Sheet-shaped molding material, molded body, and method for producing same

Abstract

To provide a molding material, etc. capable of manufacturing a molded body using lacquer which has a thinner thickness.SOLUTION: A manufacturing method of a sheet-like molding material includes the steps of: impregnating a sheet-like base material containing vegetable fibers with lacquer to obtain a lacquer-contained sheet-like base material; and heating the lacquer-contained sheet-like base material to obtain the sheet-like molding material.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a sheet-shaped molding material, a molded article, and a method for producing the same. [Background technology]

[0002] Lacquer is the sap that seeps out from the lacquer tree, and lacquerware coated with lacquer is used for tableware, furniture, crafts, etc. In recent years, synthetic resin products have come to be widely used instead of lacquerware, but some of these products are suspected of containing substances that are harmful to the human body.

[0003] Therefore, with the aim of expanding the uses of lacquer and providing products that are not likely to have adverse effects on the human body, Patent Document 1 discloses a method of forming a molded body by compression molding a powder material obtained from lacquer and plant fibers. Specifically, Patent Document 1 discloses "a method of mixing and kneading lacquer and plant fibers in a weight ratio of 1:9 to 6:4, heating with stirring at a temperature of 90 to 180°C for 30 to 120 minutes to partially thermally polymerize urushiol, pulverizing the product to obtain a compression moldable powder that is in a dry state at room temperature, and compression molding the powder in a mold of a predetermined shape at a temperature of 120 to 180°C and a pressure of 15 to 40 MPa to obtain a compression molded body of lacquer / plant fibers."

[0004] Furthermore, Patent Document 2 discloses a "powdered molding material obtained by three-dimensionally kneading lacquer and plant fibers while heating them" and a molded body obtained by compression molding the material, with the aim of improving the powder material and molded body of Patent Document 1. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 3779290 specification [Patent Document 2] Patent No. 6140607 specification Summary of the Invention [Problem to be solved by the invention]

[0006] When using powder materials such as those disclosed in Patent Documents 1 and 2, there is a problem in that it is difficult to produce a thin plate-shaped compression molded body of about 1 to 2 mm. Therefore, an object of the present invention is to provide a molding material etc. that can be used to produce a thin molded body using lacquer. [Means for solving the problem]

[0007] As a result of extensive research, the inventors discovered that the desired molding material could be obtained by impregnating a sheet-like substrate containing plant fibers with lacquer and then heating it, thus completing the present invention.

[0008] The present invention includes the following embodiments. [1] A step of impregnating a sheet-like substrate containing plant fibers with lacquer to obtain a lacquer-containing sheet-like substrate; A step of heating the lacquer-containing sheet-like substrate to obtain a sheet-like molding material; A method for producing a sheet-shaped molding material comprising the steps of: [2] The method according to [1], wherein the sheet-like substrate has a thickness of 0.1 to 2.0 mm. [3] The density of the sheet-like substrate is 0.10 to 0.85 g / cm 3 The method for producing a compound according to [1] or [2], [4] The method according to any one of [1] to [3], wherein the amount of the lacquer contained in the lacquer-containing sheet-like substrate is 30 to 70 mass % based on the mass of the lacquer-containing sheet-like substrate. [5] The method according to any one of [1] to [4], wherein the heating of the lacquer-containing sheet-like substrate partially hardens the lacquer contained in the lacquer-containing sheet-like substrate. [6] The method according to any one of [1] to [5], wherein the heating of the lacquer-containing sheet-like substrate is carried out at 90 to 180°C. [7] The method according to any one of [1] to [6], wherein the heating of the lacquer-containing sheet-like substrate is carried out for 30 to 360 minutes. [8] A step of compression molding a sheet-shaped molding material produced by the production method according to any one of [1] to [7]; A method for producing a molded body, comprising the steps of: [9] The method according to [8], wherein the compression molding is carried out at 120 to 180°C.

[10] The method according to [8] or [9], wherein the compression molding is carried out by stacking two or more sheets of the sheet-like molding material.

