JP2012140814A - Flooring material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flooring material having both an impact absorptivity for mitigating injuries due to falling and a scratch resistance on a surface thereof due to dents at a higher level compared with a flooring material attained by conventional techniques, and also capable of being used outdoors.SOLUTION: A decorative sheet has: an ultraviolet-curable acrylic surface protective layer; a transparent homo polypropylene resin layer whose isotactic pentad content is equal to or higher than 95%; and a pattern layer. A benzotriazole ultraviolet absorbent, a hydroxy phenyl triazine based ultraviolet absorbent, and a hindered amine based radical scavenger are at least added to the ultraviolet-curable acrylic surface protective layer as additive components. An additive amount of the benzotriazole ultraviolet absorbent is 0.1 - 2.0 with respect to 100 pts.wt. of an acrylic resin component as a base. A capsule foaming agent is used in a cushion layer based on ethylene-based materials.

Description

  The present invention relates to a flooring material that is used by fitting and laying a plurality of plate-like members, and can be used particularly for outdoor use, and has an impact absorption property for reducing injuries due to falls, In addition, the present invention relates to a flooring material having surface scratch resistance and suitability for construction by fitting.

  In recent years, flooring materials are often used for indoor floors. Known flooring materials include plywood, MDF, resin plates, etc., which are painted or bonded with a veneer, and laminates of decorative sheets. Conventionally, a flooring material in which a veneer is bonded to a plywood has been most commonly used. Wood flooring materials using natural wood, such as sticking veneer to plywood, have been widely accepted by consumers since the surface design is the most natural, friendly and beautiful design with natural wood grain. However, when exposed to sunlight, it tends to discolor, and when it gets wet, it easily swells, cracks, warps, corrodes, peels off the veneer, etc. It has been pointed out that there are problems with its use, such as the quality, price, and supply amount of the color tone, grain shape, etc., because it is a natural material.

  In order to avoid these problems, that is, for the purpose of stably supplying a flooring material that is durable and has a good color stability, a laminate with a decorative sheet as a substitute for a veneer has been proposed and spread. (For example, Patent Document 1). Furthermore, what uses the resin-type base material instead of the plywood is also proposed (for example, patent document 2).

  On the other hand, the flooring material is required to have a certain degree of hardness because the flooring material is required to have surface scratch resistance regardless of the material. However, on the other hand, since shock absorption is also required to reduce injuries due to falls, flexibility is also required. In order to balance this conflicting performance, our R & D group has been intensively studying, and as part of that, a cushion layer is provided on the surface side of the plate-like member, and a decorative sheet having scratch resistance is provided on the outermost surface. We examined the installation method, but it is difficult to balance sufficient shock absorption and scratch resistance, and in particular, balance resistance against so-called “push” such as pencil hardness and heavy load and shock absorption. I came to the conclusion that things were difficult. In addition to this, problems such as a worsening of walking feeling became apparent.

  Therefore, the flooring material which provides a cushion layer on the back surface side of a plate-shaped member was considered effective. According to this method, it has been shown that both shock absorption and scratch resistance are achieved (Patent Document 3). However, this patent shows that the desired performance can be obtained by defining the numerical value of the flexural modulus, but the material specifications are set to achieve a balance between shock absorption and scratch resistance at a higher level. There was room for consideration.

  In recent years, wood decks and stores with open spaces from indoors to outdoors have been increasing, but flooring materials that can be used for so-called outdoor applications are hardly present from the viewpoint of durability. It was.

JP2007-291836 JP 2010-106654 A

  The present invention has been made in order to solve such problems. That is, the problem is to provide shock absorption for reducing injuries due to falls, and resistance to scratches on the surface due to pressing. It is to provide a material that is compatible at a higher level than the flooring material obtained by the prior art and can be used for outdoor use.

  The present invention solves this problem, that is, the invention according to claim 1 is a plate-like member that can be laid by fitting a plurality of plate-like members by fitting shapes provided on the respective side surfaces thereof. In the flooring material, a decorative sheet is laminated on the front side of the plate-like member, and a cushion layer is laminated on the back side of the plate-like member, and the decorative sheet is isolated from the ultraviolet curable acrylic surface protective layer. At least a transparent homopolypropylene resin layer having a tactic pentad fraction of 95% or more and a patterned layer, and the ultraviolet curable acrylic surface protective layer has at least a benzotriazole ultraviolet absorber as an additive component, Hydroxyphenyltriazine UV absorber and hindered amine radical scavenger are added, and the benzotriazole UV absorber is added. The agent is added in an amount of 0.1 to 2.0 parts by weight with respect to 100 parts by weight of the acrylic resin component of the base, and the cushion layer uses a capsule foaming agent based on an ethylene-based material. This flooring material is characterized by being foamed.

