Laminated structure

Abstract

To provide a laminated structure having a base material, a thermally foamed layer and a decorative layer, excellent in design effect, delaying the falling-off of a carbonized heat insulating layer and the decorative layer when exposed to high temperature by a fire or the like, delaying the temperature rise of the base material and obtaining stable heat resistant protective properties.SOLUTION: The laminated structure has a base material, a thermally foamed layer and a decorative layer on the surface side thereof, and has a specific recessed part on the rear surface of the decorative layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a novel laminate structure. [Background technology]

[0002] When structures such as buildings and civil engineering structures are exposed to high temperatures due to a fire or the like, there is a problem that the physical strength of base materials such as columns and beams is rapidly reduced. To address this problem, a laminated structure is known in which the base material is coated with a coating material having heat-resistant protective properties, thereby delaying the temperature rise during a fire and suppressing the reduction in the physical strength of the base material.

[0003] As an example of such a laminated structure, Patent Document 1 describes a fire-resistant structure including a base material, a heat-foamed layer, and a decorative material provided on the outside of the heat-foamed layer, and the decorative material is provided on the surface side to impart aesthetic appeal. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-161653 Summary of the Invention [Problem to be solved by the invention]

[0005] In the structure of Patent Document 1, the decorative material enhances the design, and when exposed to high temperatures due to a fire or the like, the temperature rise can be delayed by the carbonized insulating layer formed by the foaming of the heat-foamed layer. However, in a structure in which a heat-foamable layer and a decorative material are simply laminated, there is a risk that the decorative material will immediately fall off due to the temperature rise in the event of a fire. [Means for solving the problem]

[0006] As a result of intensive research into achieving the above-mentioned objective, the inventor came up with the idea that by providing a specific recess on the back surface of the decorative layer, it is possible to prevent the decorative layer from falling off due to temperature rise during a fire, and thus completed the present invention.

[0007] That is, the present invention has the following features. 1. A laminated structure having a thermal foaming layer on the surface side of a substrate and a decorative layer on the surface side of the thermal foaming layer, The back surface of the decorative layer has a recessed portion, The depth of the recess is 1 mm or more and 10 mm or less. 2. The laminated structure according to 1., wherein the proportion of the recesses on the rear surface of the decorative layer is 1% to 30% of the entire rear surface of the decorative layer. 3. The laminated structure according to 1., wherein the thickness of the decorative layer is 3 mm or more and 50 mm or less, and the depth of the recess on the back surface of the decorative layer is 5% or more and 45% or less of the thickness. [Effects of the Invention]

[0008] The laminated structure of the present invention has excellent designability and can prevent the decorative layer from falling off when exposed to high temperatures such as during a fire. [Brief explanation of the drawings]

[0009] [Figure 1] 1(a) is a cross-sectional view showing an example of the laminate structure of the present invention, and FIG. 1(b) is a view showing an example of the back surface of the decorative layer of the present invention. [Figure 2] 1 is a view showing an example of the back surface of the decorative layer of the present invention. [Figure 3] 1 is a view showing an example of the back surface of the decorative layer of the present invention. [Figure 4] 1 is a view showing an example of the back surface of the decorative layer of the present invention. [Figure 5] 1 is a diagram showing an example of the rear surface of a decorative layer as a comparative example of the present invention. [Explanation of symbols]

[0010] 1: Base material 2: Thermal foam layer 3: Decorative layer 3x: Cosmetic layer back recess DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention will be described.

[0012] Fig. 1 is a cross-sectional view showing an example of the laminate structure of the present invention. The laminate structure of the present invention has heat-resistant protection properties and design properties, and as shown in Fig. 1, is a laminate structure having a thermally foamed layer 2 on the surface side of a substrate 1, and a decorative layer 3 on the surface thereof.

[0013] (base material) Examples of the substrate 1 of the present invention include H-shaped steel beams, I-shaped steel beams, square columns, round columns, and surface materials formed from materials such as metal, wood, and concrete. Such substrates 1 are generally parts of structures such as buildings and civil engineering structures that should be fire-resistant, and include, for example, walls, columns, floors, beams, roofs, and stairs. In particular, the present invention is suitable for application to walls, columns, floors, beams, and the like that require design. In recent years, wood substrates have come to be used as an alternative to concrete substrates and steel frame substrates, and the present invention is also effective for wood substrates.

[0014] (Thermal foam layer) The thermally foamable layer 2 of the present invention foams when the ambient temperature rises due to a fire or the like and the temperature of the layer reaches a predetermined foaming temperature (preferably 180°C or higher, more preferably 200 to 400°C), and forms a carbonized insulating layer in that temperature range.

