JP6493159B2 - Exterior reinforcing sheet and molded body - Google Patents

Description

  The present invention relates to an exterior reinforcing sheet and a molded body. Specifically, the present invention provides an exterior reinforcing sheet containing inorganic reinforcing fibers, natural pulp fibers, and a binder component, and the exterior reinforcing sheet is disposed on at least one surface of a thermoplastic resin-containing member. It is related with the molded object formed.

  Conventionally, fiber sheets made of glass fibers, carbon fibers, and pulp fibers are known. Such a fiber sheet can be obtained by dispersing each fiber in water or air and making it into a sheet. Although the fiber sheet is used for various uses, in recent years, it is also used for the application of bonding to the surface of building materials such as interior materials. Since the interior material is required to have mechanical strength, it has been studied to increase the mechanical strength of the entire interior material by laminating a fiber sheet.

  For example, Patent Documents 1 to 3 disclose a fiber sheet laminated on the surface of a core material such as a foam sheet, and a laminate (molded body) formed by molding the core material and the fiber sheet. In Patent Document 1, a glass fiber sheet or a carbon fiber sheet is used as the fiber sheet. In patent document 2, the sheet | seat which consists of a reinforced fiber and a thermoplastic resin fiber is used as a fiber sheet. Patent Document 3 discloses a laminate in which a non-foamed layer is laminated on both surfaces of a foamed layer. As the non-foamed layer, a film made of a thermoplastic resin or a thermosetting resin, a fiber sheet, a thermoplastic resin. A sheet in which reinforced fibers and the like are combined is disclosed.

  In patent documents 1-3, it is supposed that a foaming core material can be reinforced by forming a molded object and a laminated body using a fiber sheet, and mechanical strength can be raised. Furthermore, increasing the lightness and sound absorption is also being studied, and application to interior materials for vehicles is also expected.

JP 2001-121638 A JP 2002-205350 A JP 2006-321159 A

  As described above, when a molded body is formed by arranging a conventional fiber sheet on the surface layer, the strength can be increased to some extent. However, there are cases where the adhesion between the fiber sheet after molding and the core material is not good, and in such a case, there is a problem that the strength of the molded body cannot be sufficiently increased.

  Moreover, the molded object shape | molded by arrange | positioning a fiber sheet on the surface layer is also used as a vehicle interior material. Since the surface of the vehicle interior material may be in direct contact with the skin of a person riding on the vehicle, a good surface texture or the like is also required for the surface of the molded body. However, when the conventional fiber sheet is used, the surface texture of the vehicle interior material may be inferior, and improvement has been demanded.

  Therefore, in order to solve the problems of the prior art, the present inventors are an exterior reinforcing sheet that can increase the strength when laminated and molded on a core material, Investigations were conducted with the aim of providing a sheet for exterior reinforcement with good adhesion. Furthermore, the present inventors have also studied for the purpose of providing an exterior reinforcing sheet capable of improving the surface texture of the molded body.

As a result of intensive studies to solve the above problems, the present inventors have determined that the content of the binder component is within a predetermined range in the exterior reinforcing sheet including inorganic reinforcing fibers, natural pulp fibers, and the binder component. As a result, it was found that a molded article having excellent strength and improved surface texture was obtained.
Specifically, the present invention has the following configuration.

[1] An exterior reinforcement sheet containing inorganic reinforcing fibers, natural pulp fibers, and a binder component, wherein the content of the binder component is 25% by mass or less based on the total mass of the exterior reinforcement sheet. Sheet.
[2] The exterior reinforcing sheet according to [1], wherein the content of the natural pulp fiber is 20% by mass to 80% by mass with respect to the total mass of the inorganic reinforcing fiber and the natural pulp fiber.
[3] The exterior reinforcing sheet according to [1] or [2], wherein the content of the natural pulp fiber is 15% by mass or more based on the total mass of the exterior reinforcing sheet.
[4] The exterior reinforcing sheet according to any one of [1] to [3], wherein the basis weight is 10 g / m ² or more and 120 g / m ² or less.
[5] The exterior reinforcing sheet according to any one of [1] to [4], wherein the density is 0.03 g / cm ³ or more and 0.9 g / cm ³ or less.
[6] The exterior reinforcing sheet according to any one of [1] to [5], wherein the inorganic reinforcing fiber has a fiber diameter of 3 μm or more and 15 μm or less.
[7] The exterior reinforcing sheet according to any one of [1] to [6], wherein the fiber length of the inorganic reinforcing fiber is 3 mm or more and 35 mm or less.
[8] A molded article formed by disposing the exterior reinforcing sheet according to any one of [1] to [7] on at least one surface of the thermoplastic resin-containing member.
[9] The molded product according to [8], which is used as an automobile interior member.

  ADVANTAGE OF THE INVENTION According to this invention, the sheet | seat for exterior reinforcement which can improve the intensity | strength and surface texture of a molded object can be obtained. The exterior reinforcing sheet of the present invention is preferably used as a sheet constituting a surface layer of a member that directly touches human skin such as a vehicle interior material.

