Composition for self-adhesive foamed sheet, self-adhesive foamed sheet, self-adhesive laminate, and method for producing self-adhesive laminate

Abstract

To provide a self-adsorbable foamed sheet having excellent deodorizing and adsorbing properties, and a composition for self-adsorbable foamed sheets that can provide the self-adsorbable foamed sheet.SOLUTION: A composition for self-adsorbable foamed sheets contains a polymer, and a metal-containing oxycellulose nanofiber containing a metal other than sodium in the form of salt, the content of the metal-containing oxycellulose nanofiber being 0.1 pt.mass or more and 1.00 pt.mass or less relative to 100 pts.mass of the polymer.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a composition for a self-adhesive foamed sheet, a self-adhesive foamed sheet, a self-adhesive laminate, and a method for producing a self-adhesive laminate.

Background Art

[0002] Conventionally, as an adhesive sheet used by being attached to a smooth adherend such as window glass, a sheet-like member made of a foaming material having a large number of fine pores and having self-adhesive properties, that is, a self-adhesive foamed sheet (hereinafter, may be simply referred to as a "foamed sheet") is used. The adhesion mode of the self-adhesive foamed sheet is not adhesive bonding with glue, but adsorption to an adherend using fine pores. Therefore, the self-adhesive foamed sheet is easier to reattach than a conventional adhesive sheet using glue, and is suitably used for applications such as wallpaper, posters, and stickers. When used for these applications, the self-adhesive foamed sheet is usually used in the form of a self-adhesive laminate (hereinafter, may be simply referred to as a "laminated sheet") laminated with a base material. By applying decoration such as printing to the surface on the base material side of this self-adhesive laminate, it can be advantageously used for the above-mentioned applications.

[0003] By the way, in recent years, with respect to resin foams, adding modified cellulose nanofibers has been studied for the purpose of imparting adsorption performance and strength to odor gases and the like. For example, Patent Document 1 describes that by foaming a composition for a foamed resin containing cellulose nanofibers having a sodium salt type or acid type carboxy group introduced on its surface and a resin emulsion, a foam excellent in strength and capable of adsorbing odors such as ammonia can be obtained.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Therefore, in order to impart deodorizing properties to a self - adsorbing foam sheet which is a resin foam, the inventor of the present invention tried adding the modified cellulose nanofibers of the above - mentioned prior art to the composition for a self - adsorbing foam sheet. However, according to the study by the inventor of the present invention, the self - adsorbing foam sheet containing modified cellulose nanofibers having a carboxy group of sodium salt type or acid type introduced on its surface was not sufficiently deodorizing. Further, when the above - mentioned modified cellulose nanofibers were contained in the self - adsorbing foam sheet, the adsorbability (self - adhesion force) of the self - adsorbing foam sheet to the adherend sometimes decreased. Therefore, there was still room for improvement in achieving both deodorizing properties and adsorbability in the self - adsorbing foam sheet.

[0006] Therefore, an object of the present invention is to provide a self - adsorbing foam sheet excellent in deodorizing properties and adsorbability, and a composition for a self - adsorbing foam sheet capable of providing the self - adsorbing foam sheet. Another object of the present invention is to provide a self - adsorbing laminate excellent in deodorizing properties and adsorbability, and a method for producing the self - adsorbing laminate.

Means for Solving the Problems

[0007] The inventor of the present invention conducted intensive studies for the purpose of solving the above - mentioned problems. As a result, the inventor of the present invention found that a self - adsorbing foam sheet produced using a composition for a self - adsorbing foam sheet containing a polymer and metal - containing oxidized cellulose nanofibers containing a metal other than sodium in the form of a salt, and the content of the metal - containing oxidized cellulose nanofibers being controlled within a predetermined range, is excellent in adsorbability and deodorizing properties, and completed the present invention.

[0008] That is, the object of the present invention is to advantageously solve the above problems. The composition for a self - adsorbing foamed sheet of the present invention contains a polymer and a metal - containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt, and the content of the metal - containing oxidized cellulose nanofiber is 0.1 part by mass or more and 1.00 part by mass or less with respect to 100 parts by mass of the polymer. Thus, if the composition for a self - adsorbing foamed sheet contains a metal - containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt and the content ratio is within the above range, it is possible to achieve both high - level deodorizing properties and adsorbing properties of the obtained foamed sheet.

[0009] In the composition for a self - adsorbing foamed sheet of the present invention, it is preferable that the polymer contains a (meth) acrylate monomer unit. A polymer containing a (meth) acrylate monomer unit is excellent in flexibility and can impart good adsorbing properties to the foamed sheet. In the present invention, the polymer "containing a monomer unit" means that "the repeating unit derived from the monomer is contained in the polymer obtained using the monomer". Also, in the present invention, "(meth) acrylate" means acrylate and / or methacrylate.

[0010] In the composition for a self - adsorbing foamed sheet of the present invention, it is preferable that the number - average fiber diameter of the metal - containing oxidized cellulose nanofiber is 100 nm or less. The metal - containing oxidized cellulose nanofiber having a number - average fiber diameter of 100 nm or less is excellent in dispersibility, and even if the blending amount is small, it can impart desired properties such as deodorizing properties to the obtained foamed sheet. In the present invention, the "number - average fiber diameter" of the metal - containing oxidized cellulose nanofiber can be obtained by measuring the fiber diameters of 5 or more metal - containing oxidized cellulose nanofibers using an atomic force microscope and calculating the number average of the measured fiber diameters.

[0011] In the composition for a self - adsorbing foam sheet of the present invention, it is preferable that the metal - containing oxidized cellulose nanofiber is a metal - containing carboxylated cellulose nanofiber. Carboxylated cellulose nanofibers have excellent dispersibility, and even when the blending amount is small, desired properties such as deodorizing properties can be favorably imparted to the resulting foam sheet.

[0012] In the composition for a self - adsorbing foam sheet of the present invention, it is preferable that the metal other than sodium is at least one selected from the group consisting of silver, zinc, and copper. A metal - containing oxidized cellulose nanofiber containing at least one selected from the group consisting of silver, zinc, and copper has excellent deodorizing properties and can favorably impart deodorizing properties to the resulting foam sheet.

[0013] Also, this invention aims to advantageously solve the above - mentioned problems. The self - adsorbing foam sheet of the present invention is characterized by being formed by foaming and shaping any of the above - described compositions for a self - adsorbing foam sheet into a sheet shape. Thus, a self - adsorbing foam sheet formed by foaming and shaping the above - described composition for a self - adsorbing foam sheet is excellent in deodorizing properties and adsorbing properties.

[0014] The self - adsorbing foam sheet of the present invention preferably has a density of 0.3 g / cm 3 or more. If the density is 0.3 g / cm 3 or more, the strength of the self - adsorbing foam sheet can be sufficiently increased. In the present invention, the density of the self - adsorbing foam sheet can be measured by the method described in the examples.

[0015] Also, this invention aims to advantageously solve the above - mentioned problems. The self - adsorbing laminate of the present invention is characterized by comprising a base material and any of the above - described self - adsorbing foam sheets. Thus, a self - adsorbing laminate comprising the above - described self - adsorbing foam sheet is excellent in deodorizing properties and adsorbing properties.

[0016] Furthermore, the present invention aims to advantageously solve the above problems. The method for manufacturing the self - adsorbing laminate of the present invention includes a step of preparing any of the above - described compositions for the self - adsorbing foamed sheet, a step of foaming the composition for the self - adsorbing foamed sheet to obtain a foamed composition, and a step of forming the foamed composition into a sheet shape on a substrate. Thus, by foaming the above - described composition for the self - adsorbing foamed sheet and forming the obtained foamed composition into a sheet shape on a substrate, a self - adsorbing laminate excellent in deodorizing property and adsorbing property can be obtained.

Effects of the Invention

[0017] According to the present invention, a self - adsorbing foamed sheet excellent in deodorizing property and adsorbing property, and a composition for a self - adsorbing foamed sheet capable of providing the self - adsorbing foamed sheet can be provided. Furthermore, according to the present invention, a self - adsorbing laminate excellent in deodorizing property and adsorbing property, and a method for manufacturing the self - adsorbing laminate can be provided.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described in detail.

[0020] (Composition for Self - Adsorbing Foamed Sheet) The composition for a self - adsorbing foamed sheet of the present invention (hereinafter, also simply referred to as "composition for foamed sheet") includes a polymer and metal - containing oxidized cellulose nanofibers containing a metal other than sodium in the form of a salt, and optionally further includes a solvent and other additives. And the composition for a foamed sheet of the present invention is characterized by containing a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt in the range of 0.1 part by mass or more and 1.00 part by mass or less with respect to 100 parts by mass of the polymer. The composition for a foamed sheet of the present invention is excellent in adsorptivity and deodorizing property, and can be suitably used for producing the self-adhesive foamed sheet and the self-adhesive laminate of the present invention. In addition, the odor to be deodorized in the present invention is not particularly limited, and examples thereof include ammonia odor, methyl mercaptan odor, hydrogen sulfide odor, and the like.

[0021] <Polymer> The polymer used in the composition for a self-adhesive foamed sheet of the present invention forms a resin matrix in the foamed sheet obtained by foaming and molding the composition into a sheet shape.

[0022] As the polymer, any polymer capable of forming a foamed sheet can be used. And the polymer is not particularly limited, but for example, it can contain at least one monomer unit selected from the group consisting of (meth)acrylate monomer units, unsaturated carboxylic acid monomer units, vinyl cyanide monomer units, and alkenyl aromatic monomer units. The polymer preferably contains (meth)acrylate monomer units. This is because flexibility is imparted to the obtained foamed sheet, and the foamed sheet can exhibit good adsorptive force (self-adhesive force). In addition, the polymer may contain monomer units other than (meth)acrylate monomer units, unsaturated carboxylic acid monomer units, vinyl cyanide monomer units, and alkenyl aromatic monomer units (hereinafter referred to as "other monomer units").

[0023] <<(Meth)acrylate monomer unit>> (Meth)acrylate monomer units are repeating units derived from (meth)acrylate monomers. The (meth)acrylate monomer is not particularly limited, and examples thereof include (meth)acrylate alkyl ester monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, sec-butyl (meth)acrylate, n-heptyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-dodecyl (meth)acrylate; (meth)acrylate alkoxyalkyl ester monomers such as 2-methoxyethyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, and ethoxymethyl (meth)acrylate; and the like. In addition, the (meth)acrylate monomer may be used alone or in combination of two or more. In the present invention, “(meth)acryl” means acrylic and / or methacrylic.

[0024] Here, as the (meth)acrylate monomer, from the viewpoint of further enhancing the flexibility of the foamed sheet and ensuring better adhesion of the laminated sheet, (meth)acrylate alkyl ester monomers are preferred, and (meth)acrylate alkyl ester monomers in which the alkyl group (bonded to the non-carbonyl oxygen atom) has 1 to 14 carbon atoms (hereinafter sometimes abbreviated as “C1-14 (meth)acrylate alkyl ester monomer”) are more preferred.

[0025] Examples of the C1-14 (meth) acrylic acid alkyl ester monomer include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, sec-butyl acrylate, n-heptyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, n-octyl methacrylate, and n-dodecyl methacrylate. Among these, n-butyl acrylate, ethyl acrylate, and 2-ethylhexyl acrylate are preferred from the viewpoints of adhesion and cost.

[0026] The proportion of the (meth) acrylate monomer unit in the polymer is preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, particularly preferably 85% by mass or more, preferably 99% by mass or less, more preferably 95% by mass or less, and still more preferably 92% by mass or less, with respect to 100% by mass of all the repeating units (all monomer units) contained in the polymer. If the proportion of the (meth) acrylate monomer unit in the polymer is 60% by mass or more, sufficient adhesion of the foamed sheet and the laminated sheet can be ensured. On the other hand, if the proportion of the (meth) acrylate monomer unit in the polymer is 99% by mass or less, the adhesion of the foamed sheet and the laminated sheet does not increase excessively. Therefore, the resin residue on the adherend of the foamed sheet and the laminated sheet can be suppressed.

