Forming base material

Abstract

To provide a substrate for molding a vehicle exterior material allowing attached snow and ice to easily fall off.SOLUTION: A substrate for molding 100 comprises a fiber substrate layer 10 including core-sheath type composite fibers with a sheath part made of polypropylene-based resin and a core part made of polyester-based resin. In the substrate for molding 100, the mass percentage of the core-sheath type composite fibers in the fibers constituting the fiber substrate layer 10 is more than 70 mass%.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a molding substrate. [Background technology]

[0002] Underbody shield material (hereinafter referred to as UBS), a type of exterior material, and wheelhouse liner material attached to the wheelhouse of the vehicle are installed on the underside of the vehicle for purposes such as reducing unevenness on the underside of the vehicle to suppress air resistance while driving, protecting the vehicle from stones thrown by the tires, and reducing road noise.

[0003] As a component of exterior materials such as UBS and wheelhouse liner materials, the applicant has previously studied molding substrates equipped with a fiber substrate layer containing sheath-core composite fibers in which the sheath is made of polypropylene resin and the core is made of polyester resin, as described in Japanese Patent Application No. 2019-208366 (Patent Document 1). Note that in Patent Document 1, the applicant stated the finding that the higher the mass percentage of sheath-core composite fibers in the fibers making up the fiber substrate layer, the more likely it is that an exterior material with excellent heat resistance can be provided, and from this perspective, the mass percentage is preferably 50 mass% or more. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent application 2019-208366 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in exterior materials such as UBS and wheelhouse liner materials prepared using a molding substrate satisfying the above-mentioned configuration, snow and ice that bounces off the road surface can adhere to the surface of the exterior material and be difficult to peel off. The snow or ice that remains attached to the exterior material can then freeze, and / or water from the road or rainwater can splash onto the snow or ice that remains attached to the exterior material and freeze again. When the snow or ice that has frozen to the exterior material peels off due to strong vibrations that occur during driving, it can cause cracks or internal peeling on the surface of the exterior material, which can lead to the destruction of the exterior material.

[0006] The exterior material destroyed in this way was found to no longer be able to satisfactorily exert its expected effects, such as reducing air resistance during driving, protecting the vehicle body, and reducing road noise.

[0007] In order to prevent the above-mentioned problems from occurring, there has been a demand for a molding substrate that can be used to produce exterior materials, such as exterior materials for vehicles, from which snow and ice that have adhered thereto can easily peel off. [Means for solving the problem]

[0008] The present invention provides a molding substrate having a fibrous substrate layer, the fibrous substrate layer including sheath-core composite fibers having a sheath made of a polypropylene resin and a core made of a polyester resin, the mass percentage of the sheath-core composite fibers being greater than 70 mass% of the fibers constituting the fibrous substrate layer. the fiber base material layer has a portion (a) including one of the main surfaces, a portion (b) including the other main surface, and a portion (c) sandwiched between the portion (a) and the portion (b), and the densities of the portions (a) and (b) are higher than the density of the portion (c); Molding substrate (with apparent density of 0.5 g / cm 3 (Except those above.) is. [Effects of the Invention]

[0009] As a result of continued research, the applicant of the present application found that the problem of snow and ice adhering to a molding substrate having a fiber substrate layer containing a core-sheath type composite fiber in which the sheath is made of a polypropylene-based resin and the core is made of a polyester-based resin, and that this problem of snow and ice being difficult to remove, can be solved by adjusting the mass percentage of the core-sheath type composite fiber in the fibers constituting the fiber substrate layer. Specifically, by providing a molding substrate having a fiber substrate layer with a mass percentage of more than 70 mass%, the molding substrate can be used to create exterior materials such as vehicle exterior materials that allow snow and ice to easily peel off.

[0010] Furthermore, as a result of continued research, the applicant of the present application has discovered that it is possible to provide a molding substrate that can be used to realize exterior materials such as exterior materials for vehicles that are more likely to have snow and ice attached thereto peel off, by having a high density in the portion including at least one main surface of the fiber substrate layer that the molding substrate is provided with.

[0011] The reason for this effect is that solids (snow and ice) and liquids (water and rainwater on the road surface) have difficulty passing through the high-density portion, making it difficult for the attached snow and ice, as well as water and rainwater on the road surface, to pass through the portion and penetrate into the fiber base material layer. As a result, it is believed that a molding base material can be provided that allows the attached snow and ice to remain on the surface of the exterior material, making it easier for the attached snow and ice to peel off.

[0012] Furthermore, by using a molding substrate that satisfies the configuration according to the present invention, it is possible to provide a molding substrate that has the secondary effect of realizing an exterior material that has excellent sound absorption and sound insulation performance and also has the property of being able to exhibit high rigidity even in a high-temperature atmosphere. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view showing a molding substrate according to the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view showing another molding substrate according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] In the present invention, various configurations can be appropriately selected, such as the following configurations. Note that, unless otherwise specified, the various measurements described in the present invention were performed under normal pressure and a temperature condition of 25°C. Furthermore, unless otherwise specified, the various measurement results described in the present invention were measured to a value one decimal place smaller than the desired value, and the value was calculated by rounding the value. Specifically, when the desired value is measured to one decimal place, the value was measured to two decimal places, and the obtained value was rounded to one decimal place to calculate the value to one decimal place, and this value was used as the desired value. Furthermore, the upper and lower limits exemplified in the present invention can be combined in any combination.

[0015] The present invention will be described mainly with reference to FIGS. 1 and 2, which are schematic cross-sectional views of the molding substrates (100, 200) according to the present invention.