FIG. 1 is a diagram for explaining a configuration of a molded body obtained by laminating a sheet for exterior reinforcement of the present invention on a thermoplastic resin-containing member (core material) and a method for evaluating the adhesion between the sheet for exterior reinforcement and the core material. It is.

  Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be made based on representative embodiments and specific examples, but the present invention is not limited to such embodiments.

(Exterior reinforcement sheet)
The present invention relates to an exterior reinforcing sheet including inorganic reinforcing fibers, natural pulp fibers, and a binder component. Here, content of a binder component is 25 mass% or less with respect to the total mass of the sheet | seat for exterior reinforcement.
Since the exterior reinforcing sheet of the present invention has the above-described configuration, the strength of the molded body obtained by laminating the core material containing a thermoplastic resin (hereinafter also referred to as a thermoplastic resin-containing member) and performing heat-pressure molding is obtained. Can be increased. Moreover, the sheet | seat for exterior reinforcement of this invention is also characterized by the high adhesiveness with the core material containing a thermoplastic resin. Furthermore, since the molded body formed from the exterior reinforcing sheet of the present invention and the thermoplastic resin-containing member contains natural pulp fibers on the surface, the surface texture is also excellent. Here, the good surface texture means that the tactile sensation when touching the surface of the molded body is flexible. Specifically, the tingling sensation and the sensation of the surface (stiff) are reduced. It means being.
As described above, the exterior reinforcing sheet of the present invention is bonded to the surface (exterior) of a thermoplastic resin-containing member used as a core material such as an interior material, in order to reinforce the core material. Since it is a sheet used, it can be called an exterior reinforcing sheet.

  The exterior reinforcing sheet of the present invention is molded after being laminated on a thermoplastic resin-containing member, and has a function of reinforcing the thermoplastic resin-containing member after molding. In the present invention, the exterior reinforcing sheet is preferably used for applications that are formed after being disposed on the surface layer of the thermoplastic resin-containing member, but may itself form a sheet-like material in a single layer. And it may be used for the use bonded by core materials other than a thermoplastic resin containing member.

Content of a binder component should just be 25 mass% or less with respect to the total mass of the sheet | seat for exterior reinforcement. The content of the binder component is preferably 20% by mass or less, more preferably 18% by mass or less, and even more preferably 15% by mass or less. In addition, it is preferable that the lower limit of content of a binder component is 0.1 mass%.
By making content of a binder component into the said range, adhesiveness with the thermoplastic resin containing member after shaping | molding can be improved. Thereby, the mechanical strength represented by the bending strength etc. of a molded object can be raised.
Moreover, the surface texture of the molded object which has the sheet | seat for exterior reinforcement on the surface can be improved by making content of a binder component into the said range. Here, the good surface texture means that the tactile sensation when touching the surface of the molded body is flexible. Specifically, the tingling sensation and the sensation of the surface (stiff) are reduced. It means being.

  In the exterior reinforcing sheet of the present invention, the content of the inorganic reinforcing fiber is preferably 10% by mass or more and 90% by mass or less, and more preferably 20% by mass or more with respect to the total mass of the inorganic reinforcing fiber and the natural pulp fiber. More preferably, it is 80 mass% or less, More preferably, it is 30 mass% or more and 70 mass% or less. The content of the natural pulp fiber is preferably 10% by mass or more and 90% by mass or less, and preferably 20% by mass or more and 80% by mass or less, with respect to the total mass of the inorganic reinforcing fiber and the natural pulp fiber. More preferably, it is 30 mass% or more and 70 mass% or less. Thus, the intensity | strength of a molded object can be raised more effectively by making mass ratio of an inorganic reinforcement fiber and a natural pulp fiber into the said range. Moreover, the surface texture of a molded object can be improved more effectively by making mass ratio of an inorganic reinforcement fiber and a natural pulp fiber into the said range.

  The total content of inorganic reinforcing fibers and natural pulp fibers is preferably 60% by mass or more, more preferably 70% by mass or more, and more preferably 80% by mass with respect to the total mass of the exterior reinforcing sheet. More preferably, it is more preferably 85% by mass or more. By setting the total content of inorganic reinforcing fibers and natural pulp fibers within the above range, the strength of the molded body can be increased more effectively, and the surface texture of the molded body can be further increased.

The basis weight of the exterior reinforcing sheet of the present invention is preferably 10 g / m ² or more and 120 g / m ² or less, more preferably 12 g / m ² or more and 110 g / m ² or less, and 15 g / m ² or more. More preferably, it is 100 g / m ² or less, and particularly preferably 15 g / m ² or more and 60 g / m ² or less. By setting the basis weight of the exterior reinforcing sheet within the above range, the adhesiveness with the thermoplastic resin-containing member and the like can be more effectively enhanced when the molded body is formed. Thereby, the molded object which has the outstanding intensity | strength can be obtained. Furthermore, by setting the basis weight of the exterior reinforcing sheet within the above range, the thermoplastic resin-containing member can be effectively concealed, and design properties can be exhibited.

