JPH06184901A - Composite fiber assembly - Google Patents

Abstract

PURPOSE:To provide a composite fiber assembly having such thickness as to be consistently high in mechanical strength despite varying in its weight and good in press formability. CONSTITUTION:The composite fiber assembly is such that numerous glass fibers including those oriented in the thickness direction are mutually, partly bound through high-density polyethylene and there are numerous fine voids throughout. The thickness T (mm) of the assembly, depending on its weight W (kg/m<2>), satisfies the following relationships: when 0.4<=W<=0.9, 4W-0.5<=T<=5W+1, and when 0.9W<=1.7, 6W-2.3<=T<=8W-1.7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber composite used for interior materials for automobiles and interior materials for construction.

[0002]

2. Description of the Related Art Generally, the above interior materials are required to be lightweight and have excellent properties such as rigidity, heat resistance and moldability. Conventionally, as this type of material, a fiber composite is known in which a large number of inorganic fibers including those oriented in the thickness direction are partially bonded to each other with a thermoplastic resin and have a large number of voids throughout. (Japanese Patent Laid-Open No. 1-1565)
No. 62).

[0003]

When the above-mentioned conventional fiber composite is press-molded, it is usually heated and then pressed. When the strength of the molded products obtained by press molding was compared for the fiber composites of various thicknesses before heating, the strength decreased when the thickness of the fiber composites was increased. It turned out to do. Weight of 700
FIG. 1 shows the result of examination on the g / m ² fiber composite.

When molding the above-mentioned fiber composite, first, the thermoplastic resin is heated to a temperature above its melting point, but when the thermoplastic resin is melted, a large number of inorganic fibers are oriented in the thickness direction. Because of the inclusion, these restoring forces act to expand the fiber composite and increase its thickness. However, it has been found that when the thickness of the fiber composite is reduced, the fiber composite does not expand sufficiently even when heated at a certain thickness as a boundary, and the thickness does not increase so much. In the case of press molding, if the thickness is insufficient, there is a cavitation that the molding cannot be performed accurately according to the shape of the mold.

An object of the present invention is to provide a fiber composite having a thickness which is always high in strength even when the weight is changed and has good press moldability.

[0006]

The fiber composite according to the present invention comprises a large number of inorganic fibers, which are partially bonded to each other with a thermoplastic resin, including a plurality of inorganic fibers including those oriented in the thickness direction. In a fiber composite having various voids, when the thickness T (mm) is 0.4 ≦ W ≦ 0.9 as a function of weight W (kg / m ² ), 4W−0.5 ≦ T ≦ 5W +
When 1 0.9 <W ≦ 1.7, 6W−2.3 ≦ T ≦ 8W−
It is characterized by being in the range of 1.7.

The reason why the thickness of the fiber composite is limited to the above range is as follows. That is, the limit thickness of the fiber composite in which the strength decreases decreases depending on the weight of the fiber composite, and the larger the weight, the greater the limit thickness. Therefore, the appropriate thickness T (mm) in this case is the weight W (kg /
Since it is a function of m ² ), the following equation is obtained.

When 0.4 ≦ W ≦ 0.9, T ≦ 5W + 1 0.9 <W ≦ 1.7, T ≦ 8W-1.7 Further, the thickness is satisfied at the time of heating during molding. Increase as possible
Not fiber Fiber composite limit thickness is the weight of fiber composite
The limit thickness increases as the weight increases.
Become. Therefore, the appropriate thickness T (mm) in this case is also heavy.
Quantity W (kg / m ²) Function,
It

When 0.4 ≦ W ≦ 0.9, 4W−0.5 ≦ T 0.9 <W ≦ 1.7, 6W−2.3 ≦ T As the inorganic fiber, glass fiber, lock Wool, ceramic fibers, carbon fibers and the like can be mentioned, and the length thereof is preferably 5 to 200 mm from the viewpoint of moldability of the mat-like material described later,
It is more preferable that 70% by weight or more of 50 to 100 mm is contained. Further, when the thickness is thin, the mechanical strength is lowered, and when the thickness is thick, the weight is heavy and the bulk density is small. Therefore, the thickness is preferably 3 to 30 μm, more preferably 5 to 5 μm.
It is 20 μm.

