JP2003062919A - Laminated sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated sheet having excellent adhesive properties with a surface material which is sufficiently present on a nonwoven fabric in a molten state of a synthetic resin layer for performing an adhesive action. SOLUTION: The laminated sheet A comprises the nonwoven fabric 2 made by binding entangled fibers to each other by a thermoplastic resin and integrally laminated on one surface of a thermoplastic resin foamed sheet 1, and a synthetic resin layer 3 integrally laminated on a surface of the fabric 2. In this case, the layer 31 has inner and outer resin layers 31 and 32 made of a thermoplastic resin in which the layer 31 is disposed at the fabric 2 side, the layer 31 is made of a resin having a melting point of 140 deg.C to 180 deg.C, and the layer 32 is made of a thermoplastic resin having a melting point of 60 deg.C to 140 deg.C. Further, a melt index of the resin for constituting the layer 32 is larger than that of the resin for constituting the layer 31.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminated sheet excellent in adhesiveness to a surface material.

[0002]

2. Description of the Related Art Conventionally, a surface material is laminated and integrated on the surface of a synthetic resin layer in a laminated sheet in which a nonwoven fabric and a synthetic resin layer are laminated and integrated on one surface of a foamed sheet with the nonwoven fabric inside and formed into a desired shape at the same time. It is used for automobile interior materials and the like (Japanese Patent Laid-Open No. 2001-3885).
No. 9).

Specifically, after heating the laminated sheet to a temperature at which the synthetic resin layer is melted, the surface material is laminated on the surface of the molten synthetic resin layer and then supplied into a male and female mold, By closing the male and female dies, the surface material is integrally laminated on one surface of the laminated sheet by the adhesive action of the synthetic resin layer, and the desired shape of the laminated sheet, for example, an automobile interior material is formed at the same time.

However, since a non-woven fabric is laminated and integrated on one surface of the foamed sheet in the above laminated sheet in order to improve dimensional stability and mechanical strength, it is a synthetic material that exhibits an adhesive action in a molten state. The problem that the resin layer penetrates into the above-mentioned non-woven fabric, there is not enough synthetic resin that exerts an adhesive action between the surface material and the non-woven fabric, and the adhesiveness between the surface material and the non-woven fabric deteriorates. was there.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a laminated sheet having a synthetic resin layer exhibiting an adhesive action sufficiently present on a nonwoven fabric in a molten state and having excellent adhesiveness to a surface material.

[0006]

In the laminated sheet according to the first aspect of the present invention, a non-woven fabric in which entangled fibers are bound by a thermoplastic resin is laminated and integrated on one surface of a thermoplastic resin foam sheet. Along with this, a laminated sheet in which a synthetic resin layer is laminated and integrated on the non-woven fabric surface, wherein the synthetic resin layer comprises an inner and outer resin layer, the inner resin layer is the non-woven fabric side, and the inner resin layer has a melting point. The outer resin layer is made of a thermoplastic resin having a temperature of 140 ° C. or higher and 180 ° C. or lower, and the outer resin layer is made of a thermoplastic resin having a melting point of 60 ° C. or higher and lower than 140 ° C. Is characterized by being larger than the melt index of the thermoplastic resin constituting the inner resin layer.

The laminated sheet according to claim 2 is the laminated sheet according to claim 1, wherein the thermoplastic resin forming the inner resin layer binds the resin forming the nonwoven fabric. It is characterized by having compatibility with.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An example of the laminated sheet of the present invention will be described with reference to the drawings. In the laminated sheet A, a nonwoven fabric 2 formed by binding entangled fibers to each other with a thermoplastic resin is laminated and integrated on one surface of a thermoplastic resin foam sheet 1, and a synthetic resin layer 3 is formed on the nonwoven fabric 2 surface. It is made by laminating and integrating.

