JPS63126955A - Production of fibrous sheet composite - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a molded article that is lightweight and has excellent rigidity, heat resistance, shapeability, sound absorption, etc., and a fibrous sheet that is particularly useful as a ceiling material for automobiles. The present invention relates to a method for producing a composite.

(Prior Art) A molded ceiling, which is one of the interior materials of an automobile, is made of cardboard or various resin foams. Cardboard is lightweight and inexpensive, but since the only means of shaping is compression, it has poor formability and cannot be shaped into delicate shapes.

Furthermore, it has the disadvantage of poor shape retention due to its hygroscopic properties. Therefore, resin foams are widely used. For example, JP-A-58-71154 and JP-A-58-
No. 2811 discloses a molded ceiling using modified polystyrene foam. Such molded bodies are obtained by foaming resin and molded into the desired shape, so they have excellent formability.The molded bodies obtained are relatively strong and lightweight, and have excellent heat insulation, heat resistance, and elasticity. (Excellent cushioning properties). However, since thermoplastic resin is used, the dimensional stability and rigidity at high temperatures are poor.

Furthermore, since closed-cell foam is used to obtain a heat-insulating effect, sound is reflected on the surface, making it impossible to obtain a sufficient sound-absorbing effect. In order to improve the rigidity of such molded ceilings, reinforcing materials are laminated, and in order to obtain a sound absorption effect, sound absorbing materials are laminated or through holes are provided in the base material (
JP-A-55-11947, JP-A-53-14074, and JP-B-Sho 57-60944), the manufacturing process is complicated and costs are high. Another drawback is that the weight of the molded ceiling itself increases, reducing the fuel efficiency of the vehicle.

(Problems to be Solved by the Invention) The present invention eliminates the above-mentioned conventional drawbacks, and aims to provide lightweight, rigid, shapeable, heat-resistant, heat-insulating, and sound-absorbing An object of the present invention is to provide a method for producing a composite body suitable for a molded ceiling of an automobile, which has excellent elasticity and cushioning properties, and also has excellent rigidity and dimensional stability at high temperatures.

(Means for Solving the Problems) The method for manufacturing the m-fibrous sheet composite of the present invention includes glass la
A nonwoven fabric sheet containing glass fibers, organic fibers, and, if necessary, a binder thereof is laminated on one or both sides of a nonwoven fabric base material containing fibers and organic fibers, and this laminate is placed in the nonwoven fabric base material. Organic! ! or the melting point of the organic #i#& of the nonwoven fabric sheet, whichever is higher, to melt these organic fibers and form a droplet-shaped melt,
This is a method in which glass fibers forming a skeleton are bonded to each other at their intersections using the droplet-shaped melt, thereby achieving the above object. 1 The set diameter of the glass fiber used in the present invention is 5 to 30μ
m and the fiber length is 5 to 200M. If the fiber diameter and fiber length of the inorganic fibers are below the above lower limit values, the rigidity of the nonwoven fabric will be insufficient, and the shape of the face material will not be maintained when the base material is heated, which will be described later, and the resulting composite will deform. It is also inferior in rigidity. vice versa,
If the fiber diameter or fiber length exceeds the above-mentioned upper limit, the delicate shape of the molded ceiling of an automobile cannot be imparted. In addition, the fiber diameter of the organic fiber used for the base material is 3 to 50 μm, and the fiber length is 5 to 50 μm.
It is 200m. If the fiber diameter and fiber length of the organic fibers are below the above-mentioned lower limit, the molten droplets will become small units in the heating/forming process described below, making it insufficient to bond the glass fibers together. On the other hand, when the upper limit is exceeded, the melted droplets become large units, the number of bonding points decreases, and a composite with sufficient strength cannot be obtained.

The nonwoven fabric that is the base material used in the present invention contains the glass fibers and organic m#: in a weight ratio of 1°:1 to 1:5. If the amount of glass ms is excessive and the amount of organic fiber is too small, it will be difficult to form it into a nonwoven fabric, and when preparing a molded article under heat and pressure, the binder effect derived from the organic fibers will be It becomes difficult to obtain. vice versa,
If the amount of organic fiber is excessive, the strength of the resulting composite will be improved, but if the amount of glass fiber is too little, the porosity of the composite will be reduced. As a result, sound absorption performance deteriorates.

