JP2721820B2 - Fiber reinforced thermoplastic resin laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber-reinforced thermoplastic resin laminate reinforced with a fiber reinforcing material, which can be thermoformed, and is used for a core material for an automobile interior, a seat shell, a bumper beam and the like. The present invention relates to a fiber-reinforced thermoplastic resin laminate.

[0002]

2. Description of the Related Art Conventionally, various thermoplastic resin moldings reinforced with a fiber reinforcing material have been known. For example, a resin molded article in which a thermoplastic resin is reinforced with inorganic fibers such as glass fibers and carbon fibers or organic fibers such as aramid fibers as a reinforcing material is known.

[0003] Further, in these resin molded articles, those using long fibers as a reinforcing material are known for the purpose of further increasing the physical strength. As such a molded body,
For example, a so-called stampable sheet obtained by using a resin sheet and a nonwoven fabric-like reinforcing material made of long fibers as a molding material, and laminating them under pressure, is shaped by a mold after heating. However, although a molded article made of a stampable sheet can be thermoformed, the physical strength of the obtained resin molded article is not always sufficient. That is, the rigidity of the resin molded body is improved to some extent by increasing the content of the nonwoven fabric reinforcing material, but even in that case, the tensile strength is not improved. Furthermore, the molded article made of the stampable sheet has a problem that the surface is poor in smoothness and the fibers float on the surface of the molded article and the appearance quality is not improved. Furthermore, thermoforming using a stampable sheet has the disadvantage that relatively high pressure press forming such as stamping is required for the purpose of impregnating the fibers with the resin.

[0004] Further, as a molding material of a molded article, there is a method in which a composite of a resin sheet and a woven cloth-like reinforcing material made of continuous fibers is used, and the composite is heated and shaped by a mold. However, in the molding material made of such a composite, although the improvement of the physical strength of the resin molding is expected,
Because the degree of freedom of deformation of the reinforcing material is small, wrinkles occur in the molding material at the time of molding, and breakage, etc., it can not be molded by conventional thermoforming known conventionally, for example, male and female molds in press molding The molding material is restrained by the projections and the engagement portions provided on the joint surface (Japanese Patent Laid-Open No. 5-2697).
52) Alternatively, a fiber restraining pin of a frame portion for clamping the material is pierced into the molding material, and the material is restrained according to the deformation of the molding material (Japanese Patent Laid-Open Nos. 4-176630 and 4-176630).
At present, special means such as -176631) must be adopted.

[0005]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above-mentioned prior art, and can be applied to a conventional thermoforming method, and has a rigidity, a tensile strength and an endurance. It is an object of the present invention to provide a fiber-reinforced thermoplastic resin laminate capable of obtaining a resin molded body having high physical strength such as impact strength and excellent appearance quality.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention uses at least one kind of woven fabric-like fiber reinforcing material, and uses the reinforcing material when laminating the same with a thermoplastic resin sheet. Focusing on the positional and quantitative relationship between the resin and the resin, if this is set within a certain range of conditions, normal thermoforming is possible, and physical properties such as rigidity, tensile strength and impact resistance It has been found that a resin molded body having high strength and excellent appearance quality can be obtained.

That is, according to the present invention, at least one layer of a woven fabric-like fiber reinforcing material is provided at a vertically symmetric position of a resin substrate.
A laminate in which the outermost resin surface layers are respectively superposed and integrated by heating and pressing, wherein the content of the fiber reinforcing material is set to 10 to 40% by volume of the entire laminate, and The gist is a fiber-reinforced thermoplastic resin laminate characterized in that the thickness is set to 1.5 to 10 mm.

[0008] The invention of claim 2 is characterized in that at least one or more layers of non-woven fabric reinforcing material are further laminated inside the woven fabric reinforcing material.

Further, the invention according to claim 3 is characterized in that the thickness of the outermost resin surface layer is set to 0.1 to 1.0 mm.

Further, the invention according to claim 4 is characterized in that the ratio occupied by the resin substrate is set to 10 to 80% by volume of the whole laminate.

