JP2011207162A - Molding sheet and sheet molding using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding sheet excellent in moldable in press work and a sheet molding exhibiting light weight while fully responding to environmental issues which is molded by foam-molding and press-molding the molding sheet.SOLUTION: In a molding sheet having surface, intermediate and back layers and containing a fibrous material and a foaming agent, the intermediate layer contains a natural fiber, a thermoplastic synthetic fiber and a non-thermoplastic chemical fiber as fibrous materials, the surface and back layers contain the natural fiber and the thermoplastic synthetic fiber as the fibrous materials, and the content of foaming agent is smaller than 5 mass% with respect to the fibrous materials, respectively, in the surface layer and back layer.

Description

  The present invention relates to a molding sheet used for, for example, automobile interior ceiling materials and building materials, and a sheet-like molded body molded by foaming and pressing the molding sheet.

  In general, ceiling interior materials and building materials for automobiles are required to have heat insulation properties, sound absorption properties, rigidity, dimensional stability, and the like. On the other hand, in recent years, for ceiling interior materials and building materials for automobiles, in addition to such requirements for heat insulation, lightness, improved formability, workability in the manufacturing process, thermal recycling, industrial Environmental considerations such as waste reduction are strongly demanded.

As a conventional automotive ceiling interior material, for example, an automotive molded ceiling material has been developed in which glass chopped strand mats are bonded to both surfaces of a polyurethane foam sheet with a binder (see Japanese Patent No. 4026455, etc.). This glass chopped strand mat is obtained by bonding glass chopped strands via an adhesive, has a basis weight of 80 g / m ^{2 to} 200 g / m ² , and has an ignition loss of 10% by mass measured based on JIS-R3420. -25% by weight.

  However, although the above-mentioned conventional molded ceiling material for automobiles is excellent in rigidity, dimensional stability, heat insulation, etc., since glass fiber is used as a material, weight reduction, improvement in formability in press processing, thermal recycling, etc. The environmental problems cannot be cleared sufficiently.

Japanese Patent No. 4026455

  The present invention has been made in view of these disadvantages, and has excellent heat insulating properties, sound absorption properties, etc., yet is lightweight, has a high elongation rate, excellent formability, and can be thermally recycled. The object is to provide a sheet-like molded body obtained by foaming and pressing the sheet for molding and the molding sheet.

The invention made to solve the above problems is
A sheet for molding comprising a surface layer, an intermediate layer and a back layer, containing a fiber material and a foaming agent,
The intermediate layer contains natural fibers, thermoplastic synthetic fibers and non-thermoplastic chemical fibers as fiber materials,
The surface layer and the back layer contain natural fibers and thermoplastic synthetic fibers as fiber materials,
Content of the foaming agent with respect to the fiber raw material in each layer of the said surface layer and back layer is less than 5 mass%, It is characterized by the above-mentioned.

The molding sheet has the following actions.
(A) Since the intermediate layer contains natural fibers, it can sufficiently cope with environmental problems such as thermal recycling while improving the lightness of the sheet-like molded body using the molding sheet and the moldability by press working. be able to.
(B) Since the intermediate layer contains thermoplastic synthetic fibers, the sheet-like molded body using the molding sheet is imparted with good sound absorbency and the like and has good moldability by press working. be able to.
(C) Since the intermediate layer contains non-thermoplastic chemical fibers, the sheet-like molded body using the molding sheet can be imparted with lightness while imparting high heat insulation properties, etc. It is possible to effectively prevent breakage and delamination of the sheet-like formed body using the forming sheet and improve the formability by press working.
(D) The intermediate layer contains a foaming agent, so that the fiber spacing between the fiber materials constituting the intermediate layer is expanded, and the heat insulating property of the sheet-like molded body using the molding sheet is improved. Can achieve a sufficient weight reduction.
(E) As the surface layer and the back layer contain natural fibers, as in the case of the intermediate layer described above, the lightness of the sheet-shaped molded body using the molding sheet and the compatibility with environmental problems are improved. In addition, it is possible to prevent or reduce the falling off of the foaming agent from the intermediate layer, and as a result, it is possible to ensure the formability by pressing.
(F) The surface layer and the back layer contain thermoplastic synthetic fibers, thereby imparting high sound-absorbing properties and the like to the sheet-like molded body using the molding sheet as in the case of the intermediate layer described above. In addition, good stretchability is imparted to the outer surfaces of both surfaces of the molding sheet, and as a result, the moldability by press working can be further improved.
(G) When the content of the foaming agent with respect to the fiber material in each of the surface layer and the back layer is less than 5% by mass, preferably less than 3% by mass, and most preferably unmixed, the molding sheet is processed into a molded body. Even under heating, the foaming agent can exhibit high stretchability without substantially expanding the fiber spacing of the fiber material, and is excellent in moldability by press working.

  Here, the “non-thermoplastic chemical fiber” means a chemical fiber having characteristics similar to those of a thermoplastic synthetic fiber, but having no melting point at a temperature lower than the thermal decomposition temperature.

  In the intermediate layer, the blending amount of the natural fiber with respect to the fiber material is 10% by weight or more and 80% by weight or less, the blending amount of the thermoplastic synthetic fiber is 10% by weight or more and 40% by weight or less, and the blending of the non-thermoplastic chemical fiber. The amount is preferably 1% by mass or more and 50% by mass or less. Thus, in an intermediate | middle layer, it is high with respect to the sheet-like molded object using the said sheet | seat by making each compounding quantity of the natural fiber with respect to a fiber raw material, a thermoplastic synthetic fiber, and a non-thermoplastic chemical fiber into the said range. While providing sound absorption and heat insulation in a well-balanced manner, light weight and formability by press working can be realized in a well-balanced manner.

  In each of the surface layer and the back layer, the mass ratio of natural fiber to thermoplastic synthetic fiber is preferably 10/90 or more and 80/20 or less. Thus, in each surface layer and back layer, by making the mass ratio of the natural fiber and the thermoplastic synthetic fiber within the above range, the sheet-shaped molded body using the molding sheet has high lightness and sound absorption. The formability by press working can be most reliably realized while imparting good properties and the like in a balanced manner.

  It is preferable that the thermoplastic synthetic fibers of the surface layer and the back layer have a core-sheath structure, and the melting point of the sheath part of the core-sheath structure is lower than the melting point of the core part. Thus, the melting point of the sheath part of the core-sheath structure of the thermoplastic synthetic fiber of the surface layer and the back layer is lower than the melting point of the core part, so that the molding sheet has the low melting point sheath part in the surface layer and the back layer. It is possible to exhibit high stretchability and strength that can withstand press working by softening or melting the core portion prior to heating the core of the molding sheet to bond the fiber materials firmly. Moreover, the high melting point core portion that is difficult to soften or melt under heating of the molded body maintains the bonding strength between the fiber materials, and exhibits higher strength and waist. That is, since each layer of the front layer and the back layer containing the thermoplastic synthetic fiber having such a core-sheath structure is configured to sandwich the intermediate layer, the molding sheet as a whole is particularly excellent in formability by press working. Can be demonstrated. In addition, when the said thermoplastic synthetic fiber is a core-sheath structure, "melting | fusing point of a thermoplastic synthetic fiber" means melting | fusing point of a sheath part.

