WO2000006375A1

WO2000006375A1 - Laminated liner

Info

Publication number: WO2000006375A1
Application number: PCT/KR1999/000394
Authority: WO
Inventors: Byung Chan Keum
Original assignee: Byung Chan Keum
Priority date: 1998-07-31
Filing date: 1999-07-22
Publication date: 2000-02-10
Also published as: AU4935499A

Abstract

The disclosure is a laminated liner including: a fiber reinforced composite non-woven fabric prepared by mixing 20-60 % by weight of a mixture of a chemical short fibers having a higher melting point and a reinforcing long fiber, with 40-80 % by weight of chemical short fibers having a lower melting point; and a polyurethane foam having both sides or either side thereof being coated with the fiber reinforced composite non-woven fabric by means of an adhesive layer. The chemical short fibers having the higher melting point in the fiber reinforced composite non-woven fabric are any one selected from the group consisting of polyester short fibers, nylon short fibers, polyacrylonitrile short fibers, polyurea short fibers, polyurethane short fibers and a mixture of them. The chemical short fibers having the lower melting point in the fiber reinforced composite non-woven fabric are polypropylene short fibers or polyester short fibers having a low melting point. The reinforcing long fibers are natural long fibers, preferably, yam fibers.

Description

LAMINATED LINER

Technical Field

The present invention relates to a laminated liner usable to cover the inside of a motorcar and the like and, more particularly, to a light-weighted laminated liner with good formability and soundproofing property.

Background Art

Generally, soundproofing and heat-resistant laminates are chiefly used for lining and decorating the inside of a confined space such as motorcar, small-sized vessel including a yacht, or container house. The prior art laminated liners are, as shown in FIG. 1, composed of a fundamental layer 2 which is formed from a heavy-weighted, heat-resistant and soundproofing material such as a glass fiber plate, resin felt or paper board. The laminated liners further include a vinyl layer 6 formed from a polyethylene film and a finishing layer 8 formed from raw fabrics, non-woven fabrics or polyvinyl chloride sheet. Here, the vinyl layer 6 and the finishing layer 8 are adhered to the fundamental layer 2 with an adhesive layer 4.

However, the prior art laminated liners have the fundamental layer 2 constituted by a heavy-weighted material and the glass fiber itself is a heavy-weighted inorganic matter. Using the resin felt, which is prepared by immersing a thermosetting resin such as phenol resin in an ordinary felt, increases the weight of the liners themselves. Therefore, in a case where the prior art laminated liners having the fundamental layer 2 formed from those materials are applied to a motorcar, the motorcar adversely has the weight increased, with a consequence of a decrease in the fuel efficiency.

The prior art laminated liners also use a glass fiber or a paper board for the fundamental layer 2 so that they must be thick enough to attain excellent soundproofing and heat-resistant properties. For that reason, the thickened laminated liners can hardly contribute to the beautiful appearance .

Furthermore, the glass fiber causes the user to suffer from pneumonoconiosis and produces a large quantity of contaminants such as dusts to result in air pollution in the entire cycle of circulation including its preparation, handling and disposal. The resin felt also causes air pollution with poisonous gases given off in plenty during its incineration. With all of these problems, the prior art laminated liner is further disadvantageous in that it has poor soundproofing and heat-resistant properties and results in a high unit cost.

The present inventor therefore contrived the present invention in order to solve the above problems with the prior art laminated liner.

Disclosure of Invention

Accordingly, it is an object of the present invention to provide a laminated liner having good mechanical properties that is prepared to have good formability under heat and pressure by applying a fiber reinforced composite non-woven fabric inclusive of reinforcing long fibers such as natural fibers, on both sides of a polyurethane foam.

It is another object of the present invention to provide a very light-weighted laminated liner in which a fiber reinforced composite non-woven fabric inclusive of chemical short fibers and reinforcing long fibers is applied on a polyurethane foam.

It is further another object of the present invention to provide a laminated liner with enhanced formability using a fiber reinforced composite non-woven fabric obtained by mixing a mixture of chemical short fibers having a higher melting point and reinforcing long fibers with chemical short fibers having a lower melting point , as a result of which the laminated liner can be formed simply as the fiber reinforced composite non-woven fabric are heated and pressurized.

It is still further another object of the present invention to provide a laminated liner that can be produced at a reduced unit cost in a automatic and continuous production system.

