Molding sheets and molded bodies

Abstract

To provide a sheet for molding that is suitable for various uses.SOLUTION: A sheet for molding includes a nonwoven fabric 1 and a resin layer 2 laminated on the nonwoven fabric. The nonwoven fabric has an elongation at break at 130°C of 100% or more and a stress at 5% elongation of 10 N / 5 cm or more. The resin layer includes an impregnation part 3 and a non-impregnation part 4. The impregnation part 3 includes a resin with a number average molecular weight of 5,000 or more and 150,000 or less, the nonwoven fabric being impregnated with the impregnation part 3, while the nonwoven fabric not being impregnated with the non-impregnation part 4.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a molding sheet having a resin layer, and a molded body. [Background technology]

[0002] Various molding sheets have been known in the past. For example, Patent Document 1 discloses a spunbond nonwoven fabric suitable for thermoforming applications, which contains polyethylene terephthalate and a thermoplastic polystyrene copolymer. Furthermore, Patent Document 2 discloses a spunbond nonwoven fabric suitable for thermoforming applications, which has a shrinkage rate of 5% or less in the elongation direction after being stretched to 150% in an atmosphere at 130°C and then left for 30 minutes in an atmosphere at 20°C. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-222950 [Patent Document 2] Japanese Patent Application Publication No. 2017-222951 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Documents 1 and 2 describe that spunbond nonwoven fabrics suitable for thermoforming are used as coffee filter materials, etc. In recent years, there has been a growing demand for the application of molding sheets to a variety of other uses.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a molding sheet that can be easily used for various purposes. [Means for solving the problem]

[0006] The molding sheet according to the present invention is [1] a molding sheet comprising a nonwoven fabric and a resin layer laminated on the nonwoven fabric, wherein the nonwoven fabric has a breaking elongation of 100% or more at 130°C and a stress at 5% elongation of 10 N / 5 cm or more, and the resin layer contains a resin with a number average molecular weight of 5,000 or more and 150,000 or less, and wherein the molding sheet has an impregnated portion where the nonwoven fabric is impregnated and an unimpregnated portion where the nonwoven fabric is not impregnated. This configuration makes it possible to provide a molding sheet that is easy to use for a variety of applications.

[0007] Furthermore, preferred embodiments of the molding sheet according to the present invention are as follows. [2] The molding sheet according to [1], wherein the resin is at least one selected from the group consisting of polyester-based resins, polyester urethane-based resins, polyamide-based resins, polyamide-imide-based resins, phenoxy-based resins, olefin-based resins, and acrylic-based resins. [3] The molding sheet according to [1] or [2], wherein the resin layer contains a crosslinking agent. [4] The molding sheet according to any one of [1] to [3], wherein the average thickness of the non-impregnated portions is smaller than the average thickness of the nonwoven fabric. [5] The molding sheet according to any one of [1] to [4], wherein the average thickness of the non-impregnated portions is greater than the average thickness of the impregnated portions.

[0008] The present invention also includes a molded product obtained by molding any one of the molding sheets [6] and [1] to [5]. [Effects of the Invention]

[0009] According to the present invention, the above-mentioned configuration makes it possible to provide a molding sheet that can be easily used for various purposes. Furthermore, by molding using the molding sheet, various molded products can be obtained. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of a molding sheet according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in more detail below based on the following embodiments, but the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the above and below-described aims, and all such modifications are included within the technical scope of the present invention. Note that the dimensions of various components in the drawings may differ from the actual dimensions, as priority is given to helping understand the features of the present invention.

[0012] The molding sheet of the present invention comprises a nonwoven fabric and a resin layer laminated on the nonwoven fabric, wherein the nonwoven fabric has a breaking elongation of 100% or more at 130°C and a stress at 5% elongation of 10 N / 5 cm or more, and the resin layer contains a resin having a number average molecular weight of 5,000 or more and 150,000 or less, and is characterized by comprising an impregnated portion in which the nonwoven fabric is impregnated and a non-impregnated portion in which the nonwoven fabric is not impregnated.

[0013] The inventors have discovered that the above-described configuration makes it easier to prevent damage to the nonwoven fabric and resin layer of the molding sheet during molding processing. Furthermore, a molded body molded using a molding sheet having the above-described configuration is more likely to exhibit various properties, such as moisture resistance, waterproofing, and durability, due to the inclusion of a resin layer. Furthermore, by incorporating a filler having properties such as electromagnetic wave shielding and sound absorption into the resin layer, these properties can also be imparted to the molded body. In other words, a molding sheet having the above-described configuration is easily usable for a variety of applications. Below, a molding sheet according to an embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a cross-sectional view of a molding sheet according to an embodiment of the present invention.

[0014] As shown in Figure 1, a molding sheet 10 according to an embodiment of the present invention comprises a nonwoven fabric 1 and a resin layer 2 laminated on the nonwoven fabric 1. More specifically, the resin layer 2 is laminated on the nonwoven fabric 1 in a state in which the resin layer 2 is partially impregnated into the nonwoven fabric 1. In other words, the resin layer 2 comprises an impregnated portion 3 that is impregnated into the nonwoven fabric 1. Because the resin layer 2 comprises the impregnated portion 3, the resin layer 2 is less likely to peel off from the nonwoven fabric 1.

[0015] The average thickness of the impregnated portion 3 is preferably 5 μm or more, more preferably 10 μm or more. On the other hand, the upper limit of the average thickness of the impregnated portion 3 is not particularly limited, but may be, for example, 100 μm or less, 80 μm or less, or 70 μm or less.

[0016] Furthermore, the resin layer 2 has a non-impregnated portion 4 that is not impregnated into the nonwoven fabric 1. By providing the non-impregnated portion 4, the resin layer 2 becomes less likely to be damaged during molding.

