JP3352034B2 - Prepreg and laminate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a prepreg for manufacturing a metal foil-clad laminate and a laminate manufactured by using the prepreg, and particularly to a semiconductor package or the like which is required to have high electrical characteristics and high plate thickness accuracy. The present invention relates to a prepreg and a laminate that can be used in the field.

[0002]

2. Description of the Related Art A metal foil-clad laminate used for processing into a printed wiring board is formed by laminating a metal foil such as a copper foil on one or both outer surfaces of a prepreg, and molding by heating and pressing. It is manufactured by. Here, when performing the heating and pressing, the combined material in which the prepreg and the metal foil are overlapped is stacked in multiple stages via a mirror surface plate, and this is set between the hot plates, pressed with the hot plate and heated. Do
It was common to use a so-called multi-stage hot press method.

[0003] However, in a multi-stage hot press using such a hot plate, a combination material arranged at a position close to the hot plate and
Since the conduction speed of heat conducted from the hot plate differs from that of the combination material located far from the hot platen, the heating temperature becomes uneven, and the resin contained in the prepreg of each combination material during heating and pressing Of the resin flow, and variations in quality such as the thickness of the sheet occur. Also, if the melt viscosity of the resin in the prepreg is increased to prevent the resin flow and improve the plate thickness accuracy, there is a problem that unevenness in the heating temperature causes a defective spot.

Therefore, a method of connecting a power supply to the metal foil and causing the metal foil to generate heat to perform heating has been proposed.
It is provided, for example, in Japanese Patent Publication No. 7-508940. FIG. 1 shows an example of such a prepreg, in which two long metal foils 2 are used, and a plurality of prepregs 1 are sandwiched between the two metal foils 2 to form a prepreg. 1 and a combination material 3 including upper and lower metal foils 2 are formed. The metal foil 2 is bent in a meandering manner while forming a plurality of sets of the combination members 3 in the longitudinal direction of the metal foil 2, and the plurality of combination members 3 are stacked in multiple stages via an insulating mirror plate 4. When this is set between the pressure plates 5, the metal foil 2 generates heat by Joule heat, and the heat can heat each combination material 3 to perform molding.

According to this method, the prepreg 1 of each combination 3 can be directly heated using the metal foil 2 as a heat source, so that the prepreg 1 of each combination 3 stacked in multiple stages can be uniformly heated. It is possible to obtain a metal foil-clad laminate by multi-stage molding without variation in quality.

[0006]

In the above-mentioned conventional method using a multi-stage hot press, the heating temperature of the prepreg of each combination material becomes non-uniform. A prepreg designed to be small is used. However, in the method of heating by energizing the metal foil to generate heat, the heating temperature of the prepreg of each combination material becomes uniform, so if the prepreg conventionally used is used as it is, the flow of the resin is rather reduced. It became large and the plate thickness accuracy deteriorated. An epoxy resin prepreg for solving such a problem is disclosed in Japanese Patent Application Laid-Open No. 9-23899.
No. 8 discloses a laminate manufactured using such a prepreg, which has a high dielectric constant and a large dielectric loss tangent. It could not be used in the fields considered to be.

The present invention has been made in view of the above points, and is prepared by using a modified polyphenylene ether. It is an object of the present invention to provide a prepreg capable of producing a metal foil-clad laminate by a method of heating by generating heat, and a laminate produced by the prepreg.

[0008]

According to a first aspect of the present invention, there is provided a prepreg according to the first aspect of the present invention, in which the metal foil 2 laminated on the prepreg 1 is energized to generate heat.
In the prepreg 1 used for manufacturing a laminate by curing the resin component of, a polyphenylene ether,
It is obtained by impregnating and drying a base material with a resin varnish containing an epoxy resin and a curing agent, and has a melt viscosity at 170 ° C. of 5,000 to 50,000 poise at 170 ° C.

A prepreg according to a second aspect of the present invention, in addition to the constitution of the first aspect, further comprises:
The titanium compound is added in an amount of 10 to 50 with respect to 100 parts by weight of the total amount of the polyphenylene ether, the epoxy resin, and the curing agent.
It is characterized by using what is contained by weight.

