JP5857495B2 - Transparent resin sheet - Google Patents

Description

  The present invention relates to a transparent resin sheet to be bonded to the surface of a member such as a base material using natural wood, plywood, laminated wood, aluminum material, steel plate material alone or in combination, and particularly on the surface of furniture such as window frames and furniture. The present invention relates to a transparent resin sheet that is bonded to improve weather resistance and the like.

  Joinery and furniture assembled from paper or sheets printed with patterns such as wood grain and the like are bonded to the surface of a wooden member, and are well received by the market because they are highly durable, stable in design, and inexpensive. I came. Of course, those using conventional solid wood and veneer are also popular in the market due to their good design. However, solid materials and veneer materials have a problem in terms of durability, and colors may fade or become rotted over time. Therefore, it has not been encouraged to use it in places where sunlight shines, not only for exterior materials but also for interior materials.

  In order to improve such a situation, an elastomer component is introduced into acrylic to give flexibility, and further, a film formed into a sheet shape containing various weathering agents is applied to the surface layer of natural wood or veneer material. The thing which gave the weather resistance performance by pasting together is proposed, and some commercialization is also made | formed.

  However, since acrylic resins are not highly resistant to various organic solvents and are not highly resistant to some pollutants, care must be taken when handling them. Further, if the elastomer component is contained in a large amount and the stiffness is lowered, the high weather resistance that is the original characteristic of the acrylic resin cannot be sufficiently exhibited. On the other hand, if the elastomer component is decreased, flexibility is lost, and there is a possibility that cracks and floats are likely to occur when pasting (wrapping) on a substrate. Above all, since the acrylic sheet is expensive, an alternative sheet material is desired from the viewpoint of economy.

JP 2001-058371 A

  The present invention has been made in order to solve the above-mentioned problems from such a background, and the problem is that it is used by being bonded to the surface layer of a solid material or a veneer material, and has chemical resistance and design properties. It is to provide a transparent resin sheet that has both necessary and sufficient transparency, weather resistance, and lapping ability, and that does not greatly impair the texture of a solid material or a veneer.

The present invention solves the above-mentioned problem, that is, the invention according to claim 1 is a transparent resin sheet comprising at least one resin layer used by being bonded to the surface of a member.
The resin layer contains a polypropylene resin as a main component, contains a resin component obtained by copolymerization of ethylene or α-olefin component based on propylene, and contains an ultraviolet absorber and a light stabilizer in at least one of the resin layers. And the thickness of the resin layer is 50 to 300 μm,
A non-thermoplastic resin layer containing an ultraviolet absorber and a light stabilizer is laminated on the surface of the resin layer, the non-thermoplastic resin layer contains a true spherical filler, and a part of the true spherical filler Is a transparent resin sheet characterized in that the latent heat of fusion in the differential scanning calorimetry of the transparent resin sheet is in the range of 10 to 100 J / g.

Invention of the second aspect, wherein the spherical filler has a transparent resin sheet according to claim 1, characterized in that it consists of an inorganic glass.

The invention described in claim 3 is the transparent resin sheet according to any one of claims 1 and 2 , wherein a pattern layer is provided on the back surface of the resin layer.

  According to the first aspect of the present invention, there is provided a transparent resin sheet having chemical resistance, stain resistance, and design properties, and having necessary and sufficient transparency, weather resistance, and lapping ability. It becomes possible. This is because by using polypropylene resin as a main component, the solvent resistance and stain resistance, which were the drawbacks of acrylic resins, can be greatly improved. However, a simple polypropylene resin does not provide sufficient performance in terms of transparency, flexibility, weather resistance, etc., but contains a resin component obtained by copolymerizing ethylene or an α-olefin component based on propylene. Thus, crystallization of the polypropylene resin can be suppressed, and as a result, transparency and flexibility can be obtained at the same time. In addition, when the ultraviolet absorber and the light stabilizer are contained in at least one layer, the performance as an ultraviolet transparent resin sheet can be imparted, and the thickness within the range of 50 to 300 μm is sufficient. It becomes possible to have a level of flexibility that does not impair lapping suitability while having weather resistance performance.