[11] A step of applying lacquer to the surface of the molded body; The method for producing a semiconductor device according to any one of [8] to

[10] , further comprising:

[12] A step of heating the molded body to completely harden the lacquer; The method for producing a semiconductor device according to any one of [8] to

[11] , further comprising:

[13] A sheet-like substrate containing plant fibers; Lacquer impregnated into the sheet-like substrate; Including, The lacquer is partially cured. Sheet-shaped molding material.

[14] The sheet-shaped molding material according to

[13] , wherein the sheet-shaped molding material consists only of the plant fibers and the lacquer.

[15] The sheet-shaped molding material according to

[13] or

[14] , wherein the thickness of the sheet-shaped molding material is 0.1 to 2.0 mm.

[16] A molded product which is a compression molded product of the sheet-form molding material according to any one of

[13] to

[15] .

[17] The molded body according to

[16] , wherein two or more sheets of the sheet-like molding material are laminated and compressed.

[18] The molded article according to

[16] or

[17] , wherein the thickness of the molded article is 0.1 mm or more. Effect of the Invention

[0009] According to the present invention, it is possible to provide a molding material etc. that can be used to manufacture a thin molded article using lacquer. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 shows the maximum stress of the molded bodies (filter paper thickness: 0.8 mm) of Examples 1 to 5 in which the amount of lacquer impregnation was changed, and of the comparative control. [Diagram 2] FIG. 2 shows the elastic modulus of the molded bodies (filter paper thickness: 0.8 mm) of Examples 1 to 5 and a comparative control, in which the amount of lacquer impregnation was changed. [Diagram 3] FIG. 3 shows the maximum stress of the molded bodies (filter paper thickness: 0.34 mm) of Examples 6 and 7, in which the heat treatment time after lacquer impregnation was changed, and the comparative control. [Figure 4] FIG. 4 shows the elastic modulus of the molded bodies (filter paper thickness: 0.34 mm) of Examples 6 and 7, in which the heat treatment time after impregnation with lacquer was changed, and of the comparative example. [Diagram 5] FIG. 5 shows the maximum stress of the molded bodies (filter paper thickness: 0.8 mm) of Examples 8 to 10 and a comparative control, in which the heat treatment time after lacquer impregnation was changed. [Figure 6] FIG. 6 shows the elastic modulus of the molded bodies (filter paper thickness: 0.8 mm) of Examples 8 to 10 and a comparative control, in which the heat treatment time after lacquer impregnation was changed. [Figure 7] FIG. 7 shows the maximum stress of the molded bodies (filter paper thickness: 1.2 mm) of Examples 11 and 12, in which the heat treatment time after impregnation with lacquer was changed, and the comparative example. [Figure 8] FIG. 8 shows the elastic modulus of the molded bodies (filter paper thickness: 1.2 mm) of Examples 11 and 12, in which the heat treatment time after impregnation with lacquer was changed, and of the comparative control. [Figure 9] FIG. 9 shows the maximum stress of the laminated molded bodies (filter paper thickness: 0.8 mm) of Examples 1A to 5A in which the amount of lacquer impregnation was changed. [Figure 10]FIG. 10 shows the elastic modulus of the laminated molded bodies (filter paper thickness: 0.8 mm) of Examples 1A to 5A in which the amount of lacquer impregnation was changed. [Figure 11] FIG. 11 shows the maximum stress of the laminated molded bodies (filter paper thickness: 0.8 mm) of Examples 8A and 9A in which the heat treatment time after lacquer impregnation was changed. [Figure 12] FIG. 12 shows the elastic modulus of the laminated molded bodies (filter paper thickness: 0.8 mm) of Examples 8A and 9A in which the heat treatment time after lacquer impregnation was changed. [Figure 13] FIG. 13 shows the maximum stress of the laminated molded bodies (filter paper thickness: 1.2 mm) of Examples 11A and 12A in which the heat treatment time after lacquer impregnation was changed. [Figure 14] FIG. 14 shows the elastic modulus of the laminated molded bodies (filter paper thickness: 1.2 mm) of Examples 11A and 12A in which the heat treatment time after lacquer impregnation was changed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments of the present invention will be described in detail, however, the present invention is not limited to these and various modifications are possible without departing from the gist of the present invention.

