside of the wheel to which the protective film 34 is attached. Further, in the state where the wheel is rotating, the arc-shaped slit is deformed by the flow of air passing through the ventilation portion 36 and the like, and the air is more easily distributed.

In addition, although the circular arc is formed toward the outside from the center of the protective film 34, the circular arc may be formed toward the center of the protective film 34.

[Sixth Embodiment]
FIG. 7 is a front view of the protective film according to the sixth embodiment. As with the protective film 32 according to the fourth embodiment, the protective film 38 according to the present embodiment has a plurality of ventilation portions 36 formed annularly at equal intervals. The protective film 32 according to the fourth embodiment and the protective film 38 according to the sixth embodiment have the same configuration except that the shape of the ventilation portion is different. The ventilation part 36 according to the sixth embodiment is also a slit formed in an arc shape. The function of the ventilation portion 36 in the protective film 38 according to the present embodiment is as described in the fifth embodiment.

The present invention has been described based on each embodiment. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are also within the scope of the present invention. is there.

In addition, what is necessary is just to select suitably the number and position, such as a notch part of a protective film which concerns on each embodiment, a notch part, and a ventilation | gas_flowing part, according to the magnitude | size and shape of the wheel which adheres a protective film.

10 protective film, 12 base material layer, 14 adhesive layer, 16 separator, 18 notch, 18a tip, 22 protective film, 24 cut, 26 tear prevention, 28 protective film.

The present invention can be used for a protective film attached to a wheel of a vehicle such as an automobile.

Claims

A base material layer;
A protective film for a wheel having a pressure-sensitive adhesive layer provided on one surface of the base material layer,
The wheel protective film is characterized in that one or more incisions are formed from the outer edge toward the inner side.
2. The protective film for a wheel according to claim 1, wherein a tear preventing portion connected to the cut portion is formed at an inner end portion of the cut portion.
3. The protective film for a wheel according to claim 2, wherein the tear preventing portion is an opening section defined by a curve.
The wheel protective film is circular,
4. The wheel protective film according to claim 1, wherein a plurality of the cut portions are arranged at equal intervals. 5.
A base material layer;
A protective film for a wheel having a pressure-sensitive adhesive layer provided on one surface of the base material layer,
The wheel protective film is characterized in that one or more notches are formed in an outer edge portion.
6. The protective film for a wheel according to claim 5, wherein the cutout portion has an R shape at a tip portion close to the center.
The wheel protective film is circular,
The wheel protective film according to claim 5 or 6, wherein a plurality of the notches are arranged at equal intervals.
The wheel protective film according to any one of claims 1 to 7, wherein the protective film for a wheel is formed with a ventilation portion through which air can pass from one surface to the other surface.
The wheel protective film according to claim 8, wherein the ventilation portion is a slit.
The wheel protective film according to claim 9, wherein the slit is formed in an arc shape.