JPS5942628B2 - Manufacturing method for copper clad laminates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a copper fabric having a structure in which a glass woven fabric substrate impregnated with a thermosetting resin is laminated on both surfaces of a glass nonwoven substrate layer impregnated with a thermosetting resin, and then a copper foil is placed on the substrate. This invention relates to a method for manufacturing stretched laminates.

In recent years, a thermosetting resin-impregnated glass nonwoven fabric base material layer is used as the core, and thermosetting resin impregnated glass woven fabric base materials are layered on both surfaces to improve the punching strength of the nonwoven fabric base material layer, as well as improve electrical properties and strength. A so-called thermosetting resin-impregnated glass nonwoven fabric core-glass woven fabric surface copper-clad laminate is on the market, which attempts to provide the supplementary effect of this with a glass woven fabric base material layer.

However, the conventional copper-clad laminate has the following drawbacks. (1) During punching, separation easily occurs between the glass nonwoven fabric base layer and the glass woven fabric base layer.

This is because the glass woven fabric base material layer, which is a reinforcing material, has high shear resistance during punching. Also, the finish of the punched hole
This was not very good and caused problems during the printed circuit board manufacturing process, resulting in lower yields and problems when inserting components into the punched holes. (2) Interlayer hair cracks (thin cracks) are likely to occur between the glass nonwoven fabric base material layer and the glass woven fabric base material layer due to heat treatment during the printed circuit board manufacturing process and component attachment, reducing the reliability of the board. Inferior.

(3) As a method to solve these problems, it is possible to plasticize the impregnated thermosetting resin to improve punching workability, but this reduces heat resistance and increases dimensional changes and rebound. Due to the above-mentioned drawbacks, the actual situation is that the use of substrates that are subject to thermal shock, such as printed resistor applications and chip bonding applications, which have recently been remarkable, is limited.

The present invention eliminates the above-mentioned drawbacks, has excellent punching workability, has little delamination during punching and less occurrence of interlayer hair cracks during heat treatment, and is impregnated with a thermosetting resin that maintains sufficient electrical properties and has little warping. The object of the present invention is to provide a glass nonwoven core-glass woven surface copper-clad laminate.

In order to achieve the above object, the present invention provides a glass woven fabric substrate impregnated with a thermosetting resin on both surfaces of a glass nonwoven fabric base laminated material layer 1 impregnated with a thermosetting resin as shown in the drawings. In the production of a laminate in which the laminate materials 2 are stacked and the copper foil 3 is placed on the outermost surface of at least one side, the thermosetting resin to be impregnated into the glass woven base material is added per 100 parts of the thermosetting resin. In some cases, 5 to 20 parts of inorganic silicate hollow fine powder (microspheres) are contained.

When the glass woven base laminated material 2 containing inorganic silicate hollow powder is used for the surface layer, the surface glass woven base material is It reduces the shear resistance during layer punching and improves punching workability. It also reduces interlayer hair cracks by reducing thermal shock during heat treatment in the printed circuit board manufacturing process, and also suppresses expansion and contraction of the resin to improve resistance. It has become possible to reduce the amount of corrosion and dimensional changes. In carrying out the present invention,
As the thermosetting resin to be impregnated into the glass nonwoven fabric base material, bisphenol A type epoxy resin, tetrapromobis J
G-Nol A type epoxy resin, phenol- or alkyd-modified epoxy resin, polyester resin, etc. The above-mentioned thermosetting resin can also be used as a thermosetting resin to be impregnated into the glass woven substrate for the surface. (preferably from the viewpoint of increasing interlayer adhesion) The same resin is preferably used to impregnate the glass nonwoven fabric substrate and the glass woven fabric substrate.

As the glass nonwoven fabric, there may be used a fabric made from short glass fibers using a synthetic resin as a binder, a glass nonwoven fabric made by mixing bulp or organic fibers, a glass mat made by intertwining long glass fibers, and the like. Hollow fine powder of inorganic silicate is
A hollow fine powder having a particle size of 200 μm or less and a particle density of 1.0 g/~ or less, preferably having a closed cell structure, can be used.

If the particle density exceeds 1.0 g/d, the effect of reducing the density is small and the shear resistance cannot be sufficiently reduced.
In addition, the thermal conductivity increases, and the buffering effect against thermal shock is insufficient, so that the purpose cannot be achieved. Further, a closed cell structure is preferable in view of the above-mentioned decrease in thermal conductivity. For example, silicon oxide powder (density 2.5 g/CTil), talc (density 2.7
g/Crlt) etc. will not produce the desired effect. When incorporating the above-mentioned hollow fine powder into a thermosetting resin, from the viewpoint of uniform dispersion and stability of the varnish, the particle size is 2.
It is preferable to knead the hollow fine powder of 00μ or less, preferably 75μ or less with a small amount of thermosetting resin varnish in advance.

At this time, if a silane coupling agent containing an epoxy group is added, the electrical properties of the laminate can be further improved. The higher the amount of the hollow fine powder added, the lower the density and the more effective the prevention of interlayer hair cracks caused by thermal shock, but the dispersibility into thermosetting resin varnish and the moldability during heating and pressing may be affected. Due to the above considerations, there is an upper limit to the amount used, and it is preferable to mix 5 to 20 parts with respect to 100 parts of the thermosetting resin, and if it is less than 5 parts, the desired effect cannot be expected.