[0016] The molding substrate (100, 200) includes a fiber substrate layer (10, 20). As will be described in detail later, the molding substrate (100) shown in FIG. 1 includes a portion (11a) including one main surface of the fiber substrate layer (10), a portion (11b) including the other main surface, and a portion (11c) sandwiched between the portions (11a) and (11b), with the density of the portion (11a) being higher than the density of the portion (11c). Also, as will be described in detail later, the molding substrate (200) shown in FIG. 2 includes a portion (21a) including one main surface of the fiber substrate layer (20), a portion (21b) including the other main surface, and a portion (21c) sandwiched between the portions (21a) and (21b), with the density of the portions (21a) and (21b) being higher than the density of the portion (21c).

[0017] The fibrous substrate layer (10, 20) referred to in the present invention refers to a layer of fibers formed by entanglement of fibers, such as a fibrous web, a nonwoven fabric, or a fabric such as a woven or knitted fabric. By including the fibrous substrate layer (10, 20), it is possible to provide a molding substrate (100, 200) that is highly flexible and easily conforms to a mold or the like, and therefore has excellent moldability. In order to provide a molding substrate (100, 200) with even better moldability, the fibrous substrate layer (10, 20) constituting the molding substrate (100, 200) is preferably a layer formed from a fibrous web or nonwoven fabric in which fibers are randomly entangled, and more preferably formed solely from a fibrous web or nonwoven fabric.

[0018] The fiber substrate layer (10, 20) contains a sheath-core composite fiber in which the sheath is made of a polypropylene-based resin and the core is made of a polyester-based resin. By including the sheath-core composite fiber in the fiber substrate layer (10, 20), it is possible to provide a molding substrate (100, 200) that can realize an exterior material that easily peels off adhering snow and ice.

[0019] The polypropylene-based resin constituting the sheath of the core-sheath composite fiber according to the present invention may be any known type, such as polypropylene, polymethylpentene, or polypropylene having a structure in which a portion of the hydrocarbon is substituted with a nitrile group or a halogen such as fluorine or chlorine, etc. The melting point of the polypropylene-based resin may be higher than 80°C, higher than 90°C, or higher than 100°C.

[0020] The polyester-based resin constituting the core of the sheath-core composite fiber according to the present invention may be any known type, such as polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polycarbonate, polyarylate, wholly aromatic polyester resin, etc. The melting point of the polyester-based resin may be higher than 80°C, higher than 90°C, or higher than 100°C. The melting point of the polyester-based resin constituting the core of the sheath-core composite fiber according to the present invention is higher than the melting point of the polypropylene-based resin constituting the sheath.

[0021] The area ratio of the core to the sheath in the fiber cross section of the core-sheath composite fiber can be adjusted as appropriate, but can be 1:9 to 9:1, 2:8 to 8:2, 3:7 to 7:3, or 4:6 to 6:4.

[0022] The various values ​​of the sheath-core composite fiber, such as fiber length and fineness, are appropriately adjusted to provide a molding substrate (100, 200) that can solve the problems of the present invention. The fineness can be 1 to 100 dtex, 1.5 to 50 dtex, 2 to 30 dtex, or 3 to 10 dtex.

[0023] Furthermore, it may be a fiber having a specific length, such as short fiber, and the fiber length may be 20 to 150 mm, 25 to 100 mm, 30 to 90 mm, or 40 to 80 mm.

[0024] The fibers may be fibers having a continuous length longer than 150 mm, making it difficult to specify the fiber length (a concept that includes constituent fibers of meltblown nonwoven fabrics and spunbond nonwoven fabrics). However, the core-sheath type composite fibers are preferably short fibers so that a molding substrate (100, 200) having a high-density main surface portion can be easily prepared.

[0025] The core-sheath type composite fiber may be a fiber prepared by kneading a pigment into the fiber or a dyed fiber.

[0026] When the mass percentage of the core-sheath composite fibers according to the present invention in the fibers constituting the fiber substrate layer (10, 20) is greater than 70 mass%, a molding substrate (100, 200) can be provided that can realize an exterior material from which snow and ice adhere to it easily peel off. This value can be adjusted as appropriate as long as it is greater than 70 mass%, and can be 75 mass% or more, preferably 80 mass% or more. Note that if all of the constituent fibers of the fiber substrate layer (10, 20) are core-sheath composite fibers (this value is 100 mass%), it is even more preferable to provide a molding substrate (100, 200) that can realize an exterior material from which snow and ice adhere to it easily peel off.

[0027] In the present invention, the mass percentage (unit: mass %) of the core-sheath type composite fibers in the fibers constituting the fibrous substrate layers (10, 20) can be calculated by the following formula. X=100×B / A X: Mass percentage of core-sheath type composite fibers in the fibers constituting the fiber substrate layer (10, 20) (unit: mass%) A: Mass of the fibers constituting the fiber substrate layer (10, 20) (unit: g / m 2 ) B: Mass of core-sheath composite fiber contained in the fiber substrate layer (10, 20) (unit: g / m 2 )

[0028] The mass of the fibers constituting the fibrous substrate layer (10, 20) and the mass of the core-sheath composite fibers contained in the fibrous substrate layer (10, 20) can be determined by extracting fibers from the fibrous substrate layer (10, 20) and using known analytical devices and methods, such as analysis using various analytical devices such as a melting point analyzer or FT-IR, optical analysis using an electron microscope, or dye analysis using Kayastain dye. Specifically, 100 fibers are randomly extracted from the fibrous substrate layer (10, 20), and the mass (A) of the 100 fibers is measured. Then, the mass (B) of the core-sheath composite fibers contained in the 100 fibers is measured using the well-known analytical devices and methods described above.

