JP2013079454A - Functional foamed wall paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide foamed wall paper that has superior performance capable of diffusing or reflecting a light beam, that is, has high diffuseness and reflectiveness.SOLUTION: The foamed wall paper comprises a substrate, a foamed resin layer and a light diffusion and reflective layer, in this order. The light diffusion and reflective layer is a cured material of a resin composition that contains a light diffusing agent and a curable resin so that a mass ratio (P/V) of a content P of the light diffusing agent to a content V of the curable resin becomes 3.5 to 5.5.

Description

  The present invention relates to a functional foam wallpaper.

In recent years, there has been a growing trend toward energy conservation in connection with the reduction of CO ₂ emissions to suppress global warming. Furthermore, with the revision of the criteria for determining whether nuclear power plants can be operated, there is a tendency for power supply to become insufficient nationwide, so energy conservation is a particularly important issue. In order to realize energy saving, energy saving due to housing cannot be ignored along with energy saving in the field of industrial equipment. To save energy in living spaces, methods such as air-conditioning, televisions, refrigerators, etc., which are used daily, such as household appliances and light bulbs, are made energy-saving, or the temperature settings of air conditioners and refrigerators are adjusted. Yes.

By the way, when attention is paid to the interior material from the viewpoint of a member that can promote energy saving in the living space, a wall surface and a ceiling are mentioned as the interior material that occupies the most area. In general, architectural interior materials such as wallpaper are required to have high design properties in order to enhance comfort as indoor living spaces, and in particular, foamed wallpaper is employed to provide a three-dimensional design (for example, Patent Document 1). However, the reflectance of foamed wallpaper used in the past is as high as about 80% for light-colored wallpaper, and about 85% for white-colored wallpaper without pattern. When hit, about 20% of the light was absorbed or transmitted by the wallpaper.
If we can provide products with higher diffuse reflectance than conventional foam wallpaper for walls and ceilings, such as walls and ceiling wallpaper with higher diffuse reflectance, the interior of the room can be reduced even with less sunlight and lighting. Can be brightened. As a result, it is possible to reduce the power consumption of the room lighting or to reduce the number of room lighting, and as a result, it is considered to lead to energy saving.

JP 2001-260287 A

  The present invention provides a foam wallpaper having an ability to diffuse or reflect an excellent light beam, that is, a high diffuse reflectance.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the problem can be solved by the following invention. The gist of the present invention is as follows.

1. 2. A substrate, a foamed resin layer, and a light diffusing and reflecting layer are provided in this order, and the light diffusing and reflecting layer has a mass ratio (P / V) of the content P of the light diffusing agent and the content V of the curable resin. A foam wallpaper which is a cured product of a resin composition containing a light diffusing agent and a curable resin so as to be 5 to 5.5.
2. 2. The foamed wallpaper according to 1 above, wherein the non-foamed resin layer A is provided between the substrate and the foamed resin layer.
3. 3. The foamed wallpaper as described in 1 or 2 above, wherein the non-foamed resin layer B is provided between the foamed resin layer and the light diffusion reflection layer.
4). 4. The foamed wallpaper according to any one of the above 1 to 3, further comprising a surface protective layer on the light diffusive reflective layer.
5. 5. The foamed wallpaper according to any one of 1 to 4 above, wherein the surface has an uneven pattern.

    According to the present invention, it is possible to obtain a foamed wallpaper having excellent performance of diffusing or reflecting light rays, that is, high diffuse reflectance.

It is a schematic diagram which shows the cross section of one form of the foam wallpaper of this invention. It is a schematic diagram which shows the cross section of one preferable form of the foam wallpaper of this invention.

The foamed wallpaper of the present invention has a base material, a foamed resin layer, and a light diffusing and reflecting layer in order, and the light diffusing and reflecting layer is a mass ratio of the content P of the light diffusing agent and the content V of the curable resin ( P / V) is a cured product of a resin composition containing a light diffusing agent and a curable resin so as to be 3.5 to 5.5. FIG. 1 is a schematic diagram showing a cross section of one embodiment of the foam wallpaper of the present invention, in which a foam wallpaper 1 having a base material 2, a foam resin layer 4, and a light diffusion reflection layer 5 in this order is shown. FIG. 2 is a schematic diagram showing a cross-section of a preferred embodiment of the foamed wallpaper of the present invention. The substrate 2, the non-foamed resin layer 3A, the foamed resin layer 4, the non-foamed resin layer 3B, the light diffusing reflective layer 5, A foam wallpaper 1 having a pattern layer 6 and a surface protective layer 7 in this order and having a concavo-convex pattern 8 on its surface is shown.
Hereinafter, the configuration of the foam wallpaper according to the present invention will be described in detail with reference to FIGS.

[Substrate 2]
The base material is not particularly limited as long as it is usually used as wallpaper. For example, backing paper, flame retardant paper, synthetic resin sheet, woven fabric, non-woven fabric, knitted fabric and the like can be appropriately selected depending on the application. . Among them, wallpaper such as pulp-based flame retardant paper impregnated with water-soluble flame retardants such as guanazine sulfanilate and guanazine phosphate, or inorganic paper mixed with inorganic agents such as calcium carbonate, aluminum hydroxide, magnesium hydroxide, etc. A backing paper or a backing material using the same is preferably used.
From the viewpoint of curling prevention, the backing paper preferably has an underwater elongation of 2% or less, and more preferably 1.8% or less. Incidentally, the elongation in water is determined by the JAPAN TAPPI paper pulp test method No. It is a value measured according to 27: 2000.

  These materials may be used alone, but may be a laminate of any combination, such as a composite of papers, and if necessary, flame retardant, inorganic agent, dry paper strength enhancer, Additives such as a wet paper strength enhancer, a colorant, a sizing agent, and a fixing agent may be appropriately added.

