Laminate and method for manufacturing the same, as well as wallpaper and decorative sheets.

Abstract

To provide a laminate that exhibits water-repellent properties efficiently. [Solution] A laminate comprising a base layer, a foamed resin layer, and a water-repellent layer laminated in this order, wherein the surface of the foamed resin layer has a contact angle of 20° or more, and the surface of the foamed resin layer is partially covered by the water-repellent layer.

Description

[Technical Field]

[0001] This invention relates to laminates and methods for manufacturing them, as well as to wallpaper and decorative sheets. [Background technology]

[0002] The properties required of laminates vary widely depending on their application and location of use. For example, when laminates are used as wallpaper or decorative sheets in houses or offices, they require not only aesthetic appeal but also strength and water repellency. To meet these requirements, techniques such as embossing or applying a coating layer to the surface of the wallpaper or decorative sheet are employed.

[0003] For example, Patent Document 1 discloses wallpaper having a surface protection layer on the surface side of a polyvinyl chloride resin layer. Patent Document 2 also discloses wallpaper in which portions of a foamed resin layer are dispersed on the surface of a surface functional layer made of a matting agent. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2014-109087 [Patent Document 2] Japanese Patent Publication No. 2020-190041 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] However, laminates with a water-repellent layer covering the entire surface had a problem where the design quality deteriorated due to punctures occurring when the laminate was further heated (hereinafter also referred to as "reheating") and embossed after its formation. In addition, when the water-repellent layer was formed on only a part of the surface of the laminate, there was a problem in that the water-repellent performance did not manifest efficiently.

[0006] In view of the above circumstances, an object of the present invention is to provide a laminate that exhibits excellent water repellency efficiently. **Means for Solving the Problems**

[0007] As a result of intensive studies, the present inventors have found that the above problems can be solved by setting the contact angle of the surface of the foamed resin layer within a predetermined range in a laminate having a specific layer structure, and have completed the present invention.

[0008] That is, the present invention relates to the following.

[0009] Aspect 1 of the present invention is a laminate in which a base material layer, a foamed resin layer, and a water repellent layer are laminated in this order, the surface of the foamed resin layer has a contact angle of 20° or more, and the surface of the foamed resin layer is partially covered by the water repellent layer.

[0010] Aspect 2 of the present invention is the laminate according to Aspect 1, where the ratio of the area covered by the water repellent layer to the area of the surface of the foamed resin layer is 50 to 90%.

[0011] Aspect 3 of the present invention is the laminate according to Aspect 1 or 2, where the water repellent agent contained in the water repellent layer is a non-fluorine-based water repellent agent.

[0012] Aspect 4 of the present invention is the laminate according to any one of Aspects 1 to 3, where the foamed resin layer contains a polyvinyl chloride-based resin.

[0013] Aspect 5 of the present invention is the laminate according to Aspect 4, where the content of the polyvinyl chloride-based resin based on the total mass of the foamed resin layer is 30 to 65% by mass.

[0014] Aspect 6 of the present invention is the laminate according to Aspect 4 or 5, The aforementioned foamed resin layer further contains a filler, The present invention relates to a laminate in which, when the polyvinyl chloride resin content in the foamed resin layer is 100 parts by mass, the content of the filler is greater than 0 parts by mass and 30 parts by mass or less.

[0015] Aspect 7 of the present invention is a laminate in any one of aspects 1 to 6, Regarding laminates for use in wallpaper.

[0016] Embodiment 8 of the present invention is a laminate in any one of embodiments 1 to 7, This relates to laminates for use in decorative sheets.

[0017] Aspect 9 of the present invention is A step of forming a foamed resin precursor layer using a foamed resin layer forming composition, The process involves applying a water-repellent layer-forming composition to the surface of the foamed resin precursor layer using a bias mesh roll, and The present invention relates to a method for manufacturing a laminate according to any one of embodiments 1 to 8, which includes, in this order, a step of foaming the aforementioned foamed resin precursor layer to form a foamed resin layer.

[0018] Aspect 10 of the present invention is The present invention relates to a wallpaper comprising one of the laminates described in embodiments 1 to 7, wherein the water-repellent layer side of the laminate is embossed.

