JPH09248868A - Composite plastic panel and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture simply a composite panel of light-weight and superior mechanical strength without using a foamed material for an intermediate layer by molding integrally a layer containing micro-balloons selected out of a group of glass balloons and plastic balloons for the intermediate layer and a fiber reinforced layer for an upper layer and a lower layer. SOLUTION: While an impregnated mixture 19 for an upper layer is introduced over an impregnated mixture 16 for a lower layer, a compound 8 for an intermediate layer composed of a mixture of micro-balloons such as glass balloons and plastic balloons with thermosetting resin liquid for the intermediate layer is introduced between the impregnated mixture 19 for the upper layer and the impregnated mixture 16 for the lower layer, and the above-said three layers are laminated and integrated. Then a three-layer structure thus formed is impregnated by impregnation rollers 9, 9 and squeezed out by squeeze rollers 10, 10 to the given thickness of the intermediate layer, and then defoamed and passed through a heating oven 20 for thermosetting, and then an upper film 12 and a lower film 2 are peeled off to manufacture a composite plastic panel 21 of integrated three layers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight resin layer containing a microballoon such as a glass balloon or a plastic balloon as an intermediate layer, and a fiber-reinforced resin layer laminated on both sides of this resin layer and integrally molded. Composite plastic panel and its manufacturing method.

[0002]

2. Description of the Related Art A composite plastic panel in which both surface layers are fiber reinforced resin layers and a foam material is provided in an intermediate layer to reduce the weight is lightweight and has mechanical strength. It is widely used because it is suitable for upholstery materials, roofing materials, transportation equipment such as automobiles, railroads, ships, etc., outer layer board materials and land and sea container members. However, since the shape and size of the foam cells that constitute the foam material that is the intermediate layer are non-uniform, the resulting composite plastic panel is unstable in quality, and in particular, the compressive strength varies widely and is generally low. Is.

As a well-known technical method of this kind of composite plastic panel, a method in which a plate-shaped foam material is sandwiched between fiber-reinforced resin plates, an adhesive is applied and compression molding is performed, and a reinforcing fiber is used. There is a method in which a plate-shaped foam material is sandwiched between the prepregs, and compression molding is performed, but both of them require a step of forming a fiber reinforced resin plate or a brig leg in advance. Further, the prepreg of the reinforcing fiber needs to be carefully made so that the reinforcing fiber is sufficiently impregnated with resin and there are no bubbles. Otherwise, air bubbles will remain in the outer layer material of the finished composite plastic panel, and not only the appearance will be poor, but also mechanical properties such as strength will not be sufficient. Furthermore, in any case, since compression molding is required, pressing is required, and pressure distribution occurs on the pressed surface, resulting in insufficient adhesion at the interface between the middle layer and the upper and lower outer layer portions. , Quality tends to vary.

Therefore, for example, Japanese Patent Laid-Open No. 4-241936.
Then, two sheets of reinforcing fibers are provided, and a flat foam material is sandwiched between the two reinforcing fiber sheets, and then the flat foam material and / or the fibrous sheet is thermally expanded. Injecting particles and thermosetting resin liquid, heating and expanding the thermally expandable particles while pressing, the internal pressure due to thermal expansion causes the thermosetting resin to seep into the fibrous sheets of both outer layers, and the intermediate layer Discloses a method of manufacturing a composite plastic panel having a foam core. However, even in this case, a press is required, so even if continuous production is possible, the production speed is limited, and when producing a long composite plastic panel, a large-scale facility for press is required. Become. Further, there is no doubt that the use of a foam material causes the problem that the quality is unstable.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above problems and provides a lightweight, high mechanical strength composite plastic panel that does not use a foam material as an intermediate layer, and is simple and It aims to provide stable quality. Moreover, the present invention is intended to provide a method for continuously manufacturing an extremely long composite plastic panel.

[0006]

According to the present invention, a resin layer containing a microballoon selected from the group consisting of glass balloons and plastic balloons is integrally formed as an intermediate layer and a fiber reinforced resin layer as an upper layer and a lower layer. The present invention relates to a composite plastic panel having a layer structure. Since the intermediate layer is a resin layer containing a microballoon selected from the group consisting of glass balloons and plastic balloons, and both surface layers are fiber-reinforced resin, the intermediate layer is lightweight and both surface layers have high mechanical strength. The obtained composite plastic panel is lightweight and has excellent mechanical strength. In addition, since micro balloons such as glass balloons and plastic balloons are fairly uniform in size and shape, they are lightweight and excellent in quality.