  The foaming start temperature of the foaming agent is preferably not higher than the melting point of the thermoplastic synthetic fiber. In this way, the foaming start temperature of the foaming agent is not higher than the melting point of the thermoplastic synthetic fiber, so that the thermoplastic synthetic fiber is prevented from melting prior to the foaming start of the foaming agent, and the foaming agent by the melted thermoplastic synthetic fiber Inhibition of foaming can be effectively prevented, and as a result, lightness, heat insulation and the like can be reliably imparted to the sheet-like molded body using the molding sheet.

  Another invention for solving the above problem is a sheet-like molded body formed by foaming and pressing the molding sheet. Since the sheet-like molded article uses the above-described molding sheet, it exhibits particularly good light weight while exhibiting heat insulation and the like, and can sufficiently cope with environmental problems such as thermal recycling. it can.

  As described above, the molding sheet of the present invention has high heat insulation, sound absorption and elongation, and is excellent in press formability. Further, the molding sheet of the present invention is molded by foaming and pressing. The sheet-like molded body exhibits good light weight and can sufficiently cope with environmental problems such as thermal recycling.

It is typical sectional drawing which shows the sheet | seat for shaping | molding which concerns on one Embodiment of this invention. It is typical sectional drawing which shows the sheet-like molded object which concerns on one Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

(Forming sheet)
The molding sheet 1 in FIG. 1 includes an intermediate layer 2, a surface layer 3, and a back layer 4. The molding sheet 1 is formed by multilayer papermaking.

(Middle layer)
The intermediate layer 2 contains natural fibers, thermoplastic synthetic fibers and non-thermoplastic chemical fibers as fiber materials, and further contains a foaming agent. Hereinafter, the components of the intermediate layer 2 will be described in detail.

<Natural fiber>
Natural fiber is a material constituting the intermediate layer 2. By including such natural fibers in the intermediate layer 2, the lightness of the sheet-like molded body using the molding sheet 1 can be improved, and the moldability by press working can be improved. In addition, these natural fibers are easy and safe to handle in the manufacturing process, and are easy to incinerate, so the efficiency of thermal recycling can be improved, and a significant reduction in industrial waste can be realized. It is possible to cope with environmental problems.

  The type of the natural fiber is not particularly limited, and examples thereof include waste paper pulp, chemical pulp, mechanical pulp and the like, and pulps made from sisal hemp, manila hemp, sugar cane, cotton, silk, kenaf, bamboo, etc. Can be mentioned. Among them, it is preferable to use bamboo exhibiting high rigidity, kenaf or manila hemp having high fiber strength. Further, it is more preferable to use the following softwood kraft pulp (softwood bleached kraft pulp, softwood unbleached kraft pulp) that can be easily obtained and processed, has relatively large paper strength, and can impart good strength to the molding sheet 1. .

  As the above-mentioned waste paper pulp, for example, corrugated waste paper, tea waste paper, craft envelope waste paper, flyer waste paper, magazine waste paper, newspaper waste paper, office waste paper, Kami white waste paper, Kent waste paper, structured waste paper, and old paper waste paper, etc. , Disaggregation / deinked waste paper pulp, deinking / bleached waste paper pulp, and the like.

  Examples of the chemical pulp include hardwood bleached kraft pulp (LBKP), softwood bleached kraft pulp (NBKP), hardwood unbleached kraft pulp (LUKP), softwood unbleached kraft pulp (NUKP), hardwood half bleached kraft pulp (LSBKP), Examples include softwood semi-bleached kraft pulp (NSBKP), hardwood sulfite pulp, and softwood sulfite pulp.

  Examples of the mechanical pulp include stone ground pulp (SGP), pressurized stone ground pulp (PGW), refiner ground pulp (RGP), chemi-ground pulp (CGP), thermo grand pulp (TGP), ground pulp (GP), and thermo. Examples include mechanical pulp (TMP), chemisermo mechanical pulp (CTMP), refiner mechanical pulp (RMP), and the like.

  The upper limit of the blending amount of the natural fiber with respect to the fiber material in the mid layer 2 is preferably 80% by mass, and more preferably 75% by mass. Moreover, as a minimum of the compounding quantity of this natural fiber, 10 mass% is preferable and 40 mass% is especially preferable. Thus, by making the compounding quantity of the natural fiber with respect to the fiber material in the intermediate layer 2 into the above range, the moldability of the molding sheet 1 by press working, and the lightness of the sheet-like molded body using the molding sheet 1 Can be demonstrated in a well-balanced manner. In addition, when the blending amount of such natural fibers exceeds the above upper limit, the entanglement between the fiber materials becomes insufficient, and the occurrence of breakage during the production of the molding sheet tends to increase, which tends to make stable production difficult. Moreover, when the blending amount of the natural fiber is less than the above lower limit, the density becomes high, the elongation rate is lowered, and press workability may be lowered.

<Thermoplastic synthetic fiber>
The thermoplastic synthetic fiber is a thermoplastic fiber body contained in the intermediate layer 2 together with the natural fiber. This thermoplastic synthetic fiber does not melt in the state of the molding sheet 1 before processing the molded body, but melts under the heating of the molded body to penetrate between the fibers of the natural fiber, and then cools. Since it solidifies again, it can give high rigidity, dimensional stability, and sound absorption to the sheet-like molded body using the molding sheet 1 and realizes moldability and molding retainability by good pressing. can do.

  The type of the thermoplastic synthetic fiber is not particularly limited. For example, polyolefin fibers such as polyethylene, polypropylene, and copolymerized polypropylene; polyethylene terephthalate (hereinafter sometimes referred to as “PET”), polybutylene terephthalate, and polypropylene terephthalate. Polyester fibers such as polyethylene naphthalate and copolymer polyester; Polyamide fibers such as nylon-4, nylon-6, nylon-46, nylon-66, copolymer nylon; polylactic acid, polybutylene succinate, polyethylene succinate And biodegradable fibers. Above all, it is excellent in adhesiveness by heat melting with natural fibers, and as a result, it improves the rigidity, dimensional stability, sound absorption, and moldability by press working of the sheet-like molded body using the molding sheet 1. It is preferable to use a system fiber. The melting point of the thermoplastic synthetic fiber is preferably equal to or higher than the foaming start temperature of the foamable microcapsule in order to avoid the foaming inhibition of the foamable microcapsule described later.

  As an upper limit of the compounding quantity of the thermoplastic synthetic fiber with respect to the fiber raw material in the intermediate | middle layer 2, 40 mass% is preferable and 25 mass% is more preferable. Moreover, as a minimum of the compounding quantity of this thermoplastic synthetic fiber, 10 mass% is preferable and 15 mass% is more preferable. Thus, by making the compounding quantity of the thermoplastic synthetic fiber with respect to the fiber raw material in the intermediate layer 2 within the above range, the penetration rate of the molten thermoplastic synthetic fiber between the natural fibers is improved, and the molding sheet 1 is formed. While imparting high rigidity, dimensional stability, and sound absorption to the used sheet-shaped molded body in a well-balanced manner, it is possible to improve moldability by pressing. In addition, when the compounding quantity of this thermoplastic synthetic fiber exceeds the said upper limit, the number of natural fibers may reduce and elongation rate may fall. Moreover, when the blending amount of the thermoplastic synthetic fiber is less than the above lower limit, the density tends to increase, the adhesion effect between the fiber materials becomes insufficient, and the occurrence of tearing tends to increase.