[0015] The thermally foamable layer 2 can be formed, for example, from a thermally foamable coating material or a thermally foamable sheet, and these can be used by laminating one or more types thereof.

[0016] The thermal foam layer 2 is preferably formed from a mixed composition containing a resin component, a flame retardant, a foaming agent, a carbonizing agent, and a filler as constituent components. In the event of a fire, these components work together to expand the layer, form a carbonized heat insulating layer, generate non-flammable gas, and perform other functions, thereby providing excellent heat insulation and heat-resistant protection.

[0017] Examples of resin components that can be used include thermoplastic resins such as vinyl resin, polystyrene resin, polypropylene resin, acrylic resin, acrylic-styrene resin, polyamide resin, polyurethane resin, vinyl acetate resin, and ethylene-vinyl acetate resin. Also usable are rubber materials such as natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, chloroprene rubber, nitrile rubber, butyl rubber, chlorinated butyl rubber, ethylene-propylene rubber, chlorosulfonated polyethylene, acrylic rubber, epichlorohydrin rubber, multi-vulcanized rubber, silicone rubber, fluororubber, and urethane rubber. These materials can be used alone or in combination. Among these, acrylic resin, acrylic-styrene resin, vinyl acetate resin, and ethylene-vinyl acetate resin are preferred.

[0018] Flame retardants generally exhibit at least one of the following effects in the event of a fire: dehydration and cooling, non-flammable gas generation, and promotion of carbonization of thermoplastic resins, thereby suppressing the combustion of resin components. The flame retardants used in the present invention are not particularly limited as long as they have such effects, and known flame retardants can be used. Examples include chlorine compounds, antimony compounds, phosphorus compounds, and boron compounds. These can be used alone or in combination of two or more. These can be used in either uncoated or coated products. Among these, phosphorus compounds such as ammonium phosphate and ammonium polyphosphate are preferably used.

[0019] The foaming agent generally has the effect of generating a non-flammable gas in the event of a fire, foaming the carbonizing resin component and carbonizing agent, and forming a carbonized insulating layer having pores. The foaming agent is not particularly limited as long as it has this effect, and known foaming agents can be used. Examples include melamine and its derivatives, dicyandiamide and its derivatives, azodicarbonamide, urea, and thiourea. These can be used alone or in combination of two or more. Among these, melamine, dicyandiamide, azodicarbonamide, etc. are preferably used.

[0020] Generally, a carbonizing agent has the effect of forming a thick carbonized insulating layer with excellent thermal insulation properties by dehydrating and carbonizing itself together with the carbonization of the thermoplastic resin during a fire. The carbonizing agent used in the present invention is not particularly limited as long as it has this effect, and known carbonizing agents can be used. Examples include polyhydric alcohols such as pentaerythritol, dipentaerythritol, and trimethylolpropane; starch, casein, etc. One carbonizing agent or a combination of two or more carbonizing agents can be used. Among these, pentaerythritol, dipentaerythritol, etc. are preferably used.

[0021] The filler generally has the effect of maintaining the strength of the carbonized heat insulating layer. There are no particular limitations on the filler as long as it has this effect, and known fillers can be used. Examples include carbonates such as calcium carbonate, sodium carbonate, magnesium carbonate, and aluminum oxide; metal oxides such as titanium dioxide and zinc oxide; and inorganic powders such as silica, clay, talc, kaolin, diatomaceous earth, shirasu, mica, wollastonite, silica sand, silica stone, quartz, vermiculite, alumina, and fly ash. These can be used alone or in combination. The shape of the filler is not particularly limited, and examples include spherical, granular, plate-like, rod-like, scale-like, and needle-like shapes.

[0022] In addition to the above-described components, various additives may be contained as needed in the thermally foamable layer 2. Any additives may be used as long as they do not significantly impair the effects of the present invention, and examples of such additives include pigments, fibers, wetting agents, plasticizers, lubricants, preservatives, antifungal agents, anti-algae agents, antibacterial agents, thickeners, dispersants, antifoaming agents, crosslinking agents, UV absorbers, light stabilizers, antioxidants, and dilution solvents.

[0023] The thermally foamable coating material used to form the thermally foamable layer 2 can be a liquid mixture containing the above-mentioned components and additives. The thermally foamable sheet used to form the thermally foamable layer can be a sheet-shaped mixture containing the above-mentioned components and additives.

[0024] The thermally foamed layer 2 may be composed solely of a mixture containing the above-mentioned components and additives, but from the standpoints of productivity, workability, flexibility, etc., it may also be composed of a reinforcing sheet such as a fibrous sheet laminated on the front or back surface or inside of the thermally foamed layer.