Further, by providing a gel coat layer on the outer surface of at least one of the upper and lower layers of the fiber-reinforced resin layer of the composite plastic panel of the present invention, heat resistance is improved.
It is possible to obtain a composite plastic panel excellent in water resistance or aesthetic appearance.

The present invention also provides a three-layer composite plastic in which a resin layer containing a microballoon selected from the group consisting of glass balloons and plastic balloons is formed as an intermediate layer and a fiber reinforced resin layer is formed as an upper layer and a lower layer. When manufacturing a panel, (a) an uncured lower layer thermosetting resin liquid is applied onto a belt-shaped conveyor that moves at a constant speed, and a lower layer reinforcing fiber is applied onto the applied lower layer thermosetting resin liquid. Depositing and impregnating the lower layer reinforcing fiber for impregnating the lower layer thermosetting resin liquid to form a lower fiber reinforced resin layer; (b) a glass balloon and a glass balloon on the upper portion of the lower fiber reinforced resin layer; Forming an intermediate layer by applying a compound for an intermediate layer containing a microballoon selected from the group consisting of plastic balloons, (c) a thermosetting resin for an upper layer on the intermediate layer And then supplying the upper layer reinforcing fibers onto the uncured upper layer thermosetting resin liquid to form a fiber-reinforced resin layer by impregnating the liquid thermosetting resin into the upper layer reinforcing fibers. (D) A method for producing a composite plastic panel, comprising the steps of squeezing out the composite laminate including the upper layer, the intermediate layer, and the lower layer, and then curing and molding. As described above, since the intermediate layer includes the microballoons and the foam material is not used, it is not necessary to bond the intermediate layer and the upper and lower layers with the adhesive, and the thermal expansion of the intermediate layer by the heat-expandable particles is not required. So
A press may be unnecessary.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the method for manufacturing a composite plastic panel of the present invention, the step (a) and the step (b) are carried out.
It is preferable to provide a step of disposing a separation sheet between the step and the step of disposing a separation sheet between the step (b) and the step (c). The separating sheet is preferably a sheet selected from the group consisting of non-woven glass fabric, woven glass fabric and titanium paper. By providing the separating sheet, when the three layers are laminated and then the three layers are squeezed with a squeeze roller, the glass balloon and / or the resin layer containing the plastic balloon, which is the intermediate layer, is almost completely transferred to the glass balloon and the plastic balloon. However, almost only the resin passes through the separation sheet and is transferred by the upper and lower layers. Therefore, the intermediate layer is filled with microballoons such as glass balloons and plastic balloons at an extremely high density, and the upper and lower fiber-reinforced resin layers are impregnated with the resin that has exuded from the intermediate layer, resulting in a highly impregnable composite plastic panel. Is obtained.

In the composite plastic panel, a gel coat layer may be provided on the outer surface of at least one of the upper and lower layers made of the fiber reinforced resin layer.

The microballoon which is one component constituting the intermediate layer used in the present invention is a glass balloon or a plastic balloon having a hollow inside, and for example, glass balloon, vinylidene chloride balloon, shirasu balloon and the like can be used. In particular, glass balloons are non-expandable inorganic hollow particles and can be preferably used.
The microballoons may be solid particles such as calcium carbonate and iron powder, a liquid substance such as n-hexane and liquid paraffin, or those in which the solid particles are dispersed in the liquid substance inside the hollow.

The type of reinforcing fibers constituting the upper and lower fiber-reinforced resin layers may be inorganic fibers, organic fibers or metal fibers generally used as a reinforcing material for fiber-reinforced resin, such as glass fiber and carbon. Fiber, alumina fiber,
Carbite fiber is optional. In particular, glass fiber can be preferably used because it has excellent performance and is inexpensive. When glass fiber is used, the fiber diameter is 3 to 20 μm
Can be used. In addition to constituting the fiber-reinforced resin layer, the types of reinforcing fibers for the lower layer may be the same or different.

The kind of resin constituting the upper and lower fiber reinforced resin layers of the composite plastic panel is not particularly limited as long as it is a thermosetting resin usually used as a fiber reinforced plastic, and examples thereof include unsaturated polyester resin and epoxy resin. , Vinyl ester resin, urethane resin, phenol resin and the like can be used.

The content of reinforcing fibers in the upper and lower fiber reinforced resin layers is arbitrary, but is preferably 20 to 40% by weight. In this case, the content ratios of the reinforcing fibers in the upper layer and the lower layer may be the same or different.

The upper and lower fiber reinforced resin layers of the three-layer structure are not particularly limited in thickness, but the thickness is 0.5 to 3.0 mm, and the thickness of the intermediate layer is 1.0 to 10.0 mm. Is preferred.

