JPH0715103A - Manufacture of one-side copper-clad laminate - Google Patents

Abstract

PURPOSE:To make a laminate with a small warp by increasing the quantity of resin for a prepreg in contact with a mold-releasing film by a specified quantity as compared with the quantity of resin for a prepreg in contact with a copper foil for formation of a circuit. CONSTITUTION:A copper foil 1 for formation of a circuit is arranged on the outside of the outermost prepreg 4 among plural sheets of prepregs 4 stacked, and a mold- releasing film 2, on the outside of the other outermost prepreg, and those are molded by heating, and then the mold-releasing film 2 is exfoliated. In case of manufacturing a laminate whose one side is clad with copper this way, the quantity of resin of the prepreg 4b in contact with the copper foil 1 for circuit formation is increased by 10wt.% or more as compared with the quantity of resin as compared with the quantity of resin of the prepreg 4a in contact with the copper foil 1 for circuit formation. For example, those are stacked in the order of two sheets of prepreg 4b of 50% in quantity of resin in contact with the face of the mold releasing film 2, two sheets of prepreg 4a of 40% in quantity of resin, and the copper foil, and the laminate is put between molding plates, and then it is heated for six minutes at 170 deg.C in temperature and 40kg/cm<2> in pressure, and then the mold-releasing film 2 is exfoliated to get a laminate whose one side is lined with copper.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a single-sided copper-clad laminate, and more particularly to a method for producing a single-sided copper-clad laminate for printed wiring boards used in electronic equipment and electric equipment.

[0002]

2. Description of the Related Art In the production of a single-sided copper-clad laminate, for example, a base material is impregnated with an epoxy resin and a plurality of semi-cured prepregs are stacked, and a copper foil is placed on the outermost prepreg outer surface of these prepregs. On the other outermost prepreg outer surface, a release film such as a triacetate film that can be released from the molding plate is laminated, and the laminated body is sandwiched between the molding plates and heated and pressed to mold. The single-sided copper-clad laminate thus obtained has a warp that is concave toward the copper foil surface side after the completion of molding. It is speculated that the above-mentioned warpage occurs because the expansion and contraction behavior due to heat of the copper foil and the release film disposed on both sides of the prepreg differ greatly. However, there is a problem in that the dimensional accuracy is insufficient during punching and printing.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a method for manufacturing a single-sided copper-clad laminate having a small warpage.

[0004]

A method for manufacturing a single-sided copper-clad laminate according to the present invention comprises a method of separating a copper foil for forming a circuit on the outermost prepreg outer surface of a plurality of prepregs stacked on the other outermost prepreg outer surface. In the method for producing a single-sided copper-clad laminate in which a mold film is provided and heat-molded, and then the mold release film is peeled off, the resin amount of the prepreg in contact with the mold release film by the prepreg is the copper foil for forming the circuit. It is characterized in that it is 10% by weight or more as compared with the resin amount of the prepreg in contact with.

[0005]

According to the method for producing a single-sided copper-clad laminate of the present invention, a copper foil for forming a circuit is provided on the outermost prepreg outer surface of a plurality of prepregs and a release film is provided on the outermost prepreg outer surface. After heat-molding, in the method for producing a single-sided copper-clad laminate for peeling the release film, the resin amount of the prepreg in contact with the release film in the prepreg is the resin of the prepreg in contact with the copper foil for circuit formation. Since the amount is 10% by weight or more in comparison with the amount, the shrinkage of the laminate due to heating and cooling increases as the amount of resin increases.
It functions to make the warpage of the laminated plate convex toward the copper foil surface side, thus reducing the warpage.

The present invention will be described below with reference to the drawings. FIG. 1 is a sectional view in which constituent materials of a single-sided copper-clad laminate according to an embodiment of the present invention are shown separately.

The method for producing a single-sided copper-clad laminate according to the present invention comprises:
As shown in FIG. 1, several prepregs (4) in which a base material is impregnated with resin are stacked, a copper foil (1) is placed on the outer surface of the outermost prepreg (4), and another outermost prepreg (4). Molding plate and release film on outer surface of (4) (2)
Are arranged and laminated. The laminated body is sandwiched between molding plates, and the resin in the substrate is cured by heating and pressing.

Examples of the resin include epoxy resin,
Examples include polyimide. Examples of the base material include woven fabrics, non-woven fabrics, mats or papers composed of inorganic fibers such as glass and asbestos, organic synthetic fibers such as polyester, polyamide, polyvinyl alcohol and acrylic, and natural fibers such as cotton, or a combination thereof. Wood is used.