[0019] Aspect 11 of the present invention is The present invention relates to a decorative sheet comprising one of the laminates from embodiments 1 to 6 and 8, wherein the water-repellent layer side of the laminate is embossed. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a laminate that efficiently exhibits water-repellent properties. [Brief explanation of the drawing]

[0021] [Figure 1] Figure 1 shows one aspect of the layer structure in a laminate according to an embodiment of the present invention. [Figure 2] Figure 2 shows one aspect of how the surface of the foamed resin layer is partially covered by a water-repellent layer. [Figure 3] Figure 3 shows one aspect of how the surface of the foamed resin layer is partially covered by a water-repellent layer. [Modes for carrying out the invention]

[0022] The laminate and its manufacturing method, as well as wallpaper or decorative sheets, of the present invention will be described below, but the present invention is not limited to these. Furthermore, in this specification, "A~B" indicating a numerical range means a range that includes A and B, and indicates "A or greater and B or less".

[0023] <Laminate> In an embodiment of the present invention, a laminate is formed by laminating a base layer, a foamed resin layer, and a water-repellent layer in this order, wherein the surface of the foamed resin layer has a contact angle of 20° or more, and the surface of the foamed resin layer is partially covered by the water-repellent layer. As one embodiment, as shown in Figure 1, a laminate 10 has a layer structure in which a foamed resin layer 2 is laminated on a base layer 1, and the surface of the foamed resin layer 2 is partially laminated with a water-repellent layer 3.

[0024] [Base material layer] In this embodiment, there are no particular limitations on the base material layer, and examples include materials used as base materials for wallpaper or decorative sheets. More specific examples include paper, fabric, nonwoven fabric, synthetic resin sheet, or composite materials thereof.

[0025] Examples of papers that can be used as the base layer include coated paper, kenaf paper, plain paper, recycled paper, Japanese paper, and fine paper. Furthermore, these papers may contain inorganic fillers (such as aluminum hydroxide) or flame retardants. Examples of fabrics that can be used as the base layer include knitted or woven fabrics made from natural fibers, synthetic fibers, semi-synthetic fibers, regenerated fibers, etc. Examples of synthetic resin sheets that can be used as the base layer include polyolefins, vinyl chloride resins, olefin-based thermoplastic elastomers, and ABS (acrylonitrile-butadiene-styrene) resins.

[0026] The base layer can be selected depending on the application of the laminate and the desired properties. For example, using paper as the base layer is preferable because it allows for inexpensive construction using starch adhesive. Also, using nonwoven fabric as the base layer is preferable because it makes it easy to peel off the substrate, and after peeling, it is possible to easily apply new wallpaper or decorative sheet.

[0027] There are no particular restrictions on the thickness of the base layer, but it is preferably 0.1 mm or more, more preferably 0.11 mm or more, and even more preferably 0.13 mm or more. Furthermore, it is preferably 0.2 mm or less, more preferably 0.16 mm or less, and even more preferably 0.15 mm or less. In particular, a base layer thickness of 0.11 mm or more is preferable because it improves the ability to conceal unevenness. Furthermore, a thickness of 0.15 mm or less is preferable because it improves fire resistance.

[0028] [Foamed resin layer] (Surface contact angle) In this embodiment, the surface of the foamed resin layer has a contact angle of 20° or more, preferably 25° or more, more preferably 30° or more, and even more preferably 35° or more. There is no particular upper limit to the contact angle of the surface of the foamed resin layer, but it can be, for example, 60° or less. The contact angle in this specification can be measured by a method in accordance with JIS R 3257:1999.

[0029] If the contact angle of the foamed resin layer surface is less than 20°, the water-repellent properties of the laminate may not be achieved. Furthermore, water repellency after reheating may be reduced. Here, reheating the laminate can be considered equivalent to heating when embossing wallpaper or decorative sheets. In other words, when a laminate in which the contact angle of the surface of the foamed resin layer is less than 20° is used for wallpaper or decorative sheets, the water repellency of the wallpaper or decorative sheet obtained after embossing or the like may be inferior.

[0030] The reason why this effect is obtained when the surface of the foamed resin layer has a contact angle of 20° or more is not clear, but since there are some parts where the foamed resin layer is exposed and not covered by the water-repellent layer, it is thought that the properties of the exposed foamed resin layer affect the water-repellent performance of the laminate.