[0017] The average thickness of the non-impregnated portion 4 is preferably 5 μm or more, more preferably 10 μm or more. On the other hand, the upper limit of the average thickness of the non-impregnated portion 4 is not particularly limited, but may be, for example, 130 μm or less, 80 μm or less, or 70 μm or less.

[0018] The average thickness of the non-impregnated portions 4 can be measured, for example, by the following method. First, three points are selected and marked in a 10 mm square area on the surface 4s of the non-impregnated portions 4 of the forming sheet 10, and the forming sheet 10 is frozen with liquid nitrogen. Next, the forming sheet 10 is cut in the thickness direction T so that each point can be observed. Each cross section is then observed at 2x magnification using a stereomicroscope, and on the image, a straight line is drawn in the thickness direction T from one of the three points (point A) on the surface 4s of the non-impregnated portions 4. The distance (μm) between point A and the intersection (point B) of the line and the surface 1s of the nonwoven fabric 1 is measured, and the average value is taken as the average thickness (μm) of the non-impregnated portions 4.

[0019] The average thickness of the impregnated portion 3 can be determined, for example, by measuring the distance (μm) between the intersection (point C) of the line in the thickness direction T and the impregnated surface 3s of the impregnated portion 3 and point B on the surface 1s of the nonwoven fabric 1 in the image of each cross section, and averaging the distances to obtain the average thickness (μm) of the impregnated portion 3. In this case, the impregnated surface 3s means the surface of the impregnated portion 3 opposite to the surface 1s of the nonwoven fabric 1.

[0020] In Fig. 1, the resin layer 2 is laminated on one side of the nonwoven fabric 1, but it may be laminated on both sides of the nonwoven fabric 1. It is preferable that the resin layer 2 is laminated on one side of the nonwoven fabric 1, as this allows for weight reduction.

[0021] Nonwoven fabric 1 has a breaking elongation of 100% or more at 130°C and a stress at 5% elongation of 10 N / 5 cm or more. When nonwoven fabric 1 has a breaking elongation of 100% or more at 130°C and a stress at 5% elongation of 10 N / 5 cm or more, the rigidity of nonwoven fabric 1 is improved, thereby improving the shape retention of the molded product. The breaking elongation at 130°C is preferably 120% or more. The elongation is expressed as a percentage of the elongation relative to the initial length, that is, it can be calculated by {(length after elongation - initial length) / initial length} x 100. For example, when a 100 mm long piece is stretched to 250 mm, the elongation is 150%. The stress at 5% elongation is preferably 12 N / 5 cm or more, more preferably 14 N / 5 cm or more.

[0022] Nonwoven fabrics 1 having a breaking elongation of 100% or more at 130°C and a stress at 5% elongation of 10 N / 5 cm or more can be made from a variety of materials. When a long-fiber nonwoven fabric is used, the above values can be achieved by the long-fiber nonwoven fabric preferably containing fibers having a birefringence (Δn) of 0.005 or more and 0.050 or less. When the birefringence (Δn) of the fibers is 0.005 or more, the rigidity of the long-fiber nonwoven fabric is improved, which facilitates improving the shape retention of the molded article. The birefringence (Δn) is preferably 0.007 or more, more preferably 0.008 or more. On the other hand, when the birefringence (Δn) is 0.050 or less, it facilitates improving processability. The birefringence (Δn) is preferably 0.020 or less, more preferably 0.015 or less. Specifically, the birefringence (Δn) can be measured by the method described in the Examples below.

[0023] In 100% by mass of the long-fiber nonwoven fabric, the content of fibers having a birefringence Δn of 0.005 or more and 0.050 or less is preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, still more preferably 95% by mass or more, particularly preferably 98% by mass or more, and most preferably 100% by mass.

[0024] The fibers contained in the long-fiber nonwoven fabric are preferably polyester fibers, more preferably thermoplastic polyester fibers, such as fibers containing polyethylene terephthalate as the main component and an organic compound with a glass transition temperature higher than that of polyethylene terephthalate (hereinafter sometimes referred to as a high Tg organic compound).

[0025] Polyethylene terephthalate is excellent in mechanical strength, heat resistance, shape retention, etc. To effectively exert these effects, the content of polyethylene terephthalate in the polyester fiber is preferably 90% by mass or more, more preferably 93% by mass or more, and even more preferably 94% by mass or more, when the polyester fiber is taken as 100% by mass. On the other hand, taking into account the content of high Tg organic compounds, the content of polyethylene terephthalate is preferably 99.8% by mass or less, more preferably 99.5% by mass or less, and even more preferably 98% by mass or less. The polyester fiber may contain polyesters other than polyethylene terephthalate, such as polytrimethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate.

[0026] The intrinsic viscosity of polyethylene terephthalate is preferably 0.3 dL / g or more and 0.9 dL / g or less. By making the intrinsic viscosity of polyethylene terephthalate 0.3 dL / g or more, thermal degradation is resistant and the durability of nonwoven fabric 1 can be improved. Therefore, the intrinsic viscosity of polyethylene terephthalate is more preferably 0.4 dL / g or more, even more preferably 0.5 dL / g or more, and even more preferably 0.55 dL / g or more. On the other hand, if the intrinsic viscosity of polyethylene terephthalate is 0.9 dL / g or less, stress during thermoforming of nonwoven fabric 1 can be easily reduced. Therefore, the intrinsic viscosity of polyethylene terephthalate is more preferably 0.7 dL / g or less. The intrinsic viscosity can be determined, for example, by weighing 0.1 g of polyethylene terephthalate resin, dissolving it in 25 ml of a mixed solvent of phenol / tetrachloroethane (60 / 40 (by weight)), measuring the viscosity three times at 30°C using an Ostwald viscometer, and calculating the average value.