Examples of the thermoplastic resin include polyethylene, polypropylene, saturated polyester, polyamide, polystyrene, polyvinyl butyral and polyurethane. When the fiber composite is obtained from the mat-like material described later, it is necessary to laminate the thermoplastic resin as a film on both surfaces thereof. The thickness of this film can be appropriately determined by the ratio with the inorganic fibers constituting the mat-like material.

Fiber composites are obtained from mats,
Examples of the method for producing the mat-like material include a method in which inorganic fibers are supplied to a card machine, defibrated, mixed, and needle punched. Needle punch density is 1 cm ²
30 to 200 locations are preferable. The inorganic fibers in the needle-punched portion are oriented in the thickness direction of the mat-like material. In order to bond the inorganic fibers and increase the bulk of the mat-like material, thermoplastic organic fibers such as polyethylene, polypropylene, saturated polyester, polyamide and polyacrylonitrile are contained in the mat-like material in an amount of 10 to 30% by weight.
It is preferable to add it. Further, in order to bond the inorganic fibers uniformly, a powdery thermoplastic resin may be mixed at the time of defibration, or a powdery thermoplastic resin or an emulsion of the thermoplastic resin may be added to the mat-like material after the mat-like material is formed. May be sprayed.

Next, a thermoplastic resin film is laminated on both surfaces of the obtained mat-like material, the laminate is heated to the melting temperature of the thermoplastic resin, and pressurized and compressed while maintaining this temperature. The pressure at this time is preferably 0.1 to 5 kg / cm ² , and the pressing time is preferably 1 to 30 seconds.

Finally, while keeping the above temperature, the compression is released and both surfaces of the mat-like material are vacuum-sucked to be inflated, and the thickness is forcibly changed so that the relationship between the weight and the thickness satisfies the above range. Increase.

In the above process, the thermoplastic resin film is melted and compressed to impregnate the matte material with the molten resin. When the inorganic fibers are mixed with a fibrous or powdery thermoplastic resin, these are also melted to bond the inorganic fibers. At this time, if the compression is released before the molten resin is uniformly impregnated into the mat-like material by controlling the pressure and the pressurization time, the molten resin is more densely impregnated in the surface portion than in the inside, and a large number of inorganic It is preferable that the fibers are partially bonded to each other with a thermoplastic resin, a large number of pores are formed on the surface, and a fiber composite having a large number of fine voids throughout is obtained.

Although it may be shaped during heating and pressing, it may be formed into a plate-like shape during heating and pressing and then heated and pressed again before use to shape it. Especially when it is used as a ceiling material for automobiles, it is made into a plate-like body, and a foam or a cosmetic skin material is laminated and supplied to a mold for a different shape,
It is preferable to heat-bond and shape-form.

The ratio of the inorganic fiber to the thermoplastic resin is such that when the amount of the thermoplastic resin is small, the number of joints is small, the mechanical strength of the fiber composite is low, and when the ratio is large, the porosity is low. A ratio of 1: 4 to 4: 1 is preferred. When the density of the fiber composite increases, it becomes heavier, and when it decreases, the mechanical strength decreases, so 0.01 to 0.2 g / cm.
² is preferable, and the total porosity is 70 to 98.
% Is preferred. Furthermore, the thermoplastic resin bonding the inorganic fibers is more densely distributed on the surface than in the interior of the fiber composite, and the porosity of the surface is lower than that of the interior, but the porosity of the surface is Is 50 to 95% and the internal porosity is preferably 85 to 99%.

A film, a foamed sheet, a metal plate or the like is laminated on the fiber composite of the present invention, or an adhesive or an adhesive is laminated on the surface of the fiber composite so that the fiber composite can be easily adhered to other articles. You may also laminate polyethylene foam, polypropylene foam, polyurethane foam, foam with open or closed cells such as rubber foam or non-woven fabric, woven cloth, vinyl chloride leather or other cosmetic skin material. Good.

