JPS6193868A - Preparation of resin impregnated base material - Google Patents

Abstract

PURPOSE:To make it possible to freely control the quantity of the resin of a resin impregnated base material in the lateral direction thereof, by providing temp. difference to opposed plates or rolls and changing the gap therebetween in the lateral direction. CONSTITUTION:A slitter has a plate or roll shape. In the roll shaped slitter, a pair or rolls 1a, 1b are mounted and comprise a material such as a metal, for example, iron or stainless steel or reinforced plastics. When the quantity of the resin at the central part of a base material 2 in the lateral direction thereof is desired to be made much, to the sides opposite to the sides, which are contacted with resin varnish, of the roll 1a, 1b of the slitter, gas or a liquid A having temp. higher than that of the roll at least contacted with the resin varnish is blown. By this method, the roll 1a, 1b generate temp. difference therein and are bent by expansion and the gap between the central parts of the rolls 1a, 1b becomes wide to increase the quantity of the resin at the central part.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a method for continuously impregnating a base material for a laminate board or a base material for an adhesive sheet with a resin varnish, which allows the amount of resin to be freely controlled in the width direction of the base material. It is related to.

[Prior art]

Decorative building materials, laminates for decorative furniture, copper-clad laminates for printed circuits,
Circuit laminates, electrical insulation laminates, etc. made by the additive method are manufactured by impregnating various base materials with various resin varnishes and drying them, then stacking one or more prepregs and stacking them under heat and pressure. . Adhesive sheets used for building materials, automobiles, aircraft, electrical products, etc. are also manufactured by impregnating various types of resin varnishes into various food base materials and drying them.

Both prepregs and adhesive sheets for laminates are made of long base materials rolled into rolls, and these base materials unwound from the rolls are coated continuously by a kiss coating method, a dip method, etc. It is manufactured by impregnating it with resin varnish and then drying it.

One of the heaviest factors when manufacturing prepregs and adhesive sheets for these laminates is the distribution of the amount of resin in the width direction of the base material and the impregnation of the long base material in the form of a roll.
It should not change from the beginning to the end of drying.

If the distribution of the amount of resin in the width direction of the base material or the amount of resin relative to the base material changes during continuous impregnation and drying, it will not be possible to obtain a laminate with a uniform and good appearance over the entire surface of the prepreg for laminates. Moreover, a laminate with partially degraded electrical and mechanical properties is obtained. Moreover, even with adhesive sheets, stable adhesion cannot be obtained over the entire surface.

Therefore, in order to keep the distribution of the resin amount in the width direction of the base material and the amount of resin relative to the base material constant from the beginning to the end of the impregnation and drying process, the base material sufficiently impregnated with resin varnish is made into a plate shape, an i °-" shape or a deformed ° It is industrially practiced to pass through a -′-shaped 5-star gap.

However, with these slitters, it is not possible to easily change the distribution of resin amount in the width direction of the base material. If it is to be changed, for example, it is necessary to replace the gap between the slitters with one made in accordance with the desired distribution of resin amount in the width direction of the base material.

In addition, in these slitters, at the same time that resin varnish impregnation is started, the slitter is locally cooled due to latent heat of evaporation due to evaporation of the varnish solvent that comes into contact with the slitter, and the gap between the slitters gradually changes. Therefore, the distribution of the amount of resin in the width direction of the base material and the amount of resin relative to the base material gradually change, causing the various problems described above in practice.

[Purpose of the invention]

The present invention conventionally involves changing the distribution of the amount of resin in the width direction of the substrate during resin impregnation and drying into a roll-shaped substrate, and also making the amount of resin constant in the width direction from the beginning of the impregnation and drying process to the end. However, by creating a temperature difference in the slitter, it was possible to easily change the resin amount distribution in the width direction of the substrate, and also to make it possible to keep the resin amount constant in the width direction. Based on this knowledge, we proceeded with various studies and completed the present invention.