[0012] <Method of manufacturing sheet-shaped molding material> One embodiment of the present invention relates to a method for producing a sheet-like molding material, comprising a step of impregnating a sheet-like substrate containing plant fibers with lacquer to obtain a lacquer-containing sheet-like substrate (hereinafter referred to as the "impregnation step"), and a step of heating the lacquer-containing sheet-like substrate to obtain a sheet-like molding material (hereinafter referred to as the "heating step").

[0013] In the manufacturing method according to this embodiment, a molding material capable of manufacturing a thin molded body can be obtained by impregnating a sheet-like substrate with lacquer and heating it (hardening by thermal polymerization). In addition, by using the molding material, it is also possible to improve the durability of the molded body.

[0014] The reasons why a molded article having a small thickness and excellent durability can be produced are presumed to be as follows, but the present invention is not limited to these reasons in any way. In other words, in the powder material disclosed in Patent Document 1, the plant fibers are cut into short pieces during powderization, which reduces the entanglement of the plant fibers and reduces durability, whereas the plant fibers constituting the sheet-like substrate used in this embodiment have relatively long fiber lengths and tend to entangle with each other, so it is expected that durability can be maintained even when the thickness is reduced.

[0015] [Impregnation process] The impregnation step is a step of impregnating a sheet-like substrate containing plant fibers with lacquer to obtain a lacquer-containing sheet-like substrate. The method of impregnation with lacquer is not particularly limited, and examples thereof include a method of applying lacquer to a sheet-like substrate and a method of immersing a sheet-like substrate in lacquer.

[0016] The thickness of the sheet-like substrate is preferably 0.1 to 2.0 mm, more preferably 0.2 to 1.7 mm, and even more preferably 0.3 to 1.4 mm. By setting the thickness of the sheet-like substrate within the above range, the sheet-like substrate can be uniformly impregnated with lacquer.

[0017] The density of the sheet-like substrate is preferably 0.10 to 0.85 g / cm 3 and more preferably 0.25 to 0.70 g / cm 3 and more preferably 0.40 to 0.55 g / cm 3 By setting the density of the sheet-like substrate within the above range, the sheet-like substrate can be uniformly and sufficiently impregnated with lacquer.

[0018] The plant fibers constituting the sheet-like substrate are not particularly limited, but examples thereof include plant fibers derived from cedar, cypress, hemlock, paulownia, pine, spruce, bamboo, reed, cotton, etc. One type of plant fiber may be used alone, or two or more types may be used in combination. Although not particularly limited, the sheet-like substrate is preferably composed only of plant fibers, and more preferably composed only of cellulose.

[0019] The type of lacquer is not particularly limited, and examples thereof include lacquer obtained from Japanese lacquer trees, Chinese lacquer trees, Taiwanese lacquer trees, Vietnamese lacquer trees, Thai lacquer trees, and Myanmar lacquer trees. The main components of lacquer vary depending on the lacquer tree, and examples thereof include urushiol, laccol, and thitsiol. Any lacquer containing any of the main components can be used in the manufacturing method according to the present embodiment. One type of lacquer may be used alone, or two or more types may be used in combination.

[0020] The amount of lacquer contained in the lacquer-containing sheet-like substrate is preferably 30 to 70% by mass, more preferably 48 to 68% by mass, and even more preferably 58 to 68% by mass, based on the mass of the lacquer-containing sheet-like substrate. By making the amount of lacquer 30% by mass or more, the sheet-like substrate can be uniformly impregnated with the lacquer. By making the amount of lacquer 70% by mass or less, elution of the lacquer from the sheet-like substrate can be suppressed.

[0021] [Heating process] The heating step is a step in which the lacquer-containing sheet-like substrate is heated to obtain a sheet-like molding material. By heating the lacquer-containing sheet-like substrate, the laccase contained in the lacquer can be inactivated and the hardening of the lacquer due to heating (thermal polymerization) can be promoted. Laccase causes oxidative polymerization of the lacquer, but since the degree of oxidative polymerization is greatly affected by factors such as storage time, temperature, and humidity, as well as the composition of the lacquer, it is difficult to maintain stable quality if the laccase is active. By inactivating the laccase and using thermal polymerization instead, the quality can be stabilized.

[0022] The heating method is not particularly limited, and examples thereof include heating the lacquer-containing sheet-like substrate with a hot air dryer. Although the sheet-like molding material is dry to the touch at room temperature, it is preferable to heat the lacquer-containing sheet-like substrate to a degree that softens it under the conditions of the forming process described below.