[0031] The contact angle of the surface of the foamed resin layer can be adjusted as appropriate by changing the composition of the foamed resin layer. For example, when the foamed resin layer contains an emulsifier, lowering the emulsifier content relative to the total mass of the foamed resin layer can be adjusted to a higher contact angle on the surface of the foamed resin layer. The preferred emulsifier content in the foamed resin layer can be appropriately set depending on the type of emulsifier. Also, for example, increasing the content of fillers, etc., relative to the total mass of the foamed resin layer and lowering the content of polyvinyl chloride resin will result in a lower emulsifier content, thus allowing the contact angle of the surface of the foamed resin layer to be adjusted to a higher angle. In addition, for example, by lowering the content of hydrophilic additives based on the total mass of the foamed resin layer, the contact angle on the surface of the foamed resin layer can be adjusted to be higher.

[0032] (Polyvinyl chloride resin) The foamed resin layer preferably contains a polyvinyl chloride resin. Furthermore, the resin component contained in the foamed resin layer preferably consists of a polyvinyl chloride resin. The reasons for the preference for using polyvinyl chloride resin in the foamed resin layer are as follows: First, polyvinyl chloride resin is preferable because its viscosity can be appropriately adjusted using plasticizers, thus offering greater design flexibility for the foamed resin layer. Second, because polyvinyl chloride resin contains chlorine atoms, it has excellent flame retardancy, eliminating the need to add flame retardants to the foamed resin layer. Furthermore, because polyvinyl chloride resin has a molecular structure in which chlorine atoms are bonded to every other carbon atom in the carbon chain, it is resistant to ultraviolet light, resulting in high resistance to oxidation and aging of the foamed resin layer, which is preferable.

[0033] There are no particular restrictions on the polyvinyl chloride resin content based on the total mass of the foamed resin layer, but it is preferably 30% by mass or more, more preferably 35% by mass or more, even more preferably 50% by mass or more, and particularly preferably 55% by mass or more. Also, it is preferably 65% ​​by mass or less, and more preferably 60% by mass or less. In one embodiment, the polyvinyl chloride resin content based on the total mass of the foamed resin layer can be 30 to 65% by mass. A content of 30% by mass or more is preferable because it increases the strength of the laminate. For example, when the laminate is used for wallpaper or decorative sheets, it is preferable because it can maintain good strength in the wallpaper or decorative sheet after embossing. Furthermore, it is preferable that the above content is 65% by mass or less, as this makes it less likely for air bubbles to remain in the foamed resin layer. For example, when the laminate is used for wallpaper or decorative sheets, it is preferable because it can prevent punctures during embossing caused by air bubbles in the foamed resin layer.

[0034] There are no particular restrictions on the average degree of polymerization of the polyvinyl chloride resin contained in the foamed resin layer, but it is preferably 750 or higher, more preferably 950 or higher, and even more preferably 1,000 or higher. Furthermore, it is preferably 1,600 or lower, more preferably 1,400 or lower, and even more preferably 1,200 or lower. A higher average degree of polymerization is preferable because it improves the surface strength of the laminate and the overall durability of the laminate. For example, when the laminate is used for wallpaper or decorative sheets, it is preferable because it improves the surface strength of the wallpaper or decorative sheet and the overall durability of the wallpaper or decorative sheet while maintaining the reproducibility of the embossing. Furthermore, it is preferable that the average degree of polymerization is 1,600 or less, as this improves the processability of the laminate. For example, when the laminate is used for wallpaper or decorative sheets, it is preferable because it improves the reproducibility of the embossing.

[0035] (Filler) The foamed resin layer preferably contains a filler. The reasons why it is preferable to use a filler in the foamed resin layer are as follows. First, it is preferable that the composition for forming the foamed resin layer (hereinafter also referred to as the "foamed resin layer forming composition") contains a filler, as it makes it easier to coat the substrate. Second, it is preferable that the foamed resin layer forming composition contains a filler, as it reduces the manufacturing cost of the laminate. Furthermore, it is preferable that, for example, when the laminate is used for wallpaper or decorative sheets, the reproducibility of the embossing is improved.

[0036] There are no particular restrictions on the fillers that can be included in the foamed resin layer, but examples include calcium carbonate, magnesium carbonate, magnesium silicate, aluminum hydroxide, talc, silica, and diatomaceous earth. These fillers may be used individually or in combination of two or more types. Of these fillers, calcium carbonate and aluminum hydroxide are preferred. When these preferred fillers are included in a foamed resin layer-forming composition, the composition exhibits excellent sol stability and is easier to coat onto a substrate, which is advantageous. Furthermore, when the laminate is used for applications such as wallpaper or decorative sheets, it is advantageous in that it improves the reproducibility of embossing. In addition, calcium carbonate is advantageous in terms of cost and improved flame retardancy, while aluminum hydroxide is particularly advantageous in terms of flame retardancy.