Density of the outer reinforcing sheet of the present invention is more it is preferably at most 0.03 g / cm ³ or more 0.9 g / cm ^3, it is 0.05 g / cm ³ or more 0.8 g / cm ³ or less Preferably, it is 0.1 g / cm ³ or more and 0.6 g / cm ³ or less. By setting the density of the exterior reinforcing sheet within the above range, the strength of the exterior reinforcing sheet itself can be increased, and when the molded body is formed, the strength of the molded body can be increased.

  The exterior reinforcing sheet of the present invention is preferably a single layer sheet containing inorganic reinforcing fibers, natural pulp fibers, and a binder component in the same layer. In the exterior reinforcing sheet, the inorganic reinforcing fibers and the natural pulp fibers are preferably mixed uniformly. Here, that the inorganic reinforcing fiber and the natural pulp fiber are uniformly mixed refers to a state in which 50% or more of the inorganic reinforcing fibers are in contact with the natural pulp fiber.

(Inorganic reinforcing fiber)
Examples of inorganic reinforcing fibers include carbon fibers and glass fibers. Among these, glass fibers are preferably used as the inorganic reinforcing fibers.

  The fiber diameter of the inorganic reinforcing fiber is preferably 3 μm or more and 15 μm or less, and preferably 3 μm or more and 13 μm or less. Here, the fiber diameter of the inorganic reinforcing fiber is a number average fiber diameter. In this specification, the number average fiber diameter is an average value of fiber diameters obtained by measuring the fiber diameters of 100 fibers. By setting the fiber diameter of the inorganic reinforcing fiber within the above range, the surface texture of the molded body having the exterior reinforcing sheet on the surface can be improved.

  The fiber length of the inorganic reinforcing fiber is preferably 3 mm or more and 100 mm or less, more preferably 3 mm or more and 50 mm or less, further preferably 3 mm or more and 35 mm or less, and particularly preferably 3 mm or more and 20 mm or less. . Here, the fiber length of the inorganic reinforcing fiber is a mass average fiber length, and in this specification, the mass average fiber length is an average value of fiber lengths measured for 100 fibers. By setting the fiber length of the inorganic reinforcing fiber within the above range, the defibration of the inorganic reinforcing fiber can be promoted, and the proportion of the inorganic reinforcing fiber made into a single fiber can be increased. Thereby, the surface texture of the molded object which has the sheet | seat for exterior reinforcement on the surface can be improved. Furthermore, the strength of the exterior reinforcing sheet itself and the strength of the molded body can be increased.

  The inorganic reinforcing fiber is preferably chopped strand cut to a length within the above-described range. By virtue of such a form, the glass fiber can be uniformly dispersed in the exterior reinforcing sheet.

  The content of the inorganic reinforcing fibers is preferably 10% by mass or more and 90% by mass or less, more preferably 20% by mass or more and 80% by mass or less, and more preferably 20% by mass with respect to the total mass of the exterior reinforcing sheet. % To 75% by mass, more preferably 20% to 70% by mass. By setting the content of the inorganic reinforcing fiber within the above range, the thermoplastic resin-containing member can be reinforced more effectively. Furthermore, the strength of the exterior reinforcing sheet itself can be increased, and the surface texture can be improved.

(Glass fiber)
The inorganic reinforcing fiber is preferably glass fiber. As the glass fiber used in the present invention, filaments are obtained by melt spinning glass such as E glass (Electrical glass), C glass (Chemical glass), A glass (Alkali glass), S glass (High strength glass), and alkali-resistant glass. And the like in the form of a fiber.

  The glass fiber may be round glass or flat glass. Here, the round glass is a fiber having a substantially circular cross-sectional shape. In addition, the cross-sectional shape of a fiber means the shape of the cut surface of a perpendicular direction with respect to the length direction of glass fiber. The flat glass is one in which the cross-sectional shape of the fiber is flat (unshaped) and is not substantially circular. Specifically, the flat shape refers to a shape in which the cross-sectional shape of the fiber has a major axis defined by the maximum length passing through the center point and a minor axis defined by the minimum length passing through the center point. Examples of the flat shape include gourd type, eyebrows type, oval type, and elliptical type.

(Carbon fiber)
The inorganic reinforcing fiber may be a carbon fiber. As the carbon fibers, carbon fibers such as polyacrylonitrile (PAN), petroleum / coal pitch, rayon, and lignin can be used. These carbon fibers may be used alone or in combination of two or more. Of these carbon fibers, polyacrylonitrile (PAN) -based carbon fibers are preferably used from the viewpoint of productivity and mechanical properties on an industrial scale.