It is still further another object of the present invention to provide a laminated liner made up of an excellent soundproofing and sound-shielding material and, especially, applicable to a liner for motorcar that will provide the driver with comfortable space in the car.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, there is provided a laminated liner including: a fiber reinforced composite non-woven fabric prepared by mixing 20-60% by weight of a mixture of a chemical short fibers having a higher melting point and a reinforcing long fiber, with 40-80% by weight of chemical short fibers having a lower melting point; and a polyurethane foam having both sides or either side thereof being coated with the fiber reinforced composite non-woven fabric by means of an adhesive layer. The chemical short fibers having the higher melting point in the fiber reinforced composite non-woven fabric are any one selected from the group consisting of polyester short fibers, nylon short fibers, polyacrylonitrue short fibers, polyurea short fibers, polyurethane short fibers and a mixture of them. The chemical short fibers having the lower melting point in the fiber reinforced composite non- woven fabric are polypropylene short fibers or polyester short fibers having a low melting point.

The reinforcing long fibers are natural long fibers, preferably, yam fibers.

Brief Description of Drawings

The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:

FIG. 1 is a schematic cross-sectional view of the prior art laminated liner;

FIG. 2 is a schematic cross-sectional view of a laminated liner according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of a laminated liner according to another embodiment of the present invention;

FIG. 4 is a diagram illustrating an example of a method for preparing a laminated liner in accordance with the present invention; and

FIG. 5 is a diagram illustrating another example of a method for preparing a laminated liner in accordance with the present invention.

Best Mode for carrying Out the Invention

Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings .

Referring to FIG. 2, there is shown an illustrative diagram of a laminated liner according to the present invention that is primarily used to finish and decorate the inside of a confined space such as motorcar, small-sized vessel including a yacht, or container house. The laminated liner has a laminated structure including a fiber reinforced composite non-woven fabric 14 adhered to both sides of a polyurethane foam 10 with an adhesive layer 12. As shown in FIG. 3, the laminated liner further include a finishing layer 8 adhered to the one side thereof with the adhesive layer 12. Examples of the finishing layer 8 used herein may be formed from the same materials as constituting the finishing layer of the prior art laminated liner, such as raw fabrics, glass fiber plate, non-woven fabric or polyvinyl chloride sheet.

The polyurethane foam 10 constitutes a fundamental layer together with the fiber reinforced composite non- woven fabric in place of the fundamental layers conventionally used for the prior art laminated liner, such as glass fiber, resin felt or paper board. The polyurethane foam 10 can be prepared by foaming polyurethane during its polymerization to provide a number of continuous or discontinuous pores therein.

The polyurethane foam 10 may be a thermoplastic polyurethane foam that is softened or melt with heat and becomes plastic, or a thermosetting polyurethane foam that is hardened with heat during the polymerization but cannot be plastic again with heat once it is hardened.

The fiber reinforced composite non-woven fabric 14 is adhered to both sides of the polyurethane foam 10 as newly contrived by the present inventor. The fiber reinforced composite non-woven fabric 14 is prepared by mixing a mixture of chemical short fibers having a higher melting point and reinforcing long fibers with chemical short fibers having the lower melting point, and used to facilitate molding materials into the laminated liner. Especially, as the chemical short fibers having the lower melting point are melted and compressed with heat and pressure during the molding step, the fiber reinforced composite non-woven fabric becomes adhesive of itself to fixedly combine the chemical short fibers having the higher melting point with the reinforcing long fibers. The polyurethane foam 10 is then adhered to the one side of the melted, fiber reinforced composite non-woven fabric with an adhesive layer that includes a hot melt film, a hot melt powder, a coating adhesive or an ordinary adhesive according to its use purpose and handling. In addition, the fiber reinforced composite non-woven fabric 14 is used to make the non-melt chemical short fibers having the higher melting point and the reinforcing long fibers be laminated densely to strengthen the mechanical properties of the laminated liner. This prevents the laminated liner having deformation, fracture or rupture under an external stress. The reinforcing long fibers used herein can be natural or synthetic long fibers, preferably, natural long fibers e.g., yam fibers or synthetic long fibers e.g., nylon that have excellent mechanical properties, especially, stress resistance. It should be understood that the reinforcing long fibers are used to strengthen the shock resistance of the fiber reinforced composite non-woven fabric and have the same or equivalent reinforcing function as or to that of the fibers in an ordinary FRP (Fiber Reinforced Plastic) .

It is preferable that 20-60% by weight of the mixture of the chemical short fibers having the higher melting point and the reinforcing long fibers is admixed with 40-

80% by weight of the chemical short fibers having the lower melting point.

Preferably, 0-40% by weight of the chemical short fibers having the higher melting point are admixed with 60- 100% by weight of the reinforcing long fibers.

Both the chemical short fibers having the higher melting point and the reinforcing long fibers are fiber components substantially constituting the non-woven fabric portion in the fiber reinforced composite non-woven fabric

14. The fractional ratio of the reinforcing long fibers can be increased so as to strengthen the stress resistance of the fiber reinforced composite unwoven fiber 14. This is considered because the reinforcing long fibers can substantially replace the chemical short fibers having the higher melting point and have the same or equivalent function as or to the chemical short fibers having the higher melting point.

