JP2016216672A - Resin composition, resin sheet, laminate sheet and foam wall paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition having good foamability and sufficient printability and hardly generating discoloration in a foaming process, a resin sheet, a laminate sheet and a foam wall paper.SOLUTION: There is provided a resin composition for forming a foam resin layer of a foam wall paper having a substrate and the foam resin layer arranged on the substrate, the resin composition containing a filler, a foaming agent, a foaming auxiliary, and a resin component, where the foaming auxiliary contains a functional group-containing aliphatic acid metal salt having a functional group containing an active proton in a carbon chain of the aliphatic acid metal salt and carboxylic acid hydrazide. There are also provided a resin sheet, a laminate sheet and a foam wall paper using the resin composition.SELECTED DRAWING: None

Description

  The present invention relates to a resin composition, a resin sheet, a laminated sheet, and foamed wallpaper. More specifically, the present invention relates to a foam wallpaper that can be used for decorating a wall of a building such as a detached house, an apartment house, a store, or an office building, and a resin composition, resin sheet, and laminated sheet used therefor.

  As wallpaper used for wall decoration of buildings, etc., vinyl chloride wallpaper in which a resin layer of vinyl chloride resin is provided on a paper base material is widely used. In recent years, in consideration of the environment, a halogen-free resin such as an ethylene-vinyl acetate copolymer has been used (for example, see Patent Documents 1 and 2 below).

  As a method for producing such foamed wallpaper, a resin composition containing a foaming agent is melt-extruded and laminated on a base material, or is separately sheeted by a T-die extrusion method, and later applied to dry lamination or heat lamination. After laminating the base material to obtain a laminated sheet with a resin sheet provided on the base material, the resin sheet with the surface printed thereon is heated as necessary to decompose and foam the foaming agent. There is a way to make it.

  In foamed wallpaper of a type to which such a thermal decomposition type foaming agent is added, it is known that a fatty acid metal salt is used as a foaming aid for the purpose of accelerating the decomposition of the foaming agent and adjusting the decomposition temperature. For example, Patent Document 3 discloses that zinc stearate and zinc octylate are used as foaming aids.

Japanese Patent Laid-Open No. 6-47875 JP 2001-347611 A JP 2010-228416 A

  By the way, it is common to provide a printing layer on the surface of the foam wallpaper for decoration. However, the resin sheet for foamed wallpaper in which the above-mentioned fatty acid metal salt is blended so as to obtain a high foaming ratio is used when the product is printed on the surface. The printability of the ink sometimes deteriorated.

  In order to solve the above problems, the present inventors have found that the use of a fatty acid metal salt having a functional group in the carbon chain can effectively suppress the decrease in adhesion due to the bleed out. However, as a result of further studies by the present inventors, it has been found that the resin may change color during the foaming process of the wallpaper when a specific functional group is selected.

  The present invention has been made in view of the above circumstances, and has a resin composition, a resin sheet, a laminated sheet, and a foam having good foamability and sufficient printability and hardly causing discoloration in the foaming process. The purpose is to provide wallpaper.

  That is, the present invention is a resin composition for forming a foamed resin layer of a foam wallpaper comprising a base material and a foamed resin layer provided on the base material, the filler, the foaming agent, A foaming aid and a resin component, and the foaming aid comprises a functional group-containing fatty acid metal salt having a functional group containing an active proton in the carbon chain of the fatty acid metal salt, and a carboxylic acid hydrazide. A composition is provided.

  According to the resin composition of the present invention, it is possible to form a resin sheet that has good foamability and sufficient printability and is unlikely to cause discoloration during the foaming process. The present inventors infer the reason why such an effect is obtained as follows.

