WO2023095778A1 - Method for manufacturing molded article with molding die produced by 3d printer and molded article - Google Patents

Abstract

[Problem] To provide: a fabric-reinforced thermoplastic resin sheet molded article in which a corner part is not extremely thinned or bored, a curved part has a beautiful finished feeling without a disorder of fabric arrangement appearing on a surface of the molded article, and a fabric-reinforced thermoplastic resin sheet does not cause interlayer delamination during molding; and a manufacturing method for efficiently manufacturing the molded article. [Solution] Provided are: a method for manufacturing a fabric-reinforced thermoplastic resin sheet molded article characterized in that a fabric-reinforced thermoplastic resin sheet is vacuum-molded using a molding die having countless micropores produced by a thermally melting lamination method (3D printer) as a female die or a male die or as a female die and a male die; and a fabric-reinforced thermoplastic resin sheet molded article obtained by vacuum-molding a fabric-reinforced thermoplastic resin sheet and characterized by using a molding die having countless micropores produced by a thermally melting lamination method that is one of molding dies for vacuum molding as a female die or a male die or as a female die and a male die.

Description

Molded product manufacturing method and molded product using mold made with 3D printer

The present invention relates to a method for producing a fabric-reinforced thermoplastic resin sheet molded product by vacuum forming using a mold prepared by a hot melt lamination method (3D printer), and molding of the vacuum-formed fabric-reinforced thermoplastic resin sheet. about goods.

Textile-reinforced thermoplastic resin sheets, in which reinforced fabrics such as carbon fiber fabrics are laminated on thermoplastic resin sheets, have high tensile strength and have good design properties in the weave of the fabric. It is used for sports equipment, musical instrument cases, suitcases, etc.

However, when a molded article having depth and corners such as a suitcase, a camera case, a musical instrument case, etc. is produced by vacuum forming using a textile-reinforced thermoplastic resin sheet, wrinkles occur in the corners of the molded article, or There are problems such as the sheets at the corners being stretched and becoming thin and the strength of the corners being extremely reduced, or the interlaminar delamination of the textile reinforced thermoplastic resin sheets. not

The present inventor has developed a carbon fiber fabric impregnated with a thermoplastic resin on both sides as a sheet that does not impair the design of the carbon fiber fabric, is lightweight, has scratch resistance, and does not delaminate or warp after vacuum forming. In addition, we proposed a molding sheet in which a laminate film of a transparent thermoplastic resin film and an unstretched thermoplastic resin film is laminated and a carbon fiber fabric is adhered to the unstretched thermoplastic resin film side (Patent Document 1). The main purpose of this molding sheet is to overcome problems such as delamination and distortion of the texture of the carbon fiber fabric that occur when molding with a metal mold. However, no satisfactory results have been obtained yet.

On the other hand, there have been many reports of attempts to apply layered manufacturing using 3D printers to the production of plastic molds (see Patent Documents 2-4, Non-Patent Documents 1-2, etc.).

For example, Patent Document 2 discloses a method of forming a thermoplastic resin sheet into the shape of a mold by vacuum forming using a mold manufactured by a three-dimensional additive manufacturing method. Patent Document 3 discloses a method in which a mold for vacuum molding is prepared using ABS resin, and synthetic paper made of polystyrene or polypropylene is vacuum-adsorbed to the mold surface.

Furthermore, in Patent Document 4, thermoplastic resin powder such as polyamide, polystyrene, polypropylene, and polyethylene is mixed with 10 to 80% by mass of spherical carbon to improve releasability. A fabricated mold is disclosed. Although it is described that this mold can also be used for vacuum molding, what is actually produced is a mold for injection molding (see FIG. 1). No molding material is disclosed.

On the other hand, in Patent Document 5, a resin sheet is formed into a predetermined shape using a molding die created by a metal stereolithography method (a method in which a large number of layers are stacked by repeating the work of sintering metal powder by irradiating a laser beam). A mold for vacuum forming is disclosed that enables improvement of the transferability of fine uneven shapes (diacut-like shape, etc.) and deep drawing forming in forming into a mold. Since this mold uses metal powder, it has drawbacks such as the weight of the mold being higher than that of resin molds, and the material cost is high. It is expected to have the function of However, since details of the molding sheet are not disclosed, the structure and properties of the sheet used for molding are unknown.

Japanese Patent Application Laid-Open No. 2021-059036 Japanese Patent Application Laid-Open No. 2001-030267 JP 2006-167947 A Japanese Patent Application Laid-Open No. 2010-234800 Japanese Unexamined Patent Application Publication No. 2010-017908

Masahiro Anzai, "How to use 3D printing technology for manufacturing" Journal of the Japan Rubber Association, Vol.87, No.9, p376, 2014 Takashi Watanabe, "Basic Knowledge of 3D Printers" Journal of Japanese Society of Prosthetics and Orthotics, Vol.32, No.3, p148, 2016

As described above, prior art documents disclose molding dies using thermoplastic resins or metal powders, which can also be applied to vacuum molding. No vacuum forming of the material is disclosed.
That is, it is a vacuum-formed product of a fabric-reinforced thermoplastic resin sheet, in which the disturbance of the fabric arrangement that appears on the surface of the molded product is suppressed (good design), and the corner portion does not become extremely thin ( It does not disclose that the strength can be maintained), the finish of the curved part is beautiful (excellent in aesthetic appearance), and the fabric-reinforced thermoplastic resin sheet does not delaminate after molding (excellent in appearance and strength).

