JPS60181136A - Production of prepreg - Google Patents

Abstract

PURPOSE:To prevent the restoration of reinforcing fiber to its original shape, and produce a prepreg having smooth surface, by laminating a resin-supporting sheet to reinforcing fibers, heating and pressing the laminate with an impregnation roll, and cooling the laminate without delay, thereby immediately raising the viscosity of the resin. CONSTITUTION:The reinforcing fibers 1 are supplied from the package 2 parallely in a sheet form. The lower resin-supporting sheet 3 is supplied from the roll 4 in the form of a web 5, and laminated to the lower surface of the fiber sheet. Thereafter, the upper resin-supporting sheet 5 is unwound from the roll 6 and laminated to the upper surface of the fiber sheet to form a laminated sheet 7. The laminate is hot-pressed with the impregnation roll 8 to transfer and impregnate the resin supported by the sheets 3, 5 to the reinforcing fibers to obtain the prepreg 9, which is cooled immediately with the cooling plate 10 to 10-40 deg.C, preferably <=room temperature. The supporting sheet 5' is peeled, a scrim cloth 14 is placed and laminated 15 to the peeled surface of the laminate, and the product is wound in the form of the roll 13.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to an improvement in a prepreg manufacturing method.

[Prior art]

Conventionally, prepreg is produced by laminating resin carrier sheets coated with B-stage (semi-cured) resin on both sides of reinforcing fibers in the form of strands arranged parallel to each other in a sheet shape, and then impregnating the laminated body. The reinforcing fibers were heated and pressurized with a roll to spread them out, and the reinforcing fibers were transferred and impregnated with a resin-supported resin.

However, in this manufacturing method, the resin is naturally gradually cooled after impregnation, so even if the reinforcing fibers are sufficiently spread and the prepreg surface is extremely smooth immediately after treatment with the impregnation roll, the resin still remains in this state. The temperature is high;
Due to its low viscosity, the force that restricts the shape of the reinforcing fibers is weak.
Since it is not possible to sufficiently prevent the reinforcing fibers from returning to their original strand form, there is a drawback that the prepreg gradually loses its smoothness.

[Purpose of the invention]

An object of the present invention is to prevent deterioration in the smoothness of prepreg.

[Structure of the invention]

The present invention achieves the above object by superimposing sheets on both sides of reinforcing fibers arranged parallel to each other in a sheet shape, and at least one of which is a resin-supporting sheet, and heating and applying the superimposed body with an impregnated roll. A prepreg manufacturing method in which resin is transferred to and impregnated into reinforcing fibers by pressing, characterized in that the obtained prepreg is immediately and actively cooled to 10 to 40°C after the heating and pressure treatment. It is.

Hereinafter, the present invention will be explained with reference to process diagrams shown in the drawings.

In the figure, the reinforcing fibers 1 are fed parallel to each other and in sheet form from the package 2, while the lower copper surface carrying sheet 6
is supplied in the form of a belt from the roll 4, and the resin surface side of the lower support sheet 6 is first superimposed on the lower surface of the notebook-like reinforcing fibers.

Further, the upper resin carrying sheet 5 is fed out from the roll 6, and the resin surface side of the upper resin carrying sheet 5 is superimposed on the upper surface of the sheet-like reinforcing fiber to form a stacked body 7. However, in the present invention, the above two resin support sheets 3
, 5 may be a sheet that does not support resin.

The stacked body 7 is then fed to impregnation rolls 8,8,
The reinforcing edge m1 is heated and pressurized by the impregnating rolls 8, 8 to spread it out, and at the same time, the resin is transferred to and impregnated into the reinforcing fibers 1, and a unidirectional prepreg 9 is formed.

In the present invention, the prepreg 9 thus obtained is immediately and actively cooled to 10 to 4°C, preferably below room temperature.

As the cooling means, an insulating material may be employed, for example, means for blowing cold air, a cooling plate cooled by cold water, etc. are employed.

Although the figure shows a case where the prepreg 9 is cooled from the lower surface by the cooling plate 10, the present invention is not limited to this, and the prepreg can also be cooled from the upper surface, the upper surface of the prepreg, and the lower surface of the prepreg. .

The cooled prepreg 11 is transferred to a take-up roll 12,
12, the sheet 5' constituting the upper resin support sheet 5 is peeled off, and the scrim cloth 14 is superimposed on the peeled surface, and the scrim cloth bonding rolls 15, 15
After being bonded together, it is wound up as a roll 16.

The reinforcing fibers used in the present invention include carbon fibers, glass fibers, organic high modulus fibers such as polyaramid fibers,
High-strength, high-elasticity fibers such as silicon carbide fibers, alumina fibers, and rag fibers, and are usually used in the form of strands.