  The invention according to claim 2 is the flooring material according to claim 1, wherein the ethylene material of the cushion layer is an ethylene / vinyl acetate copolymer resin.

  The invention according to claim 3 is characterized in that the ethylene / vinyl acetate copolymer resin is ethylene / vinyl acetate copolymer resin = 60/40 to 85/15 in terms of monomer units. In the flooring material.

  The invention according to claim 4 is characterized in that the foaming ratio of the cushion layer is 3.0 times or more and 10 times or less, and the thickness of the cushion layer is 4 mm or more and 9 mm or less. The flooring material according to any one of the above.

  The invention according to claim 5 is characterized in that a second cushion layer foamed using a capsule foaming agent based on an ethylene-based material is provided between the plate-like member and the decorative sheet. It is a flooring material in any one of Claims 1-4.

  The invention according to claim 6 is the flooring material according to claim 5, wherein the foaming ratio of the second cushion layer is 1.5 times or more and 3.0 times or less.

  According to the first aspect of the present invention, it is possible to achieve both impact absorbability and scratch resistance at a high level. In particular, by using a UV curable acrylic surface protective layer and a transparent homopolypropylene resin layer having an isotactic pentad fraction of 95% or more for the decorative sheet, the scratch resistance can be maintained at a high level. In particular, by using an ultraviolet curable acrylic surface protective layer, it is possible to obtain a flooring material that is harder than the isocyanate curable type, less yellowing than the electron beam curable type, and has high durability. In addition, by using an ethylene material as the cushion layer material, it is possible to obtain a sufficient melt tension for foaming even though it is an olefin material. As a result, a cushion layer with less variation in the expansion ratio is obtained. I can do things. In addition, by using a capsule foaming agent as the foaming agent, closed cells that are difficult to obtain with a chemical foaming agent can be obtained, so that a cushion layer with little variation in foaming ratio can be obtained. Furthermore, since it is a closed cell, the compressive strain recovery property of a cushion can be improved more. The foaming by the capsule foaming agent is mainly performed in the thickness direction, which contributes to the improvement of compressive strain recovery. Due to these effects, it is possible to achieve both shock absorption and scratch resistance at a high level. In addition, by properly combining a benzotriazole-based ultraviolet absorber, a hydroxyphenyltriazine-based ultraviolet absorber, and a hindered amine-based radical scavenger, a decorative sheet having high weather resistance can be provided without causing poor curing due to ultraviolet irradiation.

  According to the second aspect of the present invention, by using an ethylene / vinyl acetate copolymer resin as a material for the cushion layer, stable foaming can be obtained while maintaining appropriate crystallinity. According to the invention, in the ethylene / vinyl acetate copolymer resin, the copolymer of ethylene and vinyl acetate is copolymerized within the range of ethylene / vinyl acetate copolymer resin = 60/40 to 85/15 in a monomer unit ratio. It is possible to make the layer an optimum condition, and as a result, it is possible to achieve a higher level of both shock absorption and scratch resistance. By setting the amount of ethylene to 60 or more in the monomer ratio, it is possible to obtain appropriate crystallinity, and it is possible to obtain more suitable rigidity while maintaining sufficient cushioning properties. By setting the amount of ethylene to 95 or less in the monomer ratio, it is possible to suppress the crystallinity from becoming too high, and it is possible to obtain more suitable cushioning properties while maintaining sufficient rigidity. The ratio of ethylene and vinyl acetate is more preferably ethylene / vinyl acetate copolymer resin = 65/35 to 80/20, and more preferably 70/30 to 77/23 in terms of monomer units.

  Furthermore, according to the invention of the fourth aspect of the present invention, by defining the physical shape of the cushion layer, it is possible to impart more optimal shock absorption and scratch resistance. By setting the foaming ratio of the cushion layer to 3 times or more and the thickness of the cushion layer to 4 mm or more, more suitable shock absorption can be obtained, and further, the foaming ratio of the cushion layer is 10 times or less. By setting the thickness to 9 mm or less, it is possible to obtain more suitable scratch resistance (particularly, resilience against pressing scratches).