Therefore, if it were possible to manufacture various vacuum-formed products, from small-sized products such as camera cases and lens cases to medium-sized products such as suitcases, using a textile-reinforced thermoplastic resin sheet. Therefore, it is possible to efficiently provide a convenient molded product that has a good design and is lightweight and has high strength.
On the other hand, molds made of thermoplastic resin have long been pointed out as having problems with the number of times they can be used. It can also be economically advantageous over using a mold.

The object of the present invention has been made in view of the above circumstances. To provide a fabric-reinforced thermoplastic resin sheet molded product which has a beautiful finished feeling and prevents delamination of the fabric-reinforced thermoplastic resin sheet during molding, and to provide a manufacturing method for manufacturing the molded product.

The present inventors have made intensive studies to solve the above problems, and as a result, a woven fabric-reinforced thermoplastic resin sheet is vacuum-molded using a thermoplastic resin mold produced by a hot melt lamination method using a 3D printer. The inventors have found that the above problems can be solved at once by molding, and have arrived at the present invention.

That is, in the present invention, a mold having countless fine holes produced by a fused lamination method (3D printer) is used as a female mold, a male mold, or a female mold and a male mold to produce a textile-reinforced thermoplastic resin sheet. A method for producing a textile reinforced thermoplastic resin sheet molding is provided, characterized by vacuum forming.
In addition, the present invention provides a molded article obtained by vacuum forming a textile reinforced thermoplastic resin sheet, wherein the female mold or male mold, or the female mold and male mold of the vacuum forming mold is subjected to a hot melt lamination method ( Provided is a molded product of a textile-reinforced thermoplastic resin sheet, which is characterized by using a mold having countless micropores produced by a 3D printer.

According to the present invention, the corners do not become extremely thin or have holes, and there is no disorder in the fabric arrangement that appears on the surface of the molded product, so that the finished feeling of the curved parts is beautiful. Fabric-reinforced thermoplastic resin sheet moldings can be produced without delamination of the plastic resin sheet.

In addition, using a thermoplastic resin containing a fiber reinforcement, a mold prepared by a hot melt lamination method (a method of forming a mold by repeating injection and lamination operations using a 3D printer) have holes. Unlike conventional molds, vacuum holes are not provided in advance in the mold, and vacuum can be drawn through fine holes that are formed almost uniformly over the entire surface of the mold and penetrate from the surface of the mold to the cavity. Since the air in the cavity can be exhausted in a nearly perfect state through the holes, even a hard sheet such as a woven reinforced thermoplastic resin sheet can be made to follow the shape of the mold. As a result, it is possible to obtain a textile-reinforced thermoplastic resin sheet molded product that does not cause wrinkles or holes at the corners of the molded product, does not cause delamination of the sheet, has excellent mechanical strength and appearance, and does not impair the design of the textile. can be done.

1 is a perspective view of a male mold that is an example of the mold of the present invention; FIG. 1 is a perspective view of a female mold that is an example of the mold of the present invention; FIG. 1 is a perspective view of a designed suitcase shell (male mold) that is an example of the mold of the present invention; FIG. Explanatory drawing which shows the extraction element of a shell. 3 is a photograph of the outer appearance of the shell molded in Example 1 before trimming. 4 is a photograph of the outer appearance of the corner portion of the shell before trimming formed in Example 1. FIG. 3 is an external photograph of the shell before trimming molded in Example 2. FIG. 4 is an external photograph of the shell before trimming molded in Example 3. FIG. 4 is a photograph of the appearance of the periphery of the corner portion of the shell before trimming formed in Example 3. FIG. Appearance photograph of the suitcase molded in Example 4.

The woven fabric-reinforced thermoplastic resin sheet molded article (hereinafter sometimes referred to as "molded article") of the present invention is produced by using a mold having countless fine holes produced by the hot melt lamination method (3D printer), It is made by vacuum forming a textile reinforced thermoplastic sheet.
As a mold, there are a female mold and a male mold. In the molded product and the method for manufacturing the molded product of the present invention, a mold having countless fine holes produced by a fused lamination method (3D printer) is used as the female mold. Alternatively, it can be used in either male form. Alternatively, it can be used for both female and male types.

[Mold]
As the mold, it is possible to use a mold prepared by a hot melt lamination method using a thermoplastic resin composition containing a short fiber reinforcing material and a thermoplastic resin (hereinafter referred to as "thermoplastic resin A"). preferable. The short fiber reinforcing material is used to maintain the strength of the molded mold. Without the short fiber reinforcing material, it is difficult to obtain a mold having strength enough to withstand the pressure during molding. The thermoplastic resin composition may contain additives such as ultraviolet absorbers, flame retardants, antioxidants and heat stabilizers.

As the fibers constituting the short fiber reinforcing material, high-strength non-melting fibers such as glass fibers, carbon fibers, and mineral fibers are preferable. The fiber length (average fiber length) of the short fiber reinforcing material is preferably 0.05 mm to 1 mm. When the fiber length of the short fibers is 0.05 mm or more, there is an effect of reinforcing the thermoplastic resin, and when it is 1 mm or less, when the mold is produced by the hot melt lamination method using a 3D printer, the short fibers are used in the printer nozzle. You don't have to worry about getting stuck. More preferably 0.05 mm to 0.8 mm, still more preferably 0.1 mm to 0.4 mm. As a short fiber reinforcing material, milled fiber (glass fiber, carbon fiber, etc.) is usually used because it can maintain the fiber shape even if it is a pulverized product and can improve thermal properties, dimensional stability, strength, elastic modulus, etc. pulverized) is used, but chopped fibers may also be used.

