JPH04323012A - Manufacture of laminated sheet - Google Patents

Abstract

PURPOSE:To make the manufacturing of laminated sheet with no development of smears possible by a method wherein laminate in continuous form, which is produced by arranging metal foil in continuous form on the surface of the predetermined number of sheets of phenolic resin impregnated base material in continuous form, is formed under heat and pressure and, after being cut in lengths, reheated and quenched. CONSTITUTION:Laminate is produced by arranging metal foil in continuous form 2 to the top surface and/or rear surface of the predetermined number of sheets of resin-impregnated base material in continuous form 1 such as glass sheet or the like impregnated with the predetermined phenolic resin so as to press the laminate 3 with a double belt former 4 by the pressure of 1-50kg/cm<2> and at the temperature of 140-180 deg.C. Next, laminated sheet after being treated under heat and pressure is cut in lengths with a cutter 9 and reheated in an heating oven 8 and finally quenched. The re-heat-treating is to suppress the development of the warpage and normally performed at 100-150 deg.C for 20-60min. Thus, laminated sheet having favorable heat resistance is produced highly efficiently with no development of smears.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method for manufacturing a laminate. More specifically, the present invention is capable of producing a smear-free printed wiring board laminate useful for electrical/electronic equipment, communication equipment, computers, etc. with high thickness accuracy and suppressing warping. It concerns a new continuous manufacturing method.

0002

[Prior Art] Conventionally, electrical/electronic equipment, communication equipment,
Printed wiring boards having various configurations have been used in computers and the like. Regarding these printed wiring boards,
In response to the increasing demand for high-density packaging in recent years, there has been a strong demand for improvements in the heat resistance and dimensional accuracy of laminates as base materials.

[0003] In response to such demands for improved technology, various improvements have been made to the composition of the resin, additives, etc. of the laminate. At present, laminates made of epoxy resin-impregnated base materials are generally widely used as heat-resistant electrical laminates.

0004

[Problems to be Solved by the Invention] However, despite the various efforts and improvements that have been made so far, laminates using conventional epoxy resins are useful as general-purpose heat-resistant electrical laminates, but they still suffer from smearing. Moreover, in the case of the conventional press production method as a conventional method for forming laminates, the drawback of low thickness accuracy was unavoidable.

[0005] Therefore, it has been desired to realize a new method for manufacturing a laminate that is less expensive, has good heat resistance, is free from smearing, and has excellent thickness accuracy. This invention has been made in view of the above circumstances, and aims to eliminate the drawbacks of conventional epoxy resin laminates and to produce heat-resistant laminates that do not cause smearing and have good thickness dimensional accuracy. The purpose is to provide a method.

[0006]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a long laminated structure in which a required number of long base materials impregnated with phenolic resin are provided with long metal foils on the upper and/or lower surfaces. The body is continuously heated and pressure molded using a double belt molding machine, cut into the required dimensions, and then reheated.
Provided is a method for manufacturing a laminate, which is characterized in that the method is then subjected to a rapid cooling treatment.

[0007] In the manufacturing method of the present invention, the long base material impregnated with a phenolic resin as described above is used as the base material, but as the phenol resin in this case, various known ones can be used. For example, any one of novolak type phenol resin and resol type phenol resin can be used. More preferably, resol type phenolic resins are used,
Furthermore, this phenol resin may be modified with melamine or epoxy.

These phenolic resins may be treated with water, a diluent such as acetone, an inorganic filler, a viscosity modifier,
Furthermore, it can be impregnated into a base material as a solution or varnish containing a flame retardant or the like. As the base material for this purpose, that is, the elongated base material in the present invention, glass fibers, synthetic fiber woven fabrics, nonwoven fabrics, paper, other general papers, etc. can be used.

[0009] Metal foils for integral molding in a double belt molding machine include copper, aluminum, iron, nickel, and the like, which have been conventionally used for printed wiring boards.
It is a foil body made of metal such as zinc or an alloy, and if necessary, an adhesive layer may be provided on one side for molding. For hot-pressure molding using a double belt molding machine, for example, as illustrated in FIG. 1, a predetermined number of upper surfaces and/or Alternatively, a long metal foil (2) is arranged on the bottom surface to form a laminate, and this long laminate (3
) is heated and pressurized using a double belt molding machine (4). This molding is generally performed under conditions of a pressure of 1 to 50 kg/cm2 and a temperature of 140 to 180°C.
This can be done in about 0 minutes.

