JPH05311555A - Production of fiber composite product - Google Patents

Abstract

PURPOSE:To provide a method for producing the fiber composite product excellent in product strength and enabling to uniformize the product strength. CONSTITUTION:The method for producing the fiber composite product comprising successively performing a laminating process for laminating a thermoplastic resin film to a nonwoven mat-like material consisting mainly of inorganic fibers to form a laminate, a heating process for heating the laminate at a temperature above the melting point of the resin component to melt the resin component, a compressing process for compressing the laminate in the melted state and subsequently an expanding process for expanding the resin-melted laminate to increase the thickness of the laminate, is characterized by laminating a paper-like material comprising pulp fibers, a binder and the ground product of the composite product comprising the inorganic fibers and the thermoplastic component to the outside of the thermoplastic resin film or by laminating a paper-like material mixed with thermoplastic resin fibers or power instead of the thermoplastic resin film in the laminating process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is mainly used for automobile interior materials,
For example, the present invention relates to a fiber composite suitably used as a ceiling core material, a door core material, or an interior material for construction.

[0002]

2. Description of the Related Art Generally, an automobile interior material is lightweight,
Materials with excellent properties such as rigidity, heat resistance, sound absorption, and moldability are required. Conventionally, as a method of manufacturing this type of material, for example, a method disclosed in Japanese Patent Laid-Open No. 64-77664 is known. That is, in this method, first, a thermoplastic resin film is laminated on both surfaces of a mat-like material mainly composed of inorganic fibers, the laminated body is heated and then compressed,
The molten thermoplastic resin is impregnated inside the mat-like material.
After that, the thermoplastic resin is expanded in a molten state, the thickness of the laminated sheet is increased, and the laminated sheet is cooled.

In the mat-like material used in this manufacturing method, a large number of fibers are oriented in the thickness direction by needle punching in order to develop the strength in the thickness direction of the product.

[0004]

By the way, the interior materials for automobiles and the interior materials for construction are required to have strength enough to withstand the mounting process.

However, in the case of the above-mentioned conventional manufacturing method, the surface of the mat-like material becomes rough due to a large number of holes and depressions caused by the needle punching process, and the variation in bending strength becomes large. As a result, the product strength is non-uniform, and there arises such a disadvantage that the product is broken at a particularly weak portion.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing a fiber composite which has excellent product strength and is capable of achieving uniform product strength.

[0007]

A method for producing a fiber composite according to the present invention for solving the above-mentioned problems includes a laminate obtained by laminating a film made of a thermoplastic resin on a non-woven mat-like material mainly made of inorganic fibers. A laminating step for forming a layer, a heating step for melting the resin component by heating the laminated body to a temperature equal to or higher than the melting temperature of the resin component, a compression step for compressing the laminated body in this molten state, and the resin component A method for producing a fiber composite which sequentially performs an expanding step of expanding the laminated body in a molten state to increase the thickness of the laminated body, wherein in the laminating step, outside the thermoplastic resin film, A crushed product of a composite composed of an inorganic fiber and a thermoplastic resin component,
A paper-like material composed of pulp fibers and a binder is laminated.

In the laminating step, a pulverized product of a composite composed of inorganic fibers and a thermoplastic resin component, pulp fiber, a binder, and a paper-like material composed of a thermoplastic resin fiber or powder are used without using a thermoplastic resin film. It is to stack things.

The mat-like material used in the present invention is mainly composed of inorganic fibers. Examples of the inorganic fiber include glass fiber and rock wool, and the length thereof is preferably 5 to 200 mm from the viewpoint of forming a mat-like material. In addition, the thickness of the thin film decreases mechanical strength when it becomes thin, and when it becomes thick, it easily breaks during mat formation.
The thickness is preferably 30 μm, more preferably 7 to 20 μm.

Any method may be adopted as the method for producing the mat-like material, and examples thereof include a method in which inorganic fibers are supplied to a card machine, defibrated and mixed to produce a mat-like material. Further, organic fibers made of a thermoplastic resin such as polyethylene, polypropylene, saturated polyester, polyamide and polyacrylonitrile may be added in order to bond the inorganic fibers or to make the mat-like material bulky.

The mat-like material is generally needle punched. At this time, the punch density is 30 per cm ^2.
It is preferable to be carried out at about 100 places. This needle punching treatment is performed in order to increase the compressive strength of the product by orienting a large number of inorganic fibers in the thickness direction of the mat-shaped product in addition to facilitating the handling of the mat-shaped product by entwining the inorganic fibers. ..