  By providing the second cushion layer between the plate-like member and the decorative sheet as the impact preabsorption layer, it is possible to further improve the impact absorbability. In that case, since the 2nd cushion layer provided between a plate-shaped member and a decorative sheet is closer to a surface layer surface than the cushion layer provided in the back surface of a plate-shaped member, it is the 2nd provided between a plate-shaped member and a decorative sheet. The foaming ratio of the surface layer is within the range of 1.5 times or more and 3.0 times or less, and the foaming ratio is set lower than the cushion layer laminated on the back side of the plate-like member, thereby reducing the scratch resistance of the surface. Impact absorption performance can be imparted while keeping to a minimum. That is, when the expansion ratio is 1.5 times or more, the performance as a cushion is exhibited, and when it is 3.0 times or less, scratch resistance of the surface is obtained.

It is explanatory drawing which shows the shape of the cross section of one Example of the flooring material of this invention. It is explanatory drawing which shows the shape of the cross section of one Example of the flooring material of this invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the above drawings and descriptions as long as they are within the scope of the claims of the present invention. FIG. 1 shows a cross-sectional shape of an embodiment of the flooring material of the present invention. A decorative sheet 2 is provided on one side of the plate-like member 1, and a cushion layer 3 is provided on the opposite layer. Further, an adhesive layer 4 and an adhesive layer 5 are provided as appropriate in order to improve the adhesion of each laminated surface. The decorative sheet 2 includes a surface protective layer 21, a transparent polypropylene resin layer 22, a pattern layer 23, and a colored raw fabric layer 24.

  As the cushion layer 3 in the present invention, a foam layer made of an ethylene-based material using a capsule foaming agent is used. Ethylene is one of the most commonly used olefin materials, and low density polyethylene and ethylene / vinyl acetate copolymer resins have a long-chain branching component, so they can maintain a high melt tension during melt foaming. Therefore, foam molding is easy. Moreover, moderate flexibility of the ethylene-based material imparts moderate shock absorption. In addition, unlike vinyl chloride resin, ethylene-based materials are also suitable because there is no concern of generating toxic gas during combustion or bleeding out plasticizer components that remain a concern for environmental hormones. . In addition, the specific gravity of polyethylene is about 0.9, which is lower than that of other plastic materials, which is preferable from the viewpoint of weight reduction.

  Examples of the ethylene-based material include low-density polyethylene, medium-density polyethylene, high-density polyethylene, and ethylene / α-olefin copolymer (for example, propylene, 1-butene, 1-pentene, 1-hexene are used as α-olefins). 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl -1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11 -Methyl-1-dodecene, 12-ethyl-1-tetradecene or the like is used), ethylene / vinyl acetate copolymer, ethylene / vinyl alcohol copolymer, ethylene / methyl methacrylate copolymer, There are ethylene / ethyl methacrylate copolymer, ethylene / butyl methacrylate copolymer, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / butyl acrylate copolymer, etc. Selected.

  Among these ethylene-based materials, ethylene / vinyl acetate copolymer resin is preferably used when considering flexibility, economic efficiency, freedom in setting the ratio of ethylene and comonomer, etc. By copolymerizing within a range of ethylene / vinyl acetate copolymer resin = 60/40 to 85/15 by the ratio of monomer units, it becomes possible to make the cushion layer an optimum condition, and as a result, shock absorption It is possible to achieve a higher level of both resistance and scratch resistance.

  In order to achieve both impact absorption and scratch resistance, selection of these materials is important, but factors such as expansion ratio and thickness are also important. Like the present invention, by setting the foaming ratio of the cushion layer to 3 times or more and the thickness of the cushion layer to 4 mm or more, more suitable shock absorption can be obtained, and further, the foaming ratio of the cushion layer is 10 times. Further, by setting the thickness of the cushion layer to 9 mm or less, it is possible to obtain more suitable scratch resistance (particularly, resilience against pressing scratches). Foaming agents for foaming are broadly classified into chemical foaming agents and capsule foaming agents. By selecting a capsule foaming agent, both impact absorption and scratch resistance can be achieved at a high level.

  As the decorative sheet 2 in the present invention, a pattern layer 23 for imparting designability is provided on the colored raw fabric layer 24 for concealing the plate-like member 1 by printing or the like, and the transparent polypropylene resin layer 22 is sandwiched to protect the surface. What provided the layer 21 is used. The concealability may be imparted by providing the pattern layer 23 as a solid print layer (not shown), or the colored raw fabric layer 24 may be transparent if the concealability is not required. Among these, a transparent homopolypropylene resin having an isotactic pentad fraction of 95% or more is used for the transparent polypropylene resin layer 22. The isotactic pentad fraction is a fraction bonded to isotactic five continuous monomers in the polymer molecular chain, and is measured using 13C-NMR. In other words, in polypropylene, it is defined as a fraction representing the proportion of propylene monomer in which five methyl groups are continuously oriented in the same direction with respect to the total number of propylene monomers in monomer units. The isotactic pentad fraction is an index indicating the high regularity of the polypropylene resin. The higher this value, the closer to the original polypropylene resin, the more rigid decorative sheet can be obtained. A decorative sheet having good adhesion and the flooring material of the present invention using the same can be obtained.

