JP5655342B2 - Laminated body - Google Patents

Description

  The present invention relates to a laminate.

  Conventionally, in order to impart weather resistance to outdoor structures, various weather resistance additives such as ultraviolet absorbers and light stabilizers have been added to resin layers such as curable resin layers to improve weather resistance. Resin films have been used. However, although such a resin film has improved weather resistance, there has been a problem that yellowing caused by yellowing due to an ultraviolet absorber or a photocuring agent occurs. Such yellowing significantly impairs the aesthetic appearance.

  In response to such problems, a polyolefin resin film for electron beam irradiation has been proposed that is excellent in weather resistance and does not easily discolor, such as yellowing, when irradiated with an electron beam (see Patent Document 1). In order to prevent yellowing with time, a polymerizable unsaturated electron beam curable coating composition has been proposed (see Patent Document 2).

By the way, with diversification of consumer needs and increasing performance requirements, outdoor structures exhibiting white or transparency tend to increase, and reduction of yellowing under more severe conditions is required. In particular, when a resin film is used for the purpose of protecting a member or part exposed to sunlight of a white or transparent outdoor structure, the required performance for the resin film is particularly severe because the yellowing of the resin film tends to be noticeable. It has become a thing.
Under such circumstances, the ones proposed in Patent Document 1 and Patent Document 2 may be yellowed or cracked or detached from the layer provided on the base material. However, there is a need for something that can be adequately addressed.

JP 2001-40113 A JP 2002-69331 A

  The present invention provides a laminate excellent in weather resistance that does not yellow even under extremely harsh environments and does not cause cracking or detachment of a layer provided on a substrate when using the laminate for an outdoor structure. It is intended to do.

As a result of intensive studies to achieve the above object, the inventors of the present invention, in a laminate having a surface protective layer formed by crosslinking and curing a primer layer and an ionizing radiation curable resin composition on a substrate, It has been found that the object can be achieved when the surface protective layer contains a hindered amine light stabilizer and at least one of the primer layer and the surface protective layer contains a predetermined antioxidant. The present invention has been completed based on such findings.
That is, the gist of the present invention is as follows.

1. A laminate formed by laminating at least a primer layer and a surface protective layer on a substrate, wherein the primer layer and / or the surface protective layer is white or transparent, and the surface protective layer is hindered amine light. A hindered phenol-based antioxidant having a primer layer and / or a surface protective layer having a — (CH ₂ ) ₂ —COO— group; A laminate comprising at least one selected from sulfur-based antioxidants.
2. 2. The laminate according to 1 above, wherein the primer layer exhibits a white color.
3. 3. The laminate according to 2 above, wherein the primer layer contains rutile type titania.
4). 4. The laminate according to any one of 1 to 3, wherein the primer layer further contains a hindered amine light stabilizer.
5. 2. The laminate according to 1 above, wherein the primer layer is transparent and contains a hindered amine light stabilizer.
6). The laminate according to any one of 1 to 5 above, wherein the content of the light stabilizer in the surface protective layer is 0.1 to 10 parts by mass with respect to 100 parts by mass of the ionizing radiation curable resin.

  ADVANTAGE OF THE INVENTION According to this invention, the laminated body excellent in the weather resistance which does not yellow, and does not generate | occur | produce the crack provided by the layer provided on a base material, or a peeling | exfoliation can be provided even in a very severe environment.

The laminate of the present invention is a laminate obtained by laminating at least a primer layer and a surface protective layer on a substrate, and the primer layer and / or the surface protective layer is white or transparent, A hinder in which the surface protective layer is formed by crosslinking and curing an ionizing radiation curable resin fat composition containing a hindered amine light stabilizer, and the primer layer and / or the surface protective layer has a — (CH ₂ ) ₂ —COO— group. It is characterized by containing at least one selected from a dophenol antioxidant and a sulfur antioxidant.

[Hindered amine light stabilizer]
In the laminate of the present invention, a hindered amine light stabilizer (HALS) is required to be used in the surface protective layer, and is preferably used in the primer layer.
Examples of hindered amine light stabilizers include N, N ′, N ″, N ″ ′-tetrakis- (4,6-bis- (butyl- (N-methyl-2,2,6,6-tetramethylpiperidine). -4-yl) amino) -triazin-2-yl) -4,7-diazadecane-1,10-diamine, dibutylamine 1,3,5-triazine N, N'-bis (2,2,6) , 6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N- (2,2,6,6-tetramethyl-4-piperidyl) butylamine polycondensate, poly [{6- (1 , 1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {( 2,2,6,6-tetramethyl-4-pipe Zyl) imino}], dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, 2,4-bis [N-butyl-N- (1-cyclohexyl) Oxy-2,2,6,6-tetramethylpiperidin-4-yl) amino] -6- (2-hydroxyethylamine) -1,3,5-triazine, bis (2,2,6,6) decanedioate -Reaction product of tetramethyl-1 (octyloxy) -4-piperidinyl) ester, 1,1-dimethylethyl hydroperoxide and octane, bis (2,2,6,6-tetramethyl-4-piperidyl) succinate Bis (2,2,6,6-tetramethylpiperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) 2- (3,5-di-tert Butyl-4-hydroxybenzyl) -2-butylmalonate, 1- [2- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propynyloxy] ethyl] -4- [3- ( 3,5-di-tert-butyl-4-hydroxyphenyl) propynyloxy] -2,2,6,6-tetramethylpiperidine, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate And methyl-1,2,2,6,6-pentamethyl-4-piperidyl-sebacate, bis (1-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, 1,2, 2,6,6-pentamethyl-4-piperidyl methacrylate, 1,2,2,6,6-pentamethyl-4-piperidyl acrylate, 2,2,6,6-tetramethyl-4 -Piperidyl methacrylate, 2,2,6,6-tetramethyl-4-piperidyl acrylate, 1,2,2,6,6-pentamethyl-4-iminopiperidyl methacrylate, 2,2,6,6, -tetramethyl- Examples include 4-iminopiperidyl methacrylate, 4-cyano-2,2,6,6-tetramethyl-4-piperidyl methacrylate, and 4-cyano-1,2,2,6,6-pentamethyl-4-piperidyl methacrylate. Etc. are preferable.