The thermoplastic resin A used in the mold is not particularly limited, and known thermoplastic resins can be used. ABS resins, polylactic acid resins, polyamide resins (nylon 6, nylon 66), polyester resins, polycarbonate resins, polyetheretherketone resins, polyetherimide resins, etc. are used because they can withstand high temperatures.
Among these, the ease of forming a mold by the hot melt lamination method, the high melt stability (that is, no heat melting) during vacuum forming of the textile reinforced thermoplastic resin sheet, and the high strength and abrasion resistance Super engineering resins such as polyamide resins such as nylon 6 and nylon 66, polyetheretherketone resins and polyetherimide resins are preferable from the viewpoint of excellent impact resistance.
The thermoplastic resin A has a melting point (T _A ) of 215° C. or more because a wide range of thermoplastic resins can be selected for forming the textile-reinforced thermoplastic resin sheet and moldability does not significantly deteriorate in relation to the molding temperature. is preferably T _A is more preferably between 215°C and 340°C.
In the present invention, the melting point of a thermoplastic resin refers to the temperature value (Tm) at the maximum peak when measured by differential scanning calorimetry (DSC) according to JIS K 7121.

The ratio (mass ratio) of the short fiber reinforcing material and the thermoplastic resin A is preferably 15:85 to 35:65, more preferably 20:80 to 35:65, still more preferably 20:80 to 30:70. . If the ratio of the short fiber reinforcement is too small, it will be difficult for the strength of the molded mold to maintain the strength required for vacuum forming, while if the ratio of the short fiber reinforcement is too high, the 3D printer will not work. The behavior of the thermoplastic resin injected from the nozzle becomes unstable.

A commercially available product can be used as the thermoplastic resin composition containing the short fiber reinforcing material, and it is usually preferable to use a commercially available product in the form of filaments. The filament diameter is not particularly limited because it varies depending on the nozzle diameter of the 3D printer.

A conventionally known method or a method equivalent thereto may be adopted as a method for manufacturing vacuum forming molds (male and female molds). For example, the design data of the target molded product is captured as 3D CAD data, and the thermoplastic resin composition containing the short fiber reinforcing material is transferred from the nozzle of the 3D printer in a state in which the thermoplastic resin A in the composition is melted. It is shaped by a method of repeating injection and stacking operations (laminate manufacturing method).

The nozzle diameter of the 3D printer to be used is preferably in the range of 0.2 mm to 1.2 mm from the viewpoint of pore formation, pore size, mold strength, etc. When the nozzle diameter is 0.2 mm or more, the diameter of the thermoplastic resin composition to be injected does not become extremely small, and the injected thermoplastic resins A are fused to form voids in the mold. Since it is no longer necessary, there is no problem such as extreme difficulty in exhausting air during vacuum forming. In addition, it is possible to avoid the inconvenience of requiring a long time for shaping the mold due to the increased number of layers. On the other hand, if the nozzle diameter is 1.2 mm or less, the diameter of the thermoplastic resin composition to be injected does not become extremely large, and a mold having a smooth surface while having a cavity inside can be formed. . The nozzle diameter of the 3D printer is more preferably 0.3 mm to 1.1 mm, more preferably 0.4 mm to 1.0 mm.

The nozzle temperature when injecting the molten short fiber reinforcing material-containing thermoplastic resin composition from the nozzle of the 3D printer varies depending on the type of thermoplastic resin A, but is preferably 270 ° C. to 310 ° C., more preferably 280 ° C. ~300°C. Further, the temperature of the bed on which the molten short fiber reinforcing material-containing thermoplastic resin composition is laminated is preferably 80°C to 90°C. The material of the bed is not particularly limited, and examples thereof include epoxy resin, glass, and ceramics.

The female mold and male mold formed using a 3D printer are arranged in a direction perpendicular to the length direction of the filaments of the laminated short fiber reinforcing material-containing thermoplastic resin composition (i.e., the direction penetrating the mold wall). It is modeled in a state of having fine pores. The reason why fine pores are formed in the direction perpendicular to the length direction of the filament is not clear, but it is speculated that it is due to variations in the amount of ejected thermoplastic resin A, fluctuations in the operation of the 3D printer, etc. be done. Although the number of holes and the size of the holes in the mold of the present invention are not certain, the density of the mold is usually 60% to 95% of the density of the material of the mold before molding. If the density ratio is less than 60%, the strength of the mold is insufficient, and the mold may be deformed during vacuum forming. On the other hand, if the density ratio exceeds 95%, the mold becomes too dense, and there is a possibility that sufficient air cannot be sucked and vacuum forming cannot be performed. More preferably 65% to 95%, still more preferably 75% to 95%. The density of the mold can be adjusted by creating 3D data and 3D printing so that voids are formed inside.
The material of the molding die and the density of the molding die can be measured, for example, according to JIS K 7112:1999 "Plastics-Determination of density and specific gravity of non-foamed plastics".

In the present invention, a mold for vacuum forming can be used as a female mold, a male mold, or a female mold and a male mold. The female or male mold may be placed in either the upper mold or the lower mold. For example, when the mold of the present invention is used only for the female mold, the male mold can be made of gypsum, wood, wood chips (plastic wood), tooling plastics, low-melting alloys, or the like. Conversely, when the mold of the present invention is used only for the male mold, a mold made of gypsum, wooden mold, wood chips (plastic wood), tooling plastics, low-melting alloy, etc. can be used for the female mold. can be done.
In addition, in order to make it easier to peel off the textile reinforced thermoplastic resin sheet molded product from the mold, a mold release agent such as fluorine, silicone, wax, or surfactant is applied in the amount normally used. You can

Examples of molds (male mold and female mold) used in the present invention are shown in FIGS. 1 and 2. FIG. FIG. 3 is a view showing a designed suitcase shell (male mold), which is an example of the mold of the present invention. Also, FIG. 4 is an explanatory view showing extraction elements of a suitcase (shell), and the circled parts (corners, caster mounting parts, side steps and ribs around the circumference) are formed in the mold shown in FIG. reflected.
The mold shown in FIGS. 1 and 2 is made of a thermoplastic resin composition containing 20% by mass of powdered carbon fibers as a short fiber reinforcing material. Although the fiber length (average fiber length) of powdery carbon fibers is not certain, it is presumed to be about 0.05 mm to 0.2 mm.