[0027] Examples of high-Tg organic compounds include polystyrene and polystyrene-based copolymers. The polystyrene-based copolymer is preferably a thermoplastic polystyrene-based copolymer. The glass transition temperature of the polystyrene-based copolymer is preferably 100°C or higher and 160°C or lower. The polystyrene-based copolymer is preferably incompatible with polyethylene terephthalate. Because the polystyrene-based copolymer has a higher glass transition temperature than polyethylene terephthalate, the styrene-based copolymer solidifies first during cooling after melt spinning, inhibiting orientation and disrupting crystallinity. This facilitates improving the breaking elongation of the resulting long-fiber nonwoven fabric and further reducing the stress during elongation. Therefore, the glass transition temperature of the polystyrene-based copolymer is preferably 100°C or higher, more preferably 110°C or higher, and even more preferably 120°C or higher. Considering spinning productivity, the glass transition temperature is preferably 160°C or lower, more preferably 150°C or lower. The glass transition temperature can be determined by measuring at a heating rate of 20°C / min according to JIS K7122 (1987).

[0028] The polystyrene copolymer is preferably at least one selected from the group consisting of styrene-conjugated diene block copolymers, acrylonitrile-styrene copolymers, acrylonitrile-butadiene-styrene copolymers, styrene-acrylic acid ester copolymers, and styrene-methacrylic acid ester copolymers. Among these, at least one selected from the group consisting of styrene-acrylic acid ester copolymers and styrene-methacrylic acid ester copolymers is more preferred, with styrene-methacrylic acid ester copolymers being even more preferred. Examples of styrene-methacrylic acid ester copolymers include styrene-methyl methacrylate-maleic anhydride copolymers. These may be used alone or in combination. Commercially available products include PLEXIGLAS HW55 from Rohm GmbH & Co. KG, which can exhibit excellent effects even with a small amount added.

[0029] The content of the high Tg organic compound in the polyester fiber is preferably 0.02% by mass or more and 8% by mass or less, when the polyester fiber is taken as 100% by mass. By setting the content to 0.02% by mass or more, the above-mentioned effects of addition are more easily obtained. Therefore, the content of the high Tg organic compound is more preferably 0.05% by mass or more, even more preferably 0.2% by mass or more, even more preferably 2% by mass or more, and particularly preferably 4% by mass or more. On the other hand, by setting the content of the high Tg organic compound to 8% by mass or less, the difference in stretchability between polyethylene terephthalate and the high Tg organic compound can be reduced, making the fiber less likely to break. Therefore, the content of the high Tg organic compound is more preferably 8% by mass or less, even more preferably 7% by mass or less, and even more preferably 6% by mass or less.

[0030] The fiber diameter of the fibers contained in the long-fiber nonwoven fabric is preferably 5 μm or more. By making the fiber diameter 5 μm or more, the shape retention of the molded article can be improved. Therefore, the fiber diameter is preferably 5 μm or more, more preferably 7 μm or more, and even more preferably 12 μm or more. On the other hand, the upper limit of the fiber diameter is not particularly limited, but may be, for example, 80 μm or less, 60 μm or less, or 50 μm or less.

[0031] The long-fiber nonwoven fabric is preferably one in which the fibers have not been subjected to an entanglement treatment, which makes it easier to mold. The long-fiber nonwoven fabric is preferably a spunbonded or meltblown nonwoven fabric, and more preferably a spunbonded nonwoven fabric.

[0032] When a staple fiber nonwoven fabric having a breaking elongation of 100% or more at 130°C and a stress of 10 N / 5 cm or more at 5% elongation is used as nonwoven fabric 1, the above numerical values can be achieved by preferably containing a mixture of thermoplastic resin composite staple fibers having mechanical crimps and thermoplastic resin staple fibers having three-dimensional crimps or mechanical crimps made of a single component in the staple fiber nonwoven fabric.

[0033] The fineness of the thermoplastic resin conjugate short fiber is preferably 2 dtex or more and 6 dtex or less, and more preferably 3 dtex or more and 5 dtex or less. If the fineness of the thermoplastic resin conjugate short fiber is less than 2 dtex, the number of fibers constituting the nonwoven fabric will be large, resulting in many adhesion points between fibers in the nonwoven fabric, which will hinder fiber movement during molding, resulting in poor conformability to the molding die and the risk of tearing. Furthermore, if the fineness exceeds 6 dtex, the structure of the resulting short fiber nonwoven fabric will be coarse, making it difficult to control the resin impregnation. The fiber length of the thermoplastic resin conjugate short fiber is preferably 30 mm or more and 110 mm or less.

[0034] The thermoplastic resin composite short fiber preferably has mechanical crimp. Having mechanical crimp means that the main crimp form of the fiber is mechanical crimp, and does not exclude crimps that are used in combination with three-dimensional crimp.

[0035] Thermoplastic resin bicomponent staple fibers are bicomponent staple fibers formed from two or more resins with different melting points. Examples of composite fiber configurations include sheath-core bicomponent fibers and side-by-side bicomponent fibers. In the case of sheath-core bicomponent fibers, a thermoplastic resin with a lower melting point for the sheath component than for the core component is used. Examples of thermoplastic resins with higher melting points include polyester resin, nylon resin, and polypropylene. Examples of thermoplastic resins with lower melting points include modified low-melting-point polyester resin, polypropylene resin, and polyethylene resin. Among these, sheath-core bicomponent staple fibers using a low-melting-point modified polyester resin for the sheath component and polyethylene terephthalate for the core component are preferred. The mass ratio of the sheath component to the core component is preferably in the range of 60 / 40 to 40 / 60.