In particular, the fiber reinforced composite non- woven fabric 14 strengthens the mechanical properties on the surface of the laminated liner lest that stretching be made on the surface of the laminated liner.

Among the components of the fiber reinforced composite non-woven fabric 14, the chemical short fibers having the higher melting point are selected from the group consisting of polyester short fibers, nylon short fibers, polyacrylonitrue short fibers, polyurea short fibers, polyurethane short fibers and a mixture of them. The term "having the higher melting point" generally refers to being melted at a temperature above 220°C. The polyester short fibers having a higher melting point are adequately used for the chemical short fibers having the higher melting point in the present invention since they have a melting point of about 240-260°C. Preferably, the chemical short fibers having the higher melting point are polyester short fibers having a higher melting point.

On the other hand, among the components of the fiber reinforced composite non-woven fabric 14, the chemical short fibers having the lower melting point are selected from the group consisting of polypropylene short fibers or polyester short fibers having a lower melting point. The term "having the lower melting point" generally refers to being melted at a temperature below 200°C. The polyester short fibers having a low melting point are adequately used for the chemical short fibers having the lower melting point in the present invention since they have a melting point of about 110-200°C.

The polyurethane foam 10, especially, thermoplastic and thermosetting polyurethane foam 10 is commercially available from international or domestic leading suppliers and can be understood by those skilled in the art.

The adhesive layer 12 used herein is prepared by melting an adhesive having a lower melting point such as hot melt film or hot melt powder, which are all a kind of adhesive commercially available easily melted and solidified, as understood by those skilled in the art. As illustrated in FIG. 3, the finishing layer 8 can be varied according to different use purposes. It is understood by those skilled in the art that the finishing layer 8 is applicable to hood lining, dash panel, carpet or trunk mat for motorcar. To promote the soundproofing effect, the finishing layer 8 may be an EVA (Ethylene-vinyl acetate resin) or PVC(Poly vinyl chloride resin) sheet applied to the polyurethane foam 10.

In a case where the adhesive layer 12 is formed from an adhesive film such as a hot melt film, as shown in FIG. 4, the polyurethane foam 10 is supplied to a transfer conveyer 30 in an intermittent or continuous manner. To form the adhesive layer 12 and the fiber reinforced composite non-woven fabric 14 on the upper and lower surfaces of the polyurethane foam 10, there are used adhesive film feeding roll 32 for supplying the adhesive film and non-woven fabric feeding roll 34 for supplying the fiber reinforced composite non-woven fabric 14. At the same time, the polyurethane foam 10 covered with the adhesive film and the fiber reinforced composite non-woven fabric 14 is guided to a hot pressurizing chamber 38 by means of guide rollers 36 and subjected to heating and pressurization into an integrally formed laminated liner. Out of the components constituting the fiber reinforced composite non-woven fabric 14, the chemical short fibers having the lower melting point are partially melted and filled in the spaces between the chemical short fibers having the higher melting point, to densely combine the chemical short fibers having the higher melting point together. As a result, the fiber reinforced composite non- woven fabric 14 thus melt and combined of itself is adhered to the surface of the polyurethane foam 10 with the adhesive layer 12. Thereafter, the laminated liner heated and pressurized is cooled by a cooling chamber 40 adjacent to the hot pressurizing chamber 38 so that the adhesive layer 12 and the chemical short fibers having the lower melting point out of the fiber reinforced composite non- woven fabric 14 are cooled and solidified adhesively. In the meanwhile, the fiber reinforced composite non-woven fabric 14 may have its thickness reduced by about 60-90%, with the surface thereof being hardened and adhered to the surface of the polyurethane foam 10. The entire of this process is performed simultaneously on both sides of the polyurethane foam 10 so that only one step of heating and pressurization is performed to form the laminated liner with both sides of the polyurethane foam 10 covered with the adhesive layer 12 and the fiber reinforced composite non-woven fabric 14. And also, to promote the hardness of the obtained laminated liner, it is preferable that the fiber reinforced composite non-woven fabric 14 is pressurized, then do such as the same processes so that the polyurethane foam 10 covered with the adhesive layer 12 and the fiber reinforced composite non-woven fabric 14. The laminated liner thus obtained is proceed to an ordinary post processing step in which it is cut to an appropriate size with a cutter 42 and, if necessary, printed or packaged.