[Foamed resin layer 4]
The foamed resin layer is a layer that imparts three-dimensional design as well as flame retardancy to the foamed wallpaper of the present invention. The foamed resin layer is usually a layer formed of a foamed resin composition containing a foaming agent and a resin component.

(Resin component)
As a resin component contained in a foamed resin composition, an olefin resin, an acrylic resin, etc. are mentioned preferably, These are independent and can be employ | adopted combining several resin.
The olefin resin includes not only a homopolymer of olefin and a copolymer of two or more olefins but also a copolymer of an olefin component and another monomer component.
Preferred examples of the olefin resin include ethylene resin, propylene resin, butene resin, pentene resin, and the like, and ethylene resin is more preferably employed in the present invention.
Examples of ethylene resins include ethylene homopolymers, ethylene-vinyl alcohol copolymers, ethylene-vinyl acetate copolymers, copolymers of ethylene and unsaturated carboxylic acids, and ethylene and unsaturated carboxylic esters. Copolymers such as ethylene- (meth) acrylic acid copolymer, ethylene-methyl (meth) acrylate copolymer, ethylene-ethyl (meth) acrylate copolymer resin, ethylene having 3 to 5 carbon atoms Preferred are ethylene- (meth) acrylic acid copolymers such as-(meth) acrylic acid alkyl copolymers. The olefin resin may be used alone or in combination of two or more.

Among these, an ethylene-vinyl alcohol copolymer, an ethylene-vinyl acetate copolymer, and an ethylene- (meth) acrylic acid-based copolymer are preferable, and an ethylene-vinyl acetate copolymer, an ethylene- (meth) acrylic acid are preferable. Copolymers and ethylene- (meth) methyl acrylate copolymers are preferred. These resins impart excellent surface properties such as stain resistance, scratch resistance, and chemical resistance to foamed wallpaper, and have excellent unevenness followability in embossing, for example. Therefore, the manufacturing cost is low, the smoke density at the time of combustion is small, and this is preferable from the viewpoint of environmental protection.
In the ethylene-vinyl acetate copolymer, the vinyl acetate component (VA component) is preferably 5 to 30% by mass, more preferably 10 to 30% by mass, and still more preferably 15 to 25% by mass. In addition, in the ethylene- (meth) acrylic acid copolymer, the (meth) acrylic acid component is preferably 3 to 30% by mass, more preferably 5 to 20% by mass, and further preferably 5 to 15%. % By mass.

  An acrylic resin is a resin containing a (meth) acrylic acid component, and a homopolymer of (meth) acrylic acid or its ester which is a (meth) acrylic acid component or a co-polymer of two or more types of (meth) acrylic acid components. Also included are copolymers and copolymers of (meth) acrylic acid components with other monomer components. For example, in addition to homopolymer resins of alkyl (meth) acrylates such as methyl (meth) acrylate resin and ethyl (meth) acrylate resin, copolymers having other monomer components as olefins such as ethylene and Preferred are a copolymer with a saturated carboxylic acid, a copolymer of ethylene and an unsaturated carboxylic acid ester, specifically, for example, an ethylene- (meth) acrylic acid copolymer. An acrylic resin may be used independently and may mix and use 2 or more types.

  Moreover, the melt flow rate value (MFR) of the resin component used for the foamed resin layer is not particularly limited, but is preferably about 5 to 80 g / 10 minutes.

(Foaming agent)
Examples of the foaming agent contained in the foamed resin composition include inorganic foaming agents such as sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, and ammonium nitrite; N, N′-dimethyl-N, N′-dinitrosotephthalamide Nitroso compounds such as N, N′-dinitrosopentamethylenetetramine; azo compounds such as azodicarbonamide, azobisformamide, azobisisobutyronitrile, azocyclohexylnitrile, azodiaminobenzene, barium azodicarboxylate; Sulfonyl hydrazide compounds such as benzenesulfonyl hydrazide, toluenesulfonyl hydrazide, p, p′-oxybis (benzenesulfonyl hydrazide), diphenylsulfone-3,3′-disulfonyl hydrazide, calcium azide, 4, '- diphenyl azide, azide compounds such as p- toluenesulfonyl azide, and the like preferably.
Low cost, low heat of decomposition, excellent flame retardancy and self-extinguishing properties, stable in water, non-toxic, and capable of processing heat decomposition chemical foaming agent below decomposition temperature Therefore, a thermally decomposable foaming agent of an azo compound such as azodicarbonamide or azobisformamide is preferable.

The addition amount of the foaming agent may be appropriately determined depending on the required design properties, but is preferably 0.5 to 15 parts by mass with respect to 100 parts by mass of the resin component.
In the present invention, if necessary, a foaming aid that accelerates the decomposition of the foaming agent can be used in combination in order to obtain a further foaming effect. For example, when azodicarbonamide is used as the foaming agent, zinc oxide, lead sulfate, urea, zinc stearate, or the like is used as the foaming aid.

(Inorganic filler)
The foamed resin composition can preferably contain an inorganic filler for the purpose of imparting flame retardancy to the foamed wallpaper. There is no restriction | limiting in particular as an endless filler, Various things can be used. For example, calcium carbonate, magnesium carbonate, fly ash, dehydrated sludge, natural silica, synthetic silica, kaolin, clay, calcium oxide, magnesium oxide, titanium oxide, zinc oxide, barium sulfate, calcium hydroxide, aluminum hydroxide, alumina, water Magnesium oxide, talc, mica, hydrotalcite, aluminum silicate, magnesium silicate, calcium silicate, calcined talc, wollastonite, potassium titanate, magnesium sulfate, calcium sulfate, magnesium phosphate, sepiolite, zonolite, aluminum borate, silica Balloons, glass flakes, glass balloons, silica, iron slag, copper, iron, iron oxide, carbon black, sendust, alnico magnets, magnetic powders such as various ferrites, cement, glass powder, diatomaceous earth Antimony trioxide, magnesium oxysulfate, hydrated aluminum, hydrated gypsum, such as alum are preferably exemplified.
Among these, aluminum hydroxide is preferable because it has a low decomposition temperature, a large endothermic amount, and low cost. These inorganic fillers can be used alone or in combination of two or more.