[0027] <<Unsaturated carboxylic acid monomer unit>> The unsaturated carboxylic acid monomer unit is a repeating unit derived from an unsaturated carboxylic acid monomer. Specific examples of the unsaturated carboxylic acid monomer include, for example, α,β-ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; α,β-ethylenically unsaturated polycarboxylic acids such as itaconic acid, maleic acid, and fumaric acid; α,β-ethylenically unsaturated polycarboxylic acid partial esters such as monomethyl itaconate, monobutyl maleate, and monopropyl fumarate; and the like. In addition, those having a group that can be derived into a carboxylic acid group by hydrolysis, such as maleic anhydride and itaconic anhydride, can also be used in the same manner. Among these, itaconic acid, acrylic acid, and methacrylic acid are preferred, and acrylic acid is more preferred, from the viewpoints of reactivity with a crosslinking agent described later, stability of the polymer latex, and cost. Note that the unsaturated carboxylic acid monomer may be used alone or in combination of two or more.

[0028] And the proportion of the unsaturated carboxylic acid monomer unit in the polymer is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, preferably 10% by mass or less, more preferably 5% by mass or less, and still more preferably 2.5% by mass or less, with respect to 100% by mass of all repeating units (all monomer units) contained in the polymer. When the proportion of the unsaturated carboxylic acid monomer unit in the polymer is 0.1% by mass or more, the crosslinking reaction by the crosslinking agent described later can proceed sufficiently. As a result, while imparting sufficient strength to the obtained foamed sheet, it is possible to suppress the resin residue on the adherend of the foamed sheet and the laminated sheet. On the other hand, when the proportion of the unsaturated carboxylic acid monomer unit in the polymer is 10% by mass or less, it becomes easy to keep the viscosity of the polymerization system during polymerization within an appropriate range, and there is no such problem that the crosslinking of the polymer proceeds excessively and the self-adhesion of the foamed sheet and the laminated sheet is impaired.

[0029] <<Vinyl cyanide monomer unit>> The vinyl cyanide monomer unit is a repeating unit derived from a vinyl cyanide monomer. Specific examples of the vinyl cyanide monomer include α,β-ethylenically unsaturated nitrile monomers. The α,β-ethylenically unsaturated nitrile monomers are not particularly limited as long as they are α,β-ethylenically unsaturated compounds having a nitrile group. For example, acrylonitrile; α-halogenoacrylonitriles such as α-chloroacrylonitrile and α-bromoacrylonitrile; α-alkylacrylonitriles such as methacrylonitrile and α-ethylacrylonitrile; and the like can be mentioned. Among these, acrylonitrile is preferable from the viewpoint of improving the cohesive force of the composition for the foamed sheet and increasing the breaking strength of the foamed sheet. In addition, the vinyl cyanide monomer may be used alone or in combination of two or more.

[0030] The proportion of the vinyl cyanide monomer unit in the polymer is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, preferably 30% by mass or less, more preferably 20% by mass or less, and still more preferably 15% by mass or less, with respect to 100% by mass of all the repeating units (all monomer units) contained in the polymer. If the proportion of the vinyl cyanide monomer unit in the polymer is 1% by mass or more, sufficient strength can be imparted to the obtained foamed sheet while suppressing the resin residue on the adherend of the laminated sheet. On the other hand, if the proportion of the vinyl cyanide monomer unit in the polymer is 30% by mass or less, sufficient flexibility of the obtained foamed sheet can be ensured, and a foamed sheet and a laminated sheet having good self-adhesion can be obtained.

[0031] <<Alkenyl aromatic monomer unit>> The alkenyl aromatic monomer unit is a repeating unit derived from an alkenyl aromatic monomer. Specific examples of the alkenyl aromatic monomer include, for example, styrene, α-methylstyrene, α-chlorostyrene, vinyltoluene, divinylbenzene, and the like. Among these, styrene is preferable from the viewpoints of polymerizability and cost. Note that the alkenyl aromatic monomer may be used alone or in combination of two or more kinds.

[0032] And the proportion of the alkenyl aromatic monomer unit in the polymer is preferably 0.5% by mass or more, more preferably 1% by mass or more, still more preferably 1.5% by mass or more, preferably 20% by mass or less, more preferably 10% by mass or less, and still more preferably 5% by mass or less, with the total repeating units (total monomer units) contained in the polymer being 100% by mass. If the proportion of the alkenyl aromatic monomer unit in the polymer is 0.5% by mass or more, the intrusion of water into the foamed sheet can be prevented based on the hydrophobicity of the alkenyl aromatic monomer unit, and the water resistance of the foamed sheet and the laminated sheet can be enhanced. On the other hand, if the proportion of the alkenyl aromatic monomer unit in the polymer is 20% by mass or less, the flexibility of the obtained foamed sheet can be sufficiently ensured, and a laminated sheet having good self-adhesive force can be obtained.

[0033] <<Other monomer units>> The other monomer units are repeating units derived from other monomers copolymerizable with the monomers described above. Examples of the other monomers include conjugated diene monomers, α,β-ethylenically unsaturated polyvalent carboxylic acid complete ester monomers, vinyl cyanide monomers, carboxylic acid unsaturated alcohol ester monomers, olefinic monomers, crosslinkable monomers, and the like. These monomers may be used alone or in combination of two or more kinds.

[0034] Specific examples of the conjugated diene monomer include, for example, butadiene, isoprene, 1,3-pentadiene, cyclopentadiene, and the like.

[0035] Specific examples of the α,β-ethylenically unsaturated polyvalent carboxylic acid complete ester monomer include dimethyl fumarate, diethyl fumarate, dimethyl maleate, diethyl maleate, dimethyl itaconate, and the like.

[0036] Specific examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethylacrylonitrile, and the like.

[0037] Specific examples of the carboxylic acid unsaturated alcohol ester monomer include vinyl acetate, and the like.

[0038] Specific examples of the olefin monomer include ethylene, propylene, butene, pentene, and the like.

[0039] The crosslinkable monomer is a monomer capable of efficiently crosslinking inside the polymer molecule and / or between polymer molecules. The crosslinkable monomer is not particularly limited as long as it can crosslink the polymer, and examples include polyfunctional monomers having a plurality of polymerizable unsaturated bonds (excluding the above conjugated diene monomers) and monomers having a crosslinkable functional group. When using a crosslinkable monomer, the proportion of the crosslinkable monomer unit in the polymer is preferably 0.1% by mass or more and 10% by mass or less, with the total repeating units (total monomer units) contained in the polymer being 100% by mass. If the proportion of the crosslinkable monomer unit in the polymer is within the above range, it becomes easy to keep the viscosity of the polymerization system during polymerization within an appropriate range, and it also becomes easy to prevent the crosslinking of the polymer from proceeding excessively and impairing the self-adsorbability of the foamed sheet and the laminated sheet.

[0040] [Polyfunctional monomer] Examples of the polyfunctional monomer include bifunctional monomers such as divinylbenzene, ethylene diacrylate, ethylene dimethacrylate, allyl methacrylate; trifunctional monomers such as trimethylolpropane trimethacrylate; and the like. The polyfunctional monomer preferably has an unsaturated bond at the terminal. The polyfunctional monomer may be used alone or in combination of two or more.

[0041] [Monomer having a crosslinkable functional group] Examples of the monomer having a crosslinkable functional group include monomers having functional groups such as organic acid groups other than carboxy groups, hydroxyl groups, amino groups, amide groups, mercapto groups, and epoxy groups.

[0042] The monomer having the organic acid group is not particularly limited, but typical examples thereof include monomers having an organic acid group such as a sulfonic acid group. In addition to these, monomers containing a sulfenic acid group, a sulfinic acid group, a phosphoric acid group, etc. can also be used.

[0043] Specific examples of the monomer having the sulfonic acid group include α,β-unsaturated sulfonic acids such as allyl sulfonic acid, methallyl sulfonic acid, vinyl sulfonic acid, acrylamide-2-methylpropanesulfonic acid, and salts thereof.

[0044] When using the monomer having the organic acid group, the content of the monomer unit derived from the monomer having the organic acid group in the polymer is preferably 0.1% by mass or more and 10% by mass or less, and more preferably 0.5% by mass or more and 5% by mass or less. When the content of the monomer unit derived from the monomer having the organic acid group in the polymer is within the above range, it becomes easy to keep the viscosity of the polymerization system during polymerization within an appropriate range, and it also becomes easy to prevent the crosslinking of the polymer from proceeding excessively and damaging the self-adsorbability of the foamed sheet and the laminated sheet.

[0045] Note that the monomer unit having the organic acid group is preferably introduced into the polymer by polymerization of the monomer having the organic acid group because it is simple, but after the polymer is formed, an organic acid group may be introduced by a known polymer reaction.

[0046] When using monomers having functional groups other than organic acid groups (hydroxyl group, amino group, amide group, epoxy group), the content of monomer units derived from the monomers of the functional groups other than the organic acid groups in the polymer is preferably 10% by mass or less. When the content of monomer units derived from the monomers of the functional groups other than the organic acid groups in the polymer is 10% by mass or less, it becomes easy to keep the viscosity of the polymerization system during polymerization within an appropriate range, and also to prevent the crosslinking of the polymer from proceeding excessively and impairing the self-adsorbability of the foamed sheet and the laminated sheet.

[0047] In addition, from the viewpoint of sufficiently suppressing the generation of formaldehyde when foaming and curing the composition for the foamed sheet, the polymer preferably does not have an N-methylol group. More specifically, the polymer preferably does not contain monomer units having an N-methylol group. Here, examples of the monomer having an N-methylol group include N-methylolacrylamide and N-methylolmethacrylamide.

[0048] [[Properties]] [Glass transition temperature] The glass transition temperature of the polymer is preferably -10°C or lower, more preferably -13°C or lower, still more preferably -17°C or lower, and particularly preferably -20°C or lower. If the glass transition temperature of the polymer is -10°C or lower, it is possible to ensure sufficient adhesion of the foamed sheet and the laminated sheet while ensuring good adhesion of the foamed sheet and the laminated sheet to the adherend. Thereby, it is possible to prevent moisture from entering between the adherend and the foamed sheet or between the adherend and the laminated sheet. Therefore, the water resistance of the foamed sheet and the laminated sheet can be enhanced. In addition, the lower limit value of the glass transition temperature of the polymer is not particularly limited, but from the viewpoint of sufficiently suppressing the resin residue on the adherend of the foamed sheet and the laminated sheet, it is preferably -40°C or higher. The glass transition temperature of the polymer can be obtained, for example, by measuring the glass transition temperature of a film obtained by drying a polymer latex containing the polymer using a differential scanning calorimeter in accordance with JIS K 7121. As the differential scanning calorimeter, for example, DSC7000X (manufactured by Hitachi High-Tech Science Corporation) can be used.

