JP2017100398A - Multilayer resin sheet, laminated sheet, method for producing multilayer resin sheet, method for producing laminated sheet, and method for producing foamed wall paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer resin sheet which can be efficiently produced by extrusion molding while having a resin layer containing a foaming agent; a laminated sheet and a method for producing them; and a method for producing foamed wall paper.SOLUTION: In a multilayer resin sheet 20 having a first layer 1 formed from a foaming agent-containing resin composition that contains a first resin content, a filler and a foaming agent, and a second layer 2 formed from a foaming agent-free resin composition that contains a second resin content and does not contain a foaming agent, a thickness Tof the first layer 1 is smaller than a thickness Tof the second layer 2. Tand Tsatisfy a relationship of the following expression: T×2≤T. The first resin content contains an ethylene-vinyl acetate copolymer or an ethylene copolymer having a melting point of 100°C or lower, and a silane crosslinkable resin.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a multilayer resin sheet, a laminated sheet, a method for producing a multilayer resin sheet, a method for producing a laminated sheet, and a method for producing foamed wallpaper. More specifically, the present invention relates to a method for producing foamed wallpaper that can be used for wall decoration of buildings such as detached houses, apartment houses, stores, office buildings, etc., multilayer resin sheets and laminated sheets used therefor, and these It relates to the manufacturing method.

  As wallpaper used for wall decoration of buildings, etc., vinyl chloride resin foam wallpaper and plastic foam wallpaper in which a paper base is provided with a resin layer of vinyl chloride resin or other plastics are widely used.

  As a method for producing these foamed wallpaper, a resin composition containing a foaming agent is laminated on a base material while being formed into a sheet by a melt extrusion molding method such as a T-die, or separately sheeted and later dry laminated. Alternatively, there is a method in which a base sheet is bonded by thermal lamination to obtain a laminated sheet in which a resin sheet is provided on the base material, and then a resin sheet whose surface is printed is foamed as necessary. (For example, refer to Patent Document 1 below). These methods are advantageous in terms of production efficiency as compared with a coating method in which a resin composition is applied and dried on a substrate and a calendering method.

  As a technique for improving the surface strength of foamed wallpaper, a foamed wallpaper in which a non-foamed resin layer is provided on a foamed resin layer has been proposed (see, for example, Patent Documents 2 and 3 below).

Patent No. 4629188 JP 2007-31893 A JP 2007-313900 A

  When a multilayer resin sheet having a resin layer containing a foaming agent is produced by extrusion molding, the extrusion molding of the resin composition containing the foaming agent is performed at a low temperature and low so that the foaming agent is not decomposed by shearing heat generation during extrusion molding. It is necessary to carry out under the condition of screw rotation. Therefore, also in the manufacture of the laminated sheet for foamed wallpaper having the non-foamed resin layer as described above, the formation of the resin layer containing the foaming agent becomes rate-limiting. Moreover, also when co-extrusion molding with the resin composition which does not contain a foaming agent, the film-forming speed | rate will be restrict | limited for ensuring film-forming stability of the resin composition containing a foaming agent.

  The present invention has been made in view of the above circumstances, and has a multilayer resin sheet that can be efficiently produced by extrusion while having a resin layer containing a foaming agent, a laminated sheet, and a production method thereof, and It aims at providing the manufacturing method of foam wallpaper.

In order to solve the above problems, the present invention includes a first resin component, a filler, and a first layer composed of a foaming agent-containing resin composition containing a foaming agent, and a second resin component, a multilayer resin sheet and a second layer of not including a foaming agent foaming agent-containing resin composition, the thickness T ₁ of the first layer is smaller than the thickness T ₂ of the second layer, the multilayer resin sheet provide.

  According to the multilayer resin sheet of the present invention, when the thickness of the first layer containing the foaming agent is made smaller than the thickness of the second layer not containing the foaming agent, each layer is formed by extrusion molding. The difference in film forming speed can be reduced, or a decrease in film forming speed when coextrusion molding can be suppressed. Thereby, the improvement of the production efficiency of the foam wallpaper which has a non-foaming resin layer can be anticipated. Furthermore, according to the multilayer resin sheet of the present invention, since the thickness of the second layer can be increased without significantly reducing the productivity, the scratch resistance of the foamed wallpaper can be further improved.

The T ₁ and T ₂ preferably satisfy the relationship of T ₁ × 2 ≦ T ₂ . In this case, the effects of the present invention described above can be obtained more easily.

  The multilayer resin sheet of the present invention may further include a third layer comprising a second foaming agent-free resin composition containing a third resin component and no foaming agent. In this case, the foaming agent-containing resin composition can be sandwiched between two foaming agent-free resin compositions and co-extrusion molding can be performed. Problems caused by the contact between the foaming agent and the die, for example, the edge of the discharge port It is possible to reduce the phenomenon of foreign matter adhering to the portion (so-called “eyes discoloration”) and to further improve productivity.

  The first resin component preferably contains a resin having a melting point of 100 ° C. or lower. By including such a resin, low temperature molding becomes possible, and decomposition of the foaming agent during extrusion molding can be more efficiently suppressed. Further, such a resin is more preferably an ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer. By including an ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer, the extensional viscosity in the first layer can be ensured, so that the foam cell when foaming the foaming agent becomes finer and more A foam wallpaper having a good foaming state can be obtained.

  The first resin component preferably contains a silane crosslinkable resin. By including the silane crosslinkable resin in the first resin component, only the first layer can be selectively crosslinked. Accordingly, when the first layer is foamed, the followability of the second layer with respect to the first layer can be improved, so that the adhesion between both layers can be improved and the surface strength can be improved. Further, when the first resin component is cross-linked, it is not necessary to cross-link by electron beam irradiation or heat, and yellowing of the base material or resin can be suppressed.

  Moreover, this invention provides a laminated sheet provided with a base material and the multilayer resin sheet which concerns on the said this invention provided on this base material.

  Furthermore, this invention is a manufacturing method of the multilayer resin sheet which concerns on the said invention, Comprising: The said 1st layer and the above-mentioned by extrusion-molding the said foaming agent containing resin composition and the said foaming agent non-containing resin composition, respectively. A step of forming a second layer, or a step of forming the first layer and the second layer by coextrusion molding at least the foaming agent-containing resin composition and the foaming agent-free resin composition, A method for producing a multilayer resin sheet is provided. According to the method for producing a multilayer resin sheet of the present invention, a multilayer resin sheet having a resin layer containing a foaming agent and a resin layer containing no foaming agent can be efficiently produced.