  Among these, decanedioic acid bis (2,2,6,6-tetramethyl-1- (octyloxy) -4-piperidinyl) ester, reaction product of 1,1-dimethylethyl hydroperoxide and octane, 2, 4-Bis [N-butyl-N- (1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) amino] -6- (2-hydroxyethylamine) -1,3,5- Triazine, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, 2,2,6,6-pentamethyl-4-piperidyl methacrylate and the like are more preferable, and these may be used alone or in combination. Can do. In addition, these are “Tinubin 123 (trade name)”, “Tinubin 152 (trade name)” (made by Ciba Japan Co., Ltd.), “LA-82 (trade name)”, “LA-87 (trade name), respectively. ”” (Above, manufactured by ADEKA Corporation).

The content of the light stabilizer contained in the surface protective layer and the primer layer is preferably in the range of 0.1 to 10 parts by mass, more preferably 0.2 to 8 parts by mass with respect to 100 parts by mass of the resin component constituting each layer. Preferably, 0.5-5 mass parts is further more preferable, and 0.5-3 mass parts is especially preferable. When the content of the light stabilizer is within the above range, the effect as a light stabilizer is obtained, and there is no problem such as bleeding.
Here, the resin component constituting each layer refers to the ionizing radiation curable resin that constitutes the surface protective layer if it is a surface protective layer, and constitutes the primer layer and the substrate, respectively, if it is a primer layer and a substrate. It means the resin content. Hereinafter, the same meaning is used when the same expression is used.

  The surface protective layer and the primer layer can contain other light stabilizers in addition to the hindered amine light stabilizers. Examples of other light stabilizers include acrylate, nickel, oxamide, salicylate, benzophenone, benzotrizole, and cyanoacrylate.

[Antioxidant]
In the laminate of the present invention, the primer layer and / or the surface protective layer contains at least one selected from a hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group and a sulfur-based antioxidant. It takes a thing.

"- (CH ₂₎ a hindered phenol antioxidant having ₂ -COO- group"
The hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group used in the present invention is pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate. ], Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,6-hexanediol bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) Propionate], 3,6-dioxaoctane-1,8-diolbis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, N, N′-hexane-1,6-diylbis [ Preferred examples include 3- (3,5-di-tert-butyl) -4-hydroxyphenyl] propionamide. These can be used alone or in combination.

Among the above, as the hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group, pentaerythritol tetrakis [from the viewpoint of compatibility with a weather-resistant primer and a surface protective phase resin [ 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate is preferred. These can be obtained as “IRGANOX 1010 (trade name)” and “IRGANOX 1076 (trade name)” (manufactured by Ciba Japan Co., Ltd.).

《Sulfur-based antioxidant》
Examples of the sulfur-based antioxidant used in the present invention include dilauryl-3,3′-thiodipropionate, tridecyl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, Stearyl-3,3′-thiodipropionate, laurylstearyl-3,3′-thiodipropionate, neopentanetetrayltetrakis (3-laurylthiopropionate), 2,4-bis (dodecylthiomethyl) -6-methylphenol, thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and the like are preferably mentioned, and these can be used alone or in combination. .
Among these, as the sulfur-based antioxidant, tridecyl-3,3′-thiodipropionate, dilauryl-3,3′-thiodipropionate, 2,4-bis (dodecylthiomethyl) -6- Methylphenol is preferred. In addition, these are “ADK STAB AO-503A (trade name)” (manufactured by ADEKA Corporation), “DLTP Yoshitomi (trade name)” (manufactured by API Corporation), “Irganox 1726 (trade name)” (Ciba)・ Made as Japan Co., Ltd.).

  The content of the antioxidant contained in the surface protective layer and the primer layer is preferably in the range of 0.1 to 10 parts by mass, more preferably 0.2 to 8 parts by mass with respect to 100 parts by mass of the resin component constituting each layer. Preferably, 0.5-5 mass parts is further more preferable, and 0.5-3 mass parts is especially preferable. If content of antioxidant is in the said range, the effect as antioxidant will be acquired and there will be no problems, such as a bleed.

