Automobile ceiling material and method for manufacturing same

Abstract

Provided is an automobile ceiling material having excellent recyclability and handleability. An automobile ceiling material 1 comprises: a core material layer 2 composed of a core material nonwoven fabric; and a skeleton layer 3 composed of a skeleton nonwoven fabric and laminated on each of an upper surface and a lower surface of the core material layer 2. The core material nonwoven fabric is formed of PET fibers and LPET fibers, and the skeleton nonwoven fabric is formed of the PET fibers and the LPET fibers. The automobile ceiling material 1 is formed from the same resin in terms of composition, and therefore has excellent recyclability after use. The content ratio of the LPET fibers in the skeleton nonwoven fabric is equal to or greater than the content ratio of the LPET fibers in the core material nonwoven fabric. Thus, in the automobile ceiling material 1, the skeleton layers sandwiching the upper and lower surfaces of the core material layer have rigidity due to melting and solidifying of the LPET fibers through heat treatment, whereby the ceiling material facilitates shape retention when, e.g., attached to the vehicle body, and has excellent handleability.

Description

Automotive ceiling material and its manufacturing method

[0001] The technology of this specification relates to an automobile ceiling material for interior materials for automobile use.

[0002] Automotive ceiling materials are hung inside the ceiling of the vehicle body. For this reason, automotive ceiling materials are required to be lightweight and strong. Patent Document 1 describes an automotive ceiling material that is lightweight and strong, in which a base material formed from glass fiber and resin fiber and a nonwoven fabric are press-integrated.

[0003] Automobile ceiling materials are required to be recycled under the Automobile Recycling Law. However, the automobile ceiling material described in Patent Document 1 contains glass fiber and resin fiber, which causes a problem of poor recyclability. In response to this, Patent Document 2 describes an automobile ceiling material in which the constituent materials of the base material layer, skin layer, and adhesive layer are all polyester fiber, thereby improving recyclability.

[0004] JP-A No. 8-325914 JP-A No. 11-268596

[0005] However, the automobile ceiling material described in Patent Document 2 has a surface layer and an adhesive layer laminated on one side of a base material layer, which has the problem of insufficient rigidity and the risk of poor handling.

[0006] The problem to be solved by the technology of this specification has been made in view of the above points, and an object of the technology is to provide an automobile ceiling material that is excellent in recyclability and ease of handling.

[0007] An automobile ceiling material according to an embodiment of the present specification is an automobile ceiling material obtained by laminating and heat-treating nonwoven fabrics formed from fibers, and is characterized in that it comprises a core layer made of a core nonwoven fabric, and a skeletal layer made of a skeletal nonwoven fabric laminated on each of the upper and lower surfaces of the core layer, wherein the core nonwoven fabric is formed from PET fibers and LPET fibers, and the skeletal nonwoven fabric is formed from the PET fibers and the LPET fibers, and the content of the LPET fibers in the skeletal nonwoven fabric is equal to or greater than the content of the LPET fibers in the core nonwoven fabric.

[0008] According to the automotive ceiling material according to the embodiment of the present specification, the laminated nonwoven fabric constituting the automotive ceiling material is formed from polyethylene terephthalate (PET) fiber and low melting point PET fiber (LPET fiber), i.e., formed from the same polyethylene terephthalate composition, and therefore has excellent recyclability. Furthermore, in the automotive ceiling material according to the embodiment, the content of LPET fiber in the skeleton nonwoven fabric is equal to or greater than the content of LPET fiber in the core nonwoven fabric. Therefore, the skeleton layers sandwiching both the upper and lower surfaces of the core layer are rigid due to the melting and solidification of the LPET fiber by heat treatment, and the automotive ceiling material can easily maintain its shape when attached to the vehicle body, resulting in excellent handleability.

[0009] In the above-mentioned automobile ceiling material, the content of the LPET fibers in the framework nonwoven fabric may be 60 to 90% by mass.

[0010] This allows the skeletal layer made of the skeletal nonwoven fabric to have rigidity, and allows for excellent handling properties.

[0011] In the above-mentioned automobile ceiling material, the PET fibers contained in the core nonwoven fabric may contain hollow PET fibers.

[0012] This allows the automobile ceiling material to be lighter in weight and easier to handle.

[0013] In addition, the above-mentioned automobile ceiling material may have a film layer laminated on the upper surface side or the lower surface side.

[0014] This can improve the sound insulation of the automobile ceiling material.

[0015] Here, the method for manufacturing the automobile ceiling material may be such that the skeletal nonwoven fabric forming the skeletal layer, the core nonwoven fabric forming the core layer, and the skeletal nonwoven fabric forming the skeletal layer are laminated together and entangled by needle punching.

[0016] This allows the skeletal layer, the core layer, and the skeletal layer to be integrated together.

[0017] In the above-described method for manufacturing an automobile ceiling material, the needle punching may be performed from both the upper surface side and the lower surface side to intertwine the needles.

[0018] This can increase the strength of the automobile ceiling material.

[0019] The automobile ceiling material of the embodiment can be made to have excellent recyclability and handling properties.

[0020] 1 is a cross-sectional view of an image of a ceiling material for an automobile according to a first embodiment; FIG. 2 is a cross-sectional view of an image of a ceiling material for an automobile according to a second embodiment; FIG. 3 is a cross-sectional view of an image of a ceiling material for an automobile according to a third embodiment.