  In the method for producing a multilayer resin sheet, when the multilayer resin sheet further includes the third layer, at least a foaming agent-free resin composition, a foaming agent-containing resin composition, and a second foaming agent-free resin composition A step of forming a multilayer resin sheet having a laminated structure in which the second layer, the first layer, and the third layer are laminated in this order.

  Furthermore, the present invention provides a method for producing a laminated sheet according to the present invention, comprising a step of laminating a multilayer resin sheet obtained by the above method on a substrate. .

  In the method for producing a laminated sheet, in the cross-linking step of cross-linking part or all of the resin contained in the multilayer resin sheet before or during lamination on the substrate, or the resin contained in the multilayer resin sheet in the laminated sheet You may further provide the bridge | crosslinking process which bridge | crosslinks a part or all of a part. According to the laminated sheet obtained through such a crosslinking step, it is possible to suppress gas escape during foaming, and it is easy to obtain a foamed resin layer that is uniform and has little gas escape from the surface.

  Furthermore, the present invention is a method for producing a foam wallpaper comprising a base material and a foamed resin layer provided on the base material, the foaming agent contained in the first layer in the laminated sheet according to the present invention. A foamed wallpaper manufacturing method comprising a foaming step of forming a foamed resin layer by foaming a foam.

  According to the present invention, it is possible to provide a multilayer resin sheet, a laminated sheet, a production method thereof, and a production method of foamed wallpaper that can be efficiently produced by extrusion molding while having a resin layer containing a foaming agent. Can do.

It is sectional drawing which shows the lamination sheet which concerns on one Embodiment of this invention. It is sectional drawing which shows the lamination sheet which concerns on other embodiment of this invention.

[Multilayer resin sheet]
The multilayer resin sheet according to the present embodiment includes a first layer composed of a foaming agent-containing resin composition including a first resin component, a filler, and a foaming agent, and a second resin component, and includes a foaming agent. And a second layer made of a resin composition containing no foaming agent.

<Foaming agent-containing resin composition>
As the first resin component in the foaming agent-containing resin composition, a halogen-based resin such as a polyvinyl chloride resin can be used, but from the viewpoint of further reducing the influence on the environment, it may contain a non-halogen-based resin. preferable. Non-halogen resins include, for example, ethylene homopolymers, copolymers of ethylene and other olefins, polyolefin resins (single olefin polymers such as polypropylene, polybutene, polymethylpentene, etc., random of two or more olefins) Or block copolymer), styrene resin (polystyrene, acrylonitrile / styrene copolymer (AS), acrylonitrile / butadiene / styrene copolymer (ASB), etc.), ethylene copolymer (ethylene-vinyl acetate copolymer, ethylene). -Methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-methacrylic acid copolymer, etc.) Can be mentioned. These can be used alone or in combination of two or more.

  Especially, it is preferable that the 1st resin part which concerns on this embodiment contains an olefin resin, and it is more preferable that an ethylene homopolymer or a copolymer of ethylene and another olefin is included. By including an olefin-based resin, the film-forming stability during extrusion molding becomes more excellent, and the foamed cell when the foaming agent is foamed becomes finer and the foamed wallpaper has a better foamed state. A multilayer resin sheet for realizing the above can be obtained. In addition to the above, by using an ethylene homopolymer or a copolymer of ethylene and another olefin, the surface energy of the base resin is large, so that the effect of improving the ink affinity due to the reduction of bleed out is exhibited more greatly. Is done.

  An ethylene homopolymer and a copolymer of ethylene and another olefin are nonpolar non-halogen thermoplastic resins, and by using these, the increase in viscosity when the amount of filler is increased can be further suppressed. High quality wallpaper can be produced stably.

  Examples of the ethylene homopolymer include low density polyethylene synthesized by a high pressure method, high density polyethylene not containing a comonomer synthesized by a medium pressure method, and the like. Among these, low density polyethylene is preferable.

Low density polyethylene, for example, those in the density of 0.91 g / cm ³ or more 0.94 g / cm ³ or less. The density of low-density polyethylene is preferably not less density 0.91 g / cm ³ or more 0.93 g / cm ^3, more preferably less density 0.92 g / cm ³ or more 0.93 g / cm ^3. The molecular weight, melting point, melt flow rate (MFR) and the like of the low density polyethylene are not particularly limited, but the melting point is preferably 50 ° C to 140 ° C, more preferably 60 ° C to 110 ° C. If the melting point is 140 ° C. or lower, it is not necessary to melt the resin and mold it at a higher temperature, and the foaming agent is less likely to decompose during molding. On the other hand, if the melting point is 50 ° C. or higher, sufficient heat durability in actual use can be obtained. The MFR is preferably from 3 to 150, more preferably from 4 to 100. If the MFR is 3 or more, shear heat generated during molding can be suppressed, the processing temperature can be easily controlled, and there is little possibility that the foaming agent will be decomposed during molding. On the other hand, if the MFR is 150 or less, the mechanical strength of the produced foamed wallpaper is maintained, and the workability and durability are excellent.

  Examples of the low density polyethylene include Novatec LD LC802A, Novatec LD LC604, Novatec LD LJ902, Novatec LD LJ802A (above, manufactured by Nippon Polyethylene Co., Ltd.), Ube Polyethylene J2516 (produced by Ube Maruzen Polyethylene Co., Ltd.), Petrocene 202, 209, Commercial products such as (made by Tosoh Corporation) can be used.

  Examples of the copolymer of ethylene and other olefins include linear low density polyethylene, ultra-low density polyethylene, high density polyethylene obtained by copolymerization with a comonomer, and the like. Alternatively, two or more kinds can be used in combination. Among these, ultra-low density polyethylene is preferable.

The ultra low density polyethylene, for example, those in the range of less than the density 0.85 g / cm ³ or more 0.91 g / cm ^3. The density of the ultra-low density polyethylene is preferably 0.86 g / cm ³ or more and 0.90 g / cm ³ or less, more preferably 0.87 g / cm ³ or more and 0.90 g / cm ³ or less, and still more preferably 0.87 g / cm ³ or more and 0.90 g / cm ³ or less, particularly preferably 0.88 g / cm ³ or more and 0.90 g / cm ³ or less, and most preferably 0.89 g / cm ³ or more and 0.000 or less. 90 g / cm ³ or less. The molecular weight, melting point, MFR and the like of the ultra-low density polyethylene are not particularly limited, but the melting point is preferably 50 to 100 ° C, more preferably 55 to 90 ° C. If the melting point is 100 ° C. or lower, it is not necessary to melt the resin and mold it at a higher temperature, and there is little possibility that the foaming agent will decompose during molding. On the other hand, if the melting point is 50 ° C. or higher, sufficient heat durability in actual use can be obtained. The MFR is preferably from 3 to 150, more preferably from 4 to 100. If the MFR is 3 or more, shear heat generated during molding can be suppressed, the processing temperature can be easily controlled, and there is little possibility that the foaming agent will be decomposed during molding. On the other hand, if the MFR is 150 or less, the mechanical strength of the produced foamed wallpaper is maintained, and the workability and durability are excellent.