As the reinforcing fiber reinforcing material used in the present invention, inorganic fibers such as glass fiber and carbon fiber or organic fibers such as aramid fiber are applied as the material.
As for the form, at least one kind of a woven cloth and a nonwoven cloth are selectively used.

Here, as the woven fabric-like fiber reinforcing material, for example, glass cloth such as plain weave, satin weave, twill weave or the like woven from yarn made of glass fiber, or roving woven from roving made of glass fiber Cloths and even knits are applied. Further, as the non-woven fabric fiber reinforcing material, for example, short fiber mats such as chopped strand mats made of glass fiber, surfacing mats, or long fiber mats such as diamond mats and swirl mats are applied. Applied.

The fiber diameter of the fiber reinforcing material is 3 to 24.
ones μm is also basis weight weight, in the case of glass fibers, those woven fabric-like is 20~1000g / m ^2, those non-woven fabric of those 300~1000g / m ² is preferably used.

Next, in the present invention, the thermoplastic resin used together with the fiber reinforcing material will be described. The thermoplastic resin is used for a substrate, an adhesive layer between the fiber reinforcing materials, and a surface layer because of the structure as a laminate. Respectively.

The kind of the thermoplastic resin used here is such that the melting temperature is 3 in order to form a thermoformable laminate.
Those having a temperature of 00 ° C. or lower are preferably used, and for example, polycarbonate, polymethyl methacrylate, ABS, rigid polyvinyl chloride, polypropylene and the like are preferably applied.
It is not limited to these. Here, the reason for using a thermoplastic resin having a melting temperature of 300 ° C. or lower is that the heating temperature in the thermoforming method applied to the formation of the laminate of the present invention is the same as the heating temperature of a far-infrared heater or the like usually used for the same. The reason is that the temperature is relatively low due to the ability, for example, the heater temperature is about 450 ° C., and the high melting point resin is generally difficult to thermoform and the molding cycle becomes long.

The form of these thermoplastic resins is mainly in the form of a sheet or a film, but it is a part of a so-called prepreg which is impregnated with a fiber reinforcing material in advance from a powder or liquid state. May be replaced by the configuration of Furthermore, for the substrate, for the adhesive layer and for the surface layer, it is not limited to the same type of thermoplastic resin, as long as there is no problem such as delamination on the lamination, even if different types of thermoplastic resins are applied. Good. Among these, for the substrate, a foamed thermoplastic resin may be applied for the purpose of reducing the weight of the laminate, imparting heat insulating properties, sound absorbing properties, and the like, in addition to solid ones. Here, the foamable thermoplastic resin refers to one that has already foamed before lamination and one that is not foamed before lamination but foams during lamination.

Next, the lamination structure of the fiber-reinforced thermoplastic resin laminate of the present invention will be described. Basically, the laminated structure consists of a resin substrate at the center, a fiber reinforcement via a resin adhesive layer at a vertically symmetrical position on the resin substrate, and a resin surface layer on the outermost layer. The structure is integrated with heating. The first reason for adopting such a laminated structure is that when a laminate is thermoformed, a resin substrate is provided in the center, a resin surface layer is provided on the outermost side, and further, a bonding between fiber reinforcing materials is performed. By interposing the resin layer, the displacement between the fiber reinforcing material itself and the fiber reinforcing material due to deformation of the laminate during thermoforming can be easily performed by the softened resin substrate, the surface resin layer, and the adhesive resin layer. This is because, when the thermoforming is completed, the intended deformation is fixed by cooling and solidifying the resin substrate and each resin layer. The second reason is to provide the resin surface layer to prevent the fiber reinforcement from floating on the surface of the fiber and to obtain the smoothness of the surface of the molded body.

The fiber reinforcing material can be laminated by modifying the lamination structure as follows. That is, one example of lamination is a case where the fiber reinforcement is constituted by one kind of woven cloth-like fiber reinforcement. In another configuration example, at least one kind of woven fabric-like material and at least one non-woven fabric-like material are used as fiber reinforcing materials.
This is the case when more than one species are used together. It goes without saying that a resin adhesive layer is interposed between two or more adjacent fiber reinforcing materials. The resin adhesive layer enhances the laminability between adjacent reinforcing materials on the upper and lower sides of the resin substrate. Still another configuration example is a case where a fiber reinforced material is the prepreg. In this case, the impregnating resin constituting a part of the prepreg can be replaced with a part of the resin substrate, a resin adhesive layer and a resin surface layer.