  First, as a factor that decreases the printability of a resin sheet containing a conventional fatty acid metal salt, the surfactant activity of the fatty acid metal salt is very strong, and bleeds out to the surface on which printing is performed or the printing interface after printing. It is conceivable that the fatty acid metal salt decreases the wettability of the surface and the ink affinity, or decreases the adhesion of the ink. On the other hand, in the present invention, by using the functional group-containing fatty acid metal salt as a foaming aid, a functional group containing an active proton added to the carbon chain of the fatty acid metal salt is obtained while obtaining good foamability. The present inventors consider that the printability is maintained because the bleed-out to the surface on which printing is performed or the printing interface after printing can be reduced by interacting with the surrounding resin.

  On the other hand, as described above, the present inventors have found that when the functional group-containing fatty acid metal salt is used as a foaming aid, the resulting foamed wallpaper may be discolored. This is considered to be due to the fact that the active protons in the system interact with the foaming agent to change the decomposition process and generate a colored substance. On the other hand, in the present invention, by using a functional group-containing fatty acid metal salt and a carboxylic acid hydrazide as a foaming aid, active protons that interact with the foaming agent are captured by the carboxylic acid hydrazide, thereby generating a colored substance. The present inventors consider that it was possible to suppress the discoloration of the resulting foamed wallpaper.

  By the way, in recent years, water-based inks have been used for printed layers of foamed wallpaper used in houses due to increasing consumer awareness of chemical substances. However, these water-based inks are difficult to ensure adhesion because of their low affinity for resins. Since the conventional fatty acid metal salt has a strong surface-active effect, when the bleed-out occurs on the surface of the foam wallpaper, the ink adhesion may be remarkably lowered.

  On the other hand, according to the resin composition of the present invention, bleeding out to the surface of the foamed wallpaper is unlikely to occur, so that sufficient ink adhesion can be ensured even with water-based ink.

  In addition, according to the resin composition of the present invention, for example, a sufficient non-foaming layer is provided on the surface of the laminated sheet to ensure sufficient printability without requiring treatment such as blocking the bleeding out of the foaming aid. Therefore, a resin sheet having both sufficient printability and good foamability can be formed with a simpler sheet structure.

  The carboxylic acid hydrazide is preferably carboxylic acid dihydrazide. By using a carboxylic acid dihydrazide having two hydrazide groups in the molecule, it is possible to more efficiently capture active protons and more efficiently suppress the generation of a colored substance.

  It is preferable that content of the said carboxylic acid hydrazide is 0.1-7 mass parts with respect to 100 mass parts of resin parts. By setting the content of the carboxylic acid hydrazide within the above range, it is possible to more efficiently suppress the generation of a colored substance in the foaming step while restricting the bleed out due to the carboxylic acid hydrazide.

  The content of the carboxylic acid hydrazide is preferably 30 to 100 parts by mass with respect to 100 parts by mass of the functional group-containing fatty acid metal salt. By setting the content of carboxylic acid hydrazide in the above range, it is possible to more efficiently suppress the coloration after foaming without excessively lowering the foaming temperature during the production of foamed wallpaper, and to maintain good printability. .

  The functional group is preferably a hydroxyl group. By using a hydroxyl group-containing fatty acid metal salt having a hydroxyl group in the carbon chain of the fatty acid metal salt, the foamability and printability of the resin composition are compatible at a high level, and at the same time, the generation of colored substances in the foaming process is more efficient. Can be suppressed. The reason why such an effect can be obtained is that, since a hydroxyl group has a low acid dissociation constant as a functional group having an active proton, generation of a colored substance can be further suppressed by suppressing the active proton concentration in the system. In addition, it is conceivable that the electrical intermolecular interaction resulting from the strong polarization as compared with the carbon-hydrogen bond works more strongly and bleed out can be reduced more effectively.

The resin component preferably contains at least a density of 0.91 g / cm ³ or more 0.94 g / cm ³ or less of low density polyethylene. By using such a resin component, the flexibility of the resin can be improved, and it becomes easy to realize a foamed wallpaper having a foamed resin layer in a good foamed state and excellent in workability.