[0049] [Gel fraction] The gel fraction of the polymer is preferably 95% by mass or less, more preferably 93% by mass or less. If the gel fraction is 95% by mass or less, a foamed sheet and a laminated sheet having appropriate self-adhesion and excellent smoothness can be produced. The lower limit of the gel fraction of the polymer is not particularly limited, but can be, for example, 50% by mass or more, and can be 70% by mass or more. The gel fraction of the polymer can be measured, for example, by the following method. First, the polymer is applied onto a polyethylene terephthalate (PET) film with a thickness of 50 μm using a 250-μm applicator and dried at room temperature for 24 hours to obtain a resin film. Using this film as a sample, a predetermined amount (X) (about 500 mg) is precisely weighed, immersed in 100 ml of ethyl acetate at room temperature for 3 days, then the insoluble matter is filtered through a 200-mesh wire mesh, air-dried at room temperature for 15 hours, then dried at 100 °C for 2 hours, cooled at room temperature, and then the weight (Y) of the sample is measured. Then, the gel fraction is calculated by substituting X and Y into the following formula. Gel fraction (%) = (Y) / (X) × 100

[0050] <<Polymer preparation method>> The polymerization method for obtaining the polymer is not particularly limited, and can be any of solution polymerization, emulsion polymerization, suspension polymerization, bulk polymerization, etc., or other methods. There are also no particular restrictions on the types and amounts of polymerization initiators, emulsifiers, dispersants, etc. used in the polymerization. There are no particular restrictions on the addition methods of monomers, polymerization initiators, emulsifiers, dispersants, etc. during the polymerization. There are also no restrictions on the polymerization temperature, pressure, stirring conditions, etc. The polymer can be used in a solid state, but it is preferably used in the form of a latex containing the polymer (polymer latex), such as a latex obtained by emulsion polymerization or a latex obtained by post-emulsifying the polymer. This is because it is easy to mix the polymer with metal-containing cellulose nanofibers containing a metal other than sodium in the form of a salt, an optionally used solvent, and other additives, and it is also convenient for foaming the resulting composition for a foamed sheet. Here, as described above, when the polymer is used in the preparation of the composition for a foamed sheet in the form of a polymer latex, the solid content concentration of the polymer latex is preferably 40% by mass or more, more preferably 45% by mass or more, still more preferably 50% by mass or more, particularly preferably 52% by mass or more, preferably 70% by mass or less, and more preferably 58% by mass or less from the viewpoint of maintaining the density of the resulting foamed sheet.

[0051] <Metal-containing oxidized cellulose nanofibers containing a metal other than sodium in the form of a salt> The metal-containing oxidized cellulose nanofibers containing a metal other than sodium in the form of a salt, which are used in the composition for a self-adhesive foamed sheet of the present invention, are components that impart deodorizing properties to the foamed sheet produced using the composition for a foamed sheet of the present invention. The metal-containing oxidized cellulose nanofibers are not particularly limited as long as they have deodorizing properties. In addition, the above metal-containing oxidized cellulose nanofibers can impart strength to the resulting foamed sheet. Therefore, the density of the foamed sheet can be reduced while maintaining the strength of the foamed sheet. If the density of the foamed sheet is reduced (that is, if more bubbles are formed in the foamed sheet), the contact area between the metal-containing oxidized cellulose nanofibers and the outside air increases, so the deodorizing power of the foamed sheet improves. Therefore, by including the above metal-containing oxidized cellulose nanofibers in the composition for a foamed sheet, the deodorizing properties of the foamed sheet can be improved while maintaining the strength of the foamed sheet.

[0052] Furthermore, the composition for a foamed sheet of the present invention needs to contain a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt in the range of 0.1 part by mass or more and 1.00 part by mass or less with respect to 100 parts by mass of the polymer. Thereby, in the foamed sheet produced using the composition for a foamed sheet, adsorptivity and deodorizing property can be achieved at a high level simultaneously.

[0053] The reason why the composition for a foamed sheet containing a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt in the above range can achieve high levels of both adsorptivity and deodorizing property of the foamed sheet is not necessarily clear, but it is presumed as follows. That is, when the content of the metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt is less than 0.1 part by mass, it is considered that the deodorizing property of the foamed sheet decreases because there is too little of the metal-containing oxidized cellulose nanofiber that exhibits deodorizing performance. On the other hand, when the above content exceeds 1.00 part by mass, it is considered that the adsorptivity of the obtained foamed sheet to the adherend decreases due to an improvement in the elasticity of the composition for a foamed sheet and a decrease in viscosity, and a decrease in the amount of the resin contacting the adherend.

[0054] From the viewpoint of achieving even higher levels of both adsorptivity and deodorizing property in the obtained foamed sheet, the content of the above metal-containing oxidized cellulose nanofiber in the composition for a foamed sheet is preferably 0.3 part by mass or more, more preferably 0.4 part by mass or more, with respect to 100 parts by mass of the polymer, and preferably 0.9 part by mass or less, more preferably 0.8 part by mass or less.

[0055] <<Properties>> The above metal-containing oxidized cellulose nanofiber is preferably a metal-containing carboxylated cellulose nanofiber. This is because the metal-containing carboxylated cellulose nanofiber has excellent dispersibility, and even when the blending amount in the composition for a foamed sheet is small, desired properties such as deodorizing property can be imparted well to the obtained foamed sheet.

[0056] Here, the carboxylated cellulose nanofiber that constitutes the above metal-containing carboxylated cellulose nanofiber is one in which the primary hydroxyl group at the 6-position of the β-glucose unit of the raw material cellulose is oxidized to a carboxyl group via an aldehyde group. From the viewpoint of sufficiently imparting desired properties to the metal-containing carboxylated cellulose nanofiber, in the carboxylated cellulose nanofiber, it is preferable that the above primary hydroxyl group is oxidized to a carboxyl group in an amount of preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 90 mol% or more.

[0057] The amount of carboxyl groups in the above metal-containing carboxylated cellulose nanofiber can be measured according to the method described in JP-A-2016-141777 or JP-A-2019-199622.

[0058] [Metal other than sodium] The metal other than sodium contained in the above metal-containing oxidized cellulose nanofiber can be a metal according to the properties to be imparted to the metal-containing oxidized cellulose nanofiber. The metal other than sodium is, for example, at least one selected from metals in Groups 2 to 14 and Periods 3 to 6 in the periodic table; more preferably at least one selected from the group consisting of magnesium, aluminum, calcium, titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, tin, barium, and lead; still more preferably at least one selected from the group consisting of aluminum, calcium, iron, cobalt, copper, zinc, and silver; particularly preferably at least one selected from the group consisting of silver, zinc, and copper. Note that metal-containing oxidized cellulose nanofibers containing copper and silver (copper-containing oxidized cellulose nanofibers, silver-containing oxidized cellulose nanofibers) are particularly excellent in deodorizing properties against sulfur-based malodorous gases such as hydrogen sulfide and methyl mercaptan.

[0059] The amount of metals other than sodium in the above-mentioned metal-containing oxidized cellulose nanofibers is not limited as long as it can impart desired properties to the resulting foamed sheet. For example, in the above-mentioned metal-containing carboxylated cellulose nanofibers, the metal other than sodium is preferably present in a proportion of 1 / 3 or more of the molar amount of the carboxyl groups of the carboxylated cellulose nanofibers, and more preferably present in a proportion of 1 / 2 or more. The greater the content ratio of metals other than sodium in the metal-containing oxidized cellulose nanofibers, the more the deodorizing property of the resulting foamed sheet can be improved.

[0060] The metal in the above-mentioned metal-containing cellulose nanofibers can be qualitatively and quantitatively analyzed by ICP-AES according to the methods described in, for example, JP-A-2016-141777 or JP-A-2019-199622.

[0061] [Number average fiber diameter] The number average fiber diameter of the above-mentioned metal-containing oxidized cellulose nanofibers is preferably 100 nm or less, more preferably 50 nm or less, still more preferably 30 nm or less, and particularly preferably 10 nm or less. Metal-containing oxidized cellulose nanofibers with a number average fiber diameter of 100 nm or less have excellent dispersibility, and even when the compounding amount in the composition for the foamed sheet is small, desired properties such as deodorizing property can be well imparted to the resulting foamed sheet.

[0062] [Number average fiber length] Also, the above-mentioned metal-containing oxidized cellulose nanofibers preferably have a number average fiber length of 50 nm or more and 2000 nm or less, more preferably 70 nm or more and 1500 nm or less, still more preferably 100 nm or more and 1000 nm or less, and particularly preferably 400 nm or more and 600 nm or less. If the number average fiber length is 50 nm or more, sufficiently high mechanical strength can be imparted to the resulting foamed sheet. Also, if the number average fiber length is 2000 nm or less, the dispersibility of the metal-containing oxidized cellulose nanofibers can be ensured, and the dispersion can be made highly concentrated enough.

[0063] The number average fiber length of the metal-containing oxidized cellulose nanofibers can be adjusted, for example, by changing the number average fiber length of the natural cellulose used as a raw material, the oxidation treatment conditions, the conditions for dispersing (defibrating) the carboxylated cellulose nanofibers after the oxidation treatment, and the conditions for dispersing (defibrating) after the metal substitution step. Specifically, if the time of the dispersion treatment (defibrating treatment) is lengthened, the number average fiber length can be shortened.

[0064] The number average fiber length of the above-mentioned metal-containing oxidized cellulose nanofibers can be measured, for example, by measuring the fiber lengths of 5 or more metal-containing oxidized cellulose nanofibers using an atomic force microscope and calculating the average value of the obtained measurement values. As the atomic force microscope, for example, Dimension FastScan AFM (manufactured by BRUKER, Tapping mode) can be used.

[0065] [Average degree of polymerization] Further, the above-mentioned metal-containing oxidized cellulose nanofibers preferably have an average degree of polymerization (average value of the number of glucose units contained in the cellulose molecule) of 100 or more and 2000 or less, more preferably 300 or more and 1500 or less, still more preferably 500 or more and 1000 or less, and particularly preferably 500 or more and 700 or less. If the average degree of polymerization is 100 or more, sufficiently high mechanical strength can be imparted to the foamed sheet. Further, if the average degree of polymerization is 2000 or less, the dispersibility of the metal-containing oxidized cellulose nanofibers can be ensured, and when made into a dispersion, the dispersion can be made into a sufficiently high concentration.

[0066] The average degree of polymerization of the above-mentioned metal-containing oxidized cellulose nanofibers can be adjusted by changing the average degree of polymerization of the natural cellulose used as a raw material, the oxidation treatment conditions, the conditions for dispersing (defibrating) the carboxylated cellulose nanofibers after the oxidation treatment, the conditions for dispersing (defibrating) after the metal substitution step, and the like.

[0067] The average degree of polymerization of the above metal-containing oxidized cellulose nanofibers can be measured, for example, in accordance with “Viscosity measurements of cellulose / SO 2- amine-dimethylsulfoxide solution”, Sen’i Gakkaishi, 45, 299-306 (1989).

[0068] <<Usage mode>> The above metal-containing oxidized cellulose nanofibers can be used in the form of a dispersion liquid dispersed in a dispersion medium such as water. In this dispersion liquid, the metal-containing oxidized cellulose nanofibers are preferably highly dispersed at a level where the number-average fiber diameter is 100 nm or less, more preferably 2 nm or more and 50 nm or less, still more preferably 2 nm or more and 10 nm or less, and particularly preferably 2 nm or more and 5 nm or less. Therefore, by using the said dispersion liquid, the composition for foamed sheets which can obtain the foamed sheet excellent in a deodorizing effect can be obtained favorably. Specifically, if the dispersion liquid containing metal-containing oxidized cellulose nanofibers is added to the above-mentioned polymer or polymer latex as it is, and the obtained liquid mixture is stirred, the composition for foamed sheets in which the metal-containing oxidized cellulose nanofibers are sufficiently dispersed can be obtained favorably. Further, when the dispersion liquid containing metal-containing oxidized cellulose nanofibers is added little by little to the stirred polymer or polymer latex using a pipette or the like, aggregation of the metal-containing oxidized cellulose nanofibers can be prevented, which is preferable. Here, the solid content concentration of the metal-containing cellulose nanofibers in the dispersion liquid is preferably 0.1% or more and 2.0% or less. If the solid content concentration is 0.1% or more, it is possible to prevent the content of the dispersion medium such as water in the obtained composition for foamed sheets from increasing and the viscosity of the composition from decreasing, and to form a smoother and more uniform sheet. On the other hand, if the solid content concentration is 2.0% or less, it is possible to prevent the dispersion liquid from pseudo-gelatinizing into a jelly state and further improve the dispersibility of the metal-containing cellulose nanofibers in the obtained composition for foamed sheets. When using solid metal-containing oxidized cellulose nanofibers, the above dispersion may be dried by known means.