The organic fiber used for the base material of the present invention and the organic fiber material used for the nonwoven fabric sheet have a melting point of 70 to 250.
C, preferably from 90 to 250 C'', including polyolefins such as polyethylene and polypropylene; polyesters; polyamides; polystyrene; polyvinyl chloride; and polyurethane.

As the binder (binding agent) for the nonwoven fabric sheet, the above-mentioned resins, adhesives, etc. are used as necessary.

When using the above resin as the binder, select a resin with a lower melting point than the organic fibers contained in the nonwoven fabric sheet, and heat the resin at a temperature higher than the melting point of the binder component and lower than the melting point of the organic fibers contained in the nonwoven fabric sheet. and organic fibers to form a sheet. In addition to the above-mentioned organic fibers used in the base material and the organic fibers used in the nonwoven fabric sheet of the present invention, composite fibers made of 281 or more of these materials, such as composite fibers made of 281 or more of these materials, such as relatively high melting point resins and low melting point resins. Fibers coated with vine are also used. Examples of such composite fibers include fibers in which polypropylene is coated with polyethylene, fibers in which high-melting point polyester is covered with low-melting point polyester, and the like. When the melting point of the organic fiber is lower than 79C', the resulting molded product softens when exposed to high temperatures, resulting in a decrease in its ability as a binder, which will be described later, resulting in poor dimensional stability of the molded product. On the other hand, if the melting point exceeds 250C, high temperatures are required during molding, and the molding time becomes longer, resulting in higher costs.

The nonwoven fabric sheet used in the present invention preferably has a thickness of 5 mm or less and a density of α59/ad or less. Thickness is 5
If it is thicker than u, it becomes difficult for heat to be transmitted to the inside during molding, and a large amount of heat is required, which is disadvantageous in terms of cost. Moreover, when the density is 0.59/m or more, the molded body becomes heavy, and the porosity of the molded body decreases, so that the sound absorption coefficient of the surface layer also decreases. If the nonwoven fabric sheet exceeds the strength of glass fibers, organic fibers, or if necessary, the strength of the sheet will be weakened and it will be difficult to handle it as a sheet, resulting in a decrease in workability. Another disadvantage is that the increase in the number of glass fibers reduces the shapeability of the composite.

The nonwoven fabric that is the base material used in the present invention is prepared using the above-mentioned glass fibers and organic fibers by a normal nonwoven fabric manufacturing method. For example, first, glass fibers commercially available in the form of yarn chops, roving chops, etc. are opened.

Organic fibers are similarly opened to form filaments, and after these glass fibers (inorganic fibers) and organic fibers are blended with air to thoroughly mix the fibers, compression molding is performed to obtain a nonwoven fabric. A card machine or the like may also be used.

The density of such a nonwoven fabric is α01 to q2.

If it is less than 0.01, it will be difficult to maintain the shape as a nonwoven fabric, and the strength of the resulting composite will also decrease. α2
If the weight exceeds 100%, the weight of the entire composite becomes large, making it unsuitable for use as a molded ceiling for automobiles. The thickness of the nonwoven fabric needs to be thicker than the thickest part of the target composite, and is usually 5 to 100 m. If the strength is lower than 5, the strength of the molded ceiling as a whole is insufficient, and the strength is 10.
If it exceeds 0 tm, it becomes difficult for heat to be transmitted to the center during heating, which will be described later, so a large amount of heat is required.

The nonwoven fabric sheet is laminated on at least one surface of the base material thus obtained, and used as a molding material and heated to a temperature equal to or higher than the melting point of whichever has a higher melting point of the organic fibers of the base material or the nonwoven fabric sheet. The heating temperature varies depending on the material of the organic fibers contained, the blending ratio of inorganic fibers and organic fibers, the thickness of the base material, etc., but is usually 5 to 100C higher than the melting point of the organic fibers.
High temperatures are used. Next, this base material is pressure-molded using a mold having a desired shape. Compression time is 5 seconds to 20 minutes.