[0029] Alternatively, 5 g (mass (A)) of fibers is randomly extracted from the fiber substrate layer (10, 20). Then, the mass (B) of the core-sheath type composite fibers contained in the 5 g of fibers is measured using the well-known analytical device and analytical method described above.

[0030] From the masses thus determined, the mass percentage (X) of the core-sheath type composite fibers in the fibers constituting the fibrous substrate layers (10, 20) can be determined.

[0031] Furthermore, when the manufacturing process is known, the mass of the fibers constituting the fibrous substrate layer (10, 20) and the mass of the core-sheath type composite fiber contained in the fibrous substrate layer (10, 20) can be determined by confirming the types and masses of the fibers blended to prepare the fibrous substrate layer (10, 20).

[0032] It is preferable that the core-sheath type composite fibers are uniformly distributed in the fiber substrate layer (10, 20). Specifically, it is preferable that the mass percentage (X) of the portion (11a, 21a) including one of the main surfaces of the fiber substrate layer (10, 20), the mass percentage (X) of the portion (11b, 21b) including the other main surface of the fiber substrate layer (10, 20), and the mass percentage (X) of the portion (11c, 21c) sandwiched between the two portions (11a and 11b, 21a and 21b) are the same. A fiber substrate layer (10, 20) of this type is preferable because it can provide a molding substrate (100, 200) that can more efficiently realize an exterior material that easily peels off adhering snow and ice.

[0033] In addition to the core-sheath type composite fibers, the fiber substrate layers (10, 20) may also contain other organic fibers made from one type of organic resin, other organic fibers made from multiple types of organic resins, and inorganic fibers such as glass fibers.

[0034] Examples of such other organic fibers include polyolefin resins (e.g., polyethylene, polypropylene, polymethylpentene, polyolefin resins having a structure in which part of the hydrocarbon is substituted with a nitrile group or a halogen such as fluorine or chlorine, etc.), styrene resins, polyvinyl alcohol resins, polyether resins (e.g., polyether ether ketone, polyacetal, modified polyphenylene ether, aromatic polyether ketone, etc.), polyester resins (e.g., polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polycarbonate, polyarylate, wholly aromatic polyester resin, etc.), polyimide resins, poly Examples of suitable organic resins include amide-imide resins, polyamide-based resins (e.g., aromatic polyamide resins, aromatic polyetheramide resins, nylon resins, etc.), resins having nitrile groups (e.g., polyacrylonitrile, etc.), urethane-based resins, epoxy-based resins, polysulfone-based resins (e.g., polysulfone, polyethersulfone, etc.), fluorine-based resins (e.g., polytetrafluoroethylene, polyvinylidene fluoride, etc.), cellulose-based resins, polybenzimidazole resins, and acrylic-based resins (e.g., polyacrylonitrile-based resins copolymerized with acrylic esters or methacrylic esters, modacrylic resins copolymerized with acrylonitrile and vinyl chloride or vinylidene chloride). The organic resins can be formed using known organic resins.

[0035] These organic resins may be either linear or branched polymers, may be block or random copolymers, may have any three-dimensional structure, may have any crystallinity, or may be a mixture of multiple organic resins.

[0036] These organic resins may also contain additives such as flame retardants, fragrances, pigments, antibacterial agents, antifungal materials, photocatalytic particles, emulsifiers, dispersants, surfactants, particles that foam when heated, inorganic particles, and antioxidants.

[0037] The fibers constituting the fibrous base material layer (10, 20) may include irregular cross-section fibers in addition to substantially circular and elliptical fibers. The irregular cross-section fibers may have a cross section of a hollow shape, a polygonal shape such as a triangular shape, an alphabetic shape such as a Y-shape, an irregular shape, a multi-lobed shape, a symbolic shape such as an asterisk shape, or a shape combining multiple of these shapes.

[0038] The fibrous substrate layers (10, 20) can be prepared by, for example, a dry method in which fibers are fed into a carding device or an air-laying device to entangle the fibers; a wet method in which fibers are dispersed in a solvent and then entangled in a sheet; or a method in which fibers are spun using a direct spinning method (such as a melt-blowing method, a spunbonding method, an electrospinning method, or a method in which a spinning solution and a gas stream are discharged in parallel to each other to spin the fibers (for example, the method disclosed in JP 2009-287138 A)) and the fibers are collected.

[0039] Furthermore, the constituent fibers can be entangled and / or integrated. Examples of methods for entangling and / or integrating the constituent fibers include entanglement using needles or a water jet, and a method in which the constituent fibers are bonded or melted together using a binder or adhesive fiber by subjecting the fiber web to heat treatment.

[0040] The heat treatment method can be appropriately selected, and examples thereof include a method of heating or heating and pressurizing with a roll, a method of heating by subjecting to a heater such as an oven dryer, a far-infrared heater, a dry heat dryer, or a hot air dryer, and a method of irradiating infrared rays without pressure to heat the resin contained therein.