Next, each component of the laminated body of this invention is demonstrated in detail.
[Base material]
The substrate used in the laminate of the present invention is not particularly limited as long as it is usually used as a weather-resistant laminate, but a plastic film is preferably used.
Plastic films include polyolefins such as polyethylene, polypropylene, and polymethylpentene; chlorine-containing resins such as polyvinyl chloride and polyvinylidene chloride; polyvinyl alcohol; vinyl chloride-vinyl acetate copolymer; ethylene-vinyl alcohol copolymer; Polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer; poly (meth) acrylate methyl, poly (meth) ethyl acrylate, poly (meth) acrylate butyl, etc. Poly (meth) acrylate; Polyamide such as nylon 6 and nylon 66; Cellulosic resin such as cellulose triacetate and cellophane; Polystyrene; Polycarbonate; Polyarylate; A thermoplastic resin film such as polyimide and the like. These may be a single layer of a film or a laminate composed of a plurality of films.
Of these substrates, polyester and polyolefin are preferable, and hydrolysis resistant polyethylene terephthalate (PET) and polypropylene are particularly preferable.

These base materials may be biaxially stretched, uniaxially stretched, or unstretched.
Moreover, as thickness of a base material, although it determines suitably according to the use for which a laminated body is used, it is the range of 10-1000 micrometers normally, and the range of 20-500 micrometers is preferable.
Furthermore, various additives such as a filler, a foaming agent, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, and a light stabilizer can be added to the substrate as necessary. Among these, as described above, the ultraviolet absorber is preferably a triazine-based ultraviolet absorber, and the benzotriazole-based ultraviolet absorber is contained to such an extent that yellowing due to electron beam irradiation is not affected. However, it is preferable not to contain a benzotriazole ultraviolet absorber. In addition, as a compounding method of a triazine type ultraviolet absorber, it can mix | blend by kneading into resin which comprises a base material, or making it copolymerize to resin which comprises a base material.

When using a plastic film as a base material, a physical or chemical surface treatment such as an oxidation method or an unevenness method is applied to one side or both sides as desired in order to improve the adhesion to the layer provided on the plastic film. Can be applied.
Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone / ultraviolet treatment method, and examples of the unevenness method include a sand blast method and a solvent treatment method. These surface treatments are appropriately selected depending on the type of substrate, but generally, a corona discharge treatment method is preferably used from the viewpoints of effects and operability.

[Primer layer]
The laminated body of this invention requires that the primer layer is laminated | stacked on the base material. The primer layer is a layer provided in order to improve adhesion between layers such as a base material and a surface protective layer and to impart concealability to the laminate of the present invention as necessary. The primer layer and the surface protective layer described later require that any one of them be at least white or transparent, and the primer layer is preferably white.
The resin constituting the primer layer is not particularly limited as long as it exhibits the above effects, and is an acrylic resin, vinyl chloride-vinyl acetate copolymer, polyester resin, polyurethane resin, chlorinated polypropylene resin, chlorinated polyethylene resin. And so on. Of these, polyurethane resin is a preferred resin in terms of adhesion and the like.

<Polyurethane resin>
As the polyurethane resin, for example, a two-component curable urethane resin can be used. The two-component curable urethane resin is a resin having a hydroxyl group at the terminal, obtained by reacting a polyol component with a polyisocyanate component, and preferred examples of the polyol component include polyether polyol, polyester polyol, polycarbonate polyol, and acrylic polyol. Can be mentioned. Among these, a copolymer using polycarbonate diol and polyester diol as the polyol component, and a copolymer using polycarbonate diol, polyester diol and acrylic polyol are more preferable.

In addition, as the two-component curable urethane resin, it is preferable in terms of weather resistance adhesion to use an aliphatic isocyanate or an alicyclic isocyanate as the isocyanate component. The isocyanate component in the urethane portion is also preferably an aliphatic isocyanate or an alicyclic isocyanate in terms of weather resistance adhesion. In addition, you may use together alicyclic isocyanate and aliphatic isocyanate.
As the alicyclic isocyanate, for example, IPDI (isophorone diisocyanate), hydrogenated MDI (hydrogenated diphenylmethane diisocyanate) and the like can be used. As the aliphatic isocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, or the like can be used.

(Acrylic-urethane block copolymer)
In the present invention, an acrylic-urethane block copolymer is also preferred. An acrylic-urethane block copolymer is a copolymer containing both blocks of an acrylic polymer component and a urethane portion. By including the acrylic polymer component, the adhesion with the surface protective layer made of an electron beam curable resin, which will be described in detail later, is improved. In addition, by including a urethane portion, the adhesion between the surface protective layer and the primer layer when using a two-component curable urethane resin is improved, and in particular, a urethane acrylate electron beam curable resin is used. The adhesion between the surface protective layer and the primer layer is also improved.
As the acrylic-urethane block copolymer, for example, (A) a hydroxyl group-containing acrylic polymer portion containing an acrylic monomer in the main chain and having a hydroxyl group at the terminal or side chain, (B) polycarbonate urethane It consists of three component reaction products of polymer component, polyester-based urethane polymer component and / or polyether-based urethane polymer component, and (C) diisocyanate, and these three components are reacted to produce a prepolymer. Further, those obtained by reacting a prepolymer with a chain extender such as diamine to extend the chain can be suitably used.
The polycarbonate-based urethane polymer component, the polyester-based urethane polymer component and / or the polyether-based urethane polymer component (B) may be used alone or in combination. The polyester-based urethane polymer component includes (1) adding a diamine compound to the polyester polyol component to urea a part of the urethane skeleton, (2) introducing a phenyl group into the polyester polyol component, (3) alcohol A polymer made by adding a diamine compound to a polyester polyol component having a polycarbonate component as the component to urea a part of the urethane skeleton can be used. The ratio of the acrylic polymer component of the acrylic-urethane block copolymer and the urethane polymer component may be adjusted as appropriate, but a mass ratio of 1/99 to 40/60 is preferable in terms of good adhesion performance. 40/60 to 60/40 is more preferable.