[0021] (First Embodiment) Hereinafter, an automobile ceiling material 1 according to a first embodiment of the present specification will be described. Note that the scope of the present invention is not limited to the scope disclosed in the embodiments. As shown in FIG. 1 , the automobile ceiling material 1 according to the first embodiment is an automobile ceiling material 1 formed by layering and heat-treating nonwoven fabrics formed from fibers, and includes a core layer 2 made of a core nonwoven fabric and a skeletal layer 3 made of a skeletal nonwoven fabric layered on each of the upper and lower surfaces of the core layer 2. The core nonwoven fabric is formed from PET fibers and LPET fibers, and the skeletal nonwoven fabric is formed from PET fibers and LPET fibers, with the LPET fiber content in the skeletal nonwoven fabric being equal to or greater than the LPET fiber content in the core nonwoven fabric. The skeletal nonwoven fabric is entangled by needle punching to form the skeletal layer 3, and the core nonwoven fabric is entangled by needle punching to form the core layer 2. The automobile ceiling material 1 is formed by laminating a skeletal layer 3, a core material layer 2 and another skeletal layer 3 together, and interlacing the skeletal layer 3 from the upper surface side and the lower surface side by needle punching.

[0022] A nonwoven fabric is a sheet in which a sheet-like web in which fibers are accumulated in a certain direction or randomly is mechanically entangled, bonded with heat-sealed fibers, entangled in water, or chemically bonded with an adhesive resin. The nonwoven fabric used in the automotive ceiling material 1 of the embodiment does not require adhesive resin or heat-sealed resin, and does not contain any resin composition other than the fibers that make up the nonwoven fabric, so it can be mechanically entangled by needle punching, which has excellent recyclability.

[0023] The fibers used in the nonwoven fabric may be made of a thermoplastic resin that is easily recyclable. Examples of thermoplastic resin compositions that can be used for easily recyclable fibers include polyethylene, polypropylene, polyester, polyamide, polyurethane, and acrylic. In another embodiment, a polyester with excellent recyclability may be used. In yet another embodiment, PET (polyethylene terephthalate) may be used as the polyester. PET fibers may include polyethylene terephthalate fiber and low melting point PET fiber. PET fiber is a high melting point PET fiber with a melting point of 220 to 260°C. LPET fiber is a low melting point PET fiber with a melting point of 100 to 200°C. Since these resins can be freely copolymerized, any resin containing PET as the main component may be used. Other resin components may also be used as long as they do not impair the performance of the resin.

[0024] Fibers used in nonwoven fabrics include those composed of a single type of resin composition and those composed of multiple types of resins (for example, PET resin and LPET resin). Fibers composed of a single type of resin include round cross-sectional structure fibers (including flat cross-sections, triangular cross-sections, irregular cross-sections, etc.) and hollow cross-sectional structure fibers (including porous hollow cross-sectional structures). By using hollow cross-sectional structure fibers, the automobile ceiling material 1 can be made lightweight and strong, and further, can have excellent heat insulation properties. Fibers composed of multiple types of resins include core-sheath structure fibers and sea-island structure fibers. Note that the LPET fiber in this embodiment can be a core-sheath structure fiber with a PET resin as the core and an LPET resin as the sheath.

[0025] The fiber fineness can be 1 to 30 denier. This is because the automobile ceiling material 1 can be made lightweight and rigid. If the fiber fineness is less than 1 denier, the fibers are thin and the automobile ceiling material 1 may not have sufficient strength, and the required rigidity may not be met. On the other hand, if the fiber fineness exceeds 30 denier, the weight of the automobile ceiling material 1 may increase. In another embodiment, the fiber fineness can be 2 to 25 denier, and in yet another embodiment, it can be 3 to 20 denier. Note that denier is a unit of measurement for fiber thickness, and is the weight in grams of a 9000 m length of fiber.

[0026] The automobile ceiling material 1 of the first embodiment includes a core layer 2 made of a core nonwoven fabric and a skeletal layer 3 made of a skeletal nonwoven fabric laminated on each of the upper and lower surfaces of the core layer 2. The automobile ceiling material 1 of the embodiment has excellent recyclability because the nonwoven fabrics forming all layers (core layer 2 and skeletal layer 3) are made of PET fibers and are formed from the same resin composition. Furthermore, the automobile ceiling material 1 of the embodiment has an LPET fiber content equal to or greater than the LPET fiber content in the core nonwoven fabric. Therefore, the skeletal layers 3 sandwiching both the upper and lower surfaces of the core layer 2 are rigid due to the melting and solidification of the LPET fibers by heat treatment, making it easy to maintain its shape when attached to a vehicle body as a ceiling material and providing excellent handleability.

[0027] A skin layer made of a skin nonwoven fabric can be provided on the lower surface side (inside the vehicle compartment) of the skeleton layer 3 laminated on the lower surface of the core layer 2. The skin layer can be used to decorate the automobile ceiling material 1. The nonwoven fabric that forms the skin layer is made of PET fiber and / or LPET fiber, and since it is made of the same PET fiber as the automobile ceiling material 1 (core layer 2 and skeleton layer 3), the automobile ceiling material 1 provided with the skin layer has excellent recyclability.

[0028] The core nonwoven fabric and skeletal nonwoven fabric that form the automobile ceiling material 1 are each made by carding a mixture of PET fibers and / or LPET fibers into webs (sheets of fiber aggregates), which are then entangled by needle punching. The skeletal nonwoven fabric that forms the skeletal layer 3, the core nonwoven fabric that forms the core layer 2, and the skeletal nonwoven fabric that forms the skeletal layer 3 are layered from top to bottom in this order, and are entangled by needle punching from the top and bottom sides, respectively, to form the automobile ceiling material 1.

[0029] The needle punching process involves the reciprocating motion of needles to hook fiber bundles onto the needles and push them into the web, entangling the fibers and forming a nonwoven fabric. The needle punching process does not require adhesive resins or heat-sealing resins, and does not involve the mixing of resin compositions other than the fibers that form the nonwoven fabric, making it highly recyclable.