[0041] A binder may be used to bond the constituent fibers of the fibrous base layer (10, 20). The type of binder that can be used is appropriately selected, and examples of binders that can be used include polyolefins (such as modified polyolefins), ethylene-vinyl alcohol copolymers, ethylene-acrylate copolymers such as ethylene-ethyl acrylate copolymers, various rubbers and their derivatives (such as styrene-butadiene rubber (SBR), fluororubbers, urethane rubbers, and ethylene-propylene-diene rubber (EPDM)), cellulose derivatives (such as carboxymethyl cellulose (CMC), hydroxyethyl cellulose, and hydroxypropyl cellulose), polyvinyl alcohol (PVA), polyvinyl butyral (PVB), polyvinylpyrrolidone (PVP), epoxy resins, polyvinylidene fluoride (PVdF), vinylidene fluoride-hexafluoropropylene copolymers (PVdF-HFP), acrylic resins (such as acrylic ester resins and acrylonitrile-styrene copolymer resins), and polyurethane resins.

[0042] However, it is preferable that the fiber substrate layers (10, 20) are binder-free so that molding substrates (100, 200) that exhibit the intended effects of the present invention can be prepared.

[0043] The fibrous substrate layer (10, 20) can also be prepared using woven or knitted fabrics prepared by weaving or knitting the above-mentioned fibers. The fibrous substrate layer (10, 20) can also be prepared by subjecting a fabric such as a woven or knitted fabric to the above-mentioned method of entangling and / or integrating the constituent fibers.

[0044] The various configurations of the fiber substrate layer (10, 20), such as thickness and basis weight, are not particularly limited and may be adjusted as appropriate. The thickness may be 0.2 to 15 mm, 0.3 to 10 mm, or 1 to 3 mm. The basis weight may be, for example, 30 to 2000 g / m 2 and can be 40 to 1500 g / m 2 In particular, the basis weight can be 800 g / m 2The molding substrate (100, 200) having a larger number of fiber substrate layers (10, 20) is preferable because it has excellent bending strength and tensile strength in a high-temperature atmosphere, and has a basis weight of 900 g / m 2 It is more preferable that the molding substrate (100, 200) comprises the above-mentioned fiber substrate layer (10, 20). In the present invention, the thickness is 20 g / cm in the direction perpendicular to the main surface. 2 It refers to the length in the vertical direction when a compressive load is applied, and the basis weight is the weight per square meter on the surface (principal surface) with the widest area of ​​the object being measured. 2 This refers to the mass per unit mass.

[0045] In another aspect of the present invention, the fiber base material layer (10, 20) has a portion (11a, 21a) including one of the main surfaces, a portion (11b, 21b) including the other main surface, and a portion (11c, 21c) sandwiched between the portion (11a, 21a) and the portion (11b, 21b), and is characterized in that at least the density of the portion (11a, 21a) is higher than the density of the portion (11c, 21c).

[0046] By the fiber substrate layer (10, 20) according to the present invention satisfying the above constitution, it is possible to provide a molding substrate (100, 200) that can realize an exterior material from which snow and ice adhering thereto easily peel off.

[0047] The reason for this is that solids (snow and ice) and liquids (water and rainwater on the road surface) have difficulty passing through the high-density portions (11a, 21a), and therefore the attached snow and ice as well as the water and rainwater on the road surface have difficulty passing through the portions (11a, 21a) and penetrating into the interior (11c, 21c) of the fiber base material layer (10, 20).

[0048] As a result, it is believed that it is possible to provide a molding substrate (100, 200) that allows for the realization of an exterior material in which the snow and ice that has adhered thereto only adheres to the surface of the exterior material and from which the adhered snow and ice easily peels off.

[0049] It is preferable that the main surface of the molding substrate (100, 200) on the side of the portions (11a, 21a) faces the side on which snow, ice, water or rainwater adheres when used as an exterior material.

[0050] Furthermore, by using a fiber base material layer (10, 20) that satisfies the configuration of the present invention, it is possible to provide a molding base material (100, 200) that has the secondary effect of realizing an exterior material that has excellent sound absorption and sound insulation properties and also has the property of being able to exhibit high rigidity even in a high-temperature atmosphere.

[0051] The density of the portion (11a, 21a) including one of the main surfaces of the fiber base material layer (10, 20), the density of the portion (11b, 21b) including the other main surface, and the density of the portion (11c, 21c) sandwiched between the portions (11a, 21a) and (11b, 21b) can be confirmed using the following comparison method.

[0052] (Density comparison method) 1. An electron microscope photograph is taken of a cross section in the thickness direction of the fiber substrate layer (10, 20) constituting the molding substrate (100, 200). At this time, the magnification is adjusted so that the entire thickness direction of the fiber substrate layer (10, 20) is captured in the electron microscope photograph. 2. On the electron microscope photograph, draw a line segment that connects one main surface (for example, the main surface on the upper side of the paper in Figure 1 or Figure 2) and the other main surface (for example, the main surface on the lower side of the paper in Figure 1 or Figure 2) over the shortest distance, parallel to the thickness direction of the molding substrate (100, 200). 3. On the electron microscope photograph, draw two lines (A1, A2) that pass through the ends of the line segment and are perpendicular to it. Furthermore, draw two more lines (B1, B2) that are perpendicular to the line segment and divide it into thirds. 4. The range between the line (A1) and the line (B1) that divides the line segment into thirds and is closest to the line (A1) is defined as range a. 5. The range between the line (A2) and the line (B2) that is closest to the line (A2) among the lines that divide the line segment into thirds is defined as range b. 6. Let the range between the lines (B1, B2) be range c. 7. Calculate the percentage a of the area of ​​components that make up the fiber base layer (10, 20), such as fibers and binders, relative to the cross-sectional area of ​​the fiber base layer (10, 20) that appears in the range a. 8. Calculate the percentage b of the area of ​​components that make up the fiber base layer (10, 20), such as fibers and binders, relative to the cross-sectional area of ​​the fiber base layer (10, 20) that appears in the range b. 9. Calculate the percentage c of the area of ​​components that make up the fiber base layer (10, 20), such as fibers and binders, relative to the cross-sectional area of ​​the fiber base layer (10, 20) that appears in the range c. When percentage a calculated as described above is higher than percentage c, it can be determined that the density of the portion (11a, 21a) including one of the main surfaces of the fiber base material layer (10, 20) is higher than the density of the portion (11c, 21c) sandwiched between the portion (11a, 21a) and the portion (11b, 21b) including the other main surface.