As the thermoplastic resin foam sheet 1,
It is not particularly limited as long as it can be molded, for example, low density polyethylene, linear low density polyethylene, medium density polyethylene, polyethylene such as high density polyethylene, isotactic polypropylene, polypropylene such as syndiotactic polypropylene, and the like. Polybutene, ethylene
Polyolefin resin such as α-olefin copolymer; ethylene-propylene-diene terpolymer; ethylene-
Vinyl acetate copolymers; ethylene-acrylic acid ester copolymers; polystyrene, polystyrene-based resins such as polystyrene-based thermoplastic resin elastomers, and the like, and the resulting laminated sheet is lightweight, chemical resistant, flexible, and highly elastic. Polyolefin resin is preferable because it is excellent in
Polyethylene or polypropylene is more preferable, and a mixture of polyethylene and polypropylene is particularly preferable.
The α-olefin is propylene, 1-
Butene, 1-pentene, 1-hexene, 4-methyl-1
-Pentene, 1-heptene, 1-octene, and the like, and the copolymer containing an ethylene component may be a block copolymer, a random copolymer, or a random block copolymer. .

Further, the nonwoven fabric 2 laminated and integrated on one surface of the thermoplastic resin foam sheet 1 is formed by binding the entangled fibers with each other by the thermoplastic resin. The fibers forming the nonwoven fabric 2 are fibers that are not melted by the heat applied when the laminated sheet A is formed into a desired shape, in other words, regardless of the heat applied when the laminated sheet is formed into the desired shape. It is not particularly limited as long as it is a fiber that retains, for example, cotton, kapok surface, flax, cannabis, hemp (kenaf), Manila hemp, sisal hemp, New Zealand hemp, maga hemp, natural fiber such as koya, polyethylene terephthalate, etc. Synthetic resin fibers, glass fibers, carbon fibers, and the like.

Further, the above-mentioned fibers are entangled, and the fibers are partially or wholly bound by a thermoplastic resin. This thermoplastic resin has been conventionally used as a binder for nonwoven fabrics. The resin is not particularly limited, and examples thereof include polyethylene such as low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, and high-density polyethylene, polypropylene such as isotactic polypropylene, syndiotactic polypropylene, and polybutene. Polyolefin resins such as ethylene-α-olefin copolymers; ethylene-propylene-diene terpolymers; ethylene-vinyl acetate copolymers; ethylene-acrylic acid ester copolymers; polystyrene,
Polystyrene resin such as polystyrene thermoplastic resin elastomer; polyvinyl alcohol resin; saturated polyester resin; unsaturated polyester resin; polymethyl (meth) acrylate, polybutyl (meth) acrylate, poly-n-tetradecyl (meth) acrylate, Acrylic resins such as poly-n-propyl (meth) acrylate and polyisobutyl (meth) acrylate; urethane resins such as linear urethane resins; epoxy resins; dimethyl phthalate; phthalic acid derivatives such as dimethyl isophthalate; vinyl acetate resins And the like, and a polyolefin-based resin is preferable from the viewpoint of the heat fusion property with the thermoplastic resin foam sheet.

As the above α-olefin, propylene, 1-butene, 1-pentene, 1-hexene, 4-
Methyl-1-pentene, 1-heptene, 1-octene and the like can be mentioned, and the copolymer containing an ethylene component is either a block copolymer, a random copolymer or a random block copolymer. May be.

Further, a synthetic resin layer 3 is laminated and integrated on the non-woven fabric 2, and the synthetic resin layer 3 comprises inner and outer resin layers 31, 32. The inner resin layer 31, that is, the resin layer 31 laminated and integrated on the nonwoven fabric 2 has a melting point of 140 ° C.
Made of a thermoplastic resin having a temperature above 180 ° C.,
Among them, those having compatibility with the thermoplastic resin binding the entangled fibers forming the nonwoven fabric 2 are preferable.

As such a thermoplastic resin, polyolefin resins such as polypropylene such as isotactic polypropylene and homopolypropylene are preferable.