[0037] There are no particular restrictions on the content of fillers in the foamed resin layer, but for example, when the content of polyvinyl chloride resin is 100 parts by mass, the content of fillers is preferably more than 0 parts by mass, more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more. Furthermore, it is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, and even more preferably 20 parts by mass or less. When the above content is greater than 0 parts by mass, it is preferable because it improves the surface strength of the foamed resin layer. Furthermore, for example, when the laminate is used for wallpaper or decorative sheet applications, it is preferable in that it has excellent conformability to the substrate material (such as gypsum board). Furthermore, it is preferable that the above content is 30 parts by mass or less, as this results in excellent manufacturing costs and makes it easier to coat the foamed resin layer-forming composition onto the substrate. Moreover, it is preferable, for example, when the laminate is used for wallpaper or decorative sheet applications, as this improves the reproducibility of the embossing.

[0038] In cases where the foamed resin layer contains a polyvinyl chloride resin, the laminate according to the embodiment of the present invention can be, for example, a laminate in which the foamed resin layer further contains a filler, and the content of the filler is greater than 0 parts by mass and 30 parts by mass or less, when the content of the polyvinyl chloride resin in the foamed resin layer is 100 parts by mass.

[0039] (Other agents) The foamed resin layer may contain other agents in addition to the polyvinyl chloride resin and fillers. There are no particular limitations on the other agents that the foamed resin layer may contain, but examples include anionic emulsifiers such as alkylbenzene sulfonates, nonionic emulsifiers such as fatty acid esters; stabilizers such as metal halides, barium compounds, calcium compounds, tin compounds, zinc compounds, and potassium compounds; foaming agents such as azo compounds; colorants; processing aids; antibacterial agents; antifungal agents; flame retardants; defoaming agents; and viscosity reducers.

[0040] (Properties of the foamed resin layer) There are no particular restrictions on the thickness of the foamed resin layer, but it is preferably 0.2 mm or more, more preferably 0.3 mm or more, and even more preferably 0.4 mm or more. Furthermore, it is preferably 0.9 mm or less, more preferably 0.8 mm or less, and even more preferably 0.7 mm or less.

[0041] [Water-repellent layer] In this embodiment, the surface of the foamed resin layer described above is partially covered with a water-repellent layer.

[0042] (Composition of the water-repellent layer) Water-repellent layers typically contain water-repellent agents. These agents can be broadly classified into two types: fluorine-based and non-fluorine-based water-repellent agents. Examples of non-fluorine-based water-repellent agents include silicone-based, polyurethane-based, and polyacrylic-based water-repellent agents. From the perspective of minimizing environmental impact, in this embodiment, it is preferable that the water-repellent agent included in the water-repellent layer is a non-fluorine-based water-repellent agent. Fluorine-based water-repellent agents take a long time to decompose, raising concerns about their potential to contribute to air pollution, soil pollution, and water pollution.

[0043] The water-repellent layer is usually formed by coating or printing an emulsion containing a water-repellent agent. There are no particular restrictions on the water-repellent agent content relative to the total mass of the emulsion used to form the water-repellent layer, but it is preferably 0.01% by mass or more, more preferably 0.05% by mass or more. Furthermore, it is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 2% by mass or less.

[0044] The water-repellent layer may contain other agents in addition to the water-repellent agent. There are no particular restrictions on the other agents that the water-repellent layer may contain, but examples include antibacterial agents.

[0045] (Percentage of area) The ratio of the area covered by the water-repellent layer to the surface area of the foamed resin layer is preferably 50% or more, more preferably 60% or more, and still more preferably 70% or more. Also, it is preferably 90% or less, and more preferably 80% or less. As one aspect, the ratio of the area covered by the water-repellent layer to the surface area of the foamed resin layer can be 50 to 90%. When the above ratio is 50% or more, it is preferable because water repellency is likely to be exhibited. Also, when it is 90% or less, the gas escape property generated by the decomposition of the foaming agent is improved, no puncture occurs during embossing, and the design property of the foamed resin layer is excellent, so it is preferable.