The inorganic filler has an effect of imparting flame retardancy to the foamed wallpaper, and the effect is further increased when added in a large amount. The amount of the inorganic additive used is preferably 15 parts by mass or more and preferably 80 parts by mass or more with respect to 100 parts by mass of the resin component for the purpose of sufficiently obtaining the flame retardancy of the foam wallpaper. 100 parts by mass or more is more preferable.
The average particle diameter of the inorganic filler is preferably 5 to 25 μm, more preferably 5 to 15 μm, from the viewpoint of efficiently obtaining the effect of adding the inorganic filler.

  These inorganic fillers may be used as they are, but the inorganic fillers are previously silane-based, titanate-based, aluminate-based, zircoaluminum-based coupling agents, phosphate-based, fatty acid-based surfactants, You may process by fats and oils, wax, a stearic acid, a silane coupling agent, etc.

  Moreover, the foamed resin composition can contain various additives according to the required physical properties. Examples of various additives include flow modifiers, fungicides, insecticides, antiseptics, antibacterial agents, diluents, deodorants, light stabilizers, plasticizers, and the like.

(Formation of foamed resin layer)
A foamed resin layer is formed through the process of forming an unfoamed resin layer using said foamed resin composition, and the process of foaming this unfoamed resin layer.
The non-foamed resin layer is formed by, for example, converting the above foamed resin composition into an emulsion composition by emulsifying, or pelletizing a comma coater method, an extrusion film forming method using a T-die, or a calendar film forming. And a known method such as a dry lamination method using an adhesive. Here, emulsification can be carried out by a conventional method, and the emulsion composition is obtained, for example, by emulsifying the resin component in the foamed resin composition by an emulsion polymerization method or the like and then adding a predetermined amount of other components.

When the extrusion film forming method using a T-die is adopted, the formation of the non-foamed resin layer A or the non-foamed resin layer B and the non-foamed resin layer provided as desired may be performed separately or simultaneously. Good. In the case of simultaneous extrusion film formation, a multi-manifold type T die or the like that enables simultaneous formation of a plurality of layers by simultaneously forming a molten resin corresponding to each layer.
In addition, when an extrusion film forming method using a T-die is employed for forming the unfoamed resin layer, the inorganic filler preferably contained in the foamed resin composition tends to remain in the extrusion port (so-called die) of the extruder, Inorganic filler residues (so-called eyes and eyes) tend to become foreign matters on the sheet surface. In such a case, it is preferable to provide both the non-foamed resin layers A and B. With such a configuration, it is possible to suppress the occurrence of eye spots by simultaneously forming the non-foamed resin layer between the two non-foamed resin layers 3A and 3B, and excellent manufacturing stability is achieved. can get.

The foamed resin composition may be subjected to a crosslinking treatment for the purpose of improving the surface characteristics. The method for the crosslinking treatment is not limited, and for example, a crosslinking treatment (curing treatment) with ionizing radiation is preferably mentioned. For example, a layer made of a foamed resin composition is formed on a base material or a non-foamed resin layer provided as desired, and cross-linked by irradiation with ionizing radiation such as an electron beam or ultraviolet rays. As a result, productivity is stabilized, and the surfaces of the non-foamed resin layers A and B provided as desired as well as the foamed resin layer are hardened, and the surface characteristics of the foamed wallpaper are improved. Irradiation with ionizing radiation can be appropriately performed before or after foaming the foamed resin composition. From the viewpoint of easy treatment, it is preferable to perform a crosslinking treatment in the state of the unfoamed resin layer before foaming.
When the foamed resin composition is subjected to a crosslinking treatment, the foamed resin composition can preferably contain a crosslinking agent. Any crosslinking agent can be used without particular limitation as long as it can crosslink the resin component in the foamed resin composition.

The ionizing radiation used for the cross-linking treatment means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing or cross-linking molecules, and usually ultraviolet rays (UV) or electron beams (EB) are used. In addition, electromagnetic waves such as X-rays and γ rays, and charged particle beams such as α rays and ion rays are also included.
As the ultraviolet light source, for example, a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a black light lamp, or a metal halide lamp can be used. Further, as the electron beam source, for example, various electron beam accelerators such as a Cockloft Walton type, a pandegraph type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type may be used. The irradiation dose is usually selected in the range of 5 to 300 kGy (0.5 to 30 Mrad), preferably 10 to 50 kGy (1 to 5 Mrad).

The unfoamed resin layer can be foamed by a known foaming method, and can be foamed at a temperature of about 180 to 240 ° C. using, for example, a foaming heating furnace. The foaming treatment can be performed without particular limitation as long as the foamed resin composition is formed as an unfoamed resin layer, but may be usually performed after the light diffusive reflection layer is provided.
The thickness of the foamed resin layer is not particularly limited and can be appropriately set according to desired characteristics, etc., but the thickness of the unfoamed resin layer is preferably 50 to 300 μm, and the foamed resin after foaming The thickness of the layer is preferably 350 to 1200 μm. Moreover, the expansion ratio in forming the foamed resin layer may be usually about 3 to 7 times. When the expansion ratio is within the above range, good surface strength, workability, and the like can be obtained.

