JPH02293128A - Preparation of laminated sheet - Google Patents

Abstract

PURPOSE:To reduce not only the dimensional change rate of a laminated sheet at the time of the processing thereof but also the irregularity of the dimensional change rate in the plane of the laminated sheet by laminating a plurality of prepregs to hold the same between metal plates and molding the laminated prepregs under heating and pressure to immediately separate the formed laminated sheet and quenching the laminated sheet in a non-pressure state. CONSTITUTION:Fibrous base materials are impregnated with a thermosetting resin and dried to form a prepreg. A plurality of the prepregs thus formed are laminated to be held between metal plates and molded under heating and pressure. Immediately thereafter, this laminated sheet is separated from the metal plates and quenched in a non-pressure state to obtain a desired laminated sheet. By this method, the dimensional change rate of the laminated sheet at the time of the processing thereof can be reduced and the irregularity of the dimensional change rate in the plane of the laminated sheet can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION <<Industrial Application Field>> The present invention relates to a method for manufacturing a laminate such as a copper-clad laminate used for electrical equipment, electronic equipment, computing equipment, communication equipment, etc.

<Prior Art> Conventionally, in the manufacturing process of laminates such as copper-clad laminates, as shown in JP-A No. 62-50305, a method of lowering the pressure during cooling after hot-pressing molding, or a special method has been used. Kaisho 5
As shown in Japanese Patent Application Laid-open No. 9-85750, there is a method in which the pressure is temporarily released during the cooling process and then a specific pressure is applied again to cool the product. Water cooled under pressure for 5-10 minutes to bring the internal temperature to 130
There is a method in which the pressure is released after cooling to ~150°C and the laminate is left to cool until the temperature of the laminate reaches room temperature.

《Problem to be solved by the invention》 However, JP-A-59-85750 and JP-A-59
In the method shown in No. 41262, since the molded laminate is cooled while being sandwiched between metal plates, a pressure difference is created in the plane due to the difference in the thickness of the formed laminate, and the dimensional change rate of the laminate is reduced. This may cause problems such as variations depending on the position within the plate surface, and the effect of reducing the dimensional change rate is small. In addition, since the process from the heating and press molding process to the cooling process is performed continuously in the same press machine, there were problems such as poor production efficiency.

In view of the above-mentioned problems, the present invention provides a method for manufacturing a laminate that is excellent in both the high degree of dimensional stability required for fine patterning in recent processing of laminates and improved production efficiency. .

<Means for Solving the Problems> The method for producing a laminate according to the present invention uses a prepreg laminate made by impregnating a fibrous base material with a synthetic resin and drying it as a substrate material, and optionally injects copper into the laminate. It is characterized by stacking the foils, sandwiching them between metal plates, curing them under heat and pressure, and then immediately cooling them rapidly under no pressure.

The manufacturing method of the present invention will be explained in detail. The base material used in this invention is a fabric made of synthetic fibers such as polyamide and polyester, inorganic fibers such as glass, asbestos, and natural fibers such as paper, either alone or in a blend, or a nonwoven fabric, paper, or fibers bound together with a synthetic resin binder. etc. are used. Resins include thermosetting resins such as epoxy resins, phenol resins, polyester resins, melamine resins, and polyimide resins. There are no particular limitations on the material, thickness, surface roughness, etc. of the copper foil and metal plate (mold plate).

Using these base materials, resin and copper foil, 14
0~210°C, 5~150kg/cr#, 40~12
Manufactured by heating and pressurizing for 0 min to integrate.

In order to improve dimensional stability, plate thickness accuracy, and warpage, it is preferable to form at as low a pressure as possible.

The present invention is characterized in that the component is taken out from the press immediately after heating and pressurization is completed, the laminate is disassembled from the mold plate, and the laminate is rapidly cooled under no pressure. The method of rapid cooling is not particularly limited, and any method may be used, such as a method of blowing low-temperature gas such as fluorine gas or carbon dioxide gas, or a method of immersing it in a low-temperature liquid such as water or liquefied gas liquid.

Note that it is preferable to uniformly cool both sides of the laminate.

<<Function>> In the method for manufacturing a laminate according to the present invention, after heating and pressing in the press is completed, the laminate is cooled uniformly under no pressure, so that the stress inside the laminate is uniformly released.
The laminate is free to shrink at the end of molding. Furthermore, since cooling is not performed within the same press, the press can be used exclusively for heating and pressurizing, improving productivity and reducing energy consumption such as steam and electricity.

By cooling the laminate in this manner, it is possible to obtain a laminate that has a small dimensional change rate during processing of the laminate and small variations in the dimensional change rate at various parts within the laminate.

<<Example>> Hereinafter, the present invention will be described in detail based on Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 Thickness 0. A 2 mm glass woven fabric was impregnated with an epoxy resin containing a curing agent and dried to obtain a pre-reg with a resin content of 45%. 8 sheets of this Bripreg are stacked on both sides with a thickness of 0.
018 mm copper foil was placed between the metal plates and molded at a pressure of 60 kg/cI# and a temperature of 170° C. for 90 minutes.

After that, the component with the metal plate and molded product still stacked was taken out of the press, the laminates were disassembled one by one, and immediately introduced into 10℃ water until the surface temperature of the laminate reached 20℃. It was rapidly cooled to obtain a copper-clad laminate having a thickness of 1.6 mm.

Comparative Example 1 A laminate having the same structure as in Example 1 was molded under heat and pressure under the same conditions, and the cooling pressure was reduced to 1.5 kg/c- and water-cooled to room temperature, resulting in a thickness of 1.5 kg/c. A 6 mm copper-clad laminate was obtained.

Comparative Example 2 A laminate having the same structure as Example 1 was heated and pressure molded under the same conditions, the pressure was temporarily released during cooling, and then the laminate was heated to 5 kg/cm again.
By applying a pressure of J and cooling with water to room temperature, the thickness is 1.
A copper clad laminate of No. 61 was obtained.

Dimensional changes were measured for each of the copper-clad laminates from Example 1 to Comparative Example 2.

Measurement is 250 x 250 mm from the center and edge of the laminate.
A test piece was cut out, the initial dimensions were measured, and then the entire surface of the copper foil was etched and heated at 150℃ for 60 minutes.
The dimensions after the heat treatment for 1 minute were measured, and the dimensional change rate after the heat treatment was determined. The results are shown in the table.

<<Effects of the Invention>> The laminate manufactured according to the present invention is uniformly rapidly cooled under no pressure after being heated and pressurized, so that the dimensional change rate during processing of the laminate is small, and the dimensional change rate in the plane of the laminate is low. It is also possible to obtain a laminate with small variations in . Printed circuit boards made from this laminated board do not require correction during pattern processing, and defects caused by fine pattern misalignment can be greatly reduced. Furthermore, since cooling is not performed in the same press device, molding time can be shortened, and production efficiency and energy savings can be achieved.

Claims (1)

[Claims] 1. A fibrous base material is impregnated with a thermosetting resin, a plurality of dried prepregs are laminated and sandwiched between metal plates, and after molding under heat and pressure, the laminate is immediately dismantled from the metal plates and then molded under no pressure. A method for producing a laminate, characterized by rapid cooling.