[0069] <<Manufacturing Method>> The metal-containing oxidized cellulose nanofibers containing a metal other than sodium used in the composition for a foamed sheet of the present invention can be produced, for example, according to the methods described in JP-A-2016-141777 and JP-A-2019-199622. The metal-containing oxidized cellulose nanofibers containing a metal other than sodium produced as described above are usually obtained as a dispersion dispersed in a dispersion medium such as water.

[0070] <Solvent> The solvent that the composition for a foamed sheet of the present invention may optionally contain is not particularly limited, but water is preferred. Here, when water is used as the solvent, the water contained in the composition for a foamed sheet can be, for example, water derived from the polymer latex, and / or water derived from the aqueous dispersion of metal-containing oxidized cellulose nanofibers containing a metal other than sodium in the form of a salt, and / or water derived from other additives.

[0071] <Other Additives> The composition for a foamed sheet of the present invention can optionally contain various additives for improving the processability in the manufacturing processes of the foamed sheet and the laminated sheet and for improving the performance of the obtained foamed sheet and laminated sheet. Examples of such additives include crosslinking agents, foam stabilizers such as higher fatty acid salts and surfactants, foaming aids, thickeners, fillers, antiseptics, fungicides, gelling agents, flame retardants, anti-aging agents, antioxidants, pigments, dyes, tackifiers, conductive compounds, water repellents, oil repellents, and the like. Note that specific examples of the other additives described above are not particularly limited, and known additives, for example, those described in WO 2016 / 147679, can be used.

[0072] <<Crosslinking Agent>> As the crosslinking agent optionally contained in the composition for a foamed sheet of the present invention, there is no particular limitation as long as it can form a crosslinked structure with the above-described polymer (particularly, the unsaturated carboxylic acid monomer unit of the above-described polymer). Examples of such crosslinking agents include carbodiimide-based crosslinking agents; epoxy-based crosslinking agents; oxazoline-based crosslinking agents; polyfunctional isocyanate-based crosslinking agents such as tolylene diisocyanate, trimethylolpropane tolylene diisocyanate, diphenylmethane triisocyanate; metal salt-based crosslinking agents; metal chelate-based crosslinking agents; peroxide-based crosslinking agents; and the like. Among them, epoxy-based crosslinking agents are preferably used, and compounds having two or more epoxy groups in one molecule are more preferably used. And as the epoxy-based crosslinking agent, fatty acid polyglycidyl ether, glycerol polyglycidyl ether, and ethylene glycol diglycidyl ether are preferable.

[0073] Here, the epoxy-based crosslinking agent may be synthesized by a known method or a commercially available product may be used. Examples of commercially available epoxy-based crosslinking agents include "Ricbond (registered trademark)" manufactured by Japan Coating Resin Co., Ltd. The epoxy-based crosslinking agent forms a crosslinked structure intramolecularly or intermolecularly of the polymer by the reaction of the epoxy groups it has with functional groups in the above polymer (for example, carboxylic acid groups derived from unsaturated carboxylic acid monomer units). By using an epoxy-based crosslinking agent, a foamed sheet having appropriate self-adhesion and excellent strength can be formed. Therefore, when using a composition for a foamed sheet containing an epoxy-based crosslinking agent as a crosslinking agent, it is possible to suppress the resin residue on the adherend of the foamed sheet and the laminated sheet.

[0074] In the present invention, it is preferable not to use crosslinking agents that cause the generation of formaldehyde, such as melamine-formaldehyde resins, urea-formaldehyde resins, and phenol-formaldehyde resins.

[0075] Here, the compounding amount of the crosslinking agent in the composition for the foamed sheet is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, still more preferably 3 parts by mass or more, preferably 20 parts by mass or less, and more preferably 10 parts by mass or less per 100 parts by mass of the polymer described above. By the compounding amount of the crosslinking agent being within the above-described range, a foamed sheet with appropriately maintained strength and elasticity can be obtained. Therefore, when the pressure applied to the foamed sheet is released, the foam cells in the crushed foamed sheet can recover to their original shape. And while ensuring the self-adhesion of the foamed sheet and the laminated sheet, the resin residue on the adherend of the foamed sheet and the laminated sheet can be sufficiently suppressed.

[0076] <<Foaming agent>> As the foaming agent, fatty acid ammonium such as ammonium stearate; sulfonic acid type anionic surfactants such as alkyl sulfosuccinate; quaternary alkyl ammonium chloride; alkyl betaine amphoterics; and fatty acid alkanolamine and the like can be used.

[0077] <<Thickener>> As the thickener, acrylic polymers such as sodium polyacrylate; inorganic compound fine particles such as fine silica; and reactive inorganic compounds such as magnesium oxide can be used.

[0078] <Properties of the composition for the foamed sheet> When the composition for a foamed sheet contains a solvent (in the form of a dispersion in which metal-containing oxidized cellulose nanofibers are dispersed), the viscosity of the composition for a foamed sheet is preferably 800 mPa·s or more and 10,000 mPa·s or less, more preferably 900 mPa·s or more and 8,000 mPa·s or less, and even more preferably 1,000 mPa·s or more and 7,500 mPa·s or less. If the viscosity of the composition for a foamed sheet is 1,000 mPa·s or more, it is possible to prevent dripping from occurring when applying the foamed composition formed from the composition for a foamed sheet onto a substrate to form a foamed sheet, which would otherwise make it difficult to control the thickness. On the other hand, if the viscosity of the composition for a foamed sheet is 10,000 mPa·s or less, it is also possible to avoid difficulty in controlling the foaming ratio by mechanical foaming when forming the foamed sheet. Note that the viscosity of the composition for a foamed sheet can be measured by the method described in the examples.

[0079] Also, the pH of the composition for a foamed sheet is preferably 5 or more, more preferably 7 or more, and even more preferably 8 or more. Also, it is preferably 10 or less, more preferably 9.7 or less, and even more preferably 9.5 or less. If the pH of the composition for a foamed sheet is 5 or more, it is possible to favorably prevent precipitation, aggregation of nanofibers, and sedimentation due to aggregation of the removed metal ions caused by the removal of the metal of the metal-containing cellulose nanofibers containing a metal other than sodium in the form of a salt to form a carboxylic acid. On the other hand, if the pH of the composition for a foamed sheet is 10 or less, it is possible to favorably prevent a decrease in the strength of the foamed layer caused by the difficulty of the cross-linking reaction proceeding when a cross-linking agent is used. Note that the pH of the composition for a foamed sheet can be measured by the method described in the examples.

[0080] <Method for producing a composition for a foamed sheet> The composition for a foamed sheet of the present invention can be produced by mixing a polymer and metal-containing oxidized cellulose nanofibers containing a metal other than sodium in the form of a salt with a solvent and other additives used as desired by any method.

[0081] For example, when a polymer latex is used in preparing a composition for a foamed sheet, a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt and other optional additives may be added to the polymer latex and mixed by a known method.

[0082] Also, for example, when a dispersion of a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt is used in preparing a composition for a foamed sheet, a solid polymer or polymer latex and other optional additives may be added to the dispersion and mixed by a known method.

[0083] Furthermore, for example, when no solvent is used in preparing a composition for a foamed sheet, a solid polymer, a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt, and other optional solid additives may be mixed by a known method, such as using a known roll, Henschel mixer, kneader, etc.

[0084] Note that from the viewpoint of favorably dispersing a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt in the composition for a foamed sheet, a dispersion of a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt (for example, an aqueous dispersion) is added to a polymer latex under stirring to obtain a mixed solution, and then, optionally, other additives are added to the mixed solution and further mixed by a known method. Among the other additives, those that increase the viscosity within the system, such as crosslinking agents and thickeners, are preferably added as late as possible so that the composition within the system is kept uniform.

[0085] (Self-adhesive foamed sheet) The self-adhesive foamed sheet of the present invention is formed by foaming and shaping the composition for a foamed sheet of the present invention described above into a sheet shape.

[0086] <Properties> The density of the self - adhering foamed sheet is not particularly limited, but it is preferably 0.3 g / cm 3 or more, more preferably 0.4 g / cm 3 or more, and preferably 0.7 g / cm 3 or less, more preferably 0.6 g / cm 3 or less. If the density of the foamed sheet is 0.3 g / cm 3 or more, the strength of the foamed sheet can be ensured. On the other hand, if the density of the foamed sheet is 0.7 g / cm 3 or less, while ensuring the deodorizing property of the foamed sheet, the air - bleeding property (the ability to easily remove the air pockets remaining between the foamed sheet and the adherend) can be sufficiently enhanced.

[0087] The thickness of the foamed sheet is preferably 30 μm or more, more preferably 50 μm or more, still more preferably 100 μm or more, and preferably 3 mm or less, more preferably 1 mm or less, still more preferably 500 μm or less, and particularly preferably 400 μm or less. If the thickness of the foamed sheet is 30 μm or more, the deodorizing property and mechanical strength of the foamed sheet and the laminated sheet can be sufficiently ensured. On the other hand, if the thickness of the foamed sheet is 3 mm or less, a laminated sheet excellent in repeatability of pasting (rework performance) can be obtained.

[0088] The foamed sheet preferably contains continuous bubbles in which a plurality of bubbles communicate with each other. If the foamed sheet contains such continuous bubbles, the air trapped between the foamed sheet and the adherend can be easily removed to the outside of the foamed sheet through the continuous bubbles, so that the air - bleeding property of the foamed sheet is further improved, and the foamed sheet can be neatly and easily pasted onto the adherend. Also, if the foamed sheet contains such continuous bubbles, the contact area with the outside air increases and more odor components can be deodorized, so that the deodorizing property of the foamed sheet is further improved. When the foamed sheet is used as the foamed layer of the self - adhering laminate described later, from the viewpoint of further improving the air - bleeding property and deodorizing property, the continuous bubbles in the foamed sheet preferably include continuous bubbles extending in the plane direction of the foamed sheet. Closed cells in the foamed sheet can usually be confirmed by observing the cross-section of the foamed sheet with, for example, a laser microscope, a digital microscope, a scanning electron microscope, etc. In addition, the above-mentioned closed cells can also be confirmed at the stage of the foamed composition obtained by foaming the composition for the foamed sheet. The closed cells can be confirmed, for example, by putting the foamed composition into a transparent container and observing it with X-ray CT.

[0089] The properties (density, thickness, closed cells, hardness, etc.) of the foamed sheet can be adjusted by changing, for example, the mixing ratio of the bubbles, the composition of the composition for the foamed sheet, the solid content concentration, the viscosity, and the drying and cross-linking conditions in the manufacturing method of the foamed sheet described later.

[0090] <Method for manufacturing self-adhesive foamed sheet> The above self-adhesive foamed sheet can be manufactured by foaming and forming the above-described composition for the foamed sheet into a sheet shape on an arbitrary base material.

[0091] Specifically, first, an uncured foamed composition is obtained by foaming the above-described composition for the foamed sheet. Here, when the composition for the foamed sheet is in the form of a dispersion, a foamed dispersion is obtained.