  The upper limit of the average fiber length of the thermoplastic synthetic fiber is preferably 5 mm, and more preferably 2 mm. Moreover, as a minimum of the average fiber length of this thermoplastic synthetic fiber, 0.1 mm is preferable and 0.5 mm is more preferable. Thus, by making the average fiber length of the thermoplastic synthetic fiber within the above range, the melting efficiency of the thermoplastic synthetic fiber by heating is improved, and between the fibers of the natural fibers in the sheet-like molded body using the molding sheet 1 Improves the permeability to As a result, the sheet-like molded body using the molding sheet 1 can exhibit high rigidity, dimensional stability, and sound absorption in a balanced manner. In addition, when the average fiber length of this thermoplastic synthetic fiber exceeds the said upper limit, there exists a possibility of inhibiting the foaming agent mentioned later, especially foaming of a foamable microcapsule. Moreover, when the average fiber length of the thermoplastic synthetic fiber is less than the lower limit, the bonding effect between the fiber materials becomes insufficient, and the occurrence of tearing tends to increase.

  The “average fiber length” referred to in the present invention means an average value obtained by weight-weighting the centerline fiber length measured using FiberLab (manufactured by Kajaani).

<Non-thermoplastic chemical fiber>
The non-thermoplastic chemical fiber is contained in the intermediate layer 2 together with the natural fiber and the thermoplastic synthetic fiber, and is a fiber body that is not melted by heating. Such a non-thermoplastic chemical fiber is a natural fiber of a sheet-like molded body using the molding sheet 1 by partially inhibiting hydrogen bonding between the fibers of the natural fiber without melting under heating of the molded body processing. A continuous airway is formed between the fibers of the sheet, and in addition to rigidity, heat insulation, and sound absorption, the sheet-like molded body is lightweight, and the sheet-like molded body is effectively prevented from being broken or delaminated. As a result, the formability by press working can be improved.

  Although it does not specifically limit as a kind of the said non-thermoplastic chemical fiber, For example, regenerated cellulose fibers, such as a vinylon fiber, an acrylic fiber, an aramid fiber, a rayon fiber, etc. are mentioned. Among them, the vinylon fiber having a substantially circular cross-sectional shape perpendicular to the fiber direction can impart high rigidity, heat insulation, sound absorption, and lightness to the sheet-like molded body using the molding sheet 1. Therefore, it is preferable.

  As an upper limit of the compounding quantity of the non-thermoplastic chemical fiber with respect to the fiber raw material in the intermediate | middle layer 2, 50 mass% is preferable and 20 mass% is more preferable. Moreover, as a minimum of the compounding quantity of this non-thermoplastic chemical fiber, 1 mass% is preferable and 5 mass% is especially preferable. In this way, by setting the blending amount of the non-thermoplastic chemical fiber to the fiber material in the intermediate layer 2 within the above range, the gap between the fibers can be reliably and efficiently formed in the sheet-like molded body using the molding sheet 1. As a result, it is possible to improve the rigidity, heat insulation, sound absorption, and lightness of the sheet-like molded body in a well-balanced manner, and to improve the formability by press working. When the amount of the non-thermoplastic chemical fiber exceeds the above upper limit, the contact property between the foaming agent described later, in particular, the foamable microcapsule and the fiber material is lowered, and the density is increased to form a sheet-like molded body. Sufficient bulk may not be imparted, and the elongation rate may decrease or the cushioning property may decrease. Further, when the blending amount of the non-thermoplastic chemical fiber is less than the above lower limit, inhibition of hydrogen bonding becomes insufficient, and the elongation rate of the sheet-like molded product tends to decrease.

  The upper limit of the average fiber length of the non-thermoplastic chemical fiber is preferably 15 mm, and particularly preferably 10 mm. Moreover, as a minimum of the average fiber length of this non-thermoplastic chemical fiber, 1 mm is preferable and 2 mm is more preferable. In this way, by setting the average fiber length of the non-thermoplastic chemical fibers in the above range, it is possible to improve the fiber spacing of the natural fibers while preventing the sheet-like molded body 1 from being broken under the heating of the sheet-like molded body. As a result, the light weight can be realized more reliably. If the average fiber length of the non-thermoplastic chemical fibers exceeds the above upper limit, it becomes difficult to form a uniform sheet in the paper making operation of the molding sheet 1, and a sheet-like molded body using the molding sheet 1 is used. Natural fibers tend to peel off. Further, when the average fiber length of the non-thermoplastic chemical fiber is less than the above lower limit, when the molding sheet 1 is foamed and molded, the entanglement between the fibers is reduced, and the tear and strength of the sheet-like molded body may be reduced. There is sex.

<Foaming agent>
The foaming agent is contained in the intermediate layer 2 together with the natural fibers, thermoplastic synthetic fibers, and non-thermoplastic chemical fibers, and expands the fiber spacing of the fiber material by heating and places closed cells in the sheet. It is. By including this foaming agent in the intermediate layer 2, the fiber spacing of natural fibers and the like is expanded, the heat insulation and sound absorbing properties of the sheet-like molded body using the molding sheet 1 are improved, and further sufficient weight reduction is achieved. Can be achieved.

  The foaming start temperature of the foaming agent is preferably not higher than the melting point of the thermoplastic synthetic fiber. Thus, the foaming start temperature of the foaming agent is not higher than the melting point of the thermoplastic synthetic fiber, so that the thermoplastic synthetic fiber is prevented from melting prior to the foaming start of the foaming agent, and foamed by the melted thermoplastic synthetic fiber. Inhibition of foaming of the agent can be effectively prevented. As a result, lightness, heat insulation, and sound absorption can be reliably imparted to the sheet-like molded body using the molding sheet 1.

  The type of the foaming agent is not particularly limited, and examples thereof include sodium bicarbonate, ammonium carbonate, azodicarbonamide, benzenesulfonyl hydrazide, and foamable microcapsules. Among them, it is preferable to use foamable microcapsules for the reasons described later.

  The foamable microcapsule is obtained by enclosing a liquid having an appropriate boiling point in a microcapsule formed from a thermoplastic polymer. This foamable microcapsule maintains a stable state without expanding in the paper making process of the molding sheet 1, but the liquid encapsulated in the foamable microcapsule is vaporized under the heating of the molded body. As a result, the vapor pressure rises, and the foamable microcapsules formed from the thermoplastic polymer expand. In this way, expandable microcapsules expand under heating during processing of the molded body to expand the fiber spacing of natural fibers, etc., improving the cushioning properties in addition to the lightweight, heat-insulating and sound-absorbing properties of the sheet-like molded body. Can be made.

