JP2005226178A - Interior substrate for automobile and interior material for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an interior substrate which is used for an automobile and has a light weight, excellent heat resistance and excellent rigidity, and to provide an interior material for an automobile. <P>SOLUTION: This interior substrate 10 for an automobile, comprising a fiber layer 12 and a thermoplastic resin sheet layer 14 laminated to at least one main surface of the fiber layer 12, is characterized in that the layer 12 comprises a non-woven fabric prepared by arranging a fiber web comprising two or more kinds of staple fibers in the thickness direction of the fiber layer 12, and the staple fibers constituting the non-woven fabric comprise polyester-based adhesive staple fibers having a polymer prepared by melt-mixing a modified polybutylene terephthalate (polyester A) having a melting temperature of 180 to 220°C with a polyester B having a melting temperature of ≤180°C in a mass mixing ratio A/B of 10/90 to 80/20. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an automobile interior material that can be used as a ceiling material, a rear tray material, a door material and the like of an automobile, and an automobile interior base material that is the basis of these automobile interior materials.

As an automobile interior base material, it is preferable that it is lightweight and excellent in rigidity, heat resistance and the like. For the purpose of improving such physical properties, for example, Patent Document 1 proposes an automobile interior base material made of a nonwoven fabric laminate. Patent Document 2 proposes a fiber and a cushion material for the purpose of improving heat resistance.
JP 2000-229369 A Japanese Patent Laid-Open No. 2003-247121

However, the interior base material disclosed in Patent Document 1 is still heavy and not sufficiently lightened as described in the examples with a basis weight of 940 g / m ² . Further, even when the cushion material using the fiber disclosed in Patent Document 2 is used as an automobile interior base material, it is an experiment that a basis weight of 1000 g / m ² or more is required to ensure heat resistance and rigidity. Therefore, it is not possible to reduce the weight sufficiently.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an automobile interior base material and an automobile interior material that are lightweight and excellent in heat resistance and rigidity.

  The automobile interior base material according to the present invention includes a fiber layer and a thermoplastic resin sheet layer laminated on at least one main surface of the fiber layer. The fiber layer is made of a nonwoven fabric in which a fiber web containing two or more kinds of short fibers is oriented in the thickness direction of the fiber layer, and the modified polybutylene terephthalate having a melting temperature of 180 to 220 ° C. as the short fibers constituting the nonwoven fabric. A polyester-based adhesive short fiber having a polymer in which (polyester A) and polyester B having a melting temperature of 180 ° C. or less are melt-mixed within a mass mixing ratio of A / B = 10/90 to 80/20 Contains.

  When the automobile interior base material is bent, one of the pair of main surfaces of the base material is extended and the other main surface is contracted. In this automobile interior base material, elongation is suppressed by the thermoplastic resin sheet, and the fiber web is oriented in the thickness direction, so that it can counter the pressure from the side that shrinks. Excellent rigidity. And since rigidity is excellent, the amount of fibers, ie, a fabric weight, can be made low, and weight reduction is achieved. In addition, since the polyester-based adhesive short fibers are excellent in heat resistance, the automobile interior base material is excellent in heat resistance.

  In the automobile interior base material according to the present invention, the polyester-based adhesive short fibers have a core-sheath type composite fiber structure having a core component and a sheath component, and the sheath component has a melting temperature of 180 to 220 ° C. The modified polybutylene terephthalate (polyester A) and polyester B having a melting temperature of 180 ° C. or less are made of a polymer obtained by melt mixing within a mass mixing ratio of A / B = 10/90 to 80/20. This may be a feature. If it does in this way, since a sheath component plays the role of adhesion | attachment with other fibers and a core component becomes a part of frame | skeleton, since the number of bonding points in a nonwoven fabric can be maintained, rigidity can be improved.

  In the automobile interior base material according to the present invention, the thermoplastic resin sheet layer is composed of a long-fiber nonwoven fabric containing two or more types of long fibers, and at least one type of long fibers is configured as the long fibers constituting the long-fiber nonwoven fabric. It contains low-melting-length long fibers containing a thermoplastic resin whose melting point is 30 ° C. or more lower than the resin and whose softening point is 90 ° C. or more, and the low-melting-length long fibers are in a state of being bonded at the contact portion between the fibers May be a feature. If it does in this way, at the time of normal temperature and the temperature rise, a long-fiber nonwoven fabric becomes difficult to extend, and it is excellent in rigidity and heat resistance. Moreover, at the time of shaping | molding, a moldability can be improved by melting a low melting-point continuous fiber.