  The theoretical maximum value of the pentad fraction is 100%, but about 98 to 99% is practically the upper limit value for commercial use due to the performance of the catalyst, the influence of impurities, and the like. In the present invention, it was found that sufficient scratch resistance can be obtained by setting it to 95% or more.

  As the surface protective layer 21 of the decorative sheet in the present invention, an ultraviolet curable type is used. Other curing methods include an isocyanate curable type, an electron beam curable type, a method of laminating a thermoplastic resin, and a method of not providing a surface protective layer in the first place. However, each flooring has a drawback.

  For example, in the case of an isocyanate curable type, since a urethane bond can be formed in the course of the reaction, the flexibility resulting from urethane lowers scratch resistance. In the case of the electron beam curable type, a large amount of free radicals are generated in the surface protective layer by irradiating a strong energy electron beam. Therefore, an antioxidant, which is an additive component in the surface protective layer, UV absorbers cause yellowing. Moreover, since the influence of an electron beam extends not only in a surface protective layer but the whole decorative sheet, it will also yellow the inside of the said transparent resin layer, for example. In order to suppress the yellowing effect, there is no choice but to change the ultraviolet absorber, the antioxidant, etc. to a type that is difficult to yellow, and the degree of freedom of material selection is reduced.

  When a thermoplastic resin is laminated as the surface protective layer, the material of the surface protective layer does not undergo a three-dimensional crosslinking reaction, so the shape can be easily changed by heat, and the additive component can be easily changed over time. However, it is not suitable because it bleeds out. The method of not providing the surface protective layer is also not suitable because of the influence on the deterioration of various physical properties such as scratch resistance, contamination resistance, and weather resistance.

  On the other hand, in the case of the ultraviolet curable type, it is possible to obtain a layer having the same level of hardness as the electron beam curable type without causing problems such as yellowing due to radicals generated in large quantities by the electron beam. it can. Also, the facility for irradiating ultraviolet rays is simpler than the facility for irradiating an electron beam, and can be downsized. As a possible disadvantage, since it is an ultraviolet curable type, depending on the type of the ultraviolet absorber added to the surface protective layer, there is a concern that the ultraviolet absorber may inhibit curing, but an ultraviolet reaction occurs. Using the fact that the wavelength at which the photopolymerization initiator, which is the “seed”, varies depending on the type, reacts in a wavelength region that does not contribute to deterioration of the surface protective layer, and the ultraviolet absorber also absorbs in this wavelength region. This can be avoided by taking measures such as selecting ones that do not.

  Specifically, as in the present invention, a combined use of a hydroxyphenyl triazine-based UV absorber, a benzotriazole-based UV absorber, and a hindered amine-based radical scavenger, and the addition amount of the benzotriazole-based UV absorber is 0. It may be in the range of .1 to 2.0 parts by weight. Hydroxyphenyltriazine-based UV absorbers do not affect polymerization because the UV absorption wavelength region is on the lower wavelength side than the reaction region of the photopolymerization initiator, but the resin has no C = C bond or C = O bond. Since it has a high absorption capability in a wavelength region (specifically, 290 to 330 nm) that cuts and degrades the resin, it can have high weather resistance. The benzotriazole-based UV absorber absorbs in the longer wavelength region than the hydroxyphenyltriazine-based UV absorber and partially suffers from the reaction wavelength of the photopolymerization initiator, but the addition amount is 0.1-2.0 parts by weight By doing so, the influence of crosslinking inhibition can be limited.

  The surface protective layer 21 may be a hybrid resin of ultraviolet curing and isocyanate curing. In that case, both the case of simply blending an ultraviolet curable resin and an isocyanate curable resin, and a functional group that reacts with ultraviolet rays and a functional group that reacts with isocyanate are added in advance to the resin before crosslinking. There are methods, but you can choose either one. In either case, however, the main cross-link must be UV curable.

  As the material for the surface protective layer 21, an acrylic material is used. In view of weather resistance, a methacrylate type is desirable. Among them, a resin based on methyl methacrylate is particularly desirable.

  The thickness of the surface protective layer 21 is not particularly specified, but is preferably about 3 to 20 μm. If it is 3 μm or less, it is difficult to give sufficient scratch resistance and weather resistance, and if it is 20 μm or more, the effect of improving scratch resistance by increasing the thickness is hardly seen, but it is not preferable in terms of handling and economy. There is.