  The kind of the thermoplastic polymer constituting the foamable microcapsule is not particularly limited, and examples thereof include a vinylidene chloride copolymer, an acrylonitrile copolymer, and an acrylic copolymer. Among these, from the viewpoint of the thermal stability of the thermoplastic polymer, it is preferable to use an acrylic copolymer mainly composed of a nitrile monomer and a (meth) acrylic acid ester monomer.

  The kind of liquid or the like to be enclosed in the expandable microcapsule is not particularly limited, but it is preferable to use a liquid having a boiling point equal to or lower than the softening temperature of the thermoplastic polymer constituting the expandable microcapsule. Cyclopropane, butane, cyclobutane, isobutane, pentane, neopentane, cyclopentane, isopentane, hexane, cyclohexane, 2-methylpentane, 2,2-dimethylbutane, heptane, cycloheptane, octane, cyclooctane, methylheptanes, trimethylpentane And hydrofluoroethers. In addition, these liquids etc. can be used individually by 1 type or in combination of 2 or more types.

  The foaming start temperature of the foamable microcapsule is preferably not higher than the melting point of the thermoplastic synthetic fiber. Specifically, the foaming start temperature of the expandable microcapsule is preferably 80 ° C. or higher and 120 ° C. or lower. For example, when the foaming start temperature of the foamable microcapsule is 90 ° C. and the melting point of the thermoplastic synthetic fiber is 135 ° C., first, (A) the drying temperature of the dryer part in the paper making process of the molding sheet 1 is less than 90 ° C. By setting to, the foamable microcapsule does not expand and the thermoplastic synthetic fiber does not melt in the paper making process. Next, (B) in the step of foaming and pressing the molding sheet 1 to form a molded body, when the heating temperature is gradually increased from, for example, 80 ° C., the thermoplastic synthetic fiber is preceded at about 90 ° C. The expandable microcapsules begin to expand and then the thermoplastic synthetic fiber begins to melt at about 135 ° C. As a result, it is possible to prevent the thermoplastic synthetic fiber from melting prior to the start of expansion of the expandable microcapsule, and to effectively prevent the expansion of the expandable microcapsule due to the melted thermoplastic synthetic fiber. Light weight, heat insulation, and the like can be reliably imparted to the sheet-like molded body using the sheet 1.

  As an upper limit of the compounding quantity of the foamable microcapsule with respect to the fiber material in the intermediate layer 2, 40% by mass is preferable, and 35% by mass is more preferable. Moreover, as a minimum of content of this expandable microcapsule, 15 mass% is preferable and 20 mass% is more preferable. Thus, by making the blending amount of the foamable microcapsules with respect to the fiber material in the intermediate layer 2 into the above range, the foaming in the sheet-like molded body using the molding sheet 1 can be made more uniform, As a result, the lightness and sound absorption of the sheet-like molded body can be improved. In addition, if the blending amount of the foamable microcapsule exceeds the above upper limit, the entanglement between the fiber materials of the sheet-like molded body is reduced, the strength is lowered, and the foamable microcapsule may drop off at the time of molding. In addition, the elongation rate tends to decrease. Moreover, when the blending amount of the foamable microcapsule is less than the above lower limit, the density of the sheet-like molded body is improved, the volume is likely to be lowered, and the sound absorption may be lowered.

<Other optional components>
In addition to the natural fibers, thermoplastic synthetic fibers, non-thermoplastic chemical fibers, and foaming agents, optional components can be appropriately used for the intermediate layer 2 as long as the effects of the present invention are not impaired. Examples of such optional components include light calcium carbonate, heavy calcium carbonate, magnesium carbonate, barium carbonate, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, zinc hydroxide, clay, calcined kaolin, deramikaolin, titanium dioxide, oxidation Fillers such as zinc, silicon oxide, amorphous silica, urea-holimarin resin, polystyrene resin, phenol resin, fine hollow particles; alkyl ketene dimer sizing agent, neutral rosin sizing agent, alkenyl succinic anhydride sizing agent, etc. Sizing agent; polyacrylamide polymer, polyvinyl alcohol polymer, cationized starch, urea / formalin resin, melamine / formalin resin and other paper strength enhancer; acrylamide / aminomethylacrylamide copolymer salt, cationized starch , Polyethylene , Polyethylene oxide (hereinafter sometimes referred to as “PEO”), acrylamide / sodium acrylate copolymer, cationic fixing agent (Haktron KC-100, etc.), etc .; An inhibitor; a sulfuric acid band; a wet paper strength material; a paper thickness improver; a bulking agent; a cationizing agent; a colorant; and a dye can be added by appropriately adjusting the type and content thereof.

(Surface and back layers)
The surface layer 3 and the back layer 4 are structures laminated so as to sandwich the intermediate layer 2 from both sides, and contain natural fibers and thermoplastic synthetic fibers as fiber materials.

<Natural fiber>
Natural fiber is a material constituting the surface layer 3 and the back layer 4. In this way, by including natural fibers in each of the surface layer 3 and the back layer 4, as in the case of the intermediate layer 2 described above, the light weight of the sheet-like molded body using the molding sheet 1 and molding by press working And sufficient response to environmental problems.

  The kind of natural fiber contained in each layer of the surface layer 3 and the back layer 4 is not particularly limited, and is the same as in the case of the intermediate layer 2 described above. Among them, bamboo having high rigidity, kenaf having high fiber strength, It is preferable to use Manila hemp. Moreover, it is more preferable to use the below-mentioned softwood bleached kraft pulp (NBKP) that is easy to obtain and process, has a relatively large paper strength, and can impart good strength to the molding sheet 1.

<Thermoplastic synthetic fiber>
The thermoplastic synthetic fiber is a thermoplastic fiber body contained in the surface layer 3 and the back layer 4. Thus, by including thermoplastic synthetic fibers in each of the surface layer 3 and the back layer 4, as in the case of the intermediate layer 2 described above, high rigidity with respect to the sheet-like molded body using the molding sheet 1, In addition to imparting dimensional stability and sound absorption, it imparts good stretchability to the outer surfaces of both surfaces of the molding sheet 1, and as a result, the moldability by pressing can be further improved.

  It does not specifically limit as a kind of thermoplastic synthetic fiber contained in each layer of the surface layer 3 and the back layer 4, It is the same as that of the case of the above-mentioned intermediate | middle layer 2, Especially in adhesiveness by heat melting with a natural fiber. As a result, the rigidity, dimensional stability, sound absorption, and moldability by press working of the sheet-like molded body using the molding sheet 1 are improved, so that it is preferable to use polyolefin fibers.

  As an upper limit of the average fiber length of the thermoplastic synthetic fiber in each layer of the surface layer 3 and the back layer 4, 5 mm is preferable and 4 mm is more preferable. Moreover, as a minimum of the average fiber length of this thermoplastic synthetic fiber, 0.1 mm is preferable and 2 mm is more preferable. Thus, by making the average fiber length of a thermoplastic synthetic fiber into the said range, the melting efficiency of the thermoplastic synthetic fiber by heating improves, and between the fibers of the natural fiber in the sheet-like molded object using the sheet | seat 1 for shaping | molding. The permeability is further improved. As a result, the sheet-like molded body using the molding sheet 1 can exhibit a high elongation rate during heat processing. In addition, when the average fiber length of this thermoplastic synthetic fiber exceeds the said upper limit, the space | gap between fiber raw materials will reduce and sound absorption property may fall. Moreover, when the average fiber length of the thermoplastic synthetic fiber is less than the above lower limit, the above-described good elongation rate may not be realized.