[0053] Furthermore, when percentages a and b calculated as described above are both higher than percentage c, it can be determined that the densities of the portion (11a, 21a) including one main surface of the fiber base material layer (10, 20) and the portion (11b, 21b) including the other main surface are both higher than the density of the portion (11c, 21c) sandwiched between the portions (11a, 21a) and (11b, 21b).

[0054] In the molding substrate (100) according to the present invention, only the portion (11a) including one of the main surfaces of the fiber substrate layer (10) may be a high-density portion, as shown in Fig. 1. The molding substrate (100) having such a fiber substrate layer (10) can provide a molding substrate (100) that more effectively achieves the secondary effect of realizing an exterior material with better sound absorption performance, sound insulation performance, and rigidity.

[0055] In addition, in another molding substrate (200) according to the present invention, as shown in Fig. 2, in addition to the portion (21a) including one main surface of the fiber substrate layer (20), the portion (21b) including the other main surface (the main surface located on the lower side of the paper in Fig. 2) opposite to the portion (21a) may also be a high-density portion. A molding substrate (200) including such a fiber substrate layer (20) can be provided that more effectively achieves the secondary effect of realizing an exterior material with better sound absorption performance, sound insulation performance, and rigidity.

[0056] The method for forming the high-density portions (11a, 21a, 21b) including the main surfaces in the fiber base material layers (10, 20) can be adjusted as appropriate. For example, there can be mentioned a method of applying heat or heat and pressure to the main surfaces of the fabric using a heating roll to densify the portions including the main surfaces, a method of applying heat or heat and pressure to the main surfaces of the fabric using a heating roll to melt the portions including the main surfaces into a porous film to densify them, a method of applying a binder or additive to the main surfaces of the fabric to densify the portions including the main surfaces, and a method of applying hydroentanglement or needle punching to the main surfaces of the fabric to increase the fiber density to densify the portions including the main surfaces.

[0057] In particular, it is preferable that the sheath portion of the core-sheath composite fiber constituting the main surface is melted to form a portion (11a, 21a, 21b) including the high-density main surface. The melted sheath portion on the main surface closes some of the voids present on the main surface, reducing air permeability and increasing density, and further, the melted sheath portion on the main surface becomes a porous film, reducing air permeability and increasing density, making it possible to provide a molding substrate (100, 200) that more effectively exerts the secondary effect of realizing an exterior material with better sound absorption performance, sound insulation performance, and rigidity.

[0058] The densified portions of the fiber base material layers (10, 20) are portions with reduced breathability.

[0059] When the breathability of the portion including the main surface is reduced and the density is increased, it is preferable to apply heat and pressure simultaneously. If only heat is applied to the main surface of the fabric without applying pressure, the portion including the main surface may not be sufficiently densified. Furthermore, even if only heat is applied to the main surface of the fabric and then a heating roll is applied to the main surface of the fabric to apply heat and pressure, the portion including the main surface may remain insufficiently densified.

[0060] As a result, it may be difficult to provide a molding substrate (100, 200) that also has excellent sound absorption properties (specifically, sound absorption properties in a frequency band below 2000 Hz).

[0061] Therefore, in the heat treatment for reducing the air permeability and increasing the density of the portion including the main surface, it is more preferable to initially apply heat and pressure simultaneously as the heat treatment to be applied to the fabric.

[0062] The thickness of the molding substrate (100, 200) is appropriately selected, but can be 20 mm or less, 10 mm or less, or 5 mm or less. On the other hand, the lower limit of the thickness can be adjusted appropriately, but a practical value is 0.5 mm or more. The basis weight of the molding substrate (100, 200) can be appropriately selected, but is preferably 2000 g / m 2 and 1500 g / m 2 On the other hand, the lower limit of the basis weight is adjusted appropriately, but it is not more than 10 g / m 2 More than 50g / m is practical. 2 It is preferable that the thickness is 100 g / m or more. 2 More preferably, it is equal to or greater than this.

[0063] The molding substrate (100, 200) of the present invention may further comprise a cover material such as another porous body, film, or foam. The type of cover material can be appropriately selected depending on the physical properties required of the molding substrate, and can be, for example, a fabric, a porous or non-porous film, a porous or non-porous foam, or the like. The various configurations of the cover material, such as basis weight, thickness, and porosity, can be appropriately selected depending on the desired physical properties. In particular, a spunbond nonwoven fabric is preferred because it can easily provide a molding substrate that can realize an exterior material that easily peels off attached snow and ice. Furthermore, a molding substrate (100, 200) having spunbond nonwoven fabric on both main surfaces is preferred because it can easily provide a molding substrate that can realize an exterior material that easily peels off attached snow and ice.