(Thermoplastic urethane resin)
A thermoplastic urethane resin can also be used as the urethane polymer component. The thermoplastic urethane resin is typically a resin obtained by reacting a diisocyanate, a high molecular polyol, and a low molecular polyfunctional active hydrogen compound such as a low molecular diol if necessary. Examples of the diisocyanate include 4,4′-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate, 1,5-naphthalene diisocyanate, n-isocyanate phenylsulfonyl isocyanate, m- or p-isocyanate phenylsulfonyl isocyanate, and the like. Aromatic diisocyanates; aliphatic diisocyanates such as 1,6-hexamethylene diisocyanate; alicyclic diisocyanates such as isophorone diisocyanate (IPDI), hydrogenated xylylene diisocyanate and hydrogenated diphenylmethane diisocyanate are used. Alternatively, multimers or adducts of these diisocyanates can also be used. These diisocyanates may be used alone or in combination of two or more.

Examples of the polymer polyol (herein, the polymer refers to a low molecular polyfunctional active hydrogen compound and includes a molecular weight of less than 10,000) include polycarbonate polyol, polyester polyol, polyether polyol, and the like. Or a mixture of two or more. In terms of weather resistance adhesion, polyester polyol is more preferable than polyether polyol, and polycarbonate polyol is more preferable.
Examples of the polyester polyol include a condensed polyester diol obtained by reacting a low molecular diol and a dicarboxylic acid, and a polylactone diol obtained by ring-opening polymerization of a lactone.

Here, as the dicarboxylic acid used, aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid, maleic acid and fumaric acid; aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, etc. However, it is used individually by 1 type or in mixture of 2 or more types. Moreover, (epsilon) -caprolactone etc. are used for the said lactone.
Specific examples of the polyester polyol include polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, polyneopentyl adipate, polyethylene butylene adipate, polybutylene hexabutylene adipate, polydiethylene adipate, poly (polytetramethylene ether) adipate, Examples thereof include polyethylene azate, polyethylene sebacate, polybutylene azate, polybutylene sebacate, polyhexamethylene carbonate diol, and the like. These may be used alone or in combination of two or more.

  Next, as a low molecular diol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, or a cyclic group Examples of low molecular weight diols having bis (hydroxymethyl) cyclohexane, m or p-xylene glycol, bis (hydroxymethyl) benzene, 1,4-bis (2-hydroxyethoxy) benzene, 4,4-bis (2- Hydroxyethoxy) -diphenylpropane (ethylene oxide adduct of bisphenol A) and the like are mentioned, and these are used alone or in combination of two or more.

《Titania》
In order to impart a white color for concealment to the primer layer, the primer layer is made to contain titania. As described above, since the problem of yellowing becomes particularly noticeable in a laminate exhibiting white, the laminate according to the present invention that does not yellow even in extremely severe environments exhibits a great effect when it is desired to have a white color. can do.
There are anatase type, brookite type and rutile type in titania. In the present invention, it is preferable that at least a part of the rutile type is contained from the viewpoint of concealment, and it is particularly preferable that all titania particles are rutile type. preferable. In addition, when using anatase type or brookite type titania, these types of titania have a strong photocatalytic action, and the resin component of the primer, the adjacent substrate, and the surface protective layer are highly decomposable. The rutile type is preferably contained in at least a part thereof.
The titania particle size is preferably in the range of 1 to 100 μm in aggregate particle size. When it is 1 μm or more, sufficient concealability is obtained, and when it is 100 μm or less, the dispersibility during coating is good. From the above viewpoint, the particle size of titania is more preferably in the range of 2 to 50 μm, particularly preferably in the range of 2 to 20 μm.

<Ultraviolet absorber>
The primer layer can contain an ultraviolet absorber as required. Preferred examples of the UV absorber include triazine UV absorbers, benzophenone UV absorbers, and cyanoacrylate UV absorbers.

  Examples of the triazine ultraviolet absorber include 2-4 [(2-hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2, described in the following chemical formula (1). 4-Dimethylphenyl) -1,3,5-triazine, 2-4 [(2-hydroxy-3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethyl Phenyl) -1,3,5-triazine and the like are preferable. Such a triazine-based ultraviolet absorber is commercially available as “Tinuvin 400 (trade name)” (manufactured by Ciba Japan Co., Ltd.). Tinuvin 400 is a mixture of the above triazine compounds and is a liquid containing 15% by weight of 1-methoxy-butanol.

Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxy-benzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-methoxy-benzophenone-5 Examples include 2-hydroxybenzophenone-based ultraviolet absorbers such as sulfonic acid.
Moreover, as a cyanoacrylate type ultraviolet absorber, 2-ethyl-hexyl-2-cyano-3,3-diphenyl acrylate, ethyl-2-cyano-3,3-diphenyl acrylate, octyl-2-cyano-3,3 -Diphenyl acrylate etc. are mentioned.

The content of the ultraviolet absorber in the laminate of the present invention is preferably in the range of 0.1 to 5 parts by mass with respect to 100 parts by mass of the resin component constituting the primer layer. When it is 0.1 parts by mass or more, an ultraviolet absorption effect is obtained, and when it is 5 parts by mass or less, there is no problem such as bleeding. From the above viewpoint, the content of the triazine-based ultraviolet absorber is more preferably in the range of 0.2 to 3 parts by mass, and particularly preferably in the range of 0.5 to 2 parts by mass.
When the primer layer is white, it is possible to reduce the addition amount of the ultraviolet absorber due to the concealing property of the white pigment. In this case, the content of the ultraviolet absorber is preferably 1 part by mass or less, and 0 to 1 mass. More preferably, it is a part. That is, even if the ultraviolet absorber is not contained, a sufficient ultraviolet absorption effect is ensured.

  In addition, the laminate of the present invention may contain an inorganic ultraviolet absorber, and examples thereof include zinc oxide, iron oxide, titanium oxide, cerium oxide having a particle size of 0.2 μm or less. The particle size of these particles is preferably 0.1 μm or less, and more preferably in the range of 8 to 30 nm.

<Method of laminating primer layers>
The primer layer dissolves the resin in a solvent, disperses titania powder used in the solution as necessary, and further adds various additives such as the UV absorber and light stabilizer that are added as necessary. The coating composition is used to form. That is, these compositions are formed on a substrate by drying and curing as necessary. More specifically, the coating composition is applied and dried and cured by a method such as gravure roll coating or roll coating. The coating amount of the coating composition for forming the primer layer is preferably in the range of 0.5 to 20 g / m ² (when dried), and preferably in the range of 1 to 10 g / m ² (when dried). More preferably.
About the thickness of a primer layer, the range of 0.5-20 micrometers is preferable, and the range of 1-10 micrometers is more preferable.

[Surface protective layer]
The surface protective layer in the laminate of the present invention is obtained by crosslinking and curing an ionizing radiation curable resin composition. The ionizing radiation curable resin can be appropriately selected from a polymerizable monomer and a polymerizable oligomer or prepolymer conventionally used as an ionizing radiation curable resin, but from the viewpoint of obtaining good curing characteristics. It is preferable that it is difficult to bleed out, has a coating property even if it is about 95 to 100% as a solid content, and does not easily cause curing shrinkage when cured. Representative examples of such ionizing radiation curable resins are described below. “(Meth) acrylate” means “acrylate or methacrylate”.

  As the polymerizable monomer, a (meth) acrylate monomer having a radically polymerizable unsaturated group in the molecule is suitable, and in particular, a polyfunctionality having two or more ethylenically unsaturated bonds in the molecule ( (Meth) acrylate is preferred, and one kind may be used alone, or two or more kinds may be used in combination. As a functional group number, 2-8 are preferable, 2-6 are more preferable, and 3-4 are more preferable.

  In the present invention, together with the polyfunctional (meth) acrylate, for the purpose of adjusting the viscosity, monofunctional (meth) acrylates such as methyl (meth) acrylate are within a range that does not impair the purpose of the present invention. It can be used together as appropriate. A monofunctional (meth) acrylate may be used individually by 1 type, and may be used in combination of 2 or more type.

  Next, as the polymerizable oligomer, an oligomer having a radically polymerizable unsaturated group in the molecule, for example, epoxy (meth) acrylate, urethane (meth) acrylate, polyester (meth) acrylate, polyether (meth) Preferred examples include acrylate oligomers. Among these oligomers, polyfunctional polymerizable oligomers are preferable, and the number of functional groups is preferably 2 to 16, more preferably 2 to 8, and still more preferably 2 to 6.

  Furthermore, other polymerizable oligomers include polybutadiene (meth) acrylate oligomers with high hydrophobicity that have (meth) acrylate groups in the side chain of polybutadiene oligomers, and silicone (meth) acrylate oligomers that have polysiloxane bonds in the main chain. In a molecule such as an aminoplast resin (meth) acrylate oligomer modified with an aminoplast resin having many reactive groups in a small molecule, or a novolak type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc. There are oligomers having a cationic polymerizable functional group. These polymerizable oligomers may be used individually by 1 type, and may be used in combination of 2 or more type.

  When an ultraviolet curable resin is used as the ionizing radiation curable resin, it is desirable to add about 0.1 to 5 parts by mass of a photopolymerization initiator with respect to 100 parts by mass of the ultraviolet curable resin. The initiator for photopolymerization can be appropriately selected from those conventionally used and is not particularly limited.

  In the present invention, it is preferable to use an electron beam curable resin as the ionizing radiation curable resin. This is because the ionizing radiation curable resin composition in the present invention contains an ultraviolet absorber, and in the case of irradiation with ultraviolet rays, the ultraviolet irradiation amount may be insufficient. Although preparation may be required, in the case of electron beam irradiation, such preparation is unnecessary, and stable curing characteristics can be obtained efficiently.