  The cushion layer 3 and the plate-like member 1 to be described later are appropriately bonded using an adhesive layer 5. Specific examples include a two-component urethane water-based adhesive, a one-component vinyl acetate resin emulsion-based adhesive, a moisture-curable urethane resin-based hot-melt adhesive, and the like. If it is a woody resin base material which mix | blended wood powder and talc with the polyolefin resin to do, a moisture hardening type urethane type hot-melt-adhesive is used suitably. The thickness is preferably about 10 to 100 μm after drying.

  As the plate-like member 1 in the present invention, any plate member can be used as long as it is used as a plate-like member of a known flooring material. The thickness is preferably 4 to 5 mm. As a constituent material, plywood, MDF, wood resin and the like can be used without particular limitation. For example, 100 to 30 parts by weight of polyolefin resin and 10 to 30 parts by weight of wood powder and 5 to 15 parts by weight of talc are melt extruded. What consists of a molded wood resin base material is used suitably. The same polyolefin resin as that used in the cushion layer 3 can be used. Moreover, you may add a foaming agent and foam about 1-2 times. Further, mica, a heat stabilizer, a compatibilizer for these, and the like may be added as appropriate.

  What is necessary is just to adhere | attach the said plate-shaped member 1 and the decorative sheet 2 using the adhesive bond layer 4 suitably. Specific examples include two-component urethane water-based adhesives, one-component vinyl acetate resin emulsion-based adhesives, and moisture-curing urethane resin-based hot melt adhesives. Specifically, wood flour and talc are added to polyolefin-based resins. If it is the colored raw fabric layer 24 of the decorative sheet 2 based on the blended plate-like member 1 and a polyolefin resin sheet to be described later, a moisture-curable urethane hot melt adhesive is preferably used. The thickness is preferably about 10 to 100 μm after drying.

  Furthermore, as shown in FIG. 2, it is also preferable to further provide a second cushion layer 7 between the plate-like member 1 and the decorative sheet 2. Since the second cushion layer 7 serves as a preliminary absorption layer for impact, a more suitable impact absorption capability is exhibited. The expansion ratio of the second cushion layer 7 is desirably in the range of 1.5 to 3 times. By setting the expansion ratio lower than that of the cushion layer 3 provided on the back surface of the plate-like member 1, it is possible to impart impact absorbing performance while minimizing the deterioration of the scratch resistance on the surface. The thickness of the second cushion layer 7 is not particularly limited, but if it is too thick, there is a risk of impairing walking during walking, and if it is too thin, the effect of providing the second cushion layer 7 is limited. Therefore, care must be taken.

  Hereinafter, effects of the present invention will be clarified based on examples.

<Creation of plate member 1>
Homopolypropylene resin: To 70 parts by weight of E-105GM (manufactured by Prime Polymer Co., Ltd.), after adding 10 parts by weight of talc and 20 parts by weight of wood flour, melt mixing at an extrusion temperature of 200 ° C. with a twin screw extruder, A pelletized material was produced. On the other hand, a 5 mm thick, 150 mm wide, real mold is attached to the tip of a single-screw extruder, and a chemical foaming agent: Spancel DS # 25 (manufactured by Eiwa Kasei Co., Ltd.) is added to the pelletized material to form a different shape. Extrusion was performed. The amount of the foaming agent was added while appropriately adjusting so that the expansion ratio was 1.6 times. A cooling mold having the same shape as the actual shape mold, in which cooling water was circulated, was provided at the tip of the actual shape mold, and the molded product extruded from the die was drawn as it was to be cooled and solidified. Furthermore, after completely cooling in the water tank which stored cooling water, after removing the water droplet adhering to a molding by air drying, it cut | disconnected to length 900mm. This molded product was heated in an oven at 80 ° C. for 20 hours to complete crystallization, and the strain generated in the resin was alleviated to obtain a plate-like member.

<Preparation of cushion layer 3>
Ethylene / vinyl acetate copolymer resin: Everflex EV360 (manufactured by Mitsui DuPont Polychemical Co., Ltd .; ethylene amount 75%), 100 parts by weight of black pigment, 3 parts of capsule, capsule foaming agent: Matsumoto Microspher F-79 (Matsumoto Yushi Seiyaku Co., Ltd.) was added in an appropriate amount from each side feed, extruded and foamed from a 160 ° C. T-die extruder, and then continuously introduced into a 210 ° C. vertical hot air foaming machine. Double and 6 mm thick cushion layer 3 was obtained. The addition amount of the capsule foaming agent was appropriately adjusted so that the expansion ratio was 8 times.