The resin component, in addition to the low density polyethylene described above, may further include an ultra low density polyethylene density of less than 0.88 g / cm ³ or more 0.91 g / cm ^3. By using such a resin component, the flexibility of the resin can be further improved, and it is easier to realize a foamed wallpaper having a foamed resin layer in a good foamed state and excellent in workability. Become.

  The present invention also provides a resin sheet obtained by extrusion film formation of the resin composition according to the present invention. This resin sheet may be subjected to a crosslinking treatment. Thereby, the gas escape at the time of foaming can be suppressed, and the foamed resin layer with little gas escape from the surface can be obtained.

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

  The present invention is also a foam wallpaper comprising a base material and a foamed resin layer provided on the base material, wherein the foaming agent contained in the resin sheet in the laminated sheet according to the present invention is foamed. The resulting foamed wallpaper is provided.

  According to the present invention, it is possible to provide a resin composition, a resin sheet, a laminated sheet, and a foamed wallpaper that have good foamability and sufficient printability and are less likely to be discolored during the foaming process.

[Resin composition]
The resin composition according to the present embodiment is a resin composition for forming a foamed resin layer of a foamed wallpaper comprising a base material and a foamed resin layer provided on the base material, and a filler, A foaming agent, a foaming aid, and a resin component.

  Examples of the filler in the present embodiment include inorganic fillers and organic fillers. Examples of the inorganic filler include calcium carbonate and titanium dioxide. 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.

  The content of the filler is not particularly limited, but the total amount is preferably 10 to 60% by mass based on the total amount of the resin composition. Reasons for adding the filler include securing the concealment property of the foam wallpaper, reducing the calorie burn per unit area, and reducing the production cost due to the increase in volume. When the content of the filler (especially inorganic filler) is 20 to 40% by mass based on the total amount of the resin composition, low production of foam wallpaper with low combustion calories while ensuring good concealment as a foam wallpaper. Can be manufactured at cost.

  As the filler, for example, commercially available products such as Softon 1000 (Calcium Carbonate, manufactured by Bihoku Powder Co., Ltd.), and Taipei CR-60-2 (Titanium Dioxide, manufactured by Ishihara Sangyo Co., Ltd.) 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 Co., Ltd.) 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 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 auxiliary agent according to this embodiment includes a functional group-containing fatty acid metal salt having a functional group containing an active proton in the carbon chain of the fatty acid metal salt, and a carboxylic acid hydrazide. 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 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 the fatty acid having 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.

  Here, the functional group containing an active proton includes those having an acid dissociation constant of 18 or less in water at 25 ° C. among organic groups directly bonded to the linear hydrocarbon group. The lower limit of the acid dissociation constant is not particularly limited, but may be 9 or more from the viewpoint of acid degradation of the resin, aggregation / acid modification of the filler, and general use as wallpaper. The number of the functional groups in the same molecule is not particularly limited, and when two or more functional groups are present, these may be the same or different.

  Examples of the functional group include a hydroxyl group, a nitromethyl group, a mercapto group, and the like. Among these, the functional group is preferably a readily available hydroxyl group. By using a hydroxyl group-containing fatty acid metal salt, electrical intermolecular interaction due to strong polarization of the hydroxyl group works more strongly, bleedout is reduced more effectively, and foamability and printability are further improved. Can be compatible. In particular, when combined with an ethylene homopolymer or a copolymer of ethylene and another olefin as the resin component, there is a difference in the surface energy of the base resin, so there is an effect of improving ink affinity by reducing bleed out. It is possible to obtain a resin sheet or a laminated sheet as a wallpaper material that is more greatly exhibited and has good printability. Furthermore, since a hydroxyl group has a low acid dissociation constant as a functional group having an active proton, generation of a colored substance can be further suppressed by suppressing the active proton concentration in the system.

  Examples of the functional group-containing fatty acid of the functional group-containing fatty acid metal salt include 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. Among them, zinc is particularly useful because it has very strong activity as a foaming aid.