[0025] The thickness of the thermally foamable layer 2 may be appropriately set depending on the application site, etc., but is preferably 0.2 mm or more and 10 mm or less, and more preferably 0.3 mm or more and 6 mm or less. The thermally foamed layer 2 preferably has a uniform thickness and a flat surface. Such a thermally foamed layer 2 can improve adhesion and bonding to the flat surface other than the recesses on the back surface of the decorative layer 3, which will be described later.

[0026] (decorative layer) The decorative layer 3 of the present invention is provided on the surface side of the thermally foamed layer 2 and is not particularly limited as long as it can impart a design. Examples of woodblocks include wood such as cypress, cedar, Japanese hiba, domestic pine (Japanese pine, larch, Yezo spruce, Sakhalin fir, and spruce), Douglas fir, Norway spruce, and Norway sylvestris, and examples of woodblocks include lumber, plywood, laminated lumber, LVL (Laminated Veneer Lumber), CLT (Cross Laminated Timber), particle board, and fiberboard. Examples of sheet materials include sheet materials formed from mixed compositions containing resin components and colorants as constituent components. These surfaces may have a variety of appearances, such as transparent or opaque, colorless or colored, matte or glossy, monochromatic or multicolored, and smooth or uneven.

[0027] The back surface of the decorative layer 3 of the present invention has a recess, and the depth of the recess is 1 mm or more and 10 mm or less, preferably 1.2 mm or more and 8 mm or less. By providing such recesses, when the ambient temperature rises due to a fire or the like, the carbonized heat insulating layer formed by the foaming of the thermal foam layer 2 enters the recesses, and the anchoring effect of the carbonized heat insulating layer can prevent or delay the detachment of the decorative layer 3. Furthermore, the decorative layer 3 also has the effect of acting as a carbonized layer to delay the temperature rise of the substrate 1, thereby providing better heat-resistant protection.

[0028] The shape of the recesses in the decorative layer 3 of the present invention, as viewed from the back side, is not particularly limited and may be linear, spotted, lattice-like, or a combination thereof, and may be arranged regularly or randomly. When the shape is linear or lattice-like, the line width is not particularly limited as long as it is about 1 mm or more and 50 mm or less, and when it is spot-like, the maximum diameter of the size is about 1 mm or more and 50 mm or less. The cross-sectional shape of the recess is not particularly limited and may be a square, a triangle, a semicircle, or a combination thereof. In the present invention, the shape viewed from the back side may be, for example, as shown in Figure 1(b) and Figures 2 to 4, and in particular, recesses arranged linearly along a horizontal plane as shown in Figure 1(b) are preferred because they can better exert the anchoring effect of the carbonized insulation layer.

[0029] The proportion of the recesses (the area occupied by the recesses) on the back surface of the decorative layer 3 of the present invention is preferably 1% to 30%, more preferably 1.5% to 20%, and even more preferably 2% to 15% of the entire back surface of the decorative layer 3. This range is preferable because it provides excellent adhesion and adhesion to the thermally foamable layer 2 and excellent resistance to falling off. Other than the recesses on the rear surface of the decorative layer 3, the surface is flat with no irregularities, or a flat surface with the depth of the recesses of the irregularities being less than 1 mm.

[0030] The thickness of the decorative layer 3 of the present invention is preferably 3 mm or more and 50 mm or less, and more preferably 5 mm or more and 45 mm or less, and the depth of the recess on the back surface of the decorative layer 3 is preferably 5% or more and 45% or less, and more preferably 8% or more and 40% or less of the thickness.

[0031] The recesses on the rear surface of the decorative layer 3 are not particularly limited, but can be formed on the rear surface using, for example, a cutter, a drill, a saw, a carving knife, a chisel, or the like. When the above-mentioned sheet material is used as the decorative layer 3, a method of using a formwork or the like to form a recess on the back surface in advance when manufacturing the sheet material can also be used.

[0032] The resin component in the sheet material serves to fix the colorant. Various synthetic resins can be used as such a resin component. Examples of resins include acrylic resin, silicone resin, acrylic silicone resin, fluororesin, vinyl acetate resin, acrylic-vinyl acetate resin, vinyl chloride resin, urethane resin, acrylic urethane resin, epoxy resin, alkyd resin, polyvinyl alcohol resin, polyester resin, ethylene resin, polyvinyl alcohol, cellulose and its derivatives, and composites thereof. Such synthetic resins may have the property of undergoing a crosslinking reaction.

