JPS59184643A - Unsaturated polyester resin laminated board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an unsaturated polyester resin laminate that has excellent mechanical strength and exhibits small dimensional changes during heating and humidification treatments.

Conventionally, copper-clad laminates and laminates made of glass cloth or paper base materials and epoxy resins, phenolic resins, or unsaturated polyester resins have been used for printed wiring boards and insulating boards for industrial and consumer electronic devices. has been used.

In recent years, the miniaturization and weight reduction of electronic devices has required higher density, finer, thinner printed wiring boards, and multilayer circuits. There is a demand for materials with small dimensional changes even under humid conditions.

However, conventional paper-based unsaturated polyester resin copper-clad laminates and laminates have low mechanical strength and lack dimensional stability during soldering during processing and component mounting.
However, there were drawbacks such as the tendency for twisting to occur.

The present invention solves the above-mentioned drawbacks, and provides a laminate in which the base material is impregnated with an unsaturated polyester resin and laminated and heat-molded.
Weight% mixed cellulose fiber base paper, especially density 0.3~
Mouse is 0.6, wet tensile strength is 03-3.0 kg/i
The shrinkage rate by heating at 150℃ for 2 hours for 2 hours is 0.4 inches or less,
It is characterized by using the above-mentioned glass fiber mixed cellulose fiber base paper which has a swelling rate of 0.2 inches or less when subjected to humidification treatment at 40° C. relative humidity 90% for 96 hours.It has excellent mechanical strength and is subjected to heating and humidification treatment. This relates to a laminate with small dimensional changes over time, and the glass fiber to be mixed is E-glass for electrical use, #11! A defibrated filament with a fiber diameter of 6 to 13 μm and a length of 3 to 20 fibers is suitable, and as the cellulose fiber, kraft pulp fiber made from hardwood is suitable. That is, for example, in the process of making kraft base paper for laminate boards using kraft pulp fiber as a raw material, it is characterized by using a mixed paper obtained by homogeneously dispersing and defibrating specific glass fibers. However, when it comes to papermaking, no special binder is needed, and the glass fibers are well mixed with #1 in the gaps between the base paper fiber micelles, creating a strong and rigid network structure. It has been found that it is possible to significantly suppress dimensional changes compared to fiber base paper.

More specifically, it has become clear that a mixed paper in which the content of glass fibers relative to kraft pulp fibers is in the range of 3 to 25% by weight, particularly 5 to 20% by weight, is preferable. 3
If the weight is less than -, the effect of improving the dimensional stability of glass fiber is insufficient, and if it is more than 20% by weight, it is effective in improving the mechanical strength, but in terms of dimensional stability, heating shrinkage and humidification swelling are Even if the number of glass fibers is increased, it will not have any effect, and in terms of punching workability, a portion of the glass fibers will not be cut sufficiently around the punching hole, which is undesirable.

Next, the selection of glass fibers to be mixed is determined based on the mixing ratio as well as electrical properties, dimensional stability, strength, processability, and productivity of the base paper.
This is an important factor for economical efficiency, and from the viewpoint of mixing paper with cellulose fibers, E-Garako - fiber diameter 6 to 13 μm, fiber length 3
~20 ■ is suitable.

Furthermore, the glass fiber mixed paper obtained in the above manner effectively suppresses the dimensional change of the laminate under heating and humidification treatment, so that the heating shrinkage after heating at 150°C for 2 hours is 0.
．． 4% or less, and the paper must be made uniform so that the humidified swelling rate after processing at 40°C and 90% humidity for 96 hours is 0.2 inches or less. In order to reduce the dimensional change after heating and humidification treatment in this way, mixing paper with glass fiber is effective and is necessary to economically obtain a laminate with small dimensional change.

Density as a base paper is an important factor for impregnating a resin face, but by mixing glass fiber, a low density base paper with good impregnation properties can be obtained.
A range of 6 f/cd is suitable.