Such reinforcing fibers may be used alone, or two or more types of fibers, such as carbon fibers and glass fibers, or carbon fibers and organic high-modulus fibers, may be used alternately in the width direction of the prepreg. Or, it is okay to use them in irregular rows.

The resin-supported sheet used in the present invention is made of kraft paper, roll paper, glassine paper, etc. with a thickness of about 0.05 to 0.2 mm, and is coated with clay, starch, polyethylene, or polyvinyl alcohol on one or both sides. Silicone-based or non-7II
A release paper coated with a cone-based release agent, preferably a release agent made of a condensation reaction type or addition reaction type silicone of polyline methyl siloxane and polydimethylhydrodiene siloxane, is used as a sheet, and epoxy resin, unsaturated It is preferable that a thermosetting resin such as polyester resin, ferro resin, polyimide resin, etc. be supported by coating.

These thermosetting resins are in a B-stage (semi-cured) state.

The supported amount of these resins is 20 to 70% by weight in the final prepreg, and 30 to 50% by weight.
Adjusted to make it lighter in weight.

The sheet serves to prevent the arrangement of reinforcing fibers from being disordered in the prepreg manufacturing process and to prevent resin from adhering to rolls and the like.

Furthermore, after the prepreg is manufactured, it is bonded integrally with the prepreg, and serves to prevent the reinforcing fibers from becoming disordered and protect them from moisture absorption until they are used.

The impregnating rolls 8, 8 are used to spread out the strand-shaped sleeve reinforced fibers and impregnate it with resin, and at least one of them is heated to 80 to 180°C, preferably 90 to 150°C.
heated to °C.

Further, the pressurizing force is several kilograms per crn as a linear pressure.

The scrim cloth is an extremely thin cloth made of the above-mentioned reinforcing fibers, and is preferably plain woven or satin woven. In the case of scrim cloth made of carbon fiber or organic high elastic fiber, the thickness is 0.02 to 0.15 mm, preferably 0.02 mm.
-0.05 mm, the basis weight is 10-907/m2, preferably 20-60 fl/2, and in the case of scrim cloth made of glass fiber, the thickness is 0.0
1 to 0.1 mIn, preferably 0.02 to 0.05 mIn,
Area weight: 10-80cm2, preferably 20-50cm2
It is better to be m2. This scrim cloth provides strength in the width direction to the unidirectional prepreg and also serves to prevent the arrangement of reinforcing fibers from becoming disordered.

〔Effect of the invention〕

As described above, in the present invention, the prepreg obtained by heating and pressure treatment with an impregnating roll is immediately and actively cooled to 10 to 40°C. It is possible to prevent the reinforcing fibers once spread out by the rolls from returning to their original strand form. As a result, not only the smoothness of the prepreg surface is improved, but also the disorder of the reinforcing fiber arrangement can be prevented.

Examples of the present invention will be described below.

〔Example〕

A unidirectional prepreg was manufactured by the method described in FIG.

In other words, carbon fiber "Trading Card"T'-3 manufactured by Toshi Co., Ltd.
00 (number of single threads: 6000) was pulled out in parallel to each other in one direction in a sheet shape, and epoxy resins "Epikoat" 1001 and "Epikoat" 828 manufactured by Ciel Epoki 7 Co., Ltd. were applied to both sides of the sorted carbon fibers. Sheets carrying resins mixed at a weight ratio of 8.5:15 (resin loading amount: about 40:2) were superimposed, and the superimposed body was heated with an impregnating roll 8.8 (&tj) at about 125°C.
After being heated and pressurized at a pressure of about 5 kg/cTL), it was immediately cooled to about 20° C. on a cooling plate 10. A cooling plate with a length of 800 rnyn was used while running water at about 10°C.

Note that the traveling speed of the stacked body was approximately 5 m/fj.

After the above treatment, the prepreg surface was peeled off and the prepreg surface was visually observed. It was a state.

[Brief explanation of the drawing]

The figure is a process diagram showing an example of the present invention. 1. Reinforcing fiber, 7. Layered body, 8. Impregnated roll, 9. Prepreg, 10. Cooling plate. Agent Patent Attorney Shin Ogawa - Patent Attorney Ken Noguchi

Claims (1)

[Claims] On both sides of the reinforcing fibers arranged parallel to each other in a sheet shape,
In a prepreg manufacturing method, sheets of which at least one of the resin and resin-supported sheets are stacked, and the stacked body is heated and pressurized with an impregnating roll to transfer and impregnate the reinforcing fibers with the resin. A method for manufacturing a prepreg, which comprises actively cooling the prepreg to 10 to 40°C immediately after the heating and pressure treatment.