The molded product of the present invention is a molded product having a corner portion (a corner portion near a right angle) and a caster mounting portion, which is obtained using the above mold, and is formed by vacuum forming with a conventional mold (mold). It is characterized by remarkably improving defects found in products.
In other words, with a conventional mold, for example, when a carbon fiber fabric reinforced thermoplastic resin sheet is used for deep drawing, the height (depth) of the molded product from the bottom is limited to 20 mm to 30 mm. However, by using the molding die of the present invention, it is possible to deep draw a molded article having a height (depth) of 40 mm or more, preferably 50 mm to 100 mm.
In addition, according to the molded product of the present invention, the drawbacks of molding with a conventional mold are the thinning and perforation phenomenon at the corners of the molded product and the caster mounting portion, and the disorder of the fabric structure on the surface of the molded product. , distortion of the entire molded product, etc. can be remarkably improved. When the molded product is used for box-shaped cases, bags, etc., there are usually eight corner portions, so the effect of improving the disadvantages of conventional molds is remarkable.

[Molding method]
In the method for producing the molded article of the present invention, a conventionally known vacuum molding apparatus and molding method can be applied, except for using a mold having countless fine holes produced by a fused lamination method (3D printer) (Patent No. 6890035, etc.). That is, in the method for producing a fabric-reinforced thermoplastic resin sheet molded product of the present invention, a mold having a myriad of micropores prepared by a hot-melt lamination method is used, and the fabric-reinforced thermoplastic resin sheet is vacuumed from the entire surface of the mold. It is manufactured by molding.
According to the present invention, since the male and female dies for vacuum forming have a large number of fine pores in the direction perpendicular to the length direction of the filament, the fabric-reinforced thermoplastic resin molded article can be obtained by vacuum forming. Since the air in the corners and bends of the mold is effectively exhausted during molding, the woven reinforced thermoplastic resin sheet adheres to the mold and does not cause wrinkles, etc., and has excellent strength and design. A molded product can be obtained.

The molding temperature is desirably a temperature near the melting point of the thermoplastic resin (hereinafter referred to as "thermoplastic resin B") that constitutes the textile-reinforced thermoplastic resin sheet. Here, the molding temperature refers to the maximum surface temperature of the fabric-reinforced thermoplastic resin sheet (material), which is the value measured with a non-contact temperature measuring device.
From the viewpoint of balancing the thermal stability and moldability of the mold, the difference between the molding temperature and the melting point of the thermoplastic resin A is preferably 10°C or more, more preferably 20°C to 90°C. Further, the molding temperature is desirably equal to or higher than the Vicat softening point of the thermoplastic resin B. The material heating time is not particularly limited, but is usually heated for 30 seconds to 300 seconds.

The clearance between the male mold and the female mold during vacuum forming varies depending on the thickness of the fabric-reinforced thermoplastic resin sheet used for molding, but is usually designed to be 80% to 90% of the thickness of the sheet. preferable. The wall thickness of the male and female dies varies depending on the type of the desired fabric-reinforced thermoplastic resin molded product. is preferred.
Then, the fabric-reinforced thermoplastic resin sheet is placed on the male mold (or female mold), and while the female mold (or male mold) is pushed in, vacuum is drawn from the lower part of the male mold (or female mold) to form. Thus, the fiber-reinforced thermoplastic resin molded article of the present invention is obtained.

[Textile reinforced thermoplastic resin sheet]
In the present invention, a composite sheet of a textile and a thermoplastic resin can be widely used as the textile-reinforced thermoplastic resin sheet used as a material for the fiber-reinforced thermoplastic resin sheet molded product.
The woven fabric used for the woven fabric-reinforced thermoplastic resin sheet is preferably a woven fabric woven with fibers having a low tensile elongation and a high tensile strength. Examples thereof include carbon fiber fabrics, vegetable fiber fabrics, flat yarn fabrics, and the like. Among them, carbon fiber fabrics and flat yarn fabrics are more preferable, and carbon fiber fabrics are particularly preferable, from the viewpoint of fiber strength and excellent design.
As the flat yarn fabric, the one described in Japanese Patent No. 6890035 can be used.

The carbon fiber fabric, vegetable fiber fabric, and flat yarn fabric may be fabrics obtained by weaving carbon fibers, vegetable fibers, or flat yarns by conventional methods, and include plain fabrics, twill fabrics, satin fabrics, and the like. . The woven fabric is not only excellent in shape stability and strength of molded articles, but also excellent in design.

The basis weight of the woven fabric is preferably 30 g/m ² to 200 g/m ² , more preferably 40 g/m ² to 150 g/m ² , particularly preferably 50 g/m ² to 100 g/m ² . If the basis weight is too large, the moldability of the woven fabric-reinforced thermoplastic resin sheet tends to be poor, and if the basis weight is too small, the strength of the molded product will be insufficient. The width of the threads forming the woven fabric is preferably 1 mm to 5 mm, more preferably 2 mm to 5 mm, from the viewpoint of designability and formability.