  In the automobile interior base material according to the present invention, the thermoplastic resin sheet layer may be made of a film mainly composed of polybutylene terephthalate. Polybutylene terephthalate is excellent in moldability, has a high crystallization rate, and suppresses dimensional changes at high temperatures after crystallization.

  The automobile interior base material according to the present invention includes an adhesive layer for adhering these layers between the fiber layer and the thermoplastic resin sheet layer, and the adhesive layer is made of a hot-melt film or a low-melting resin nonwoven fabric. This may be a feature. In this way, the fiber layer and the thermoplastic resin sheet layer can be firmly bonded, so that the rigidity is improved.

  The interior material for automobiles according to the present invention includes the above-described interior substrate for automobiles. This automotive interior material is lightweight and has excellent heat resistance and rigidity.

  The automobile interior material according to the present invention may include a skin material layer. If it does in this way, design nature will improve.

  The automobile interior material according to the present invention may include a non-breathable film layer. In this way, since the ventilation can be suppressed, the antifouling property is improved.

  ADVANTAGE OF THE INVENTION According to this invention, the interior material for motor vehicles and the interior material for motor vehicles which were lightweight and excellent in heat resistance and rigidity are provided.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a diagram schematically showing a configuration of an automobile interior material according to the present embodiment. FIG. 2 is a diagram schematically showing the configuration of the automobile interior base material provided in the automobile interior material of FIG. 1.

  As shown in FIG. 1, an automotive interior material (hereinafter also simply referred to as “interior material”) 1 according to this embodiment includes an automotive interior base material (hereinafter also simply referred to as “interior material”) 10, A skin material layer 20, an adhesive layer 30, and a non-breathable film layer 40 are provided. As shown in FIG. 2, the interior base material 10 includes a fiber layer 12, a thermoplastic resin sheet layer 14, and an adhesive layer 16.

  The fiber layer 12 is made of a nonwoven fabric in which a fiber web containing two or more types of short fibers is oriented in the thickness direction of the fiber layer 12. The fiber web constituting the nonwoven fabric contains polyester-based adhesive short fibers.

  The polyester-based adhesive short fiber is composed of a modified polybutylene terephthalate (hereinafter referred to as polyester A) having a melting temperature of 180 to 220 ° C. and a polyester B having a melting temperature of 180 ° C. or less in a mass mixing ratio A / B = 10. It is composed of a polymer obtained by melt mixing at / 90 to 80/20.

  Here, the melting temperature refers to a temperature corresponding to an endothermic peak that can be confirmed in a melting curve measured by a differential scanning calorimeter (hereinafter referred to as DSC). In the melting curve measured by DSC, the endothermic peak that cannot be confirmed refers to the temperature measured with a melting point microscope.

  The main component of polyester A having a melting temperature of 180 to 220 ° C. must be a modified polybutylene terephthalate composed of repeating units of butylene terephthalate. In general, the melting temperature of unmodified polybutylene terephthalate (PBT) is 230 to 235 ° C., and the melting temperature must be lowered to use it as polyester A in this embodiment. The melting temperature of PBT can be lowered by copolymerization. The copolymer component is preferably a bifunctional carboxylic acid component such as isophthalic acid (IPA), phthalic acid, adipic acid, or sebacic acid, or a bifunctional glycol component such as ethylene glycol, diethylene glycol, propylene glycol, or polyethylene glycol. . Considering the production cost and the heat resistance of the polyester, it is more preferable to copolymerize IPA. Two or more kinds of copolymer components may be used.

  Polyester B having a melting temperature of 180 ° C. or lower is preferably obtained by copolymerizing polyethylene terephthalate (PET), PBT, or polypropylene terephthalate (PPT) with at least one compound. As the copolymer component, IPA, phthalic acid, adipic acid, sebacic acid, ethylene glycol, diethylene glycol, propylene glycol, butanediol, polyethylene glycol, polybutylene glycol and the like are preferable. In particular, IPA copolymerized PET in which the main constituent component is a repeating unit of ethylene terephthalate is more preferable because of the cost of the raw materials and the ease of the production method. Two or more copolymerization components may be used.