[0023] In the heating step, it is preferable to partially harden the lacquer contained in the lacquer-containing sheet-like substrate. By partially hardening the lacquer (in other words, by partially unhardening the lacquer), the lacquer-containing sheet-like substrate is appropriately softened when compressed in the subsequent molding step, making it easier to perform molding. In addition, by partially hardening the lacquer, the hardening time in the molding step can be shortened. Furthermore, by partially unhardening the lacquer, when two or more sheets of sheet-like molding material are stacked and compressed in the following molding step, a molded body in which the sheet-like molding materials are bonded to each other and integrated can be obtained. Methods for confirming that the lacquer is partially hardened include, for example, a method of dissolving unhardened lacquer with acetone, or a method of observing a peak derived from the double bond of the main component of the lacquer by infrared spectroscopy.

[0024] The heating temperature is preferably 90 to 180° C., more preferably 100 to 160° C., and even more preferably 110 to 140° C. By setting the heating temperature to 90° C. or higher, the laccase can be sufficiently inactivated and the thermal polymerization can proceed sufficiently. By setting the heating temperature to 180° C. or lower, excessive thermal polymerization can be suppressed and ignition due to heat generation can be avoided.

[0025] The heating time may be adjusted as appropriate depending on, for example, the thickness of the sheet-like substrate and the amount of lacquer impregnated, For example, the heating time may be 30 to 360 minutes, 60 to 360 minutes, or 120 to 360 minutes.

[0026] <Method of manufacturing molded body> One embodiment of the present invention relates to a method for producing a molded body, which includes a step of compression molding the sheet-shaped molding material produced by the above-mentioned <Method for producing a sheet-shaped molding material> (hereinafter referred to as "molding step").

[0027] The method of compression molding is not particularly limited, and examples thereof include a method in which a sheet-shaped molding material is placed in a mold of a desired shape and compressed. Examples of the mold include a metal sheet mold and an embossing mold.

[0028] In the manufacturing method according to the present embodiment, a molded body having a small thickness can be manufactured by using a sheet-shaped molding material. In addition, the durability of the molded body can be improved by using the sheet-shaped molding material.

[0029] The compression molding temperature is preferably 120 to 180° C., more preferably 140 to 160° C. By setting the compression molding temperature to 120° C. or higher, it is possible to avoid insufficient curing and shorten the molding time. By setting the compression molding temperature to 180° C. or lower, it is possible to avoid a situation where the resin completely cures before being molded into a desired shape and also to avoid a situation where a part of the molded body expands due to gas generation.

[0030] The compression molding pressure may be appropriately adjusted depending on, for example, the thickness and shape of the molded body, For example, the compression molding pressure may be 1 to 20 MPa, 2 to 14 MPa, or 4 to 8 MPa.

[0031] In the molding step, one sheet-shaped molding material may be compression molded, or two or more sheets of the sheet-shaped molding material may be laminated and compression molded. A material different from the sheet-shaped molding material according to the present embodiment may be laminated with the sheet-shaped molding material (including a mode in which a different material is sandwiched between the sheet-shaped molding materials) and compression molded.

[0032] The manufacturing method of the molded body according to this embodiment may further include a step of applying lacquer to the surface of the molded body obtained in the molding step (hereinafter referred to as the "coating step"). Since the sheet-like molding material used to manufacture the molded body contains lacquer, the molded body has the property of being easily compatible with lacquer. Therefore, in the coating step, the surface treatment that is generally performed before applying lacquer can be omitted.

[0033] The method for producing a molded body according to this embodiment may further include a step of heating the molded body after the molding step or the coating step (hereinafter referred to as the "final heating step"). It is preferable that the lacquer contained in the molded body (including the lacquer coated on the surface of the molded body) is completely cured by the final heating step. This can improve, for example, the adhesion between the molded body surface and the lacquer coated on the surface, and can reduce the possibility of lacquer rash occurring when using the molded body.

[0034] <Sheet-shaped molding material> One embodiment of the present invention relates to a sheet-like molding material comprising a sheet-like substrate containing plant fibers and lacquer impregnated in the sheet-like substrate, the lacquer being partially cured. Details of the sheet-like substrate and the lacquer are as described above in the <Production method of sheet-like molding material>.