Although there is an unclear reason why the thickness increases when the fiber composite of the present invention is heated, the inorganic fibers are bent by compression by the above-mentioned needle punching treatment. It is presumed that this is due to the attempt to restore the original state due to melting.

[0019]

Since the present invention has the above-mentioned constitution, it has sufficient strength in relation to each weight of the fiber composite and sufficient moldability at the time of heating during heat molding. It can be of a thickness that guarantees an increase in thickness.

[0020]

EXAMPLES Next, examples of the present invention will be described together with comparative examples.

Example 1 In this example, a fiber composite in which a number of glass fibers, including those oriented in the thickness direction, are partially bonded to each other with high density polyethylene and have a number of fine voids throughout Since it is a body and its weight is 0.6 kg / m ² , it has a thickness of 3.5 mm.

This fiber composite is manufactured as follows. That is, length 50 mm, diameter 1
3 μm glass fiber and 50 mm long, 10 μm diameter polypropylene fiber were supplied to a card machine at a weight ratio of 3: 1, and after defibration, 100 points were punched per 1 cm ² to obtain a thickness of 6 mm and an average weight of 400 g. A mat-like product having a thickness of / m ² was obtained. 105μ thickness on both sides of mat
m, a high-density polyethylene film having an average weight of 100 g / m ² was laminated, and the obtained laminate was sandwiched between two polytetrafluoroethylene films, heated at 200 ° C. for 3 minutes, and then heated at 200 ° C. 5 kg /
Pressurized with cm ² and compressed to 0.8 mm, while keeping the temperature at 200 ° C., vacuum suction the polytetrafluoroethylene film on both sides in the thickness direction to pull it, expand the laminate to a thickness of 3.5 mm, and then cool. Then, the polytetrafluoroethylene film was peeled off to obtain a fiber composite of the present invention having a thickness of 3.5 mm. The obtained fiber composite is heated again to 200 ° C. to expand in the thickness direction, and the thickness is measured to be 4.0 mm.
And press-mold it so that the bending strength of the molded product is JIS
It measured based on K7221.

Example 2 The fiber composite of this example has a weight of 0.6 kg / m.
Since the thickness is ² , Example 1 is used except that the thickness is 2.3 mm.
Is the same as.

That is, this fiber composite was obtained by the same manufacturing method as in Example 1 except that the heated laminate was expanded to 2.3 mm by vacuum suction.
The bending strength of a molded product press-molded to a thickness of 4 mm after heating was measured in the same manner as in Example 1. Example 3 The fiber composite of this example has a weight of 0.8 kg / m.
² is the same as Example 1 except that the thickness is 4.5 mm.
Is similar to.

This fiber composite is manufactured as follows. That is, length 50 mm, diameter 1
3 μm glass fiber and polypropylene fiber having a length of 50 mm and a diameter of 10 μm were supplied to a card machine at a weight ratio of 3: 1, and after disentanglement, needle punching was performed at 100 points per 1 cm ² to obtain a thickness of 7 mm and an average weight of 550 g. A mat-like product having a thickness of / m ² was obtained. Thickness 130μ on both sides of mat
m, a high-density polyethylene film having an average weight of 125 g / m ² was laminated, and the obtained laminate was sandwiched between two polytetrafluoroethylene films, heated at 200 ° C. for 3 minutes, and then heated at 200 ° C. 5 kg /
Pressurized with cm ² and compressed to 0.8 mm, while keeping the temperature at 200 ° C, vacuum suction the polytetrafluoroethylene film on both sides in the thickness direction and pull it to inflate the laminate to a thickness of 4.5 mm and then cool. Then, the polytetrafluoroethylene film was peeled off to obtain a fiber composite of the present invention having a thickness of 4.5 mm. The obtained fiber composite was heated again to 200 ° C., the thickness was measured, and press molding was performed so that the thickness was 5.0 mm, and the bending strength of the molded product was measured.

Example 4 The fiber composite of this example has a weight of 0.8 kg / m.
^Since it is ² , Example 3 except that the thickness is 3.0 mm
Is similar to.