[0036] The thermoplastic resin staple fibers preferably have a fineness of 1 dtex or more and 17 dtex or less. Taking into consideration rigidity, elongation, and resin impregnation, it is more preferable to mix single-component thermoplastic resin staple fibers having a fineness of 3 dtex or more and 17 dtex or less and having three-dimensional crimps with hollow fiber cross-sectional shapes, with single-component thermoplastic resin staple fibers having a fineness of 1 dtex or more and 3 dtex or less and having mechanical crimps.

[0037] The thermoplastic resin staple fibers having a single component fineness of 3 dtex to 17 dtex and a three-dimensional crimp with a hollow cross-sectional shape are preferably 4 dtex to 15 dtex, more preferably 5 dtex to 13 dtex. If the fineness is less than 3 dtex, the crimp recovery stress of the nonwoven fabric decreases during heat treatment for molding, and the fabric may not be able to conform to the deep-draw shape of the molding die, resulting in tears or holes. If the fineness exceeds 17 dtex, the structure of the resulting reinforcing nonwoven fabric becomes coarse, making it difficult to control the resin impregnation. The fiber length is preferably 30 mm to 110 mm. The fiber cross-sectional shape is hollow. The use of hollow cross-sectional fibers imparts rigidity to the nonwoven fabric, improving its ability to conform to the molding die and reducing the occurrence of tears.

[0038] As for the single-component thermoplastic resin staple fiber having mechanical crimp and a fineness of 1 dtex to 3 dtex, 1.5 dtex to 2.5 dtex is preferred. If the fineness is less than 1 dtex, the number of fibers constituting the nonwoven fabric is large, resulting in many adhesion points between fibers in the nonwoven fabric, which inhibits fiber movement during molding, reduces conformability to the molding die, potentially leading to tearing and making it difficult to control resin impregnation. Furthermore, if the fineness exceeds 3 tex, the structure of the resulting nonwoven fabric becomes coarse, making it difficult to control resin impregnation. The fiber length is preferably 30 mm to 110 mm.

[0039] Examples of thermoplastic resins used for the thermoplastic resin short fibers include polyester resin, nylon resin, polypropylene, polyethylene, etc. Among these, polyethylene terephthalate is preferred.

[0040] The blending ratio of thermoplastic resin composite short fibers and single-component thermoplastic resin composite short fibers having 3D or mechanical crimps can be determined as appropriate, but if the content of thermoplastic resin composite short fibers is too high, the number of bonding points increases upon heat treatment, inhibiting fiber movement during molding, reducing mold conformability and risk of tearing. On the other hand, if the content of thermoplastic resin composite short fibers is too low, mold retention and rigidity may be insufficient. For these reasons, the blending ratio of thermoplastic resin composite short fibers is preferably 10% by mass or more and 50% by mass or less, more preferably 20% by mass or more and 40% by mass or less.

[0041] The short fiber nonwoven fabric can be produced, for example, by the following method. Thermoplastic resin composite staple fibers and single-component thermoplastic resin staple fibers having three-dimensional or mechanical crimps are mixed, and the mixed staple fibers are cross-layered and spread using two card spinning machines to obtain a web. The resulting web is entangled on one side using a first needle punch machine. The fibers are then mechanically entangled from above and below using second and third needle punch machines to further entangle the fibers, forming an integrated laminate and imparting the desired mechanical strength. The resulting staple fiber nonwoven fabric can be produced by melt-bonding the low-melting point component of the thermoplastic resin composite staple fibers using a heat treatment roll or air-through dryer. It is preferable to perform each of the above steps as a continuous, integrated manufacturing process to increase productivity. Furthermore, treatment with a heat treatment roll is more preferable to impart surface smoothness. Entanglement may also be performed using a water punch rather than a needle punch. Heat treatment may be performed on one or both sides using an air-through or calender.

[0042] The basis weight of the nonwoven fabric may be adjusted taking into consideration the rigidity after molding, and is not particularly limited, but is preferably 20 g / m 2 More than 500g / m 2 It is preferable that the basis weight is 20 g / m or less. 2 If the weight is more than this, the fabric will be less likely to break during molding. Therefore, the weight is more preferably 80 g / m 2 More preferably, 150 g / m 2 On the other hand, the basis weight is 500g / m 2If it is less than this, it will be easy to stretch during molding. Therefore, the basis weight is more preferably 400 g / m 2 More preferably, 300 g / m or less 2 The following is the result.

[0043] The breaking elongation and stress at 5% elongation of nonwoven fabric 1 at 130°C can be measured, for example, by the following method. For the breaking elongation at 130°C, five specimens measuring 5 cm wide and 20 cm long are cut from nonwoven fabric 1 in both the longitudinal and transverse directions. The specimens are then set with a chuck distance of 5 cm and placed in a furnace heated to 130°C. After one minute, they are deformed in the furnace at a tension rate of 10 cm / min using a universal tensile tester manufactured by Orientec Co., Ltd. to obtain a strain-stress curve. The elongation at break is read from the strain-stress curve, and the average value of five specimens in each of the longitudinal and transverse directions is used as the elongation (breaking elongation). For the stress at 5% elongation, five specimens measuring 5 cm wide and 20 cm long are cut from nonwoven fabric 1 in both the longitudinal and transverse directions. Next, the sample is set with a chuck distance of 5 cm and deformed at a tensile speed of 10 cm / min using a universal tensile tester manufactured by Orientec Co., Ltd. in an environment of 20°C to obtain a strain-stress curve. From the strain-stress curve, the stress at 5% elongation is read, and the average value of five points in each of the longitudinal and transverse directions is taken as the stress at 5% elongation.