[0064] The method for providing the cover material on the molding substrate (100, 200) can be selected as appropriate, and may include an embodiment in which the cover material is bonded to the molding substrate (100, 200) using a binder, an embodiment in which the main surface of the molding substrate (100, 200) is melted and the cover material is laminated thereon, thereby bonding the cover material to the components constituting the main surface (for example, the sheath portion of a core-sheath composite fiber), and an embodiment in which the main surface of the cover material is melted and laminated thereon to the molding substrate (100, 200), thereby bonding the cover material to the components constituting the main surface.

[0065] The molding substrate may have a print layer on its main surface, and a top coat layer on the print layer. The print layer is a resin layer that exists on at least one main surface of the molding substrate and primarily serves to improve the design and / or tactile feel of the molding substrate. The print layer may contain the additives mentioned above in addition to the resin. The molding substrate may have only one type of print, or may have multiple types of prints that differ in composition, such as the type of resin that makes up the print, the type of pigment, or the presence or absence of pigment. The form of the top coat can also be adjusted as appropriate, and the top coat may be present on the entire main surface, or may be present only partially.

[0066] The topcoat layer refers to a resin layer present on at least one of the main surfaces of the molding substrate, and primarily serves to protect the main surface of the molding substrate. The topcoat layer may contain the above-mentioned additives in addition to the resin. The molding substrate may have only one type of topcoat, or may have multiple types of topcoats with different formulations, such as the type of resin that constitutes the topcoat. The form of its presence can also be adjusted appropriately, and it may be present on the entire main surface or partially present.

[0067] The type of resin constituting the print and top coat layer can be appropriately selected, and the same resin as the binder described above can be used. In particular, it is preferable to use an acrylic resin, since it softens appropriately during thermoforming such as heat pressing using a mold, conforms to the mold, and can provide a molding substrate with excellent formability. [Example]

[0068] The present invention will be specifically described below with reference to examples, but these are not intended to limit the scope of the present invention. The molding substrates prepared in the examples and comparative examples were subjected to the following evaluation methods to confirm their physical properties.

[0069] (Evaluation method for ice peeling) A square-shaped sample (150 mm on each side) was taken from the molding substrate, and an ice adhesion tester was installed on one or the other of the sample's main surfaces. The ice adhesion tester was a cylindrical jig (outer diameter: 48.6 mm, inner diameter: 44 mm, height: 30 mm, thickness: 2.3 mm, with a ring on the outer periphery) prepared using the STK500 material disclosed in JIS G3444:2015, and the end of the cylinder was installed facing the main surface of the sample. When the molding substrate had a main surface derived from a spunbond nonwoven fabric, the end of the cylinder was installed facing the main surface of the sample. The test piece was then left in a test room at -15°C for at least one hour with the main surface on which the ice adhesion test device was installed facing the opposite side to the direction of gravity. While the device was left in the test room, 5 ml of 3°C distilled water was poured into the inside of the ice adhesion force test device and left for 15 minutes to freeze the distilled water. After freezing, another 5 ml of 3°C distilled water was poured in and left to freeze the distilled water. After freezing for 30 minutes, another 5 ml of 3°C distilled water was poured in and left to freeze the distilled water for 30 minutes. Then, 15 ml of 3°C distilled water was poured in and left to freeze the distilled water for 3 hours. Then, while the sample was still fixed, a force gauge with a 500 mm wire attached was placed on the ring part of the ice adhesion force measuring device, and the wire was pulled up in the opposite direction to gravity until the ice adhesion force measuring device was peeled off from the sample.

[0070] If the maximum peel strength measured before the ice adhesion force measuring device peeled off the sample was 25 N or less, the molding substrate was evaluated as having excellent ice release properties and was rated as "○", and if it was higher than 25 N, the molding substrate was evaluated as having poor ice release properties and was rated as "×".

[0071] (Method for evaluating bending strength under high temperature conditions) Using a measuring instrument specified in JIS K7171, "How to Determine the Bending Properties of Plastics," a sample (length: 150 mm, width: 50 mm) taken from the molding substrate was left in an 80°C atmosphere for 1 hour, then placed with a support distance of 100 mm, and a load was applied to the center of the supports at a rate of 50 mm / min using an indenter with a tip radius of 5 mm. The maximum point load was calculated as the heat resistance bending rigidity value from the load and deflection at this time.

[0072] When the heat resistance bending rigidity value obtained by measurement was 10 N / 50 mm or more, it was evaluated as "○" because it was excellent in bending strength in a high-temperature atmosphere, and when it was less than 10 N / 50 mm, it was evaluated as "×" because it was poor in bending strength in a high-temperature atmosphere.

[0073] (Method for evaluating tensile strength) The specimens were cut from the molding substrate into test pieces in the shape of a No. 1 dumbbell as specified in JIS K6251, and attached to a tensile tester with a chuck distance of 90 mm. The maximum point load was measured at a tension speed of 200 mm / min to determine the tensile strength.

[0074] Those having a tensile strength of 285 N / cm or more were evaluated as having excellent tensile strength and marked with "◯", and those having a tensile strength of less than 285 N / cm were evaluated as having poor tensile strength and marked with "×".

[0075] (Sound absorption evaluation method) Samples taken from the molding substrate were used in a Brüel & Kjær normal incidence sound absorption meter to measure the normal incidence sound absorption coefficient in the frequency range of 500 Hz to 6300 Hz in accordance with ISO 354. When measuring the sound absorption coefficient, the molding substrate was placed in a small high-frequency sound tube, and an air layer was placed behind the molding substrate as seen from the sound source, so that the total thickness of the molding substrate (diameter: 28 mm, thickness: 5 mm) and the air layer was 15 mm. Furthermore, if the molding substrate had a main surface made of spunbond nonwoven fabric, the measurement was performed with that main surface exposed to the sound wave generation side.