  Further, as described above, any one of the primer layer and the surface protective layer needs to be at least white or transparent. When the surface protective layer is white, the above-described titania may be used.

  For surface protective layer, additives include UV absorber, antiwear improver, polymerization inhibitor, crosslinking agent, infrared absorber, antistatic agent, adhesion improver, leveling agent, thixotropic agent, coupling An agent, a plasticizer, an antifoaming agent, a filler, an antiblocking agent, a lubricant, a solvent and the like can be added.

As an ultraviolet absorber, the same thing as what is contained in a primer layer can be used. Its content is also the same as that of the primer layer.
Examples of the wear resistance improver include spherical particles such as α-alumina, silica, kaolinite, iron oxide, diamond, and silicon carbide. Examples of the particle shape include a sphere, an ellipsoid, a polyhedron, a scale shape, and the like. Although there is no particular limitation, a spherical shape is preferable. Organic materials include synthetic resin beads such as cross-linked acrylic resin and polycarbonate resin. The particle size is usually about 30 to 200% of the film thickness. Among these, spherical α-alumina is particularly preferable because it has high hardness and a large effect on improving wear resistance, and it is relatively easy to obtain spherical particles.
Examples of the polymerization inhibitor include hydroquinone, p-benzoquinone, hydroquinone monomethyl ether, pyrogallol, and t-butylcatechol. Examples of the crosslinking agent include a polyisocyanate compound, an epoxy compound, a metal chelate compound, an aziridine compound, and an oxazoline compound. Used.
As the infrared absorber, for example, a dithiol metal complex, a phthalocyanine compound, a diimmonium compound, or the like is used.
As the filler, for example, barium sulfate, talc, clay, calcium carbonate, aluminum hydroxide and the like are used.
As the anti-blocking agent or lubricant, wax components such as polyethylene wax and silica are preferably used.

In the present invention, the polymerizable monomer and polymerizable oligomer, which are the electron beam curing components, and various additives are homogeneously mixed at predetermined ratios to prepare a coating liquid comprising an electron beam curable resin composition. To do. The viscosity of the coating solution is not particularly limited as long as it is a viscosity capable of forming an uncured resin layer on the surface of the substrate by a coating method described later.
In the present invention, the coating liquid prepared in this way is applied to the surface of the primer layer so that the thickness after curing is 1 to 20 μm, gravure coating, bar coating, roll coating, reverse roll coating, Coating is performed by a known method such as comma coating, preferably gravure coating, to form an uncured resin layer. A surface protective layer having a desired function is obtained when the thickness after curing is 1 μm or more. The thickness of the surface protective layer after curing is preferably about 2 to 20 μm.

The uncured resin layer formed as described above is irradiated with an electron beam to cure the uncured resin layer. The acceleration voltage can be appropriately selected according to the resin to be used and the thickness of the layer, but it is preferable to cure the uncured resin layer at an acceleration voltage of about 70 to 300 kV.
The irradiation dose is preferably such that the crosslinking density of the resin layer is saturated, and is usually selected in the range of 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 50 kGy (1 to 10 Mrad).
Further, the electron beam source is not particularly limited. For example, various electron beam accelerators such as a cockroft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type. Can be used.

(Laminate)
In the laminate of the present invention, another layer may be formed on the side opposite to the surface protective layer formed (the back side with respect to the surface protective layer), or a film may be attached.
The film used here is premised on having a role as a support, and the strength, rigidity, water vapor barrier property, weather resistance, heat resistance, hydrolysis resistance, light reflectivity, depending on the purpose of use. In addition, it is necessary to select appropriately according to the case where functions such as design properties and adhesion to the material on the side opposite to the surface protective layer are required.

  As a film having excellent strength, for example, it has excellent mechanical, chemical, or physical strength, and has insulation, weather resistance, heat resistance, water resistance, light resistance, chemical resistance, moisture resistance, and antifouling. Excellent in lightness, light reflectivity, light diffusivity, design, and other characteristics, minimizing performance degradation, etc. for long-term use, rich in durability, excellent in protection functionality and light In addition, it has advantages such as excellent processability and easy handling, and further, one or more kinds of resins having low cost and high safety can be used. Examples of such films include polyethylene resin films, polypropylene resin films, cyclic polyolefin resin films, polystyrene resin films, acrylonitrile-styrene copolymer (AS resin) films, and acrylonitrile-butadiene-styrene copolymers. (ABS resin) film, polyvinyl chloride resin film, fluorine resin film, poly (meth) acrylic resin film, polycarbonate resin film, polyester resin film such as polyethylene terephthalate or polyethylene naphthalate, various nylons, etc. Polyamide resin film, polyimide resin film, polyamideimide resin film, polyarylphthalate resin film, silicon resin film, polysulfide Emissions-based resin film, a polyphenylene sulfide-based resin films, polyether sulfone resin films, polyurethane resin film, acetal resin film, a cellulose resin film, a resin film of miscellaneous other may preferably be mentioned.

  When the polypropylene resin is used, either a stretched film or a non-stretched film or sheet can be used. When hydrolysis resistance is required, the polyester resin is an oligomer. A hydrolysis-resistant polyester resin having a content of 0.1 to 0.6% by mass and a carboxyl end group amount of about 3 to 15 equivalents / ton can also be used.