[0044] When producing a long-fiber nonwoven fabric, reference can be made to the manufacturing methods described in JP 2017-222950 A and JP 2017-222951 A. When producing a short-fiber nonwoven fabric, reference can be made to the manufacturing method described in JP 2019-028060 A.

[0045] The resin layer 2 laminated on the nonwoven fabric 1 contains a resin (hereinafter sometimes simply referred to as resin A) having a number-average molecular weight of 5,000 or more and 150,000 or less. A number-average molecular weight of 5,000 or more facilitates improved toughness of the resin layer 2, allowing the resin to more easily adapt to deformation during molding. The number-average molecular weight is preferably 10,000 or more, more preferably 20,000 or more. On the other hand, a number-average molecular weight of 150,000 or less facilitates application when mixing the resin with a solvent and applying it to the nonwoven fabric 1 to form the resin layer 2, as this facilitates reducing the viscosity of the solution. Furthermore, even when the resin layer 2 is formed by heating and melting the resin to adhere it to the nonwoven fabric 1, this facilitates reducing the viscosity of the resin in its molten state, allowing the resin to more easily penetrate into the nonwoven fabric 1. As a result, the adhesive strength of the resin layer 2 to the nonwoven fabric 1 is improved, making the resin layer 2 less likely to peel during molding. The number average molecular weight can be determined in terms of polystyrene using, for example, a gel permeation chromatography (GPC) device.

[0046] In 100% by mass of the resin layer, the content of resin A is preferably 60% by mass or more, more preferably 75% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and particularly preferably 98% by mass or more.

[0047] The resin A is preferably a thermoplastic resin, more preferably an amorphous thermoplastic resin, which facilitates heat molding of the molding sheet 10. Specifically, the resin A is preferably at least one selected from the group consisting of polyester resins, polyester urethane resins, polyamide resins, polyamideimide resins, phenoxy resins, olefin resins, and acrylic resins, more preferably a polyester resin.

[0048] Polyester resins are formed mainly by reacting a carboxylic acid component with a hydroxyl group component. Examples of the carboxylic acid component include terephthalic acid, isophthalic acid, adipic acid, azelaic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, dimer acid, hydrogenated dimer acid, and naphthalenedicarboxylic acid. These may be used alone or in combination of two or more. Examples of the hydroxyl group component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, and the like. Examples of suitable hydroxyl groups include hexanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, dipropylene glycol, diethylene glycol, neopentyl glycol, 2,2,4-trimethyl-1,3-pentanediol, tricyclodecane dimethanol, neopentyl glycol hydroxypivalic acid ester, 1,9-nonanediol, 2-methyloctanediol, 1,10-dodecanediol, 2-butyl-2-ethyl-1,3-propanediol, polytetramethylene glycol, polyoxymethylene glycol, and cyclohexane dimethanol. These may be used alone or in combination of two or more.

[0049] Examples of polyester urethane resins include those obtained by addition polymerization of polyester polyols and polyisocyanates, such as those obtained by condensation reaction of polybasic acids such as dipic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, phthalic acid, and succinic acid with polyhydric alcohols such as propylene glycol, ethylene glycol, tetramethylene glycol, butanediol, hexanediol, and neopentyl glycol. Examples of polyisocyanates include aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate (MDI), tolylene diisocyanate (TDI), and xylylene diisocyanate (XDI); aliphatic diisocyanates such as hexamethylene diisocyanate (HDI) and lysine methyl ester diisocyanate (LDI); and alicyclic diisocyanates such as dicyclohexylmethane diisocyanate (HMDI) and isophorone diisocyanate (IPDI). These may be used alone or in combination of two or more.

[0050] Polyamide resins are polymers having amide bonds in the molecule. Examples of polyamide resins include nylon 6,6, nylon 6,9, nylon 6,10, nylon 6,12, nylon 6, nylon 12, nylon 11, and nylon 4,6. These may be used alone or in combination of two or more.

[0051] Polyamide-imide resins are polymers containing amide bonds and imide bonds, and examples of polyamide-imide resins include those obtained by reacting an acid component with a diamine.

[0052] Examples of the acid component include trimellitic acid, its anhydrides, and chlorides; tetracarboxylic acids such as pyromellitic acid, biphenyltetracarboxylic acid, biphenylsulfonetetracarboxylic acid, benzophenonetetracarboxylic acid, biphenylethertetracarboxylic acid, ethylene glycol bistrimellitate, and propylene glycol bistrimellitate, and their anhydrides; aliphatic dicarboxylic acids such as oxalic acid, adipic acid, malonic acid, sebacic acid, azelaic acid, dodecanedicarboxylic acid, dicarboxypolybutadiene, dicarboxypoly(acrylonitrile-butadiene), and dicarboxypoly(styrene-butadiene); alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 4,4'-dicyclohexylmethanedicarboxylic acid, and dimer acid; and aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, diphenylsulfonedicarboxylic acid, diphenyletherdicarboxylic acid, and naphthalenedicarboxylic acid. These may be used alone or in combination of two or more.

[0053] Examples of diamines include aliphatic diamines such as ethylenediamine, propylenediamine, and hexamethylenediamine, and diisocyanates thereof; alicyclic diamines such as 1,4-cyclohexanediamine, 1,3-cyclohexanediamine, isophoronediamine, and 4,4'-dicyclohexylmethanediamine, and diisocyanates thereof; aromatic diamines such as m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, benzidine, o-tolidine, 2,4-tolylenediamine, 2,6-tolylenediamine, and xylylenediamine, and diisocyanates thereof; etc. These may be used alone or in combination of two or more.