  In particular, the thermoplastic synthetic fiber of each layer of the surface layer 3 and the back layer 4 has a core-sheath structure, and the melting point of the sheath part of the core-sheath structure is preferably lower than the melting point of the core part. Specifically, the melting point of the sheath part of this core-sheath structure is preferably lower by 100 ° C. or more than the melting point of the core part. The thermoplastic synthetic fiber having the core-sheath structure as described above specifically includes a sheath portion made of a low-melting-point thermoplastic polymer that softens or melts under the heating of the molded body processing of the molding sheet 1, and a molded body. It is a core-sheath type composite fiber composed of a core portion made of a thermoplastic polymer having a high melting point that does not soften or melt under processing heat. That is, since the melting point of the sheath part of the core-sheath structure of the thermoplastic synthetic fiber is lower than the melting point of the core part, the molding sheet 1 has a low melting point sheath part under heating of the molded body processing of the molding sheet 1. It is softened or melted, and the fiber materials are firmly bonded to each other, so that high stretchability and strength that can withstand press working can be exhibited. Furthermore, this molding sheet 1 can exhibit higher strength and waist by maintaining the strength of the sheet with a high melting point core portion that is difficult to soften or melt under heating of the molded body. That is, since each layer of the surface layer 3 and the back layer 4 containing the thermoplastic synthetic fiber having such a core-sheath structure is configured to sandwich the intermediate layer 2, the molding sheet 1 as a whole is particularly excellent in press. Formability by processing can be exhibited.

  The type of core / sheath structure of the thermoplastic synthetic fiber is not particularly limited. For example, PET core / low melting point PET sheath, PP core / high density PE sheath, PP core / low melting point copolymer PE sheath, PP core / CO. -PP sheath etc. are mentioned. Among them, it is preferable to use a PET core / low-melting point PET sheath that imparts high stretchability, strength, waist, and the like to the molding sheet 1 and is particularly excellent in press processing of the molded body.

  In the core-sheath structure of the thermoplastic synthetic fiber, the upper limit of the mass ratio of the sheath part to the core part is preferably 70/30, more preferably 60/40. Moreover, as a minimum of mass ratio with respect to the core part of this sheath part, 30/70 is preferable and 40/60 is more preferable. Thus, by setting the mass ratio of the sheath portion to the core portion within the above range, the molding sheet 1 exhibits high stretchability, strength, waist, and the like, and sufficiently realizes the ease and certainty of processing of the molded body. can do. If the mass ratio of the sheath portion to the core portion exceeds the above upper limit, the bonding between the fiber materials of the molding sheet 1 becomes insufficient, and the strength of the sheet-like molded body using the molding sheet 1 may be reduced. There is sex. Further, if the mass ratio of the sheath portion to the core portion is less than the lower limit, it is difficult to maintain the bonding strength between the fiber materials of the molding sheet 1, and the ease of processing the molded body may be reduced. is there.

  The upper limit of the mass ratio between the natural fibers and the thermoplastic synthetic fibers in each of the surface layer 3 and the back layer 4 is preferably 80/20, and more preferably 75/25. Moreover, as a minimum of mass ratio of this natural fiber and a thermoplastic synthetic fiber, 10/90 is preferable and 40/60 or less is more preferable. Thus, the lightness, rigidity, and dimensions of the sheet-like molded body using the molding sheet 1 by setting the mass ratio of the natural fiber and the thermoplastic synthetic fiber in each layer of the surface layer 3 and the back layer 4 within the above range. In addition to effectively realizing stability and sound absorption, it is possible to more reliably realize improvement in press workability particularly by improving stretchability. Further, the falling off of the foaming agent from the intermediate layer 2 can be effectively prevented or reduced. In addition, when this mass ratio exceeds the said upper limit, in the sheet-like molded object using the sheet | seat 1 for shaping | molding, the tangle of fiber materials will become inadequate, and there exists a tendency for generation | occurrence | production of a tear to increase. Further, if the mass ratio is less than the lower limit, in addition to the possibility that the foaming agent is inhibited from foaming and the density is improved as in the case of the intermediate layer 2 described above, the elongation rate may be excessively increased. The sheet-like molded body using the molding sheet 1 may be easily damaged.

<Foaming agent>
Each layer of the surface layer 3 and the back layer 4 may further contain a foaming agent in addition to the above-mentioned natural fibers and thermoplastic synthetic fibers. The blending amount of the foamable microcapsule with respect to the fiber material in each of the surface layer 3 and the back layer 4 is less than 5% by mass, preferably 3% by mass, and most preferably no compounding. Thus, when the blending amount of the foamable microcapsule with respect to the fiber material in each of the surface layer 3 and the back layer 4 is less than 5% by mass, the foaming agent is a fiber material fiber even under heating of the molded body processing described later. The spacing is not substantially expanded. As a result, the molding sheet 1 can exhibit excellent stretchability, and can realize the ease and certainty of the compact pressing. In addition, when the blending amount of the foamable microcapsule with respect to the fiber material in each layer of the surface layer 3 and the back layer 4 is 5% by mass or more, the foaming agent expands the fiber spacing of the fiber material under heating of the molded body processing described later. As a result, the foaming agent may fall off or the stretchability may decrease.

<Other optional components>
Each layer of the surface layer 3 and the back layer 4 can contain the non-thermoplastic chemical fiber as in the case of the intermediate layer 2. The kind, blending amount, and average fiber length of such non-thermoplastic chemical fibers are the same as in the case of the intermediate layer 2. In addition, each layer of the surface layer 3 and the back layer 4 can contain optional components other than the foaming agent as in the case of the intermediate layer 2.

(Forming sheet)
Thus, as an upper limit of the basic weight of the molding sheet 1 formed from the intermediate layer 2, the surface layer 3, and the back layer 4, 700 g / m ² is preferable, and 600 g / m ² is more preferable. The lower limit of the basis weight of the basis weight of the molded sheet 1 is preferably 100 g / ^{m 2,} and more preferably 150 g / ^{m 2.} Thus, the balance of the lightweight property and rigidity provided to the sheet-like molded object using the molding sheet 1 can be improved by making the basic weight of the molding sheet 1 into the above range. If the basis weight of the molding sheet 1 exceeds the above upper limit, the processability of the molding sheet 1 such as stretching and bending may be reduced. In addition, when the basis weight of the molding sheet 1 is less than the lower limit, the molding sheet 1 tends to be easily broken.