[0046] In this specification, the ratio of the area covered by the water-repellent layer to the surface area of the foamed resin layer can be determined from the shape of the plate for printing the composition for forming the water-repellent layer, which is the material of the water-repellent layer. More specifically, it can be determined from the specifications of the plate for printing the composition for forming the water-repellent layer, that is, the volume value which is the printing volume per unit area and the depth and shape of the recesses of the plate.

[0047] For example, when printing the composition for forming the water-repellent layer with a bias mesh roll described later, the composition for forming the water-repellent layer is printed in accordance with the shape of the recesses of the plate, and the shape of the recesses of the plate varies depending on the engraving method of the bias mesh roll (for example, conical shape or cylindrical shape). Therefore, the ratio (unit: %) of the area covered by the water-repellent layer to the surface area of the foamed resin layer is determined by the following order from the volume value (unit: cm 3 / m 2 ) and the depth (unit: μm). (1) Derivation of the formula (A) for the printing area (m 2 ) per 1 m 2 When the shape of the recesses of the plate is conical, the following relationship holds between the printing area per 1 m 2 3 and the volume value and the depth. [Volume value (cm 2 / m 2 )] / 1,000,000×3 =[Printing area per 1 m 2 (m 3 0>)]×[depth (μm)] / 1,000,000 From this equation, equation (A) below can be derived. [1m 2 Printing area per square meter (m²) 2 )] =[Volume value (cm 3 / m 2 )]×3÷[depth (μm)] ··· (A) (2) Calculation of the ratio (area ratio) (%) of the surface area covered by the water-repellent layer to the surface area of ​​the foamed resin layer. From equation (A) above, "1m 2 Printing area per square meter (m²) 2 Calculate the value of ")" and substitute it into the following formula (B) to calculate the "area ratio (%)". [Area ratio (%)] =[1m 2 Printing area per square meter (m²) 2 )÷1(m 2 ) × 100 ··· (B)

[0048] The shape and area of ​​the portion where the water-repellent layer is formed depends on the type of printing plate used. For example, when forming a water-repellent layer using gravure printing, the recesses in the plate correspond to the portion where the water-repellent layer is formed, and the shape and area of ​​these recesses determine the area and shape of the water-repellent layer. In other words, even when printing the water-repellent layer formation composition using a method other than a bias mesh roll, 1m 2 The relationship between the printing area, volume, and depth can be easily determined from the shape of the recesses in the printing plate. Therefore, the area ratio can be determined according to the specifications of the printing plate using a method similar to the calculation method described above.

[0049] As long as the ratio of the area covered by the water-repellent layer to the surface area of ​​the foamed resin layer is within the range described above, there are no particular restrictions on the shape of the formed water-repellent layer or the shape of the parts where the water-repellent layer is not formed. Examples of such shapes include stripes; grids; spots; circular shapes; elliptical shapes; rectangular shapes or other island-like shapes; and random shapes. Since a water-repellent layer is easily applied uniformly to the surface of the foamed resin layer, among these shapes, stripe, grid, and island shapes are preferred, and circular, elliptical, and rectangular shapes are more preferred. The arrangement of the shapes may be aligned, staggered, or random.

[0050] Figures 2 and 3 are schematic diagrams showing how a water-repellent layer is formed on the surface of a foamed resin layer. In these figures, rectangular or circular areas correspond to areas where the water-repellent layer is not formed. Furthermore, these figures are intended to schematically show the shape of the areas where the water-repellent layer is not formed, and do not accurately represent the ratio of the area covered by the water-repellent layer to the surface area of ​​the foamed resin layer.

[0051] (Properties of the water-repellent layer) There are no particular restrictions on the thickness of the water-repellent layer, but it is preferably 2.0 μm or more, and more preferably 3 μm or more. Furthermore, it is preferably 10 μm or less, and more preferably 5 μm or less.

[0052] [Other layers] The laminate according to the embodiment of the present invention may include other layers in addition to the base layer, foamed resin layer, and water-repellent layer. Examples of other layers include a pattern layer and an anchor coat layer. Other layers may be provided between the foamed resin layer and the water-repellent layer, as long as they do not interfere with the effects of the present invention.