[0054] Examples of phenoxy resins include resins obtained by reacting epihalohydrin with a dihydric phenol compound, and resins obtained by reacting a divalent epoxy compound with a dihydric phenol compound. Specific examples include bisphenol-type phenoxy resins such as bisphenol A-type phenoxy resin, bisphenol F-type phenoxy resin, bisphenol S-type phenoxy resin, bisphenol M-type phenoxy resin, bisphenol P-type phenoxy resin, bisphenol Z-type phenoxy resin, and phenoxy resins having two or more bisphenol skeletons, novolac-type phenoxy resin, and naphthalene-type phenoxy resin. These may be used alone or in combination of two or more.

[0055] Examples of the olefin-based resin include homopolymers or copolymers of olefins such as ethylene, propylene, and butene; copolymers of these olefins with copolymerizable monomer components; and maleic anhydride-modified versions of these. Examples of the olefin-based resin include at least one selected from the group consisting of polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-α-olefin copolymer, ethylene-propylene copolymer, ethylene-butene copolymer, and propylene-butene copolymer.

[0056] Examples of acrylic resins include those obtained by polymerizing or copolymerizing (meth)acrylic monomers such as (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, (meth)acrylamide, (meth)acrylonitrile, and glycidyl (meth)acrylate. These may be used alone or in combination of two or more.

[0057] In addition to resin A, resin layer 2 may contain crosslinking agents such as blocked isocyanates, flame retardants such as antimony oxide, aluminum hydroxide, magnesium hydroxide, plasticizers such as phthalates and adipates, hydrolysis inhibitors such as carbodiimides, electromagnetic wave shielding fillers such as aluminum, zinc, iron, silver, copper, and zinc oxide, sound absorbing fillers such as silica, etc. These additives may be used alone or in combination of two or more.

[0058] It is preferable that the molding sheet 10 does not have any broken portions in the resin layer 2 and nonwoven fabric 1 after the following molding process in accordance with JIS 1096 (2010) 8.18.2B method. <Molding processing conditions> The molding sheet 10 is cut into a circle with a diameter of 72 mm. Next, a convex mold is prepared, which includes a cylindrical portion with a diameter of 25 mm and a hemispherical portion with a radius of 12.5 mm at the tip of the cylindrical portion, and a concave mold capable of fitting into the hemispherical portion. The molding sheet 10 is then placed on the concave mold with the resin layer 2 facing the concave mold, and a ring-shaped presser plate is placed around the periphery of the molding sheet 10. The molding sheet is then heated at a temperature of 140°C for 1 minute. The hemispherical and cylindrical portions are then pressed 20 mm vertically into the molding sheet 10 at a speed of 20 mm / min, maintained for 30 seconds, and then released from the mold. The molded product is then cooled with cold air from a hair dryer for 1 minute, after which it is removed.

[0059] The molding sheet preferably has a peel strength of the resin layer 2 of 2 N / cm or more. This makes the resin layer 2 less likely to break during molding. Therefore, the peel strength of the resin layer 2 is more preferably 3 N / cm or more, and even more preferably 4 N / cm or more. On the other hand, there is no particular upper limit, but it may be, for example, 15 N / cm or less, or 10 N / cm or less. The peel strength of the resin layer 2 can be measured by the method described in the examples below.

[0060] The resin layer 2 can be formed on the nonwoven fabric 1 by a transfer method, a screen printing method, etc. When performing the transfer method, the resin may be heated and melted, or a solvent such as methyl ethyl ketone may be mixed with the resin.

[0061] The present invention also includes a molded body obtained by molding the molding sheet 10. In molding, the molding sheet 10 may be subjected to drawing such as shallow drawing or deep drawing under heating conditions of, for example, 100 to 180°C. Furthermore, the shape of the processed shape is not limited, and it is possible to perform cylindrical drawing, square cylinder drawing, conical drawing, pyramidal drawing, spherical head drawing, other irregular shape drawing, and the like. [Example]

[0062] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples, and modifications can be made within the scope of the above and below-described aims, and all such modifications are included in the technical scope of the present invention.

[0063] Birefringence (Δn): Ten randomly selected points on the nonwoven fabric were used to extract single fibers, and the fiber diameter and retardation were measured using a Nikon OPTIPHOT-POL polarizing microscope to determine the birefringence (Δn).

[0064] Thickness of nonwoven fabric: The thickness of the nonwoven fabric was measured based on 6.1 of JIS L 1913 (2010).

[0065] Basis weight of nonwoven fabric: The basis weight of the nonwoven fabric was determined based on "mass per unit area" in 6.2 of JIS L 1913 (2010).

[0066] Average thickness of non-impregnated portion: Three points were selected and marked in a 10 mm square area on the surface of the non-impregnated portion of the molding sheet, and the molding sheet was frozen with liquid nitrogen. The molding sheet was then cut in the thickness direction so that each point could be observed. Each cross section was then observed at 2x magnification using a LEICA stereomicroscope, and a straight line was drawn in the thickness direction from one of the three points (point A) on the surface of the non-impregnated portion in the image. The distance (μm) between point A and the intersection (point B) of the line and the surface of the nonwoven fabric was measured, and the average value was taken as the average thickness (μm) of the non-impregnated portion.

[0067] Average thickness of the impregnated portion: In each of the cross-sectional images, the distance (μm) between the intersection (point C) of the line in the thickness direction and the impregnated surface of the impregnated portion and point B on the surface of the nonwoven fabric was measured, and the average value was taken as the average thickness (μm) of the impregnated portion.