  Examples of the ultra-low density polyethylene include TAFMER DF140, DF940, DF7350 (all manufactured by Mitsui Chemicals), Kernel KJ-640T (manufactured by Nippon Polyethylene Co., Ltd.), Excellen FX CX5508 (manufactured by Sumitomo Chemical Co., Ltd.), Engage 8400. / 8407 (manufactured by Dow Chemical Co., Ltd.), Evolue P SP90100 (manufactured by Prime Polymer Co., Ltd.), LumiTac 09L54A (manufactured by Tosoh Corporation) and the like can be used.

  As linear low density polyethylene, commercial items, such as Nipolon-LM55, LM65, LM-70, LM75 (above, Tosoh Corporation make), can be used, for example.

  The non-halogen resin as the first resin component may contain a silane crosslinkable resin. Examples of the silane crosslinkable resin include a resin having a hydrolyzable silyl group. For example, a silane crosslinkable polyolefin resin or the like can be used. Examples of the silane crosslinkable polyolefin resin include a resin in which a hydrolyzable silyl group is mainly introduced into a side chain in a polyolefin polymer as a matrix. Examples of such a resin include a resin in which a hydrolyzable silyl group is mainly introduced into a side chain in a polymer such as a low density polyethylene, a high density polyethylene, an ethylene-vinyl acetate copolymer, and a polypropylene. Crosslinking is performed by hydrolysis of substituted silyl groups. In addition, the polyolefin resin which this silyl group is located in the terminal may be contained.

  Silane crosslinkable polyolefin resin is a method of random copolymerization in a container of polyolefin polymer monomer and ethylenically unsaturated silane compound, or using a peroxide in the polyolefin polymer melt. It can be obtained by a method of graft copolymerizing a silane compound. Here, the polyolefin polymer as a matrix can be used alone or in combination of two or more of the above resins. Further, the base polyolefin-based resin may be a combination of the polyolefin-based resin and a resin different from the polyolefin-based resin as long as mixing or decomposition of the resins is allowed. The degree of mixing or dispersion varies greatly depending on the type of extruder to be used, and an appropriate compatibilizer can be used. Therefore, the combined resins cannot be generally distinguished, but are preferably the same type of resins. Specific examples of the silane crosslinkable resin include “LINKLON” manufactured by Mitsubishi Chemical Corporation.

  In addition, the first resin component according to another embodiment of the present invention preferably contains an ethylene copolymer, and more preferably contains an ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer. By including an ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer, the extensional viscosity in the first layer can be ensured, so that the foam cell when foaming the foaming agent becomes finer and more A foam wallpaper having a good foaming state can be obtained.

  From the viewpoint of film formability of the multilayer resin sheet, the content of the first resin is such that the total amount of the resin is within the range of 30 to 95% by mass based on the total amount of the foaming agent-containing resin composition. Preferably, it is in the range of 35 to 90% by mass, more preferably in the range of 35 to 80% by mass, and still more preferably in the range of 45 to 70% by mass.

  The first resin component according to the present embodiment is not particularly limited as described above, and can be appropriately selected by those skilled in the art. However, low temperature molding is possible, and decomposition of the foaming agent during extrusion molding is more efficient. From the standpoint of suppression, it is preferable to include a resin having a melting point of 100 ° C. or lower. From the viewpoint of heat resistance, the first resin component according to this embodiment preferably contains a resin having a melting point of 50 ° C. or higher.

  Examples of the filler in the present embodiment include inorganic fillers and organic fillers. Examples of inorganic fillers include calcium carbonate, titanium dioxide, and hydrated metal compounds. Examples of the organic filler include melamine cyanurate, polytetrafluoroethylene (PTFE), wood flour, cellulose and derivatives thereof. These fillers can be used alone or in combination of two or more.

  Especially, it is preferable that a hydrated metal compound and calcium carbonate are included as an inorganic filler. By using a hydrated metal compound and calcium carbonate in combination as a filler, a multilayer resin sheet excellent in scratch resistance can be obtained more effectively.

  A hydrated metal compound refers to a metal compound that dehydrates by heating. Such a hydrated metal compound can release moisture by heating. Examples of the hydrated metal compound include aluminum hydroxide, magnesium hydroxide, calcium hydroxide, manganese hydroxide, iron hydroxide, zinc hydroxide, copper hydroxide and the like.

  The hydrated metal compound is preferably in the form of particles. The average particle size of the hydrated metal compound is preferably 5 μm or less, and more preferably 3 μm or less. By setting the average particle size of the hydrated metal compound to 5 μm or less, the surface area is increased and a large amount of water is dehydrated at one time. As a result, the amount of water used for the silane crosslinking reaction is increased, and crosslinking is performed more efficiently. The lower limit of the average particle size of the hydrated metal compound is preferably 0.01 μm or more, and more preferably 0.1 μm or more, from the viewpoint of suppressing an increase in viscosity. The average particle size of the hydrated metal compound is a 50% average particle size corresponding to the median value of the particle size distribution, and can be measured using, for example, a commercially available particle size distribution measuring apparatus.

  The hydrated metal compound may be subjected to various surface treatments from the viewpoint of improving dispersibility, moldability, flame retardancy, and the like. Examples of the hydrated metal compound subjected to such surface treatment include, from the viewpoint of improving dispersibility and moldability, for example, nitrate anion-treated aluminum hydroxide, high-temperature hydrothermally treated aluminum hydroxide, and the like. From the viewpoint of improving flame retardancy, for example, nitrate-treated aluminum hydroxide, zinc stannate surface-treated aluminum hydroxide, nickel compound surface-treated magnesium hydroxide, etc., phlogopite treatment, silicone treatment, silicone polymer treatment, etc. Examples include hydrated metal compounds that have been treated.

  The content of the filler is preferably 5% by mass or more based on the total amount of the foaming agent-containing resin composition, and 20% by mass or more, from the viewpoint of obtaining a foam wallpaper having excellent scratch resistance. More preferably, it is more preferably 25% by mass or more, and even more preferably 30% by mass or more. On the other hand, the upper limit of the content of the filler is preferably 60% by mass or less, and preferably 50% by mass or less, based on the total amount of the foaming agent-containing resin composition, from the viewpoint of suppressing an increase in the viscosity of the resin composition. Is more preferable, and it is still more preferable that it is 40 mass% or less.