An interior decorative material made of textile fabric, nonwoven fabric, plastic sheet, etc. is adhered to the surface of the automobile ceiling composite obtained by such a method. The composite and the interior decorative material may be laminated, heated, and integrally formed. The composite obtained by the present invention has a high porosity and may allow gas to pass through the molded body. For example, in order to prevent the ceiling from staining due to cigarette smoke, it is also recommended to apply an air-blocking sheet to the surface of the molded product. Such air-blocking sheets include
For example, a plastic sheet or a high-density nonwoven fabric is used. This air-blocking sheet can also be integrally molded with the base material in the same way as the decorative material. For example, by laminating the air-blocking sheet on one side of the composite and the interior decorative material on the other side, and heating and compression molding this laminate, the air-blocking sheet and the interior decorative material are layered on the surface. A MY sheet molded article having 11 fibers is obtained.

The fibrous sheet composite is obtained by laminating, heating, and compression molding a nonwoven fabric sheet on at least one surface of a relatively low-density nonwoven fabric base material made of glass fibers and organic fibers. It is thought that most of the organic fibers in such base materials and nonwoven fabric sheets are melted during the heating process and become water droplets that adhere to the glass fibers. When the glass fibers are compressed in the compression process using the mold, it is considered that there is a high probability that the molten resin in the form of water droplets also moves on the glass fibers and stays at the contact point between the fibers. When the temperature falls, the resin derived from organic 81& hardens and acts as a binder to firmly bond fibers (mainly glass!) together. In this manner, the resulting molded product has glass fiber as its main skeleton, and since the glass fiber shell is fixed by the resin, it has excellent rigidity and shape retention. Since glass & rim is used, its thermal stability is superior to that of conventional heat shaping.

Furthermore, since the nonwoven fabric sheet used in the present invention is in the form of a sheet, it is easy to handle and can sufficiently improve the poor workability when using conventional glass m#: or adhesives.

The porosity (density) differs depending on the part, but for example, the peripheral part of an automobile ceiling has a high density because it is sufficiently compressed and molded, and the central part has a low density because the degree of compression is small. The high-density portion has particularly high rigidity, while the low-density portion has external force resistance and has a high sound absorption effect.

As described above, the composite obtained by the present invention has the various excellent properties mentioned above, so that it can be used as a reinforcing material,
Sound absorbing materials, cushioning materials, etc. are not required. Therefore, the process for manufacturing the automobile ceiling is simplified, and the weight of the ceiling itself is also reduced.

Hereinafter, the present invention will be explained with reference to the drawings.

As shown in FIG. 1, the fibers 2 contained in a fiber supply container 1 are supplied to a card machine 5, and after being sufficiently mixed, they are formed into a continuous non-woven fabric base material 6, which is made from glass fibers and organic fibers. After the nonwoven fabric sheets 3 are laminated, they are wound up by a winding machine 7 to form a molding material 4. The rolled material 4 is cut into a desired shape and size.

Compression molding was performed in a molding die 11 to form a fibrous material (Example) The present invention will be described below with reference to Examples.

Example 1 Production of composite glass fiber #, (diameter Loμms fiber length 50-100w
tx) organic fiber, polypropylene fiber (diameter 13 μm, i! fiber length 50-10 (1 m, melting point 1
60C') Non-woven fabric sheet, Donami Paper PP paper interior decorative material, polyester non-woven fabric (thickness 15B) The above glass fibers and organic fibers (weight ratio 1:1) were uniformly mixed by a card machine, thickness 20++W, density (No. 104 nonwoven fabric substrates were obtained.

Nonwoven fabric sheets were laminated on both surfaces of this base material to obtain a molding material. This material has a width of 1150 ts and a length of 1400 ts.
The material was cut into a length of m, and the above-mentioned interior decoration material of the same size was laminated thereon, and the periphery was pinched with a clamp. 20 pieces of this laminate
After heating with hot air at 0C for 3 minutes, immediately reduce the temperature to 30C'.
Compression molding was performed for 1 minute using a mold with a compression force of 1 kq/cd. This mold was designed to have a minimum thickness of 3.0 mm and a maximum thickness of 8.0 mm, and the obtained composite substantially corresponded to the shape of this mold.

[F]) Performance evaluation of composite: After holding the composite obtained in section ^ in a hot air oven at 95C for 20 hours, the amount of displacement (sag) was measured. A sample piece having a thickness of 6 m, width of 50 m, and length of 150 m was cut from the composite obtained in section (5), and its bending strength was evaluated. First, the sample piece is placed on a pair of supports spaced apart by Zoo*.