Next, the quantitative relationships among the fiber reinforcing material, the resin substrate, the resin surface layer, and the resin adhesive layer constituting the laminate according to the present invention will be described below.

First, the thickness of the laminate in the present invention is:
The range is 1.5 to 10 mm. If the thickness is less than 1.5 mm, the absolute amount of the thermoplastic resin is reduced, plastic deformation during thermoforming is insufficient, and the necessary displacement of the fiber reinforcing material is less likely to occur. Not only does the cut off, or the corners of the formed body become defective in shape, the desired formed body cannot be obtained, but also the smoothness of the surface of the thin laminated body of less than 1.5 mm is ensured. Has the problem of requiring high pressure during thermoforming,
Further, even if the smoothness of the surface can be ensured, the rigidity and impact resistance that can withstand practical use cannot be obtained because of the thin plate shape. Also, if it exceeds 10 mm, during thermoforming, the temperature distribution in the thickness direction during heating tends to be uneven,
It is difficult to obtain molded products with good appearance quality. In addition, the heating time increases and the molding cost increases. Therefore, the thickness of the laminate should be in the range of 1.5 to 10 mm, preferably in the range of 2.0 to 8.0 mm.

Next, the content of the fiber reinforcing material in the laminate will be described. The fiber reinforcing material is 10 to 40% by volume of the total volume of the fiber reinforced thermoplastic resin laminate. If it is less than 10% by volume, the total amount of the thermoplastic resin of the resin substrate, the resin adhesive layer and the resin surface layer, which is relatively plastically deformed, becomes excessive and the modulus of elasticity of the entire laminate decreases, and sufficient rigidity cannot be obtained. , No reinforcing effect is exhibited. On the other hand, if it exceeds 40% by volume, the amount of the thermoplastic resin which undergoes plastic deformation relatively becomes insufficient, and the necessary displacement during the thermoforming of the fiber reinforcing material, especially the woven fabric fiber reinforcing material, is less likely to occur. Excessive force is applied to the material, causing fiber breakage, or a corner portion of the molded article having a poor shape, and a desired molded article cannot be obtained. Therefore, the content of the fiber reinforcement is 10 to 4
It is defined as 0% by volume, and is preferably set to 12 to 36% by volume.

Further, the ratio occupied by the resin substrate is 10 to 80 times the total volume of the fiber-reinforced thermoplastic resin laminate.
% By volume. If it is less than 10% by volume, the resulting laminate has a reduced impact resistance, lacks a relatively plastically deformable resin component, and is required to be misaligned at the time of thermoforming of a fiber reinforcing material, especially a woven fabric fiber reinforcing material. Is less likely to occur, and the thermoformability decreases. On the other hand, if it exceeds 80% by volume, the rigidity is reduced, and the molded product is not practical. Preferably 15 to 4
0% by volume. In addition, as described above, this resin substrate
For the purpose of reducing the weight of the laminate and the like, a foamable thermoplastic resin can be appropriately used. In this case, the expansion ratio of the resin substrate is not particularly limited, but is preferably in the range of 2 to 10 times in consideration of impact resistance and wall thickness reduction due to pressure during molding.

The thickness of the resin surface layer in the laminate is defined by the thickness, and the thickness is 0.1 to 1 mm. If the thickness is less than 0.1 mm, the desired smoothness of the surface of the molded article cannot be obtained, and if it exceeds 1 mm, the smoothness has no more remarkable effect, but rather lowers the rigidity of the molded article. Preferably 0.2 to
0.5 mm.

Further, the resin adhesive layer is provided between the reinforcing members adjacent to each other so as to enhance the laminating property, and the relative displacement between the fiber reinforcing members can be easily controlled. Although not particularly limited, it is usually 0.
A 1 mm film resin is commonly used. However, it is not preferable to make the molded body excessively thick because the rigidity of the molded body is reduced. Generally, it may be in the range of 0.08 to 0.12 mm.