As the thermoplastic resin B constituting the textile-reinforced thermoplastic resin sheet, a resin having a melting point (T _B ) of 120° C. to 220° C. is preferable in view of the molding temperature of the sheet. Polyolefin-based resins such as polypropylene resins, polyamide-based resins, and modified resins thereof are preferred from the viewpoint of resin cost, moldability, and surface appearance.
The difference in melting point between T _A and T _B (T _A −T _B ) is preferably (T _A −T _B )≧0° C. from the viewpoint of maintaining stability during vacuum forming. The preferable thermoplastic resin constituting the textile-reinforced thermoplastic resin sheet is a polyolefin-based resin or a polyamide-based resin, and the preferable melting point (T _A ) of the thermoplastic resin for forming the mold is 215° C. or higher. Considering the points and the like, the difference between T _A and T _B (T _A -T _B ) is preferably 10°C to 20°C, more preferably 20°C to 30°C.

The woven fabric-reinforced thermoplastic resin sheet is not particularly limited as long as it is a sheet composed of woven fabric and thermoplastic resin, and commercially available products can also be used. The thickness of the woven fabric-reinforced thermoplastic resin sheet is not particularly limited as long as it is a thickness that can be molded. In general, 0.5 mm to 3 mm is preferred. If the thickness is too small, the molded product is likely to be perforated and wrinkled, and the strength of the molded product is also reduced. On the other hand, if the thickness is too large, the molding itself becomes difficult. The thickness of the textile reinforced thermoplastic resin sheet is more preferably 0.75 mm to 2.8 mm, still more preferably 1 mm to 2.5 mm.

The volume content (Vf) of fibers in the fabric-reinforced thermoplastic resin sheet is preferably 15% to 55%. If the volume content of the fibers is too high, the thermoplastic resin B becomes difficult to penetrate into the interior of the woven fabric, which may reduce the adhesion between the woven fabric and the thermoplastic resin sheet. On the other hand, if the fiber volume content is too low, the orientation of the woven fabric tends to be disturbed during molding, and the strength of the molded product tends to decrease. The volume fraction (Vf) of the fibers is more preferably 20% to 50%, still more preferably 30% to 50%, and particularly preferably 40% to 50%.

As the fabric constituting the fabric-reinforced thermoplastic resin sheet, a narrow sheet obtained by cutting a carbon fiber-reinforced thermoplastic resin sheet impregnated with a thermoplastic resin into a narrow tape shape is described in Japanese Patent No. 4324649. Alternatively, a carbon fiber fabric obtained by impregnating the carbon fiber fabric with a thermoplastic resin in advance may be used. The use of a woven fabric pre-impregnated with a thermoplastic resin is effective in preventing the formation of voids in the molded product and the separation of the molding sheet. In addition, since the fibers can be laminated and integrated without disturbing the orientation of the fibers, it is easy to obtain a molded product with excellent design. As the carbon fiber reinforced thermoplastic resin sheet for obtaining the narrow sheet, for example, a thermoplastic resin nonwoven fabric or sheet is superimposed on a fiber sheet in which a plurality of carbon fiber bundles are spread, and heated. A carbon fiber impregnated with a molten thermoplastic resin B by applying pressure may be mentioned.

In addition, as the thermoplastic resin sheet constituting the textile-reinforced thermoplastic resin sheet, a decorative sheet obtained by laminating and integrating a transparent resin film layer as the outermost layer on at least one side may be used ( For example, see JP-A-2021-059036). By laminating a transparent resin film as the outermost layer, the scratch resistance, decorativeness, etc. of the molded product can be improved.

As the transparent thermoplastic resin film that constitutes the transparent resin film layer, a polyethylene terephthalate (PET)-based film, a polyamide (PA)-based film, a polypropylene (PP)-based film, etc. have high transparency and are excellent in decorativeness. A resin film is preferred. More preferred are APET films, GPET films, or biaxially oriented PET films, which are amorphous and have transparency and surface gloss comparable to glass.
The transparent resin film layer is more preferably dry-laminated or heat-laminated with a transparent thermoplastic resin film and an unstretched thermoplastic resin film. In this case, the carbon fiber fabric or the like is laminated with the unstretched thermoplastic resin film that constitutes the transparent resin film layer. The carbon fiber fabric and the unstretched thermoplastic resin film may be laminated via an adhesive resin. By using a pre-laminated film, the transparent thermoplastic resin film (outer layer film) and the unstretched thermoplastic resin film (inner layer film) can be reliably adhered. In addition, by forming the outer layer film from a high-melting point resin and the inner layer film from a low-melting point resin, it is possible to prevent wrinkles from occurring in the outer layer film, which is not adhered to the carbon fiber fabric or the like, during molding. Decorative properties can be maintained. Furthermore, a thermoplastic resin having good adhesion to the carbon fiber fabric can be selected as the inner layer film.

The thickness of the transparent thermoplastic resin film is preferably 15 μm to 50 μm, more preferably 20 μm to 40 μm, considering the decorativeness, moldability, strength, etc. of the outermost layer of the molded product. If the thickness is too small, there is a concern that pinholes will form in the sheet and the decorativeness will deteriorate. is generated, and there is a possibility that the decorativeness is also deteriorated.