  In the present invention, among the above resins, a polyethylene resin, a polypropylene resin, a cyclic polyolefin resin, or a polyester resin is preferable, and a high density polyethylene resin, a polypropylene resin, a cyclic polyolefin resin, or a polyester resin is preferable. Is preferred.

When water vapor barrier properties are required, a water vapor barrier film in which a metal or metal oxide deposit is laminated on at least one layer of one or two or more thermoplastic resin layers, or aluminum A water vapor barrier substrate made of foil or the like can be laminated.
In addition, when adhesion with a substance on the side opposite to the surface protective layer is formed, particularly when adhering by thermocompression bonding, an ethylene-vinyl acetate copolymer resin film, a fluororesin film, A polyethylene film, a polypropylene film, etc. are mentioned preferably, These can be used individually or in combination.

  The thickness of the film is preferably 100 to 500 μm, more preferably 250 to 400 μm in terms of the total thickness when laminated. This is because the mechanical strength of the laminate and the insulating properties when used for electrical member applications are required.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by this example. In addition, the evaluation method in this invention was performed with the following method.
《Evaluation of yellowing》
The laminated body obtained in each Example and Comparative Example was subjected to a heat and humidity resistance test for 2000 hours under the conditions of a temperature of 85 ° C. and a relative humidity of 85%, and the difference in YI value (ΔYI value) before and after the test was determined. It measured based on JIS-K-7501. A spectral colorimeter “SD-5000 (model number)” (manufactured by Nippon Denshoku Industries Co., Ltd.) was used for measurement of the ΔYI value. The evaluation criteria are as follows.
○: ΔYI value is less than 3 Δ; ΔYI value is 3 or more and less than 5 ×; ΔYI value is 5 or more << Evaluation of weather resistance >>
About the laminated body obtained by each Example and the comparative example, the weather resistance test by the following conditions was done, and the change of the external appearance of the laminated body before and after that was evaluated on the following reference | standard.
○: No change in appearance was observed. Δ: Fine cracks and detachment were confirmed on the surface, but there was no problem in practical use. ×: Fine cracks and detachment were observed on the surface (weather resistance) test)
Testing machine: Metal weather testing machine ("KW-R5TP (model number)", manufactured by Daipura Wintes Co., Ltd.)
Conditions: A cycle test was repeated for 20 cycles, with the following 24 hours as one cycle. A KF-1 filter was used as the filter.
Illuminance: 60 mW / cm ² , Black panel temperature: 63 ° C., 20 hours at 50% relative humidity Illuminance: 0 mW / cm ² , Black panel temperature: 30 ° C., 4 hours at 98% relative humidity Sprinkling for 10 seconds when switching between light and dark

Example 1
One side of a hydrolysis-resistant biaxially stretched polyester film (“Lumirror X10S (trade name)”, manufactured by Toray Industries, Inc.) having a thickness of 50 μm was subjected to corona treatment. On the corona-treated surface, 100 parts by mass of a two-part curable resin comprising a polyurethane resin, an acrylic resin, and an isocyanate compound, and 100 parts by mass of a white pigment (rutile titanium oxide) having an average particle size of about 10 μm, a triazine ultraviolet absorber ("Tinubin 400 (trade name)", manufactured by Ciba Japan Co., Ltd.) 1 part by mass, triazine-based ultraviolet absorber ("Tinuvin 479 (trade name)", manufactured by Ciba Japan Co., Ltd.) 1 part by mass, hindered amine light 2 parts by mass of a stabilizer (“Tinuvin 123 (trade name)”, manufactured by Ciba Japan Co., Ltd.), and a hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group (“Irganox 1010 (product) Name) ”, manufactured by Ciba Japan Co., Ltd.) The two-component curable white primer coating solution consisting of 1 part by mass will have a thickness of 3 μm after drying. As described above, coating and drying were performed to form a white primer layer.
On the primer layer side, as an ionizing radiation curable resin composition, 20 parts by mass of silica particles having an average particle diameter of 8 μm and polyethylene wax fine powder (average particle diameter: 5 μm, melting point: 165 with respect to 100 parts by mass of urethane acrylate resin. 5 parts by mass, 1 part by mass of a triazine-based ultraviolet absorber (“Tinuvin 400 (trade name)”, manufactured by Ciba Japan Co., Ltd.), a hindered amine-based light stabilizer (“Tinuvin 123 (trade name)”, Ciba Japan Co., Ltd.) 3 parts by mass, hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group (“Irganox 1010 (trade name)”, Ciba Japan Co., Ltd.) 1 part by weight and acetic acid A coating solution consisting of 200 parts by mass of ethyl was applied so that the thickness after crosslinking and curing was 5 μm, and dried.
Next, an oxygen concentration of 100 ppm or less is applied to the layer formed of the ionizing radiation curable resin composition formed by coating using an electron beam irradiation apparatus (“Electro Curtain EC250 / 150 / 180L (model)”, manufactured by Iwasaki Electric Co., Ltd.). In a nitrogen gas atmosphere, an electron beam was irradiated and crosslinked and cured under the conditions of an accelerating voltage of 165 kV, an absorbed dose of 50 kGy, and a conveyance speed of 10 m / min to form a surface protective layer.
A 12 μm-thick polyester film (“Techbarrier (registered trademark),” on which a silicon oxide vapor-deposited film is sequentially formed on the hydrolysis-resistant biaxially stretched polyester film on the side facing the surface protective layer. The same applies hereinafter) LX (trade name) ”, manufactured by Mitsubishi Plastics Co., Ltd., disposed so that the deposited film surface is on the hydrolysis-resistant biaxially stretched polyester film side), a transparent biaxially stretched polyester film having a thickness of 100 μm, A white high-density polyethylene film having a thickness of 120 μm was laminated by laminating and laminating by a dry laminating method using a polyurethane two-component adhesive so that the thickness after coating and drying was 5 μm. The laminate was prepared by curing in an oven for 1 week. The results evaluated by the above method are shown in Table 1.