[0035] The sheet-shaped molding material according to the present embodiment is easy to mold because the lacquer is partially uncured and softens appropriately during compression molding. In addition, because the lacquer is partially cured, the curing time during compression molding can be shortened.

[0036] The sheet-shaped molding material according to the present embodiment is preferably composed only of plant fibers and lacquer. The plant fibers are preferably composed only of cellulose.

[0037] The thickness of the sheet-shaped molding material according to the present embodiment is not particularly limited, and may be, for example, 0.1 to 2.0 mm, 0.2 to 1.8 mm, or 0.3 to 1.7 mm. By reducing the thickness of the sheet-shaped molding material according to the present embodiment, the thickness of the molded body can also be reduced.

[0038] The amount of lacquer contained in the sheet-shaped molding material according to this embodiment is preferably 20 to 65% by mass, more preferably 40 to 60% by mass, and even more preferably 50 to 60% by mass, based on the mass of the sheet-shaped molding material. By making the amount of lacquer 20% by mass or more, it is possible to obtain a sheet-shaped molding material that is uniformly impregnated with lacquer. By making the amount of lacquer 65% by mass or less, it is possible to suppress the elution of lacquer from the sheet-shaped molding material and also to suppress the stickiness of the surface of the sheet-shaped molding material.

[0039] <Molded body> One embodiment of the present invention relates to a molded article which is a compression molded product of the <sheet-shaped molding material>. The molded article according to this embodiment can maintain its durability while being thin.

[0040] The molded product according to the present embodiment may be a compression molded product of one sheet-shaped molding material, or may be a compression molded product of two or more laminated sheet-shaped molding materials. The molded product according to the present embodiment may be a compression molded product of laminated sheet-shaped molding materials and a material different from the sheet-shaped molding materials.

[0041] The thickness of the molded body according to the present embodiment is not particularly limited, but may be, for example, 0.1 mm or more, 0.1 to 10 mm, or 0.1 to 1.5 mm. The thickness of the molded body can be thinned, for example, by thinning the thickness of the sheet-shaped molding material. The thickness of the molded body can be thickened, for example, by thickening the thickness of the sheet-shaped molding material or by laminating the sheet-shaped molding material. EXAMPLES

[0042] The present invention will be described in more detail below using examples and comparative examples, but the technical scope of the present invention is not limited to these.

[0043] <Example 1> A 0.8 mm thick pure cellulose filter paper (GB003 manufactured by Global Life Science Technologies Japan, Inc.) consisting only of cotton linters (the fiber material remaining in the seeds after cotton is harvested) was impregnated with Chinese lacquer (main component: urushiol) to the content ratio (based on the mass of the lacquer-containing sheet substrate) shown in Table 1 to obtain a lacquer-containing sheet substrate. The lacquer-containing sheet substrate was heated at 120°C for 4 hours to obtain a sheet-shaped molding material.

[0044] The obtained sheet-shaped molding material was compression molded using a hot press machine at 150° C. and 6 MPa for 1 hour. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

[0045] <Examples 2 to 5> Molded bodies were obtained in the same manner as in Example 1, except that the impregnation ratio of lacquer was changed as shown in Table 1.

[0046] [Table 1]

[0047] In the production of the molded bodies, some warping occurred in the molded bodies of Examples 1 and 2, but no major problems occurred. In Example 5, lacquer was seen to seep out from the surface of the molded body, but no major problems occurred. In Examples 3 and 4, no abnormalities were observed.

[0048] <Example 6> A 0.34 mm thick pure cellulose filter paper (3MM Chr, manufactured by Global Life Science Technologies Japan, Inc.) made only of cotton linters was impregnated with Chinese lacquer (main component: urushiol) to obtain a lacquer-containing sheet substrate, with the content ratio (based on the mass of the lacquer-containing sheet substrate) shown in Table 2. The lacquer-containing sheet substrate was heated at 120°C for 2 hours to obtain a sheet-shaped molding material.