[Non-foamed resin layers 3A, 3B]
The foamed wallpaper is for the purpose of improving the interlayer adhesion between the base material and the foamed resin layer, or for the purpose of suppressing the penetration of the material forming each layer into the base material via the foamed resin layer. Thus, in order to obtain manufacturing stability when an extrusion film forming method using a T-die is employed for forming the unfoamed resin layer, a non-foamed resin layer is preferably included.
In the present invention, the non-foamed resin layer that is preferably provided between the base material and the foamed resin layer to improve the interlayer adhesion between the two layers is referred to as a non-foamed resin layer A, and the material forming each layer is a foamed resin. The non-foamed resin layer that is preferably provided between the foamed resin layer and the light diffusive reflective layer is referred to as a non-foamed resin layer B for the purpose of suppressing permeation into the substrate via the layer. In the present invention, it is preferable to have at least one of the non-foamed resin layers A and B, and considering the production stability while obtaining the performance of the non-foamed resin layers A and B, the non-foamed resin layers A and B It is preferable to have both.

(Resin component)
The non-foamed resin layers A and B are composed of a resin composition containing a resin component and various additives added according to desired performance.
There is no restriction | limiting in particular as a resin component, For example, various copolymers by the thermoplastic resin single-piece | units, such as an olefin resin, an acrylic resin, a thermoplastic polyester resin, a polyvinyl alcohol resin, a fluororesin, and the structural unit which forms the said resin are mentioned. be able to. Of these, olefin resins and acrylic resins are preferred.
As the olefin resin, those exemplified as the resin component used in the foamed resin layer are preferably exemplified, and among them, ethylene-vinyl alcohol copolymer, ethylene-vinyl acetate copolymer, or ethylene and unsaturated carboxyl It is the same as that of the resin component used for a foamed resin layer that the copolymer with an acid, the copolymer of ethylene and unsaturated carboxylic acid ester, especially an ethylene- (meth) acrylic acid type copolymer are preferable. Moreover, as an acrylic resin, the thing similar to what was illustrated as a resin component used for a foamed resin layer is illustrated preferably.

(Various additives)
As various additives added to the resin composition constituting the non-foamed resin layers A and B according to desired performance, an inorganic filler for imparting a bulking effect, a flame retardant for imparting flame retardancy Etc. can be preferably employed.
As an inorganic filler, the inorganic filler used for said foamed resin layer is illustrated preferably.
Suitable flame retardants include, for example, nitrogen compounds such as urea, hydroxides such as magnesium hydroxide and aluminum hydroxide (particularly compounds having crystal water), flame retardants containing phosphorus or halogen elements having self-extinguishing properties, and the like. A mixed flame retardant compound composed of a nitrogen compound and a phosphorus compound is preferred. The usage-amount of a flame retardant is about 25-100 mass parts normally with respect to 100 mass parts of resin components. This is because the compatibility with the resin component is good and the thermal stability is also good.

Various rubbers can also be added to the non-foamed resin layer for the purpose of imparting flexibility, impact resistance, and easy adhesion. Preferred examples of rubbers include diene rubbers, hydrogenated diene rubbers, and olefin elastomers. Among these, hydrogenated diene rubbers are preferable. A hydrogenated diene rubber is formed by adding a hydrogen atom to at least a part of a double bond of a diene rubber molecule. In the present invention, the hydrogenated diene rubber is used as a resin component modifier and suppresses crystallization of the resin component. Have the role of increasing flexibility and transparency.
In this invention, it is preferable that the addition amount of rubber | gum shall be about 1-90 mass parts normally with respect to 100 mass parts of resin components.

  Moreover, a pigment can be added and transparent coloring or opaque coloring can also be given. As the pigment, known or commercially available pigments can be used without limitation. For example, titanium white, zinc white, petal, vermilion, ultramarine blue, cobalt blue, titanium yellow, yellow lead, carbon black and other inorganic pigments, isoindolinone, Hansa Yellow A, quinacridone, permanent red 4R, phthalocyanine blue, indanthrene Examples thereof include organic pigments (including dyes) such as Brie RS and aniline black, metal pigments such as aluminum and brass, pearlescent pigments made of foil powder such as titanium dioxide-coated mica and basic lead carbonate, and the like. These can select either a transparent colored pigment or an opaque colored pigment depending on the application. These pigments may be added and dispersed as powder or scaly foil pieces.

  The non-foamed resin layers A and B are not particularly limited as long as they are composed of the resin composition as described above, and may be formed of the same material or different materials. What is necessary is just to judge suitably according to performance. The thicknesses of these layers may be the same or different and may be appropriately selected according to the desired performance.

(Formation of non-foamed resin layer)
The non-foamed resin layers A and B were obtained by using the above-mentioned non-foamed resin composition in the same manner as the non-foamed resin layer of the above-mentioned foamed resin layer, that is, emulsified into an emulsion composition, or pelletized. The product can be formed by a known method such as a comma coater method, an extrusion film forming method using a T-die, a calendar film forming method, or a dry lamination method using an adhesive. When adopting an extrusion film forming method using a T-die, the inorganic filler residue that is preferably contained in the foamed resin composition is reduced in defects that remain on the die and become a foreign substance on the sheet surface, that is, excellent production stability. In order to improve the performance, it is preferable to provide the non-foamed resin layers A and B, and simultaneously form the two layers by sandwiching the non-foamed resin layer.
Moreover, it is the same as said foamed resin layer that you may give a crosslinking process in order to improve a surface characteristic.