(Natural pulp fiber)
Examples of the pulp constituting the natural pulp fiber include wood pulp, non-wood pulp, and deinked pulp. Examples of wood pulp include hardwood kraft pulp (LBKP), softwood kraft pulp (NBKP), sulfite pulp (SP), dissolved pulp (DP), soda pulp (AP), unbleached kraft pulp (UKP), oxygen bleached craft Chemical pulps such as pulp (OKP) are listed. Moreover, semichemical pulps, such as a semichemical pulp (SCP) and a chemiground wood pulp (CGP), mechanical pulps, such as a groundwood pulp (GP) and a thermomechanical pulp (TMP, BCTMP), etc. are mentioned. Non-wood pulp includes cotton pulp such as cotton linter and cotton lint, non-wood pulp such as hemp, straw, bagasse, bamboo, corn, cellulose, chitin, chitosan and the like isolated from sea squirts and seaweeds. Examples of deinked pulp include deinked pulp made from waste paper. One kind of natural pulp described above as the natural pulp fiber may be used alone, or two or more kinds may be used in combination.
Among the above-mentioned natural pulps, wood pulp containing cellulose can be preferably used in terms of easy availability, and softwood kraft pulp (NBKP) can be more preferably used.

  The Canadian standard freeness (CSF) of the natural pulp fiber is preferably 300 ml or more and 800 ml or less, more preferably 300 ml or more and 700 ml or less, and further preferably 350 ml or more and 650 ml or less. Here, Canadian Standard Freeness is a freeness measured by a Canadian standard freeness tester in accordance with JIS P 8121 after the sample is disaggregated in accordance with JIS P 8220. Is the value of By setting the Canadian Standard Freeness of the natural pulp fibers within the above range, the natural pulp fibers are sufficiently entangled, and the natural pulp fibers can be effectively prevented from falling off the exterior reinforcing sheet. Moreover, since the thermoplastic resin contained in the thermoplastic resin-containing member can be easily fitted into the exterior reinforcing sheet, the adhesion between the thermoplastic resin-containing member and the exterior reinforcing sheet can be more effectively increased in the molded body. .

  The content of natural pulp fiber is preferably 10% by mass or more and 90% by mass or less, more preferably 20% by mass or more and 80% by mass or less, and more preferably 25% by mass with respect to the total mass of the exterior reinforcing sheet. The content is more preferably 80% by mass or less, and particularly preferably 30% by mass or more and 80% by mass or less. By making the content of natural pulp fibers within the above range, the surface texture of the molded body having the exterior reinforcing sheet on the surface while enhancing the strength of the exterior reinforcing sheet itself and reinforcing the thermoplastic resin-containing member. Can be improved more effectively. Furthermore, the adhesion between the exterior reinforcing sheet and the thermoplastic resin-containing member is also improved.

(Binder component)
The exterior reinforcing sheet of the present invention includes a binder component. The binder component is a binding component present at the contact point of inorganic reinforcing fiber or natural pulp fiber. Although the shape of a binder component is not specifically limited, For example, it can be set as a particle shape or a fiber shape. Further, the binder component may be used in a state dispersed in an aqueous solution or an emulsion.

  The content of the binder component is 25% by mass or less with respect to the total mass of the exterior reinforcing sheet. The content of the binder component is more preferably 20% by mass or less, further preferably 18% by mass or less, and particularly preferably 15% by mass or less. In addition, it is preferable that the lower limit of content of a binder component is 0.1 mass%. By making content of a binder component into the said range, adhesiveness with a thermoplastic resin containing member can be improved, and the bending strength of the molded object containing a thermoplastic resin containing member and the sheet | seat for exterior reinforcement can be improved. Moreover, the surface texture of the molded object which has the sheet | seat for exterior reinforcement on the surface can be improved by making content of a binder component into the said range.

  Examples of the binder component include polyester resins such as polyethylene terephthalate and modified polyethylene terephthalate, acrylic resins, styrene- (meth) acrylic acid ester copolymer resins, urethane resins, polyvinyl alcohol (PVA) resins, various starches, cellulose derivatives, Sodium polyacrylate, polyacrylamide, polyvinylpyrrolidone, acrylamide-acrylic acid ester-methacrylic acid ester copolymer, styrene-maleic anhydride copolymer alkali salt, isobutylene-maleic anhydride copolymer alkali salt, polyvinyl acetate resin Styrene-butadiene copolymer, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, styrene-butadiene- (meth) acrylic acid ester copolymer, and the like.Among these, as the binder component, it is preferable to use at least one selected from an acrylic resin and a polyvinyl alcohol (PVA) resin.

  The acrylic resin used as the binder component may be an acrylic fiber, an emulsion containing an acrylic resin, or a solution in which an acrylic resin is dispersed in water. Especially, in this invention, it is preferable to use an acrylic resin emulsion. By applying such an aqueous solution or emulsion by a method such as spraying or impregnation, an exterior reinforcing sheet containing a binder component can be obtained.

  As the polyvinyl alcohol (PVA) resin, both a fibrous polyvinyl alcohol (PVA) resin and a granular polyvinyl alcohol (PVA) resin can be preferably used. Alternatively, a solution of polyvinyl alcohol (PVA) can be applied by spraying or impregnation.