  The upper limit of the thickness of the molding sheet 1 is preferably 1.5 mm, and more preferably 1 mm. Moreover, as a minimum of the thickness of the sheet | seat 1 for shaping | molding, 0.3 mm is preferable and 0.35 mm is more preferable. Thus, by setting the thickness of the molding sheet 1 within the above range, it is possible to make the thickness of the molding sheet 1 uniform and to facilitate winding by the paper machine in the paper making process. If the thickness of the forming sheet 1 exceeds the above upper limit, there is a possibility that the sheet 1 will break during winding by a paper machine in the paper making process. In addition, if the thickness of the molding sheet 1 is less than the above lower limit, there is no bulk at the time of molding, so the sheet-like molded body using the molding sheet 1 cannot exhibit sufficient heat insulation and sound absorption. there is a possibility.

  The upper limit of the disaggregation freeness of the fiber material of the molding sheet 1 is preferably 800 cc, and more preferably 700 cc. Moreover, as a minimum of the disaggregation freeness of the fiber raw material of the sheet | seat 1 for shaping | molding, 580cc is preferable and 600cc is more preferable. Thus, by setting the disaggregation freeness of the fiber material of the molding sheet 1 within the above range, it is possible to effectively prevent or reduce the falling off of the foaming agent from the intermediate layer of the molding sheet 1, and improve the moldability by pressing. Can be made. In addition, when this disaggregation freeness exceeds the said upper limit, processability, such as extending | stretching and a bending, of the shaping | molding sheet 1 may fall. Further, if the disaggregation freeness is less than the above lower limit, the fiber length of the fiber material of the sheet-like molded body using the molding sheet 1 is shortened, and there is a possibility that a decrease in burst strength, square cracks, etc. occur. There is a possibility that the surface area where hydrogen bonds are generated in the natural fiber of the intermediate layer 2 is expanded and foaming is hindered. The disaggregation freeness is a value obtained by measuring the freeness with a Canadian standard freeness tester according to JIS-P8121, after the sample was disaggregated with a standard disaggregator according to JIS-P8220. .

  The upper limit of at least one of the longitudinal direction and the lateral direction in the molding sheet 1 is preferably 20%, and more preferably 15%. Moreover, as a minimum of the elongation rate of at least one of the vertical direction or the horizontal direction in the sheet | seat 1 for shaping | molding, 7% is preferable and 10% is more preferable. As described above, by setting at least one of the longitudinal and lateral elongation rates in the molding sheet 1 within the above range, the molding sheet 1 can be satisfactorily stretched while maintaining sufficient strength to withstand press working. Thus, the formability of the molding sheet 1 by press working is improved. Furthermore, the moldability by the press work of the molding sheet 1 is further improved when the elongation percentages in the longitudinal direction and the lateral direction of the molding sheet 1 are both 10% or more. In addition, when this elongation rate exceeds the said upper limit, the ease of manufacture of the sheet | seat 1 for shaping | molding and low cost property may not be implement | achieved. Moreover, there exists a possibility that the extending | stretching property of the shaping | molding sheet | seat 1 mentioned above may fall that this elongation rate is less than the said minimum. The elongation in at least one of the machine direction and the machine direction is a value calculated in accordance with JIS-P8113 (paper and paperboard-tensile property test method).

The upper limit of the density of the structures in the state where the molding sheet 1 was subjected to only the heat treatment is preferably ^{0.1g / cm 3, 0.05g / cm} 3 is more preferable. Moreover, as a minimum of the density of this structure, 0.02 g / cm < ³ > is preferable and 0.03 g / cm < ³ > is more preferable. Thus, by setting the density of the structure in a state where only the heat treatment is applied to the molding sheet 1 within the above range, the molding sheet 1 exhibits good expansibility and ensures an airway between the fiber materials. However, the ease of pressing the forming sheet 1 can be improved. In addition, when the density of this structure exceeds the said upper limit, processing, such as extending | stretching and bending of the shaping | molding sheet 1, may become difficult. Moreover, when the density of the structure is less than the lower limit, the molding sheet 1 tends to be easily broken during press working.

(Method for producing molding sheet)
As a manufacturing method of the forming sheet 1, a general multilayer paper making method can be used. Specifically, for each layer of the intermediate layer, surface layer and back layer, using raw material slurry containing fiber material for each layer, paper is made through wire part, press part, dryer part, calendar part, reel part, etc. It can be manufactured by winding up. Further, in such a dryer part, drying is performed at a temperature at which the thermoplastic synthetic fiber contained in the molding sheet 1 does not melt and foaming of the foaming agent in the intermediate layer 2 does not start. For example, when the foaming agent in the intermediate layer 2 is a foamable microcapsule, if the melting point of the thermoplastic synthetic fiber is 135 ° C. and the foaming start temperature of the foamable microcapsule is 90 ° C., the drying temperature in the dryer part is Set to less than 90 ° C.

  Examples of the method for applying the foamable microcapsules to paper include an internally added papermaking method in which foamable microcapsules are mixed with a raw slurry to make paper, and spraying foamable microcapsules onto wet paper in the middle of the papermaking process. For example, a method of impregnating an impregnating liquid composed of foamable microcapsules and rubber latex and / or a synthetic resin emulsion by a wet impregnation method can be used.

  The calendar processing method in the calendar part is not particularly limited, and a machine calendar, a super calendar, a gloss calendar, a brush calendar, a mat calendar, a soft calendar, etc. that are set on-machine can be used.

  Also, starch, polyvinyl alcohol, a surface sizing agent, a fluorescent brightening agent are formed on the outer surface of each of the sheet surface layer 3 and the back layer 4 by using a coating method such as size brace or gate roll on the forming sheet 1. Etc. can also be applied.

(Sheet-like molded product)
A sheet-like molded body 11 in FIG. 2 is formed by foaming and press-molding the molding sheet 1 under heating, and includes an intermediate layer 12, a surface layer 13, and a back layer 14. The intermediate layer 12 has a larger thickness and a lower density than the intermediate layer 2 before molding. On the other hand, in each layer of the surface layer 13 and the back layer 14, the width of change in thickness and density is small as compared with the layers of the surface layer 3 and the back layer 4 before the molding process. As described above, the sheet-like molded body 11 can be added while exhibiting good light weight, sound absorption, and heat insulating properties, particularly when the thickness and density of the intermediate layer 12 are greatly changed as compared with those before molding. It can also exhibit rigidity and dimensional stability.

  The sound absorption coefficient of the sheet-like molded body 11 is preferably 0.3 or more, and more preferably 0.4 or more. Thus, by setting the sound absorption coefficient of the sheet-like molded body 11 within the above range, the sheet-like molded body 11 can exhibit good sound absorption properties. For example, in the actual sensation of a healthy person, a good sound absorbing effect can be obtained. I can feel it. The sound absorption coefficient is a value based on JIS-A1409 (measurement method of sound absorption coefficient of the reverberation room method), and is calculated from the decay time of the reverberation quality when sound is suddenly stopped after being emitted in the reverberation room. It is.