  The functional group-containing fatty acid metal salt according to the present embodiment is preferably a hydroxylauric acid zinc salt, a hydroxystearic acid zinc salt, a dihydroxystearic acid zinc salt, or a dihydroxylauric acid zinc salt from the viewpoints described above. From this point of view, zinc 12-hydroxystearate is more preferable. Moreover, these functional group containing fatty acid metal salts can be used individually by 1 type or in combination of 2 or more types.

  As content of the functional group containing fatty acid metal salt which concerns on this embodiment, it is preferable to exist in the range of 1-10 mass parts with respect to 100 mass parts of resin parts, and it exists in the range of 1-7 mass parts. It is more preferable. When the content is in the range of 1 to 10 parts by mass with respect to 100 parts by mass of the resin content, a resin composition having better printability can be obtained. When the content is less than 1 part by mass, the effect as a foaming aid of the functional group-containing fatty acid metal salt is not sufficiently obtained, and the decomposition efficiency of the foaming agent tends to decrease, and when the content is more than 10 parts by mass. The printability tends to decrease due to the influence of the functional group-containing fatty acid metal salt present on the surface of the resin sheet formed into a film.

  The carboxylic acid hydrazide in the present embodiment refers to a compound produced by allowing a hydrazine compound to act on a carboxylic acid or a derivative thereof. The number of hydrazide groups in the molecule of carboxylic acid hydrazide is not particularly limited, but if the number of hydrazide groups is too small, a larger amount of carboxylic acid hydrazide is required to capture active protons, while the number of hydrazide groups When there is too much, the polarity, melting | fusing point, viscosity, etc. of carboxylic acid hydrazide itself will increase, and compatibility with base resin will fall. From such a viewpoint, the number of hydrazide groups in the molecule of the carboxylic acid hydrazide is preferably 1 to 3, and more preferably 2.

  The carboxylic acid hydrazide in the present embodiment is derived from, for example, a carboxylic acid monohydrazide derived from a monocarboxylic acid such as stearic acid, benzoic acid or caprylic acid, or a dicarboxylic acid such as succinic acid, terephthalic acid or adipic acid. And trivalent or higher carboxylic acid hydrazides derived from trivalent or higher carboxylic acids such as carboxylic acid dihydrazide, trimesic acid and ethylenediaminetetraacetic acid. These can be appropriately selected depending on the viscosity, melting point, polarity, etc. of the base resin, but in view of the number of preferred hydrazide groups mentioned above and the purchase cost, etc., it consists of 4-methylbenzoic acid hydrazide, adipic acid dihydrazide and succinic acid dihydrazide. It is preferable to use at least one selected from the group.

  As content of carboxylic acid hydrazide which concerns on this embodiment, it is preferable to exist in the range of 0.1-7 mass parts with respect to 100 mass parts of said resin parts, and being in the range of 2-5 mass parts. Is more preferable. If the content of the carboxylic acid hydrazide is within the range of 0.1 to 7 parts by mass with respect to 100 parts by mass of the resin component, the generation of the colored substance in the foaming process is limited while restricting the bleed out by the carboxylic acid hydrazide. It can be suppressed more efficiently.

  Moreover, as content of carboxylic acid hydrazide which concerns on this embodiment, it is preferable to exist in the range of 30-100 mass parts with respect to 100 mass parts of functional group containing fatty acid metal salts, and within the range of 50-100 mass parts. It is more preferable that When the content of the carboxylic acid hydrazide is within a range of 30 to 100 parts by mass with respect to 100 parts by mass of the functional group-containing fatty acid metal salt, the content of the carboxylic acid hydrazide is within the above range, thereby producing a foam wallpaper. The coloration after foaming can be more efficiently suppressed without excessively lowering the foaming temperature, and the printability can be kept good. If the content of the carboxylic acid hydrazide is 100 parts by mass or less with respect to 100 parts by mass of the functional group-containing fatty acid metal salt, mechanical and material restrictions at the time of producing the foam wallpaper due to excessively low decomposition temperature of the foaming agent. If it can be made small and if it is 30 parts by mass or more, a coloration suppressing effect can be easily obtained.