  When the shape of the binder component is a fiber shape, the fiber length of the binder fiber is preferably 3 mm or more, more preferably 10 mm or more, further preferably 15 mm or more, and particularly preferably 20 mm or more. preferable. In addition, the fiber length of a binder fiber can also be 50 mm or more. The fiber length of the binder fiber is preferably 150 mm or less, more preferably 100 mm or less, and further preferably 75 mm or less. In addition, in this specification, the fiber length of a binder fiber is a mass weighted average fiber length, and is the average value of the fiber length measured about 100 fibers.

  Moreover, when the shape of a binder component is a fiber shape, it is preferable that the fiber diameter of a binder fiber is 3 micrometers or more and 25 micrometers or less. In addition, in this specification, the fiber diameter of a binder fiber is a number average fiber diameter, and is an average value of the fiber diameter which measured the fiber diameter of 100 fibers.

  When the shape of the binder component is a particle shape, the average primary particle diameter of the binder particles is preferably 3 μm or more and 7000 μm or less, more preferably 30 μm or more and 3000 μm or less, and further preferably 100 μm or more and 1000 μm or less. preferable. When the binder particles are not spherical, the average primary particle diameter of the binder particles is determined by calculating the projected area of the particles with a transmission electron micrograph, and the diameter of a circle having the same area is defined as the average primary particle diameter. By making the average primary particle diameter of the binder particles within the above range, it is possible to make a net, and it is possible to obtain an exterior reinforcing sheet by a wet papermaking method.

(Other ingredients)
The exterior reinforcing sheet may include thermoplastic fibers other than the binder component described above. However, when the exterior reinforcing sheet contains thermoplastic fibers other than the binder component described above, the total content of the binder component and the thermoplastic resin is preferably 25% by mass or less. Examples of the thermoplastic fiber other than the binder component described above include polycarbonate (PC), polyamide, and polypropylene.

(Method for manufacturing exterior reinforcing sheet)
It is preferable that the manufacturing process of the sheet | seat for exterior reinforcement | strengthening of this invention includes the process of wet-paper-making the slurry which mixed the inorganic reinforcement fiber, the natural pulp fiber, and the binder component. Examples of the paper machine used in this wet paper making process include a continuous paper machine such as a long-mesh type, a circular net type, and an inclined type, and a multi-layered paper machine combining these. In the paper making process, known paper making such as hand making may be performed.

In the papermaking process, a slurry containing inorganic reinforcing fibers, natural pulp fibers, and a binder component is filtered on a wire and dehydrated to obtain a wet paper sheet. obtain.
Although the density | concentration of a slurry is not specifically limited, 0.05 mass% or more and 5 mass% or less are preferable. In the dehydration step, a dehydration method generally used in paper manufacture can be employed. For example, a method of dehydrating with a long net, a circular net, an inclined wire, etc. and then dewatering with a roll press is preferable. Moreover, as a drying method, methods, such as a cylinder dryer, a Yankee dryer, hot air drying, a near-infrared heater, an infrared heater, are preferable, for example.

  In the manufacturing process of the exterior reinforcing sheet of the present invention, it is also preferable to provide a step of spray coating or impregnating a binder component on the sheet obtained after the paper making process. For example, a fibrous binder component is added to a mixed slurry of inorganic reinforcing fibers and natural pulp fibers to make paper, and binder components other than fibrous components are added after obtaining a sheet as an aqueous solution or emulsion. Can do. In addition, it is preferable to provide a drying process after the spray application process of a binder component. In this way, by adding the binder component of the aqueous solution or emulsion, it is possible to suppress the scattering, fluffing, and dropping of the surface fibers of the exterior reinforcing sheet, and it is possible to obtain an exterior reinforcing sheet having excellent handling properties. . Furthermore, a molded body having excellent strength can be molded.

(Molded body)
The present invention also relates to a molded body formed by disposing the above-described exterior reinforcing sheet on at least one surface of a thermoplastic resin-containing member. In the molded body of the present invention, since the thermoplastic resin-containing member is used as the core and the exterior reinforcing sheet having the above-described configuration is included, the molded exterior reinforcing sheet and the thermoplastic resin are contained. The adhesion of the member can be improved. For this reason, a molded object can exhibit the outstanding intensity | strength.
The exterior reinforcing sheet is preferably arranged so as to cover the surface layer of the molded body. Such a molded body is excellent in surface texture. The exterior reinforcing sheet may be disposed and molded on at least one surface of the thermoplastic resin-containing member, but may be disposed and molded on both surfaces of the thermoplastic resin-containing member.

  Examples of the thermoplastic resin contained in the thermoplastic resin-containing member include polyurethane resin, polyisocyanate resin, phenol resin, vinyl chloride resin, polyethylene resin, polystyrene resin, urea resin, and polypropylene resin.

  The thermoplastic resin-containing member may be a member made of the above resin, but may be a composite material containing reinforcing fibers in addition to the above resin. For example, it may be a composite material including at least one fiber selected from glass fiber and carbon fiber and a thermoplastic resin. In this case, the content of the thermoplastic resin is preferably 40% by mass or more, and more preferably 50% by mass or more with respect to the total mass of the thermoplastic resin-containing member.