  For resin components in which ethylene or α-olefin components are copolymerized with propylene, various types of materials have been proposed by various manufacturers, but the transparent resin sheet of the present invention is used over a long period of time. For this reason, it is desirable that transparency and other performance be maintained for a long period of time. From this point of view, the use of a metallocene catalyst at the time of polymerization is desirable because it has advantages such as a reduction in low molecular weight components. Moreover, the component to be copolymerized is not limited to one type, and a plurality of types of monomers may be used in combination. In addition, it is possible to impart flexibility even by containing a resin obtained by copolymerizing an α-olefin based on ethylene. However, since compatibility with polypropylene resin is difficult, transparency can be ensured. Because it is not possible, it is not suitable.

  A suitable content of a resin component obtained by copolymerizing propylene with an ethylene or α-olefin component is appropriately set such that a latent heat of fusion ΔH in DSC (differential scanning calorimetry) is within a range of 10 to 100 J / g. The The resin component obtained by copolymerizing propylene with ethylene or α-olefin component tends to decrease the value of the latent heat of fusion as its content increases. However, when the latent heat of fusion exceeds 100 J / g, it is sufficiently transparent. If the latent heat of fusion is less than 10 J / g, the hardness of the surface cannot be maintained, the surface is easily scratched, and the sheet is stretched by the tension during wrapping. It is very difficult to wrap with good design. Here, the latent heat of fusion is the total amount of heat necessary to completely melt the crystal, and can be obtained by a differential scanning calorimeter.

The present invention by the inventors of claim 1, it is possible to further obtain the weather resistance of the high level. The thermoplastic resin is two-dimensionally polymerized, whereas the non-thermoplastic resin layer is three-dimensionally cross-linked. This is because there is an effect on suppression. The method for crosslinking is not particularly limited, but methods such as isocyanate crosslinking, ultraviolet crosslinking, and electron beam crosslinking are preferably used. Further, before the crosslinking is carried out by these methods, it may be previously oligomerized in a polymerization vessel.

According to the invention of the first aspect of the present invention, since a part of the filler exposed on the outermost layer gives an appropriate feeling of unevenness, it is possible to give a good touch feeling, and a texture closer to a real tree. Therefore, even when the transparent resin sheet of the present invention is bonded to the surface layer of a solid material or a veneer by overlaminating, the texture of the solid material or the veneer can be maintained. Moreover, since it is a spherical shape, there is little influence of light deflection etc., and transparency can be ensured.

According to the second aspect of the present invention, by selecting inorganic glass as a filler, deterioration with time can be suppressed as compared with the case of selecting an organic material.

According to the third aspect of the present invention, it is possible to further enhance the texture of the building member by making the design pattern layer visible through the resin layer, and it is possible to improve the texture of the building member, as well as a solid material, a veneer material, etc. There is also an effect that it is possible to suppress the variation of the design that tends to occur in the natural material.

It is explanatory drawing which shows the structure of the cross section of one Example of the transparent resin sheet of this invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows a cross-sectional structure of an embodiment of the transparent resin sheet of the present invention. It comprises at least one or more resin layers 1 constituting the transparent resin sheet of the present invention, a non-thermoplastic resin 2 appropriately provided on the front surface side, and a pattern layer 3 appropriately provided on the back surface side.

  As the resin layer 1 in the present invention, a layer containing a resin component obtained by copolymerizing an ethylene or α-olefin component based on propylene and containing propylene as a main component is used. Further, a mixture obtained by melt-kneading a mixture containing an ultraviolet absorber and a light stabilizer using a twin screw extruder or the like is used. As polypropylene, homopolypropylene obtained by polymerizing propylene alone, random polypropylene obtained by random copolymerization of about 0.01 to 10 mol% using ethylene or butene as a comonomer, and also about 0.1 to 50 mol%, Although it is divided roughly into block polypropylene polymerized so that a comonomer becomes a block, it is not suitable to use block polypropylene for resin for transparent resin sheets of the present invention from a viewpoint of ensuring transparency. Both homopolypropylene and random polypropylene can be used for the transparent resin sheet of the present invention. However, if you want to place heavy weight due to flexibility and transparency, use random polypropylene, and place heavy weight due to scratch resistance and heat resistance. In some cases, it is better to use homopolypropylene.