Examples of the release film (2) include resin films such as triacetate, fluorine resin, polypropylene, polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and the temperature for heat-molding a single-sided copper-clad laminate. It is appropriately selected according to the above. Further, in the present invention, the copper foil (1) for forming a circuit, which is provided on one surface of the prepreg, is not particularly limited.

The configuration of one embodiment of the present invention is shown in FIG. Among the prepregs (4) used for the above-mentioned single-sided copper-clad laminate, the resin amount of the prepreg (4a) in contact with the release film (2) is larger than that of the prepreg (4b) in contact with the copper foil (1) for circuit formation. There is a large amount, and the difference between these resin amounts is 10
It is configured to be more than weight% (hereinafter referred to as%).
When two or more prepregs (4) are used, the resin amount of the prepreg (4) sandwiched between the prepreg (4a) in contact with the release film (2) and the prepreg (4b) in contact with the copper foil (1) is , Both prepregs (4a), (4b)
Or both prepregs (4a),
The amount of resin between (4b) may be used and is not particularly limited. Since shrinkage of the laminated plate due to heating and cooling increases as the amount of resin increases, it functions to make the warp of the laminated plate convex toward the copper foil surface side, and thus reduces the warp.

After taking out the laminate obtained by curing the resin in the base material by the above heating and pressing from the molding plate, the release film (2) is peeled off to obtain a single-sided copper-clad laminate.

[0012]

EXAMPLE 1 FIG. 1 shows the structure of a single-sided copper-clad laminate according to Example 1.
A 15 μm polypropylene film was used as the release film (2), and a 35 μm-thick foil (trade name TSTO manufactured by Furukawa Circuit Foil Co., Ltd.) was used as the copper foil (1) for forming a circuit. As prepreg (4),
180 μm thick glass cloth (Nittobo, trade name WE
A prepreg (4a) having a resin content of 40% and a prepreg (4b) having a resin content of 50%, which were obtained by impregnating -116) with an epoxy resin and semi-cured, were used.

Two prepregs (4b) having a resin content of 50%, two prepregs (4a) having a resin content of 40%, and a copper foil (1) are laminated in this order on the surface of the release film (2), and this lamination is performed. The plate body is sandwiched between molding plates, and the temperature is 170 ° C and the pressure is 4
After heating at 0 kg / cm ² for 60 minutes, the release film (2) was peeled off to obtain a single-sided copper-clad laminate.

Comparative Example 1 The structure of a single-sided copper-clad laminate according to Comparative Example 1 is shown in FIG.
Instead of the prepreg (4) of Example 1, a thickness of 180 μm
Glass cloth (product name: WE-116, manufactured by Nitto Boseki Co., Inc.) was impregnated with an epoxy resin and semi-cured. A resin amount of 45% was used as a prepreg (4).

Four prepregs (4) in contact with the surface of the release film (2) and a copper foil (1) are laminated in this order, the laminated plate body is sandwiched between molding plates, and the temperature is 170 ° C. and the pressure is 40 k.
After heating at g / cm ² for 60 minutes, the release film (2) was peeled off to obtain a single-sided copper-clad laminate.

The warpage of the obtained single-sided copper-clad laminate was evaluated.
Place a single-sided copper-clad laminate cut into a vertical size of 500 mm x width of 500 mm on a smooth surface plate and set the maximum lifting amount to JIS.
It was measured with a first-class gold scale.

The results of the warpage measured as described above are shown in Table 1. For the sled, a sled that is concave on the copper foil surface side is shown as minus, and a sled that is convex on the copper foil surface side is shown as plus. Both Example 1 and Comparative Example 1 had a positive warpage, and Example 1 had a better warpage after etching than Comparative Example 1.

[0018]

[Table 1]

[0019]

According to the method for producing a single-sided copper-clad laminate of the present invention, a single-sided copper-clad laminate with a small warpage can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing separated constituent materials of a single-sided copper-clad laminate according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing separated constituent materials of a single-sided copper-clad laminate according to a comparative example of the present invention.

[Explanation of symbols]

 1 Copper foil 2 Release film 4 Prepreg 4a Prepreg 4b Prepreg

Claims (1)

[Claims] 1. A copper foil for forming a circuit is provided on the outermost prepreg outer surface of a plurality of prepregs, and a release film is provided on the other outermost prepreg outer surface, and the release film is heat-molded. In the method for producing a single-sided copper-clad laminate to be peeled off, the resin amount of the prepreg in contact with the release film by the prepreg is 10% by weight or more as compared with the resin amount of the prepreg in contact with the circuit-forming copper foil. A method for producing a single-sided copper-clad laminate characterized by the above.