  The foaming aid of the present embodiment may contain a foaming aid other than the above-described functional group-containing fatty acid metal salt as long as the effects of the present invention are not impaired. Examples of such 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, and fatty acid metal salts such as zinc stearate, calcium laurate, and magnesium octylate. In addition to the system, urea systems such as biurea, metal chlorides such as zinc chloride, metal oxides such as zinc oxide, and the like can be given.

  Moreover, as content of the functional group containing fatty acid metal salt which concerns on this embodiment, it is preferable to exist in the range of 30-100 mass parts with respect to 100 mass parts of total amounts of foaming adjuvant, and 50-70 mass parts. It is more preferable to be within the range. If the content is in the range of 30 to 100 parts by mass with respect to 100 parts by mass of the total amount of foaming aid, a resin composition having better workability and expansion ratio is obtained while sufficiently maintaining printability. be able to.

  The total amount of the foaming aid according to the present embodiment is preferably in the range of 80 to 200 parts by mass, more preferably in the range of 100 to 150 parts by mass with respect to 100 parts by mass of the foaming agent. . If the content is in the range of 80 to 200 parts by mass with respect to 100 parts by mass of the foaming agent, coloration after foaming can be more efficiently suppressed without excessively lowering the foaming temperature during the production of the foam wallpaper. Also, the printability can be kept good. If the total amount of the foaming aid is 200 parts by mass or less with respect to 100 parts by mass of the foaming agent, mechanical and material restrictions during the production of the foamed wallpaper due to the excessively low decomposition temperature of the foaming agent can be reduced. If it is 80 parts by mass or more, sufficient foaming can be obtained without excessively long heating and high temperature in the foaming step, and discoloration due to thermal deterioration of the base material and oxidation deterioration of the resin can be suppressed. Can do.

  The resin component according to the present embodiment preferably contains a non-chlorine thermoplastic resin from the viewpoint of preventing generation of toxic gas such as dioxin during combustion. Non-chlorinated thermoplastic resins include, for example, ethylene homopolymers, copolymers of ethylene and other olefins, polyolefin resins (single olefin polymers such as polypropylene, polybutene, polymethylpentene, etc., two or more olefins Random or block copolymer), styrene resin (polystyrene, acrylonitrile / styrene copolymer (AS), acrylonitrile / butadiene / styrene copolymer (ABS), etc.), ethylene copolymer (ethylene-vinyl acetate copolymer) , Ethylene-methyl methacrylate copolymer, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-methacrylic acid copolymer, etc.). These can be used alone or in combination of two or more.

  Especially, it is preferable that the resin part which concerns on this embodiment contains the ethylene homopolymer or the copolymer of ethylene and another olefin. By using an ethylene homopolymer or a copolymer of ethylene and another olefin, since the surface energy of the base resin is large, the effect of improving the ink affinity due to the reduction of bleed out is exhibited more greatly.

  Ethylene homopolymers and copolymers of ethylene and other olefins are non-polar non-halogen thermoplastic resins, and by using these, it is possible to suppress an increase in viscosity when the amount of filler is increased. 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.

  As low-density polyethylene, for example, commercially available products such as Novatec LD LC802A, Novatec LD LC604 (above, made by Nippon Polyethylene), Ube Polyethylene J2516 (made by Ube Maruzen Polyethylene) 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 0.88 g / cm ³ or more 0.91 g / cm ^3. Density ultra low density polyethylene is preferably not less density 0.88 g / cm ³ or more 0.90 g / cm ^3, more preferably less density 0.89 g / cm ³ or more 0.90 g / cm ^3. 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 140 ° C, more preferably 60 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 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.