The non-foamed resin layers A and B can also be formed using a transparent or opaque commercially available film made of the above resin component.
The thickness of the non-foamed resin layers A and B is preferably 3 to 50 μm, more preferably 3 to 20 μm, for the purpose of obtaining excellent surface characteristics and ensuring the unevenness followability of the wallpaper by embossing. Preferably it is 5-15 micrometers. Moreover, if it is in the said range, there will be no restrictions on manufacture of a film.

[Light Diffuse Reflective Layer 5]
The light diffusive reflective layer is a layer that imparts excellent light diffusing or reflecting performance to the foamed wallpaper of the present invention, that is, a layer that imparts high diffuse reflectivity, and is a resin containing a light diffusing agent and a curable resin at a predetermined content. It is a layer formed by a cured product of the composition.

(Resin composition)
The resin composition forming the light diffusing reflection layer contains a light diffusing agent and a curable resin, and the mass ratio (P / V) of the content P of the light diffusing agent and the content V of the curable resin is 3 It is a resin composition containing so that it may become 0.5-5.5. If the mass ratio (P / V) is less than 3.5, good high diffuse reflectance cannot be obtained, and if it exceeds 5.5, sufficient interlayer adhesion between the light diffuse reflection layer and other layers can be obtained. In addition, the applicability of the resin composition is significantly reduced. From such a viewpoint, the mass ratio (P / V) between the content P of the light diffusing agent and the content V of the curable resin is preferably 3.5 to 4.5.

  As the light diffusing agent, conventionally known agents can be used as the light diffusing agent, and preferred examples include white pigments such as titanium oxide, barium sulfate, magnesium sulfate, silicon oxide, magnesium carbonate, calcium carbonate, and zinc oxide. These can be used alone or in combination. Among these, titanium oxide having a high refractive index and being inexpensive is more preferable.

  The titanium oxide used in the present invention is required to have a quality of 75 to 90%. Preferably it is 78-90%, More preferably, it is 78-85%. As the titanium oxide used for the white pigment, a titanium oxide usually having a grade of more than 90% and close to 100% is selected, but in the present invention, a titanium oxide in a region that is not too high is used. By using titanium oxide in such a region, the color tone is settled and excellent diffuseness and high diffuse reflectance can be obtained. Here, the quality of titanium oxide is the content of titanium oxide measured by the metal aluminum reduction method or the zinc amalgam method for the titanium oxide used in the present invention, that is, the purity of titanium oxide.

Further, as the titanium oxide, those whose particle surface of the titanium oxide is untreated or surface-treated can be used, and the ease of application of the resin composition containing the titanium oxide, that is, applicability. In consideration, surface-treated titanium oxide is preferable.
Preferred examples of the surface-treated titanium oxide include those that have been surface-treated with an inorganic metal hydrous oxide and the surface covered with inorganic hydrous oxide fine particles. Preferred examples of the inorganic metal-containing oxide include alumina, silica and titania, as well as zirconia, tin oxide, antimony oxide and zinc oxide. In addition, titanium oxide whose surface has been untreated or treated with the above inorganic metal hydrous oxide, a coupling agent such as a silane coupling agent, a titanate coupling agent, an aluminum coupling agent, or a silicone oil, A surface treatment with a fluorinated oil or the like to make the surface hydrophobic or lipophilic is also preferred. In addition, surface treatment with organic chemicals such as polyols such as pentaerythritol and trimethylolpropane, alkanolamines such as organic acid salts of triethanolamine and trimethylolamine, silicon resins such as silicon resins and alkylchlorosilanes, etc. Titanium is also preferred. In the present invention, the above surface treatments can be employed alone or in combination with a plurality of surface treatments.
In the present invention, from the viewpoint of obtaining high diffuse reflectivity, surface treatment with alumina, silica, and zinc oxide is preferable among the above, and surface treatment with alumina and silica is more preferable, and in particular, alumina / silica surface treatment (alumina and silica). Surface treatment) is preferred for both.

Titanium oxide has anatase type, rutile type and brookite type depending on the crystal form. From the viewpoint of availability, anatase type and rutile type are preferable, and rutile type (refractive index of 2.71) compared to anatase type (refractive index of 2.52). ) Has a high refractive index and a higher diffuse reflectivity is obtained, the rutile type is more preferable.
The average particle diameter of titanium oxide is usually about 0.05 to 3 μm, preferably 0.05 to 1 μm, more preferably 0.1 to 0.8 μm. When the average particle size of the titanium oxide is within the above range, high diffuse reflectance can be obtained, and good application suitability of the resin composition can be obtained. Here, the average particle diameter of titanium oxide is a value calculated by measuring individual particle diameters from an electron beam microscope and averaging the particle diameters.

(Curable resin)
Preferred examples of the curable resin include polyester resins, acrylic resins, urethane resins, copolymers of constituent units of these resins, and mixtures of these resins. Among these, from the viewpoint of obtaining interlayer adhesion between the light diffusion reflection layer and other layers, a copolymer of a polyester resin constituent unit and an acrylic resin constituent unit is preferable. That is, a copolymer of a polyvalent carboxylic acid and a polyhydric alcohol, which are constituent units of a polyester resin, and (meth) acrylic acid or an ester thereof which is a (meth) acrylic acid component (constituent unit) of an acrylic resin, is more preferable. Is a polyester-acrylic copolymer in which the hydroxyl group of a polyester oligomer having a hydroxyl group at both ends obtained by condensation of a polycarboxylic acid and a polyhydric alcohol is esterified with a (meth) acrylic acid component. Is preferable because it is inexpensive and inexpensive.
Further, from the viewpoint of obtaining better interlayer adhesion, it is preferable to use a mixture of the above polyester-acrylic copolymer and urethane resin as the curable resin. It is preferable that content of the urethane resin in this mixture is 5-50 mass%, More preferably, it is 10-35 mass%, More preferably, it is 15-25 mass%. When the content of the urethane resin is within the above range, excellent interlayer adhesion can be obtained.