In the laminating step, first, the thermoplastic resin films are laminated on both sides of the mat-like material, and the paper-like material is laminated on the outside thereof to form a laminate.

At this time, polyethylene, polypropylene, polyamide, polyester and the like are suitable as the thermoplastic resin film used.

The paper-like material used at this time is a pulverized product of a composite consisting of inorganic fibers and a thermoplastic resin component.
It is manufactured by an ordinary papermaking method using pulp fibers, a binder and the like. That is, the raw material liquid in which the binder is dissolved or dispersed in water is dehydrated on a wire (mesh) to form a wet paper, and then mechanical dehydration and heating are performed to dry the paper-like material. Is obtained.

Among them, the crushed product is mainly composed of inorganic fibers and thermoplastic resin, such as commercially available stampable sheets [trade names: Azdel (manufactured by Azdel), Ladrite (manufactured by Wiggins), etc.]. The crushed composite of is used. In addition, it is also possible to appropriately crush and use these recycled products, manufactured residue, and the like. The size after crushing is not particularly limited, but it is preferable to crush so that the inorganic fibers maintain a length of 1 to 5 mm.

The pulp fiber is a fiber usually used in paper and is not particularly limited.

PVA (polyvinyl alcohol), CMC (carboxymethyl cellulose), HEC (hydroxyethyl cellulose) and the like are preferably used as the binder.

When a paper-like material produced by mixing the same amount of thermoplastic resin fibers or powder as the thermoplastic resin film together with the above raw materials is used, it is necessary to laminate the thermoplastic resin film in the laminating step. It is possible to form a laminated body by laminating only paper-like materials.

In the heating step, the laminate is heated to a temperature above the melting temperature of the resin component to melt the resin component. At this time, any heating method may be adopted,
For example, a hot air heating method, a radiant heating method using an infrared heater, etc. may be mentioned. In the compression step, the laminate is compressed in the molten state. At this time, any method may be adopted, and examples thereof include a pressing method and a method of compressing with a roll. Pressing pressure is 0.1-20Kg
/ Cm ² and the compression time may be 1 to 10 seconds. Also, when compressing with rolls, the space between rolls is
It is preferably set to 0 to 5%.

When both the press and the roll are compressed, it is preferable that they are heated to a temperature above the melting temperature of the thermoplastic resin. When compressed at this time, the molten thermoplastic resin is impregnated into the inorganic fibers.

Next, when the pressure is released, the material tries to recover to the original thickness, but the inorganic fiber is once crushed and thus cannot be recovered sufficiently. Therefore, it is preferable to go through a spreading process such as performing vacuum suction from above and below. In the expansion step, the pressure applied in the compression step is released and the thermoplastic resin is melted,
Expands and increases material thickness.

To shape the fiber composite thus obtained, reheating to a temperature above the melting temperature of the resin component,
Compression molding such as pressing may be performed, and for use as an automobile ceiling material, for example, upon compression molding, a decorative skin material such as vinyl chloride leather, a nonwoven fabric, or a woven cloth may be laminated and shaped.

[0023]

According to the present invention as set forth in claim 1, in the laminating step, a pulverized product of a composite composed of an inorganic fiber and a thermoplastic resin component, a paper-like material composed of a pulp fiber and a binder is provided on the outer side of the thermoplastic resin film. Since they are laminated, the inorganic short fibers, pulp fibers, resin, and the like that compose these layers fill the needle punching holes, local depressions, and the like of the mat-like material.

According to the second aspect of the present invention, in the laminating step, a pulverized product of a composite of thermoplastic resin fibers or powder, inorganic fibers and a thermoplastic resin component is used without using a thermoplastic resin film. Since the paper-like material composed of the pulp fiber and the binder is laminated, the inorganic short fibers, the pulp fiber, the resin, and the like that compose the same fill the needle punching holes and the local depressions of the mat-like material.

[0025]

EXAMPLES Examples according to the present invention and comparative examples for comparison will be shown below to clarify the reason why the present invention is excellent.

As the pulp fiber in each example, a regenerated product of ordinary mechanical pulp (manufactured from crushed wood) and used for tissue paper, toilet paper and the like was used.

[0027]

Example 1 Glass fiber having a length of 50 mm and a diameter of 13 μm
And a polypropylene fiber with a length of 50 mm and a diameter of 10 μm
After feeding and to the card machine in a weight ratio of 3: 1 and weaving
1 cm²Needle punching at 60 points per thickness 6
mm, average weight 350 g / m ²To obtain a mat-like product.