  The total resin content is preferably 20 to 80% by mass, more preferably 40 to 75% by mass, and 50 to 70% by mass based on the total amount of the resin composition. More preferably it is. In this case, the resin component may be cross-linked.

  In addition, the resin composition according to the present 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.

  The addition amount of the pigment is preferably 5 to 50% by mass, more preferably 10 to 30% by mass based on the total amount of the resin composition.

  Moreover, well-known additives, such as a flame retardant, a cell regulator, a stabilizer, and a lubricant, can be used for a resin composition as needed.

  Examples of the flame retardant include metal oxide flame retardants such as magnesium hydroxide and aluminum hydroxide, phosphorus flame retardants such as phosphate ester, and bromine flame retardants such as tetrabromobisphenol A.

  Examples of the cell regulator include 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.

  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.

[Resin sheet]
The resin sheet according to the present embodiment is formed from the resin composition according to the present embodiment. The resin sheet according to the present embodiment can be obtained, for example, by extrusion film-forming the resin composition according to the present embodiment.

  Examples of the extrusion film forming method include extrusion molding such as T-die extrusion method, T-die extrusion simultaneous lamination method, T-die extrusion tandem lamination method, circular die extrusion method, and circular die inflation extrusion method.

  The resin sheet according to the present embodiment is produced not only by extrusion molding but also by known molding methods such as injection molding, press molding, blow molding, calendar molding, coating molding, cast molding, dipping molding, vacuum molding, transfer molding, and the like. be able to.

  The resin composition can be used by appropriately pelletizing each component after melting, kneading and dispersing with an extruder. The extruder may be a single-screw extruder or a twin-screw extruder, but a twin-screw extruder is preferable in view of the influence on productivity and quality.

  Extrusion film forming conditions include an extrusion temperature of 100 to 160 ° C. and an extrusion pressure of 2 to 50 MPa. From the viewpoint of setting the melting point of the polyethylene component to be equal to or higher than the melting point of the polyethylene component while suppressing the decomposition of the foaming agent component, the extrusion temperature is preferably 110 to 150 ° C, more preferably 120 to 140 ° C. From the viewpoint of extrusion stability, the extrusion pressure is preferably 3 to 40 MPa, more preferably 3 to 30 MPa.

  Although the thickness of a resin sheet can be suitably set according to a use, if it is a foam wallpaper use, it can be 50-200 micrometers, for example.

  The 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 resin composition contains a silane crosslinkable resin, superheated steam treatment and water crosslinking treatment can be performed.

  In the electron beam irradiation treatment, for example, the resin sheet can be crosslinked by irradiating an electron beam from one side or both sides of the formed resin sheet. Although the electron beam irradiation conditions depend on the thickness of the foamed 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.

  The crosslinking treatment of the resin sheet may be performed on the resin composition formed into a film, or may be performed after forming a laminated sheet to be described later.

[Laminated sheet]
The laminated sheet according to the present embodiment includes a base material and the resin sheet provided on the base material. The laminated sheet can be obtained by laminating a resin sheet on a substrate. The laminating method is not particularly limited, and examples thereof include a method in which a resin sheet and a base material 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 It can suppress that the unevenness | corrugation of is transferred to a resin sheet. Moreover, when a resin sheet contains a silane crosslinkable resin, a silane crosslinkable resin can be bridge | crosslinked efficiently by superheated steam.

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 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 .

  Further, from the viewpoint of improving the adhesion between the base material and the resin sheet, the surface on the side of the base material where the resin sheet is provided is subjected to easy adhesion processing such as corona discharge treatment, plasma treatment, ozone treatment, etc. Alternatively, an easy adhesion treatment layer formed from an acrylic-butyl copolymer, polyurethane composed of isocyanate and polyol, or the like may be provided.

[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 foam wallpaper includes, for example, a step of laminating the above-described resin sheet on a substrate to obtain a laminated sheet, and a step of forming a foamed resin layer by foaming a foaming agent contained in the resin sheet. And can be obtained by a manufacturing method.