  Examples of the resin component obtained by copolymerizing ethylene or α-olefin component based on propylene include “NOTIO” manufactured by Mitsui Chemicals, “Vistamax” manufactured by ExxonMobil, and “Prime TPO random type manufactured by Prime Polymer Co., Ltd.” ”,“ Zeras ”manufactured by Mitsubishi Chemical Corporation,“ Cataloy ”manufactured by Sun Allomer Co., Ltd., but metallocene catalysts such as“ Notio ”and“ Vistamax ”are considered from the viewpoint of eliminating the influence of low molecular weight components as much as possible. It is more preferable to use a resin polymerized by the above method. There are no particular restrictions on the amount of addition, but in view of the type and rigidity of the main component polypropylene, the type and rigidity of the resin component obtained by copolymerizing ethylene or α-olefin component based on propylene, etc. What is necessary is just to contain suitably so that latent heat (DELTA) H may be 10-100 J / g.

  The ultraviolet absorber and light stabilizer contained in at least one resin layer 1 are also indispensable materials for obtaining desired performance in the present invention. UV absorbers can be broadly classified into organic and inorganic types, and the characteristics of organic UV absorbers are that they have the function of converting UV light energy into heat energy that is harmless to plastic materials. It is. On the other hand, the inorganic type often exhibits its performance by reflecting the ultraviolet ray as it is, so the name of the ultraviolet ray-cutting material is more appropriate. Organic ultraviolet absorbers include benzotriazoles, benzophenones, benzoates, and triazines. Among them, various types of ultraviolet absorbers have been promoted by various companies due to differences in fine molecular structures. In selecting an ultraviolet absorber, a suitable one may be selected from the viewpoint of absorption wavelength range, absorption strength, material stability, affinity with the contained material, and the like, as in the present invention, a polypropylene resin. When the main material is benzotriazole, it is preferably selected.

  The light stabilizer has a capability of capturing and detoxifying free radicals excited by ultraviolet rays or heat, and is also called a radical scavenger. As the type, mainly hindered amines are preferably used.

  In addition, although the said ultraviolet absorber and light stabilizer should just be contained in one or more layers in a transparent resin sheet, the highest effect will be acquired when it contains in the outermost layer. Of course, it is still more desirable to contain for two or more layers.

  The pattern layer 3 is not provided with concealability but is provided as appropriate in order to further improve the design while utilizing the texture of the underlying base material. The material is not particularly limited, but based on a polyester or acrylic resin, colorants such as dyes or pigments, extender pigments, pearls, etc. are added, and plasticizers, stabilizers, waxes, greases, and drys as necessary. An agent, a curing agent, a thickener, a dispersant, a filler and the like which are arbitrarily added and kneaded sufficiently with a solvent, a diluent and the like are preferably used. The pattern pattern layer 3 may be laminated by various printing methods or coating methods, but the gravure printing method is preferred. Moreover, in order to improve the adhesive force of the pattern pattern layer 3, a lamination | stacking of a primer coat layer (not shown) is suitably used between the resin layer 1 and the pattern pattern layer 3 as needed.

  Examples of the method for producing the resin layer 1 include a T-die extrusion method, an inflation method, a calendar method, and the like. However, the resin layer 1 may be formed of a multi-layer laminate in order to provide functionality. In that case, a T-die extrusion method or an inflation method is preferably used. Further, when importance is attached to the thickness accuracy, the T-die extrusion method or the calendar method is suitable, and when it is desired to satisfy both of them simultaneously, the T-die extrusion method is preferably used.

  In the present invention, the non-thermoplastic resin layer 2 provided as appropriate reacts, as a material, specifically with a prepolymer in which a hydroxyl group is introduced into an acrylic resin or an ester resin, and a curing agent having a separately prepared isocyanate group. It is good to make it harden | cure by making a urethane reaction product generate | occur | produce in resin. As the isocyanate component, an aromatic component may be used if importance is attached to immediate curing, and an aliphatic component may be used if importance is placed on ultraviolet resistance. In addition, when it is desired to impart flexibility to the non-thermoplastic resin layer 2, a method of modifying the urethane from a prepolymer state is also preferably used.