[0049] The obtained sheet-shaped molding material was compression molded using a hot press machine at 150° C. and 6 MPa for 1 hour. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

[0050] <Example 7> A molded body was obtained in the same manner as in Example 6, except that the heat treatment time after the lacquer impregnation was changed to 4 hours.

[0051] <Example 8> A 0.8 mm thick pure cellulose filter paper (GB003, manufactured by Global Life Science Technologies Japan, Inc.) made only of cotton linters was impregnated with Chinese lacquer (main component: urushiol) to obtain a lacquer-containing sheet substrate, with the content (based on the mass of the lacquer-containing sheet substrate) shown in Table 2. The lacquer-containing sheet substrate was heated at 120°C for 2 hours to obtain a sheet molding material.

[0052] The obtained sheet-shaped molding material was compression molded using a hot press machine at 150° C. and 6 MPa for 1 hour. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

[0053] <Examples 9 and 10> Molded bodies were obtained in the same manner as in Example 8, except that the heat treatment time after lacquer impregnation was changed to 4 hours and 6 hours, respectively.

[0054] <Example 11> A 1.2 mm thick pure cellulose filter paper (GB005, manufactured by Global Life Science Technologies Japan, Inc.) consisting only of cotton linters was impregnated with Chinese lacquer (main component: urushiol) to obtain a lacquer-containing sheet substrate, with the content ratio (based on the mass of the lacquer-containing sheet substrate) shown in Table 2. The lacquer-containing sheet substrate was heated at 120°C for 4 hours to obtain a sheet-shaped molding material.

[0055] The obtained sheet-shaped molding material was compression molded using a hot press machine at 150° C. and 6 MPa for 1 hour. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

[0056] <Example 12> A molded body was obtained in the same manner as in Example 11, except that the heat treatment time after the lacquer impregnation was changed to 6 hours.

[0057] [Table 2]

[0058] In the production of the molded body, some warping occurred in the molded body of Example 7, but no major problems occurred. In Examples 6 and 8, lacquer was seen to seep out from the surface of the molded body, but no major problems occurred. In Examples 9 to 12, no abnormalities were observed.

[0059] Example 1A Using a three-dimensional mold (assuming the product to be a carton) having an upper mold and a lower mold positioned opposite it, two sheets of the sheet-like molding material obtained in Example 1 were stacked and compression molded for one hour under conditions of 150°C and 6 MPa, thereby obtaining a laminated molded product in which the two sheets of sheet-like molding material were integrated.

[0060] <Examples 2A to 5A, 8A, 9A, 11A and 12A> Laminated molded articles were obtained in the same manner as in Example 1A, except that the sheet-shaped molding materials were changed to those obtained in Examples 2 to 5, 8, 9, 11 and 12, respectively.

[0061] <Physical property evaluation> The molded articles obtained in the above examples were evaluated for various physical properties by the following methods.

[0062] [Flexural strength (maximum stress), elastic modulus] A test piece (width = 10 ± 1 mm, length = 80 mm or more) was prepared using the molded body, and the bending strength (MPa) and elastic modulus (GPa) were determined with reference to JIS K 7171 (2016) Plastics - Determination of bending properties. The test was performed three times, and the average value of the three tests was taken as the bending strength (MPa) of the compression molded body. In the test, the distance between supports was 25 mm, and the crosshead speed was 1 mm / min. The measurement device used was an autograph AG-10TD manufactured by Shimadzu Corporation.

[0063] The results for the molded bodies of Examples 1 to 5 are shown in Figures 1 and 2. These results show that as the amount of lacquer impregnation increases, the bending strength and elastic modulus increase.

[0064] The results for the molded bodies of Examples 6 and 7 are shown in Figures 3 and 4. The results for the molded bodies of Examples 8 to 10 are shown in Figures 5 and 6. The results for the molded bodies of Examples 11 and 12 are shown in Figures 7 and 8. These results show that the strength can be further improved by appropriately setting the heating time of the lacquer-containing sheet-like substrate.

[0065] The results for the laminate molded bodies of Examples 1A to 5A are shown in Figures 9 and 10. The results for the laminate molded bodies of Examples 8A and 9A are shown in Figures 11 and 12. The results for the laminate molded bodies of Examples 11A and 12A are shown in Figures 13 and 14.