The wet tensile strength of the base paper relates to the strength of the resin face when it is impregnated, and a certain level of strength is required to avoid problems such as base paper breakage during the process in the production equipment. In particular, unsaturated polyester has a wet tensile strength of 0.3 to 3.
Relatively large strength of 0 kg/15+++m is required. If it is less than 0.3 kf/15 mm, water will cause the base paper to break up, making it difficult to use in mass production.

This strong base paper with a wet tensile strength of 0.3 to 3.0 kg/15 is composed of so-called wet paper strength enhancers such as urea/formaldehyde resin, polyethyleneimine, melamine/formaldehyde resin, polyamide/polyamine/epichlorohydrin resin, polyamide It is obtained by improving the wet tensile strength by treating it with a water-soluble thermosetting resin such as acrylamide that crosslinks when heated. Of course, it is also possible to add an inorganic substance such as antimony trioxide to impart flame resistance to this mixed paper.

The unsaturated polyester resin used in the present invention is, for example, what is generally called an orthophthalic acid type, an isophthalic acid type, a bisphenol type, a vinyl ester type, or a modified version of these. This unsaturated polynisder resin contains antimony trioxide, calcium carbonate, clay,
It is acceptable to add inorganic substances such as silica, as well as coupling agents and the like to increase affinity with inorganic substances. The obtained laminate has excellent mechanical strength, and dimensional changes in the vertical, horizontal, and thickness directions are small even under temperature and humidity conditions.
It is possible to obtain a plate with less occurrence of warping and twisting, having the necessary strength even with a thin plate, and having good low-temperature punching workability.

Of course, in this case, it goes without saying that the present invention also includes single-sided or double-sided copper-clad laminates obtained by overlapping copper foils during lamination molding.

As described above, by carrying out the method of the present invention, it is possible to produce laminated root cuttings with small dimensional changes under heating and erosion conditions, less warping and twisting after heating and heating, and excellent mechanical strength. copper-clad laminates can be obtained economically.

The present invention will be explained below with reference to Examples.

Example Kraft paper with different glass fiber mixing ratio and wet tensile strength as shown in Table 741 was impregnated with water-soluble methylolmelamine resin to a resin content of 10%, and then impregnated with isophthalic acid polyester resin. A laminated plate having a resin content of 55% and a thickness of 1.6 van was obtained by lamination and heat molding. The bending strength, heating shrinkage rate, humidification swelling rate, anti-υ property, punching workability, and workability of these laminates are shown in Table 1. 1st
As is clear from the table, the laminates obtained in each example showed small dimensional changes under heating and humidification conditions, small warpage after heating, and other excellent properties.

(Note 1) The initial dimension is LO, the dimension without heat treatment at 150° C. for 2 hours is Ll, and the heat shrinkage rate was calculated using the following formula.

Heat shrinkage rate (%) = Lo −L+ / Lo X 1
00 (Note 2) The initial dimension is tol and the dimension after 96 hours of treatment at 40°C and relative humidity of 90°C is tl, and the humidification expansion rate was calculated using the following formula.

Humidification swelling rate (%) -1! -io / to X 10
0 (Note 3) A sample of 420×330wn was treated at 220° C. for 10 minutes (−1), then placed flat on a surface plate, and the maximum lifting amount was measured.

(Note 4) Based on JISK-6911.

Claims (1)

[Scope of Claims] 1. An unsaturated polyester resin laminate, characterized in that it is obtained by impregnating cellulose fiber base paper mixed with 3 to 25% by weight of glass fiber back with an unsaturated polyester resin, and then laminating and heat-molding it. Board. 2. The density of the fiberglass base paper mixed with glass fiber is 03 to 0.
69Atd, wet tensile strength 03-3.0 kg715
Feature V characterized by having a shrinkage rate of less than 0.4% when heated at 150°C for 2 hours and an expansion rate of less than 0.02% when humidified at 40°C and relative humidity of 90°C for 96 hours [Claim 1 Laminated board as described. 3. The glass fiber to be mixed is E-glass for electrical use, and its fiber diameter is 6 to 13 μm, and the length is 3 to 20 WIWl. 4. A patent in which the cellulose fiber base paper is kraft pulp fiber made from hardwood pulp. A laminate according to claim 1 or claim 2.