  Examples of the filler include Softon 1000, 1200 (Bikita Powder Co., Ltd., calcium carbonate), Type CR-60, CR-60-2 (both made by Ishihara Sangyo Co., Ltd., titanium dioxide), B-303 ( Commercial products such as Sakai Kogyo Co., Ltd. (aluminum hydroxide) can be used.

  As the foaming agent according to the present embodiment, for example, a pyrolytic foaming agent can be used. Examples of the pyrolytic foaming agent include azo foaming agents such as azodicarbonamide (ADCA), azobutyronitrile, and diazoaminobenzene, hydrazide foaming agents such as p-toluenesulfonyl hydrazide, and N, N′-di. Examples thereof include nitroso-based foaming agents such as nitrosopentamethylenetetramine. Among these, ADCA is preferable because it has little toxicity, easily adjusts the foaming start temperature, and has a wide application range. These can be used alone or in combination of two or more.

  Examples of the foaming agent include VINYHALL AC # 3C-K2 (manufactured by Eiwa Kasei Co., Ltd., azodicarbonamide-based foaming agent), Cellular D (manufactured by Eiwa Kasei Co., Ltd., nitroso-based foaming agent), Neoselbon SB # 51 (Yewa Kasei). Commercial products such as a hydrazide-based foaming agent (manufactured by Corporation) can be used.

  Although content of a foaming agent is not restrict | limited in particular, It is preferable that the total amount is 1-20 mass% on the basis of the foaming agent containing resin composition whole quantity. When the content of the foaming agent is within the above range, it is possible to obtain a foamed resin layer in which gas escape from the surface due to generation of excessive gas is suppressed.

  The foaming agent-containing resin composition according to this embodiment may be colored by adding a pigment or the like as necessary. Coloring by adding a pigment may be transparent, translucent, or opaque. Examples of the pigment include inorganic pigments such as iron oxide and carbon black, and organic pigments such as aniline black and phthalocyanine blue.

  In addition, to the foaming agent-containing resin composition according to the present embodiment, known additions such as flame retardants other than fillers, foaming aids, cell regulators, stabilizers, lubricants, silane crosslinking aids, and the like are necessary. An agent can be used.

  Examples of the flame retardant other than the filler include phosphorus-based flame retardants such as phosphate esters, bromine-based flame retardants such as tetrabromobisphenol A, and the like.

  Examples of foaming aids include aliphatic systems such as stearic acid and lauric acid, fatty acid amide systems such as stearic acid amide and oleic acid amide, urea systems such as biurea, metal chlorides such as zinc chloride, and zinc oxide. A metal oxide etc. are mentioned.

  Moreover, you may use a fatty-acid metal salt as a foaming adjuvant. By including a fatty acid metal salt, a resin sheet having good foamability can be obtained.

  The fatty acid metal salt is preferably a functional group-containing fatty acid metal salt having a functional group on the carbon chain of the fatty acid metal salt. Here, the carbon chain of the fatty acid metal salt refers to a linear hydrocarbon group constituting the fatty acid. The linear hydrocarbon group may be saturated or unsaturated, and preferably has 6 to 30 carbon atoms. However, when the number of carbon atoms decreases, the melting point of the metal soap (fatty acid metal salt) decreases. The number of carbon atoms is more preferably from 10 to 24 from the viewpoint that it becomes liquid and difficult to handle, and that if the carbon chain is too long, the melting point becomes too high and the decomposability at the molding temperature decreases. Examples of fatty acids having such a hydrocarbon group include saturated fatty acids such as hexanoic acid, stearic acid, lauric acid, and behenic acid, dicarboxylic acids such as sebacic acid and azelaic acid, oleic acid, linoleic acid, and undecylenic acid. And the like, and the like.

  Examples of the functional group of the functional group-containing fatty acid metal salt include an organic group that is directly bonded to the linear hydrocarbon group. The number of functional groups is not particularly limited, and when two or more functional groups are present in the molecule, they may be the same as or different from each other.

  Examples of the functional group include a hydroxyl group, an alkyl group, a sulfonyl group (sulfonic acid ester), a phosphonyl group (phosphorous acid ester), and a trifluoromethyl group. Among these, the functional group is preferably a readily available hydroxyl group. By using the hydroxyl group-containing fatty acid metal salt, the electrical intermolecular interaction resulting from the strong polarization of the hydroxyl group works more strongly, bleed out is more effectively reduced, and printability can be further improved. In particular, when an ethylene homopolymer or a copolymer of ethylene and another olefin is combined as the resin component, the surface energy of the base resin is large, so the effect of improving ink affinity by reducing the bleed out is greater. A resin sheet or a laminated sheet can be obtained as a raw material for wallpaper that is exhibited and has good printability.

  Examples of the functional group-containing fatty acid of the functional group-containing fatty acid metal salt include 2-ethylhexanoic acid, hydroxylauric acid, hydroxystearic acid, ricinoleic acid, dihydroxystearic acid, dihydroxylauric acid and the like.

  Examples of the metal of the functional group-containing fatty acid metal salt include barium, magnesium, calcium, zinc, and the like, and are preferably at least one selected from the group consisting of magnesium, calcium, and zinc. Among these, zinc is particularly useful because it has a very strong surface-active effect and strong activity as a foaming aid.

  From the viewpoints described above, the functional group-containing fatty acid metal salt according to this embodiment includes 2-ethylhexanoic acid zinc salt, hydroxylauric acid zinc salt, hydroxystearic acid zinc salt, dihydroxystearic acid zinc salt, and dihydroxylauric acid zinc salt. A metal salt of 12-hydroxystearic acid such as zinc 12-hydroxystearate is more preferable from the viewpoint of availability and cost. These functional group-containing fatty acid metal salts can be used alone or in combination of two or more.

  As content of a foaming adjuvant, it is preferable that the total amount exists in the range of 1-100 mass parts with respect to 100 mass parts of foaming agents, and it is more within the range of 2-50 mass parts. Preferably, it is in the range of 3 to 30 parts by mass. If content of the foaming adjuvant with respect to 100 mass parts of foaming agents exists in the said range, the effect as surfactant and foaming adjuvant can fully be exhibited.

  As the cell regulator, either an organic cell regulator or an inorganic cell regulator may be used, and examples thereof include silica, phosphate ester compounds, acrylic ester resins, and methacrylic ester resins. . Commercially available products such as ADK STAB HP-10 (manufactured by ADEKA), Irgafos 38 (manufactured by BASF Japan), and JPP-2000 (manufactured by Johoku Chemical Industry Co., Ltd.) can be used as the cell regulator. it can.

  Stabilizers include, for example, radical scavengers such as phenol / amine antioxidants, hindered amine light stabilizers, peroxide decomposers such as phosphorus and sulfur, benzotriazoles, hydroxyphenyltriazines, and benzophenones. Examples include ultraviolet absorbers. From the viewpoint of suppressing discoloration, a radical scavenger or the like may be used.