[0033] The colorant in the sheet material plays a role in imparting color, pattern, etc. to the decorative layer. As such a colorant, for example, known color pigments, extender pigments, aggregates, etc. can be used, and these can be used alone or in combination of two or more kinds. Examples of color pigments include inorganic chromatic pigments such as ferric oxide (red iron oxide), yellow iron oxide, ultramarine, and cobalt green; organic chromatic pigments such as azo, naphthol, pyrazolone, anthraquinone, perylene, quinacridone, disazo, isoindolinone, benzimidazole, phthalocyanine, and quinophthalone; black pigments such as carbon black, iron-manganese composite oxide, iron-copper-manganese composite oxide, iron-chromium-cobalt composite oxide, copper-chromium composite oxide, copper-manganese-chromium composite oxide, and black iron oxide; and white pigments such as titanium oxide, zinc oxide, and alumina. Examples of extender pigments include heavy calcium carbonate, light calcium carbonate, kaolin, clay, china clay, diatomaceous earth, hydrous finely powdered silicic acid, talc, barite powder, barium sulfate, precipitated barium sulfate, barium carbonate, magnesium carbonate, silica powder, and aluminum hydroxide. Examples of aggregates include marble, granite, serpentine, granite, sandstone, slate, basalt, gabbro, diorite, andesite, limestone, fluorite, gabbros, feldspar, silica, silica sand and crushed products thereof, crushed porcelain, crushed ceramics, crushed metal particles and crushed products thereof, crushed glass, glass beads, etc., or those with colored surfaces.

[0034] The sheet material may contain other components (additives) as needed, as long as they do not significantly impair the effects of the present invention, such as plasticizers, anti-algae agents, antibacterial agents, deodorizers, adsorbents, flame retardants, thickeners, antifoaming agents, crosslinking agents, fibers, UV absorbers, light stabilizers, antioxidants, catalysts, etc.

[0035] The sheet material may be composed only of a mixture containing the above-mentioned components and additives, but from the standpoint of productivity, workability, flexibility, etc., a reinforcing sheet such as a fibrous sheet may be laminated on the front or back surface of the sheet material, or inside the sheet material.

[0036] (Laminated structure) As shown in FIG. 1, the laminated structure of the present invention is a laminated structure having a thermally foamed layer 2 on the surface side of a substrate 1, and a decorative layer 3 on the surface side thereof. The method for producing the laminated structure of the present invention is not particularly limited, but it may be produced by a method in which a thermally foamed layer 2 is laminated on the surface side of the substrate 1, and then a decorative layer 3 is laminated on the surface side of that, or a method in which a thermally foamed layer 2 and a decorative layer 3 are laminated in advance and then laminated on the substrate 1, etc. The lamination can be carried out using known adhesives or fasteners such as nails, screws, rivets, pins, bolts, and staples.

[0037] In addition, it is preferable that the laminated structure of the present invention has a hollow portion originating from the recessed portion on the back surface of the decorative layer 3. In the event of a fire, etc., the carbonized insulating layer formed by the foaming of the thermal foam layer 2 enters the hollow portion, and the anchoring effect of the carbonized insulating layer prevents the decorative layer 3 from falling off, and the decorative layer 3 becomes a carbonized layer, which also has the effect of suppressing the temperature rise of the substrate 1. The surface of the thermally foamed layer 2 is preferably flat, and this can improve the adhesiveness and adhesion to the flat surface other than the recessed portions on the back surface of the decorative layer 3 .

[0038] Furthermore, the laminated structure of the present invention may be laminated with a non-combustible material layer, a heat absorbing layer, a heat reflecting layer, a heat shielding layer, a heat insulating layer, etc., to the extent that the effect of the present invention is not impaired. [Example]

[0039] The following examples will clarify the features of the present invention.

[0040] <Base material> Wood base material (rectangular laminated timber, height: 1200 mm, cross-sectional side length: 240 mm) <Thermal foam layer> A mixture containing 100 parts by weight of thermoplastic resin (acrylic resin), 90 parts by weight of melamine, 90 parts by weight of dipentaerythritol, 320 parts by weight of ammonium polyphosphate, and 100 parts by weight of titanium oxide as main components was kneaded in a pressure kneader set at a temperature of 120°C, and the mixture was layered on a nonwoven fabric and rolled using a pressure roller to produce a sheet-like thermally foamed layer (thickness: 2 mm).

