JPH03111431A - Production of prepreg sheet - Google Patents

Abstract

PURPOSE:To produce a prepreg sheet contg. no remaining air bubble causative of a quality degradation of an FRP molded article by previously impregnating, into a fibrous reinforcement, a monomer which is a component of a resin compsn. to be impregnated and then impregnating the resin compsn. into the reinforcement. CONSTITUTION:In producing a prepreg sheet by impregnating a photocurable or thermosetting unsatd. polyester resin compsn. into a fibrous reinforcement, a monomer which is a component of the resin compsn. is previously impregnated into the reinforcement, and then the resin compsn. is impregnated. For instance, a part of styrene which is a crosslinkable monomer contained in the photocurable or thermosetting unsatd. polyester resin compsn. is previously impregnated into the reinforcement.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing a prepreg sheet for obtaining an FRP molded article.

(Prior Art) Prepreg sheets obtained by impregnating a reinforcing fiber material such as a glass fiber mat with a photo- or thermosetting unsaturated polyester resin liquid are widely used in the production of various FRP molded bodies.

Such prepreg sheets are generally manufactured by the following method. That is, applying a photo- or thermosetting unsaturated polyester resin liquid to a reinforcing fiber material such as a glass fiber mat, or
Alternatively, a reinforcing fiber material such as a glass fiber mat is immersed in a photo- or thermosetting unsaturated polyester resin liquid, and this layer or more of the reinforcing fiber material is pressed and transferred with a pair of presser rolls, thereby applying resin to the reinforcing fiber material. It is manufactured by impregnating it with a liquid, adjusting the thickness, and then drying it if necessary.

The prepreg sheet produced in this way may be subsequently transferred to the FRP molded product manufacturing process, or may be once coated with a protective film on its surface and wound up for storage.

(Problems to be Solved by the Invention) However, in the conventional prepreg sheet manufacturing method as described above, it is difficult to uniformly impregnate the entire reinforcing fiber material with a photo- or thermosetting unsaturated polyester resin liquid.
The resin liquid partially stops passing through the reinforcing fiber material, so that sometimes air bubbles remain in the reinforcing fiber material.

When a prepreg sheet with remaining air bubbles is shaped into a desired shape, for example, by vacuum forming, and the resin is cured to produce various FRP molded bodies, FRP due to the air bubbles is formed.
There are problems in that the surface condition of the RP molded product deteriorates, and air bubbles concentrate at the corner portions of the FRP molded product, resulting in the formation of missing parts with little resin, resulting in a decrease in quality.

The present invention solves the above-mentioned problems, and its purpose is to provide a method for producing a prepreg sheet that does not leave any air bubbles that would cause deterioration in the quality of an FRP molded product.

(Means for Solving the Problems) In the method for manufacturing a prepreg sheet of the present invention, when manufacturing a prepreg sheet by impregnating a reinforcing fiber material with a photo- or thermosetting unsaturated polyester resin liquid, the reinforcing fiber material is preliminarily applied to the reinforcing fiber material. The method is characterized in that the resin liquid is impregnated after the monomer serving as a component of the resin liquid is impregnated, thereby achieving the above object.

The method of the present invention will be explained below with reference to the drawings.

In FIG. 1, numeral 10 denotes a protective film that is unwound from the roll, and for example, a transparent polyvinyl alcohol film is suitably used.

Reference numeral 20 is a reinforcing fiber material that is unwound from the rolled body, and generally a light-transmitting and strong glass fiber non-woven fabric or woven fabric is used, but other reinforcing fiber materials that do not inhibit light transmission and are strong are also used. Available for use.

The protective film 10 is sent to an applicator 30, such as a coating applicator, where one side (top side) of the protective film 10 is coated.
A photo- or thermosetting unsaturated polyester resin liquid is applied to the surface. The photocurable unsaturated polyester resin liquid is generally a liquid mixture of a liquid unsaturated polyester resin, a crosslinking monomer such as styrene, and a photocuring agent such as 2,2-dimethoxy-2-phenylacetophenone. belongs to. Further, the thermosetting unsaturated polyester resin liquid is a liquid containing a thermosetting agent such as benzoyl peroxide instead of the above photocuring agent.

The reinforcing fiber material 20 is sent to a coating machine 40 such as a spray coating machine, where a crosslinking agent such as styrene, which is a component of the resin liquid, is sprayed onto the reinforcing fiber material 20.