  As a method of curing the non-thermoplastic resin layer 2, in addition to a method of reacting with isocyanate (isocyanate curing method), a method of irradiating ultraviolet rays after adding a photopolymerization initiator (ultraviolet curing method), or irradiating with an electron beam A method (electron beam curing method) or the like may be used. A plurality of these curing methods may be combined.

  The lamination method of the non-thermoplastic resin layer 2 may be a known technique and is not limited in any way, but a gravure coating method is generally used. The thickness is preferably about 3 to 50 μm. However, in the case of the gravure coating method, the film thickness that can be coated at one time is about several μm. If the thickness is more than that, there may be a problem such as unevenness on the coating surface. In that case, a method of coating repeatedly to a desired thickness in a plurality of times is preferably used.

  As the thickness of the non-thermoplastic resin layer 2 is increased, the scratch resistance increases and the result of the pencil hardness test tends to be improved. However, when the lapping is performed, the hard coat surface protective layer 5 It also has the problem of easily causing cracks and cracks. From these balances, the appropriate thickness is preferably in the range of 3 to 50 μm.

  In order to increase the adhesion of the non-thermoplastic resin layer 2, it is also necessary to introduce a polar group at the lamination interface by a known technique such as corona treatment, and in particular, it is basically a nonpolar resin. When a transparent olefin resin is used, polar group introduction by corona treatment or the like is preferably performed.

  The non-thermoplastic resin layer 2 preferably contains a true spherical filler. As the performance of the true spherical filler, an effect of improving the tactile sensation of the surface can be expected. In particular, when a part of the true spherical filler is exposed on the surface or when the true spherical shape is raised on the surface, a better tactile sensation can be obtained. The material of the true spherical filler may be either organic or inorganic, but from the viewpoint of durability, an inorganic material is preferable in view of resistance to ultraviolet rays and oxidation, and scratch resistance. In consideration of adhesion and economy, inorganic glass is preferably used.

  The transparent resin sheet of the present invention may be provided with a primer coat (not shown) as necessary in order to improve the adhesion to the member direction. As for the material of the primer, an acrylic or polyester-based material is suitably used as in the non-thermoplastic resin layer 2 and the pattern layer 3. Also, a known method may be used as a method for laminating the primer layer.

  The transparent resin sheet created in this way is bonded to the surface layer of a solid material or veneer material, so that it has chemical resistance, stain resistance, and design properties, and sufficient and sufficient transparency, weather resistance, and wrapping suitability. In addition, the texture of the solid material and the veneer material is not greatly impaired.

  Random polypropylene resin having an MFR under a temperature environment of 230 ° C. of 24, a melting point of differential scanning calorimetry of 134 ° C., and ethylene content of 4.3% in monomer units as measured by the method defined in JIS K7210 Prime Polypropylene Y-2045GP "(manufactured by Prime Polymer Co., Ltd.) was prepared in an amount of 80% by weight. Further, as a propylene elastomer having an MFR of 6 under a 230 ° C temperature environment and a melting point of 140 ° C of differential scanning calorimetry, “PN-3560” (Mitsui Chemicals) is 19% by weight, “Irganox 1010” (BASF Japan Ltd.) is 0.1% by weight as a phenolic antioxidant, and “Ilfugaphos 168 is used as a phosphorus processing stabilizer. "(BASF Japan Co., Ltd.) 0.15% by weight, hindered amine-based Koyasu “Kimasorb 944” (manufactured by BASF Japan Ltd.) is added by 0.3% by weight as a fixed agent, and “Tinuvin 326” (manufactured by BASF Japan Ltd.) is added by 0.45% by weight as a benzotriazole-based ultraviolet absorber, After melt-kneading at an extrusion temperature of 230 ° C. using a single screw extruder, a resin layer 1 was prepared by melt extrusion from a T-type die with an extrusion thickness of 200 μm. Using a differential scanning calorimeter DSC 6220 (manufactured by Seiko Instruments Inc.), this sheet was heated from 0 ° C. to 300 ° C. at a rate of 10 ° C. per minute and the latent heat of fusion was measured to be 55 J / g.