  Here, it is considered that polyester B is acting as a component for adhering the short fibers constituting the fiber web, and polyester A is acting as a component for suppressing remelting of the adhesion point in the 90 to 100 ° C. region. Therefore, when the melting temperature of the polyester A is lower than 180 ° C., the function of suppressing remelting is lowered, and remelting of the bonding point of the heat-bonded short fibers cannot be prevented.

  Moreover, in order not to reduce productivity and adhesiveness, the melting temperature of polyester A must be 220 ° C. or lower. Therefore, it is important that the melting temperature of the polyester A is in the range of 180 to 220 ° C, preferably 185 to 215 ° C. In order to obtain the copolymerized PBT in the melting temperature range by copolymerization of IPA, it is possible to make the IPA copolymerization rate 5 to 25 mol%, more preferably 10 to 20 mol%.

  On the other hand, when the melting temperature of polyester B exceeds 180 ° C., it is not preferable because adhesion of short fibers is suppressed and adhesiveness is lowered. Therefore, it is important that the melting temperature of the polyester B is 180 ° C. or lower, and preferably 160 ° C. or lower.

  In particular, when using IPA copolymerized PET due to the cost of raw materials and the ease of production method, it is possible to make the melting temperature 180 ° C. or less by setting the IPA copolymerization rate to 25 to 50 mol%. More preferably, it is 30-40 mol%.

  In addition, polyester A and polyester B may contain additives such as matting agents such as titanium dioxide and lubricants.

  The mass mixing ratio of polyester A and polyester B is 10/90 to 80/20. If the ratio of the polyester A component is less than 10%, the ratio of the polyester A component that suppresses remelting of the adhesion point is too low, and remelting of the adhesion point of the heat-bonded short fibers cannot be prevented. On the other hand, if it exceeds 80%, the ratio of the polyester B component having adhesive performance at low temperature is excessively decreased, and the adhesiveness at the time of thermal bonding is decreased, which is not preferable. The mass mixing ratio of polyester A and polyester B is more preferably 20/80 to 60/40. In addition, the mass mixing ratio here is a mass mixing ratio of the polyester A and the polyester B, and a polyester of another component may be further mixed.

  It is known that when two kinds of polyesters are melt-mixed, a transesterification reaction occurs between the polyesters, and then a random copolymer is obtained via a block copolymer. However, in the present embodiment, the effect is exhibited by not randomly copolymerizing both polyesters in the mixed polyester.

  The polyester-based adhesive short fiber is preferably one in which at least a part of a melt-mixed polyester of polyester A and polyester B (hereinafter referred to as a thermal adhesive component) is exposed around the fiber cross section, and is a concentric or eccentric core sheath. Type, side-by-side type, sea-island type, etc. If the concentric core-sheath type is used, the yarn-forming property is good, and if the eccentric type is used, the latent crimp is obtained. Therefore, it is preferable to select an appropriate composite form according to the application.

  In the case of a core-sheath form, it is preferable to use the above thermal adhesive component as a sheath component and a polyester having a melting temperature of 220 ° C. or higher as the core component. If it does in this way, since a sheath component plays the role of adhesion | attachment with other fibers and a core component becomes a part of frame | skeleton, since the number of bonding points in a nonwoven fabric can be maintained, rigidity can be improved. As the polyester of the core component, polyethylene terephthalate, polypropylene terephthalate, and polybutylene terephthalate can be preferably used. In addition, recycled polyester can be used from the viewpoint of resource reuse and environmental protection. Further, the core component may be formed of two or more kinds of mixed polyesters, and the core component may be in a bimetal composite form. Additives such as matting agents such as titanium dioxide and lubricants may be added to the core component. The core / sheath composite ratio is preferably 20/80 to 80/20, more preferably 40/60 to 60/40 on a mass basis.

  The fineness of the polyester-based adhesive short fibers is preferably 1.5 dtex or more so that the single fiber is excellent in rigidity and the entire fiber layer 12 is excellent in rigidity. Moreover, it is preferable that it is 6.6 dtex or less so that the number of adhesion points does not decrease due to the decrease in the number of short polyester-based adhesive fibers and the rigidity of the entire fiber layer 12 does not decrease.