In the composite plastic panel, a gel coat layer may be provided on the outer surface of at least one of the upper and lower layers made of a fiber reinforced resin layer. In that case, a known gel coat resin having the respective characteristics was used. The composition may be blended.

Next, one example of the method for producing the composite plastic panel of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic explanatory drawing of a process showing an example of a method for producing a composite plastic panel of the present invention. FIG. 2 is a schematic explanatory view showing an example of another manufacturing method in which a long fiber-shaped reinforcing fiber is cut into a certain length as the lower layer reinforcing fiber 1 and the separating sheets 7 and 15 are used.

In FIG. 1, first, while the thickness is regulated by a doctor knife 4 on a lower carrier film 2 drawn on a belt-shaped conveyor 17 which moves at a constant speed (constant speed),
After the thermosetting resin liquid 3 for the lower layer is applied, it is preheated by the preheating furnace 5 if necessary. The term “moving at a constant speed” in the invention of the present application means moving at an arbitrary predetermined speed, and includes moving while changing the speed from the middle. Then, a mat of reinforcing fibers is drawn out as the lower layer reinforcing fibers 1 and supplied onto the lower layer thermosetting resin liquid 3. The thermosetting resin liquid 3 for lower layer and the reinforcing fiber 1 for lower layer supplied to the upper portion are passed while being sandwiched between the impregnating rotary rollers 6 and 6, and the thermosetting resin liquid 3 for lower layer is supplied to the reinforcing fiber 1 for lower layer. To obtain a lower layer impregnation mixture 18.

On the other hand, as shown in the upper right portion of FIG. 1, a mat of reinforcing fibers as upper layer reinforcing fibers 11 is pulled out from a roll and supplied onto the upper carrier film 12. Further, the upper layer thermosetting resin liquid 13 is applied onto the upper layer reinforcing fibers 11 supplied onto the upper carrier film 12, and the thickness is regulated by a doctor knife 14. Then, the upper layer thermosetting resin liquid 13 is impregnated into the upper layer reinforcing fibers 11 through the space between the impregnating rotary rollers 16 to obtain an upper layer impregnating mixture 19.

Next, while guiding the upper layer impregnating mixture 19 onto the lower layer impregnating mixture 16, at the same time, a compound for an intermediate layer comprising a mixture of microballoons such as glass balloons and plastic balloons and a thermosetting resin liquid for an intermediate layer. 8 is introduced between the upper layer impregnation mixture 19 and the lower layer impregnation mixture 16, and these three layers are laminated and united. Next, the three-layer structure of the impregnation mixture 19 for the upper layer, the compound 8 for the intermediate layer, and the impregnation mixture 118 for the lower layer is impregnated with the impregnating rotary rollers 9 and 9, and the squeeze roller 1 is used.
Squeeze out at 0 and 10 to regulate the thickness of the intermediate layer to a desired value, and after defoaming, pass through the heating furnace 20 and
After heating and curing at 150 ° C. for 5 to 30 minutes, the upper carrier film 12 and the lower carrier film 2 are peeled off to obtain the composite plastic panel 21 of the present invention in which the three layers are integrated. If necessary, the composite plastic panel may be followed by a step of cutting the both ends to be ears.

The lower carrier film 2 and the upper carrier film 12 that can be used in the present invention are not particularly limited as long as they can be peeled off after curing and molding, but for example, polyethylene resin, polypropylene resin,
A film having a thickness of 25 to 125 μm made of nylon resin, saturated polyester resin, cellophane, or the like can be used.

The reinforcing fibers 1 constituting the upper and lower fiber-reinforced resin layers are not only in the form of a mat, but also of a woven fabric,
It may be a non-woven fabric, a knitted fabric, a braid or the like. Further, in the case of forming a mat of reinforcing fibers, a continuous fiber-like reinforcing fiber 1 is cut into a certain length by a known cutting device and is sprinkled and accumulated on the belt-shaped conveyor 17 to form a mat of reinforcing fibers. You can also

Preheating can be carried out by preheating the lower layer thermosetting resin liquid 3 by the preheating furnace 5 if necessary, so that the viscosity and impregnation characteristics of the thermosetting resin liquid 3 can be properly maintained. . By providing the preheating furnace 5, when the gel coat layer is provided on the outer surface of the lower layer composed of the fiber reinforced resin layer in the composite plastic panel, it can be used for curing the gel coat resin.