The nitrate is in a liquid state and can be easily impregnated into the reinforcing fiber material 20 uniformly as a whole.

In the prior art, a photo- or thermosetting unsaturated polyester resin liquid usually contains about 25 to 40% by weight of a crosslinking monomer such as styrene. In the present invention, when the reinforcing fiber material 20 is impregnated with a crosslinking monomer such as styrene, which is a component of the resin liquid, about 5 to 10% by weight of a crosslinking monomer such as styrene is added to the resin liquid actually used. The remaining 20
Preferably, about 30% by weight of a crosslinking monomer such as styrene is used to impregnate the reinforcing fiber material 20.

The protective film 10 coated with the resin liquid and the reinforcing fiber material 20 impregnated with the monomer are stacked and passed through a pair of presser rolls 50 and 51, and are transferred while being pressed by the presser rolls 50 and 51. , the reinforcing fiber material 20 is thoroughly impregnated with resin liquid and the thickness is adjusted. In this way, a prepreg sheet 60 having the protective film 10 adhered to one side (lower side) is manufactured.
゛ and reinforcing fiber material 20°, using photo- or thermosetting unsaturated polyester resin liquid resin liquid and monomer, and coating application 4ffi30' and spray coating machine 4 similar to the above.
0° and use a protective film 10 on one side (top side).
After that, a prepreg sheet 60° coated with prepreg sheet 60 and prepreg sheet 60
' are piled up as shown and pressed by a pair of pressing pinch rolls 70, dried if necessary, and then taken up and wound up by a pair of take-up pinch rolls 71.

In this way, a prepreg sheet laminate 66 having protective films 10, 10' applied to both surfaces is manufactured.

The protective films 10, 10' are releasably adhered to the surfaces thereof due to the adhesive properties of the prepreg sheets 60 and 60''.

The thickness of the prepreg sheet is generally about 1 to 6 cylinders. When manufacturing a thick prepreg sheet, prepreg sheet 60 and prepreg sheet 6 are used as described above.
It is preferable to manufacture a laminate 66 with a thickness of 0''. However, when manufacturing a thin prepreg sheet, the prepreg sheet 60 or 60' is preferably manufactured without laminating the prepreg sheet 60 or 60'.
This can be omitted in the manufacturing process for either the Bripreg sheet 60 or 60''.

Laminate 6 of prepreg sheets manufactured in this way
6, or the prepreg sheet 60 or 60° is not rolled up and stored as shown in the figure, but is subsequently made into FRP.
It can also be transferred to a molded body manufacturing process.

(Function) As in the present invention, when the reinforcing fiber material is impregnated in advance with the monomer that is a component of the photo- or thermosetting unsaturated polyester resin liquid, the above-mentioned 7-mer has good impregnating properties and is uniformly applied to the reinforcing fiber material. Impregnated. Then, when the reinforcing fiber material is impregnated with the resin liquid, the resin liquid is well mixed into the seven-layer mixture, and the resin liquid is evenly spread throughout the reinforcing fiber material, and the resin liquid is evenly spread throughout the reinforcing fiber material. There are no areas where the resin liquid does not pass through.

(Example) Examples and comparative examples of the present invention are shown below.

In this example, a prepreg sheet laminate 66 was manufactured by the method shown in FIG.

First, 100 parts by weight of an unsaturated polyester resin liquid (#2064 manufactured by Ni-Showa Kobunshi Co., Ltd.) was mixed with 0.5 parts by weight of a photocuring agent (Irgacure #651 manufactured by Nippon Ciba Geigy Co., Ltd.) to form a photocurable non-curing agent. A saturated polyester resin liquid was prepared. Note that this photocurable unsaturated polyester resin liquid contained about 10% by weight of styrene monomer.

Apply this photocurable unsaturated polyester resin liquid to a thickness of 65 μm.
It was coated on one side (top side) of a transparent polyvinyl alcohol film 10 to a thickness of about IM.

On the other hand, a reinforcing fiber material 20 made of glass fiber strand mat #450 was impregnated with styrene monomer to such an extent that the whiteness of the glass fiber mat disappeared. In this case, the styrene monomer impregnated into the reinforcing fiber material 20 corresponds to about 30% of the total monomers contained in the photocurable unsaturated polyester resin liquid.

A prepreg sheet 60 was produced in this manner, a prepreg sheet 60' was produced in the same manner, and the prepreg sheets 60 and 60 degrees were laminated to produce a laminate 66 of prepreg sheets.