Next, force is applied to the center of this sample piece at a speed of 50 W/min. Then, the weight of the sample piece when it was bent was measured. Furthermore, a sample piece with a thickness of 8 mm and a diameter of 90 mm was cut from the molded body obtained in the above section, and the sound absorption coefficient at 00 Hz was measured using the subgenus incidence sound absorption coefficient measurement method.

The respective results are shown in the table below. In the table below, the porosity of the composite was calculated based on the average thickness of six fins. Composite weight does not include decorative material weight. In terms of bending strength,
○ indicates LOk (1/d or more, △ indicates 9.9 to 6 kg)
/ d, and × indicates toy 9 / d or less. The results of Examples 2 to 4 and Comparative Examples 1 to 6 are also shown below.

Example 2 The same as Example 1 was used except that a nonwoven fabric sheet having a thickness of 2 mm and a density of α099/d was used.

Example 3 The weight ratio of glass fiber and organic fiber was 5:l, and the thickness was 60
The procedure was the same as in Example 1 except that a nonwoven fabric having a density of CL015 and a density of CL015 was prepared.

Example 4 The weight ratio of glass fiber and organic fiber was 1:5, and the thickness was 20
The procedure was the same as in Example 1, except that a nonwoven fabric base material having a density of 0.04 and a density of 0.04 was prepared.

Comparative Example 1 This was the same as in the previous example except that a non-woven fabric sheet was not used.

(Effects of the Invention) Since the method for producing a fibrous sheet composite of the present invention has the above-described structure, it is lightweight and rigid, and has excellent formability, heat resistance, heat insulation, sound absorption, and cushioning properties. A fibrous sheet composite having excellent rigidity and dimensional stability at high temperatures can be obtained at low cost through a simple manufacturing process.

Such a fibrous sheet composite is suitable for automobile ceiling materials. When the fibrous sheet composite obtained by the present invention is used as an automobile ceiling material, reinforcing materials, cushioning properties, sound-absorbing materials, etc. conventionally required for automobile ceilings become unnecessary. The ceiling material itself is also lighter, which reduces fuel consumption. The fibrous sheet composite obtained by the present invention can be used not only as a ceiling material for automobiles but also in many fields such as ceiling materials for houses and ships, and building materials for heat insulation.

[Brief explanation of the drawing]

FIGS. 1 and 2 are front views sequentially explaining the steps of the present invention. DESCRIPTION OF SYMBOLS 1... Fiber supply container, 2... Fiber, 3... Nonwoven fabric sheet, 4... Material, 5... Card machine, 6...
Nonwoven fabric body, 11...Molding mold 1, 1p72z...
Belt conveyor, 51...Heating furnace

Claims (5)

[Claims] 1. A nonwoven fabric sheet containing glass fibers, organic fibers, and, if necessary, a binder thereof is laminated on one or both sides of a nonwoven fabric base material containing glass fibers and organic fibers, and this laminate is used as the nonwoven fabric base material. The organic fibers are heated to a temperature higher than the melting point of the organic fibers in the nonwoven fabric sheet or the melting point of the organic fibers of the nonwoven fabric sheet, whichever is higher, to melt these organic fibers into a droplet-shaped melt, and the droplet-shaped melt forms a skeleton. A method for producing a fibrous sheet composite, which comprises bonding glass fibers together at their intersection points. 2. The non-woven fabric sheet has a thickness of 5 mm or less and a density of 0.5 g.
2. The method for producing a fibrous sheet molded article according to claim 1, wherein the fibrous sheet molded body has a particle diameter of /cm^3 or less. 3. Claim 1, wherein the weight ratio of glass fibers and organic fibers constituting the nonwoven fabric base material is 10:1 to 1:5, and the porosity after pressurization and molding is 80 to 99.5%. A method for manufacturing the fibrous sheet composite described above. 4. The method for producing a fibrous sheet composite according to claim 1, wherein the organic fibers of the nonwoven fabric base material and the organic fibers of the nonwoven fabric sheet are synthetic resins with a melting point of 70 to 250°C. 5. The fiber lengths of the glass fibers and organic fibers of the nonwoven fabric base material are each 5 to 200 mm, and the density of the base material is 0.0
The method for producing a fibrous sheet composite according to claim 1, wherein the fibrous sheet composite has a thickness of 1 to 0.2 mm and a thickness of 5 to 100 mm.