  The thermoplastic resin-containing member may be a foamable member. In this case, it is preferable to add a foaming agent to the thermoplastic resin-containing member in advance. For example, by adding a pyrolytic foaming agent or the like, the thermoplastic resin-containing member can be made into a foam when the formed body is formed. Alternatively, only the core material may be heated and foamed in advance, and then bonded to the surface material. In addition, when the thermoplastic resin-containing member is a foamable member, a member obtained by injection foam molding can also be preferably used. By using the thermoplastic resin-containing member as a foamable member, the molded body can be further reduced in weight.

  Since the molded body of the present invention has excellent strength and surface texture, it is preferably used as a vehicle interior material or an interior interior material. Among these, it is preferably used as an automobile interior member. The molded body of the present invention can be reduced in weight by using the core material as the thermoplastic resin-containing member, and by using such a molded body as an automobile interior member, it can contribute to reduction in fuel consumption. it can.

Bending elasticity gradient of the shaped body of the present invention is preferably 25N / cm / kg / m ² or more, more preferably 30N / cm / kg / m ² or more, 35N / cm / kg / m 2 More preferably, it is more preferably 40 N / cm / kg / m ² or more. By setting the bending elastic gradient of the molded body within the above range, the rigidity of the molded body can be increased, and unintentional breaking during use can be suppressed.
The bending elastic gradient of the molded body is calculated using an equation for calculating the bending elastic modulus by performing a bending test according to JIS K 7203, using a molded body having a width of 50 mm and a length of 150 mm, setting the distance between supporting points to 100 mm. .

(Method for producing molded body)
When the molded body is molded, an exterior reinforcing sheet can be laminated on the surface of the thermoplastic resin-containing member and processed into an arbitrary shape according to the target shape or molding method. In the manufacturing process of a molded object, it is preferable to heat-press-mold the exterior reinforcing sheet at a temperature at which the binder component flows and the inorganic reinforcing fiber and natural pulp fiber are not thermally deteriorated. Specifically, the heating temperature is preferably 150 ° C. or higher and 600 ° C. or lower, preferably 150 ° C. or higher and 300 ° C. or lower, and more preferably 150 ° C. or higher and 250 ° C. or lower. By setting it as such a temperature range, the thermal deterioration and discoloration by heat of natural pulp can be suppressed. Moreover, as a pressure, 0.5 MPa or more and 20 MPa or less are preferable.

  As a method of heat and pressure molding, among various methods of heat and pressure molding, an autoclave method and a die press method that are often used when producing a molded body member such as a large aircraft are preferably mentioned. . From the viewpoint of energy consumption in equipment and molding process, simplification of jigs and auxiliary materials to be used, molding pressure, and flexibility of temperature, a mold press that performs molding using a metal mold It is preferable to use methods, and these can be selected depending on the application.

For the die pressing method, a heat and cool method or a stamping molding method can be employed. In the heat and cool method, a stack in which exterior reinforcing sheets are laminated on the surface of a thermoplastic resin-containing member is placed in a mold in advance, and pressure and heating are performed together with mold clamping, and then mold clamping is performed. In this method, the mold is cooled by cooling the mold. In the stamping molding method, the stack is heated in advance by a heating device such as a far-infrared heater, a heating plate, a high-temperature oven, dielectric heating, and the thermoplastic resin is melted and softened and placed inside the molded body mold. Next, the mold is closed, the mold is clamped, and then the pressure is cooled. Moreover, when the temperature at the time of shaping | molding is comparatively low, such as when obtaining a low density molded object, a hot press method can also be employ | adopted.
In the present invention, it is preferable to heat and pressure mold a stack in which exterior reinforcing sheets are laminated on both surfaces of the thermoplastic resin-containing member. By using such a stack, a mold after heat and pressure molding is used. Release property can be improved. For this reason, even if it does not perform a mold release process to a metal mold | die, a molded object can be released easily and it is suppressed that the inside of a metal mold | die is contaminated with resin.

  Molds for molding are roughly classified into two types, one is a sealed mold used for casting or injection molding, and the other is an open mold used for press molding or forging. An open mold is preferable from the viewpoint of eliminating decomposition gas and mixed air from the mold during molding, but in order to suppress excessive resin flow, the number of open parts should be reduced as much as possible during the molding process. It is also preferable to adopt a shape that suppresses outflow from the mold.

  Furthermore, the metal mold | die which has at least 1 type selected from a punching mechanism and a tapping mechanism can be used for a metal mold | die. It is also possible to punch the formed body continuously after hot pressing by means such as using a two-stage press mechanism. In addition, depending on the purpose of use, the molded body can be provided with a pattern for the purpose of reinforcing strength such as ribs and bosses, forming projections and screw holes for processing, and imparting design properties.