In the fiber-reinforced thermoplastic resin laminate of the present invention, a resin substrate, a fiber reinforcing material, a resin adhesive layer and a resin surface layer are placed in the above-mentioned order, and this is heated and pressurized by a known method such as a hot platen. , A heating roll, an autoclave and the like to integrate by heating. As a thermoforming method applied when the laminated body after lamination and integration is molded into a desired molded body, a so-called match molding method of a press molding method or a molding method similar thereto is preferable.

[0026]

1 and 2 illustrate a laminated structure of a fiber reinforced thermoplastic resin laminate according to an embodiment of the present invention.

First, in FIG. 1, a laminate (1) comprises two layers of woven fiber reinforcements (3) and (3) at the symmetrical positions on both the upper and lower sides of a resin substrate (2). ), And further, the resin surface layers (5) and (5) are stacked on the outside thereof, and then heated and pressed by a hot press to be integrated.

In FIG. 2, the laminate (11) has two layers of nonwoven fabric reinforcing materials (13) and (13) and woven fabrics on the outside thereof at symmetrical positions on both the upper and lower sides of the resin substrate (2). The fiber reinforcing materials (3) and (3) are stacked via resin adhesive layers (4) and (4), and furthermore, resin surface layers (5) and (5)
And then created in the same manner as above.

[0029]

【Example】

Examples 1 to 7 Each element of the fiber reinforcing material, the resin substrate, the resin surface layer, and the resin adhesive layer was varied in its type, content in the laminate, and the like as shown in Table 1. 230 ° C., pressure 5 kgf / cm ² , heating time 1 by the hot press
Various fiber-reinforced thermoplastic resin laminates were prepared under the condition of 0 minutes. The configuration of the laminate shown in FIGS. 1 and 2 corresponds to the first and fourth embodiments, respectively.

The fiber reinforcing materials used here are as follows. Fiber reinforcement A: Glass fiber woven fabric Weight per unit area: 208 g
/ M ² (Nippon Sheet Glass Co., Ltd. YEM2103-T1 epoxy silane treated product) Fiber reinforcement B: non-woven fabric made of glass fiber Weight 380
g / m ² (RC380T manufactured by Unitika Glass Fiber Co., Ltd.)
115 epoxy silane treated product)

The thermoplastic resin used for the substrate, the surface layer, and the adhesive layer is a commercially available polycarbonate resin film (specific gravity: 1.2) and has a thickness of 0.1.
The thickness and the number were appropriately selected and determined from those having a thickness of about 0.5 mm so as to match the thickness of each resin layer in Table 1.

In order to confirm the effects of the present invention, the various laminates obtained above were formed into a container-like molded body having a length of 150 mm, a width of 200 mm, a depth of 50 mm and a bottom corner R of 10 mm by match molding. did. The molding conditions were as follows: the heating temperature (surface temperature) of the laminate was 250 ° C., the mold moving speed for pressing was 20 mm / sec, the molding pressure (surface pressure) was 40 kgf / cm ² , and the pressure holding time was The test was performed at 120 sec.

Comparative Examples 1 to 6 The same fiber reinforcing material, resin substrate, resin surface layer, and resin adhesive layer as used in Examples 1 to 7 Various kinds of laminates were prepared by subjecting the contents in the body to various changes and hot pressing under the same conditions as described above.

With respect to the various laminates thus obtained,
In order to compare with the effects of the present invention, molding of a molded body was attempted by match molding in the same manner as in Examples 1 to 7.

[0035]

[Table 1] The laminates obtained in Examples 1 to 7 and Comparative Examples 1 to 6 were measured for flexural modulus and impact strength, and were compared and evaluated. The results are also shown in Table 1. In addition, each said measurement was performed as follows.

[Flexural Modulus] The flexural modulus was measured in accordance with ASTM D790. In the present invention, the evaluation standard of the flexural modulus was 50,000 Kg / cm ² or more.