[Structure of the invention]

The present invention provides a method for continuously impregnating a base material with resin varnish.
This invention relates to a method for continuously impregnating a base material with resin varnish, which is characterized by controlling the amount of resin in the width direction of the base material by applying a temperature difference to a slitter that controls the amount of resin applied to the base material.

Resins for laminates or adhesive sheets used in the present invention include thermosetting resins such as phenol resins, melamine resins, area resins, epoxy resins, diallyl phthalate resins, unsaturated polyester resins, polyimide resins, and polybutadiene resins. . Base materials for laminates and adhesive sheets include fiber base paper, cotton cloth, cotton non-woven fabric, synthetic fiber cloth, synthetic fiber non-woven fabric, asbestos cloth, asbestos paper, glass cloth,
These include glass fiber non-woven fabrics and paper made from a mixture of cellulose and glass fibers.

1 to 3 show the apparatus used in the present invention.

The shape of a slitter may be a plate, a roll (cylindrical), or a deformed roll such as a comma roll. Figure 1 shows the case of a roll-shaped slitter, with a pair of rolls (1 m),
(lb). Generally, the gap between opposing plates or rolls is the same in the width direction in a normal atmosphere, but of course this gap does not necessarily have to be constant. Materials include metals such as iron, stainless steel, and phosphor bronze, and plastics such as reinforced plastics. By creating a temperature difference in the slitter, that is, opposing plates or rolls, and changing the gap in the width direction between these opposing plates or rolls, the amount of resin in the width direction of the base material can be changed. The temperature difference may be applied to both opposing plates or rolls, or only to one side.゛If you want to increase the amount of resin in the center part in the width direction of the base material, as shown in Figure 2, add at least a plate or roll that is in contact with the resin varnish on the opposite side of the slitter plate or roll that is in contact with the resin varnish. If the roll is sprayed with a gas or liquid (2) that has a higher temperature than the roll, or in the case of a liquid, it is brought into contact.

By doing this, the plate or roll used as a slitter will create a temperature difference within the plate or roll, and due to thermal expansion, the gap in the center of the slitter will become wider. The amount increases. Around the base material,
If you want to increase the amount of resin in the center part, you can do so by increasing the temperature difference within the plate or roll. In the case of a liquid, it is necessary to provide a wall to prevent it from coming into contact with the varnish-impregnated substrate, and it is preferable to collect and reuse the liquid. On the other hand, if you want to reduce the amount of resin in the central part of the base material, at least increase the temperature of the plate or roll that is in contact with the resin varnish on the opposite side of the slitter plate or roll that is in contact with the resin varnish. (low-temperature gas or liquid) or, in the case of liquid, contact.

In this case, the plate or roll used as the slitter will shrink due to heat, and the gap in the center of the bent slitter will become narrower.
The amount of resin in the center part is reduced.

If it is desired to reduce the amount of resin in the central part of the base material compared to the periphery of the base material, this can be done by increasing the temperature difference within the plate or roll.

It is preferable to use heated air or cooled air as the gas.

When the resin varnish starts to come into contact with the plate or roll used as a slitter, the temperature of the contact surface gradually decreases due to the latent heat of vaporization of the solvent in the varnish, and the slitter gap changes, so the amount of resin in the width direction of the base material will also change.

Therefore, in order to keep the amount of resin in the width direction constant from the beginning to the end of varnish impregnation and drying, it is industrially easy to adjust the gap by creating a temperature difference in the plate or roll used as the slitter. It becomes a method.

Furthermore, the gap between the slitters is measured continuously in the width direction of the impregnating and drying process at both ends and the center, or at several additional positions, and the temperature difference is adjusted so that the gap between the slitters remains constant from the beginning to the end of the impregnating and drying process at each position. It is highly preferable to put it on.

In this case, the amount of resin in the central portion of the base material is reduced.