<Preparation of the second cushion layer 7>
A second cushion layer 7 was obtained by substantially the same manufacturing method as the cushion layer 3. However, depending on the control of the amount of foaming agent and the molding speed, the layer for the second cushion layer 7 may be (1) foaming magnification 2.1 times, thickness 3 mm (2) foaming magnification 1.3 times, thickness 3 mm, (3 ) Three types of foaming magnification of 6 times and thickness of 3 mm were prepared.

<Preparation of decorative sheet 2>
As the colored raw fabric layer 24, a random polypropylene resin having a melting point of 140 ° C. measured by differential scanning calorimetry (DSC), ethylene content of 4% in monomer units, 6% by weight of titanium oxide, and Irga as a phenolic antioxidant. 0.2% by weight of Knox 1076 (manufactured by BASF Japan Co., Ltd.), Irfugaphos 168 (manufactured by BASF Japan Co., Ltd.) as a phosphorus processing stabilizer, Kimamasorb 2020 (manufactured by BASF Japan Co., Ltd.) as a hindered amine light stabilizer Using 0.3% by weight of each added resin, a T-die extruder was used to melt and extrude the sheet at an extrusion temperature of 200 ° C. and an extrusion thickness of 70 μm, and both surfaces were subjected to corona treatment.

  On the colored original fabric layer 24, a wood grain pattern was applied as a pattern layer 23 by a gravure printing method using pattern ink (manufactured by Toyo Ink Manufacturing Co., Ltd .; Lamister). On the other hand, 15 parts by weight of silica having an average particle shape of 6 μm was added to the base resin component (the remaining component excluding the pigment) of Lamister ink on the surface opposite to the pattern-like ink.

  On the pattern layer 23, an isocyanate-curing dry laminate adhesive Takelac A-520 (main agent: manufactured by Mitsui Chemicals), Takenate A-80 (hardener: manufactured by Mitsui Chemicals), main agent / curing After blending with an agent = 9/1 and adjusting to 30% solid content with an ethyl acetate solvent, it was applied to a solid content thickness of about 5μm by gravure printing and dried in an oven at 60 ° C for 2 minutes. The solvent component was volatilized.

  As the transparent polypropylene resin layer 22, 99 parts by weight of a homopolypropylene resin (manufactured by Prime Polymer Co., Ltd.) having a pentad fraction of 96% and MFR = 18 was added to an ultraviolet absorber: Tinuvin 326 (manufactured by BASF Japan Co., Ltd.). 5 parts by weight, light stabilizer: 0.5 part by weight of Tinuvin 783 (manufactured by BASF Japan Ltd.) was added, melt kneaded and extruded at an extrusion temperature of 230 ° C., and cast into a film by a T-die to obtain a sheet. .

  After the corona treatment is performed on both the front and back surfaces of the obtained sheet, the colored raw fabric layer 24 is bonded to the coated surface side of the isocyanate-curable dry laminating adhesive, and then, for 3 days in a 60 ° C. environment. Aging was performed.

  Further, as the surface protective layer 21, 5 parts by weight of TINUVIN 400 (manufactured by BASF Japan Ltd.) as a hydroxyphenyltriazine UV absorber is based on an acrylic UV curable resin UVT clear (manufactured by DIC Graphics Co., Ltd.). After adding 1 part by weight of tinuvin 328 (manufactured by BASF Japan) as a triazole-based UV absorber and 5 parts by weight of tinuvin 152 (manufactured by BASF Japan) as a hindered amine radical scavenger, the thickness is 10 μm by a gravure coating method. After lamination on the outermost layer (after solvent volatilization), irradiation was performed for 10 seconds with an ultraviolet irradiation device using a metal halide lamp as a light source. Thus, a decorative sheet 2 was obtained.

  Ricabond BA-10L (manufactured by Chuo Rika Kogyo Co., Ltd.) as an adhesive 4 was applied to one side of the plate-like member 1 thus produced so that the wet state was 70 g / square m, and a decorative sheet 2 was further bonded. . Thereafter, a moisture-curing urethane resin hot melt adhesive: Tyforce (manufactured by DIC Corporation) is applied to the other surface of the plate-like member as the adhesive 5 so that the thickness after drying becomes 50 μm. Furthermore, the cushion layer 3 was bonded together. Thus, the flooring material of Example 1 obtained by laminating the decorative sheet 2 / adhesive 4 / plate member 1 / adhesive 5 / cushion layer 3 in this order was obtained.