  The fiber length of the polyester-based adhesive short fibers is preferably 30 to 70 mm so that the productivity of the fiber web is excellent. The cross-sectional shape of the polyester-based adhesive short fibers is not particularly limited, and may be circular or non-circular.

  As short fibers other than the polyester-based adhesive short fibers constituting the fiber web, synthetic fibers such as polyethylene terephthalate fibers and natural fibers such as hemp, kenaf, and sisal can be used.

  In addition, polyethylene terephthalate / polyethylene terephthalate composite fibers and polyethylene terephthalate / polybutylene terephthalate composite fibers having different intrinsic viscosities can be used. If the arrangement of the components in these composite fibers is side-by-side type or eccentric type, the shrinkage of one component due to heat causes the winding to occur, increasing the bulk of the fiber web or nonwoven fabric, and entanglement between the fibers. The degree of fusion increases and the press pressure at the time of molding increases, so that the fusion strength is increased.

  The fineness of the short fibers other than the polyester-based adhesive short fibers is preferably 6.6 dtex or more so that the rigidity of the single fiber is excellent and the rigidity of the entire fiber layer 12 is excellent. Moreover, it is preferable that it is 16.5 dtex or less so that the number of adhesion points does not decrease due to the decrease in the number of fibers and the rigidity of the entire fiber layer 12 does not decrease. Preferably it is 11 to 14.3 dtex.

  The fiber length of the short fibers other than the polyester-based adhesive short fibers is preferably 30 to 70 mm so that the productivity of the fiber web is excellent. The cross-sectional shape of the short fibers other than the polyester-based adhesive short fibers is not particularly limited, and may be circular or non-circular (for example, T, Y, X, etc.). Or a hollow fiber may be sufficient.

  The content ratio of the polyester-based adhesive short fibers and other short fibers is preferably (polyester-based adhesive short fibers) :( other fibers) = 50: 50 to 80:20. When the polyester-based adhesive short fibers are less than 50% by mass, the number of adhesion points between fibers in the fiber layer 12 decreases, and the rigidity and heat resistance may be reduced. On the other hand, when the amount of the polyester-based adhesive short fibers exceeds 80% by mass, the amount of other short fibers forming the skeleton of the fiber layer 12 decreases, and the rigidity and heat resistance may be reduced.

  The above-described fiber web can be formed as a unidirectional fiber web by a conventional dry method (for example, a card method). Further, it can be formed as a cross web in which fibers are crossed in the fiber web production direction by a cross layer or the like. Furthermore, it can also be formed as a laminated fiber web in which a unidirectional fiber web and a cross web are laminated.

  The above-described fiber web is oriented in the thickness direction of the fiber layer 12. In order to orient the fiber web in the thickness direction of the fiber layer 12, for example, as shown in FIG. 3, the fiber web 18 is described in a pleating machine, a strut machine (registered trademark, European Patent Application No. 0350627). The nonwoven fabric manufacturing apparatus) or air-laying machine (for example, V21 / R-K12, V21 / K12 manufactured by Ferrer) may be folded in a zigzag shape and then compressed. The fiber web 18 oriented in this way is heated to a temperature equal to or higher than the melting point of the melt-mixed polymer of polyester-based adhesive short fibers, and the polyester-based adhesive short fibers are fused and fixed to form a nonwoven fabric.

The basis weight of the nonwoven fabric is preferably 300 g / m ² or more so as to be excellent in rigidity and heat resistance, and preferably 600 g / m ² or less so as to be lightweight. More preferably, it is 300-500 g / m < ² >. Further, the thickness of the nonwoven fabric is preferably 5 mm or more so as to be excellent in rigidity and heat resistance, and is preferably 10 mm or less so as to be lightweight.

  As a thermoplastic resin sheet which comprises the thermoplastic resin sheet layer 14, a long fiber nonwoven fabric (for example, spun bond nonwoven fabric), a mesh, a film (especially polybutylene terephthalate film), etc. can be used. These thermoplastic resin sheets are not easily stretched at room temperature and at elevated temperature, and are excellent in rigidity and heat resistance.

  The long fiber nonwoven fabric includes two or more types of long fibers, and the long fibers include a thermoplastic resin having a melting point lower by 30 ° C. or more and a softening point of 90 ° C. or higher than the resin constituting at least one type of long fibers. Contains low melting long fibers. This low melting point long fiber is in a state of being bonded at the contact portion between the fibers.