  The thickness of the light diffuse reflection layer is preferably 1 to 20 μm, more preferably 2 to 15 μm, and further preferably 3 to 10 μm. When the thickness is within the above range, high diffuse reflectivity can be obtained, surface characteristics such as contamination resistance can be improved, and interlayer adhesion between the light diffuse reflection layer and other layers can be improved.

[Surface protective layer 7]
The foamed wallpaper of the present invention preferably has a surface protective layer from the viewpoint of improving surface properties such as stain resistance, scratch resistance, and chemical resistance. The surface protective layer is preferably made of a cured product of a curable resin composition containing a curable resin and various additives added as necessary.

(Curable resin)
Preferred examples of the curable resin contained in the curable resin composition include polyurethane resins, epoxy resins, vinyl resins, polyester resins, and acrylic resins. Also, various forms such as water-based, emulsion-based, solvent-based and solvent-free systems can be used, and a one-component curable type, a two-component curable type using a curing agent, and the like can be used. Among these, since a surface protective layer can be easily formed, a one-component curable resin is preferable, and among them, an acrylic resin capable of obtaining excellent surface properties is preferable.

In addition, an ionizing radiation curable resin that is cured by an active energy ray such as an ultraviolet ray or an electron beam can be used. As the ionizing radiation curable resin, it can be appropriately selected from conventionally used polymerizable monomers, polymerizable oligomers or prepolymers.
As the polymerizable monomer, a (meth) acrylate monomer having a radically polymerizable unsaturated group in the molecule is suitable, and in particular, a polyfunctionality having two or more ethylenically unsaturated bonds in the molecule ( A (meth) acrylate monomer is preferable, and one kind may be used alone, or two or more kinds may be used in combination. As a functional group number, 2-8 are preferable, 2-6 are more preferable, and 3-4 are more preferable.
Next, as the polymerizable oligomer, an oligomer having a radical polymerizable unsaturated group in the molecule, for example, urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, polyether (meth) acrylate And oligomers such as acrylic (meth) acrylate, polycarbonate (meth) acrylate, acrylic silicone (meth) acrylate, and caprolactone urethane (meth) acrylate. Among these oligomers, polyfunctional polymerizable oligomers are preferable, and the number of functional groups is preferably 2 to 16, more preferably 2 to 8, and still more preferably 2 to 6.

  Moreover, the curable resin composition which forms a surface protective layer can mix | blend various additives according to the desired physical property of the cured resin layer obtained. Examples of various additives include weather resistance improvers such as UV absorbers and light stabilizers, wear resistance improvers, polymerization inhibitors, crosslinking agents, infrared absorbers, antistatic agents, adhesion improvers, and leveling. Preferable examples include agents, thixotropic agents, coupling agents, plasticizers, antifoaming agents, fillers, solvents, coloring agents, and matting agents. These additives can be appropriately selected from those commonly used.

[Picture layer 6]
The pattern layer is a layer that is preferably provided to give a decorative property to the foamed wallpaper of the present invention, and is provided between the foamed resin layer and the light diffusive reflective layer, or between the light diffusive reflective layer and the surface protective layer provided as desired. It is done. The pattern layer is formed by printing various patterns using an ink composition and a printing machine. For example, gravure printing, offset printing, silk screen printing, and transfer printing from a transfer sheet are known printing methods. Can be formed with ink.
Patterns include stone patterns that simulate the surface of rocks such as wood grain patterns, marble patterns (for example, travertine marble patterns), fabric patterns that simulate cloth and cloth-like patterns, tiled patterns, brickwork patterns, There are also patterns such as marquetry and patchwork that combine these. These patterns are formed not only by multicolor printing with normal yellow, red, blue and black process colors, but also by multicolor printing performed by preparing individual color plates constituting the pattern. .

As the ink composition used for forming the picture layer, a binder, a colorant such as a pigment or a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, or a curing agent is appropriately mixed. There is no restriction | limiting in particular as this binder, For example, it is preferable to use a polyurethane resin, a vinyl acetate resin, an acrylic resin, a polyester resin, a cellulose resin, a polyamide resin etc. individually by 1 type or in mixture of 2 or more types.
Colorants include carbon black (black), iron black, titanium white, antimony white, yellow lead, titanium yellow, petal, cadmium red, ultramarine, cobalt blue and other inorganic pigments, quinacridone red, isoindolinone yellow, phthalocyanine Organic pigments or dyes such as blue, metal pigments made of scaly foil pieces such as aluminum and brass, pearlescent pigments made of scaly foil pieces such as titanium dioxide-coated mica and basic lead carbonate, and the like are used.
The thickness of the pattern layer is preferably about 1 to 20 μm.

(Uneven pattern 8)
The foamed wallpaper preferably has a concavo-convex pattern 8 in order to have excellent design properties. In general, when trying to obtain high diffuse reflectivity, the color tone may be too white to exhibit a design that does not settle down, and these performances are contradictory. However, according to the present invention, the synergistic effect of the concavo-convex pattern and the above light diffusive reflective layer, together with high diffuse reflectivity, the wallpaper color tone is not too white to be settled, and the excellent design with a calm color tone Sex is obtained.
The concavo-convex pattern may be of a level that naturally forms in the outermost layer by foaming of the foamed resin layer, or when the wallpaper in the manufacturing process is at a temperature that can be embossed by any means. Alternatively, it may be formed by applying heat and pressure using an embossed plate or the like from the upper surface of the light diffusing / reflecting layer or the surface protective layer provided if desired, that is, the outermost layer side. From the viewpoint of obtaining an excellent design with a calm color tone, it is preferably a concavo-convex pattern actively formed using an embossed plate or the like.
For the formation of the concavo-convex pattern, a well-known sheet or rotary embossing machine is preferably used. The shape of the concavo-convex pattern includes a wood grain plate groove, stone surface unevenness, cloth surface texture, satin, sand, hairline, There are many line grooves.