As the non-stretched thermoplastic resin film, a film made of a resin that is transparent and has excellent adhesion to carbon fiber fabrics, etc. is used. A polypropylene resin is more preferable. Polypropylene-based resins are homo- or copolymers containing polypropylene as a main component, and specifically include homopolypropylene resins, ethylene-propylene random copolymers, ethylene-propylene block copolymers, and propylene and 4 carbon atoms. A copolymer of ~20 α-olefins (butene-1, 4-methylpentene-1, hexene-1, octene-1, etc.), etc., and modifiers commonly used for softening polypropylene resins are added. It's okay to be. The polypropylene-based resin film is preferably a cast polypropylene (CPP) film. The thickness of the CPP film is preferably 15 μm to 80 μm, more preferably 20 μm to 50 μm.

When an adhesive resin is used to bond the carbon fiber fabric and the unstretched thermoplastic resin film, the adhesive resin is preferably a modified polyolefin resin because of its excellent transparency and adhesiveness. The modified polyolefin resin can be appropriately selected from known ones and used, but acid-modified polyolefin resins such as maleic anhydride-modified polyethylene and maleic anhydride-modified polypropylene are preferably used. The adhesive resin used is formed into a film shape.

The decorative sheet is obtained by laminating, for example, a carbon fiber fabric on the non-stretching thermoplastic resin sheet side of the transparent resin film obtained by laminating the transparent thermoplastic resin sheet and the non-stretching thermoplastic resin sheet. A transparent resin sheet is laminated on the non-stretched thermoplastic resin sheet side, and the carbon fiber fabric and the non-stretched thermoplastic resin sheet are adhered by heating and pressurizing.

The thickness of the decorative sheet varies depending on the desired fiber-reinforced thermoplastic resin molded article, but is usually preferably 0.5 mm to 3 mm.
A plurality of decorative sheets may be laminated and used according to the desired thickness of the molded product. In this case, since the transparent thermoplastic resin sheets of the outermost layers are overlaid, they can be laminated via the adhesive resin. As the adhesive resin, the same adhesive resin sheet as used for bonding the carbonaceous fabric or the like and the unstretched thermoplastic resin sheet can be used.

In addition, each material constituting the textile-reinforced thermoplastic resin sheet of the present invention includes an ultraviolet absorber, a flame retardant, an antioxidant, a heat stabilizer, an antistatic agent, a pigment, and a coloring agent within a range that does not impair the effects of the present invention. Additives such as agents and nucleating agents may be blended. When a coloring agent is added, it is desirable to add it to the outermost layer film.

The method for producing a textile-reinforced thermoplastic resin sheet molded product of the present invention can be applied not only to vacuum forming but also to pressure vacuum forming.

In addition, the textile-reinforced thermoplastic resin sheet molded product of the present invention is free from wrinkles and holes at corners and bends, and can be imparted with strength and design. Decorative sheets for sports equipment, musical instruments, etc., or storage cases such as suitcases, attaché cases, waist pouches, wallets, camera cases, lens cases, musical instrument cases; covers for switches, etc.; It can be suitably used as interior parts and exterior parts; electronic equipment housings, casings, wall materials, ceiling materials, panels, bicycle parts; and the like.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited only to the following examples.

(Production example 1)
[Modeling of male and female molds by 3D printer]
(1) Manufacturing shape Autodesk Fusion360 was used for shape design.
・Male type 170 mm × 170 mm × 80 mm Prototype shape (Fig. 1)
・ Female mold 200 mm × 200 mm × 95 mm Prototype shape (Fig. 2)
・Male type 360 mm x 480 mm x 100 mm suitcase shape (Fig. 3)
・Female mold 390mm x 510mm x 115mm suitcase shape The wall thickness of the male mold is 2.4mm, the wall thickness of the female mold is 2.4mm, and the clearance between the male and female molds is designed to be 1mm. .

(2) Equipment used 3D printer: NJB-777 (manufactured by NINJABOT) (Printable area: 700mm x 700mm x 700mm)
・Nozzle diameter: 0.8mm
・Discharge speed: 30mm/sec
・Filament: PA6-CF manufactured by Polymaker (milled carbon fiber: nylon 6 resin = 20:80 (mass ratio), diameter: 1.75 mm (trade name: PolyMide PA6-CF)

(3) Modeling The male (Fig. 1) and female (Fig. 2) prototype shapes are based on the already designed suitcase shape (Fig. 3), and only the necessary shapes are extracted and redesigned. was performed. The extracted elements are as follows. The circled areas shown in FIG. 4 indicate extraction elements.
・Shape of four corners (including caster mounting part)
・Steps on the side ・Rib shape all around ・Caster mounting part

Set the bed (glass fiber / epoxy resin) temperature to 80 ° C. and the nozzle temperature of the 3D printer to 300 ° C., and laminate it on the bed while discharging so that the thickness of the carbon fiber-containing thermoplastic resin layer is 0.4 mm. , male and female molds were molded (FIGS. 1-2).
The time required for shaping the male mold (Fig. 1) was about 12 hours, and the time required for shaping the female mold (Fig. 2) was about 18 hours.

(Example 1)
Male and female molds were used which were shaped into prototype shapes using a 3D printer. All elements (4 elements) were extracted.
A fabric-reinforced thermoplastic resin sheet 1 described below was placed on the formed female mold. After that, before the male mold (upper mold) starts to descend and comes into contact with the sheet 1, vacuum suction is performed from the surface of the female mold (lower mold), and the vacuum suction from the surface of the male mold is performed immediately after matching. A time difference of about 1 second was provided for the vacuum suction of the male and female molds. The surface temperature of sheet 1 during molding was 130 to 150° C., and the heating time was 60 seconds.
As a result of visually observing the appearance of the molded product, it was found that there were no wrinkles on the surface and four corners of the molded product, there was little misalignment of the fabric, and the texture pattern was clearly confirmed. The corners did not become thin and there were no holes. Also, no delamination of the fabric-reinforced thermoplastic resin sheet was observed. Fig. 5 shows the appearance of the molded product.
The thickness of the fabric reinforced thermoplastic sheet was greater than the mold clearance, but the sheet was flexible and easy to mold.