[Impact strength] The measurement conditions were as follows:
A weight with a hammer R of 1/8 inch is dropped on the surface of each laminated body sample fixed horizontally and around the periphery. If there is no abnormality at a drop distance of 50 cm or more, ◎, there is a slight dent, but there is no problem in practical use The sample was rated as ×, and the sample that was broken or cracked and failed was rated as ×.

Further, the molding state when each of the laminates was thermoformed by match mold molding was observed, and the appearance of the molded body was observed by visual inspection. The results are also shown in Table 1. The evaluation was as follows.

[Possibility of Molding] A molded article was not broken by thermoforming, and a cross was broken.

[Appearance] Regarding the finished state of the molded article such as smoothness of the molded article surface, presence or absence of wrinkles, presence or absence of fibers, and state of the bottom corner of the molded article, ◎ indicates that the surface is inconspicuous.が あ る indicates that there was unevenness or protrusion of the fiber but did not hinder practical use, and × indicates that there was some abnormality. × ¹⁾ … Glass fiber jumped out on the outer surface of the bottom corner of the molded product. × ²⁾ : Wrinkles occurred at the rising portion of the molded body.

As shown in Table 1, the laminates obtained by properly setting the positional and quantitative conditions of the fiber reinforcing material and the thermoplastic resin as in Examples 1 to 7 were all rigid. And excellent impact resistance. On the other hand, Comparative Examples 1 and 4 were inferior in rigidity, and Comparative Examples 3 and 6 were inferior in impact resistance. Further, in Examples 1 to 7, all of the laminates were excellent in thermoformability, and the obtained molded articles had good finish and excellent appearance quality. On the other hand, Comparative Examples 2 and 3
In this case, the volume percentage of the fiber reinforcing material is excessive, or the thickness of the laminate is too thin, so that thermoforming is difficult. In Comparative Example 6, the appearance quality was poor due to wrinkles.

[0042]

As described above, according to the present invention, at least one symmetrical portion of the resin substrate is provided between the upper and lower symmetric positions via the resin adhesive layer.
By laminating the resin surface layer on the outermost layer with more than one layer of woven fabric-like fiber reinforcement, the fiber reinforcement itself and the gap between each other when integrated by heating and pressing can be easily performed. In addition, the appropriate fiber reinforcement material content and the appropriate thickness of the resin substrate, resin adhesive layer and resin surface layer were set, so that excellent rigidity and impact resistance were maintained, and ordinary heat A laminate that can be formed can be obtained. Furthermore, the laminated body according to the present invention can obtain a molded article having a good appearance quality, in which the molded article obtained by thermoforming the molded article has a smooth surface and does not cause the fibers of the fiber reinforcement to jump out or break. This has the effect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a fiber-reinforced thermoplastic resin laminate according to an embodiment of the present invention, illustrating an example of a laminate configuration of the laminate.

FIG. 2 is a cross-sectional view of a fiber-reinforced thermoplastic resin laminate according to another embodiment of the present invention, showing another example of the laminate configuration.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 11 ... Laminated body 2 ... Resin board 3 ... Woven fabric-like fiber reinforcement 4 ... Resin adhesive layer 5 ... Resin surface layer 13 ... Non-woven fabric-like fiber reinforcement

Claims (4)

(57) [Claims] 1. A laminated body in which at least one or more layers of a woven fiber reinforcement and an outermost resin surface layer are respectively superposed and vertically integrated with each other at vertically symmetric positions of a resin substrate. Wherein the content of the fiber reinforcing material is set to 10 to 40% by volume of the entire laminate and the thickness of the laminate is set to 1.5 to 10 mm. Resin laminate. 2. The fiber-reinforced thermoplastic resin laminate according to claim 1, wherein at least one layer of a non-woven fiber reinforcement is laminated inside the woven fiber reinforcement. 3. The thickness of the outermost resin surface layer is from 0.1 to
3. The fiber-reinforced thermoplastic resin laminate according to claim 1, wherein the thickness is set to 1.0 mm. 4. The resin substrate occupies 1% of the entire laminate.
The fiber reinforced thermoplastic resin laminate according to any one of claims 1 to 3, which is set to 0 to 80% by volume.