[0030] The surface density of the skeletal nonwoven fabric forming the skeletal layer 3 is 100 to 300 g / m 2 This is because the skeletal layer 3 can be made rigid. When the surface density of the skeletal nonwoven fabric forming the skeletal layer 3 is 100 g / m 2 On the other hand, if the surface density is less than 300 g / m, the rigidity may be insufficient and the handling may be poor. 2 In another embodiment, the surface density of the skeletal nonwoven fabric forming the skeletal layer 3 is 150 to 250 g / m 2 It can be said that:

[0031] The number of needles (needle density) by needle punching of the skeletal nonwoven fabric forming the skeletal layer 3 is 200 to 1000 needles / cm 2 This is because the skeletal layer 3 can have both rigidity and flexibility. 2 If the penetration number is less than 1000 / cm, the fiber may have flexibility but insufficient rigidity, resulting in poor handling. 2 If the penetration density exceeds 1000 / cm, the rigidity is ensured but the flexibility is insufficient, and the handling may be poor. 2 In yet another embodiment, 400 to 600 lines / cm 2 It can be said that:

[0032] The surface density of the core nonwoven fabric forming the core layer 2 is 300 to 800 g / m 2 This is because the core layer 2 can have heat insulating properties. When the surface density of the core nonwoven fabric forming the core layer 2 is 300 g / m 2If the surface density is less than 800 g / m, the thickness may be insufficient and the heat insulating properties may be poor. 2 In another embodiment, the surface density of the core nonwoven fabric forming the core layer 2 is 400 to 600 g / m. 2 It can be said that:

[0033] The number of needles (needle density) by needle punching of the core nonwoven fabric forming the core layer 2 is 50 to 100 / cm 2 This is because the core layer 2 can have a certain thickness and can have heat insulating properties. 2 If the penetration number is less than 100 / cm, the strength may be insufficient despite the thickness, and the handling may be poor. 2 If the thickness exceeds 1000 sq. m, the strength is ensured but the thickness is insufficient, and the heat insulating property may be poor. 2 It can be said that:

[0034] The number of needles punched from the upper surface side and the lower surface side to integrate the skeletal layer 3, the core material layer 2 and the skeletal layer 3 (needle density) is 30 to 100 needles / cm 2 This is because the material can be sufficiently intertwined as an automobile ceiling material 1 and can have heat insulating properties. 2 If the penetration number is less than 100 / cm, the skeletal layer 3, the core material layer 2 and the skeletal layer 3 may not be sufficiently intertwined. 2 If the thickness exceeds 100 μm, the automobile ceiling material 1 may become dense and have poor heat insulation. In another embodiment, the number of needle punches from the upper surface side and the lower surface side that integrate the skeleton layer 3, the core material layer 2, and the skeleton layer 3 may be 40 to 80 needles / cm. 2 It can be said that:

[0035] The nonwoven fabric of the automotive ceiling material 1, in which the core nonwoven fabric and the skeletal nonwoven fabric are laminated and needle-punched, can be thermoformed to form the automotive ceiling material 1 as an interior material. Thermoforming is performed by a preliminary bonding process (nonwoven fabric formation process) and a heat molding process (processing process). The preliminary bonding process heats the nonwoven fabric to form a moldable nonwoven fabric, which is an intermediate formed body. The heat molding process integrates the moldable nonwoven fabric formed in the preliminary bonding process into an integrated ceiling material (molded product) using a mold that matches the shape of the automobile ceiling portion. The furnace temperature during these thermoforming processes can be 150 to 220°C. This is because it can smooth the surface of the nonwoven fabric. If the furnace temperature is less than 150°C, the LPET fiber may not be sufficiently melted, which may result in an inability to smooth the surface. On the other hand, if the temperature of the furnace exceeds 220°C, there is a risk that not only the LPET fiber but also the PET fiber will melt, which may result in a deterioration in the heat insulating properties of the automobile ceiling material 1. In another embodiment, the temperature of the furnace can be set to 160 to 210°C, and in yet another embodiment, it can be set to 170 to 200°C.

[0036] The automobile ceiling material 1 that has been subjected to the preliminary joining process and the heat molding process is assembled to the inside of the automobile ceiling on the automobile production line and used as the automobile ceiling material. Since the automobile ceiling material 1 is formed solely from polyethylene terephthalate, it has excellent recyclability after its intended use is fulfilled and the automobile in which it is assembled is dismantled and scrapped.

[0037] Other technical ideas that can be understood from the first embodiment will be described below.

[0038] In the above-mentioned automobile ceiling material, a surface layer made of a surface nonwoven fabric may be provided on the lower surface of the skeleton layer laminated on the lower surface of the core material layer.

[0039] This allows the skin layer to decorate the automobile ceiling material.

[0040] In the above-mentioned method for manufacturing an automobile ceiling material, the skeletal nonwoven fabric forming the skeletal layer, the core nonwoven fabric forming the core layer, the skeletal nonwoven fabric forming the skeletal layer, and the skin nonwoven fabric forming the skin layer can be laminated together and entangled by needle punching.

[0041] This allows the skeletal layer, the core layer, the skeletal layer and the skin layer to be integrated.