[0053] [Applications of laminates] There are no particular limitations on the use of the laminate according to the embodiment of the present invention, but examples include wallpaper, decorative sheets, baseboards, etc. In one embodiment, the laminate according to the embodiment of the present invention is a laminate for use in wallpaper. In another embodiment, the laminate according to the embodiment of the present invention is a laminate for use in decorative sheets. The following description of a laminate according to an embodiment of the present invention will use a laminate for use in wallpaper or decorative sheets as an example, but there are no particular restrictions on its use.

[0054] When using a laminate according to an embodiment of the present invention in wallpaper, one example is a wallpaper that includes the above-mentioned laminate, wherein the water-repellent layer side of the laminate is embossed. Furthermore, when using a laminate according to an embodiment of the present invention as a decorative sheet, one possible embodiment is a decorative sheet that includes the above-mentioned laminate, wherein the water-repellent layer side of the laminate is embossed. The laminate according to the embodiment of the present invention has a water-repellent layer formed on its surface in a manner that prevents punctures during embossing. Therefore, it can be suitably used as a laminate for obtaining wallpaper or decorative sheets with excellent design, especially when manufacturing embossed wallpaper or decorative sheets.

[0055] <Method for manufacturing laminates> There are no particular restrictions on the method for manufacturing the laminate, as long as the laminate according to the embodiment of the present invention can be obtained. One embodiment of the method for manufacturing the laminate is shown below.

[0056] [Method for forming a foamed resin layer] The foamed resin layer can be formed, for example, by appropriately selecting a known method. As an example of such a method, a foamed resin layer-forming composition is laminated onto a substrate by a paste coating method or a calendering method to form a resin layer before foaming (hereinafter also referred to as the "foamed resin precursor layer"). Then, the foamed resin layer is obtained by foaming the foamed resin precursor layer by heating or other means.

[0057] In this embodiment, the following method can be used to form a foamed resin layer whose surface is partially covered with a water-repellent layer. That is, a foamed resin precursor layer is formed by the method described above, and then a water-repellent layer is formed on the obtained foamed resin precursor layer by the method described later. Subsequently, the foamed resin precursor layer on which the water-repellent layer has been formed can be heated or otherwise foamed to form the desired foamed resin layer.

[0058] [Method for forming a water-repellent layer] A water-repellent layer can be formed, for example, by appropriately selecting a known method. An example of such a method is applying a water-repellent layer-forming composition using gravure printing. Furthermore, a gravure printing method using a bias mesh roll can be employed to form the water-repellent layer-forming composition. Here, a bias mesh roll is a roll having multiple protrusions formed on its surface corresponding to the portion where the foamed resin layer is exposed. The formation of the layer using a bias mesh roll can be carried out, for example, in accordance with the method described in Japanese Patent Application Publication No. 2020-190041.

[0059] From the viewpoint of preventing punctures in wallpaper or decorative sheets, a method of applying a water-repellent layer-forming composition using a bias mesh roll is preferred as a method for forming a water-repellent layer. In the manufacture of wallpaper or decorative sheets having a water-repellent layer, punctures may occur during embossing due to the formation of bubbles caused by gas generated when forming the foamed resin layer. However, when a bias mesh roll is used, areas where gas can escape (areas where the water-repellent layer-forming composition is not applied by the bias mesh roll) are created on the surface of the foamed resin layer, thus preventing punctures. In other words, the method for manufacturing a laminate according to the embodiment of the present invention preferably includes a step of applying a water-repellent layer-forming composition to the surface of a foamed resin precursor layer using a bias mesh roll.

[0060] [Other methods for forming layers] In addition to the methods for forming each of the above layers, a laminate including other layers can be obtained by appropriately adding methods for forming other layers as needed. The methods for forming the other layers can be appropriately selected from known methods.

[0061] [Method for manufacturing laminates] A laminate according to an embodiment of the present invention can be manufactured by combining the methods for forming each of the layers described above. In one embodiment, the laminate can be manufactured by a method that includes, in this order, the steps of: forming a foamed resin precursor layer with a foamed resin layer forming composition; applying a water-repellent layer forming composition to the surface of the foamed resin precursor layer with a bias mesh roll; and foaming the foamed resin precursor layer to form a foamed resin layer. [Examples]

[0062] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0063] <Example 1> [Formation of a foamed resin precursor layer with a substrate] Composition A for forming a foamed resin layer was obtained by kneading 100 parts by mass of polyvinyl chloride resin A, 47 parts by mass of DOP (bis(2-ethylhexyl) phthalate, plasticizer), 15 parts by mass of calcium carbonate, 2.5 parts by mass of Ba-Zn compound (custom-made, stabilizer), 3.0 parts by mass of ADCA (azodicarbonamide, foaming agent), and 9.0 parts by mass of titanium dioxide using a dissolver-type kneader (manufactured by Primix Corporation). Using a coater, composition A for forming a foamed resin layer was applied onto the backing paper of the substrate, and after a drying process, a foamed resin precursor layer A with the substrate was obtained.