  Examples of the lubricant include fatty acid-based lubricants such as stearic acid and lauric acid, fatty acid amide-based compounds such as stearic acid amide and oleic acid amide, and fatty acid metal salt-based lubricants such as zinc stearate, calcium laurate and zinc octylate. It is done.

  Examples of the silane crosslinking aid include a tin-based crosslinking aid.

<Foaming agent-free resin composition>
The foaming agent-free resin composition according to the present embodiment includes the second resin component and does not include the foaming agent.

  The 2nd resin part in a foaming agent non-containing resin composition can use the thing similar to the 1st resin part mentioned above.

  Moreover, each component (however, except a foaming agent) demonstrated in the said foaming agent containing resin composition may be included in the foaming agent non-containing resin composition which concerns on this embodiment as needed.

The multilayer resin sheet according to the present embodiment has a first layer composed of the above-described foaming agent-containing resin composition and a second layer composed of the above-described foaming agent-free resin composition, and the thickness T of the first layer. ₁ is smaller than the thickness T ₂ of the second layer. By reducing the T _1, it is possible to extrusion molding at a low temperature and low screw rotation while maintaining the line speed, to improve the production efficiency while suppressing the decomposition of the blowing agent by shear heat generation during extrusion can, furthermore, by increasing the T _2, it is possible to improve the scratch resistance in the foamed wallpaper. From such a viewpoint, T ₁ and T ₂ preferably satisfy the relationship of T ₁ × 2 ≦ T ₂ , and more preferably satisfy the relationship of T ₁ × 3 ≦ T ₂ .

The thickness of each layer constituting the multilayer resin sheet (i.e., the respective values of the T ₁ and T _2), which can be appropriately set depending on the application, for example, if the foam wallpaper application, first The thickness (T ₁ ) of the layer can be 20 to 70 μm, and the thickness (T ₂ ) of the second layer can be 40 to 140 μm. Further, from the viewpoint of economy and flame retardancy, the total thickness (T ₁ + T ₂ ) of the first layer and the second layer can be set to 60 to 210 μm. Further, a foaming, from the viewpoint of achieving both a high level and a film deposition rate in the extrusion molding, the thickness of the first layer _{(T 1)} is preferably from 20 to 50 m, 20 to 30 [mu] m is more preferable.

  In addition to the first layer and the second layer, the multilayer resin sheet according to the present embodiment includes a third resin component and a third layer made of the second foaming agent-free resin composition containing no foaming agent. May be further provided. By further providing such a third layer, the foaming agent-containing resin composition can be co-extruded with two foaming agent-free resin compositions, and the foaming agent and the die come into contact with each other. Problems that occur, for example, a phenomenon in which foreign matter adheres to the edge portion of the discharge port (so-called “eyes”) can be reduced, and productivity can be further improved. From such a viewpoint, the multilayer resin sheet according to this embodiment preferably has a laminated structure in which the second layer, the first layer, and the third layer are laminated in this order.

  The 3rd resin part in a 2nd foaming agent non-containing resin composition can use the thing similar to the 1st resin part mentioned above. From the viewpoint of further improving the adhesion to the base material to be described later, it is preferable to include ultra-low density polyethylene as the third resin component.

  In addition, the second foaming agent-free resin composition according to the present embodiment may include each component described in the foaming agent-containing resin composition (excluding the foaming agent) as necessary. Good.

The thickness T ₃ of the third layer can be set as appropriate according to the application. For example, in the case of a foam wallpaper application, the thickness (T ₃ ) of the third layer can be 1 to 20 μm. Further, from the viewpoint of economy and flame retardancy, the total of the thicknesses of the first layer, the second layer, and the third layer (T ₁ + T ₂ + T ₃ ) can be set to 60 to 230 μm.

[Method for producing multilayer resin sheet]
The multilayer resin sheet according to the present embodiment can be obtained by extruding the foaming agent-containing resin composition and the foaming agent-free resin composition described above, and optionally the second foaming agent-free resin composition. it can.

  There is no restriction | limiting in particular as the method of extrusion molding, For example, you may form a 1st layer and a 2nd layer by extruding the said foaming agent containing resin composition and a foaming agent non-containing resin composition, respectively. The first layer and the second layer may be formed by coextrusion molding at least the foaming agent-containing resin composition and the foaming agent-free resin composition. When the first layer and the second layer are formed by extruding the foaming agent-containing resin composition and the foaming agent-free resin composition, respectively, the first layer and the second layer are laminated to form a multilayer. A resin sheet can be manufactured.

  In the multilayer resin sheet further comprising the third layer, for example, by extruding the foaming agent-free resin composition, the foaming agent-containing resin composition, and the second foaming agent-free resin composition, respectively, Two layers, a first layer, and a third layer may be formed, or by coextrusion molding a foaming agent-free resin composition, a foaming agent-containing resin composition, and a second foaming agent-free resin composition A multilayer resin sheet having a laminated structure in which the second layer, the first layer, and the third layer are laminated in this order may be formed. Furthermore, the second layer and the first layer are obtained by co-extrusion molding the foaming agent-free resin composition and the foaming agent-containing resin composition, and by extruding the second foaming agent-free resin composition. And the third layer may be formed, or the foaming agent-containing resin composition and the second foaming agent-free resin composition are coextruded, and separately, the foaming agent-free resin composition is extruded. Thus, the second layer, the first layer, and the third layer may be formed.

  When the second layer, the first layer, and the third layer are formed by extruding the foaming agent-free resin composition, the foaming agent-containing resin composition, and the second foaming agent-free resin composition, respectively. A multilayer resin sheet can be produced by laminating the second layer, the first layer, and the third layer in this order.

  Examples of the coextrusion molding method include a coextrusion method such as a T die extrusion method, a T die extrusion simultaneous lamination method, and a T die extrusion tandem lamination method.

  Specifically, for example, when co-extrusion molding of a foaming agent-containing resin composition and a foaming agent-free resin composition, the foaming agent-containing resin composition and the foaming agent-free resin composition are respectively separated into separate extruders (for example, A single-screw extruder, a twin-screw extruder, etc.), and after melting and kneading and dispersing them in a feed block type, a sheet is formed with a T-die, and a first composition comprising a foaming agent-containing resin composition Examples thereof include a method of obtaining a resin sheet comprising two layers of a second layer comprising a layer and a foaming agent-free resin composition.