[0076] Of the measured molding substrates, those with a sound absorption coefficient of 40% or more at 1000 kHz, 55% or more at 1600 Hz, and 65% or more at 2000 Hz were evaluated as having excellent sound absorption and marked with "○" for each frequency. In addition, those with a lower sound absorption coefficient than the above were evaluated as having poor sound absorption and marked with "×" for each frequency.

[0077] (Type of fiber used) -Sheath-core composite fiber (fineness: 4.4 dtex, fiber length: 51 mm, core: polyethylene terephthalate (melting point: 258°C), sheath: polypropylene (melting point: 163°C)): hereafter referred to as PET / PP sheath-core composite fiber. Polyethylene terephthalate fiber 1 (fineness: 6.6 dtex, fiber length: 76 mm, melting point: 258°C): hereinafter referred to as PET single fiber. Polyethylene terephthalate fiber 2 (fineness: 4.4 dtex, fiber length: 51 mm, core: polyethylene terephthalate (melting point: 258°C), sheath: low-melting-point polyethylene terephthalate (melting point: 163°C)): hereafter referred to as PET / Lo-PET core-sheath composite fiber.

[0078] Example 1 A fiber web was prepared by feeding the PET / PP core-sheath composite fiber into a carding machine, and then needle-punched from one main surface of the fiber web to the other main surface to prepare a needle-punched web. The needle-punched web was subjected to a heating roll adjusted to a heating temperature of 190°C, and the heating roll was applied to both main surfaces of the needle-punched web, thereby simultaneously applying heat and pressure. The nonwoven fabric thus prepared was used as a substrate (basis weight: 1200 g / m 2 The substrate was then heated in a far-infrared heating furnace with the heating temperature adjusted to 210°C, and then molded using a cold press to obtain a molding substrate (basis weight: 1200 g / m 2 , thickness: 5 mm) was prepared. The portions of the molding substrate including both main surfaces (corresponding to 21a and 21b in Figure 2) were porous film-like and had high density due to the melting of the sheath, and both had higher densities than the portions sandwiched between the two portions (corresponding to 21c in Figure 2).

[0079] Example 2 Spunbond nonwoven fabric made of polyethylene terephthalate resin (basis weight: 35 g / m 2 ) were prepared. The spunbond nonwoven fabric was placed on both main surfaces of the needle-punched web prepared in Example 1, and the web was subjected to heating rolls adjusted to a heating temperature of 190°C. Heat and pressure were simultaneously applied to both main surfaces of the needle-punched web using the heating rolls, with the spunbond nonwoven fabric interposed therebetween, to form a base material (basis weight: 1270 g / m 2 The substrate was then heated in a far-infrared heating furnace with the heating temperature adjusted to 210°C, and then molded using a cold press to obtain a molding substrate (basis weight: 1270 g / m2 , thickness: 5 mm) was prepared. Furthermore, the portions of the fiber substrate layer derived from the needle-punched web including both main surfaces (corresponding to 21a and 21b in Figure 2) were porous film-like due to the melting of the sheath portion and had a high density similar to Example 1, and both had a higher density than the portion sandwiched between the two portions (corresponding to 21c in Figure 2).

[0080] Example 3 A fiber web was prepared by blending 80% by mass of PET / PP core-sheath composite fibers and 20% by mass of PET monofilaments and feeding the blend into a carding machine. A molding substrate (basis weight: 1270 g / m) was prepared in the same manner as in Example 2, except that the fiber web prepared in this manner was used. 2 , thickness: 5 mm) was prepared. Furthermore, the portions including both main surfaces of the fiber substrate layer derived from the needle-punched web (corresponding to 21a and 21b in Figure 2) were porous film-like due to the melting of the sheath portion, and although not as dense as in Examples 1 and 2, the densities were higher than those of the portions sandwiched between the two portions (corresponding to 21c in Figure 2).

[0081] (Comparative Example 1) A fiber web was prepared by blending 70% by mass of PET / PP core-sheath composite fibers and 30% by mass of PET monofilaments and feeding the blend into a carding machine. A molding substrate (basis weight: 1270 g / m) was prepared in the same manner as in Example 2, except that the fiber web prepared in this manner was used. 2 , thickness: 5 mm) was prepared. Furthermore, the portions including both main surfaces of the fiber base material layer derived from the needle-punched web (corresponding to 21a and 21b in Figure 2) were porous film-like due to the melting of the sheath portion, and although not as dense as in Examples 1 to 3, the densities were all higher than the densities of the portions sandwiched between the two portions (corresponding to 21c in Figure 2).

[0082] (Comparative Example 2) A molding substrate (basis weight: 1270 g / m) was prepared in the same manner as in Example 2, except that PET / Lo-PET core-sheath composite fiber was used instead of PET / PP core-sheath composite fiber.2 , thickness: 5 mm) was prepared. Furthermore, the portions of the fiber substrate layer derived from the needle-punched web including both main surfaces (corresponding to 21a and 21b in Figure 2) were porous film-like due to the melting of the sheath portion and had a high density similar to Example 1, and both had a higher density than the portion sandwiched between the two portions (corresponding to 21c in Figure 2).

[0083] In Examples 2 and 3 and Comparative Examples 1 and 2, the needle-punched web and the spunbonded nonwoven fabric were fiber-bonded together by the molten sheath component.