[0068] Number average molecular weight of resin: A chromatogram was measured using a gel permeation chromatography (GPC) device manufactured by Shimadzu Corporation, and the number average molecular weight (Mn) of the resin was determined based on a calibration curve using standard polystyrene.

[0069] Peel strength: The molding sheet was cut into a length of 100 mm and a width of 250 mm. Then, a 20 mm wide, 25 μm thick hot melt tape manufactured by Sun Chemical Co., Ltd. was thermocompressed onto the resin layer of the molding sheet using an iron heated to a surface temperature of 120°C. Then, using an autograph tensile tester manufactured by Shimadzu Corporation, the hot melt tape was peeled off together with the resin layer at an autograph speed of 300 mm / min, a peel distance of 50 mm, and a peel angle of 180°. This measurement was repeated twice, and the average value was taken as the peel strength (N / cm). The value was rounded to the nearest whole number.

[0070] Moldability evaluation: The moldability of the moldable sheet was evaluated by the following molding process according to JIS 1096 (2010) 8.18.2B method. When the surface was observed during molding, if there was damage in at least one of the resin layer and the nonwoven fabric, it was marked with ×, and if there was no damage in the resin layer or the nonwoven fabric, it was marked with ○. <Molding processing conditions> The molding sheet was cut into a circle with a diameter of 72 mm. Next, a convex mold having a cylindrical portion with a diameter of 25 mm and a hemispherical portion with a radius of 12.5 mm at the tip of the cylindrical portion, and a concave mold capable of fitting into the hemispherical portion were prepared. Next, the molding sheet was placed on the concave mold with the resin layer side facing the concave mold, and a ring-shaped presser plate was placed on the periphery of the molding sheet. Next, it was heated at a heating temperature of 140 ° C for a heating time of 1 minute, and then the hemispherical portion and cylindrical portion were pressed 20 mm vertically into the molding sheet at a speed of 20 mm / min, and then maintained for 30 seconds before being demolded. After that, it was cooled with cold air from a dryer for 1 minute, and the molded body was removed.

[0071] Example 1 Using spunbond spinning equipment, a resin containing polyethylene terephthalate (hereinafter referred to as "PET") with an intrinsic viscosity of 0.63 dl / g and 0.40 mass% of styrene-methyl methacrylate-maleic anhydride copolymer (PLEXIGLAS HW55 (hereinafter referred to as "HW55") manufactured by Rohm GmbH & Co. KG) with a glass transition temperature of 122°C was added. The resin was spun from a spinneret with an orifice diameter of 0.23 mm at a single-hole output rate of 0.75 g / min. Furthermore, a pressure of 0.6 kg / cm was applied to the ejector. 2 Dry air was supplied at a pressure (jet pressure) of 1000 kJ / min, and the fibers were drawn in one step, spreading them onto a conveyor below and collected to obtain a long-fiber fleece. The obtained long-fiber fleece had a fiber diameter of 22.0 μm, a birefringence Δn of 0.0120, and a converted spinning speed of 1430 m / min.

[0072] The obtained long fiber fleece was pre-heat-pressed using a pair of pre-heat-pressing rolls consisting of two flat rolls, each with a surface temperature of 80°C and a pressing pressure of 8 kN / m, and then pre-pressed at a roll surface temperature of 145°C and a pressing pressure of 3.0 kgf / cm. 2 The final compression bonding was carried out while the surface was restrained by a felt calender under the conditions of a processing time of 9.3 seconds and a processing speed of 8.4 m / min, to obtain a spunbonded nonwoven fabric. The nonwoven fabric had a basis weight of 210 g / m 2 , and the thickness was 650 μm.

[0073] Next, the following resin and solvent were mixed in the following ratio, heated to 30°C, dissolved in a stirrer, and a crosslinking agent was added in the following ratio to obtain a coating material for the resin layer. Resin: Byron BX-1001 (manufactured by Toyobo Co., Ltd.) 100 parts Solvent: 200 parts methyl ethyl ketone Crosslinking agent: Blocked isocyanate 7960 (manufactured by Baxenden) 8 parts

[0074] The resin layer coating material was then applied to a release film, SP3000#75 (manufactured by Toyo Cross Co., Ltd.), at a rate of 450 g per square meter using a comma coater, and then dried in a dryer at 150°C for 3 minutes to obtain a resin layer with a release film.

[0075] Next, the resin layer side of the resin layer with release film was placed on the surface of the spunbond nonwoven fabric, and the fabric was laminated at 60°C and 20 N / cm 2 The resulting laminate with the release film was left to stand for 48 hours in a room heated to 60° C. Thereafter, the release film was peeled off to obtain a molding sheet.

[0076] Comparative Example 1 A laminate with a release film was obtained in the same manner as in Example 1, except that a polyester spunbond nonwoven fabric (Ekure (registered trademark) W6B61A) manufactured by Toyobo Co., Ltd. was used as the nonwoven fabric. After leaving it in a room heated to 60°C for 48 hours, the release film was peeled off to obtain a molding sheet. The basis weight of the nonwoven fabric was 210 g / m 2 The thickness was 650 μm. The birefringence Δn was 0.095.

[0077] Comparative Example 2 The following resin and solvent were mixed in the following proportions, heated to 30°C, dissolved in a stirrer, and a crosslinking agent was added in the following proportions to obtain a coating material for the resin layer. Resin: 100 parts of acrylic resin (commercially available) with a number average molecular weight equivalent to 180,000 Solvent: 150 parts methyl ethyl ketone, 50 parts dimethylformamide Crosslinking agent: Coronate L (manufactured by Nippon Polyurethane Industry Co., Ltd.) 8 parts

[0078] Next, using the same spunbond nonwoven fabric as in Example 1, a laminate with a release film was obtained in the same manner as in Example 1, and after leaving it in a room heated to 60°C for 48 hours, the release film was peeled off to obtain a molding sheet. These molding sheets were used for various evaluations. The results are shown in Table 1. The basis weight of the nonwoven fabric was 210 g / m 2 , and the thickness was 650 μm.