  As the conditions for extrusion molding with a T-die, the extrusion temperature is preferably 140 ° C. or lower, more preferably 135 ° C. or lower, from the viewpoint of setting the melting point of the resin component or higher while suppressing decomposition of the foaming agent component. More preferably, the temperature is 130 ° C. or lower. Moreover, extrusion temperature can be made into melting | fusing point +10 degreeC or more of resin with the highest melting | fusing point. Thereby, it can suppress that resin is extruded in an unmelted state.

  The first layer in the multilayer resin sheet may be subjected to a crosslinking treatment. Examples of the crosslinking treatment include heat treatment such as electron beam irradiation treatment and superheated steam treatment. When the foaming agent-containing resin composition contains a silane crosslinkable resin, superheated steam treatment and water crosslinking treatment can be performed. In this case, the first layer can be cross-linked while being laminated with other layers.

  In the electron beam irradiation treatment, for example, the multilayer resin sheet can be crosslinked by irradiating an electron beam from one side or both sides of the molded multilayer resin sheet. Although the electron beam irradiation conditions depend on the thickness of the resin layer, an acceleration voltage of 150 to 300 kV and an irradiation dose of 10 to 100 kGy are preferable. If the acceleration voltage is within the above range, the electron beam can be sufficiently reached deep in the thickness direction of the resin sheet, and deterioration due to the electron beam on the backing paper can be suppressed. Moreover, if irradiation dose is in the said range, it will become easy to give desired bridge | crosslinking to a resin sheet, suppressing the yellowing of a resin sheet and the change of a mechanical physical property.

  Examples of the superheated steam treatment include a method in which superheated steam (also referred to as superheated steam) is treated for 20 seconds to 15 minutes in an environment of 130 ° C. to 280 ° C. The superheated steam treatment includes, for example, a method in which a sheet-like material is arranged in a superheated steam atmosphere and the superheated steam is brought into contact with the sheet-like material. Moreover, as a method of water-crosslinking, there is a method of water-crosslinking by curing for 1 day to 1 month in a temperature range of 40 ° C. to 70 ° C. in an environment with a humidity of 60% or more. There is a method of curing and hydrocrosslinking in an environment of a 90% constant temperature and humidity chamber.

[Laminated sheet]
The laminated sheet according to the present embodiment includes a base material and the multilayer resin sheet provided on the base material.

FIG. 1 is a cross-sectional view showing a laminated sheet according to an embodiment of the present invention. As shown in FIG. 1, the laminated sheet 10 according to this embodiment includes a base material 3 and a multilayer resin sheet 4 a provided on the base material 3. The multilayer resin sheet 4a includes a first layer 1 composed of a foaming agent-containing resin composition including a first resin component, a filler, and a foaming agent, and a second resin component, and does not include a foaming agent. And a second layer 2 made of a resin composition not containing a foaming agent, provided on the substrate 3 via the first layer 1, and the thickness T ₁ of the first layer 1 is the thickness of the second layer 2. smaller than T _2.

FIG. 2 is a cross-sectional view showing a laminated sheet according to another embodiment of the present invention. As shown in FIG. 2, the laminated sheet 20 according to this embodiment includes a base material 3 and a multilayer resin sheet 4 b provided on the base material 3. The multilayer resin sheet 4b includes a first layer 1 composed of a foaming agent-containing resin composition including a first resin component, a filler, and a foaming agent, and a second resin component, and does not include a foaming agent. The third layer 5 has a second layer 2 made of a foaming agent-free resin composition, and a third layer 5 made of a foaming agent-free resin composition containing a third resin component and no foaming agent. The thickness T ₁ of the first layer 1 is smaller than the thickness T ₂ of the second layer 2. The thickness T ₃ of the third layer 5 is not particularly limited, it can range exemplified in the description of the multilayer resin sheet.

The base material is not particularly limited as long as it is usually used as a paper base material such as a conventional backing paper for foam wallpaper. As such a substrate, for example, a pulp-based flame retardant paper impregnated with a water-soluble flame retardant such as guanidine sulfamate or guanidine phosphate, or an inorganic agent such as magnesium carbonate, aluminum hydroxide, magnesium hydroxide or the like. Examples include mixed paper. These weighings may be 50 to 300 g / m ² or 60 to 160 g / m ² .

  In addition, from the viewpoint of improving the adhesion between the base material and the multilayer resin sheet, the surface of the base material on the side where the multilayer resin sheet is provided is easily adhered, for example, by corona discharge treatment, plasma treatment, ozone treatment, etc. You may give a process and may provide the easily bonding process layer formed from the acrylic-butyl copolymer, the polyurethane which consists of isocyanate and a polyol.

[Production method of laminated sheet]
The laminated sheet according to the present embodiment includes, for example, a step of laminating a multilayer resin sheet obtained by the above method on a base material. From the viewpoint of more effectively obtaining the effects of the present invention, the laminated sheet preferably includes a step of laminating the first layer in the multilayer resin sheet on the substrate.

  The laminating method is not particularly limited, and examples thereof include a method in which a multilayer resin sheet and a substrate are subjected to thermocompression bonding using a hot press machine, a method in which pressure bonding is performed using superheated steam, and the like. . According to the method of pressure bonding using superheated steam, it becomes possible to laminate onto the base material while maintaining the molten state of the surface of the sheet-like material with superheated steam, and the surface of the base material to be adhered by the leveling effect Can be prevented from being transferred to the multilayer resin sheet. Moreover, when the 1st layer in a multilayer resin sheet contains a silane crosslinkable resin, a silane crosslinkable resin can be bridge | crosslinked efficiently with superheated steam.

  The manufacturing method of the lamination sheet which concerns on embodiment forms a 1st layer and a 2nd layer by extruding the said foaming agent containing resin composition and a foaming agent non-containing resin composition, respectively, for example, the said 2nd After laminating the layer on the base material, a step of laminating the first layer on the surface of the second layer opposite to the base material may be provided.

  Further, when the third layer is provided, for example, after laminating the third layer on the base material, the first layer is laminated on the surface of the third layer opposite to the base material side, and You may provide the process of laminating the 2nd layer on the surface on the opposite side to the 3rd layer side of the 1st layer concerned. In addition, after laminating the third layer on the base material, laminating the first layer side of the laminate having the first layer and the second layer on the surface of the third layer opposite to the base material side Or after laminating the third layer side of the laminate having the first layer and the third layer onto the substrate, the second layer is opposite to the substrate side of the first layer. A step of laminating on the surface may be provided.

  The method for producing a laminated sheet according to the present embodiment includes a cross-linking step of cross-linking part or all of the resin contained in the multi-layer resin sheet before or during lamination on the substrate, or the multi-layer resin sheet in the multi-layer sheet A cross-linking step of cross-linking part or all of the resin component contained in the resin may be further provided. The crosslinking treatment can be the same as the method described in the method for producing the multilayer resin sheet. When the multilayer resin sheet contains a silane crosslinkable resin, lamination and crosslinking of the silane crosslinkable resin can be performed simultaneously with superheated steam.