  Both surfaces of the obtained resin layer 1 are subjected to corona treatment, and on the surface side, 5 parts of hexamethylene diisocyanate is added to 100 parts by weight of a polyester primer coating agent “V324” (manufactured by Toyo Ink Manufacturing Co., Ltd.). In addition, using a gravure coating method, an average thickness of 1.5 μm after solvent evaporation and drying was applied using a gravure coating method, and a non-thermoplastic resin layer 2 was added. A transparent resin sheet was prepared.

  Example 1 "Lamistor" (manufactured by Toyo Ink Manufacturing Co., Ltd.), a pattern ink mainly composed of a polyester material, was added with 5 parts by weight of hexamethylene diisocyanate and an ethyl acetate solution and stirred well. The pattern layer 3 was provided on the back side of the resin layer 1 obtained in the same manner as described above by laminating and coating with a gravure printing method.

  A coating agent “UC Clear” containing an acrylic material as a main raw material, a benzotriazole-based UV absorber and a hindered amine-based light stabilizer on the surface side of the resin layer 1 provided with the pattern layer 3 on the back side. (DIC Graphics Co., Ltd.), 5 parts by weight of hexamethylene diisocyanate and an ethyl acetate solution are added and stirred well, and the coating thickness after solvent evaporation and drying is 6 μm using the gravure coating method. Thus, a non-thermoplastic resin layer 2 was provided to produce a transparent resin sheet.

  Using a cross-linked polybutyl methacrylate particle “Sekisui Tech Polymer BM30X-12” (manufactured by Sekisui Plastics Co., Ltd.) having an average particle size of 12 μm as a true spherical filler, the solid of the “UC Clear” (manufactured by DIC Graphics Co., Ltd.) A transparent resin sheet was produced using the same production method as in Example 2 except that it was blended and stirred at a ratio of 12% by weight to the minute.

  Example 2 is the same as Example 2 except that glass beads “Unibeads SPL-30” (manufactured by Unitika Co., Ltd.) having a mean particle size of 30 μm as a true spherical filler were mixed and stirred at a ratio of 12% by weight with respect to the solid content of UC clear. A transparent resin sheet was produced using the same production method.

<Comparative Example 1>
The resin layer 1 is composed of a polymethyl methacrylate resin as a main component and a 50 μm-thick film “Acryprene HBS027” (manufactured by Mitsubishi Rayon Co., Ltd.) containing a hindered amine light stabilizer and a benzotriazole ultraviolet absorber. A transparent resin sheet was prepared using the same method as in Example 1.

<Comparative Example 2>
A transparent resin sheet was produced using the same method as in Example 1 except that the thickness of the resin layer 1 was 40 μm.

<Comparative Example 3>
A transparent resin sheet was produced using the same method as in Example 1 except that the thickness of the resin layer 1 was 350 μm.

<Comparative Example 4>
A transparent resin sheet was produced using the same method as in Example 1 except that the hindered amine light stabilizer was not added.

<Comparative Example 5>
A transparent resin sheet was prepared in the same manner as in Example 1 except that the benzotriazole ultraviolet absorber was not added.

<Comparative Example 6>
“Notio PN-3560” (manufactured by Mitsui Chemicals, Inc.) is reduced to 5% by weight, and instead of “Y-2045GP”, MFR under a temperature environment of 230 ° C. measured by the method defined in JIS K7210 is 18. High melting point homopolypropylene resin having a melting point of 166 ° C. of differential scanning calorimetry and an isotactic pentad fraction of 96%, “Prime Polypro Y-2000GP” (manufactured by Prime Polymer Co., Ltd.) was 95% by weight. Others produced the transparent resin sheet using the same method as Example 1. At that time, using a differential scanning calorimeter DSC 6220 (manufactured by Seiko Instruments Inc.), the temperature was raised 10 ° C. per minute from 0 ° C. to 300 ° C., and the latent heat of fusion was measured to be 107 J / g.