If the sheet-shaped molded body 11 is an automobile interior material, the upper limit of the density of the automobile interior material, preferably ^{0.45g / cm 3, 0.1g / cm} 3 is more preferable. Moreover, as a minimum of the density of this interior material for motor vehicles, 0.01 g / cm < ³ > is preferable and 0.02 g / cm < ³ > is more preferable. Thus, by setting the density of the sheet-like molded body 11 which is an automobile interior material within the above range, the rigidity and heat resistance are improved while securing the light weight as the automobile interior material, and further good sound absorption The ability to show off. In addition, by setting the density of the sheet-like molded body 11 that is an automobile interior material within the above range, it is possible to impart good smoothness to the outer surface of the automobile interior material, and as a result, adhere to the outer surface. When the agent is applied, excessive absorption of the adhesive can be effectively prevented. If the density of the automobile interior material exceeds the above upper limit, the sound absorption rate tends to decrease. Further, if the density of the automobile interior material is less than the lower limit, there is a possibility that the rigidity may be lowered and the smoothness of the outer surface may be lowered.

(Manufacturing method of sheet-like molded product)
As above-mentioned, the sheet-like molded object 11 is obtained by making the sheet | seat 1 for shaping | molding under heating and press-molding. As a molding apparatus used for such press molding, a press molding die composed of a male mold and a female mold can be used.

  Regarding the heating and press molding methods, only the molding sheet 1 is heated in advance and pressed with an unheated press molding die, or both the molding sheet 1 and the press molding die are heated. The method to keep is mentioned. Further, the heating method of the molding sheet 1 and the press molding die is not particularly limited. For example, an infrared heating method, an electric heater heating method, a hot air heating method, a steam heating method, a heating oil circulation method, etc. Two or more types can be used in combination. In addition, the heating for expanding the expandable microcapsules may be performed by expanding the foamed microcapsule to a desired size by one heating.

The pressure of the press molding can be adjusted according to the content and content of the fiber material and foaming agent constituting the molding sheet 1, the size, thickness, usage, and the like of the target sheet-like molded body 11. it can. The press molding pressure is preferably 5 kg / cm ² or more and 500 kg / cm ² or less, more preferably 10 kg / cm ² or more and 350 kg / cm ² or less, in order to prevent damage to the sheet-shaped molded body 11, and 30 kg / cm ^2. cm ² or more 250 kg / cm ² or less is particularly preferred. Further, the press molding time can also be adjusted according to the blending amount of the fiber material and foaming agent constituting the molding sheet 1, the size, thickness, usage, etc. of the target sheet-like molded body 11. In the case where molding is performed at the above-described pressing pressure, it is preferable to adjust the pressing time to 2 seconds or more and 20 seconds or less.

  In addition, the sheet | seat for shaping | molding of this invention and a sheet-like molded object using the same are not limited to the said embodiment. For example, different properties can be exhibited by changing and adjusting the blending amounts of natural fibers, thermoplastic synthetic fibers, and non-thermoplastic chemical fibers contained in the molding sheet of the present invention. For example, in the intermediate layer of the molding sheet of the present invention, (A) the blending amount of the natural fiber with respect to the fiber material is 40% by mass or more and 80% by mass or less, and the blending amount of the thermoplastic synthetic fiber is 10% by mass or more and 30% by mass or less. In addition, by making the blending amount of the non-thermoplastic chemical fiber 5% by mass or more and 50% by mass or less, the sheet-like molded body using such a molding sheet exhibits particularly good lightness and soundproofing, It can be suitably used as an automobile interior material. Further, in the intermediate layer of the molding sheet of the present invention, the blending amount of the natural fiber with respect to the fiber material (B) is 10% by mass or more and 50% by mass or less, and the blending amount of the thermoplastic synthetic fiber is 10% by mass or more and 40% by mass or less. Since the amount of the non-thermoplastic chemical fiber is 30% by mass or more and 50% by mass or less, the sheet-like molded body using such a molding sheet exhibits particularly good rigidity and strength. It can be suitably used as a door trim.

  In addition, the molding sheet of the present invention can be a multi-layered sheet material having three or more layers. For example, in the molding sheet of the present invention, the surface layer can have a single-layer structure, the back layer can have a single-layer structure, and the intermediate layer can have a three-layer structure. In the molding sheet of the present invention, the surface layer may have a structure of two or more layers, the back layer may have a structure of two or more layers, and the intermediate layer may have a single-layer structure.

  EXAMPLES Hereinafter, although this invention is explained in full detail based on an Example, this invention is not interpreted limitedly based on description of this Example.

[Examples 1 to 21]
(Manufacture of molding sheet)
As a fiber material constituting the intermediate layer of the molding sheet, natural fiber softwood bleached kraft pulp (NBKP), a single polyolefin fiber having no core-sheath structure as a thermoplastic fiber (“SWP-E400 of Mitsui Chemicals, Inc.) ”, Average fiber length 0.9 mm, melting point 135 ° C.”, and vinylon (Kuraray “VPB303”, average fiber length 3 mm), which is a non-thermoplastic chemical fiber, were adjusted according to the blending amounts shown in Table 1. In addition, as the fiber material constituting each layer of the surface layer and the back layer, softwood bleached kraft pulp (NBKP) which is a natural fiber, polyethylene terephthalate (PET) fiber which is a thermoplastic synthetic fiber having a core-sheath structure as a thermoplastic fiber (Unitika) “4080”, an average fiber length of 3 mm, a melting point of the sheath part of 110 ° C., and a melting point of the core part of 255 ° C. were prepared according to the mass ratio shown in Table 1 as in the case of the intermediate layer.

  In the intermediate layer of the molding sheet, based on the fiber material of the intermediate layer, microcapsules (“Matsumoto Microsphere-F78K” from Matsumoto Yushi Seiyaku Co., Ltd.), which is a foaming agent, are added in the amounts shown in Table 1 and are used A slurry was obtained. The microcapsule has a foaming start temperature of 90 ° C. and a maximum expansion temperature of 170 ° C. In addition, the foaming agent was not mix | blended with each layer of the surface layer and back layer of the said sheet | seat for shaping | molding.

  The raw material slurry includes, as optional components, a foaming agent yield improver (“Hakutron KC-100” by Hakuto Co., Ltd.), a paper dust fall-off preventing agent (“DS4356” by Seiko PMC), a sulfuric acid band, a wet paper strength agent and PEO was added separately.

Subsequently, the raw material slurry was paper-made through a wire part, a press part, a dryer part, and a calendar part to obtain a molding sheet. The drying temperature in this dryer part was adjusted to 80 ° C. Paper was made using a gap former for the wire part, a straight-through type without an open draw for the press part, and a single deck dryer for the dryer part. In the calendar part, a flattening process was performed using a multi-nip calendar. The elongation percentage of the molding sheet was measured based on the following measurement method. The basis weight of the obtained molding sheet was 300 g / m ² .

(Manufacture of sheet-like molded products)
The molding sheet obtained by the manufacturing process described above was molded using a hot press apparatus having male and female molds. The pressing time was 60 seconds, and the pressing temperature was 130 ° C. The density of the molding sheet is shown in Table 1.

[Example 22]
Except that the foaming agent in the intermediate layer was “Matsumoto Microsphere-FN180” manufactured by Matsumoto Yushi Seiyaku Co., Ltd. (foaming start temperature 140 ° C., maximum expansion temperature 195 ° C.), it was the same as Examples 1-21.