This fiber composite was obtained by the same manufacturing method as in Example 3 except that the laminate was expanded to 3.0 mm by vacuum suction. Then the thickness is 5.0mm
Was press-molded so that the bending strength of the molded product was measured.

Example 5 The fiber composite of this example has a weight of 1.2 kg / m.
² is the same as Example 1 except that the thickness is 8.0 mm.
Is similar to.

This fiber composite is manufactured as follows. That is, length 50 mm, diameter 1
3 μm glass fiber and polypropylene fiber having a length of 50 mm and a diameter of 10 μm were supplied to a card machine at a weight ratio of 3: 1, and after disentanglement, needle punching was performed at 100 points per 1 cm ² to obtain a thickness of 8 mm and an average weight of 800 g. A mat-like product having a thickness of / m ² was obtained. 210μ thick on both sides of mat
m, a high-density polyethylene film having an average weight of 200 g / m ² was laminated, and the obtained laminate was sandwiched between two polytetrafluoroethylene films, heated at 200 ° C. for 3 minutes, and then heated at 200 ° C. 5 kg /
Pressurized with cm ² and compressed to 1.2mm, while keeping at 200 ° C, vacuum suction the polytetrafluoroethylene film on both sides in the thickness direction to pull it, expand the laminate to a thickness of 7.0mm, and then cool. Then, the polytetrafluoroethylene film was peeled off to obtain a fiber composite. This again 2
It was heated to 00 ° C., the thickness was measured, and press molding was performed so that the thickness was 8.0 mm, and the bending strength was measured.

Example 6 The fiber composite of this example has a weight of 1.2 kg / m.
^Since it is ² , Example 5 except that the thickness is 5.0 mm
Is similar to.

This fiber composite was obtained by the same manufacturing method as in Example 5 except that the laminate was expanded to 5.0 mm by vacuum suction. Then the thickness is 8.0mm
Was press-molded so that the bending strength of the molded product was measured.

Example 7 The fiber composite of this example has a weight of 1.6 kg / m.
² is the same as in Example 1 except that the thickness is 10.0 mm.

This fiber composite is manufactured as follows. That is, length 50 mm, diameter 1
Glass fiber of 3 μm and polypropylene fiber of 50 mm in length and 10 μm in diameter were supplied to the card machine at a weight ratio of 3: 1, and after being defibrated, needle punching was performed at 100 points per 1 cm ² to obtain a thickness of 10 mm and an average weight of 1000 g. / M
² mats were obtained. 315 thickness on both sides of mat
A high-density polyethylene film having a thickness of μm and an average weight of 300 g / m ² was laminated, and the obtained laminate was sandwiched between two polytetrafluoroethylene films, heated at 200 ° C. for 3 minutes, and then heated at 200 ° C. 5kg by the pressed press
After pressurizing with a pressure of / cm ² to 1.6 mm and keeping the temperature at 200 ° C., the polytetrafluoroethylene film on both sides is vacuum-sucked in the thickness direction and pulled to expand the laminate to a thickness of 10.0 mm. After cooling, the polytetrafluoroethylene film was peeled off to obtain a fiber composite. This was heated again to 200 ° C., the thickness was measured, and press molding was performed so that the thickness was 11.0 mm, and the bending strength of the molded product was measured.

Example 8 The fiber composite of this example has a weight of 1.6 kg / m.
Since the thickness is ² , Example 7 except that the thickness is 8.0 mm.
Is similar to.

This fiber composite was obtained by the same manufacturing method as in Example 7 except that the laminate was expanded to 8.0 mm by vacuum suction. Then the thickness is 11.0
Bending strength of the molded product was measured by press molding so as to have a thickness of mm.

Comparative Example 1 The fiber composite of this comparative example has a weight of 0.6 kg / m.
Despite being ² , the same as Example 1 except that the thickness is 4.5 mm.

This fiber composite was obtained by the same manufacturing method as in Example 5, except that the laminate was expanded to 4.5 mm by vacuum suction. After that the thickness is 4.0m
Bending strength of the molded product was measured by press molding so as to have m.