[Production method]
The foamed wallpaper of the present invention is manufactured, for example, by the following manufacturing method, but is not limited thereto.
On the base material, the resin composition for forming the foamed resin layer is applied, and the resin composition for forming the light diffusion reflection layer is applied to form an unfoamed resin layer. Here, when the non-foamed resin layer A is formed as desired, the resin composition for forming the resin layer A is applied before application of the resin composition for forming the foamed resin layer, that is, on the unfoamed resin layer. When the non-foamed resin layer B is formed, the resin composition for forming the resin layer B may be applied and formed after the unfoamed resin layer is formed. In addition, two-layer lamination of non-foamed resin layer A / non-foamed resin layer, non-foamed resin layer / non-foamed resin layer B, etc. by the extrusion film forming method using a multi-manifold type T die that enables simultaneous formation of a plurality of layers A three-layer laminate of non-foamed resin layer A / unfoamed resin layer / non-foamed resin layer B can be formed simultaneously. In this case, the two-layer laminate or the three-layer laminate may be laminated on the substrate by thermal lamination or the like. Further, if necessary, an unfoamed resin layer and unfoamed resin layers A and B provided as desired can be cured by irradiation with ionizing radiation such as an electron beam or ultraviolet rays.
Next, after forming a picture layer as desired, a resin composition for forming a light diffusive reflection layer is applied, and a resin composition for forming a surface protective layer is further applied as desired to obtain a laminate. . Then, the foamed resin layer is formed by foaming the unfoamed resin layer at about 220 to 250 ° C. using a heating foaming furnace, and a foamed wallpaper having a concavo-convex pattern on the surface can be obtained by embossing or the like as desired. .

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited at all by this example.

(Evaluation method)
(1) Evaluation of reflectance For the foamed wallpaper obtained in the examples and comparative examples, using a spectrocolorimeter ("CM-3700d (model number)", manufactured by Konica Minolta Co., Ltd.), an incident angle of 8 ° and a wavelength of 550 nm The reflectance at was measured.
(2) Evaluation of Adhesiveness of Light Diffuse Reflecting Layer The foamed wallpaper obtained in Examples and Comparative Examples was attached to a fixed flat table with double-sided tape, and cellophane tape (Nichiban) was applied on the surface of the foamed wallpaper. A cellophane adhesive tape, “Cellotape (registered trademark)” manufactured by Co., Ltd., is attached, and the length of the tape is quickly pulled to the front of the 60 ° direction and peeled off. The state of was evaluated according to the following criteria.
○: The constituent layer was not peeled off from the wallpaper surface at all, or the wallpaper itself was broken. Δ: The constituent layer was peeled off slightly from the wallpaper surface, but there was no problem in practical use. ) Evaluation of stain resistance Applying pollutants (neutral detergent, soy sauce, coffee, crayon, water-based pen) to the foamed wallpaper obtained in Examples and Comparative Examples, and using water and neutral detergent after standing for 24 hours Wiped off. The appearance of the surface of the wallpaper after wiping was visually observed and evaluated according to the following criteria.
○: Dirt was not confirmed. △: Dirt was confirmed slightly, but there was no problem in practical use. X: Remarkable stain was confirmed. (4) Evaluation of brightness (designability) Obtained in Examples and Comparative Examples. About the foamed wallpaper, the desktop fluorescent lamp (27W) was used as a light source, and the design properties compared with the wallpaper having no light diffusion reflection layer obtained in Comparative Example 1 were evaluated according to the following criteria.
○: It is clearly bright but has a subdued color tone △: It feels a little bright or has a subdued color tone ×: No change in brightness or too white color

Example 1
Using a three-type, three-layer, multi-manifold type T-die extruder, the film is formed in the order of non-foamed resin layer A / non-foamed resin layer / non-foamed resin layer B so that the thickness of each layer is 8 μm / 75 μm / 8 μm. Thus, a laminate A composed of three layers was obtained. The following resin compositions were used for the foamed resin layer and the non-foamed resin layers A and B, respectively. Here, the extrusion conditions are as follows: the cylinder temperature storing the resin composition for non-foamed resin layer A, the resin composition for foamed resin composition, and the resin composition for non-foamed resin layer B is 140 ° C., 120 ° C., and The temperature was 120 ° C.
(Resin composition for foamed resin layer)
・ Ethylene-vinyl acetate copolymer (“Evaflex V406 (trade name)”, manufactured by Mitsui DuPont Polychemical, vinyl acetate content: 20 wt%, MFR: 20 g / 10 min): 100 parts by mass Azodicarbonamide-based foaming agent, “Uniform Ultra AZ3050I (trade name)”, manufactured by Otsuka Chemical Co., Ltd.): 5 parts by mass • Foaming aid (“OF-101 (trade name)”, manufactured by ADEKA Corporation): 5 masses Part ・ Pigment (titanium oxide, “Tai Pure R103 (trade name)”, manufactured by DuPont): 20 parts by mass ・ Flow modifier (“P-100 (trade name)”, manufactured by Arakawa Chemical Co., Ltd.): 10 parts by weight (Resin composition for non-foamed resin layer A)
-Ethylene-vinyl acetate copolymer ("Evaflex EV150 (trade name)", manufactured by Mitsui DuPont Polychemicals, vinyl acetate content: 33% by weight): 100 parts by mass (resin composition for non-foamed resin layer B)
・ Ethylene-methacrylic acid copolymer (“Nucrel N1560 (trade name)”, methacrylic acid content: 15% by mass, MFR: 60 g / 10 min.