[0092] As the foaming method, mechanical foaming is usually adopted. The foaming ratio may be adjusted as appropriate, but is usually 1.2 times or more and 5 times or less, preferably 1.5 times or more and 4 times or less. The method of mechanical foaming is not particularly limited, but can be carried out by mixing a certain amount of air into the dispersion of the composition for the foamed sheet and continuously or batchwise stirring it with an oximixer, a whipper, etc. The foamed dispersion thus obtained becomes creamy. By forming pores through the above-mentioned mechanical foaming, a foamed sheet with excellent air permeability can be finally obtained. When the foaming ratio is 1.2 times or more, it is possible to prevent the decrease in air permeability, and when it is 5 times or less, it is possible to prevent the decrease in the strength of the foamed sheet.

[0093] Next, the above-mentioned foaming composition is formed into a sheet. The method of forming the foaming composition into a sheet is not particularly limited. Suitable methods include, for example, a method of applying the foaming composition in a sheet form on an arbitrary substrate. As the substrate, although not limited, the substrates exemplified in the section of (self-adhesive laminated sheet) described later or a release process paper (hereinafter referred to as "substrate, etc.") having releasability can be used. As a method of applying the foaming composition onto the substrate, etc., generally known coating devices such as a roll coater, a reverse roll coater, a screen coater, a doctor knife coater, and a comma knife coater can be used.

[0094] Next, the foaming composition formed into a sheet on the substrate, etc. is solidified. The solidification of the foaming composition is carried out, for example, by crosslinking the polymer of the foaming composition. The method of crosslinking the polymer is not limited, but a method of heat-drying the foaming composition is preferable. The method of heat-drying is not particularly limited as long as it can dry the foaming composition on the substrate, etc. and crosslink the polymer, and known drying furnaces (for example, a hot air circulation type oven, a hot oil circulation hot air chamber, a far-infrared heater chamber) can be used. The drying temperature can be, for example, 60°C or higher and 180°C or lower. Also, it is preferable to perform multi-stage drying in which drying is not carried out at a constant temperature, but drying is carried out from the inside at a low temperature in the initial stage of drying, and then sufficiently dried at a higher temperature in the later stage of drying.

[0095] In this way, a self-adhesive foamed sheet in which the sheet-like foaming composition is solidified on the substrate, etc. is formed. At this time, if a release process paper is used, the self-adhesive foamed sheet can be easily separated from the process paper, and the self-adhesive foamed sheet can be obtained as an independent film.

[0096] The self - adsorbing foam sheet thus obtained is not particularly limited. For example, after a separator film is attached to its surface, it can be wound up by a winder and processed into a convenient size by press cutting, slitting, etc.

[0097] (Self - adsorbing laminate) The self - adsorbing laminate of the present invention comprises a foam layer composed of a foam sheet (the self - adsorbing foam sheet of the present invention) obtained by using the above - described composition for a foam sheet of the present invention, and a base material as a support layer for supporting the foam layer. The foam sheet may be formed directly on the base material or may be formed on the base material via an arbitrary layer. Further, the self - adsorbing laminate of the present invention may have foam sheets on both sides of the base material.

[0098] As the base material in the laminate sheet of the present invention, a paper base material, synthetic paper, plastic base material, fiber base material, metal base material, glass base material, etc. can be used. The thickness of the base material is not particularly limited, but can be, for example, 10 μm or more and 500 μm or less.

[0099] Examples of the paper base material include high - quality paper, art paper, coated paper, kraft paper, and those obtained by laminating a thermoplastic resin such as polyethylene on these paper base materials.

[0100] The synthetic paper is not particularly limited, but is a material in which the surface layer is made paper - like by a combination of a thermoplastic resin and an inorganic filler.

[0101] Examples of the plastic base material include sheet - like base materials made of polyester - based resins such as polyethylene terephthalate and polyethylene naphthalate; polystyrene - based resins; polyvinyl chloride - based resins; acrylic - based resins; polycarbonate - based resins; polyamide - based resins; fluorine - based resins such as polytetrafluoroethylene; polyolefin - based resins such as polyethylene and polypropylene; cyclic polyolefin - based resins, and mixtures or laminates of these resins.

[0102] Examples of the fiber base material include sheet-like base materials made of natural fibers such as cotton and silk; polyamide synthetic fibers; polyester synthetic fibers; polypropylene synthetic fibers; polyvinyl chloride synthetic fibers; polyvinyl alcohol synthetic fibers; semi-synthetic fibers such as acetate; regenerated man-made fibers such as rayon; and mixtures or laminates of these fibers.

[0103] The metal base material is not particularly limited, and examples include sheet-like base materials made of metals such as iron, copper, aluminum, gold, platinum, and silver, and alloys or laminates thereof.

[0104] The glass base material is not particularly limited, and examples include sheet-like base materials made of soda-lime glass, borosilicate glass, alkali-free glass, quartz glass, etc.

[0105] (Method for manufacturing the self-adhesive laminate) The self-adhesive laminate of the present invention can be manufactured, for example, as described above, by foaming and forming the above-described composition for the foamed sheet on a base material to form a self-adhesive foamed sheet in which the sheet-like foamed composition is solidified on the base material. Alternatively, the self-adhesive laminate of the present invention may be manufactured by obtaining the self-adhesive foamed sheet as an independent film as described above and then laminating it on the base material by known means such as an arbitrary adhesive. When manufacturing a self-adhesive laminate provided with foamed sheets on both sides of the base material, after forming a foamed sheet on one surface of the base material as described above, a foamed sheet may be formed on the other (opposite) surface in the same manner, or the foamed sheets as independent films may be laminated on both sides of the base material by known means such as an adhesive.

[0106] Hereinafter, an example of a method for manufacturing a self-adhesive laminate by forming a self-adhesive foamed sheet on a base material will be described with reference to the drawings.

[0107] FIG. 1 shows a flowchart for explaining an example of a method S10 for manufacturing a laminated sheet (hereinafter, may be abbreviated as "manufacturing method S10"). As shown in FIG. 1, the manufacturing method S10 includes a composition preparation step S1, a foaming step S2, and a sheeting step S3 in this order. Hereinafter, each step will be described.

[0108] <Composition preparation step S1> The composition preparation step S1 is a step of preparing the composition for the self-adhesive foamed sheet of the present invention. In the composition preparation step S1, the composition for the self-adhesive foamed sheet of the present invention is manufactured by the method described in the section <Manufacturing method of the composition for the self-adhesive foamed sheet>.

[0109] <Foaming step S2> The foaming step S2 is a step of foaming the composition for the foamed sheet obtained in the composition preparation step S1 to obtain a foamed composition. In the foaming step S2, the composition for the foamed sheet is foamed by the method described in the section <Manufacturing method of the self-adhesive foamed sheet> to manufacture a foamed composition.

[0110] <Sheeting step S3> The sheeting step S3 is a step of forming the foamed composition obtained in the foaming step S2 into a sheet shape on a substrate. In the sheeting step S3, the foamed composition obtained in the foaming step S2 is applied and solidified on the substrate by the method described in the section <Manufacturing method of the self-adhesive foamed sheet> to manufacture a self-adhesive foamed sheet in which a sheet-shaped foamed composition is solidified on the substrate. Thereby, a self-adhesive laminate including a foamed layer made of a self-adhesive foamed sheet and a substrate as a support layer for supporting the foamed layer is obtained.

[0111] And, the laminated sheet obtained through the above-described steps S1 to S3 is not particularly limited. For example, after a separator film is attached to the surface having self-adhesiveness (that is, the surface on the foamed sheet side), it is wound by a winder and can be processed into a convenient size by press cutting, slitting, etc.

[0112] <Use of the laminated sheet> The laminated sheet of the present invention can be printed on its base material surface by, for example, offset printing, seal printing, flexographic printing, silk screen printing, gravure printing, laser printers, thermal transfer printers, inkjet printers, etc. The laminated sheet printed on the base material surface can be used advantageously for outdoor applications such as sales promotion cards, so-called POP cards (posters, stickers, displays, etc.), horticultural POPs (clip labels, etc.), road signs (for funerals, housing display sites, etc.), display boards (such as no entry, forest road work, etc.), and indoor applications such as wallpapers, floor materials, and wall materials.

Examples

[0113] Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples. Also, in a polymer produced by polymerizing a plurality of types of monomers, the proportion of a monomer unit formed by polymerizing a certain monomer in the polymer usually coincides with the ratio (charge ratio) of the certain monomer in all the monomers used for the polymerization of the polymer, unless otherwise specified. And for various measurements and evaluations in the examples and comparative examples, they were carried out according to the following methods.

[0114] (Viscosity of the composition for the foamed sheet) The viscosity of the composition for the foamed sheet was measured at 23°C using a B-type viscometer (manufactured by Lion Corporation, "VISCOTESTER VT-06").

[0115] (pH of the composition for the foamed sheet) The pH of the composition for the foamed sheet was measured at 23°C using a pH meter (pH METER F-52 manufactured by HORIBA).

[0116] (Thickness and density of the foamed layer) Eight laminated sheets were cut into 50 mm × 50 mm squares, and the weight of each (scale: BM-252 manufactured by A&D Company) and the thickness were measured (thickness gauge: PEACOK MODEL H manufactured by Ozaki Manufacturing Co., Ltd.), and the average values were derived. Similarly, eight substrates (synthetic paper, film, etc.) were also cut into 50 mm × 50 mm squares alone, and the weight and thickness of each were measured, and the average values were derived. The weight of the foam layer was calculated by subtracting the average weight of the substrate from the average weight of the laminated sheet. Also, the thickness of the foam layer was calculated by subtracting the average thickness of the substrate from the average thickness of the laminated sheet. The density of the foam layer was calculated by dividing the value by the volume (50 mm × 50 mm × average thickness).

[0117] (Strength of the foam layer) The obtained laminated sheet was cut into a size of 50 mm × 125 mm (width × length) and bonded to a gum tape cut into a size of 50 mm × 150 mm (width × length) from one end of the adhesive layers (the gum tape had 25 mm remaining on the side opposite to the bonded end in the length direction). The excess side of the gum tape in the bonded part of the laminated sheet and the gum tape was peeled off by 25 mm from the end, and the remaining gum tape and 50 mm of the peeled gum tape were folded with 25 mm as the center and the adhesive layers of the gum tape were bonded together. Then, a force was applied to the entire adhesive surface with a roller to bring the adhesive layer of the laminated sheet into close contact with the adhesive surface of the gum tape. The test piece was cut out in parallel with the length direction from the position of 25 mm in width, and two sets of test pieces cut into a size of 25 mm × 125 mm (width × length) were obtained. After leaving these test pieces in a thermo-hygrostat at 60 °C and 80% RH for 1 hour, they were taken out and conditioned for 1 hour in a thermo-hygrostat at 23 °C and 50% RH. The end opposite to the end where the laminated sheet and the gum tape of this test piece were bonded together by the adhesive layers, that is, the end where the adhesive layers of the gum tapes were bonded together and not bonded to the gum tape (the 25 mm × 25 mm part where the gum tape was peeled off first) and the end where the adhesive layers of the gum tape were bonded together were respectively clamped by the upper and lower chucks (distance between chucks: 15 mm) of a tensile testing machine (Autograph AGS-20IS manufactured by Shimadzu Corporation) in the above thermo-hygrostat. Then, when a T-peel test was carried out at a speed of a load cell of 50 N and a test speed of 300 mm / min, the test force was measured, and the test force per unit width was taken as the strength (N / cm) of the foam layer. If this measurement result is 1 N / cm or more, it can be said that it has an appropriate foam layer strength.

[0118] (Self-adhesion (adsorptivity)) After preparing the self - adhering laminated sheet, a test piece cut into a size of 125 mm × 25 mm was prepared. The adsorption surface of the test piece was bonded to a smooth glass surface, pressed with a 2 - kgf load roller from above the test piece, and left for 1 hour in an environment of 23°C and 50% RH. Then, the end of the test piece was fixed to the upper chuck of an autograph (AG - IS manufactured by Shimadzu Corporation), the glass plate was fixed to the lower chuck, and a 180 - degree peel test was carried out at a speed of 300 mm / min in an environment of 23°C and 50% RH. The test force at this time was taken as the self - adhesion force (N / cm).