  Moreover, in the manufacturing process of a molded object, it is also possible to adhere | attach a more complicated shape member by outsert molding or insert molding simultaneously with shaping | molding a molded object, or after shaping | molding.

(Stack)
The present invention may relate to a stack in which the above-described exterior reinforcing sheets are laminated on the surface of a thermoplastic resin-containing member. The exterior reinforcing sheet and the thermoplastic resin-containing member are preferably integrally molded by heat and pressure molding, but the stacked body obtained by bonding the exterior reinforcing sheet and the thermoplastic resin-containing member with an adhesive or the like is heated. You may press-mold. That is, in the present invention, the stack is formed by laminating the exterior reinforcing sheet on the surface of the thermoplastic resin-containing member and the exterior reinforcing sheet on the surface of the thermoplastic resin-containing member via an adhesive layer or the like. Layered embodiments are included.
In the present invention, such a stack is subjected to heat and pressure molding, so that the mold releasability can be improved and the production efficiency of the molded body can be increased.

  In addition, the stack may be obtained by bonding the exterior reinforcing sheet and the thermoplastic resin-containing member by heating and pressing, and then bonding them with an adhesive or the like. The stacked body after bonding may be further integrally formed by heating and pressing.

  The features of the present invention will be described more specifically with reference to examples and comparative examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

Example 1
Natural pulp (manufactured by CENIBRA, NBKP pulp sheet, moisture 20%) was poured into water to a concentration of 3.0% by mass, disaggregated for 10 minutes using a disintegrator, and Canadian Standard Standards shown in Table 1 A freeness pulp slurry was obtained. The obtained slurry was diluted with water to a concentration of 0.2% by mass and stirred to obtain a pulp slurry having a uniform concentration.
Next, water is introduced into another container, glass fibers having a fiber diameter and fiber length shown in Table 1 (CS06DAGP195, manufactured by Owens Corning Co., Ltd.) are added, and Rakkal AL is added to the mass of the glass fiber as a dispersant. It added so that it might become 1 mass%. Water was added again to adjust the glass fiber concentration to 0.2% by mass. The obtained glass fiber slurry was stirred for 15 minutes using an agitator (three-one motor) to obtain a uniformly dispersed glass fiber slurry.
And each slurry was mixed so that the compounding ratio of a natural pulp fiber and glass fiber might become the ratio of Table 1, and the glass fiber containing pulp slurry was obtained.

  A fibrous PVA binder (VPB105-1) was added to the glass fiber-containing pulp slurry so as to have a blending ratio shown in Table 1, and the mixture was stirred and mixed uniformly. The obtained slurry was formed into a sheet with a hand-made machine manufactured by Kumagai Riki Kogyo Co., Ltd. having an internal size of 25 cm × 25 cm, and dried using a ferro-type dryer having a temperature of 110 ° C. The basis weight of the dried sheet was as shown in Table 1. In the obtained sheet, a 1.0% by mass concentration of acrylic resin emulsion (manufactured by Dainippon Ink & Chemicals, Inc., GM-1000) is added so that the ratio to the total mass of the exterior reinforcing sheet is as shown in Table 1. Spray added. Then, it dried with a 110 degreeC hot air dryer, and obtained the sheet | seat for exterior reinforcement.

(Examples 2 to 4)
An exterior reinforcing sheet was obtained in the same manner as in Example 1 except that the basis weight was as shown in Table 1.

(Examples 5-7)
An exterior reinforcing sheet was obtained in the same manner as in Example 2 except that the addition amounts of glass fiber, natural pulp fiber and binder component were changed as shown in Table 1.

(Example 8)
An exterior reinforcing sheet was obtained in the same manner as in Example 2 except that the fiber length and fiber diameter of the glass fiber were as shown in Table 1.

Example 9
Example 2 with the exception that natural pulp fiber was disaggregated with a disintegrator and then treated with a single disc refiner for testing (manufactured by Kumagai Riki Co., Ltd.), and Canadian Standard Freeness was as shown in Table 1. Similarly, an exterior reinforcing sheet was obtained.

(Comparative Examples 1-3)
An exterior reinforcing sheet was obtained in the same manner as in Example 2 except that the addition amounts of glass fiber, natural pulp fiber and binder component were changed as shown in Table 1.

<Bonding with thermoplastic resin-containing member (core material)>
As a thermoplastic resin-containing member (core material), a sheet having a basis weight of 800 g / m ² mixed with natural pulp, PP resin fiber, and PP / PE core-sheath binder resin fiber (compounding ratio: natural pulp / PP resin / PP / PE) Core-sheath binder resin fiber = 40/50/10) was prepared. The core material and the exterior reinforcement sheet were cut into rectangles each having a width of 60 mm and a length of 160 mm, and the exterior reinforcement sheets were disposed on both surfaces of the core material, and pressed at a press pressure of 5 MPa and a press temperature of 240 ° C. for 40 seconds. . Then, it cooled and took out at 70 degreeC and the molded object which has a sheet | seat for exterior reinforcement on both surfaces was created. Four sides of the obtained molded body were trimmed by 5 mm each to obtain a molded body having a width of 50 mm and a length of 150 mm.