  By changing the foaming ratio and thickness of the cushion layer 3 as shown in Table 1, flooring materials of Examples 2 to 5 were obtained. At this time, the expansion ratio was controlled by adjusting the amount of capsule foaming agent added, and the thickness was adjusted by changing the production rate in addition to the amount of foaming agent added.

  By changing the ethylene / vinyl acetate copolymer resin from EV 360 as shown in Table 1, flooring materials of Examples 6 to 7 were obtained. The ethylene ratio of EV45LX is 55%, and the ethylene ratio of EV560 is 86%.

  Flooring of Example 8 using the same method as Example 1 except that MFR = 7 low density polyethylene resin: Novatec LC600A (manufactured by Nippon Polyethylene Co., Ltd.) was used instead of ethylene / vinyl acetate copolymer resin. The material was obtained.

  The 2nd cushion layer 7 was provided between the decorative sheet 2 and the plate-shaped member 1, and the flooring materials of Examples 9-11 were obtained. At this time, the adhesive layer 4 between the second cushion layer 7 and the plate member 1 has a moisture curable urethane resin hot melt adhesive: Tyforce (manufactured by DIC Corporation) on the plate member 1 side. Was applied so that the thickness after drying was 50 μm, and the second cushion layer 7 was further bonded. On the other hand, Takelac A-520 (main agent; manufactured by Mitsui Chemicals) and Takenate A-80 (hardener; manufactured by Mitsui Chemicals) are used as the main component / After blending with a curing agent = 9/1 and adjusting to 30% solid content with an ethyl acetate solvent, it is applied by gravure printing so that the solid content thickness is about 5 μm, and in an oven at 60 ° C. for 2 minutes The solvent component was volatilized by drying. By attaching the decorative sheet 2 and the second cushion layer 7 through this adhesive, decorative sheets of Examples 9 to 11 were obtained.

<Comparative Example 1>
The flooring material of Comparative Example 1 was used in the same manner as in Example 1 except that an MFR = 20 ethylene random polypropylene resin: Prime PP Y-2045GP (manufactured by Prime Polymer Co., Ltd.) was used as the transparent polypropylene resin layer 22. Got.

<Comparative example 2>
As the surface protective layer 21, 5 parts by weight of TINUVIN 400 (manufactured by BASF Japan) as a hydroxyphenyltriazine-based UV absorber and benzotriazole-based UV are used as a base based on an isocyanate curable resin UC clear (manufactured by DIC Graphics). 1 part by weight of TINUVIN 328 (manufactured by BASF Japan Ltd.) as an absorbent and 5 parts by weight of TINUVIN 152 (manufactured by BASF Japan KK) as a hindered amine-based radical scavenger were stirred and added, and then 10 μm thick (solvent volatilization) by a gravure coating method. The flooring material of Comparative Example 2 was obtained using the same method as in Example 1 except that the film was laminated on the outermost layer in the latter) and then subjected to heat curing in an oven at 60 ° C. for 72 hours.

<Comparative Example 3>
The surface protective layer 21 is based on an electron beam curable resin EBT clear (manufactured by DIC Graphics Co., Ltd.), 5 parts by weight of tinuvin 400 (manufactured by BASF Japan Co., Ltd.) as a hydroxyphenyltriazine-based ultraviolet absorber, and benzotriazole-based 1 part by weight of TINUVIN 328 (manufactured by BASF Japan Ltd.) as an ultraviolet absorber and 5 parts by weight of TINUVIN 152 (manufactured by BASF Japan KK) as a hindered amine radical scavenger were stirred and added, and then a thickness of 10 μm (solvent) by gravure coating method. A flooring material of Comparative Example 3 was obtained using the same method as in Example 1 except that it was laminated on the outermost layer after volatilization and irradiated with an electron beam of 10 kGy.

<Comparative example 4>
A flooring material of Comparative Example 4 was obtained using the same method as in Example 1 except that the foaming agent used for the cushion layer 3 was chemical foaming agent: Spancel DS # 25 (manufactured by Eiwa Kasei Co., Ltd.).

<Comparative Example 5>
A flooring material of Comparative Example 5 was obtained in the same manner as in Example 1 except that the cushion layer 3 and the adhesive layer 5 were not provided.

<Comparative Example 6>
A flooring material of Comparative Example 6 was obtained in the same manner as in Example 1 except that Tinuvin 400 was not added and instead Tinuvin 328 was increased from 1 part by weight to 6 parts by weight.

<Comparative Example 7>
A flooring material of Comparative Example 7 was obtained in the same manner as in Example 1 except that 6 parts by weight of Tinuvin 400 was added and Tinuvin 328 was not added.