Next, a thickness of 120 μm (115
A high density polyethylene film of MI5 was laminated at a rate of g / m ² ) and paper-like materials were further laminated on both sides to form a laminate. However, paper-like material is 100 g / m ^2, the mat-like material and ground product 50 g / m ² of a complex made of a thermoplastic resin in which the inorganic fibers mainly pulp fibers 45 g / m ^2,
The polyvinyl alcohol produced was 5 g / m ² .

Then, the whole was sandwiched between Teflon sheets, heated at 200 ° C. for 3 minutes, compressed at a pressure of 5 Kg / cm ² with a press heated to 200 ° C., and then at 200 ° C.
Keep the Teflon sheet vacuumed from both sides and keep it at 3.5.
After expanding to mm, it was cooled.

The bending strength of the obtained sample was measured according to JIS
It was measured according to K 7221.

The number of measurements was 30, and the average value of strength and the standard deviation of strength variation were calculated. The results are shown in Table 1.

[0032]

Example 2 A glass fiber having a length of 50 mm and a diameter of 13 μm and a 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 defibrated 1c.
6m thick with 60 needle punches per m ^2.
A mat-like material having an average weight of 350 g / m ² was obtained.

Next, a paper-like material was laminated on both sides to form a laminate. However, the paper-like material is 215 g / m ² , the crushed product of the composite consisting of the mat-like material mainly composed of inorganic fibers and the thermoplastic resin is 50 g / m ² , and the pulp fiber is 45 g / m ² .
^2. Polyvinyl alcohol was used in an amount of 5 g / m ² and polypropylene fiber was used in an amount of 115 g / m ² .

Next, the whole was sandwiched between Teflon sheets, heated at 200 ° C. for 3 minutes, compressed at a pressure of 5 Kg / cm ² by a press heated to 200 ° C., and then at 200 ° C.
Keep the Teflon sheet vacuumed from both sides and keep it at 3.5.
After expanding to mm, it was cooled.

The bending strength of the obtained sample was measured according to JIS
It was measured according to K 7221.

The number of measurements was 30, and the average value of strength and the standard deviation of strength variation were calculated. The results are shown in Table 1.

[0037]

Comparative Example 1 Example 1 except that no paper-like material was used.
A sample was prepared in the same manner as in. The bending strength was also measured in the same manner. The results are shown in Table 1.

[0038]

[Comparative Example 2] Two films to be laminated on both sides of the mat-like material
A sample was prepared in the same manner as in Example 1 except that the thickness was 26 μm (215 g / m ² ) and the paper-like material was not used (the weight was the same except for the paper-like material). The bending strength was also measured in the same manner. The results are shown in Table 1.

[0039]

Comparative Example 3 A sample was prepared in the same manner as in Example 1 except that the mat-like material was 550 g / m ² and the paper-like material was not used (the weight was the same except for the paper-like material). The bending strength was also measured in the same manner. The results are shown in Table 1.

[0040]

[Table 1]

[0041]

As described above, according to the present invention, since inorganic short fibers, pulp fibers, resin and the like fill the needle punching holes and local depressions of the mat-like material, the bending strength varies. Is reduced, and particularly weak areas are eliminated. As a result, it is possible to obtain a fiber composite having uniform strength with little variation in strength and also improving the average strength of the whole.

Claims (2)

[Claims] 1. A laminating step of laminating a film made of a thermoplastic resin on a non-woven mat-like material mainly made of inorganic fibers to form a laminated body, and heating the laminated body at a temperature not lower than a melting temperature of the resin component. And a heating step for melting the resin component, and a compression step for compressing the laminate in this molten state,
A method for producing a fiber composite, which comprises sequentially expanding the laminate to expand the thickness of the laminate in a molten state of the resin component, wherein the thermoplastic resin film is used in the laminating process. A method for producing a fiber composite, which comprises laminating a pulverized product of a composite composed of an inorganic fiber and a thermoplastic resin component, a paper-like material composed of a pulp fiber and a binder on the outside of. 2. A pulverized product of a composite of inorganic fibers and a thermoplastic resin component, a pulp fiber, a binder, and a thermoplastic resin film in the laminating step without using a thermoplastic resin film.
The method for producing a fiber composite according to claim 1, wherein a paper-like material made of thermoplastic resin fiber or powder is laminated.