[0042] Second Embodiment Next, an automotive ceiling material 1A according to a second embodiment of the present specification will be described. As shown in FIG. 2, the automotive ceiling material 1A according to the second embodiment has a film layer 4 laminated on the upper or lower surface of the automotive ceiling material 1 according to the first embodiment. Furthermore, the automotive ceiling material 1A according to the second embodiment may have a decorative layer 5 made of a knitted or printed skin laminated on the lower surface (inside the vehicle compartment) of the automotive ceiling material 1A, if necessary. The film layer 4 and the decorative layer 5 are adhered to the automotive ceiling material 1A by an adhesive layer 6. Other parts are the same as those of the automotive ceiling material 1 according to the first embodiment, so the same reference numerals as those in the first embodiment are used and their description will be omitted.

[0043] The film layer 4 is a film that inhibits the breathability of the automobile ceiling material 1A. The automobile ceiling material 1A, whose breathability is inhibited by the film layer 4, enhances the sound-blocking effect and can inhibit the inflow of sound from the ceiling associated with sound and vibration outside the vehicle into the passenger compartment. Furthermore, the automobile ceiling material 1A laminated with the film layer 4 blocks the inflow and outflow of air and inhibits the inflow of dirt components contained in the air, thereby inhibiting dirt and discoloration associated with dirt in the automobile ceiling material 1A.

[0044] The film layer 4 is formed from a PET film so as not to impede the recyclability of the automobile ceiling material 1A, and the weight of the film layer 4 is 10 to 80 g / m 2(Film thickness: 7 to 60 μm). This is because the sound insulation effect of the automobile ceiling material 1A can be enhanced, dirt and discoloration due to dirt can be suppressed, and the moldability of the automobile ceiling material 1A can be facilitated. The basis weight of the film layer 4 is 10 g / m 2 If the weight is less than 80 g / m, the PET film may be difficult to form. 2 If the film layer 4 has a weight per unit area of ​​15 to 60 g / m², the film layer 4 may wrinkle during bonding by the adhesive layer 6, which will be described later, and the formability of the automobile ceiling material 1A may become difficult. 2 (film thickness: 10 to 40 μm), and in yet another embodiment, 20 to 40 g / m 2 (film thickness: 15 to 30 μm).

[0045] The decorative layer 5 decorates the interior side of the automobile ceiling material 1A and gives the automobile ceiling material 1A a luxurious feel, and a knitted surface or a printed surface can be used as the decorative layer 5. The knitted surface is a fabric made by knitting fibers, and the printed surface is a nonwoven fabric with a print applied to its surface. The knitted surface and the printed surface are made of PET fiber so as not to impede the recyclability of the automobile ceiling material 1A. The basis weight of the decorative layer 5 is 100 to 500 g / m 2 This is because the automotive ceiling material 1A can be given a luxurious feel. 2 If the weight of the decorative layer 5 is less than 500 g / m, the decorative layer 5 may be visible due to the characteristics of the knitted or printed skin, and the automotive ceiling material 1A may not be able to have a luxurious feel. 2 If the weight of the decorative layer 5 exceeds 150 to 400 g / m, the decorative layer 5 may be excessively decorated and the lightweight property of the automotive ceiling material 1A may be impaired, although the decorative layer 5 may have a luxurious feel. 2 In yet another embodiment, the thickness is 200 to 300 g / m 2 It can be said that:

[0046] The adhesive layer 6 is an adhesive component for laminating the film layer 4 and the decorative layer 5 to the automobile ceiling material 1A by thermocompression bonding. The adhesive layer 6 is formed from LPET (low melting point PET) so as not to impede the recyclability of the automobile ceiling material 1A. An LPET web or an LPET film can be used as the adhesive layer 6. The LPET fiber forming the LPET web can be not only LPET fiber, but also a core-sheath fiber with a PET resin as the core and an LPET resin as the sheath. The basis weight of each of the LPET web and LPET film as the adhesive layer 6 is 10 to 80 g / m 2 This is because the film layer 4 or the decorative layer 5 can be adhered to the automobile ceiling material 1A. 2 If the thickness is less than 80 g / m, the amount of the adhesive layer 6 is too small, and there is a risk that the film layer 4 or the decorative layer 5 cannot be adhered to the automobile ceiling material 1A. 2 In another embodiment, the weight of the adhesive layer 6 is 15 to 60 g / m 2 In yet another embodiment, the thickness may be 20 to 40 g / m 2 It can be said that:

[0047] The adhesive layer 6 can also be used in the form of a multilayer film laminated on one or both sides of the film layer 4. When the film layer 4 is laminated on the upper side of the automobile ceiling material 1, a two-layer film is used in which the LPET adhesive layer 6 is laminated on the underside of the film layer 4. When the film layer 4 is laminated on the lower side of the automobile ceiling material 1, a three-layer film is used in which the LPET adhesive layer 6 is laminated on both the top and bottom sides of the film layer 4. By using a multilayer film in which LPET is laminated on one or both sides of the film layer 4, the film layer 4 and the decorative layer 5 can each be laminated by thermocompression bonding to the automobile ceiling material 1A.

[0048] The automobile ceiling material 1A according to the second embodiment can be formed by thermocompression bonding a film layer 4 to the upper surface or lower surface of the automobile ceiling material 1 of the first embodiment with an adhesive layer 6. Furthermore, the automobile ceiling material 1A according to the second embodiment can be formed by thermocompression bonding a decorative layer 5 to the lower surface (inside of the vehicle compartment) of the automobile ceiling material 1A with an adhesive layer 6, as needed.

[0049] The preliminary bonding process (nonwoven fabric forming process) of the automobile ceiling material 1A of the second embodiment is performed by thermoforming (thermocompression bonding) the film layer 4 to the upper or lower surface of the automobile ceiling material 1 of the first embodiment using the adhesive layer 6, and then, if necessary, thermoforming (thermocompression bonding) the decorative layer 5 to the lower surface using the adhesive layer 6. The preliminary bonding process of the automobile ceiling material 1A can also be performed by overlapping the film layer 4 on the upper side of the automobile ceiling material 1 of the first embodiment via the adhesive layer 6, and the decorative layer 5 on the lower side via the adhesive layer 6, and then thermoforming (thermocompression bonding) these together to form a laminate.