[0119] (Air permeability) <Evaluation device> The evaluation of air permeability was carried out using the evaluation device 100 shown in Fig. 2. The evaluation device 100 shown in Fig. 2 is a device for evaluating the air permeability of the laminated sheet 50 formed by laminating the foamed sheet 51 and the base material 52, and includes a sample fixing plate 10 having a through - hole 11 and a gas pumping mechanism 40 for pumping air as a gas through the through - hole 11 from the other surface side (upper side in Fig. 2) to one surface side (lower side in Fig. 2) of the sample fixing plate 10 at a constant pressure. Here, the gas pumping mechanism 40 has a syringe 20 whose tip is connected to the through - hole 11 of the sample fixing plate 10 on the other surface side of the sample fixing plate 10, and a weight 30. The syringe 20 is connected to the sample fixing plate 10 with its tip facing vertically downward (lower side in Fig. 2), and includes a needle 21 inserted and fixed into the through - hole 11 of the sample fixing plate 10, a cylindrical outer cylinder 22 whose tip (lower - side end in Fig. 2) is connected to the through - hole 11 via the needle 21, and a piston 23 inserted into the outer cylinder 22 from the rear - end side of the outer cylinder 22. Note that the weight 30 is attached to a flange provided at the rear end (upper - side end in Fig. 2) of the piston 23. Also, in the gas pumping mechanism 40 having the above - described configuration, due to the self - weight of the piston 23 and the weight 30, the piston 23 is pushed into the outer cylinder 22, and the air in the outer cylinder 22 is pumped to one surface side (foamed sheet 51) of the sample fixing plate 10 at a constant pressure through the needle 21 and the through - hole 11. In the evaluation apparatus 100 having the above-described configuration, for example, after the laminated sheet 50 is attached to the surface of one side of the sample fixing plate 10 (the side opposite to the needle 21 side) where the needle 21 is fixed so as to cover the through hole 11 (step (A)), the outer cylinder 22 with the piston 23 to which the weight 30 is attached is connected to the needle 21 until the distance from the tip reaches L, and by measuring the time required for the piston 23 to travel the distance L by the self-weight of the piston 23 and the weight 30 (step (B)), the air permeability of the laminated sheet 50 can be evaluated. That is, the air in the outer cylinder 22 is pushed out from the through hole 11 at a constant pressure by the self-weight of the piston 23 and the weight 30. If the distance L is made constant and the amount of air pushed out from the inside of the outer cylinder 22 is made constant, the lower the air permeability of the laminated sheet 50, the longer the time required for the piston 23 to travel the distance L, and the higher the air permeability of the laminated sheet 50, the shorter the time required for the piston 23 to travel the distance L. Therefore, the air permeability of the laminated sheet 50 can be quantitatively evaluated by the time required for the piston 23 to travel the distance L. In addition, since the evaluation can be performed under the condition that the amount and pressure of the air to be pumped are constant, the air permeability can be evaluated with high repeatability accuracy. Furthermore, since the evaluation can be performed with the laminated sheet 50 attached to the sample fixing plate 10, the air permeability of the laminated sheet 50 in the state of being attached to the adherend can be accurately evaluated. Note that, as the sample fixing plate 10, a transparent polycarbonate plate (50 mm × 50 mm) with a thickness of 1 mm was used, as the syringe 20, a glass syringe with a capacity of 2 mL having a metal syringe needle with a diameter of 2 mm was used, and as the weight 30, a weight of 30 g attached to the piston 23 with double-sided tape was used.

[0120] <Evaluation of air permeability> After the laminated sheet was produced, it was cut into a size of 40 mm × 40 mm and used as a sample to be evaluated. Then, the surface of the prepared sample on the foamed sheet side was attached to the surface of one side (the side opposite to the needle 21 side) of the sample fixing plate 10 to which the needle 21 was fixed so as to cover the through hole 11 and prevent air from entering (step (A)). After that, the outer cylinder 22 with the piston 23 to which the weight 30 was attached was connected to the needle 21 with the piston 23 inserted to the position where the scale reached 2 mL. Then, the hands were released from the weight 30 and the piston 23, and the time required until the piston 23 and the weight 30 stopped dropping by their own weights (i.e., until 2 mL of air was pumped) was measured (step (B)). This measurement operation was repeated three times, and the average value of the measured times was calculated. The smaller this average value is, the better the air permeability of the laminated sheet is indicated.

[0121] (Evaluation of deodorizing property) After the laminated sheet was produced, it was cut out into a size of 100 mm × 100 mm × thickness, and the foamed layer side was attached to a soda glass of 120 mm × 120 mm × 1 mm to obtain a sample. The sample was put into a sampling pack (SMART BAG PA AA-5 manufactured by GL Sciences), and the mouth was heat-sealed and sealed. The sampling pack was degassed using a vacuum pump, and 3 L of a gas with a predetermined concentration (hydrogen sulfide gas: 80 mass ppm, or ammonia gas: 70 mass ppm) was sealed into the sampling pack. Then, the gas concentration (mass ppm) in the pack was measured using a gas detector tube (gas detector tube manufactured by Gastech) at a predetermined time. The faster the gas concentration decreases, the better the deodorizing property is indicated.

[0122] (Production Example 1) (Preparation of polymer latex) To 27.0 parts of deionized water, a monomer mixture consisting of 64 parts of ethyl acrylate, 12 parts of 2-ethylhexyl acrylate, 12 parts of n-butyl acrylate, 9 parts of acrylonitrile, 2 parts of styrene, and 1 part of acrylic acid, and 0.4 part of sodium polyoxyethylene alkyl sulfate (manufactured by Kao Corporation: Latemul E-118B) were mixed and stirred to obtain a monomer emulsion. Next, separately from the above, a glass reaction vessel equipped with a reflux condenser, a dropping funnel, a thermometer, a nitrogen inlet, and a stirrer was prepared. 43.0 parts of deionized water and 0.2 part of sodium polyoxyethylene alkyl sulfate were placed in this glass reaction vessel, and while stirring, the temperature was raised to 80°C. Then, while maintaining the temperature at 80°C, 0.3 part of ammonium persulfate dissolved in 5.7 parts of deionized water was added, and subsequently, the monomer emulsion obtained above was gradually added over 4 hours. After the addition was completed, stirring was continued for another 4 hours, followed by cooling to terminate the reaction, and a reaction mixture was obtained. The polymerization conversion rate at this time was almost 100% (98% or more). The obtained reaction mixture was adjusted to pH 5.0 with 5% aqueous ammonia, 2.5 parts of polyoxyethylene lauryl ether (manufactured by Kao Corporation: Emulgen 120) was added, and then concentration was performed to obtain a polymer latex with a solid content concentration of 58%.

[0123] <Preparation of TEMPO Oxidized Cellulose Nanofiber Aqueous Dispersion> 1 g equivalent of softwood bleached kraft pulp by dry weight, 5 mmol of sodium hypochlorite, 0.1 g (1 mmol) of sodium bromide, and 0.016 g (1 mmol) of TEMPO were dispersed in 100 mL of water, gently stirred at room temperature for 4 hours, and washed with distilled water to obtain TEMPO-catalyzed oxidized pulp (oxidized cellulose). The amount of carboxyl groups in the obtained TEMPO-catalyzed oxidized pulp was 1.4 mmol / g. Thereafter, distilled water was added to the undried TEMPO-catalyzed oxidized pulp to prepare an aqueous dispersion with a solids concentration of 0.1%. Then, using a homogenizer (manufactured by Microtech Nition, Hisotron), the aqueous dispersion was homogenized at 7.5×1000 rpm for 2 minutes, and using an ultrasonic homogenizer (manufactured by Nissei, Ultrasonic Generator), while cooling the periphery of the container with ice, fibrillation treatment was performed at V-LEVEL4 and TIP26D for 4 minutes to obtain an aqueous dispersion containing TEMPO-carboxylated cellulose nanofibers as TEMPO-oxidized cellulose nanofibers. Thereafter, from the TEMPO-carboxylated cellulose nanofiber aqueous dispersion, centrifugation (12000G (120×100 rpm / g), 10 minutes, 12°C) using a centrifuge (manufactured by Sakuma, M201-1VD, angle rotor 50F-8AL) was performed to remove unfibrillated components, and a transparent liquid, an aqueous dispersion of TEMPO-carboxylated cellulose nanofibers with a concentration of 0.1%, was obtained. Note that the TEMPO-carboxylated cellulose nanofibers contained sodium (the first metal) derived from the co-oxidizing agent in the form of a salt. <Preparation of Hydrogen-Substituted TEMPO-Oxidized Cellulose Nanofiber Aqueous Dispersion> To 100 mL of the TEMPO-carboxylated cellulose nanofiber aqueous dispersion, 1 mL of 1 M hydrochloric acid was added under stirring to adjust the pH to 1. Then, stirring was continued for 60 minutes (hydrogen substitution step). Thereafter, the TEMPO-carboxylated cellulose nanofibers gelled by the addition of hydrochloric acid were recovered by centrifugation (12000G), and the recovered TEMPO-carboxylated cellulose nanofibers were sequentially washed with 1 M hydrochloric acid and a large amount of distilled water (first washing step). Next, 100 mL of distilled water was added to obtain a hydrogen-substituted TEMPO-carboxylated cellulose nanofiber aqueous dispersion with a concentration of 0.1% in which the hydrogen-substituted TEMPO-carboxylated cellulose nanofibers were dispersed (first dispersion step). The carboxyl groups on the surface of the hydrogen-substituted TEMPO-carboxylated cellulose nanofibers were measured by FT-IR (manufactured by JASCO Corporation, FT / IR-6100) according to Biomacromolecules (2011, Vol. 12, pp. 518-522), and more than 90% were substituted with the carboxylic acid type.

[0124] <Preparation of Copper-Containing TEMPO-Oxidized Cellulose Nanofiber Aqueous Dispersion> 50 g of the above hydrogen-substituted TEMPO-carboxylated cellulose nanofiber aqueous dispersion with a concentration of 0.1% was stirred, and 18 g of an aqueous copper(II) acetate solution with a concentration of 0.1% was added thereto, and stirring was continued at room temperature for 3 hours (metal substitution step). Thereafter, the carboxylated cellulose nanofibers gelled by the addition of the aqueous copper(II) acetate solution were collected by centrifugation (12,000 G (120 × 100 rpm / g), 10 minutes, 12°C) using a centrifuge (manufactured by SAKUMA, M201-1VD, angle rotor 50F-8AL). Then, the recovered cellulose nanofibers were washed with an aqueous copper(II) acetate solution with a concentration of 0.1%, and next, the recovered cellulose nanofibers were washed with a large amount of distilled water (washing step). Thereafter, 50 mL of distilled water was added, and using an ultrasonic homogenizer (manufactured by Nissei, Ultrasonic Generator), while cooling the surroundings of the container with ice, ultrasonic treatment (for 2 minutes) was performed at V-LEVEL4 and TIP26D to disperse TEMPO carboxylated cellulose nanofibers substituted with copper. Thereafter, from the aqueous dispersion of TEMPO carboxylated cellulose nanofibers substituted with copper, centrifugation (12000G (120×100 rpm / g), for 10 minutes, at 12°C) was carried out using a centrifuge (manufactured by SAKUMA, M201-1VD, angle rotor 50F-8AL) to remove the undispersed components. Thus, an aqueous dispersion of copper-containing TEMPO oxidized cellulose nanofibers (hereinafter, also simply referred to as "TOCN-Cu") with a solid content concentration of 0.1% was obtained. Thereafter, this aqueous dispersion was concentrated using an evaporator to obtain an aqueous dispersion of TOCN-Cu with a solid content concentration of 0.5%.