  The reason why the melting point of the low melting point long fiber is 30 ° C. or more lower than the melting point of at least one other kind of long fiber is to eliminate the influence on fibers other than the low melting point long fiber when molding, This is to ensure stability. The reason why the softening point of the low melting point long fiber is 90 ° C. or more is to maintain the rigidity of the interior base material 10 even when the temperature of the vehicle interior is increased.

  As a combination of low-melting long fibers and other long fibers (shown as “low-melting long fibers / other long fibers”), low-melting point polyethylene terephthalate / polyethylene terephthalate, polyethylene / polypropylene, polypropylene / polybutylene terephthalate, polybutylene terephthalate / Examples thereof include polyethylene terephthalate and nylon / polyethylene terephthalate. The low melting point long fiber itself may be a composite fiber of low melting point polyethylene terephthalate and polyethylene terephthalate or polybutylene terephthalate.

  The mass ratio of the low melting point long fibers and other long fibers is preferably (low melting point long fibers) :( other long fibers) = 5: 95 to 50:50. When the fiber amount of the low-melting long fibers is less than 5% by mass, the number of adhesion points between the fibers decreases, the rigidity of the long-fiber nonwoven fabric itself decreases, and as a result, the rigidity and heat resistance of the interior base material 10 decrease. And preferably 20% by mass or more. Moreover, even if the amount of the low melting point long fiber exceeds 50% by mass, when the low melting point long fiber is melted at the time of molding, the amount of other long fibers that maintain the shape of the long fiber non-woven fabric decreases, and the long fiber non-woven fabric itself This is because the rigidity and heat resistance of the interior base material 10 are reduced as a result.

  If the thermoplastic resin sheet layer 14 is made of polybutylene terephthalate, the polybutylene terephthalate is preferable because it is excellent in moldability, has a high crystallization rate, and suppresses dimensional changes at high temperatures after crystallization.

  In the interior base material 10 according to the present embodiment, as shown in FIG. 2, the thermoplastic resin sheet layer 14 described above is laminated on both the upper and lower surfaces (main surfaces) of the fiber layer 12 described above. The thermoplastic resin sheet layer 14 may be laminated on at least one of the upper and lower surfaces of the fiber layer 12.

  Between the fiber layer 12 and the thermoplastic resin sheet layer 14, an adhesive layer 16 for adhering both layers is provided. If the adhesive layer 16 is provided in this manner, the fiber layer 12 and the thermoplastic resin sheet layer 14 can be firmly bonded, and the rigidity is improved. The adhesive layer 16 can be composed of a hot melt film or a low melting point resin nonwoven fabric.

  The hot melt film is preferably a hot melt film that can be fused at about 90 to 120 ° C. Examples of the resin composition include polyester-based, polyamide-based, and olefin-based resins. A thickness of about 30 to 50 μm can be used.

The low melting point resin nonwoven fabric is preferably a nonwoven fabric made of a low melting point resin that can be fused at about 90 to 120 ° C. Examples of the resin composition include polyester-based, polyamide-based, and olefin-based resins. A fabric weight of about ²⁰ to 50 g / m ² can be used. Such a low melting point resin nonwoven fabric is obtained, for example, by discharging a molten resin obtained by melting the above-described resin from a nozzle and collecting the discharged molten resin with a collector (for example, a conveyor, a roll, etc.). be able to.

  The interior base material 10 according to the present embodiment can be manufactured as follows. That is, the fiber layer 12 is heated at a temperature higher than the melting point of the melt-mixed polymer of polyester-based adhesive short fibers (for example, the melting point + 20 ° C.). Next, the thermoplastic resin sheet layer 14 and the adhesive layer 16 are integrated using a heat roll or the like. Next, the integrated product of the thermoplastic resin sheet layer 14 and the adhesive layer 16 is heated at a temperature higher than the melting point of the adhesive layer 16 (for example, a melting point + 20 ° C.). Then, the thermoplastic resin sheet layer 14 / adhesive layer 16 / fiber layer 12 / adhesive layer 16 / thermoplastic resin sheet layer 14 are laminated in this order.