Example 2
In Example 1, a laminate was produced in the same manner as in Example 1 except that the ionizing radiation curable resin composition was not mixed with a hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group. . The results evaluated by the above method are shown in Table 1.

Example 3
In Example 1, the laminate was prepared in the same manner as in Example 1 except that the hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group was not added to the two-component curable white primer coating solution. Produced. The results evaluated by the above method are shown in Table 1.

Example 4
In Example 1, instead of the hindered phenol-based antioxidant having — (CH ₂ ) ₂ —COO— group used in the two-component curable white primer coating solution and the ionizing radiation curable resin composition, — ( A laminate in the same manner as in Example 1 except that a hindered phenol-based antioxidant having a CH ₂ ) ₂ —COO— group (“Irganox 1076 (trade name)”, manufactured by Ciba Japan Co., Ltd.) was used. Was made. The results evaluated by the above method are shown in Table 1.

Example 5
In Example 1, in place of the hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group used in the two-component curable white primer coating solution and the ionizing radiation curable resin composition, a sulfur-based one is used. A laminate was produced in the same manner as in Example 1 except that an antioxidant (“Irganox 1726 (trade name)”, manufactured by Ciba Japan Co., Ltd.) was used. The results evaluated by the above method are shown in Table 1.

Example 6
In Example 1, in place of the hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group used in the two-component curable white primer coating solution and the ionizing radiation curable resin composition, a sulfur-based one is used. A laminate was produced in the same manner as in Example 1 except that an antioxidant (“ADK STAB AO503A (trade name)”, manufactured by ADEKA Corporation) was used. The results evaluated by the above method are shown in Table 1.

Example 7
In Example 6, a laminate was produced in the same manner as in Example 6 except that no sulfur-based antioxidant was added to the ionizing radiation curable resin composition. The results evaluated by the above method are shown in Table 1.

Example 8
In Example 6, a laminate was produced in the same manner as in Example 6 except that no sulfur-based antioxidant was added to the two-component curable white primer coating solution. The results evaluated by the above method are shown in Table 1.

Example 9
In Example 6, a laminate was produced in the same manner as in Example 6 except that the white pigment used in the two-component curable white primer coating solution was changed to 3 parts by mass of silica particles (average particle size: 8 μm). The results evaluated by the above method are shown in Table 1.

Example 10
In Example 6, a laminate was produced in the same manner as in Example 6 except that the hindered amine light stabilizer was not used in the two-component curable white primer coating solution. The results evaluated by the above method are shown in Table 1.

Comparative Example 1
In Example 1, except that the hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group was not used in the two-component curable white primer coating solution and the ionizing radiation curable resin composition. In the same manner as in No. 1, a laminate was obtained. The results evaluated by the above method are shown in Table 1.

Comparative Example 2
In Example 1, a hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group used in a two-component curable white primer coating solution and an ionizing radiation curable resin composition is represented by — (CH ₂ ) A laminate was obtained in the same manner as in Example 1 except that a hindered phenol antioxidant having no ₂ -COO- group ("Irganox 1330 (trade name)", Ciba Japan Co., Ltd.) was used. It was. The results evaluated by the above method are shown in Table 1.

  According to the present invention, it is possible to provide a laminate having excellent weather resistance, which does not yellow, and does not crack even under extremely severe environments. Therefore, members and parts exposed to sunlight, such as outdoor structures. It is effective for applications that protect

Claims (3)

A laminate comprising at least a primer layer and a surface protective layer on a substrate, wherein the primer layer includes rutile-type titania and exhibits white, and the surface protective layer exhibits white or transparent, The surface protective layer is formed by crosslinking and curing an ionizing radiation curable resin fat composition containing a hindered amine light stabilizer and a urethane (meth) acrylate polymerizable oligomer as an ionizing radiation curable resin, the primer layer and / or the primer layer The surface protective layer contains at least one selected from a hindered phenol-based antioxidant having a — (CH ₂ ) ₂ —COO— group and a sulfur-based antioxidant, and the resin constituting the primer layer is a two-component curing A laminate that is a polyurethane resin that is a type selected from a type urethane resin, an acrylic-urethane block copolymer, and a thermoplastic urethane resin.   The laminate according to claim 1, wherein the primer layer further contains a hindered amine light stabilizer. The laminate according to claim 1 or 2 , wherein the content of the light stabilizer in the surface protective layer is 0.1 to 10 parts by mass with respect to 100 parts by mass of the ionizing radiation curable resin.