[Example 23]
Except for the natural material of the intermediate layer being bamboo, the same as Examples 1-21.

[Example 24]
The same as Examples 1-21, except that the natural material of the intermediate layer was Manila hemp.

[Example 25]
Except that the thermoplastic synthetic fiber of the intermediate layer was a polyethylene terephthalate (PET) fiber (“4080” from Unitika), which is a thermoplastic synthetic fiber having a core-sheath structure, the same as in Examples 1-21.

[Example 26]
The same as Examples 1-21, except that the non-thermoplastic chemical fibers of the intermediate layer were acrylic fibers (Toyobo's “Bipal”, average fiber length of 1 to 2 mm).

[Example 27]
It is the same as that of Examples 1-21, except that the natural material of each layer of the surface layer and the back layer was changed to bamboo.

[Example 28]
It is the same as that of Examples 1-21, except that the natural material of each layer of the surface layer and the back layer was manila hemp.

[Example 29]
The thermoplastic synthetic fiber of each layer of the surface layer and the back layer is a single polyolefin fiber having no core-sheath structure ("SWP-E400" manufactured by Mitsui Chemicals, average fiber length: 0.9 mm, melting point: 135 ° C) Is the same as in Examples 1-21.

[Example 30]
Except for blending microcapsules (“Matsumoto Microsphere-F78K”, Matsumoto Yushi Seiyaku Co., Ltd., foaming start temperature 90 ° C., maximum expansion temperature 170 ° C.), which is a foaming agent, in the ratios shown in Table 1 in the surface layer and the back layer. Is the same as in Examples 1-21.

[Comparative Example 1]
The same as in Examples 1 to 21 except that the intermediate layer does not contain a natural material.

[Comparative Example 2]
The same as in Examples 1 to 21 except that the intermediate layer does not contain thermoplastic synthetic fibers.

[Comparative Example 3]
The same as in Examples 1 to 21, except that the intermediate layer does not contain non-thermoplastic chemical fibers.

[Comparative Example 4]
It is the same as that of Examples 1-21, except not including a foaming agent in an intermediate | middle layer.

[Comparative Example 5]
Except not including a natural material in each surface layer and back layer, it is the same as that of Examples 1-21.

[Comparative Example 6]
It is the same as that of Examples 1-21, except not containing a thermoplastic synthetic fiber in each layer of a surface layer and a back layer.

[Comparative Example 7]
Except for blending microcapsules (“Matsumoto Microsphere-F78K”, Matsumoto Yushi Seiyaku Co., Ltd., foaming start temperature 90 ° C., maximum expansion temperature 170 ° C.), which is a foaming agent, in the ratios shown in Table 1 in the surface layer and the back layer. Is the same as in Examples 1-21.

  About the sheet | seat for shaping | molding obtained by the manufacturing process mentioned above, the elongation rate was measured as follows, and the density, sound absorption rate, and heat insulation property were measured and evaluated as follows about a sheet-like formation body.

(Measurement of elongation)
The elongation rate X (%) of the examples and comparative examples is based on JIS-P8113 (paper and paperboard-tensile property test method), and is pulled until the test piece of the sheet 1 for molding is broken at 150 ° C. When the length immediately before the test piece breaks is X1, and the length of the test piece before the tensile test is X0, the value is calculated by the following formula (1).
X = [(X1-X0) / X0] * 100 (1)
The value in the horizontal direction was measured based on the formula (1). The results are shown in Table 1.

(Density measurement)
The density of an Example and a comparative example was measured based on JIS-P8118 (the test method of thickness and density). The results are shown in Table 1.

(Measurement of sound absorption rate)
The sound absorption coefficient of the examples and comparative examples used random incident sound absorption coefficient as an evaluation index. The random incident sound absorption coefficient is referred to as a reverberation room sound absorption coefficient, and is calculated from the decay time of the reverberation room when sound is suddenly stopped in accordance with JIS-A1409. Specifically, in the center of the floor of a reverberation chamber having a volume of 70 m ³ and a surface area of 95 m ² , the sheet-like molded bodies of Examples and Comparative Examples are installed, and an acrylic plate having a thickness of 17 mm is formed around the ceiling. A diffusion frame plate having a height of 700 mm was installed. The sound source was arranged at a position away from the ceiling interior material. In this way, air vibration by sound is incident on the ceiling surface from a random direction. The results are shown in Table 1.

(Measurement of thermal insulation)
The heat insulating property (W / mk) in Examples and Comparative Examples is thermal conductivity, and was measured using a thermal conductivity measuring device HC-110 manufactured by Eihiro Seiki Co., Ltd. based on the heat flow meter method of JIS-A1412. Value. The measurement was performed under the condition of a temperature of 20 ° C. The results are shown in Table 1. In addition, if heat insulation is 0.052 W / mk or less, since it is excellent in especially heat insulation, it is preferable.

(Evaluation)
As shown in Table 1, Examples 1 to 30 showed a tendency to exhibit good elongation, sound absorption and heat insulation as compared with Comparative Examples 1 to 7.

  As mentioned above, the sheet | seat for shaping | molding of this invention and a sheet-like molded object using the same can be used for a ceiling interior material, a building material, etc. of a motor vehicle.

DESCRIPTION OF SYMBOLS 1 Sheet | seat for shaping | molding 2 Intermediate | middle layer 3 Surface layer 4 Back layer 11 Sheet-like molded object 12 Intermediate | middle layer 13 Surface layer 14 Back layer

Claims (6)

A sheet for molding comprising a surface layer, an intermediate layer and a back layer, containing a fiber material and a foaming agent,
The intermediate layer contains natural fibers, thermoplastic synthetic fibers and non-thermoplastic chemical fibers as fiber materials,
The surface layer and the back layer contain natural fibers and thermoplastic synthetic fibers as fiber materials,
The molding sheet, wherein the content of the foaming agent relative to the fiber material in each of the surface layer and the back layer is less than 5% by mass.   In the intermediate layer, the blending amount of the natural fiber with respect to the fiber material is 10 mass% or more and 80 mass% or less, the blending amount of the thermoplastic synthetic fiber is 10 mass% or more and 40 mass% or less, and the blending amount of the non-thermoplastic chemical fiber is 1. The molding sheet according to claim 1, wherein the molding sheet is not less than 50% by mass and not more than 50% by mass.   The molding sheet according to claim 1 or 2, wherein in each of the surface layer and the back layer, a mass ratio of natural fibers to thermoplastic synthetic fibers is 10/90 or more and 80/20 or less. The thermoplastic synthetic fibers of the surface layer and the back layer have a core-sheath structure,
The molding sheet according to claim 1, wherein the melting point of the sheath part of the core-sheath structure is lower than the melting point of the core part.   The molding sheet according to any one of claims 1 to 4, wherein in the intermediate layer, the foaming start temperature of the foaming agent is not higher than the melting point of the thermoplastic synthetic fiber.   The sheet-like molded object shape | molded by foaming and press-working the sheet | seat for shaping | molding of any one of Claims 1-5.

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