[0125] <Preparation of Foaming Composition> 200 g of the above polymer latex (solid content concentration 58%) was weighed into a 500 ml disposable cup and stirred (1750 rpm) with a mixer (ROBOMICS manufactured by Tokushu Kika Kogyo Co., Ltd.). To the stirred polymer latex, 234 g of the above TOCN-Cu aqueous dispersion (solid content concentration: 0.5%) (TOCN-Cu content relative to 100 parts by mass of the polymer: 1 part by mass) was gradually added little by little, and stirring was continued for 30 minutes as it was after addition. Thereafter, while stirring the obtained mixture, 8 g of ammonium stearate (Nopco DC-100A manufactured by San Nopco Co., Ltd., concentration 30%) as a foam stabilizer, 6 g of fatty acid polyglycidyl ether (Ricabond EX-8 manufactured by Japan Coating Resin Co., Ltd., concentration 100%) as an epoxy-based crosslinking agent, and 51 g of sodium polyacrylate (Aron A-20L manufactured by Toagosei Co., Ltd., concentration 15%) as a thickening agent were sequentially added to the mixture, and then stirred for 30 minutes to obtain a composition for foamed sheet. The effective component concentration of the composition for foamed sheet was 27%, the viscosity was 1600 mPa·s, and the pH was 8.9. The composition for foamed sheet was foamed 1.5 times using a foaming device (Hand Mixer THM272 manufactured by Tescom) to obtain a foaming composition (foaming liquid) with a density of 0.67 g / cm 3 of.

[0126] (Production Example 2) In Production Example 1, except that 117 g of the above TOCN-Cu aqueous dispersion (solid content concentration: 0.5%) (TOCN-Cu content relative to 100 parts by mass of the polymer: 0.5 part by mass) and 6 g of sodium polyacrylate as a thickener were used, the treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the composition for a foamed sheet was 38%, the viscosity was 1100 mPa·s, and the pH was 9.0. The composition for a foamed sheet was foamed 1.9 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.50 g / cm 3 of.

[0127] (Production Example 3) In Production Example 1, except that 400 g of the above polymer latex (solid content concentration: 58%), 135 g of the above TOCN-Cu aqueous dispersion (solid content concentration: 0.5%) (TOCN-Cu content relative to 100 parts by mass of the polymer: 0.3 part by mass), 16 g of ammonium stearate as a foam stabilizer, 12 g of fatty acid polyglycidyl ether as an epoxy-based crosslinking agent, and 12 g of sodium polyacrylate as a thickener were used, the treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the composition for a foamed sheet was 44%, the viscosity was 1100 mPa·s, and the pH was 8.9. The composition for a foamed sheet was foamed 1.6 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.65 g / cm 3 of.

[0128] (Production Example 4) A foamed liquid with a density of 0.35 g / cm was obtained by foaming the composition for a foamed sheet of Production Example 3 2.9 times using a foaming machine. Otherwise, a foamed composition was obtained in the same manner as in Production Example 3. 3

[0129] (Production Example 5) In Production Example 1, a TOCN-Cu aqueous dispersion with a solid content concentration of 0.9% was prepared. In addition, 300 g of the above polymer latex (solid content concentration: 58%), 19 g of the above TOCN-Cu aqueous dispersion (TOCN-Cu content relative to 100 parts by mass of the polymer: 0.1 part by mass), 12 g of ammonium stearate as a foam stabilizer, 9 g of fatty acid polyglycidyl ether as an epoxy crosslinking agent, and 9 g of sodium polyacrylate as a thickener were used. The treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the composition for a foamed sheet was 54%, the viscosity was 4300 mPa·s, and the pH was 8.7. The composition for a foamed sheet was foamed 2.0 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.49 g / cm 3 of the foamed composition (foaming liquid).

[0130] (Production Example 6) In Production Example 1, 200 g of the above polymer latex (solid content concentration: 58%), 23 g of the above TOCN-Cu aqueous dispersion (solid content concentration: 0.5%) (TOCN-Cu content relative to 100 parts by mass of the polymer: 0.1 part by mass), 8 g of ammonium stearate as a foam stabilizer, 6 g of fatty acid polyglycidyl ether as an epoxy crosslinking agent, and 6 g of sodium polyacrylate as a thickener were used. The treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the foamed composition was 52%, the viscosity was 2500 mPa·s, and the pH was 8.6. The composition for a foamed sheet was foamed 2.8 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.34 g / cm 3 of the foamed composition (foaming liquid).

[0131] (Production Example 7) In Production Example 1, a TOCN-Cu aqueous dispersion with a solid content concentration of 0.9% was prepared. Except that 161 g of the TOCN-Cu aqueous dispersion (TOCN-Cu content relative to 100 parts by mass of the polymer: 1.3 parts by mass), 8 g of ammonium stearate as a foam stabilizer, 6 g of fatty acid polyglycidyl ether as an epoxy-based crosslinking agent, and 6 g of sodium polyacrylate as a thickening agent were used, the treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the foaming composition was 33%, the viscosity was 1100 mPa·s, and the pH was 9.2. The composition for a foamed sheet was foamed 1.8 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.55 g / cm 3 of the foamed composition (foaming liquid).

[0132] (Production Example 8) In Production Example 3, except that the above TOCN-Cu aqueous dispersion was not added (TOCN-Cu content relative to 100 parts by mass of the polymer: 0 parts by mass), the treatment was carried out in the same manner as in Production Example 3 to obtain a composition for a foamed sheet. The effective component concentration of the foaming composition was 57%, the viscosity was 5200 mPa·s, and the pH was 8.4. The composition for a foamed sheet was not foamed, but instead was defoamed using a defoaming machine to obtain a non-foamed liquid with a density of 1.01 g / cm 3 of the non-foamed liquid.

[0133] (Production Example 9) In Production Example 1, the above TOCN-Cu aqueous dispersion was not added (TOCN-Cu content relative to 100 parts by mass of the polymer: 0 parts by mass), and except that 300 g of the above polymer latex (solid content concentration 58%), 12 g of ammonium stearate as a foam stabilizer, 9 g of fatty acid polyglycidyl ether as an epoxy-based crosslinking agent, and 9 g of sodium polyacrylate as a thickening agent were used, the treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the foaming composition was 57%, the viscosity was 7100 mPa·s, and the pH was 8.5. The composition for a foamed sheet was foamed 1.2 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.84 g / cm 3 of the foamed composition (foaming liquid).

[0134] (Production Example 10) The composition for a foamed sheet of Production Example 8 was foamed 1.6 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.62 g / cm 3 3.

[0135] (Production Example 11) In Production Example 2, a composition for a foamed sheet was obtained in the same manner as in Production Example 2, except that the above TOCN-Cu aqueous dispersion was not added (TOCN-Cu content based on 100 parts by mass of the polymer: 0 part by mass). The effective component concentration of the composition for a foamed sheet was 57%, the viscosity was 6500 mPa·s, and the pH was 8.8. The composition for a foamed sheet was foamed 2.5 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.40 g / cm 3 3.

[0136] (Production Example 12) In Production Example 1, an aqueous TOCN-Cu dispersion with a solid content concentration of 0.9% was prepared. And, except that 200 g of the above polymer latex (solid content concentration 58%), 6.2 g of the above TOCN-Cu aqueous dispersion (TOCN-Cu content based on 100 parts by mass of the polymer: 0.05 part by mass), 8 g of ammonium stearate as a foam stabilizer, 6 g of fatty acid polyglycidyl ether as an epoxy-based crosslinking agent, and 6 g of sodium polyacrylate as a thickening agent were used, the treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the composition for a foamed sheet was 55%, the viscosity was 3900 mPa·s, and the pH was 8.6. The composition for a foamed sheet was foamed 2.3 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.43 g / cm 3 3.

[0137] (Production Example 13) In Production Example 1, a TOCN-Cu aqueous dispersion with a solid content concentration of 0.9% was prepared. Also, 200 g of the above polymer latex (solid content concentration: 58%), 1.3 g of the above TOCN-Cu aqueous dispersion (TOCN-Cu content based on 100 parts by mass of the polymer: 0.01 part by mass), 8 g of ammonium stearate as a foam stabilizer, 6 g of fatty acid polyglycidyl ether as an epoxy-based crosslinking agent, and 6 g of sodium polyacrylate as a thickener were used. The treatment was carried out in the same manner as in Production Example 1 except for the above, to obtain a composition for a foamed sheet. The effective component concentration of the composition for a foamed sheet was 57%, the viscosity was 5000 mPa·s, and the pH was 8.6. The composition for a foamed sheet was foamed 2.3 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.43 g / cm 3 of the foamed composition (foaming liquid).

[0138] (Production Example 14) In Production Example 1, instead of the above TOCN-Cu aqueous dispersion, as a sodium-containing TEMPO-oxidized cellulose nanofiber (TOCN-Na) aqueous dispersion, 24 g of the TEMPO-oxidized cellulose nanofiber aqueous dispersion (solid content concentration: 0.5%) prepared in the section <Preparation of TEMPO-oxidized cellulose nanofiber aqueous dispersion> of Production Example 1 (TOCN-Na content based on 100 parts by mass of the polymer: 0.1 part by mass) and 6 g of sodium polyacrylate as a thickener were used. The treatment was carried out in the same manner as in Production Example 1 except for the above, to obtain a composition for a foamed sheet. The effective component concentration of the composition for a foamed sheet was 51%, the viscosity was 2600 mPa·s, and the pH was 8.8. The composition for a foamed sheet was foamed 3.0 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.31 g / cm 3 of the foamed composition (foaming liquid).

[0139] (Production Example 15) In Production Example 1, a TOCN-Cu aqueous dispersion with a solid content concentration of 0.9% was prepared, and 149 g of the above TOCN-Cu aqueous dispersion (TOCN-Cu content based on 100 parts by mass of the polymer: 1.2 parts by mass), 8 g of ammonium stearate as a foam stabilizer, 6 g of fatty acid polyglycidyl ether as an epoxy-based crosslinking agent, and 6 g of sodium polyacrylate as a thickener were used. Except for this, the treatment was carried out in the same manner as in Production Example 1 to obtain a composition for a foamed sheet. The effective component concentration of the composition for a foamed sheet was 34%, the viscosity was 1300 mPa·s, and the pH was 9.1. The composition for a foamed sheet was foamed 1.7 times using a foaming machine to obtain a foamed composition (foaming liquid) with a density of 0.60 g / cm 3 of the foamed composition (foaming liquid).

[0140] (Example 1) The foaming liquid prepared in Production Example 1 was applied onto synthetic paper (manufactured by Upo Co., Ltd., SDI-80, thickness 80 μm) using an automatic coater (main body: AFA-Standard KT-AB4420 manufactured by TQC sheen Co., Ltd., applicator: Multi Applicator MA-250 manufactured by Coatec Co., Ltd.). The coated synthetic paper was placed in an oven at 80°C (DNF400 manufactured by Yamato Scientific Co., Ltd.) for 80 seconds, and then in an oven at 120°C (DNF400 manufactured by Yamato Scientific Co., Ltd.) for 160 seconds for drying to obtain a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.62 g / cm 3 The strength of the foamed layer, the adhesion to glass, and the air permeability of the laminated sheet were evaluated. The results are shown in Table 1. Also, the deodorizing performance of the laminated sheet against hydrogen sulfide gas and ammonia gas was evaluated. The results are shown in Tables 2 and 3.