  Foaming of the foaming agent can be performed by heating the resin sheet. The heating conditions can be appropriately set depending on the components constituting the resin sheet, and are not particularly limited. However, heating is preferably performed at 160 ° C. to 280 ° C. for 10 seconds to 120 seconds, and 220 ° C. to 240 ° C. at 20 ° C. It is more preferable to heat for 2 seconds to 40 seconds, and further more preferable to heat at 220 ° C. for 40 seconds.

  As another embodiment, the foam wallpaper can be obtained by a method including a step of forming a foamed resin layer by foaming a foaming agent contained in the resin sheet in the laminated sheet.

  Furthermore, in the foamed wallpaper according to the present embodiment, the surface of the foamed resin layer opposite to the base material may have an uneven shape. The method for providing the uneven shape is not particularly limited. For example, by using heat at the time of heating and 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 texture, a satin texture, a grained grain, a hairline, and a straight line groove. Can be selected as appropriate.

  The foamed wallpaper according to the present embodiment may be provided with 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 pattern layer and a surface protective layer can be provided before foaming a 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.

[Production of foam wallpaper]
(Examples 1-4, Comparative Examples 1-4)
Using a T-die having a coat hanger type manifold, using a barrier type screw with a screw diameter (D) of 65 mm and L / D = 32, the composition shown in Table 1 (the numerical values in the table indicate parts by mass) A resin composition having a thickness of 100 μm was formed at an extrusion temperature of 125 ° C. to obtain resin sheets, respectively.

  Each of the resin sheets was irradiated with an electron beam at an acceleration voltage of 200 kV and an irradiation dose of 50 kGy to crosslink the resin component.

Next, on the backing paper (KJ Special Paper, WK-6651HT, weight 65 g / cm ² ), the resin sheets formed in Examples and Comparative Examples were placed and heated at 110 ° C. with a press pressure of 5 MPa. The laminate sheet was obtained by pressing for 2 minutes under the conditions and heat-sealing.

  After the corona discharge treatment was performed on the resin sheet side surface of the obtained laminated sheet, a pattern was printed using a water-based ink (Daiichi Seika Kogyo Co., Ltd., Hydrick WP) with a gravure printing machine. Next, each laminated sheet was heated in an oven at 240 ° C. for 25 seconds to foam the foaming agent, thereby producing a foamed wallpaper.

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

[Low density polyethylene]
Resin A: Novatec LD LC604 (manufactured by Nippon Polyethylene Co., Ltd., trade name, density = 0.918 g / cm ³ )

[Ultra low density polyethylene]
Resin B: TAFMER DF140 (Mitsui Chemicals, trade name, density = 0.905 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 Chemical Industry Co., Ltd., trade name, azodicarbonamide foaming agent)

Foaming aid A: ZS-6 (Nitto Kasei Kogyo Co., Ltd., trade name, zinc 12-hydroxystearate)
Foaming aid B: ADH (manufactured by Nippon Kasei Co., Ltd., trade name, adipic acid dihydrazide)
Foaming aid C: 4-methylbenzoic acid hydrazide (Tokyo Chemical Industry Co., Ltd., compound name)
Foaming aid D: ADK STAB OF-101 (manufactured by ADEKA Corporation, trade name, 1: 1 mixture by weight of fatty acid metal salt such as zinc stearate and calcium carbonate)

Stabilizer: AO-50 (trade name, phenolic antioxidant manufactured by ADEKA Corporation)

Lubricant: ADK STAB AP-546 (trade name, manufactured by ADEKA Corporation)

[Evaluation of foam wallpaper]
The foamed wallpaper thus produced was evaluated for foaming magnification, ink adhesion, and discoloration according to the following methods.