When the melting point of the thermoplastic resin is high, the temperature at which the inner resin layer 31 is laminated and integrated on the nonwoven fabric 2 is increased, and the thermoplastic resin foam sheet 1 is easily deformed by heat. If it is low, the inner resin layer is formed on the nonwoven fabric 2.
When the 31 is laminated and integrated, the thermoplastic resin forming the inner resin layer permeates into the nonwoven fabric 2, and the thermoplastic resin forming the outer resin layer that exerts an adhesive action is formed on the laminated sheet A.
Since it does not sufficiently exist on the surface, it is limited to 140 ° C or higher and 180 ° C or lower, and 140 ° C or higher and 170 ° C
The following are preferred.

The outer resin layer 32 laminated and integrated on the inner resin layer 31 has a melting point of 60.degree.
It is composed of a thermoplastic resin having a temperature of less than ° C. Such a thermoplastic resin forming the outer resin layer 32 may be compatible with the thermoplastic resin forming the inner resin layer 31, low density polyethylene, linear low density polyethylene, medium Polyolefin resins such as polyethylene such as high density polyethylene and high density polyethylene and polypropylene such as syndiotactic polypropylene are preferable.

When the melting point of the thermoplastic resin forming the outer resin layer 32 is high, the surface material is laminated and integrated on the nonwoven fabric 2 of the laminated sheet A via the synthetic resin layer, and at the same time, the laminated sheet A is formed into a desired shape. When molding is attempted, the outer resin layer 32 may not melt and the adhesive force may not be expressed. If it is low, a nonwoven fabric is obtained when the molded product obtained by molding the laminated sheet A is left at a high temperature. Since the surface material laminated on and integrated with the synthetic resin layer 3 on the surface 2 is peeled off from the nonwoven fabric 2 by re-melting the outer resin layer 32, the surface material is limited to 60 ° C. or higher and lower than 140 ° C. It is preferably not lower than 0 ° C and not higher than 120 ° C.

The inner and outer resin layers 31, 32 are formed so that the melt index of the thermoplastic resin forming the outer resin layer 32 is larger than the melt index of the thermoplastic resin forming the inner resin layer 31. The thermoplastic resin to be used is selected.

The reason for this will be described below. When the laminated sheet A is used, the surface material is laminated and integrated on one surface (front surface) thereof. At this time, the outer resin layer 32 is melted and the surface material is laminated and integrated on one surface of the laminated sheet A. Acts as an adhesive. Therefore, the outer resin layer 32 must be surely present on one surface of the laminated sheet A, and at the same time, must have excellent fluidity when melted.

On the other hand, since a large number of voids formed between fibers are formed on the surface of the nonwoven fabric 2, the molten synthetic resin enters the nonwoven fabric 2 through the voids, is absorbed by the nonwoven fabric 2 and disappears. There is a risk of doing it.

Therefore, in the laminated sheet A, the nonwoven fabric 2
The thermoplastic resin forming the inner resin layer 31 directly laminated on top has a melting point of 140 ° C. or higher and 180 ° C. or lower and a small melt index to provide appropriate fluidity at the time of melting, and a nonwoven fabric. Inner resin layer in 2
Allow a portion of the thermoplastic resin that constitutes 31 to enter appropriately,
The inner resin layer 31 is configured so as to maintain the state in which the inner resin layer 31 is reliably laminated and integrated on the nonwoven fabric 2.

A melting point of 6 is provided on the inner resin layer 31 which is surely present in a layered manner on the non-woven fabric 2, in other words, on the inner resin layer 31 which has a function of sealing the voids on the surface of the non-woven fabric 2.
An outer resin layer 32 made of a thermoplastic resin having a large melt index and a large fluidity at the time of melting at 0 ° C. or higher and lower than 140 ° C.
It is possible to exhibit excellent fluidity while surely presenting 32 on one surface of the laminated sheet A without being absorbed by the nonwoven fabric 2 when it is melted, and thus it is possible to form the outer resin layer 32 with excellent fluidity. The thermoplastic resin is allowed to smoothly and surely enter the irregularities or voids of the surface material, and the surface material is applied to the outer resin layer.
By 32, the laminated sheet A can be surely laminated and integrated on one surface.