[0084] The composition and evaluation results of various physical properties of the molding substrates prepared as described above are summarized in Table 1. Items not provided are marked with "-" in the table.

[0085] [Table 1]

[0086] The molding substrates of Examples 1 to 3, which satisfy the configuration of the present invention, were excellent in ice releasability, and therefore were molding substrates that could be used to realize exterior materials from which snow and ice adhered thereto easily peel off. Furthermore, the molding substrates were also excellent in bending strength, tensile strength, and sound absorption properties in a high-temperature atmosphere, and therefore were molding substrates that could be used to realize exterior materials that had high rigidity and excellent sound absorption performance. On the other hand, the molding substrates of Comparative Examples 1 and 2, which did not satisfy the configuration of the present invention, were poor in ice releasability, and therefore were molding substrates that could not be used to realize exterior materials from which snow and ice adhered thereto easily peel off.

[0087] Furthermore, from the results of comparing Example 2 with Comparative Example 2, it was found that the molding substrate according to the present invention was equipped with a fiber substrate layer containing core-sheath type composite fibers in which the sheath was made of a polypropylene-based resin and the core was made of a polyester-based resin, and therefore had excellent bending strength in a high-temperature atmosphere, and was therefore a molding substrate that could be used to realize an exterior material from which snow and ice adhering thereto easily peel off.

[0088] Furthermore, from the results of comparing Examples 2 and 3 with Comparative Example 1, it was found that the molding substrate according to the present invention has a mass percentage of the core-sheath composite fibers in the fibers constituting the fiber substrate layer that is greater than 70 mass %, and therefore has excellent bending strength in a high-temperature atmosphere and can exhibit high rigidity even in a high-temperature atmosphere, making it a molding substrate that can be used to realize an exterior material from which snow and ice that has adhered thereto easily peels off.

[0089] Example 4 A molding substrate (basis weight: 870 g / m) was prepared in the same manner as in Example 2, except that a lightweight fiber web was used. 2 , thickness: 5 mm) was prepared.

[0090] Example 5 A molding substrate (basis weight: 970 g / m) was prepared in the same manner as in Example 2, except that a lightweight fiber web was used. 2 , thickness: 5 mm) was prepared.

[0091] Example 6 Spunbond nonwoven fabric made of polyethylene terephthalate resin (basis weight: 35 g / m 2 ) was prepared. The spunbond nonwoven fabric was placed on one main surface of the needle-punched web prepared in Example 1, and the web was subjected to a heating roll adjusted to a heating temperature of 190°C. Heat and pressure were simultaneously applied to both main surfaces of the needle-punched web using the heating roll, with the spunbond nonwoven fabric interposed therebetween, to form a base material (basis weight: 1235 g / m 2 The substrate was then heated in a far-infrared heating furnace with the heating temperature adjusted to 210°C, and then molded using a cold press to obtain a molding substrate (basis weight: 1235 g / m 2 , thickness: 5 mm) was prepared.

[0092] In Examples 4 to 6, the portions of the fibrous base material layer derived from the needle-punched web that included both main surfaces (corresponding to 21a and 21b in Figure 2) were porous film-like due to the melting of the sheath portion and had a high density similar to Example 2, and in each case, the density was higher than that of the portion sandwiched between the two portions (corresponding to 21c in Figure 2).The needle-punched web and the spunbonded nonwoven fabric were fiber-bonded by the melted sheath component.

[0093] The composition and evaluation results of various physical properties of the molding substrates prepared as described above are summarized in Table 2. Items not provided are marked with "-" in the table. For ease of understanding, the results of Example 2 are also listed.

[0094] [Table 2]

[0095] The molding substrates of Examples 4 to 6 were excellent in ice peeling properties, and were molding substrates that could be used to realize exterior materials from which adhering snow and ice easily peeled off.

[0096] Furthermore, from the results of comparing Example 4 with Example 5 and Example 2, it was found that the basis weight was 800 g / m 2 It was found that a molding substrate having a larger number of fiber substrate layers has excellent bending strength and tensile strength in a high temperature atmosphere.

[0097] From the above, it has been found that the present invention can provide a molding substrate that can realize an exterior material from which snow and ice adhering thereto can easily peel off.

[0098] It has also been found that a molding base material that satisfies the configuration according to the present invention can provide a molding base material that has the secondary effect of realizing an exterior material that is excellent in sound absorption performance, sound insulation performance, and rigidity. [Industrial Applicability]

[0099] The molding substrate of the present invention can be suitably used as a constituent member of an interior or exterior material. [Explanation of symbols]

[0100] 100, 200... Base material for molding 10, 20...Fiber base layer 11a, 21a: A portion including one main surface of the fiber base material layer 11b, 21b: Portion including the other main surface of the fiber base material layer 11c, 21c: A portion of the fiber base material layer sandwiched between a portion including one main surface and a portion including the other main surface

Claims

[Claim 1] A molding substrate having a fiber substrate layer, the fiber substrate layer contains core-sheath type composite fibers in which the sheath is a polypropylene-based resin and the core is a polyester-based resin, the mass percentage of the core-sheath type composite fibers in the fibers constituting the fiber substrate layer is more than 70 mass%, The fiber base material layer has a portion (a) including one main surface, a portion (b) including the other main surface, and a portion (c) sandwiched between the portion (a) and the portion (b), and the densities of the portions (a) and (b) are higher than the density of the portion (c); Molding substrate (however, the apparent density is 0.5 g / cm ３ (Except for those that are above this limit).

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