Thermal lamination of the non-foamed resin layer A surface of the laminate A and a backing paper (“WK-665 (trade name)” manufactured by Kojin Co., Ltd., weighing 65 g / m ² ) as a base material heated at 90 ° C. Then, a laminate B of base material / non-foamed resin layer A / unfoamed resin layer / non-foamed resin layer B is obtained, and the laminate B is irradiated with an electron beam (200 kV, 30 kGy) to perform a crosslinking treatment. went.
Next, on the non-foamed resin layer B of the laminate B, the following resin composition is applied by gravure printing to form a light diffusion reflection layer (thickness: 3 μm), and further an acrylic resin composition (one-part curing) A surface protection layer (thickness: 1 μm) was formed by applying a mold, “AL-TOP402B (trade name)” manufactured by Dainichi Seika Co., Ltd. Then, in a heating and foaming furnace at 230 ° C., the unfoamed resin layer is foamed to form a foamed resin layer, embossed from the surface protective layer side, and a texture pattern is formed. Obtained foam wallpaper. Table 1 shows the results of the above evaluation for the obtained foamed wallpaper.
(Resin composition for light diffuse reflection layer)
・ Curable resin: Polyester-acrylic copolymer: Mixture of 20 parts by mass and urethane resin: 5 parts by mass. Light diffusing agent (“R-931 (trade name)”, manufactured by DuPont, alumina / silica surface-treated. Titanium dioxide, average particle size: 0.55 μm, titanium oxide quality: 80%): 100 parts by mass (P / V ratio: 4)

Examples 2-7
In Example 1, a foamed wallpaper was obtained in the same manner as in Example 1 except that the thickness of the light diffusive reflection layer, the light diffusing agent, and the P / V ratio were changed to those shown in Table 1. Table 1 shows the results of the above evaluation for the obtained foamed wallpaper.

Example 8
In Example 1, a foamed wallpaper was obtained in the same manner as in Example 1 except that embossing was not performed. Table 1 shows the results of the above evaluation for the obtained foamed wallpaper.

Comparative Examples 1-3
In Example 1, a foamed wallpaper was obtained in the same manner as in Example 1 except that the thickness of the light diffusion reflection layer, the light diffusion agent, and the P / V ratio were changed to those shown in Table 2. Table 2 shows the results of the above evaluation on the obtained foamed wallpaper.

It is confirmed that the foamed wallpaper obtained in the examples has a high diffuse reflectance of 87% or more, excellent stain resistance, and excellent interlayer adhesion. It was. Furthermore, it was confirmed that the product was excellent in brightness (designability), had a calm design property without being too white to be calm.
On the other hand, the foamed wallpaper of Comparative Example 1 that does not have a light diffusive reflective layer does not have a white and calm design, and the foamed wallpaper of Comparative Example 2 that has a P / V ratio of 3 and a low titanium oxide content also has a color tone. However, the evaluation of brightness was inferior because it did not have a white and calm design. Further, the foamed wallpaper of Comparative Example 3 having a P / V ratio of 6 and a high titanium oxide content has a reflectance of 88.3%, but has poor adhesion and cannot be practically used as a foamed wallpaper. I have.

  According to the present invention, it is possible to obtain a foamed wallpaper having excellent performance of diffusing or reflecting light rays, that is, high diffuse reflectance. This foam wallpaper is suitably used as a building interior material such as a wall surface, ceiling, or door.

DESCRIPTION OF SYMBOLS 1 Foam wallpaper 2 Base material 3A, 3B Non-foamed resin layer 4 Foamed resin layer 5 Light diffuse reflection layer 6 Picture layer 7 Surface protective layer 8 Uneven pattern

Claims (12)

  2. A substrate, a foamed resin layer, and a light diffusing and reflecting layer are provided in this order, and the light diffusing and reflecting layer has a mass ratio (P / V) of the content P of the light diffusing agent and the content V of the curable resin. A foam wallpaper which is a cured product of a resin composition containing a light diffusing agent and a curable resin so as to be 5 to 5.5.   The foamed wallpaper according to claim 1, wherein the light diffusing agent is at least one selected from titanium oxide, barium sulfate, magnesium sulfate, silicon oxide, magnesium carbonate, calcium carbonate, and zinc oxide.   The foamed wallpaper according to claim 1, wherein the light diffusing agent is titanium oxide having a quality of 80 to 90%.   The foamed wallpaper according to claim 2 or 3, wherein the titanium oxide is surface-treated with silica and alumina.   The foamed wallpaper according to any one of claims 1 to 4, wherein the curable resin contains a polyester-acrylic copolymer and a urethane resin.   The foamed wallpaper according to claim 5, wherein the curable resin contains 1 to 50 parts by mass of a urethane resin with respect to 100 parts by mass of the polyester-acrylic copolymer.   The foamed wallpaper according to any one of claims 1 to 6, wherein the light diffuse reflection layer has a thickness of 3 to 15 µm.   The foamed wallpaper according to any one of claims 1 to 7, wherein the foamed resin layer contains an ethylene-vinyl acetate copolymer as a resin component.   The foamed wallpaper according to any one of claims 1 to 8, which has a non-foamed resin layer A between the substrate and the foamed resin layer.   The foamed wallpaper according to any one of claims 1 to 9, further comprising a non-foamed resin layer B between the foamed resin layer and the light diffusing and reflecting layer.   The foam wallpaper according to any one of claims 1 to 10, further comprising a surface protective layer on the light diffusion reflection layer.   The foamed wallpaper according to any one of claims 1 to 11, wherein the surface has an uneven pattern.