[Method for producing foam wallpaper]
The foam wallpaper according to the present embodiment includes a base material and a foamed resin layer provided on the base material. Such foamed wallpaper can be obtained by a method for producing foamed wallpaper, which includes a foaming step of forming a foamed resin layer by foaming the foaming agent contained in the first layer in the laminated sheet.

  Foaming of the foaming agent can be performed by heating the multilayer resin sheet. The heating condition can be appropriately set depending on the components constituting the multilayer resin sheet, and is not particularly limited, but is preferably heated at 160 ° C. to 280 ° C. for 10 seconds to 120 seconds, and at 220 ° C. to 240 ° C. Heating for 20 to 40 seconds is more preferable, and heating at 220 ° C. for 40 seconds is more preferable.

  The method for producing foamed wallpaper according to the present embodiment includes a cross-linking step of cross-linking part or all of the resin contained in the multi-layer resin sheet before being laminated on the substrate, or a multi-layer resin sheet in a laminated sheet A cross-linking step of cross-linking part or all of the resin component contained in the resin may be further provided. The crosslinking treatment can be the same as the method described in the method for producing the multilayer resin sheet. When the resin sheet contains a silane crosslinkable resin, lamination and crosslinking of the silane crosslinkable resin can be performed simultaneously with superheated steam.

  Furthermore, in the manufacturing method of the foam wallpaper which concerns on this embodiment, the uneven | corrugated shape formation process which provides an uneven | corrugated shape in the surface on the opposite side to the base material of the said 2nd layer may be provided. An uneven | corrugated shape formation process can be equipped after the said foaming process, for example. The method of providing the uneven shape is not particularly limited. For example, by using heat at the time of superheated foaming, the surface side is a cooling embossing roll, the base material side is a rubber roll, Examples of the method include forming a concavo-convex shape on the surface by niping (embossing) and cooling. The uneven shape is not particularly limited, and examples thereof include a wood grain plate conduit groove, a stone plate surface unevenness, a cloth surface texturer, a satin texture, a grain texture, a hairline, and a single line groove. These can be appropriately selected according to the purpose, and a plurality of them may be combined.

  The method for producing foam wallpaper according to the present embodiment may include a printing step of providing a pattern layer and a surface protective layer. The pattern layer and the surface protective layer can be appropriately provided using known materials. If the object of the present invention can be achieved, the pattern layer and the surface protective layer may not be provided. The pattern layer and the surface protective layer can be provided using a known printing technique such as gravure coating. In addition, a printing process can be provided before the said foaming process, for example. That is, the pattern layer and the surface protective layer can be provided before foaming the foaming agent.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. However, the present invention is not limited to the following examples.

[Foaming agent-containing resin composition]
Using the same-direction meshing twin screw extruder, pellets of the foaming agent-containing resin composition were prepared with the formulation shown in Table 1 while controlling the resin temperature at 120 ° C. so that the foaming agent was not decomposed.

  The following materials were used for each component shown in Table 1.

[Low density polyethylene]
Resin A: Novatec LD LJ802A (manufactured by Nippon Polyethylene Co., Ltd., trade name, melting point = 107 ° C., MFR = 27 (190 ° C.), density = 0.919 g / cm ³ )

[Ultra low density polyethylene]
Resin B: Kernel KJ-640T (manufactured by Nippon Polyethylene Co., Ltd., trade name, melting point = 58 ° C., MFR = 30 (190 ° C.), density = 0.85 g / cm ³ )

[Ethylene vinyl acetate copolymer]
Resin C: Evaflex EV150 (Mitsui DuPont Polychemical Co., Ltd., trade name, melting point = 61 ° C., MFR = 30 (190 ° C.), density = 0.960 g / cm ³ )

[Ethylene ethyl acrylate copolymer]
Resin D: Lexpearl EEA A6200 (manufactured by Nippon Polyethylene Co., Ltd., trade name, melting point = 94 ° C., MFR = 20 (190 ° C.))

[Silane crosslinkable resin]
Resin E: Linkron SS732N (Mitsubishi Chemical Corporation, trade name, melting point = 58 ° C., MFR = 13 (190 ° C.), density = 0.85 g / cm ³ )

[Calcium carbonate]
Filler A: Softon 1000 (Bihoku Powder Chemical Co., Ltd., trade name)

[titanium dioxide]
Filler B: Taipei CR-60-2 (Ishihara Sangyo Co., Ltd., trade name)

Foaming agent: VINYHALL AC # 3C-K2 (manufactured by Eiwa Kasei Kogyo Co., Ltd., trade name, azodicarbonamide foaming agent)

Foaming aid: Zn-St (Nitto Kasei Kogyo Co., Ltd., trade name, zinc stearate)

Silane crosslinking aid: Linkron LZ013 (Mitsubishi Chemical Corporation, trade name, polyethylene base)

[Foaming agent-free resin composition]
Using the same direction meshing type twin screw extruder, pellets of the foaming agent-free resin composition were prepared with the formulation shown in Table 2 while controlling the resin temperature at 120 ° C.

[Second foaming agent-free resin composition]
The resin B was pelletized with a second foaming agent-free resin composition while the resin temperature was controlled at 120 ° C. using the same-direction meshing twin-screw extruder.

[Production of foam wallpaper]
(Examples 1-7, Comparative Examples 1-2)
The pellets of the foaming agent-containing resin compositions 1 to 6 prepared above, the pellets of the foaming agent-free resin compositions 7 to 8 and the pellets of the second foaming agent-free resin composition are used in combinations shown in Table 3. Thus, a multilayer resin sheet was produced. Specifically, pellets of the foaming agent-free resin composition were prepared using a screw 1 (screw diameter (D) 65 mm, L / D (screw length divided by screw diameter) = 28 single screw extruder). Extruding and extruding pellets of the foaming agent-containing resin composition using a screw 2 (single screw extruder with screw diameter (D) 50 mm, L / D = 28). In Examples 2-6 and Comparative Examples 1-2 Furthermore, the pellets of the second foaming agent-free resin composition were extruded using a screw 3 (single screw extruder with a screw diameter (D) of 50 mm and L / D = 28), and each was joined in a feed block type. Later, a sheet was formed with a T die having a width of 700 mm at a line speed of 20 m / min, a second layer composed of a foaming agent-free resin composition, a first layer composed of a foaming agent-containing resin composition, and Examples 2 to 2 6 and Comparative Example 1 A third layer further comprises a second blowing agent-containing resin composition in 2 to obtain a multi-layer resin sheet made of. The thickness of each layer was as shown in Table 3, respectively. Moreover, the temperature setting value of extrusion molding was set to 100 ° C. only for the screw 2 in Examples 4 to 6, and was set to 120 ° C. otherwise.