Here, specifically, the above-mentioned outer synthetic resin layer
If the melt index of the thermoplastic resin forming 32 is high, the thermoplastic resin in the molten state easily flows in the surface direction of the outer resin layer 32, and the thickness of the outer resin layer 32 in the surface direction becomes uneven. Therefore, the adhesiveness between the non-woven fabric 2 and the surface material may become non-uniform, and when the adhesiveness is low, the fluidity in the molten state decreases, and the adhesiveness between the non-woven fabric 2 and the surface material decreases. Therefore, 5 to 30 g / 10 minutes is preferable, and 7 to 20 g / 10 minutes is more preferable. The melt index of the above-mentioned thermoplastic resin is JIS
The value measured in accordance with K7210.

If the thermoplastic resin constituting the inner resin layer 31 has a high melt index, it will penetrate into the nonwoven fabric 2 when melted, and the adhesiveness between the surface material and the nonwoven fabric 2 will deteriorate. In some cases, if it is too low, the amount of invasion into the non-woven fabric 2 may be reduced and the adhesiveness between the non-woven fabric 2 and the inner resin layer 31 may be reduced.
Minute is preferable, and 1 to 10 g / 10 minutes is preferable. In addition,
The melt index of the thermoplastic resin is JIS K
It is measured according to 7210.

Although the case where the nonwoven fabric 2 is laminated and integrated only on one surface of the thermoplastic resin foam sheet 1 has been described above, the case where the nonwoven fabrics 2 and 2 are laminated and integrated on both surfaces of the foam sheet 1 has been described. Good.

The method for producing the laminated sheet is not particularly limited, and for example, fibers are entangled with each other on one side of the expandable sheet which is a raw material of the thermoplastic resin foam sheet, and the fibers are thermoplastic. A thermoplastic resin foam sheet obtained by laminating a nonwoven fabric formed by binding with a resin to form a foamable laminated sheet, foaming the foamable sheet of the foamable laminated sheet, and foaming the foamable sheet. An inner and outer resin layer is laminated on the non-woven fabric by laminating and integrating the non-woven fabric and further thermally laminating a laminated film comprising a resin film constituting the inner resin layer and a resin film constituting the outer resin layer on the non-woven fabric. Method for manufacturing laminated sheet by integrating, thermoplastic resin foamed sheet is heated on one side and then nonwoven fabric is laminated on the one side of the foamed sheet to form laminated foam Of the thermoplastic resin foam sheet and the nonwoven fabric by pressing the laminated foam sheet from both sides to form a resin film and an outer resin layer forming an inner resin layer on the nonwoven fabric of the laminated foam sheet. A method of producing a laminated sheet by thermally laminating a laminated film composed of a resin film constituting the above and the like can be mentioned.

The laminated sheet A is formed into a desired shape after the surface material is laminated and integrated on the outer resin layer 32 side, and is used, for example, as an automobile interior material.
Specifically, the outer layer 32 is heated by heating the laminated sheet A.
Is melted and a surface material is laminated on the outer resin layer 32 and then supplied into a male and female mold, and by closing the male and female molds, the surface material is attached to one surface of the laminated sheet A by the adhesive action of the outer resin layer 32. Simultaneously with the lamination and integration, the laminated sheet A is formed into a desired shape, for example, the shape of an automobile interior material.