In the hardening and molding in the heating furnace, the temperature in the first half of the heating furnace may be lowered to slow the hardening, and the temperature in the latter half after the hardening may be set higher. The heating conditions are preferably 60 to 150 ° C. and 2 to 15 minutes. In the method for manufacturing a composite plastic panel of the present invention, as shown in FIG. 2, between the steps (a) and (b), the steps (b) and (c).
Separation sheets 7 and 15 may be arranged both during and after the step. These separation sheets 7, 15
By selecting the type of
It is possible to increase the ratio of the microballoons in the intermediate layer and to improve the surface condition of the upper and lower layers by controlling the amount of resin that migrates from the upper layer to the upper layer.

The separating sheet is made of various natural fibers, synthetic fibers,
Examples include metal fibers, inorganic fibers such as glass fibers, titanium fibers, ceramic fibers, and woven fabrics, knitted fabrics, braids, non-woven fabrics, papers, and the like made of aramid fibers, carbon fibers, and the like, and particularly woven fabrics of glass fibers. The non-woven fabric is inexpensive and easily available, and titanium paper is preferably used because it leads to an improvement in the appearance design of the obtained composite plastic panel 24 when the surface is subjected to design printing such as a pattern or a pattern. it can.

The size of the microballoon used is
V. S. A 80 mesh (177 μm) sieve having a residual rate of 5 wt% or less is preferable. V. S. When it is 100 mesh (149 μm) or more, the viscosity of the intermediate compound becomes high and it may be difficult to supply the intermediate compound. The mixing ratio of the mixture of the microballoons such as glass balloons and plastic balloons in the intermediate layer and the thermosetting resin liquid for the middle layer is 5:95 to 50:50 (weight by weight) so that the viscosity of the mixture becomes 15 to 150 poise. Ratio) is preferred.

In order to provide the gel coat layer on the composite plastic panel 21 of the present invention, the preheating furnace 5 of FIG. 2 is arranged after the application of the thermosetting resin liquid 3 for the lower layer, and the preheating furnace 5 is provided.
By heat-curing the gel coat resin layer, the gel coat layer can be provided on the outer surface under the composite plastic panel 21.

[0028]

【Example】

Example 1 Under the following conditions, the intermediate layer is a resin layer containing microballoons such as glass balloons and plastic balloons according to the method of FIG. 1, and has a three-layer structure in which an upper layer and a lower layer are fiber-reinforced resin layers. A molded composite plastic panel was obtained.

<Manufacturing conditions> a. Upper and lower carrier films: made of polyethylene resin, thickness 25 μm b. Composition of upper and lower thermosetting resin liquids: unsaturated polyester resin NA-128 100 parts manufactured by Dainippon Ink and Chemicals, Inc. (viscosity 3.0 poise) methyl ethyl ketone peroxide 1 part c. Preheating of thermosetting resin liquid for lower layer: 4 minutes, 40 ° C. d. Reinforcing fibers for upper and lower layers: glass chopped strand mat 1PLY manufactured by Nitto Boseki Co., Ltd. (MC450N) e. Compound composition for intermediate layer: Microballoon: Glass balloon (completely hollow) 20 parts Sumitomo 3M Co., Ltd., K-1 (50 μm, true specific gravity 0.09) Unsaturated polyester resin 80 parts Dainippon Ink and Chemicals ( Co., Ltd. intermediate layer compound viscosity: 50 poise f. Separation sheet: None g. Heating conditions: 90 to 115 ° C., 15 minutes h. Line speed: 3m / min

The obtained composite plastic panel was as follows. Upper layer glass fiber content rate: 27% by weight, thickness 1 mm Middle layer glass balloon content rate: 30% by weight, thickness 1 mm Lower layer glass fiber content rate: 27% by weight, thickness 1 mm

Example 2 Under the following conditions, a three-layer structure in which the intermediate layer is a resin layer containing microballoons such as glass balloons and plastic balloons and the upper layer and the lower layer are fiber-reinforced resin layers is prepared by the method of FIG. An integrally molded composite plastic panel was obtained. <Manufacturing conditions> a. Upper and lower carrier films: made of polyethylene resin, thickness 25 μm b. Upper and lower thermosetting resin liquid compounding composition: unsaturated polyester resin PS-2210 100 parts manufactured by Hitachi Chemical Co., Ltd. (viscosity 4.5 poise) methyl ethyl ketone peroxide 1 part c. Preheating of thermosetting resin liquid for lower layer: 4 minutes, 35 ° C d. Reinforcing fibers for upper and lower layers: Glass strands were pulled out from upper glass roving (RS240H555 manufactured by Nitto Boseki Co., Ltd.) and cut into 50 mm. Lower layer glass chopped strand mat Nitto Boseki Co., Ltd. (MC450N) e. Compound for middle layer Composition: Micro balloon: Glass balloon (completely hollow) 16 parts Sumitomo 3M Co., K-1 (50 μm, true specific gravity 0.09) Unsaturated polyester resin 84 parts Dainippon Ink and Chemicals, Inc. NA -128 Viscosity of compound for intermediate layer: 18 poise f. Separation sheet: glass cloth (WF-230C manufactured by Nitto Boseki Co., Ltd.) g. Heating condition: 90 to 115 ° C, 15 minutes h. Line speed: 3 m / minute