This prepreg sheet laminate 66 had no air bubbles and was transparent and beautiful. Using this prepreg sheet, various FRP molded bodies were produced by shaping the prepreg sheet into a desired shape using a vacuum forming method and curing the resin. never occurred.

1 fake 1 In Example 1, a photocuring agent (Irgacure $651:
0.5 parts by weight (manufactured by Nippon Ciba Geigy) was added to 2 parts by weight of benzoyl peroxide (Bercure 0: NOF type), which is a thermosetting agent.
The same procedure as in Example 1 was carried out except that parts by weight were changed.

In this case as well, the obtained prepreg sheet laminate 66 had no air bubbles and was transparent and beautiful. Using this prepreg sheet, after forming it into a desired shape using a vacuum forming method, the resin is cured and various F.
An RP molded body was produced, but there were no air bubbles in this FRP molded body, and no air bubbles were generated at some of the corners.

This five shells ↓ In this comparative example, a laminate of prepreg sheets was manufactured using a conventional method.

First, 100 parts by weight of an unsaturated polyester resin liquid (#2064, manufactured by Showa Kobunshi Co., Ltd.) and 0.5 parts by weight of a photocuring agent (Irgacure #651, manufactured by Nippon Ciba Geigy) were mixed to form a photocurable non-curing agent. A saturated polyester resin liquid was prepared. Note that this photocurable unsaturated polyester resin liquid contained about 40% by weight of styrene monomer.

Next, two reinforcing fiber materials made of glass fiber strand mat #450 are prepared, and these two reinforcing fiber materials are immersed in a bath of the photocurable unsaturated polyester resin liquid to form two layers of resin impregnation. A reinforced fiber material is made, and the two layers of resin-impregnated reinforced fiber material are pressed and transferred with a pair of presser rolls to thoroughly impregnate the reinforcing fiber material with resin liquid and adjust the thickness, resulting in a prepreg sheet laminate. was manufactured. In addition, a transparent polyvinyl alcohol film having a thickness of 65 μm was applied as a protective film to both sides of this prepreg sheet laminate.

Many air bubbles were observed in the obtained prepreg sheet laminate. Using this prepreg sheet, the desired shape is formed using a vacuum forming method, and then the resin is cured to form various FRs.
A P molded body was manufactured, but air bubbles were concentrated in some corners of this FRP molded body, resulting in a lack of resin.

Comparative Example 1 In Comparative Example 1, a photocuring agent (Irgacure #651:
2 parts by weight of benzoyl peroxide (Percure 0: manufactured by Nippon Oil & Fats), which is a thermosetting agent.
The same procedure as in Example 1 was carried out except that parts by weight were changed.

In this case as well, the obtained prepreg sheet laminate has
Many air bubbles were observed. Using this prepreg sheet, various FRP molded bodies were produced by shaping the prepreg sheet into a desired shape using a vacuum forming method, and then curing the resin. There was a small area of missing flesh.

(Effects of the Invention) As described above, in the method for manufacturing a prepreg sheet of the present invention, when manufacturing a prepreg sheet by impregnating a reinforcing fiber material with a photo- or thermosetting unsaturated polyester resin liquid, the above-mentioned The resin liquid is impregnated with the monomer that is a component of the resin liquid, and then the resin liquid is impregnated with the resin liquid. When this method is adopted, the resin liquid spreads uniformly throughout the reinforcing fiber material, and no air bubbles are formed in the prepreg sheet. There is no leftover.

Therefore, using such prepreg sheets, FRP
When producing a molded object, FRP does not deteriorate in quality due to air bubbles.
A molded body can be obtained.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of the method for manufacturing the prepreg sheet of the present invention. 10.10'...protective film, 20.20'...
Reinforced fiber material, 30.30'...coating applicator,
40.40'...Spray coating machine, 50.51.50
゛, 51"...presser roll, 60.60"...prepreg sheet, 70...pressing pinch roll, 71...
- Pick-up pinch roll, 66... prepreg sheet laminate.

Claims (1)

[Claims] 1. When manufacturing a prepreg sheet by impregnating reinforcing fiber material with a photo- or thermosetting unsaturated polyester resin liquid,
A method for manufacturing a prepreg sheet, comprising impregnating the reinforcing fiber material with a monomer that is a component of the resin liquid in advance, and then impregnating it with the resin liquid.