[0064] [Formation of a water-repellent layer] Using a gravure printing method with a bias mesh roll having a circular convex surface formed on its surface, a water-repellent agent (vinyl chloride emulsion, trade name "Vinibran (custom-made)", manufactured by Nisshin Chemical Industry Co., Ltd.) was printed onto the main surface of the foamed resin precursor layer A on the substrate side, and a water-repellent layer A was formed by going through a drying process.

[0065] [Formation of laminates] A foamed resin precursor layer A with a substrate on which a water-repellent layer A has been formed was heated at 255°C for 25 seconds (product name "Gear Oven", manufactured by Toyo Seiki Seisakusho Co., Ltd.) to foam the foamed resin precursor layer and form a foamed resin layer, thereby obtaining a laminate A. Measurements using a dial gauge revealed that the thickness of the foamed resin layer in laminate A was 0.745 mm, and the thickness of the water-repellent layer A was 3 μm. Furthermore, the water-repellent layer A was formed such that the areas where it was not present had a circular shape.

[0066] [Evaluation of laminates] The laminate and foamed resin layer were evaluated as follows.

[0067] (Contact angle before reheating) The contact angles of each surface described below were measured according to the method in accordance with JIS R 3257:1999 and were recorded as the contact angles before reheating. The results are shown in Table 1. • Contact angle of the laminate surface: This refers to the contact angle of the laminate surface obtained by heating and foaming a foamed resin precursor layer that has a water-repellent layer formed on it. • Contact angle of the foamed resin layer surface: This refers to the contact angle of the foamed resin layer surface obtained by heating and foaming the foamed resin precursor layer A without forming a water-repellent layer.

[0068] (Contact angle of the laminate after reheating) Using a heating test machine (product name "Gear Oven," manufactured by Toyo Seiki Seisakusho Co., Ltd.), the laminate was reheated at 190°C for 60 seconds, 200°C for 30 seconds, or 210°C for 30 seconds. After returning to room temperature, the contact angle of the laminate surface was measured according to the method in accordance with JIS R 3257:1999, and this was defined as the contact angle of the laminate after reheating. The results are shown in Table 1.

[0069] (The ratio of the area covered by the water-repellent layer to the surface area of ​​the foamed resin layer) The ratio of the area covered by the water-repellent layer to the surface area of ​​the foamed resin layer is the volume value (unit: cm) specified below for the bias mesh roll (shape of the recess in the plate: conical). 3 / m 2The area ratio (in μm) was calculated from the surface area and depth (in μm). Specifically, the area ratio (in %) was determined from the above-mentioned formulas (A) and (B), and this was taken as the ratio of the area covered by the water-repellent layer to the surface area of ​​the foamed resin layer. [1m 2 Printing area per square meter (m²) 2 )] =[Volume value (cm 3 / m 2 )]×3÷[depth (μm)] ··· (A) [Area ratio (%)] =[1m 2 Printing area per square meter (m²) 2 )÷1(m 2 ) × 100 ··· (B)

[0070] The volume and depth obtained from the specifications of the bias mesh roll used in Example 1 were as follows. Volume: 9.0 cm³ 2 / m 3 Depth: 35μm Substituting these values ​​into equations (A) and (B) above, the area ratio was found to be 77%. In other words, the ratio of the area covered by the water-repellent layer to the surface area of ​​the foamed resin layer in laminate A was 77%.