The resulting composite plastic panel was as follows: Upper layer glass fiber content rate: 30% by weight, thickness 1 mm Middle layer glass balloon content rate: 30% by weight, thickness 3 mm Lower layer glass fiber content rate: 30% by weight, thickness 1 mm

[0033]

INDUSTRIAL APPLICABILITY The composite plastic panel of the present invention is excellent in soundproofing and sound insulation because the middle layer portion is made of a resin layer containing microballoons, and it is possible to obtain one having no variation in quality such as mechanical strength. To be Further, since the method for producing a composite plastic panel of the present invention does not use a pressing device, continuous production is extremely easy, and an extremely long composite plastic panel, which was considered impossible in the past, can be produced. it can.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an example of a method for manufacturing a composite plastic panel of the present invention.

FIG. 2 is a schematic explanatory view showing another example of the method for manufacturing the composite plastic panel of the present invention.

[Explanation of symbols] 1 Reinforcing fiber for lower layer 2 Lower carrier film 3 Thermosetting resin liquid for lower layer 4 Doctor knife for lower layer 5 Preheating furnace 6 Rotating roller for impregnation 7 Upper separating sheet 8 Compound for intermediate layer 9 Rotating roller for impregnation 10 Squeeze Roller 11 Reinforcing Fibers for Upper Layer 12 Upper Carrier Film 13 Thermosetting Resin Liquid for Upper Layer 14 Doctor Knife for Upper Layer 15 Lower Separation Sheet 16 Rotary Roller for Impregnation 17 Belt Conveyor 18 Lower Layer Mixture 19 Upper Layer Mixture 20 Heating Furnace 21 Composite Plastic Panel 22 Cutter 23 Reinforcing fiber roving

Claims (7)

[Claims] 1. A composite plastic panel having a three-layer structure in which a resin layer containing a microballoon selected from the group consisting of glass balloons and plastic balloons is integrally molded as an intermediate layer and a fiber reinforced resin layer as an upper layer and a lower layer. 2. The composite plastic panel according to claim 1, further comprising a separating sheet between the upper layer and the intermediate layer of the fiber reinforced resin layer and between the intermediate layer and the lower layer. 3. The composite plastic panel according to claim 2, wherein the separation sheet is a sheet selected from the group consisting of glass nonwoven fabric, glass woven fabric, and titanium paper. 4. The composite plastic panel according to claim 1, further comprising a gel coat layer on an outer surface of at least one of an upper layer and a lower layer made of the fiber reinforced resin layer. 5. A composite plastic panel having a three-layer structure in which a resin layer containing microballoons selected from the group consisting of glass balloons and plastic balloons is integrally formed with an intermediate layer, a fiber reinforced resin layer as an upper layer and a lower layer as a lower layer. In doing so, (a) an uncured lower layer thermosetting resin liquid is applied on a belt-shaped conveyor that moves at a constant speed, and a lower layer reinforcing fiber is deposited on the applied lower layer thermosetting resin liquid. A step of impregnating the lower layer reinforcing fiber with the lower layer thermosetting resin liquid to form a lower fiber reinforced resin layer, (b) a glass balloon and a plastic balloon on the upper portion of the lower fiber reinforced resin layer. Applying a compound for an intermediate layer containing a microballoon selected from the group consisting of: to form an intermediate layer, (c) supplying a thermosetting resin liquid for an upper layer onto the intermediate layer, and A step of supplying the upper layer reinforcing fiber onto the uncured upper layer thermosetting resin liquid and impregnating the liquid thermosetting resin into the upper layer reinforcing fiber to form a fiber reinforced resin layer; A method for producing a composite plastic panel, which comprises the steps of squeezing out a composite laminate including an upper layer, an intermediate layer, and a lower layer, and then curing and molding. 6. A step of placing a separation sheet is provided between the step (a) and the step (b) and between the step (b) and the step (c). The method for manufacturing the composite plastic panel according to claim 5. 7. The method for producing a composite plastic panel according to claim 6, wherein the separation sheet is a sheet selected from the group consisting of a glass nonwoven fabric, a glass woven fabric, and titanium paper.