[Textile reinforced thermoplastic resin sheet 1]
A flat yarn laminate sheet (thickness: 1.8 mm, Vf : 40%).
The material composition of the flat yarn laminate sheet is as follows.
・Flat yarn woven fabric: twill fabric (basis weight: 110 g/m ² ) of flat yarn (yarn width: 3 mm, fineness: 1,500 dtex) made of drawn threads of polypropylene slit yarn with a melting point of 160 ° C.
・Thermoplastic resin layer: ethylene-propylene random copolymer resin with a melting point of 146 ° C. ・Adhesive resin layer: commercially available polar polyolefin ・Outermost layer: A-PET with a thickness of 50 μm

(Example 2)
As extraction elements, a mold was used in which the shape of the four corners (excluding caster mounting portions) was extracted and shaped. The mold was modeled in the same manner as in Example 1 (3D printer).
A fabric-reinforced thermoplastic resin sheet 2 described below was placed on the formed female mold. After that, before the male mold (upper mold) starts to descend and comes into contact with the sheet 2, vacuum suction is performed from the surface of the female mold (lower mold), and the vacuum suction from the surface of the male mold is performed immediately after matching. A time difference of about 1 second was provided for the vacuum suction of the male and female molds. The sheet 2 had a surface temperature of 145 to 200° C. and a heating time of 45 to 75 seconds.
As a result of visually observing the appearance of the molded product, it was found that there were no wrinkles on the surface and four corners of the molded product, there was little misalignment of the fabric, and the texture pattern was clearly confirmed. The corners did not become thin and there were no holes. Also, no delamination of the fabric-reinforced thermoplastic resin sheet was observed. However, the releasability of the sheet 2 from the upper mold was poor. Fig. 6 shows the appearance of the molded product.

[Textile reinforced thermoplastic resin sheet 2]
Carbon fiber fabric (twill fabric) sheet (thickness: 1 mm, Vf: 45%) impregnated with polyamide resin (nylon 6) having a melting point of 220°C. Note that the carbon fiber fabric may be a plain weave fabric.

(Example 3)
As extraction elements, a mold was used which was shaped by extracting the shape of the four corners (excluding the caster mounting portion), the step on the side surface, and the shape of the ribs around the circumference. The male mold (upper mold) used a mold made of plastic wood (wood chips), and the female mold (lower mold) was modeled in the same manner as in Example 1 (3D printer). In this example, the clearance between the male and female dies was set to 1.5 mm.
A fabric-reinforced thermoplastic resin sheet 3 described below was placed on the female mold. After that, before the male mold starts to descend and comes into contact with the sheet 3, vacuum suction is applied from the surface of the female mold. A time difference of about 1 second was provided for vacuum suction. The sheet 3 had a surface temperature of 185 to 195° C. and a heating time of 70 to 120 seconds.
As a result of visually observing the appearance of the molded product, it was found that there were no wrinkles on the surface and four corners of the molded product, there was little misalignment of the fabric, and the texture pattern was clearly confirmed. The corners did not become thin and there were no holes. No delamination of the fabric reinforced thermoplastic resin sheet was observed. In addition, the releasability of the sheet 3 from the upper mold was also good. Fig. 7 shows the appearance of the molded product.

[Textile reinforced thermoplastic resin sheet 3]
Carbon fiber fabric (twill fabric) sheet (thickness: 1.3 mm, Vf: 46%) impregnated with polyamide resin (nylon 6) having a melting point of 220°C. Note that the carbon fiber fabric may be a plain weave fabric.

(Example 4)
Male and female molds shaped into a suitcase shape were used. A mold made of plastic wood (wood chips) was used as the male mold (upper mold), and a mold made by a 3D printer was used as the female mold (lower mold). In this example, the clearance between the male and female dies was set to 1.5 mm.
A fabric-reinforced thermoplastic resin sheet 4 described below was placed on the female mold. After that, before the male mold starts to descend and comes into contact with the sheet 4, vacuum suction is applied from the surface of the female mold. A time difference of about 1 second was provided for vacuum suction. The surface temperature of the sheet 4 was 130-150° C., and the heating time was 28-35 seconds.
As a result of visually observing the appearance of the molded product, the surface of the molded product had no wrinkles at all, but some wrinkles were observed at the four corners. There was no misalignment of the woven fabric, and the texture pattern was clearly confirmed. The corners did not become thin and there were no holes. Also, no delamination of the fabric-reinforced thermoplastic resin sheet was observed. FIG. 8 shows the appearance of a suitcase made from the obtained molded product.

[Textile reinforced thermoplastic resin sheet 4]
Carbon fiber fabric (twill fabric) sheet (thickness: 0.75 mm, Vf: 46%) impregnated with polypropylene resin having a melting point of 160°C.

(Test example 1)
Using the female and male molds molded in Production Example 1, the fabric-reinforced thermoplastic resin sheet 4 was vacuum-molded at a surface temperature of 150°C for 50 seconds, but the molding did not follow the shape of the mold. No molding was obtained.

(Test example 2)
Using the female and male molds formed in Production Example 1, a fabric-reinforced thermoplastic resin sheet 4 was vacuum-formed at a surface temperature of 150 to 170° C. for a heating time of 60 to 70 seconds. A molded product could be obtained, but the sheet could not be released from the upper mold.