[0050] The pre-bonded automobile ceiling material 1A is subjected to a heat molding process (processing step) using a mold that is matched to the shape of the ceiling portion of the automobile, and processed into a ceiling material (molded product). The temperature of the heating furnace during these heat molding and heat molding processes can be the same temperature (150 to 220°C) as the temperature of the heating furnace in the first embodiment.

[0051] (Third embodiment) Next, a vehicle ceiling material 1B according to a third embodiment of this specification will be described. As shown in Figure 3, the vehicle ceiling material 1B of the third embodiment has a nonwoven fabric layer 7 laminated on the upper surface side of the vehicle ceiling material 1A of the second embodiment. The nonwoven fabric layer 7 is adhered to the upper side of the film layer 4 of the vehicle ceiling material 1B by an adhesive layer 6. Since the other parts are the same as the vehicle ceiling material 1A according to the second embodiment, the same reference numerals as in the second embodiment are used and their description will be omitted.

[0052] The nonwoven fabric layer 7 is provided on the automotive ceiling material 1B to ensure adhesive strength when components (not shown) are placed on the upper side of the automotive ceiling material 1B and adhered to the upper side of the automotive ceiling material 1B with hot melt or adhesive. Spunbond nonwoven fabric, spunlace nonwoven fabric, etc. can be used as the nonwoven fabric layer 7. Spunbond nonwoven fabric and spunlace nonwoven fabric for the nonwoven fabric layer 7 have a porous structure, so when components are attached to the automotive ceiling material 1B with hot melt or adhesive, the resin constituting the hot melt or adhesive can penetrate into the porous pores of the nonwoven fabric layer 7, thereby ensuring adhesive strength for the components. The spunbond nonwoven fabric and spunlace nonwoven fabric for the nonwoven fabric layer 7 are formed from PET fibers so as not to impair the recyclability of the automotive ceiling material 1B. The hot melt can be used in any form, such as powder, stick, or film. Furthermore, the adhesive may be not only an adhesive itself but also a sheet-like adhesive such as double-sided tape.

[0053] The adhesive layer 6 of the third embodiment adheres the nonwoven fabric layer 7 to the upper side of the film layer 4 of the automobile ceiling material 1B, and can be the same as the adhesive layer 6 of the second embodiment (except for the form of a multilayer film laminated on one or both sides of the film layer 4). In addition, parts of the third embodiment include silencers, reinforcing parts, sheet metal, harness cables, etc.

[0054] Other technical ideas that can be understood from the third embodiment will be described below.

[0055] In the above-mentioned automobile ceiling material, a nonwoven fabric layer made of a PET nonwoven fabric may be provided on the upper surface side of the film layer.

[0056] This ensures sufficient adhesive strength when attaching components to the automobile ceiling material using hot melt or adhesive.

[0057] (First Embodiment) The first embodiment will be described in more detail below with reference to examples. In the examples of the first embodiment, test examples were created and compared in which the types and ratios of fibers constituting the core nonwoven fabric forming the core layer 2, the types and ratios of fibers constituting the skeletal nonwoven fabric forming the skeletal layer 3, and the needle punch penetration number of the skeletal nonwoven fabric forming the skeletal layer 3 were changed. The core nonwoven fabric and skeletal nonwoven fabric of the test examples were each formed by carding a fiber mixture into a web, and then entangling each web with needle punching. The skeletal nonwoven fabric forming the skeletal layer 3, the core nonwoven fabric forming the core layer 2, and the skeletal nonwoven fabric forming the skeletal layer 3 were layered from top to bottom in this order, and then entangled with needle punching from the top and bottom sides, respectively, to form a nonwoven fabric that would become the automotive ceiling material 1. The nonwoven fabric that would become the automotive ceiling material 1 was subjected to a preliminary bonding treatment at 190°C for 2 minutes and processed into a molded nonwoven fabric for the automotive ceiling material 1. The processed molding nonwoven fabrics were evaluated by measuring the flexural modulus gradient as described below. All of the examples of the first embodiment were breathable.

[0058] (Bending elasticity gradient) The bending elasticity gradient was measured in accordance with JIS K7203 (JIS K7171 (ISO178)) by placing a test piece (50 mm × 150 mm molding nonwoven fabric) on a three-point bending test jig (support distance 100 mm, wedge R 3.2 mm) with the indoor side facing up, and applying a load to the center at a rate of 50 mm / min. Then, a bending elasticity gradient of 20 N / 50 mm / cm or more was evaluated as ○, and a bending elasticity gradient of less than 20 N / 50 mm / cm was evaluated as ×.

[0059] Details of the fibers (PET fibers, hollow PET fibers, and LPET fibers) forming the core nonwoven fabric, skeleton nonwoven fabric, and skin nonwoven fabric are shown in Table 1.

[0060]

[0061] Details of the test examples of the automotive ceiling material 1 of the first embodiment are shown in Tables 2 to 4, including the types and ratios of fibers constituting the core nonwoven fabric that forms the core layer 2, the types and ratios of fibers constituting the skeletal nonwoven fabric that forms the skeletal layer 3, and evaluations of the needle punch penetration number and bending elasticity gradient. Test examples 1 to 3, 5, 6, 8, 9, and 11 to 14 are working examples, test examples 4, 7, and 10 are comparative examples, and test example 5 is the best working example.