  Returning to FIG. 1, as the skin material constituting the skin material layer 20 of the interior material according to the present embodiment, for example, a fiber sheet such as a nonwoven fabric, a knitted fabric, or a woven fabric can be used. In particular, a nonwoven fabric excellent in moldability is suitable, and among these, a needle punch nonwoven fabric is preferred. By providing the skin material in this way, the design properties are improved. The skin material can be integrated with the interior base material 10 by previously integrating the adhesive layer 30 made of a hot melt film or the like using a heat roll or the like and utilizing the fusing property of the hot melt film.

  Examples of the non-breathable film constituting the non-breathable film layer 40 include, for example, an olefin resin (adhesive layer) and a nylon resin (breath-proof layer), or an olefin resin (adhesive layer) and a polypropylene resin (breath-proof layer). ) Can be used. Thus, by providing the non-breathable film layer 40, ventilation can be suppressed and antifouling property improves. Such a two-layer film can be obtained by, for example, co-extrusion with a T-die or by extruding only an air-blocking layer from the T-die and then extruding only an adhesive layer from the T-die and directly laminating the air-proof layer. it can.

  When the interior material 1 includes the skin material layer 20 as in the interior material 1 according to the present embodiment, the non-breathable film layer 40 is on the side opposite to the skin material layer 20 with respect to the interior substrate 10. It is preferable to arrange them. The non-breathable film layer 40 and the interior base material 10 can be integrated using the adhesiveness of the adhesive layer of such a two-layer film.

  As in the case of the interior base material 10, the interior material 1 according to the present embodiment is manufactured by heating each constituent member and then molding by cooling using a die matched to the interior material 1. Can do.

  Next, operations and effects of the above-described automobile interior base material 10 and the automobile interior material 1 will be described.

  When the automobile interior base material 10 bends, one of the upper and lower surfaces of the interior base material 10 extends and the other shrinks. At this time, as shown in FIG. 4, between the thermoplastic resin sheets, when the fiber web is oriented in the direction perpendicular to the thickness direction, the fiber web is displaced by the force received from the thermoplastic resin sheet side of the lower surface, Easy to bend and low rigidity.

  On the other hand, in the interior base material 10 according to the present embodiment, as shown in FIG. 5, the thermoplastic resin sheet 14 suppresses elongation and shrinks due to the fiber web being oriented in the thickness direction. It can counter the pressure from the surface side, and therefore has excellent rigidity. And since rigidity is excellent, the amount of fibers, ie, a fabric weight, can be made low, and weight reduction is achieved. Moreover, since the polyester-based adhesive short fibers are excellent in heat resistance, the automobile interior base material 10 is excellent in heat resistance.

  And since the automotive interior material 1 according to this embodiment includes the above-described automotive interior base material 10, it is lightweight and has excellent heat resistance and rigidity.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  For example, when the thermoplastic resin sheet layer 14 in FIG. 2 is a non-breathable sheet layer such as a film, the non-breathable film layer 40 of the automobile interior material 1 is also used as the thermoplastic resin sheet layer 14. In this case, the non-breathable film layer 40 may not be added to the interior base material 10 again.

Hereinafter, although the Example of a vehicle interior base material is demonstrated with a comparative example, this invention is not limited to this.
(Example 1)
(1) Preparation of fiber layer Modified polybutylene terephthalate having a hollow composite fiber having a fineness of 14.3 dtex (polyethylene terephthalate / polyethylene terephthalate composite fiber having different intrinsic viscosities, fiber length: 51 mm) and a melting temperature of 210 ° C. A polyester in which (Polyester A) and a polyester B having a melting temperature of 120 ° C. are melt-mixed within a mass mixing ratio A / B = 50/50 as a sheath component and polyethylene terephthalate as a core component After blending 70% by mass of the core-sheath type adhesive short fiber (fineness: 4.4 dtex, fiber length: 51 mm), the unidirectional fiber web obtained by opening by the card method is crossed by a cross layer, A cross lay web (weight per unit: 30 g / m ² , thickness: 5 mm) was formed.

This fiber web was folded in a zigzag pattern with a height of 5 mm by a pleating machine, and the fiber web was oriented in the thickness direction of the fiber layer. Then, in a state where the fiber web is compressed by applying pressure from the folding direction, the fiber web is supplied to a heating furnace set at a temperature of 210 ° C., and only the sheath component of the polyester-based core-sheath-type adhesive short fiber is fused and melted. A fiber layer (weight per unit area: 400 g / m ² , thickness: 5 mm) made of a non-woven fabric was formed.
(2) Production of interior base material Spunbond nonwoven fabric (weight per unit: 70 g) comprising 80% by mass of long fibers made of polyethylene terephthalate and 20% by mass of low-melting polyethylene terephthalate long fibers (melting point: 195 ° C., softening point: 150 ° C.) / M ² ) was prepared.