[0141] (Example 2) The foaming liquid prepared in Production Example 2 was applied onto synthetic paper (manufactured by Upo Co., Ltd., SDI-80, thickness 80 μm) using an automatic coater (main body: AFA-Standard KT-AB4420 manufactured by TQC sheen Co., Ltd., applicator: Multi Applicator MA-250 manufactured by Coatec Co., Ltd.). The coated synthetic paper was placed in an oven at 80°C for 80 seconds, and then in an oven at 120°C for 160 seconds for drying to obtain a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.55 g / cm 3A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, a deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0142] (Example 3) The foaming liquid prepared in Production Example 3 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was placed in an oven at 80°C for 80 seconds and then in an oven at 120°C for 160 seconds for drying, obtaining a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.62 g / cm 3 A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, a deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0143] (Example 4) The foaming liquid prepared in Production Example 4 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was placed in an oven at 80°C for 80 seconds and then in an oven at 120°C for 160 seconds for drying, obtaining a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.44 g / cm 3 A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, a deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0144] (Example 5) The foaming liquid prepared in Production Example 5 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was placed in an oven at 80°C for 80 seconds and then in an oven at 120°C for 160 seconds for drying, obtaining a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.43 g / cm 3A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, the deodorizing performance of the laminated sheet against hydrogen sulfide gas and ammonia gas was evaluated. The results are shown in Tables 2 and 3.

[0145] (Example 6) The foaming liquid prepared in Production Example 6 was applied onto a PET film (manufactured by Teijin Limited, double-sided easy-adhesion processed G2, thickness 50 μm) using an automatic coater. The coated PET film was placed in an oven at 80°C for 80 seconds, then in an oven at 120°C for 80 seconds, and further in an oven at 140°C (DNF400 manufactured by Yamato Scientific Co., Ltd.) for 80 seconds to dry, obtaining a laminated sheet with a foamed layer thickness of 110 μm and a foamed layer density of 0.35 g / cm 3 A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, the deodorizing performance of the laminated sheet against hydrogen sulfide gas and ammonia gas was evaluated. The results are shown in Tables 2 and 3.

[0146] (Example 7) The foaming liquid prepared in Production Example 6 was applied onto a PET film (manufactured by Teijin Limited, double-sided easy-adhesion processed G2, thickness 50 μm) using an automatic coater. The coated PET film was placed in an oven at 80°C for 80 seconds, then in an oven at 120°C for 80 seconds, and further in an oven at 140°C for 80 seconds to dry, obtaining a laminated sheet with a foamed layer thickness of 150 μm and a foamed layer density of 0.35 g / cm 3 A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, the deodorizing performance of the laminated sheet against hydrogen sulfide gas and ammonia gas was evaluated. The results are shown in Tables 2 and 3.

[0147] (Example 8) The foaming liquid prepared in Production Example 6 was applied onto a PET film (manufactured by Teijin Limited, double-sided easy-adhesion processed G2, thickness 50 μm) using an automatic coater. The coated PET film was placed in an oven at 80°C for 80 seconds, then in an oven at 120°C for 80 seconds, and further in an oven at 140°C for 80 seconds to dry, obtaining a laminated sheet with a foamed layer thickness of 170 μm and a foamed layer density of 0.36 g / cm3 A laminated sheet was obtained. The strength of the foam layer, the adhesion to glass, and the air permeability of the laminated sheet were measured. The results are shown in Table 1. In addition, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was carried out. The results are shown in Tables 2 and 3.

[0148] (Example 9) The foaming liquid prepared in Production Example 6 was applied onto a PET film (manufactured by Teijin Limited, double-sided easy-adhesion processed, thickness 50 μm) using an automatic coater. The coated PET film was put into an oven at 80°C for 80 seconds, then into an oven at 120°C for 80 seconds, and further into an oven at 140°C for 80 seconds for drying, obtaining a laminated sheet with a foam layer thickness of 230 μm and a foam layer density of 0.37 g / cm 3 A laminated sheet was obtained. The strength of the foam layer, the adhesion to glass, and the air permeability of the laminated sheet were measured. The results are shown in Table 1. In addition, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was carried out. The results are shown in Tables 2 and 3.

[0149] (Comparative Example 1) The foaming liquid prepared in Production Example 7 was applied onto a synthetic paper (manufactured by Upo Co., Ltd., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was put into an oven at 80°C for 80 seconds, then into an oven at 120°C for 160 seconds for drying, obtaining a laminated sheet with a foam layer thickness of 120 μm and a foam layer density of 0.57 g / cm 3 A laminated sheet was obtained. The strength of the foam layer, the adhesion to glass, and the air permeability of the laminated sheet were measured. The results are shown in Table 1. In addition, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was carried out. The results are shown in Tables 2 and 3.

[0150] (Comparative Example 2) The unfoamed liquid prepared in Production Example 8 was applied onto a synthetic paper (manufactured by Upo Co., Ltd., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was put into an oven at 80°C for 80 seconds, then into an oven at 120°C for 160 seconds for drying, obtaining an unfoamed layer thickness of 120 μm and an unfoamed layer density of 1.06 g / cm 3A laminated sheet was obtained. The strength of the unfoamed layer of the laminated sheet, the adhesion to glass, and the air permeability were measured. The results are shown in Table 1. Also, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0151] (Comparative Example 3) The foaming liquid prepared in Production Example 9 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was put into an oven at 80°C for 80 seconds, and then into an oven at 120°C for 160 seconds for drying, to obtain a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.78 g / cm 3 A laminated sheet was obtained. The strength of the foamed layer of the laminated sheet, the adhesion to glass, and the air permeability were measured. The results are shown in Table 1. Also, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0152] (Comparative Example 4) The foaming liquid prepared in Production Example 10 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was put into an oven at 80°C for 80 seconds, and then into an oven at 120°C for 160 seconds for drying, to obtain a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.62 g / cm 3 A laminated sheet was obtained. The strength of the foamed layer of the laminated sheet, the adhesion to glass, and the air permeability were measured. The results are shown in Table 1. Also, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0153] (Comparative Example 5) The foaming liquid prepared in Production Example 11 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was put into an oven at 80°C for 80 seconds, and then into an oven at 120°C for 160 seconds for drying, to obtain a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.43 g / cm 3A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, deodorization evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was performed. The results are shown in Tables 2 and 3.

[0154] (Comparative Example 6) The foaming solution prepared in Production Example 12 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was placed in an oven at 80°C for 80 seconds and then in an oven at 120°C for 160 seconds for drying, obtaining a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.40 g / cm 3 A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, deodorization evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was performed. The results are shown in Tables 2 and 3.

[0155] (Comparative Example 7) The foaming solution prepared in Production Example 13 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was placed in an oven at 80°C for 80 seconds and then in an oven at 120°C for 160 seconds for drying, obtaining a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.39 g / cm 3 A laminated sheet was obtained. The foamed layer strength, adhesion to glass, and air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, deodorization evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was performed. The results are shown in Tables 2 and 3.

[0156] (Comparative Example 8) The foaming solution prepared in Production Example 14 was applied onto synthetic paper (manufactured by Upo Co., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was placed in an oven at 80°C for 80 seconds and then in an oven at 120°C for 160 seconds for drying, obtaining a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.32 g / cm 3A laminated sheet was obtained. The foamed layer strength, the adhesion to glass, and the air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0157] (Comparative Example 9) The foaming liquid prepared in Production Example 15 was applied onto synthetic paper (manufactured by Upo Co., Ltd., SDI-80, thickness 80 μm) using an automatic coater. The coated synthetic paper was put into an oven at 80°C for 80 seconds and then into an oven at 120°C for 160 seconds to be dried, obtaining a laminated sheet with a foamed layer thickness of 120 μm and a foamed layer density of 0.60 g / cm 3 A laminated sheet was obtained. The foamed layer strength, the adhesion to glass, and the air permeability of the laminated sheet were measured. The results are shown in Table 1. Also, the deodorizing property evaluation of the laminated sheet against hydrogen sulfide gas and ammonia gas was conducted. The results are shown in Tables 2 and 3.

[0158] [Table 1] [Table 2] [Table 3]

[0159] From the results in Tables 1 to 3, it can be seen that in Examples 1 to 9 using a composition for a foamed sheet containing a polymer and TOCN-Cu as a metal-containing oxidized cellulose nanofiber containing a metal other than sodium in the form of a salt, and the content of TOCN-Cu being 0.1 part by mass or more and 1.00 part by mass or less with respect to 100 parts by mass of the polymer, the adhesion (adsorptivity) to the base material of the laminate and the deodorizing property can be achieved at a high level simultaneously. On the other hand, from the results in Tables 1 to 3, in Comparative Example 1 and Comparative Example 9 where the content of TOCN-Cu with respect to 100 parts by mass of the polymer is 1.30 parts by mass and 1.20 parts by mass, respectively, although the deodorizing property is excellent because a large amount of TOCN-Cu is contained, it can be seen that the adhesion is as low as 0.008 (N / cm) and 0.009 (N / cm), respectively. Further, from the results of Tables 1 to 3, it can be seen that in Comparative Examples 2 to 5 where TOCN-Cu is not used, the self-adhesion is excellent, but the deodorizing property is poor because TOCN-Cu does not exist. Also, from the results of Tables 1 to 3, in Comparative Examples 6 and 7 where the content of TOCN-Cu with respect to 100 parts by mass of the polymer is 0.05 part by mass and 0.01 part by mass, respectively, the self-adhesion is excellent, but it can be seen that the deodorizing property is poor because the content of TOCN-Cu is low. Furthermore, from the results of Tables 1 to 3, in Comparative Example 8 where TOCN-Na is used as the metal-containing oxidized cellulose nanofiber, the self-adhesion is excellent, but it can be seen that the deodorizing property is not sufficient because TOCN-Cu is not used.

Industrial Applicability

[0160] According to the present invention, it is possible to provide a self-adhesive foamed sheet excellent in deodorizing property and adsorbing property, and a composition for a self-adhesive foamed sheet capable of providing the self-adhesive foamed sheet. Also according to the present invention, it is possible to provide a self-adhesive laminate excellent in deodorizing property and adsorbing property, and a method for producing the self-adhesive laminate.

Claims

1. A polymer and a metal-containing oxidized cellulose nanofiber containing at least one selected from the group consisting of silver, zinc, and copper in the form of a salt, wherein the content of the metal-containing oxidized cellulose nanofiber is 0.1 part by mass or more and 1.00 part by mass or less with respect to 100 parts by mass of the polymer, and the polymer contains 60% by mass or more and 99% by mass or less of (meth)acrylate monomer units, unsaturated carboxylic acid monomer units, vinyl cyanide monomer units, and 0.5% by mass or more and 20% by mass or less of alkenyl aromatic monomer units, and is a composition for a self-adhesive foamed sheet.

2. The composition for a self-adhesive foamed sheet according to claim 1, wherein the number average fiber diameter of the metal-containing oxidized cellulose nanofiber is 100 nm or less.

3. The composition for a self-adhesive foamed sheet according to claim 1 or 2, wherein the metal-containing oxidized cellulose nanofiber is a metal-containing carboxylated cellulose nanofiber.

4. A self-adhesive foamed sheet obtained by foaming and forming the composition for a self-adhesive foamed sheet according to any one of claims 1 to 3 into a sheet shape.

5. with a density of 0.3 g / cm ３ or more, the self-adhesive foamed sheet according to claim 4.

6. A self-adhesive laminate comprising a base material and the self-adhesive foamed sheet according to claim 4 or 5.

7. A step of preparing the composition for a self-adhesive foamed sheet according to any one of claims 1 to 3, a step of foaming the composition for a self-adhesive foamed sheet to obtain a foamed composition, and a step of forming the foamed composition into a sheet shape on a base material, and is a method for producing a self-adhesive laminate.

Images