At this time, the synthetic resin layer 3 of the laminated sheet A
Is composed of inner and outer resin layers 31, 32, and these inner and outer resin layers 31, 32
In, while the resin layer having a relatively high melting point and a low melt index is the inner resin layer 31, while the resin having a relatively low melting point and a relatively high melt index is the outer resin layer 32, At the time of forming the laminated sheet A, the fluidity of the inner resin layer 31 is moderated, and a part of the inner resin layer 31 is appropriately penetrated into the nonwoven fabric 2 so that the adhesiveness between the inner resin layer 31 and the nonwoven fabric 2 is improved. The inner resin layer 31 serves to seal the voids on the surface of the non-woven fabric 2 while at the same time ensuring that the non-woven fabric 2 does not allow the non-woven fabric 2 to absorb the outer fluid layer 32 having high fluidity. Therefore, the surface material can be reliably laminated and integrated on one surface of the laminated sheet A by the synthetic resin layer 3, and at the same time, the laminated sheet A can be surely molded into a desired shape.

[0029]

Example 1 A polypropylene foam sheet (trade name “Softlon SP” manufactured by Sekisui Chemical Co., Ltd., foaming ratio: 14.6 cc / g, thickness: 6 mm) was heated on both sides to form a molten state. Then, the fibers of the core-sheath structure in which the polyethylene terephthalate component is coated with the polyethylene component are entangled on both surfaces of the polypropylene-based foamed sheet 1, and these fibers are bonded together by heat-sealing polyethylene of the sheath portion. Non-woven fabric 2 made by wearing (product name "Elves" manufactured by Unitika Ltd., basis weight: 50)
g / m ² ) is laminated to produce a laminated foam sheet, and the laminated foam sheet is pressed from both sides to laminate and integrate the non-woven fabric 2 on both sides of the polypropylene foam sheet 1. A polypropylene resin film (melting point = 160 ° C., melt index = 8 g / 10 minutes, thickness: 15 μm) that constitutes the inner resin layer 31 and a metallocene-based polyethylene that constitutes the outer resin layer 32 on one of the nonwoven fabrics 2 Inner / outer resin layers 31, 32 are laminated on the nonwoven fabric 2 by thermally laminating a laminated film made of a resin film (melting point = 110 ° C., melt index = 10 g / 10 min, thickness: 45 μm) with a polypropylene resin film inside. Integrated to produce a laminated sheet A.

Example 2 Example 1 was repeated except that a polypropylene resin film (melting point = 128 ° C., melt index = 15 g / 10 minutes, thickness: 45 μm) was used as the resin film forming the outer resin layer 32. A laminated sheet A was manufactured in the same manner as in.

Comparative Example 1 Instead of the resin film forming the inner and outer resin layers 31, 32, a polypropylene resin film (melting point = 166.7 ° C., melt index = 4 g /
A laminated sheet A was produced in the same manner as in Example 1 except that only 10 minutes, thickness: 100 μm) was extrusion-laminated on the nonwoven fabric.

(Comparative Example 2) As a resin film forming the inner resin layer 31, a polyethylene resin film (melting point =
At 112 ° C., melt index = 10 g / 10 minutes, thickness: 15 μm, a polypropylene resin film (melting point = 12) was used as a resin film forming the outer resin layer 32.
8 ° C., melt index = 15 g / 10 minutes, thickness: 4
A laminated sheet A was produced in the same manner as in Example 1 except that 5 μm) was used.

The adhesiveness of the laminated sheet A obtained as described above was measured by the method shown below, and the results are shown in Table 1.

(High temperature adhesiveness) Outer resin layer of laminated sheet A
A non-woven fabric formed by interlacing polyethylene terephthalate fibers as a surface material is laminated on 32 to form a first laminated sheet, and the first laminated sheet is heated to a surface temperature of 175 ° C. The laminated sheet was pressed from both sides for 25 seconds to obtain a plate-shaped molded product in which the surface material was laminated and integrated on one surface of the laminated sheet. The average surface temperature of the first laminated sheet was 148 ° C while the first laminated sheet was being pressed.

Then, from the above-mentioned molded product, width 25 mm × length 1
Cut a 50 mm flat vertical rectangular test piece and pull the surface material of the molded product along the surface of the molded product until it reaches the center of the test piece from the end of the test piece in the lengthwise direction. At that time, Peel strength was measured.

