JPH01314146A - Preparation of preform of fiber reinforced plastic sheet - Google Patents

Abstract

PURPOSE:To obtain a preform containing a resin powder and a chopped fiber (CF chop) uniformly without irregularity and having uniform physical property values by sucking the chopped fiber and the resin powder to a mold to form the preform and spraying the powder to the preform before applying a binder thereto while evacuating the mold. CONSTITUTION:When a preform mold 1 is inserted in a chop tank 2 having cut CF chop 3 received therein and a vacuum chamber 5 is reduced in pressure by an exhaust fan 4, the preform mold 1 is also reduced in pressure and the CF chop 3 is sucked to the preform mold 1. In this case, the CF chop 3 is successively sucked to a place where no CF shop is sucked or the sucking amount of the CF chop 3 is little to form a layer having a uniform thickness. Next, a nylon powder is sprayed to the preform mold 1 under reduced pressure. After the spraying of the powder is finished, a nylon solution prepared by diluting a 20% solution of alcohol soluble nylon in methanol to 5% is sprayed while reduced pressure is further held to be sufficiently infiltrated in and adsorbed by the CF chop layer of the preform. Further, reduced pressure is held to remove a solvent and the preform is dried and solidified.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing an FRP preform used for manufacturing a reinforced plastics (hereinafter referred to as FRP) molded article.

(Prior art) In the conventional preform manufacturing method, the preform was manufactured by scattering chop powder and resin powder onto the preform mold using a scattering method, but this conventional method was slow in manufacturing speed. , powder, and chop charges were large, and the physical properties of the preform were also low.

(Problem to be solved by the invention) The present invention speeds up the preform production speed,
Reduces variation in powder and chop charges,
It is an object of the present invention to provide a method for manufacturing a preform that improves the uniformity of the molded body.

(Means for Solving the Problems) The present invention installs a preform mold in a decompression chamber equipped with an exhaust machine, places a pre-cut chopstick in a tank, inserts the preform mold into the tank, and turns on the exhaust machine. When activated, the pressure inside the vacuum chamber and the preform mold is reduced, and the chopped grains in the tank are lifted up and adsorbed to the preform mold, causing unsolidified chopped grains made of a layer of chopped grains to be deposited on the surface of the preform mold. The method is characterized in that a preform is formed, then resin powder is sprayed onto the preform in this state and adsorbed thereon, and then a binder is applied and dried under reduced pressure to solidify the powder and the chopped resin. This is a method for manufacturing a preform.

(Function) According to the present invention, first of all, T. spp. is adsorbed onto the preform mold by reduced pressure.

The scattering method is a method in which it is selectively adsorbed to the unattached portions of the CF chop of the mold.

Therefore, it is preferentially adsorbed to areas where the amount of kidney I adhesion of the chops is small, that is, the thickness of the adhesion of the chops. However, in the conventional dispersion method, the chops do not selectively adhere to areas where Ff1 adhesion has not occurred. Because of this, the thickness of the preform is not uniform.

By adsorbing the chopped powder and resin powder onto the mold in this order to form a preform, sufficient resin impregnation is achieved.

Furthermore, in the present invention, by applying the binder while reducing the pressure inside the mold after spraying the powder, the binder can be applied to the preform, and moreover, the binder can be sufficiently permeated into the preform. be exposed.

Then, the binder is well dried, the binder is solidified, and a preform is manufactured.

(Example) Examples will be described with reference to the drawings.

In FIG. 1, an exhaust air 894 is installed in the decompression chamber 5.

Further, a preform mold 1 is provided, and a preform mold 1 is provided.
A honeycomb layer 9 is provided between the exhaust fan 4 and the exhaust fan 4 for rectification.

The cut tank 2 contains cut CF chops 3.

When the preform mold is inserted into the chop tank and the pressure is reduced in the decompression chamber using an exhaust fan, the pressure inside the preform mold is also reduced and the CF
Chop 3 is adsorbed onto the preform mold.

In this case, CF chips are successively adsorbed in areas where CF chops are not adsorbed or where the amount of adsorption is small, forming a layer of uniform thickness.

The preform is then sprayed with Nylon 6 powder while continuing the vacuum.

After spraying the powder, while continuing to reduce the pressure, apply alcohol-soluble nylon (registered trademark of Toshi Co., Ltd. A-
A nylon solution prepared by diluting a 20% methanol solution of 70> to 5% is sprayed to sufficiently impregnate and adsorb the CF chop layer of the preform.

Further, the pressure is continued to be reduced to remove the solvent, and it is dried and solidified to consist of CF chops and nylon powder (solidified).
A preform was manufactured.

(Effects) The preform produced by the method of the present invention has uniform powder and CF chop, no variation, uniform physical property values of the preform, and high production speed, making it extremely effective.

[Brief explanation of the drawing]

FIG. 1 is an embodiment showing the manufacturing method of the present invention. FIG. 2 is a front view of the obtained preform, showing an embodiment in which the vertical wall portions are sprayed with powder. 1... Preform type, 2... Chop tank, 3
...CF chop, 4...exhaust fan, 5...
・Decompression chamber, 6...Honeycomb layer, 7...Powder spray. Patent Applicant: Honda Motor Co., Ltd. Engraving of the drawings (no changes in content) Figure 1 Figure 2 Procedural Sleeve (Method) % Formula % 1゜Indication of Incident 1986 Patent Application No. 143682 2, Invention Name: Manufacturing method for preforms for reinforced plastic sheets 3, person making the amendment Patent applicant address: 2-1-1 Minami-Aoyama, Minato-ku, Tokyo Name: Honda Motor Co., Ltd. Representative: Koreshi Kume 4, Agent: 107 ('@ Story 582-7211) August 30, 1988 (Shipping mortar) 6. Subject of amendment The field and date of the power of attorney's terms of reference, and drawings (1) Due to a mistake, I omitted the place where I should have written "patent application", which is a matter mentioned above, so I am correcting it as shown in the attached sheet. (2) In the power of attorney, the date of delegation was omitted due to an error, so we have corrected it as shown in the attached sheet. (2) The drawing was clearly drawn in sufficiently deep black and corrected as shown in the attached sheet. (No change in content) 8. List of attached documents

Claims (1)

[Claims] 1. Place the preform mold in a vacuum chamber equipped with an exhaust fan, put the pre-cut chopsticks into the tank, insert the preform mold into the tank, operate the exhaust fan, and remove the preform from the vacuum chamber. The pressure inside the mold is reduced, and the chopped fibers in the tank are adsorbed onto the preform mold, forming an unsolidified preform consisting of a chopped fiber layer on the surface of the preform mold. Then, in this state, the resin powder is added to the preform. A method for producing a preform, which is characterized by spraying onto the foam and adsorbing it, and then applying a binder under reduced pressure and drying it to solidify the chopped powder together with the powder.