[0079] Example 2 The thermoplastic resin composite staple fibers were 45% by mass of mechanically crimped core-sheath composite staple fibers with a fineness of 4 dtex and a fiber length of 51 mm, consisting of a polyethylene terephthalate core (melting point 255°C) and a copolymer polyester sheath (melting point 110°C).The thermoplastic resin staple fibers were 30% by mass of hollow staple fibers with a fineness of 6 dtex and a fiber length of 51 mm, consisting of polyethylene terephthalate (melting point 255°C) that had been three-dimensionally crimped using an asymmetric cooling method, and 25% by mass of mechanically crimped polyethylene terephthalate (melting point 255°C).The thermoplastic resin composite staple fibers and the thermoplastic resin staple fibers were blended and carded to obtain a web, which was then punched using the first, second, and third needle punch machines, each with a penetration of 38 needles / cm. 2 Down thrust, 60 pieces / cm 2 Upward thrust, 60 pieces / cm 2 After entangling the fibers with a downward thrust, the fabric is heat-treated in an air-through dryer at 130°C, resulting in a fabric weight of 143 g / m 2 Next, a resin was laminated on the surface of the short fiber nonwoven fabric in the same manner as in Example 1 to obtain a molding sheet.

[0080] Comparative Example 3 The thermoplastic resin composite staple fibers were 100% by mass of mechanically crimped core-sheath composite staple fibers with a fineness of 4 dtex and a fiber length of 51 mm, the core component of which was polyethylene terephthalate (melting point 255°C) and the sheath component of copolymer polyester (melting point 110°C). After carding to obtain a web, the web was heat-treated in an air-through dryer at 130°C to obtain a weight of 143 g / m. 2 Next, a resin was laminated on the surface of the short fiber nonwoven fabric in the same manner as in Example 1 to obtain a molding sheet.

[0081] [Table 1]

[0082] The molding sheet of Example 1 could be molded without any damage occurring to the spunbond nonwoven fabric or resin layer when drawn with a push-in depth of 20 mm.

[0083] On the other hand, the molding sheet of Comparative Example 1 had a birefringence index Δn of the fibers of the spunbond nonwoven fabric outside the range of 0.005 to 0.050, and the spunbond nonwoven fabric broke when drawn with a press-in depth of 20 mm. Furthermore, when a similar drawing was performed with a press-in depth of 10 mm, it was found that the spunbond nonwoven fabric also broke at a press-in depth of 10 mm.

[0084] The molding sheet of Comparative Example 2 had a resin layer with a number average molecular weight exceeding the range of 5,000 to 150,000, and the resin layer peeled off and broke when drawn with a push-in depth of 20 mm. Furthermore, when a similar drawing was performed with a push-in depth of 10 mm, it was found that the resin layer peeled off and broke even with a push-in depth of 10 mm.

[0085] The molding sheet of Example 2 could be molded without any damage occurring to the short fiber nonwoven fabric or resin layer when drawn with a push-in depth of 20 mm.

[0086] In the molding sheet of Comparative Example 3, tears occurred in the short fiber nonwoven fabric during drawing with a push-in depth of 20 mm. [Explanation of symbols]

[0087] 1. Nonwoven fabric 1s Nonwoven surface 2 Resin layer 3 Impregnation part 3s Impregnated surface of the impregnated part 4 Non-impregnated area 4s Surface of non-impregnated area 10 Molded Sheet

Claims

1. a nonwoven fabric and a resin layer laminated on the nonwoven fabric, wherein the nonwoven fabric has a breaking elongation of 100% or more at 130°C and a stress at 5% elongation of 10 N / 5 cm or more, the resin layer contains a polyester-based resin having a number average molecular weight of 5,000 or more and 150,000 or less, and the content of the polyester-based resin in 100% by mass of the resin layer is 90% by mass or more, and the resin layer has an impregnated portion in which the nonwoven fabric is impregnated and a non-impregnated portion in which the nonwoven fabric is not impregnated, A molding sheet characterized in that no damaged portions occur in the resin layer and the nonwoven fabric after molding under the following molding processing conditions in accordance with JIS 1096 (2010) 8.18.2B method. <Molding processing conditions> The molding sheet was cut into a circle, and a convex mold having a cylindrical portion and a hemispherical portion with a radius of 12.5 mm provided at the tip of the cylindrical portion, and a concave mold capable of fitting into the hemispherical portion were prepared. The circular molding sheet was placed on the concave mold with the resin layer side facing the concave mold, and a ring-shaped pressure plate was placed on the peripheral edge of the molding sheet. The molding sheet was heated at a heating temperature of 140°C for a heating time of 1 minute, and then the hemispherical portion and the cylindrical portion were pressed 20 mm vertically into the molding sheet at a speed of 20 mm / min. This was maintained for 30 seconds, and then cooled with cold air for 1 minute before being removed.

2. The molding sheet according to claim 1 , wherein the resin layer contains a crosslinking agent.

3. 3. The molding sheet according to claim 1, wherein the average thickness of the non-impregnated portion is smaller than the average thickness of the nonwoven fabric.

4. 4. The molding sheet according to claim 1, wherein the average thickness of the non-impregnated portions is greater than the average thickness of the impregnated portions.

5. A molded article obtained by molding the molding sheet of any one of claims 1 to 4.

Images