A glass woven fabric base material, such as a commercially available plain weave glass woven fabric, is impregnated with a thermosetting resin varnish containing the hollow fine powder of inorganic silicate prepared in this manner to obtain a glass woven fabric base material laminate material 2, This is layered on both surfaces of the glass woven fabric base material laminate layer 1 impregnated with the thermosetting resin varnish to which no hollow fine powder is added. The number of layers of the glass nonwoven fabric base laminate material 1 varies depending on the required thickness of the laminate, but the number of layers of the glass woven fabric base laminate material 2 on the surface is preferably 1 to 2. If the number exceeds 2, the punching processability will deteriorate.

On the other hand, if a thermosetting resin varnish to which the hollow fine powder is added is used in the glass nonwoven fabric laminate material layer 1, the density of the entire laminate decreases, making it difficult to obtain a laminate that maintains the required mechanical strength. Next, by overlapping the copper foil 3 on at least one surface of the glass woven fabric base material laminate VJi2 and applying heat and pressure, the intended copper-clad laminate can be obtained. Example A glass nonwoven fabric made from short glass fibers using a synthetic resin as a binder is treated in advance with a phenolic resin initial condensate and an aminosilane compound.

An epoxy resin varnish for impregnation (hereinafter referred to as varnish A) having a concentration of 5070 is prepared by dissolving a bisphenol A type epoxy resin in a mixed solvent of methyl cellosol acetone together with a curing agent dicyandiamide and an accelerator benzyl dimethylamine. The above-treated glass nonwoven fabric was impregnated and dried to obtain an epoxy resin-impregnated glass nonwoven fabric base laminate material. On the other hand, the average particle size was 75μ so that the blending ratio was 10 parts to 100 parts of the solid content of the varnish A.
, particle density 0.2g/CT! A hollow fine powder of an inorganic silicate having a closed cell structure of t is weighed, and after kneading the hollow fine powder with 1/5 of the required amount of varnish A in a ball mill, 1 is left in the kneaded product.
) 4/5 of the above Varnish A and a silane coupling agent (170 added to Varnish A) were mixed to obtain an epoxy resin varnish containing hollow fine powder of inorganic silicate (hereinafter referred to as Varnish B). . Glass woven fabric base material impregnated with epoxy resin containing hollow fine powder of inorganic silicate by impregnating a glass woven fabric with a thickness of 0.1 m/m with the varnish B to a resin content of 4570 and drying. A laminated material was obtained. Next, 12 sheets of the epoxy resin-impregnated glass non-woven base laminated material are stacked to form a core layer, and epoxy resin-impregnated glass woven base laminated material strips containing the hollow fine powder are placed on both surfaces of the core layer. Stack one sheet, place a 35μ thick copper foil on the outermost surface of one, insert it into a press, and press at a temperature of 160℃ and a pressure of 70K9/Cr.
Molded under heat and pressure for 60 minutes to a thickness of 1.6m.
/m copper-clad laminate was obtained.

The properties of the copper-clad laminate are shown in Tables 1 and 2. Comparative Example An epoxy resin-impregnated glass nonwoven fabric base laminate material was prepared in the same manner as in the previous example.

On the other hand, 170% of a silane coupling agent was added to varnish A in the above example (no hollow fine powder of inorganic silicate was added), and the resulting varnish was applied to a glass woven fabric with a thickness of 0.1~. The mixture was impregnated to a resin amount of 4570% and dried to obtain an epoxy resin-impregnated glass woven fabric base laminate material phase. Next, 12 sheets of the above-mentioned epoxy resin-impregnated glass non-woven fabric base laminated material are stacked to form a core layer, and one sheet each of the epoxy resin-impregnated and glass woven base laminated materials are stacked on both surfaces of the core layer, and the outermost surface of this one is stacked. A copper foil with a thickness of 35 μm was placed on the plate and inserted into a press, and heated and pressed under the same conditions as in the example to obtain a copper-clad laminate with a thickness of 1.6 μm or more. The properties of the copper-clad laminate are shown in Tables 1 and 2. 1st
As is clear from Table 2, the shear resistance of the copper-clad laminates obtained in the examples was reduced during punching compared to the comparison example in which hollow fine powder of inorganic silicate was not added. , delamination (interlayer hair cracks due to substrate thermal shock during punching) does not occur even after 10 cycles of thermal shock, and can withstand thermal shock during printed circuit manufacturing or soldering.Also, electrical properties. The reduction of the soil and anti-b is also the filling effect of the hollow fine powder.As mentioned above, the thermosetting resin-impregnated glass woven fabric base material containing the hollow fine powder of inorganic silicate is used as the glass non-woven fabric base material layer. By using it on both surfaces, it is possible to obtain a highly reliable copper-clad laminate that improves punching workability and has fewer interlayer hair cracks caused by heat during printed circuit board manufacturing. They can be used for resistors and chip bonding, and each has great industrial value.

[Brief explanation of drawings]

The drawing is an explanatory cross-sectional view showing the laminated structure of a copper-clad laminate according to the method of the present invention. DESCRIPTION OF SYMBOLS 1... Glass nonwoven fabric base material laminated material layer, 2... Glass woven fabric base material laminated material phase layer, 3... Copper foil.

Claims (1)

[Claims] 1 Layer the glass woven base laminated material layer impregnated with a thermosetting resin on both surfaces of the glass nonwoven base laminated material layer impregnated with a thermosetting resin, and place a copper foil on at least one outermost surface. In a method for manufacturing copper-clad laminates that involves heating and pressing, the thermosetting resin impregnated into the glass woven substrate contains 5 to 20 parts of inorganic silicate hollow fine powder per 100 parts of the thermosetting resin. A method for manufacturing a copper-clad laminate, characterized by containing.