[0041] <Cosmetic layer 1> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm): Back side (five recesses evenly spaced to form horizontal linear recesses when laminated onto the base material (Fig. 1), recess depth: 5mm (33% of thickness), recess width: 8mm, recess area: 3.3%) <Cosmetic layer 2> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm), backside (10 evenly spaced recesses to form horizontal lines when laminated onto the base material, recess depth: 5mm (33% of thickness), recess width: 4mm, recess area: 3.3%) <Cosmetic layer 3> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm), backside (20 evenly spaced recesses to form horizontal lines when laminated onto the base material, recess depth: 5mm (33% of thickness), recess width: 8mm, recess area: 13.3%) <Cosmetic layer 4> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 10mm): Back side (5 evenly spaced recesses to form horizontal linear depressions when laminated onto the base material, recess depth: 2.5mm (25% of thickness), recess width: 8mm, recess area: 3.3%) <Cosmetic layer 5> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 20mm), backside (five recesses evenly spaced to form horizontal linear depressions when laminated onto the base material, depression depth: 7mm (35% of thickness), depression width: 8mm, depression area: 3.3%) <Cosmetic layer 6> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm): Back side (evenly arranged so that when laminated to the base material, they form a lattice-shaped recess at a 45-degree angle (one side of the unit lattice: 171mm), recess depth: 5mm (33% of the thickness), recess width: 6mm, recess area: 6.9%) <Cosmetic layer 7> Woodblock (laminated wood board, height: 1200 mm, width: 242 mm, thickness: 15 mm): Back side (15 evenly spaced recesses to form circular recesses when laminated onto the base material (Fig. 4), recess depth: 5 mm (33% of thickness), recess diameter: 25 mm, recess area: 2.4%) <Cosmetic layer 8> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm), backside (five recesses evenly spaced to form horizontal linear depressions when laminated onto the base material, depth of depressions: 1.1mm (7.3% of thickness), width of depressions: 8mm, area occupied by depressions: 3.3%) <Cosmetic layer 9> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 20mm), backside (five recesses evenly spaced to form horizontal linear depressions when laminated onto the base material, depth of depressions: 9mm (45% of thickness), width of depressions: 8mm, area occupied by depressions: 3.3%) <Cosmetic layer 10> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm), backside (five recesses evenly spaced to form horizontal linear depressions when laminated onto the base material, depth of depressions: 5mm (33% of thickness), width of depressions: 4mm, area occupied by depressions: 1.7%) <Cosmetic layer 11> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm), backside (40 evenly spaced recesses to form horizontal linear depressions when laminated onto the base material, recess depth: 5mm (33% of thickness), recess width: 8mm, recess area: 26.7%) <Cosmetic layer 12> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm): Back side (5 evenly spaced recesses to form horizontal linear depressions when laminated onto the base material, recess depth: 0.5mm (3.3% of thickness), recess width: 8mm, recess area: 3.3%) <Cosmetic layer 13> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm), backside (five recesses evenly spaced to form horizontal linear depressions when laminated onto the base material, depth of depressions: 11mm (73.3% of thickness), width of depressions: 8mm, area occupied by depressions: 3.3%) <Cosmetic layer 14> Woodblock (laminated wood board, height: 1200mm, width: 242mm, thickness: 15mm), back side (no recess)

[0042] (Manufacturing of test specimens) A thermally foamed layer was laminated on all four side surfaces of the substrate via an adhesive, and a decorative layer (decorative layer 1) shown in Figure 1(b) was further laminated on the surface of the thermally foamed layer via an adhesive to form test piece 1. Furthermore, specimens 2 to 14 were prepared in the same manner as specimen 1, except that decorative layers 2 to 14 were used instead of decorative layer 1.

[0043] The prepared specimens 1 to 14 were subjected to a 60-minute heating test in accordance with the standard heating curve of ISO 834, during which the decorative layer was visually inspected for peeling. As a result, specimens 1 to 11 did not fall off even after 30 minutes had passed since the start of the test, and specimens 1 to 7 did not fall off even after 60 minutes had passed since the start of the test. In contrast, specimens 12 to 14 fell off 20 minutes after the start of the test.

Claims

1. A laminated structure having a thermal foaming layer on the surface side of a substrate and a decorative layer on the surface side of the thermal foaming layer, The back surface of the decorative layer has a recessed portion, The depth of the recess is 1 mm or more and 10 mm or less.

2. 2. The laminated structure according to claim 1, wherein the proportion of the recesses on the rear surface of the decorative layer is 1% to 30% of the entire rear surface of the decorative layer.

3. 2. The laminated structure according to claim 1, wherein the thickness of the decorative layer is 3 mm or more and 50 mm or less, and the depth of the recess on the back surface of the decorative layer is 5% or more and 45% or less of the thickness.

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