[0062]

[0063]

[0064]

[0065] (Test Examples 1 to 4) Test Examples 1 to 4 are fabrics in which the core material layer 2 contains 30 wt % hollow PET fiber, 70 wt % LPET fiber, and a surface density of 400 g / m 2 Web penetration of 80 strands / cm 2 The core nonwoven fabric was needle-punched to a surface density of 200 g / m. The upper and lower skeletal layers 3 of the core layer 2 were made of PET fiber and LPET fiber at different ratios. 2 The skeletal nonwoven fabric was needle-punched with a specified penetration number from the top and bottom sides to integrate the skeletal layer 3, the core material layer 2, and the skeletal layer 3. The penetration number (needle density) from the top and bottom sides was 60 needles / cm. 2 In Test Examples 1 and 2, a web of 10 wt % PET fiber and 90 wt % LPET fiber (Test Example 1) and a web of 20 wt % PET fiber and 80 wt % LPET fiber (Test Example 2) were used for the skeleton layer 3, respectively, and the penetration was 200 fibers / cm. 2 Test example 3 uses a web of 30 wt % PET fiber and 70 wt % LPET fiber for the skeleton layer 3, and has a penetration of 600 threads / cm. 2 Test example 4 is a test example using a framework nonwoven fabric subjected to needle punching, and the bending elasticity gradient was 20 N / 50 mm / cm or more. Test example 5 is a test example using a framework layer 3 made of a web of 40 wt % PET fiber and 60 wt % LPET fiber, and the penetration number was 600 / cm. 2In Test Example 4, the skeletal nonwoven fabric was needle-punched, and the bending modulus gradient was less than 20 N / 50 mm / cm. In Test Example 4, the content of LPET fiber in the skeletal nonwoven fabric was less than the content of LPET fiber in the core nonwoven fabric, which is presumably why the skeletal layers 3 sandwiching the upper and lower surfaces of the core layer 2 lacked rigidity.

[0066] (Test Examples 5 to 7) Test Examples 5 to 7 were fabricated using a core material layer 2 containing 40 wt% hollow PET fiber, 60 wt% LPET fiber, and a surface density of 400 g / m 2 Web penetration of 80 strands / cm 2 The core nonwoven fabric was needle-punched to a surface density of 200 g / m. The upper and lower skeletal layers 3 of the core layer 2 were made of PET fiber and LPET fiber at different ratios. 2 The skeletal nonwoven fabric was needle-punched with a specified penetration number from the top and bottom sides to integrate the skeletal layer 3, the core material layer 2, and the skeletal layer 3. The penetration number (needle density) from the top and bottom sides was 60 needles / cm. 2 In Test Examples 5 and 6, a web of 30 wt % PET fiber and 70 wt % LPET fiber (Test Example 5) and a web of 40 wt % PET fiber and 60 wt % LPET fiber (Test Example 6) were used for the skeleton layer 3, respectively, and the penetration was 600 fibers / cm. 2 Test example 7 uses a web of 50 wt % PET fiber and 50 wt % LPET fiber for the skeleton layer 3, and the penetration number is 600 / cm. 2 In Test Example 7, the skeletal nonwoven fabric was needle-punched, and the bending modulus gradient was less than 20 N / 50 mm / cm. In Test Example 7, the content of LPET fiber in the skeletal nonwoven fabric was less than the content of LPET fiber in the core nonwoven fabric, which is presumably why the skeletal layers 3 sandwiching the upper and lower surfaces of the core layer 2 lacked rigidity.

[0067] (Test Examples 8 to 10) Test Examples 8 to 10 were fabricated using a core material layer 2 with a surface density of 300 g / m2 and varying the ratio of PET fiber to LPET fiber. 2 Web penetration of 80 strands / cm 2The core nonwoven fabric was needle-punched. The upper and lower skeletal layers 3 of the core layer 2 were made of 40 wt % PET fiber, 60 wt % LPET fiber, and a surface density of 200 g / m 2 Web penetration of 600 threads / cm 2 The number of needles (needle density) punched from the upper surface side and the lower surface side to integrate the skeleton layer 3, the core material layer 2 and the skeleton layer 3 was 60 / cm. 2 In Test Examples 8 to 10, a skin nonwoven fabric forming a skin layer was provided on the lower surface of a skeletal nonwoven fabric forming skeletal layer 3, which was laminated on the lower surface of a core nonwoven fabric forming core layer 2, and needle punching was performed from the upper and lower surfaces to integrate skeletal layer 3, core layer 2, skeletal layer 3, and skin layer. Test Examples 8 and 9 are test examples in which a web containing 50 wt % hollow PET fiber and 50 wt % LPET fiber (Test Example 8) and a web containing 40 wt % hollow PET fiber and 60 wt % LPET fiber (Test Example 9) were used as the core nonwoven fabric forming core layer 2, and each had a bending modulus gradient of 20 N / 50 mm / cm or more. Test Example 10 is a test example in which a web of 30 wt % hollow PET fiber and 70 wt % LPET fiber was used for the core nonwoven fabric forming the core layer 2, and the bending modulus gradient was less than 20 N / 50 mm / cm. In Test Example 10, the content of LPET fiber in the skeleton nonwoven fabric was less than the content of LPET fiber in the core nonwoven fabric, and it is presumed that this was due to insufficient rigidity of the skeleton layers 3 sandwiching both the upper and lower surfaces of the core layer 2.