Moreover, a low melting point resin nonwoven fabric (weight per unit area: 25 g / m ² , thickness: 0.2 mm) made of low melting point polyester (melting point: 120 ° C.) was prepared.

  The spunbond nonwoven fabric and the low melting point resin nonwoven fabric were integrated with a hot roll, and then heated in a far-red furnace set at a temperature of 200 ° C. On the other hand, the above-mentioned fiber layer was heated again in a hot air circulating furnace set at a temperature of 230 ° C.

Each member taken out from each furnace is laminated in the order of spunbond nonwoven fabric / low melting point resin nonwoven fabric / fiber layer / low melting point resin nonwoven fabric / spunbond nonwoven fabric, and cooled using a flat plate press. These were pressed and pressed to produce an automobile interior base material having a basis weight of 590 g / m ² and a thickness of 5 mm.
(Example 2)
A fiber layer was produced in exactly the same manner as in Example 1. Further, a low melting point resin nonwoven fabric exactly the same as in Example 1 was prepared. Furthermore, a polybutylene terephthalate film (weight per unit: 30 g / m ² , thickness: 20 μm) was prepared.

  The polybutylene terephthalate film and the low melting point resin non-woven fabric were integrated with a hot roll, and then heated in a far-red furnace set at a temperature of 130 ° C. On the other hand, the fiber layer was heated again in a hot air circulating furnace set at a temperature of 230 ° C.

Each member taken out from each furnace was laminated in the order of polybutylene terephthalate film / low melting point resin nonwoven fabric / fiber layer / low melting point resin nonwoven fabric / polybutylene terephthalate film, and a flat plate press was used. These were cold-pressed and pressure-bonded to produce an automobile interior base material having a basis weight of 510 g / m ² and a thickness of 5 mm.
(Comparative Example 1)
When forming the fiber layer, instead of the polyester core-sheath adhesive short fiber of Example 1, a sheath component (melting point: 110 ° C., softening point: low melting point polyethylene terephthalate copolymerized with 40 mol% of isophthalic acid component) 70 ° C.), and polyester core-sheath adhesive short fibers (fineness: 4.4 dtex, fiber length: 51 mm, cross-sectional shape: circular), which uses polyethylene terephthalate as a core component, and Example 1 in the same manner, the fiber layer (basis weight: 400 g / ^{m 2,} thickness: 5 mm), and automobile interior base material (basis weight: 590 g / ^{m 2,} thickness: 5 mm) was prepared.
(Comparative Example 2)
A cross lay web manufactured in exactly the same manner as in Example 1 (basis weight: 30 g / m ² , thickness: 5 mm) was simply laminated (fiber orientation was perpendicular to the thickness direction of the fiber layer), It is supplied to a heating furnace set at a temperature of 210 ° C. and only the sheath component of the polyester-based core-sheath-type adhesive short fiber is fused, and a fiber layer composed of a fused nonwoven fabric (weight per unit: 400 g / m ² , thickness: 5 mm) Formed.