<Comparative Example 8>
A flooring material of Comparative Example 8 was obtained in the same manner as in Example 1 except that 3 parts by weight of Tinuvin 400 and 3 parts by weight of Tinuvin 328 were increased from 1 part by weight.

<Evaluation method>
The following evaluation was performed about the produced flooring materials of Examples 1-11 and Comparative Examples 1-5.
Appearance evaluation: Confirmed by visual inspection for discoloration, cracks, floats, and deformation.
Dent and crack test: A 16-pound (7.25 kg) bowling ball was dropped from a height of 1 m, and dents and cracks were confirmed.
Impact resistance test: Gs value was measured by a method based on JIS A6519.
Pencil scratch test: Pencil hardness is measured by a method according to JIS K5600.

  Further, the flooring materials of Example 1 and Comparative Examples 6 to 8 were tested with a sunshine weather meter (black panel 63 ° C., humidity 50% RH, shower spray for 12 minutes in 60 minutes), and surfaced every 500 hours. The time when deterioration or discoloration starts was checked.

<Test results>
The evaluation results are shown in Tables 2 and 3.

  As can be seen from Table 2, the flooring material of Example 1 has a balance of all evaluation items. Further, as in Examples 9 to 11, by providing the cushion layer 3 between the decorative sheet 2 and the plate-like member 1, the pencil hardness value slightly decreases, but the flooring material further improved in impact resistance. It has become. From the results of Examples 2 to 5, it can be seen that changing the balance of the thickness of the cushion layer 3 and the foaming ratio affects the respective characteristic values. In addition, it can be seen from the results of Examples 6 to 8 that the characteristic value is also influenced by the material of the cushion layer. From a bird's-eye view of the results of Examples 1 to 8, it can be seen that Example 1 is most balanced overall.

  On the other hand, it can be seen that the flooring materials of Comparative Examples 1 to 5 are insufficient in both pencil scratch performance and impact resistance performance.

  Moreover, it turns out that the weather resistance performance of Example 1 is excellent from Table 3 compared with Comparative Examples 6-8. This is considered to be because UV crosslinking did not proceed sufficiently in Comparative Examples 6 and 8 because the benzotriazole UV absorber was excessive, and in Comparative Example 7 the benzotriazole UV absorber was not added. This is probably because the absorption wavelength is too biased toward a low wavelength.

  The flooring material of the present invention can be used not only on an indoor floor surface but also on an outdoor floor surface.

DESCRIPTION OF SYMBOLS 1 ... Plate-shaped member 2 ... Cosmetic sheet 21; Surface protection layer 22; Transparent polypropylene resin layer 23; Pattern layer 24; Colored raw fabric layer 3 ... Cushion layer 4 ... Adhesive layer 5 ... Adhesive layer 7 ... Second cushion layer

Claims (6)

  In a flooring material comprising a plate-like member that can be laid by fitting with a fitting shape provided on each side surface of a plurality of plate-like members, a decorative sheet is laminated on the surface side of the plate-like member, and the plate-like member A cushion layer is laminated on the back side of the member, and the decorative sheet comprises at least an ultraviolet curable acrylic surface protective layer, a transparent homopolypropylene resin layer having an isotactic pentad fraction of 95% or more, and a pattern layer. And the ultraviolet curable acrylic surface protective layer has at least a benzotriazole ultraviolet absorber, a hydroxyphenyltriazine ultraviolet absorber, and a hindered amine radical scavenger as additive components, The benzotriazole-based UV absorber is at least 0.1 part by weight based on 100 parts by weight of the base acrylic resin component. 0 is an amount of less parts by weight, besides the cushion layer, characterized in that it is made by foaming using a capsule foaming agent based on ethylene-based material, flooring material.   The flooring material according to claim 1, wherein the ethylene material of the cushion layer is an ethylene / vinyl acetate copolymer resin.   3. The flooring material according to claim 2, wherein the ethylene / vinyl acetate copolymer resin is ethylene / vinyl acetate copolymer resin = 60/40 to 85/15 in a monomer unit ratio.   The flooring material according to any one of claims 1 to 3, wherein the foaming ratio of the cushion layer is 3.0 to 10 times, and the thickness of the cushion layer is 4 to 9 mm.   It has the 2nd cushion layer made to foam using the capsule foaming agent based on the ethylene-type material between the said plate-shaped member and a decorative sheet, The any one of Claims 1-4 characterized by the above-mentioned. The flooring material described.   The flooring material according to claim 5, wherein a foaming ratio of the second cushion layer is 1.5 times or more and 3.0 times or less.

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