[0068] (Test Examples 11 to 14) Test Examples 11 to 14 were fabricated using a core material layer 2 containing 30 wt% hollow PET fiber, 70 wt% LPET fiber, and a surface density of 400 g / m 2 Web penetration of 80 strands / cm 2 The core nonwoven fabric was needle-punched. Each of the skeletal layers 3 above and below the core layer 2 was made of 30 wt % PET fiber, 70 wt % LPET fiber, and a surface density of 200 g / m 2The skeletal nonwoven fabric was needle-punched with a specified penetration number from the top and bottom sides to integrate the skeletal layer 3, the core layer 2, and the skeletal layer 3. The penetration number (needle density) from the top and bottom sides was set to 60 needles / cm2. In Test Example 11, the skeletal nonwoven fabric was needle-punched with a penetration number of 200 needles / cm2. 2 Test Examples 12 to 14 are test examples in which needle punching treatment was performed, and the bending elasticity gradient was 20 N / 50 mm / cm or more, but because the penetration number was small, it was at the limit. 2 (Test Example 12), penetration number 600 / cm 2 (Test Example 13), penetration number 980 / cm 2 This is a test example in which needle punching was performed (Test Example 14), and the bending elasticity gradient was 20 N / 50 mm / cm or more. The more the penetration number increased, the larger the value of the bending elasticity gradient (Penetration number 980 / cm 2 It was confirmed that the bending elasticity gradient was 25 N / 50 mm / cm or more (Test Example 14).

[0069] (Second embodiment) The second embodiment will be described in more detail below with reference to examples. As shown in Figure 2, an automobile ceiling material 1A of the second embodiment is formed by laminating a film layer 4 on the upper or lower surface side of the automobile ceiling material 1 of the first embodiment. In the second embodiment, the automobile ceiling material 1 of the first embodiment is referred to as ceiling material A or ceiling material B, and details thereof are shown in Table 6. Details of the PET fiber, hollow PET fiber, and LPET fiber used in the second embodiment are shown in Table 5.

[0070]

[0071]

[0072] Details of the film layer 4 laminated on the upper surface of the automobile ceiling material 1A are shown in Table 7, details of the decorative layer 5 laminated on the lower surface (inside the vehicle compartment) of the automobile ceiling material 1A are shown in Table 10, and details of the film layer 4 laminated on the lower surface of the automobile ceiling material 1A are shown in Table 9. In addition, details of the adhesive layer 6 that adheres the film layer 4 or the decorative layer 5 to the ceiling material (the automobile ceiling material 1 of the first embodiment) are shown in Table 8, and details of the multilayer film in which LPET of the adhesive layer 6 is laminated on the film layer 4 are shown in Tables 7 and 9, respectively.

[0073]

[0074]

[0075]

[0076]

[0077] The automotive ceiling material 1A of the second embodiment is obtained by laminating a film layer 4 on the upper or lower surface of the automotive ceiling material 1 of the first embodiment, and, if necessary, laminating a decorative layer 5 on the lower surface. The automotive ceiling material 1A of the second embodiment was subjected to a preliminary bonding treatment at 190°C for 2 minutes and processed into a molding nonwoven fabric for the automotive ceiling material 1A. The processed molding nonwoven fabric was measured for its bending modulus gradient and evaluated. Test examples of the automotive ceiling material 1A of the second embodiment were evaluated by changing the types of the ceiling material, film layer 4, decorative layer 5, and adhesive layer 6 (Tables 6 to 10). Details of the evaluation are shown in Table 11. Note that Test Examples 15 to 22 are working examples.

[0078]

[0079] (Test Examples 15 to 17) Test Examples 15 to 17 are test examples of a non-breathable automobile ceiling material 1A in which a film layer 4 made of a PET film is laminated on the upper surface side of the automobile ceiling material 1 (ceiling material A) of the first embodiment, which has a skin layer on the lower surface side (inside the vehicle cabin), and in which a decorative layer 5 is not laminated on the lower surface side. The lower surface side is decorated by the skin layer of the ceiling material A. Test Example 15 is a test example of an automobile ceiling material 1A in which a PET film A consisting only of a PET film is used as the film layer 4, and the film layer 4 is laminated to the ceiling material A using an adhesive layer 6 of an LPET web. Test Example 16 is a test example of an automobile ceiling material 1A in which a PET film A consisting only of a PET film is used as the film layer 4, and the film layer 4 is laminated to the ceiling material A using an adhesive layer 6 of an LPET film. Test example 17 is a test example of an automobile ceiling material 1A in which a PET film is laminated to a ceiling material A by heat-sealing the LPET film (adhesive layer 6) laminated to the PET film B, which is a PET film of the film layer 4 and an LPET film of the adhesive layer 6. Test examples 15 to 17 each had a bending elasticity gradient of 20 N / 50 mm / cm or more, and were strong.

[0080] (Test Examples 18-20) Test Examples 18-20 are test examples of a non-breathable automobile ceiling material 1A in which a film layer 4 made of a PET film is laminated on the upper surface of the automobile ceiling material 1 (heading material B) of the first embodiment that does not have a skin layer, and a decorative layer 5 is laminated on the lower surface. Test Example 18 is a test example of an automobile ceiling material 1A in which a PET film A consisting only of a PET film is used as the film layer 4, and the film layer 4 is laminated on the upper surface of ceiling material B using an adhesive layer 6 of an LPET web, and a decorative layer 5 made of a knit skin is laminated on the lower surface of ceiling material B using an adhesive layer 6 of the LPET web. Test Example 19 is a test example of an automobile ceiling material 1A in which a PET film A consisting only of a PET film is used as the film layer 4, and the film layer 4 is laminated on the upper surface of ceiling material B using an adhesive layer 6 of the LPET film, and a decorative layer 5 made of a printed skin is laminated on the lower surface of ceiling material B using an adhesive layer 6 of the LPET film. Test example 20 is a test example of an automobile ceiling material 1A in which a PET film B, in which an LPET film of adhesive layer 6 is laminated to a PET film of film layer 4, is used to laminate the LPET film (adhesive layer 6) laminated to the upper surface of ceiling material B by heat sealing, and a decorative layer 5 made of a knit skin is laminated to the lower surface of ceiling material B using the adhesive layer 6 of the LPET web. Test examples 18 to 20 each had a bending modulus gradient of 20 N / 50 mm / cm or more, and were strong.