In a case where the adhesive layer 12 is formed from an adhesive powder such as a hot melt powder, as shown in FIG. 5, the polyurethane foam 10 is supplied to the transfer conveyer 30 in an intermittent or continuous manner. An adhesive powder is applied to the upper surface of the polyurethane foam 10 by means of a dispenser 44 and then heated by a heater 46. The fiber reinforced composite non-woven fabric 14 is applied to the upper surface of the melt powder through the non-woven fabric feeding roll 34 and guided to the hot pressurizing chamber 38 by means of the guide rollers 36. Through the hot pressurizing chamber 38, the fiber reinforced composite non-woven fabric 14 covered on the polyurethane foam 10 is heated and pressurized into a laminated liner whose one side is finished with the fiber reinforced composite non-woven fabric 14. To finish both sides of the polyurethane foam 10 with the fiber reinforced composite non-woven fabric 14, the laminated liner whose one side is finished is reversed to the above procedure from the step of applying the adhesive powder to the step of heating and pressurizing through the hot pressurizing chamber 38. Now, reference will be made as to a description of Examples of the present invention. The following examples describe the preferred embodiments of the present invention and should not be interpreted as limiting the scope of the invention defined in the accompanying claims. [Example 1]

A fiber reinforced composite non-woven fabric is prepared by needle punching a mixture comprising 10% by weight of polyester short fibers having a higher melting point as chemical short fibers having a higher melting point, 30% by weight of yam fibers as natural reinforcing long fibers, and 60% by weight of polyester short fibers having a lower melting point as chemical short fibers having a lower melting point. The fiber reinforced composite non-woven fabric thus obtained and a hot melt powder layer is continuously applied to the upper surface of a polyurethane foam, heated to about 180 °C and pressurized to prepare a laminated liner. [Example 2]

A laminated liner is prepared by the same procedure as described in Example 1, except that the mixture comprises 40% by weight of yam fibers as the natural reinforcing long fibers and 60% by weight of polyester short fibers having a lower melting point as the chemical short fibers having a lower melting point.

The laminated liners thus obtained are examined for their physical properties such as heat resistance and weight in order to determine whether they are satisfactory as a laminated liner for motor cars.

Although there are slight differences in the test criteria and range according to the manufacturers of the motorcar, the test for the heat resistance is carried out in such a manner that variations of the product's shape are measured at a temperature ranging from 90 °C to 100 °C for about 3 hours .

As the laminated liners are subjected to severe conditions in the order of 90 °C (24 hours) → 40 °C (48 hours)→ 90 °C (24 hours) , they are examined in regard to bubbles, creases, decoloration and separation of adhesive layer on their surface. As a result of the heat resistance test, the laminated liners prepared in Examples 1 and 2 are found to have no bubble, creases, decoloration or separation of adhesive layer.

In addition, the laminated liners obtained in Examples 1 and 2 are found to have a weight of about 600-800 g/m², which value of the weight is slightly varied according to the density of the polyurethane foam used. The laminated liners of the present invention are found to be light- weighted compared to the prior art laminated liners made of a resin felt whose weight is about 900-1,700 g/m².

Industrial Applicability

Accordingly, the present invention provides a laminated liner including the fiber reinforced composite non-woven fabric 14, reinforced with the reinforcing long fibers, and the polyurethane foam, with enhanced mechanical properties, especially, shock resistance . Furthermore, the laminated liner of the present invention provided with good formability can be produced in an automatic and continuous production system at a reduced production cost.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as recited in the accompanying claims.

Claims

What is claimed is:

1. A laminated liner having a multi-layered structure, comprising: a fiber reinforced composite non-woven fabric prepared by mixing 20-60% by weight of a mixture of a chemical short fibers having a higher melting point and a reinforcing long fiber, with 40-80% by weight of chemical short fibers having a lower melting point; and a polyurethane foam having both sides or either side thereof being coated with the fiber reinforced composite non-woven fabric by means of an adhesive layer.

2. The laminated liner as claimed in claim 1, wherein the chemical short fibers having the higher melting point in the fiber reinforced composite non-woven fabric are any one selected from the group consisting of polyester short fibers, nylon short fibers, polyacrylonitrue short fibers, polyurea short fibers, polyurethane short fibers and a mixture of them.

3. The laminated liner as claimed in claim 1, wherein the chemical short fibers having the lower melting point in the fiber reinforced composite non-woven fabric are polypropylene short fibers or polyester short fibers having a low melting point.

4. The laminated liner as claimed in claim 1, wherein the reinforcing long fibers are natural long fibers.

5. The laminated liner as claimed in claim 4, wherein the natural long fibers are yam fibers.

6. The laminated liner as claimed in claim 1, wherein the laminated liner comprises: a fiber reinforced composite non-woven fabric prepared by mixing 20-60% by weight of a mixture of chemical short fibers and reinforcing long fibers, with 40-80% by weight of chemical short fibers having a lower melting point; and a polyurethane foam having one side thereof being covered with the fiber reinforced composite non-woven fabric by means of an adhesive layer, and the other side thereof being covered with a finishing layer.