Next, an automobile interior base material (basis weight: 590 g / m ² , thickness: 5 mm) was produced in exactly the same manner as in Example 1.
(Comparative Example 3)
A fiber layer (weight per unit: 600 g / m ² , thickness: 5 mm) was produced in exactly the same manner as in Example 1. Subsequently, this fiber layer was heated again in a hot air circulating furnace set at a temperature of 230 ° C. Then, the fiber layer was taken out from the furnace, cold-pressed using a flat plate press, and pressed to produce an automobile interior base material having a basis weight of 600 g / m ² and a thickness of 5 mm.
<Evaluation of heat resistance>
A strip-shaped test piece having a length of 300 mm in the longitudinal direction (the traveling direction of the pleats in the fiber layer) and 50 mm in the lateral direction of each automobile interior base material was collected. An area from the longitudinal end of the strip-shaped test piece to 70 mm was fixed on a rectangular parallelepiped base, and the remaining 230 mm area was projected from the rectangular parallelepiped base. Next, with this state maintained, the sample was left in a thermostatic bath set at a temperature of 90 ° C. for 4 hours, and the amount of sag (unit: mm) at the tip of the portion protruding from the rectangular parallelepiped base was measured. If this amount of sag is 10 mm or less, it can be evaluated that it is excellent in heat resistance. The evaluation results are shown in Table 1.
<Rigidity evaluation>
A strip-shaped test piece of 150 mm in the vertical direction and 50 mm in the horizontal direction was collected from each automobile interior base material. This strip-shaped test piece was arrange | positioned so that it might straddle on the two support stand arrange | positioned at intervals of 100 mm. Subsequently, the central part (a part 50 mm from the support base) between the support bases was pressed downward at a pressurization speed of 20 mm / min with a press wedge. This pressurization state was sensed by a tensile tester (Orientec, Tensilon UCT-500), and the load (maximum point load) at the point where the load became maximum was measured and recorded. If this maximum point load is 13 N / 50 mm or more, it can be evaluated that it is excellent in rigidity. The evaluation results are shown in Table 1.

  As shown in Table 1, the interior base materials of Examples 1 and 2 are excellent in heat resistance and rigidity while being lightweight.

It is a figure which shows typically the structure of the interior material for motor vehicles concerning embodiment. It is a figure which shows typically the structure of the interior member for motor vehicles with which the interior material for motor vehicles of FIG. 1 is provided. It is a figure for demonstrating the method to orientate the fiber web which comprises a fiber layer to the thickness direction of a fiber layer. It is a figure for demonstrating a mode of bending in the interior substrate for motor vehicles by which the fiber web which comprises a fiber layer is orientated in the direction orthogonal to the thickness direction of a fiber layer. It is a figure for demonstrating the mode of bending in the interior material for motor vehicles by which the fiber web which comprises a fiber layer is orientated to the thickness direction of a fiber layer.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Automotive interior material, 10 ... Automotive interior base material, 12 ... Fiber layer, 14 ... Thermoplastic resin sheet layer, 16 ... Adhesive layer, 18 ... Fiber web, 20 ... Skin material layer, 30 ... Adhesive layer, 40 ... non-breathable film layer.

Claims (8)

An automotive interior base material comprising a fiber layer and a thermoplastic resin sheet layer laminated on at least one main surface of the fiber layer,
The fiber layer is composed of a nonwoven fabric in which a fiber web containing two or more kinds of short fibers is oriented in the thickness direction of the fiber layer, and the modified fiber having a melting temperature of 180 to 220 ° C. is used as the short fibers constituting the nonwoven fabric. Polyester adhesive short having a polymer in which butylene terephthalate (polyester A) and polyester B having a melting temperature of 180 ° C. or less are melt-mixed within a mass mixing ratio of A / B = 10/90 to 80/20. An automobile interior base material characterized by containing a fiber.   The polyester-based adhesive short fibers have a core-sheath type composite fiber structure having a core component and a sheath component, and the sheath component is a modified polybutylene terephthalate (polyester A) having a melting temperature of 180 to 220 ° C. 2) and a polyester B having a melting temperature of 180 ° C. or lower and a polymer obtained by melt mixing within a range of mass mixing ratio A / B = 10/90 to 80/20. The interior material for automobiles as described.   The thermoplastic resin sheet layer is made of a long fiber nonwoven fabric containing two or more types of long fibers, and the long fiber constituting the long fiber nonwoven fabric has a melting point of 30 ° C. or more lower than the resin constituting at least one type of long fiber. And a low melting point long fiber containing a thermoplastic resin having a softening point of 90 ° C. or higher, and the low melting point long fiber is in a state of being bonded at a contact portion between the fibers. 2. An automobile interior base material according to 2.   The automobile interior base material according to claim 1 or 2, wherein the thermoplastic resin sheet layer is made of a film containing polybutylene terephthalate as a main component.   2. An adhesive layer for adhering these layers is provided between the fiber layer and the thermoplastic resin sheet layer, and the adhesive layer is made of a hot melt film or a low melting point resin nonwoven fabric. The automobile interior base material according to any one of -4.   An automotive interior material comprising the automotive interior base material according to any one of claims 1 to 5.   The automobile interior material according to claim 6, further comprising a skin material layer.   The automobile interior material according to claim 6 or 7, further comprising a non-breathable film layer.

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