<Comparative Example 7>
A transparent resin sheet was prepared in the same manner as in Example 1 except that “Notio PN-3560” (manufactured by Mitsui Chemicals) was increased to 96% by weight and “Y-2045GP” was decreased to 4% by weight. did. Using a differential scanning calorimeter DSC 6220 (manufactured by Seiko Instruments Inc.), the temperature was raised from 0 ° C. to 300 ° C. by 10 ° C. per minute, and the latent heat of fusion was measured to be 6.6 J / g.

<Solvent resistance>
Place the absorbent cotton impregnated with methyl ethyl ketone solvent on the side of the transparent resin sheet of Examples 1 to 4 and Comparative Examples 1 to 7 that is opposite to the primer-coated surface, and then use a watch glass to prevent volatilization. It was coated and left in a 25 ° C. environment for 24 hours. Thereafter, the surface of the transparent resin sheet was washed away with running tap water and further naturally dried for 72 hours to confirm the surface state.

<Weather resistance>
About the transparent resin sheet preparation of Examples 1-4 and Comparative Examples 1-7, Sunshine weather meter S-80BBR (Suga Test Instruments Co., Ltd. test conditions: Black panel temperature 63 degreeC, 50% of humidity in a tank, continuous irradiation mode (However, in the first 12 minutes every 60 minutes during continuous irradiation, pure water was sprayed on the surface of the sample)), and the deterioration of the sample was visually observed every 500 hours. At that time, the sample was set so that the light-irradiated surface was opposite to the primer-coated surface. Recording was performed by defining a time minus 500 hours from the time when an apparent shape change (deterioration, discoloration, etc.) began to occur on the transparent resin sheet surface as the weather resistance retention time of the sample.

<Wrapping aptitude>
After applying a solvent-based adhesive on the primer-coated surface side of the transparent resin sheets of Examples 1 to 4 and Comparative Examples 1 to 7, heating was performed at 60 ° C. for 3 minutes to volatilize the solvent, and the complex shape Wrapping was performed on the wood members that had been subjected to. The state of the member immediately after wrapping was confirmed, and the presence or absence of flaking or floating of the sheet from the wooden member was visually observed. Table 1 shows the evaluation results of each physical property.

  As can be seen from the results in Table 1, the transparent resin sheets of Examples 1 to 4 have a good balance of solvent resistance, weather resistance, and lapping suitability. However, the transparent resin sheets of Comparative Examples 1 to 7 are inferior to the transparent resin sheets of Examples 1 to 4 in any of solvent resistance, weather resistance, and lapping suitability. Furthermore, although not shown in Table 1, the texture which is closer to the real thing is also obtained by containing a true spherical filler.

  Since the transparent resin sheet of the present invention does not use any vinyl chloride, there is no concern about environmental problems. Furthermore, it has the performance which was excellent also in the solvent resistance which was the weak point of the acrylic resin type transparent resin sheet used until now.

DESCRIPTION OF SYMBOLS 1 ... Resin layer 2 ... Non-thermoplastic resin layer 3 ... Pattern pattern layer

Claims (3)

In the transparent resin sheet consisting of at least one resin layer used by bonding to the member surface,
The resin layer contains a polypropylene resin as a main component, and contains a resin component obtained by copolymerizing ethylene or α-olefin component based on propylene,
At least one layer of the resin layer contains an ultraviolet absorber and a light stabilizer,
The resin layer has a thickness of 50 to 300 μm,
A non-thermoplastic resin layer containing a UV absorber and a light stabilizer is laminated on the surface of the resin layer,
The non-thermoplastic resin layer contains a true spherical filler, characterized in that a part of the true spherical filler is exposed or raised on the outermost surface,
The transparent resin sheet, wherein the latent heat of fusion in the differential scanning calorimetry of the transparent resin sheet is in the range of 10 to 100 J / g. The transparent resin sheet according to claim 1 , wherein the spherical filler is made of inorganic glass. The transparent resin sheet according to any one of claims 1 to 2 , wherein a pattern layer is provided on the back surface of the resin layer.