〔Effect of the invention〕

With the apparatus of the present invention, it is possible to freely change the amount of resin in the width direction of the substrate in all kinds of resin-impregnated substrates for laminates and resin-impregnated substrates for adhesives, and also to change the amount of resin with respect to the substrate and The distribution in the width direction can be kept constant from the beginning of resin varnish impregnation and drying to the end.
Can prevent molding special resin from flowing out when manufacturing laminates,
It is of great industrial value as it allows the production of laminates with uniform performance over the entire surface. Adhesive sheets are also highly industrially valuable because they are effective in preventing resin from flowing out from the periphery during heat bonding, and adhesives with uniform adhesiveness can be obtained over the entire bonding surface.

〔Example〕

The invention will now be illustrated by examples.

Example - A resin varnish made of a 50% methanol-toluene mixed solution of Luzole-type tung oil-modified phenolic resin was weighed [140t/m1
In order to impregnate and dry kraft paper with a width of 11,000 W and obtain resin-impregnated paper with a resin content of 52% and a volatile content of 6 cm in the central part of the base material, a slitter with a chrome-plated iron roll with a diameter of 330 mm and a length of 1,600 m is used. Using an impregnating device, heated air at 50° C. was blown onto each of the two rolls serving as a slitter on opposite sides of the rolls in contact with the resin-impregnated varnish to impregnate and dry the resin varnish, thereby obtaining a resin-impregnated base material. .

The distribution of the resin amount in the width direction of the resin-impregnated base material obtained by K is 100 at the center and 95 to 97 at both ends.
A resin-impregnated base material with a large amount of resin in the central portion was obtained. When a laminate made by stacking several resin-impregnated substrates was heated and pressure-molded using a press, a laminate with good press workability and good press workability was obtained with very little resin flowing out to the surrounding areas during molding. Ta.

Comparative Example-1 In Example-1, impregnation and drying were performed without blowing heated air at 50° C. to the slitter.

The amount of resin in the width direction of the obtained resin-impregnated base material is the same at the center and both ends at the start of impregnation and drying, but gradually the amount of resin in the center increases. ,
It becomes 98-99 at both ends.

When a laminate consisting of several layers of resin-impregnated base materials was heated and pressure-molded using a press, a large amount of resin leaked out to the periphery of the molding area, and the amount of resin flowing out varied depending on the press stage of the multi-stage press. In addition, due to the contamination of powder from the cured resin material that leaked out into the surrounding areas, laminates with poor appearance were obtained, resulting in a decrease in the yield of non-defective products.

[Brief explanation of the drawing]

1, 2, and 3 are schematic diagrams of the apparatus used in the present invention, and FIG. 1 is a longitudinal sectional view of a roll-shaped slitter. 2 and 3 are sectional views taken along the line A in FIG. 1. Second
The figure shows the width direction of the base material, when the amount of resin in the center part is large,
FIG. 3 shows a case where the amount of resin in the central portion is small. 1m11b・・・・・・Rolled slitter 2・
...Resin varnish impregnated base material 3...
...Resin varnish A scraped off with a slitter...
...Heating gas or liquid B...Cooling gas or liquid Fig. 1 Fig. 2 C Fig. 3

Claims (5)

[Claims] (1) A method for continuously impregnating a base material with resin varnish, which is characterized by controlling the amount of resin in the width direction of the base material by applying a temperature difference to a slitter that controls the amount of resin applied to the base material. continuous impregnation method with resin varnish. (2) A method for continuous impregnation with a resin varnish according to claim 1, characterized in that a temperature difference is created by blowing gas onto the slitter. (3) The method for continuously impregnating a resin varnish according to claim 1, wherein a temperature difference is created by blowing heated air or cooled air onto the slitter. (4) A method for continuous impregnation with a resin varnish according to claim 1, characterized in that a temperature difference is created by spraying a liquid onto the slitter or by bringing the liquid into contact with the slitter. (5) A method for continuous impregnation with resin varnish according to claim 1, characterized in that while continuously measuring the gap between the slitters, a temperature difference is applied so that the gap between the slitters becomes constant over time during impregnation.