Next, the multilayer resin sheet formed as described above was placed on the backing paper (KJ Special Paper, WK-6651HT, weight 65 g / m ² ), and heated at 110 ° C. with a press pressure of 5 MPa. The laminate sheet was obtained by pressing for a minute and heat-sealing.

Furthermore, after the corona discharge treatment was applied to the surface on the second layer side, a pattern was printed at 1 g / m ² using a water-based ink (manufactured by Dainichi Seika Kogyo Co., Ltd., Hydrick WP) with a gravure printing machine. A matte surface coating agent (Nissin Chemical Industry Co., Ltd., Viniblanc 890) was applied at 2 g / m ² using a coating machine (manufactured by Kurashiki Boseki Co., Ltd., GP-10) to prepare a raw material before cross-linking.

  In Examples 1-2, 4-7, and Comparative Examples 1-2, the resulting pre-crosslinking raw material was irradiated with an electron beam at an acceleration voltage of 180 kV and an irradiation dose of 70 kGy, respectively, and the resin content was crosslinked. Heating was performed in an oven at 220 ° C. for 40 seconds to foam the foaming agent to produce a foamed wallpaper.

  In Example 3, after curing for 72 hours in a constant temperature and humidity chamber at a temperature of 40 ° C. and a relative humidity of 90% RH, the silane crosslinkable resin was crosslinked, and then heated in an oven at 220 ° C. for 40 seconds to obtain a foaming agent. To make a foam wallpaper.

[Evaluation of multilayer resin sheet]
(Film formation stability)
About the multilayer resin sheet produced in Examples 1-7 and Comparative Examples 1-2, film forming stability was confirmed visually. In the evaluation, “A” indicates that fine foaming is not recognized in the first layer, and “B” indicates that fine foaming is recognized. The results are shown in Table 3.

[Evaluation of foam wallpaper]
The foamed wallpaper thus produced was evaluated for foaming magnification, foamed cell shape and scratch resistance according to the following methods.

(Foaming ratio)
The thickness of the foamed wallpaper was measured at 20 points with a thickness meter, the thickness of the backing paper (100 μm) was subtracted from the average value, and the value divided by the thickness of the resin sheet before foaming was calculated as the foaming ratio. The results are shown in Table 3.

(Foam cell shape)
The short diameter of the foam cell was measured, and the foam cell shape was evaluated according to the following criteria. If it is AA, A, or B, it can be evaluated that foamability is favorable. The results are shown in Table 3.
AA: The minor axis of the elliptical foam cell is generally less than 200 μm.
A: The minor axis of the elliptical foam cell is approximately 200 μm or more and less than 300 μm.
B: The minor axis of the elliptical foam cell is approximately 300 μm or more and less than 700 μm.
C: The minor axis of the elliptical foam cell is approximately 700 μm or more.

(Scratch resistance)
The scratch resistance was evaluated using a Coins scratch tester. Specifically, the foamed wallpaper was placed on a horizontal surface, and the surface state was observed by scratching the foamed wallpaper with a load of 600 g at a 45 ° angle using a 10-yen coin. The scratch resistance was evaluated based on the following criteria. If it is A or B, it can be evaluated that the scratch resistance is sufficient. The results are shown in Table 3. In addition, when the part from which evaluation differs in the same sample coexists, it described with AB, BC, etc.
A: No scratch on the surface of the specimen.
B: Slight scratches remain on the surface.
C: Scratches enter the foam layer.

  DESCRIPTION OF SYMBOLS 1 ... 1st layer, 2 ... 2nd layer, 3 ... Base material, 4a, 4b ... Multilayer resin sheet, 5 ... 3rd layer, 10, 20 ... Laminated sheet.

Claims (12)

The 1st layer which consists of a foaming agent containing resin composition containing the 1st resin part, a filler, and a foaming agent, The foaming agent non-containing resin composition which contains the 2nd resin part, and does not contain a foaming agent A multilayer resin sheet having a second layer comprising:
The thickness T ₁ of the first layer is smaller than the thickness T ₂ of the second layer, the multilayer resin sheet. The multilayer resin sheet according to claim 1, wherein T ₁ and T ₂ satisfy a relationship of T ₁ × 2 ≦ T ₂ .   The multilayer resin sheet of Claim 1 or 2 further provided with the 3rd layer which consists of a 2nd foaming agent non-containing resin composition which contains a 3rd resin part and does not contain a foaming agent.   The multilayer resin sheet according to any one of claims 1 to 3, wherein the first resin component includes a resin having a melting point of 100 ° C or lower.   The multilayer resin sheet according to claim 4, wherein the resin is an ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer.   The multilayer resin sheet according to any one of claims 1 to 4, wherein the first resin component includes a silane crosslinkable resin.   A laminated sheet comprising: a base material; and the multilayer resin sheet according to any one of claims 1 to 6 provided on the base material. It is a manufacturing method of the multilayer resin sheet according to any one of claims 1 to 6,
The step of forming the first layer and the second layer by extruding the foaming agent-containing resin composition and the foaming agent-free resin composition, respectively, or at least the foaming agent-containing resin composition and the foaming Forming the first layer and the second layer by co-extrusion of an agent-free resin composition;
A method for producing a multilayer resin sheet. The multilayer resin sheet further comprises a third layer comprising a second foaming agent-free resin composition containing a third resin component and not containing a foaming agent;
By coextruding at least the foaming agent-free resin composition, the foaming agent-containing resin composition, and the second foaming agent-free resin composition, the second layer, the first layer, and the third layer Forming the multilayer resin sheet having a laminated structure in which layers are laminated in this order;
The manufacturing method of the multilayer resin sheet of Claim 8 provided with these. It is a manufacturing method of the lamination sheet according to claim 7,
The manufacturing method of a lamination sheet provided with the process of laminating the multilayer resin sheet obtained by the method of Claim 8 or 9 on a base material.   A crosslinking step of crosslinking a part or all of the resin contained in the multilayer resin sheet before or during lamination on the substrate, or the resin content contained in the multilayer resin sheet in the laminated sheet The manufacturing method of the lamination sheet of Claim 10 further equipped with the bridge | crosslinking process which bridge | crosslinks part or all. A foamed wallpaper manufacturing method comprising: a base material; and a foamed resin layer provided on the base material,
A method for producing foamed wallpaper, comprising a foaming step of forming a foamed resin layer by foaming the foaming agent contained in the first layer in the laminated sheet according to claim 7.

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