[0066] <Example 13> A 0.8 mm thick pure cellulose filter paper (GB003 manufactured by Global Life Science Technologies Japan, Inc.) made only of cotton linters was impregnated with Chinese lacquer (main component: urushiol) to a concentration of 50 mass% (based on the mass of the lacquer-containing sheet-like substrate) to obtain a lacquer-containing sheet-like substrate. The lacquer-containing sheet-like substrate was heated at 120°C for 2 hours to obtain a sheet-like molding material. Three sheets of the obtained sheet-like molding material were stacked and compression-molded at 150°C and 6 MPa for 1 hour to obtain a laminated molded body (thickness 2.0 mm) in which the three sheets of sheet-like molding material were integrated.

[0067] <Comparative Example 1> According to Example 1 of Japanese Patent No. 6140607, a compression molded body (thickness 2.0 mm) made of Chinese raw lacquer and cedar wood flour was produced.

[0068] An impact resistance test was carried out on the molded articles of Example 13 and Comparative Example 1. The method of the impact resistance test was as follows. The Charpy impact value was measured with reference to JIS K 7111-1 (2012) Plastics - Determination of Charpy impact properties. The test was performed nine times, and the average value of the nine tests was recorded as the Charpy impact value (kJ / m 2 In this test, the test direction was edgewise (without notch), the support distance was 62 mm, and the nominal pendulum energy was 1 J. The measurement device used was a digital impact tester manufactured by Toyo Seiki Seisakusho Co., Ltd.

[0069] As a result, the Charpy impact test value of the molded product of Comparative Example 1 was 2.56 kJ / m 2 The Charpy impact test value of the molded product of Example 13 was 8.81 kJ / m 2 and exhibited extremely excellent strength properties.

Claims

1. A step of impregnating a sheet-like substrate containing plant fibers with lacquer to obtain a lacquer-containing sheet-like substrate; A step of heating the lacquer-containing sheet-like substrate and thermally polymerizing the lacquer contained in the lacquer-containing sheet-like substrate to obtain a sheet-like molding material; A method for producing a sheet-shaped molding material comprising the steps of:

2. The thickness of the sheet-like substrate is 0.1 to 2.0 mm. The method of claim 1 .

3. The density of the sheet-like substrate is 0.10 to 0.85 g / cm 3 That is, The method according to claim 1 or 2.

4. The amount of the lacquer contained in the lacquer-containing sheet-like substrate is 30 to 70% by mass based on the mass of the lacquer-containing sheet-like substrate. The method according to any one of claims 1 to 3.

5. The heating of the lacquer-containing sheet-like substrate partially hardens the lacquer contained in the lacquer-containing sheet-like substrate. The method according to any one of claims 1 to 4.

6. The heating of the lacquer-containing sheet-like substrate is carried out at 90 to 180°C; The method according to any one of claims 1 to 5.

7. The heating of the lacquer-containing sheet-like substrate is carried out for 30 to 360 minutes; The method according to any one of claims 1 to 6.

8. A step of compression molding the sheet-shaped molding material produced by the production method according to any one of claims 1 to 7; A method for producing a molded body, comprising the steps of:

9. The compression molding is carried out at 120 to 180 ° C. The method according to claim 8.

10. The compression molding is carried out by stacking two or more sheets of the sheet-shaped molding material. The method according to claim 8 or 9.

11. A step of applying lacquer to the surface of the molded body; Further comprising: The method according to any one of claims 8 to 10.

12. A step of heating the molded body to completely harden the lacquer; Further comprising: The method according to any one of claims 8 to 11.

13. A sheet-like substrate containing plant fibers; Lacquer impregnated into the sheet-like substrate; Including, The lacquer is partially thermally polymerized. Sheet-shaped molding material.

14. The sheet-shaped molding material consists only of the plant fibers and the lacquer, The sheet-form molding material according to claim 13.

15. The thickness of the sheet-shaped molding material is 0.1 to 2.0 mm. The sheet-form molding material according to claim 13 or 14.

16. A molded product which is a compression molded product of the sheet-like molding material according to any one of claims 13 to 15.

17. The sheet-shaped molding material is laminated and compressed in two or more sheets. The molded article according to claim 16.

18. The thickness of the molded body is 0.1 mm or more. The molded article according to claim 16 or 17.

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