From the above results, according to the production method of the present invention, there is no disorder in the fabric arrangement that appears on the surface of the molded product, and the design is excellent. In addition, since the corners do not become extremely thin, the strength does not decrease, and the fabric-reinforced thermoplastic resin sheet after molding does not delaminate, so that a molded product with excellent appearance and strength can be obtained. This is because the mold formed by a 3D printer is in a state in which countless fine holes are open, and by performing vacuum forming using the mold, the fine holes can be used to uniformly evacuate the mold. It is presumed that the sheet was brought into close contact with the mold because the air inside was able to be evenly expelled out of the mold.

(Test example 3)
Using the same mold as in Example 3, a short fiber reinforced thermoplastic resin sheet (thickness: 1 mm, Vf: 20%) was vacuum molded.

Example 3 except that the heater set temperatures of the upper mold (male mold) and lower mold (female mold), the heating time of the short fiber reinforced thermoplastic resin sheet, and the measured temperature of the material surface were set to the values shown in Table 1. Vacuum forming was performed in the same manner as The results are summarized in Table 1.

From the results in Table 1, it can be seen that by molding at a temperature higher than the Vicat softening point of nylon 6 resin and lower than the melting point, a molded product free from sheet cracking and breakage can be obtained. In addition, it can be seen that the molded article molded at a temperature near the melting point has excellent surface appearance characteristics.
Even if normal materials (solid materials such as polypropylene, ABS, polycarbonate, etc.) are molded at a temperature at which the material melts down, the thermoplastic resin sheet containing non-melting fibers (carbon fibers) has a higher molding temperature than the resin alone. Molding temperatures have been found to be desirable.

By using the molding die of the present invention, it is possible to obtain a molded product by deep drawing a fabric-reinforced thermoplastic resin sheet to a height (depth) of 50 mm to 100 mm from the bottom of the molded product. Moreover, the molded fabric-reinforced thermoplastic resin sheet molded product does not have holes at the corners or bends, and does not become extremely thin. Therefore, there is a possibility that it can be widely used for forming various products that could not be conventionally deep drawn.

Claims (13)

It is characterized by vacuum forming a fabric-reinforced thermoplastic resin sheet using a mold with countless micropores made by a fused lamination method (3D printer) as a female mold, a male mold, or a female mold and a male mold. A method for producing a textile reinforced thermoplastic resin sheet molding. The mold is formed of a thermoplastic resin composition containing 15% by mass to 35% by mass of a short fiber reinforcing material, and the density of the mold is 60% to 60% of the density of the material of the mold before molding. is 95%;
The method for manufacturing the textile reinforced thermoplastic resin sheet molding according to claim 1. When the melting point of the thermoplastic resin A forming the mold is T _A and the melting point of the thermoplastic resin B forming the textile reinforced thermoplastic resin sheet is T _B ,
satisfies the relationship (T _A −T _B )≧0° C.,
The method for manufacturing the textile reinforced thermoplastic resin sheet molding according to claim 2. The thermoplastic resin A forming the mold is one selected from ABS resin, polylactic acid resin, polyamide resin, polyester resin, polycarbonate resin, polyetheretherketone resin, or polyetherimide resin,
The short fiber reinforcing material is a non-melting fiber with a fiber length of 0.05 mm to 1 mm,
4. The method for manufacturing the textile-reinforced thermoplastic resin sheet molding according to claim 3. The textile reinforced thermoplastic resin sheet has a thickness of 0.5 mm to 3.0 mm and a fiber volume content (Vf) of 15% to 55%.
The method for manufacturing the textile reinforced thermoplastic resin sheet molding according to claim 1. A molded product obtained by vacuum forming a textile reinforced thermoplastic resin sheet,
Among vacuum forming molds, the female mold, the male mold, or the female mold and the male mold are characterized by using a mold having countless fine holes produced by a fused lamination method (3D printer). , textile reinforced thermoplastic resin sheet moldings. The textile-reinforced thermoplastic resin sheet molded product according to claim 6, wherein the height (depth) from the bottom surface of the molded product is 40 mm or more. The fabric constituting the fabric-reinforced thermoplastic resin sheet is at least one selected from carbon fiber fabrics, vegetable fiber fabrics and flat yarn fabrics.
The textile reinforced thermoplastic resin sheet molding according to claim 6. The thermoplastic resin B constituting the textile reinforced thermoplastic resin sheet is a resin having a melting point of 120 ° C. to 220 ° C.
The textile reinforced thermoplastic resin sheet molding according to claim 6. The thermoplastic resin B is a polyolefin-based resin or a polyamide-based resin,
The textile reinforced thermoplastic resin sheet molding according to claim 9. The textile reinforced thermoplastic resin sheet is a decorative sheet,
The decorative sheet comprises a laminated film of a transparent thermoplastic resin film and an unstretched thermoplastic resin film, which is laminated on one side of the textile-reinforced thermoplastic resin sheet (the side that will become the surface of the molded product). is laminated so that is on the outside,
The textile reinforced thermoplastic resin sheet molding according to claim 6. The transparent thermoplastic resin film is one selected from a polyethylene terephthalate resin film, a polyamide resin film, or a homopolypropylene resin film,
The unstretched thermoplastic resin film is one selected from a polypropylene resin film, an ethylene-propylene random copolymer film, and an ethylene-propylene block copolymer film.
The textile reinforced thermoplastic resin sheet molding according to claim 11. The molded article is at least one selected from camera cases, lens cases, attache cases, suitcases, and musical instrument cases.
The textile reinforced thermoplastic resin sheet molding according to claim 6.

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