[0081] Test Example 21 is a test example of a non-breathable automobile ceiling material 1A in which a decorative layer 5 made of a printed skin is laminated by heat fusion to the underside of the automobile ceiling material 1 (heading material B) of the first embodiment that does not have a skin layer, using a three-layer film in which LPET adhesive layers 6 are laminated on both sides of the film layer 4. Test Example 21 had a bending elasticity gradient of 20 N / 50 mm / cm or more and was strong.

[0082] Test Example 22 is a test example of a breathable automobile ceiling material 1A in which a decorative layer 5 made of a knitted skin is laminated by heat fusion using an LPET web on the underside of the automobile ceiling material 1 (heading material B) of the first embodiment that does not have a skin layer. Test Example 22 had a bending modulus gradient of 20 N / 50 mm / cm or more and was strong.

[0083] (Third Embodiment) The third embodiment will be described in further detail below with reference to examples. As shown in FIG. 3, the automobile ceiling material 1B of the third embodiment is formed by laminating a nonwoven fabric layer 7 on the upper surface of the automobile ceiling material 1A of the second embodiment. In the third embodiment, as in the second embodiment, the automobile ceiling material 1 of the first embodiment is referred to as ceiling material A or ceiling material B, and the details thereof are the same as those listed in Table 6. Details of the nonwoven fabric layer 7 laminated on the upper surface of the automobile ceiling material 1B of the third embodiment are listed in Table 12. The adhesive layer 6 that bonds the nonwoven fabric layer 7 to the automobile ceiling material 1B is the same as the adhesive layer A and adhesive layer B listed in Table 8.

[0084]

[0085] The automobile ceiling material 1B of the third embodiment is obtained by laminating a nonwoven fabric layer 7 on the upper surface of the automobile ceiling material 1A of the second embodiment, and then performing a preliminary bonding process at 190°C for 2 minutes to process the nonwoven fabric for molding into the automobile ceiling material 1B. The processed molding nonwoven fabric was evaluated by measuring the bending modulus gradient. Details of the test examples are shown in Table 13. Test examples 23 to 26 are working examples.

[0086]

[0087] (Test Examples 23 to 26) Test Example 23 is a test in which an adhesive layer A (30 g / m) was applied to the upper surface of Test Example 15 (the automobile ceiling material 1A of the second embodiment). 2 A nonwoven fabric layer A (60 g / m PET web) is placed on the nonwoven fabric layer B (60 g / m PET web). 2 Test Example 24 is a test example of a non-breathable automobile ceiling material 1B in which an adhesive layer B (30 g / m PET spunbond nonwoven fabric) is laminated on the upper surface of Test Example 16 (the automobile ceiling material 1A of the second embodiment). 2A nonwoven fabric layer B (30 g / m PET film) is placed between the nonwoven fabric layer B and the nonwoven fabric layer C. 2 Test Example 25 is a test example of a non-breathable automobile ceiling material 1B in which a nonwoven fabric layer B is laminated via an adhesive layer A on the upper surface side of Test Example 18 (the automobile ceiling material 1A of the second embodiment). Test Example 26 is a test example of a non-breathable automobile ceiling material 1B in which a nonwoven fabric layer A is laminated via an adhesive layer B on the upper surface side of Test Example 19 (the automobile ceiling material 1A of the second embodiment). Test Examples 23 to 26 each had a bending modulus gradient of 20 N / 50 mm / cm or more and were strong. When parts were attached to the automobile ceiling material 1B with hot melt, the resin constituting the hot melt was able to penetrate into the porous pores of the nonwoven fabric layer 7, ensuring adhesive strength.

[0088] REFERENCE SIGNS LIST 1 Automotive ceiling material 1A Automotive ceiling material 1B Automotive ceiling material 2 Core material layer 3 Skeleton layer 4 Film layer 5 Decorative layer 6 Adhesive layer 7 Nonwoven fabric layer

Claims

1. An automobile ceiling material in which nonwoven fabrics formed from fibers are laminated and heat-treated, comprising a core layer made of a core nonwoven fabric, and skeletal layers made of skeletal nonwoven fabric laminated on the top and bottom surfaces of the core layer, wherein the core nonwoven fabric is made of PET fibers and LPET fibers, and the skeletal nonwoven fabric is made of the PET fibers and the LPET fibers, and the content of the LPET fibers in the skeletal nonwoven fabric is equal to or greater than the content of the LPET fibers in the core nonwoven fabric.

2. The automobile ceiling material according to claim 1, characterized in that the content of the LPET fibers in the framework nonwoven fabric is 60 to 90 mass %.

3. The automobile ceiling material according to claim 1, characterized in that the PET fibers contained in the core nonwoven fabric contain hollow PET fibers.

4. The automobile ceiling material according to any one of claims 1 to 3, characterized in that a film layer is laminated on the upper or lower surface side.

5. A method for manufacturing an automobile ceiling material according to any one of claims 1 to 3, characterized in that the skeletal nonwoven fabric forming the skeletal layer, the core nonwoven fabric forming the core layer, and the skeletal nonwoven fabric forming the skeletal layer are laminated together and entangled by needle punching.

6. The method for manufacturing an automobile ceiling material according to claim 5, wherein the needle punching is performed from the upper surface side and the lower surface side, respectively.

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