[0010] In this molding, an adhesive layer (21) may be provided on the metal foil (2) in advance. The arrangement, size, etc. of the presser roller (5), the roller (6) of the double belt molding machine (4), etc. can be made as appropriate. The laminate plate formed under heat and pressure is cut into a predetermined size using a cutter (7) as illustrated in FIG.
) and then rapidly cooled in a cooling tank (9). This reheating treatment is to suppress the occurrence of warping of the laminate, and is usually heated to a temperature of 100 to 150°.
Preferably, the treatment is carried out at a temperature of C for 20 to 60 minutes.

[0011] The quenching treatment is not limited to the example shown in FIG. 1, but can be performed by water cooling, cold solvent, cold air, or the like, which aims to further improve this warpage. Among these, water cooling with a large capacity is more preferable. The temperature at this time is, for example, -10 to +25°C
It can be done to a certain extent. In this way, a phenolic resin metal-clad laminate (10) of a predetermined size is obtained.

[0012] It goes without saying that various embodiments are possible in terms of detailed configuration.

[0013]

[Operation] In this invention, since the long base material impregnated with phenolic resin is continuously molded, smear does not occur because the heat deformation temperature of the phenol resin is essentially high. Compared to the conventional method, which employs a multi-stage press forming method with about 15 sheets per stage and 20 to 30 stages, the thickness accuracy can be adjusted one sheet at a time.

[0014] Therefore, it is possible to produce laminates having good heat resistance with high efficiency and high dimensional accuracy without the occurrence of smearing. Further, in the present invention, by performing reheating and rapid cooling treatment, warping of the manufactured laminate can be more effectively suppressed.

[0015]

【Example】

Example 1 A laminate was manufactured using the double belt molding machine shown in FIG. At that time, each of three long glass cloths with a width of 105 cm and a thickness of 0.15 mm was impregnated with a 50% by weight methyl alcohol solution of resol-type phenolic resin, and then the top and bottom surfaces of the dried prepreg were coated with a 0.15 mm thick glass cloth. A long laminate in which adhesive-coated copper foils of 0.035 mm were stacked was used.

[0016] Molding with a double belt molding machine is 30 kg.
The molding was carried out by heating and pressing at a molding pressure of /cm2 and a temperature of 160°C for 10 minutes. After that, cut it to 100cm using a cutter.
Each piece was cut to obtain a laminate with a thickness of 0.6 mm. After heating this again at a temperature of 120 °C for 60 minutes,
It was quenched in water at °C.

This laminate was evaluated for smearing caused by drilling, dimensional accuracy, and warping. As shown in Table 1, no smear occurred, and
The thickness dimensional accuracy and warpage suppressing effect were also excellent. Example 2 A laminate was manufactured in the same manner as in Example 1 using a novolac type phenolic resin. The performance evaluation was also good as shown in Table 1.

Comparative Example 1 A glass cloth measuring 105 x 105 cm and having a thickness of 0.15 mm was impregnated with a 45% by weight solution of epoxy resin in methyloxytol and dried to obtain a prepreg. The same copper foil as in Example 1 was layered on top and bottom of this prepreg to a thickness of 1 m.
sandwiched between slanless plates of m, and inserted 15 sets into the stage.
30 stage press, molding pressure 35Kg/cm2, temperature 17
Heat and pressure molding was performed at 0°C for 120 minutes. As a result, a laminate with a thickness of 0.6 mm was obtained.

The performance of this product was also evaluated, and the results shown in Table 1 were obtained. Smearing occurred and the accuracy of the thickness dimension was not good. Cooling implementation 2 A laminate was manufactured in the same manner as in Example 1 except that quenching was not performed,
Performance was evaluated. As shown in Table 1, the effect of suppressing warpage was not sufficient.

[0020]

[Table 1]

[0021]

According to the present invention, as explained in detail above, a heat-resistant laminate without smearing can be produced with good thickness accuracy and warpage control.

[Brief explanation of drawings]

FIG. 1 is a process sectional view illustrating the manufacturing method of the present invention.

[Explanation of symbols]

1 Phenolic resin impregnated long base material 2 Long metal foil 3 Long laminate 4 Double belt forming machine 5 Presser roller 6 Roller 7 Cutter 8 Heating furnace 9 Cooling tank

Claims (1)

[Claims] [Claim 1] A long laminate having a required number of phenolic resin-impregnated long substrates with long metal foils disposed on the upper and/or lower surfaces is continuously heated and pressure molded using a double belt molding machine to form the required number of long substrates. A method for manufacturing a laminate, which comprises cutting the laminate into dimensions, reheating it, and then rapidly cooling it.