(Foaming ratio)
The thickness (a) of the dried foamed resin layer before foaming was measured and used as the initial value. Next, the thickness (b) of the foamed resin layer of the foamed wallpaper after foaming in the foaming furnace was measured, and (b) / (a) was calculated as the foaming ratio. If the expansion ratio is 6 or more, it can be said that it has good foamability. The results are shown in Table 2.

(Ink adhesion)
The adhesion test of the picture layer by a tape (Nichiban Co., Ltd., CT-24) was performed on the laminated sheet on which the textile pattern was printed. Regarding adhesion, “◎” indicates that the pattern layer remains 99% or more compared to before the test, “◯” indicates that the residual rate of the pattern layer is 50% or more and less than 99%, and “<” indicates less than 50%. The thing was made into "x". The results are shown in Table 2.

(discoloration)
The color tone of the foamed wallpaper after foaming was visually evaluated. Regarding discoloration, “◎” indicates that there is no difference compared to the foamed wallpaper of Comparative Example 1, “○” indicates that yellowing is hardly observed, and “×” indicates that yellowing is not observed. . The results are shown in Table 2.

[Evaluation of laminated sheet]
In the same manner as described above, laminated sheets of Examples 1 to 4 and Comparative Examples 1 to 4 were obtained. About these laminated sheets, according to the following method, the wettability after a corona treatment and the contact angle with respect to ink were evaluated. The results are shown in Table 2.

(Wettability)
Corona discharge treatment was applied to the resin sheet side surface of the laminated sheet. The surface subjected to the corona discharge treatment was tested as described in JIS K6768 using a mixed liquid for wet tension test (manufactured by Wako Pure Chemical Industries, Ltd., mixed liquid for wet tension test No. 30 to No. 42), The wetting tension (mN / m = N / mm) of the resin sheet was measured.

(Contact angle)
The contact angle was measured using a portable contact angle meter PG-3 manufactured by Matsubo Co., Ltd., and the contact angle with respect to hydric ink (manufactured by Dainichi Seika Kogyo Co., Ltd., Hydrick WP).

  It was confirmed that the resin sheets produced in Examples 1 to 4 have good foamability and sufficient printability and are less likely to be discolored during the foaming process.

Claims (11)

A resin composition for forming the foamed resin layer of a foam wallpaper comprising a base material and a foamed resin layer provided on the base material,
Including a filler, a foaming agent, a foaming aid, and a resin component;
The resin composition in which the said foaming adjuvant contains the functional group containing fatty acid metal salt which has a functional group which contains an active proton in the carbon chain of a fatty acid metal salt, and carboxylic acid hydrazide.   The resin composition according to claim 1, wherein the carboxylic acid hydrazide is a carboxylic acid dihydrazide.   The resin composition according to claim 1 or 2, wherein a content of the carboxylic acid hydrazide is 0.1 to 7 parts by mass with respect to 100 parts by mass of the resin component.   The resin composition according to any one of claims 1 to 3, wherein a content of the carboxylic acid hydrazide is 30 to 100 parts by mass with respect to 100 parts by mass of the functional group-containing fatty acid metal salt.   The resin composition according to any one of claims 1 to 4, wherein the functional group is a hydroxyl group. Wherein the resin component comprises at least a density of 0.91 g / cm ³ or more 0.94 g / cm ³ or less of low density polyethylene, a resin composition according to any one of claims 1 to 5. Wherein the resin component further comprises an ultra low density polyethylene density of less than 0.88 g / cm ³ or more 0.91 g / cm ^3, the resin composition according to claim 6.   A resin sheet obtained by extrusion film-forming the resin composition according to claim 1.   The resin sheet according to claim 8, which has been subjected to a crosslinking treatment.   A laminated sheet comprising: a base material; and the resin sheet according to claim 8 or 9 provided on the base material. A foam wallpaper comprising a base material and a foamed resin layer provided on the base material,
The foam wallpaper obtained by foaming the foaming agent contained in the said resin sheet in the lamination sheet of Claim 10.