Comparative Example 2 The fiber composite of this comparative example has a weight of 0.6 kg / m.
Despite being ² , the same as Example 1 except that the thickness is 1.5 mm.

This fiber composite was obtained by the same manufacturing method as in Example 1 except that the laminate was expanded to 1.5 mm by vacuum suction. Then, as in Example 1, the material was heated to inflate it to a thickness of 2.9 mm.
The thickness was insufficient for a press machine set to have a thickness of mm, and proper press molding could not be performed.

Comparative Example 3 The fiber composite of this comparative example had a weight of 0.8 kg / m.
Despite being ² , the same as Example 1 except that the thickness is 5.5 mm.

This fiber composite was obtained by the same manufacturing method as in Example 3 except that the laminate was expanded to 5.5 mm by vacuum suction. Then the thickness is 5.0m
It was press-molded so as to have m, and the bending strength of the molded product was measured.

Comparative Example 4 The fiber composite of this comparative example has a weight of 0.8 kg / m.
Despite being ² , the same as Example 1 except that the thickness is 2.0 mm.

This fiber composite was obtained by the same manufacturing method as in Example 3 except that the laminate was expanded to 2.0 mm by vacuum suction. Then the thickness is 2.0m
The bending strength of a molded product press-molded to have a thickness of m was measured.

Comparative Example 5 The fiber composite of this comparative example has a weight of 1.2 kg / m.
Despite being ² , the same as Example 1 except that the thickness is 9.0 mm.

This fiber composite was obtained by the same manufacturing method as in Example 5 except that the laminate was expanded to 9.0 mm by vacuum suction. After that the thickness is 8.0m
It was press-molded so as to have m, and the bending strength of the molded product was measured.

Comparative Example 6 The fiber composite of this comparative example has a weight of 1.2 kg / m.
Despite being ² , the same as Example 1 except that the thickness is 4.0 mm.

This fiber composite was obtained by the same manufacturing method as in Example 5 except that the laminate was expanded to 4.0 mm by vacuum suction. After that, it was heated in the same manner as in Example 5 to inflate it to a thickness of 6.9 mm.
The thickness was not sufficient for the press machine set to m, and proper press molding could not be performed.

Comparative Example 7 The fiber composite of this comparative example has a weight of 1.6 kg / m.
Despite being ² , the same as Example 1 except that the thickness is 12.0 mm.

This fiber composite was obtained by the same manufacturing method as in Example 7 except that the laminate was expanded to 12.0 mm by vacuum suction. Then the thickness is 11.
It was press-molded to have a thickness of 0 mm, and the bending strength of the molded product was measured.

Comparative Example 8 The fiber composite of this comparative example has a weight of 1.6 kg / m.
Despite being ² , the same as Example 7 except that the thickness is 6.0 mm.

This fiber composite was obtained by the same manufacturing method as in Example 7 except that the laminate was expanded to 6.0 mm by vacuum suction. Then, it was heated in the same manner as in Example 7 to be inflated to a thickness of 9.2 mm.
The thickness was insufficient for a press machine set to have a thickness of mm, so that proper press molding could not be performed.

The results of measuring the flexural strength of the molded articles of Examples and Comparative Examples are shown in Table 1 (JIS K722).
1).

[0053]

[Table 1]

[0054]

EFFECTS OF THE INVENTION According to the fiber composite of the present invention, it is possible to obtain a thickness which is always high in strength and has good press formability even if the weight changes.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the thickness of a fiber composite having an average weight of 700 g / m ² and the bending strength of a molded product pressed into a thickness of 4 mm after heating.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location D04H 1/58 A 7199-3B // D06M 15/70 23/16

Claims (1)

[Claims] 1. A fiber composite in which a large number of inorganic fibers including those oriented in the thickness direction are partially bonded to each other with a thermoplastic resin and have a large number of fine voids throughout. T (mm) is weight W (kg /
m ² ), when 0.4 ≦ W ≦ 0.9, 4W−0.5 ≦ T ≦ 5W +
When 1 0.9 <W ≦ 1.7, 6W−2.3 ≦ T ≦ 8W−
A fiber composite characterized by being in the range of 1.7.