(Low Temperature Adhesion) The average surface temperature of the first laminated sheet is 120 while the first laminated sheet is pressed.
A molded product was obtained in the same manner as the low-temperature adhesiveness except that the temperature was set to 0 ° C, and the peel strength was measured in the same manner as the low-temperature adhesiveness.

[0037]

[Table 1]

[0038]

INDUSTRIAL APPLICABILITY In the laminated sheet of the present invention, a nonwoven fabric formed by binding entangled fibers to each other with a thermoplastic resin is laminated and integrated on one surface of a thermoplastic resin foamed sheet, and the nonwoven fabric surface is synthesized. A laminated sheet in which resin layers are laminated and integrated, wherein the synthetic resin layer comprises inner and outer resin layers, the inner resin layer is on the non-woven fabric side, and the inner resin layer has a melting point of 140 ° C. or higher and 180 ° C. The outer resin layer has a melting point of 60 ° C.
Made of a thermoplastic resin having a temperature above 140 ° C.,
Further, the melt index of the thermoplastic resin forming the outer resin layer is larger than the melt index of the thermoplastic resin forming the inner resin layer. In the inner and outer resin layers, the melting point of the inner resin layer is 140 ° C. or higher. And 1
By forming it from a thermoplastic resin having a melt index of 80 ° C. or less and a relatively low melt index, a part of the thermoplastic resin forming the inner resin layer can be appropriately introduced into the gap of the nonwoven fabric to surely integrate with the nonwoven fabric. The outer resin layer made of thermoplastic resin having a relatively low melting point and a high melt index is laminated and integrated on the inner resin layer which is surely present on the non-woven fabric and securely laminated and integrated on the non-woven fabric. I am letting you.

Therefore, since the thermoplastic resin forming the outer resin layer is laminated and integrated on the nonwoven fabric via the inner resin layer, it does not enter and disappear in the nonwoven fabric, and the outer resin layer does not disappear. It surely exists on the inner resin layer, exhibits excellent fluidity when melted, and reliably adheres the surface material to one surface of the laminated sheet.

Moreover, the thermoplastic resin forming the inner resin layer has a melting point of 140 ° C. or higher and 180 ° C. or lower, and the thermoplastic resin forming the outer resin layer has a melting point of 60 ° C. or higher and 140 ° C. or higher. Since the temperature is lower than 0 ° C, the laminated sheet exhibits excellent flexibility at the time of molding, has excellent moldability, and can be easily and surely molded into a desired shape.

In the laminated sheet, if the thermoplastic resin forming the inner resin layer is compatible with the thermoplastic resin binding the fibers of the non-woven fabric to the inner resin layer, The non-woven fabric can be more surely laminated and integrated, and therefore the unexpected situation that the inner resin layer and the non-woven fabric are separated from each other at the interface during molding or the like does not occur.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a laminated sheet of the present invention.

[Explanation of symbols]

1 foam sheet 2 non-woven fabric 3 synthetic resin layer 31 Inner resin layer 32 Outer resin layer A laminated sheet

Claims (2)

[Claims] 1. A non-woven fabric formed by binding entangled fibers to each other with a thermoplastic resin is laminated and integrated on one surface of a thermoplastic resin foam sheet, and a synthetic resin layer is laminated and integrated on the non-woven fabric surface. A laminated sheet consisting of
The synthetic resin layer is composed of inner and outer resin layers, the inner resin layer is on the side of the nonwoven fabric, the inner resin layer is made of a thermoplastic resin having a melting point of 140 ° C. or higher and 180 ° C. or lower, and the outer resin layer is melted. Is 60 ° C. or higher and lower than 140 ° C., and the melt index of the thermoplastic resin forming the outer resin layer is larger than the melt index of the thermoplastic resin forming the inner resin layer. Characteristic laminated sheet. 2. The thermoplastic resin forming the inner resin layer,
The laminated sheet according to claim 1, which is compatible with the thermoplastic resin that binds the fibers of the non-woven fabric.