(Evaluation)
<Adhesiveness>
As shown in FIG. 1, the adhesive tape 50 is affixed to the end portion of the exterior reinforcing sheet 10 of the molded body 40, and the adhesive tape 50 is lifted upward so that the molded body 40 and the molded body 40 are in an approximately 90 ° direction. The exterior reinforcing sheet 10 was peeled off from the member (core material) 20 in the direction of the arrow. The adhesive range of the adhesive tape 50 was 10 mm from the end. The state of the core material 20 after being peeled off was observed and evaluated in four stages A to D as follows. In addition, A has the best adhesiveness, D has the worst adhesiveness, and C evaluation or more was made into the pass level.
A: Natural pulp fibers adhere to the entire surface of the core material.
B: The portion where the natural pulp fiber is not attached is less than 5% of the area of the core material.
C: The portion where the natural pulp fiber is not attached is 5% or more and less than 30% of the core material.
D: The part where the natural pulp fiber is not attached is 30% or more of the area of the core material.

<Hand feeling>
Ten adults who did not touch the inorganic fiber-containing non-woven fabric such as glass fiber non-woven fabric in daily life and daily work were used as subjects, and the hand feeling was evaluated as follows.
<< Evaluation method >>
(1) 100% natural pulp fiber filter paper (manufactured by Advantech, FILTER PAPER 5C) is gently stroked 3 times with the index finger.
(2) Stroke the surface of the compact three times in the same manner.
(3) For the tingling sensation, the following three stages are evaluated: Exhibit A: The molded body does not feel tingling at all compared to the filter paper.
Otsu: The compact feels slightly tingling compared to the filter paper.
丙: The molded product has a clear tingling feeling compared to the filter paper.
(4) The obtained results were tabulated and evaluated in four stages A to D as follows. In addition, B evaluation or more was made into the pass level.
A: Eight or more people judged to be Class A, 2 or less who were judged to be Class B, 0 who were judged to be Samurai B: Three or more people who were judged to be Class A, who were judged to be Class B 7 or less, 0 people judged to be niece C: 1 to 2 people judged to be niece D: 3 or more people judged to be niece

<Bending elastic gradient per unit basis weight (per kg / m ² )>
Using the above-mentioned molded body having a width of 50 mm and a length of 150 mm, a bending test according to JIS K 7203 is performed with the distance between fulcrums of 100 mm, and the value represented by the bending elastic gradient is calculated in the equation for calculating the bending elastic modulus. calculated, unit weight per unit area (kg / m ²⁾ per bending elastic gradient (N / cm / kg / m 2) was calculated.

  The evaluation results are shown in Table 1. In the molded body in which the exterior reinforcing sheet obtained in the examples was bonded, the adhesiveness, the bending elastic gradient, and the touch feeling were good. On the other hand, in Comparative Example 1 containing no glass fiber, the bending elastic gradient was clearly inferior. Moreover, the comparative example 2 which does not contain a natural pulp fiber was especially bad in a touch feeling, and was inferior to adhesiveness. In Comparative Example 3 in which the amount of the binder was large, the PP resin of the thermoplastic resin-containing member was difficult to fit, resulting in poor adhesion.

10 Exterior reinforcement sheet 20 Thermoplastic resin-containing member (core material)
40 Molded body 50 Adhesive tape

Claims (9)

An exterior reinforcing sheet containing inorganic reinforcing fibers, natural pulp fibers, and a binder component,
The content of the binder component state, and are more than 25% by weight relative to the total weight of the outer reinforcing sheet,
The binder component includes an acrylic resin, and the acrylic resin is spray-coated on the exterior reinforcing sheet.   2. The exterior reinforcing sheet according to claim 1, wherein a content of the natural pulp fiber is 20% by mass or more and 80% by mass or less with respect to a total mass of the inorganic reinforcing fiber and the natural pulp fiber.   3. The exterior reinforcing sheet according to claim 1, wherein a content of the natural pulp fiber is 15% by mass or more based on a total mass of the exterior reinforcing sheet. The sheet for exterior reinforcement according to any one of claims 1 to 3, wherein the basis weight is 10 g / m ² or more and 120 g / m ² or less. The exterior reinforcing sheet according to any one of claims 1 to 4, wherein the density is 0.03 g / cm ³ or more and 0.9 g / cm ³ or less.   The fiber diameter of the said inorganic reinforcement fiber is 3 micrometers or more and 15 micrometers or less, The sheet | seat for exterior reinforcement of any one of Claims 1-5.   The exterior reinforcing sheet according to any one of claims 1 to 6, wherein a fiber length of the inorganic reinforcing fiber is 3 mm or more and 35 mm or less.   The molded object formed by arrange | positioning the sheet | seat for exterior reinforcement of any one of Claims 1-7 to at least one surface of a thermoplastic resin containing member.   The molded product according to claim 8, which is used as an interior member for automobiles.

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