[0071] <Example 2> A foamed resin precursor layer B with a substrate and a laminate B were obtained by the same method as in Example 1, except that polyvinyl chloride resin B was used instead of polyvinyl chloride resin A. The obtained laminate and foamed resin layer were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0072] <Example 3> A foamed resin precursor layer C with a substrate and a laminate C were obtained by the same method as in Example 1, except that polyvinyl chloride resin C was used instead of polyvinyl chloride resin A. The obtained laminate and foamed resin layer were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0073] <Example 4> A foamed resin precursor layer D with a substrate and a laminate D were obtained by the same method as in Example 1, except that polyvinyl chloride resin D was used instead of polyvinyl chloride resin A. The obtained laminate and foamed resin layer were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0074] <Comparative Example 1> A foamed resin precursor layer E with a substrate and a laminate E were obtained by the same method as in Example 1, except that polyvinyl chloride resin E was used instead of polyvinyl chloride resin A. The obtained laminate and foamed resin layer were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0075] <Comparative Example 2> A foamed resin precursor layer F with a substrate and a laminate F were obtained by the same method as in Example 1, except that polyvinyl chloride resin F was used instead of polyvinyl chloride resin A. The obtained laminate and foamed resin layer were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0076] Details of the materials used in the above examples and comparative examples are as follows. • Polyvinyl chloride resin A: Custom-made product (contains polyvinyl chloride resin (average degree of polymerization: 820) and emulsifier) • Polyvinyl chloride resin B: Custom-made product (contains polyvinyl chloride resin (average degree of polymerization: 950) and emulsifier) • Polyvinyl chloride resin C: Custom-made product (contains polyvinyl chloride resin (average degree of polymerization: 950) and emulsifier) • Polyvinyl chloride resin D: Custom-made product (contains polyvinyl chloride resin (average degree of polymerization: 900) and emulsifier) • Polyvinyl chloride resin E: Product name "LB-133", manufactured by Tosoh Corporation (contains polyvinyl chloride resin (average degree of polymerization: 900) and emulsifier) • Polyvinyl chloride resin F: Product name "PR-W", manufactured by Formosa (contains polyvinyl chloride resin (average degree of polymerization: 869) and emulsifier)

[0077] [Table 1]

[0078] From the results above, it was found that in Examples 1 to 4, the contact angle of the surface of the foamed resin layer was large (high water repellency), and furthermore, the contact angle of the water-repellent layer side of the laminate formed using this was also large (high water repellency). In addition, the decrease in the contact angle of the water-repellent layer side of the laminate in Examples 1 to 4 was suppressed even after reheating, indicating that the water repellency of the laminate is maintained even by heat. In contrast, in Comparative Examples 1 and 2, the contact angle of the surface on the foamed resin layer side of the intermediate laminate was small (low water repellency), and furthermore, the contact angle of the surface on the water-repellent layer side of the laminate formed using this was also small (low water repellency). [Industrial applicability]

[0079] The laminate of the present invention can be used, for example, in wallpaper, decorative sheets, baseboards, and the like. [Explanation of symbols]

[0080] 1 Base material layer 2. Foamed resin layer 3. Water-repellent layer 10 Laminate

Claims

1. The substrate layer, the foamed resin layer, and the water-repellent layer are laminated in this order. The surface of the foamed resin layer has a contact angle of 20° or more. A laminate in which the surface of the foamed resin layer is partially covered by the water-repellent layer.

2. The laminate according to claim 1, wherein the ratio of the area covered by the water-repellent layer to the surface area of ​​the foamed resin layer is 50 to 90%.

3. The laminate according to claim 1, wherein the water-repellent agent contained in the water-repellent layer is a non-fluorine-based water-repellent agent.

4. The laminate according to claim 1, wherein the foamed resin layer contains a polyvinyl chloride resin.

5. The laminate according to claim 4, wherein the content of the polyvinyl chloride resin, based on the total mass of the foamed resin layer, is 30 to 65% by mass.

6. The aforementioned foamed resin layer further contains a filler, The laminate according to claim 5, wherein the content of the filler is greater than 0 parts by mass and less than or equal to 30 parts by mass when the content of the polyvinyl chloride resin in the foamed resin layer is 100 parts by mass.

7. A laminate according to claim 1 for use as wallpaper.

8. A laminate according to claim 1 for use in decorative sheets.

9. A step of forming a foamed resin precursor layer using a foamed resin layer forming composition, The process involves applying a water-repellent layer-forming composition to the surface of the foamed resin precursor layer using a bias mesh roll, and A method for manufacturing a laminate according to any one of claims 1 to 8, comprising the step of foaming the foamed resin precursor layer to form a foamed resin layer in this order.

10. Wallpaper comprising a laminate according to any one of claims 1 to 7, wherein the water-repellent side of the laminate is embossed.

11. A decorative sheet comprising a laminate according to any one of claims 1 to 6 and 8, wherein the water-repellent layer side of the laminate is embossed.

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