[0010] The prepreg according to claim 3 of the present invention, in addition to the constitution of claim 1, as the resin varnish,
It is characterized by using a colorant containing 3 to 50 parts by weight based on 100 parts by weight of the total amount of polyphenylene ether, epoxy resin and curing agent.

[0011] The laminate according to claim 4 of the present invention is characterized in that:
The prepreg according to any one of claims 1 to 3, wherein the prepreg 1 is laminated with a metal foil 2 is manufactured by applying pressure and energizing the metal.

[0012]

Embodiments of the present invention will be described below.

The prepreg 1 according to the present invention is obtained by impregnating a glass varnish made of a woven or nonwoven fabric of glass fiber with a resin varnish and drying the glass varnish. Is prepared as a product impregnated with. It is preferable that the resin impregnation rate in the prepreg 1 be 30 to 70%.

The resin varnish for producing the prepreg 1 is obtained by dissolving a modified phenol product, an epoxy resin, and a curing agent in a solvent.

The above-mentioned modified phenol product is prepared by combining a high-molecular-weight polyphenylene ether having a number average molecular weight of 10,000 to 30,000 and a phenolic compound in the presence of a radical initiator with an aromatic compound such as toluene, benzene, xylene or toluene-chloroform. 80-1 in a group hydrocarbon solvent
It is obtained by reacting at a temperature of 20 ° C. for 10 to 100 minutes. When this reaction is performed, first, the high-molecular-weight polyphenylene ether is radicalized, the high-molecular chain is cut, and a redistribution reaction in which low-molecular-weight polyphenylene ether is generated proceeds. The modified phenol product is produced by the modification with a sex compound. Here, as the polymer polyphenylene ether, poly (2,6-dimethyl-1,4-phenylene oxide)
Etc. can be used. Further, bisphenol A or the like can be used as the phenolic compound. Examples of the radical initiator include peroxides such as benzoyl peroxide and dicumyl peroxide.

The epoxy resin is not particularly limited. For example, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy resin, isocyanurate Examples thereof include a type epoxy resin, an alicyclic epoxy resin, and a polyfunctional epoxy resin. These can be used alone or as a mixture of two or more.

Examples of the curing agent include amines such as commonly used primary or secondary amines, phenols such as bisphenol F, and acid anhydrides. These may be used alone. Or two or more of them can be used by appropriately mixing.

[0018] Examples of the solvent include toluene.

The resin varnish may contain 10 to 50 parts by weight of a titanium compound such as titanium oxide based on 100 parts by weight of the total of the modified phenol product, the epoxy resin and the curing agent. By doing so, it is possible to further suppress the resin flow at the time of forming the laminate. Further, since the color of the cured resin of the laminate manufactured from the prepreg 1 prepared from the resin varnish becomes white and the light reflectance increases, the laminate is preferably used as a printed wiring board for mounting chip LEDs. What can be used.

The resin varnish may contain a colorant such as carbon black in an amount of 3 to 50 parts by weight based on 100 parts by weight of the total of the modified phenol product, the epoxy resin and the curing agent. By doing so, it is possible to further suppress the resin flow at the time of forming the laminate. In addition, when performing a circuit inspection on a printed wiring board obtained by forming a circuit on a laminated board manufactured from the prepreg 1 prepared from the resin varnish by image processing or the like, the color of the cured resin of the laminated board becomes black. In addition, the difference in shading between the circuit portion and the cured resin can be increased, and the circuit pattern can be easily detected.

In the present invention, the prepreg 1 prepared so that the melt viscosity at 170 ° C. of the resin in the B-stage state impregnated in the glass cloth base material is in the range of 5,000 to 50,000 poise. In the present invention, the measurement of the melt viscosity is performed by separating the resin powder from the glass cloth substrate by kneading the prepreg 1 to obtain 2 g of the resin powder.
Is pressurized to form a pellet, and the viscosity is set to 170 ° C. using a curing type flow tester (CFT-100) manufactured by Shimadzu Corporation at a pressure of 5 to 40 kg / cm ² using a 1.0 mm φ nozzle. This was done by measuring.

If the melt viscosity of the resin in the prepreg 1 at 170 ° C. is less than 5000 poise, the flow of the resin at the time of molding becomes too large, and the dispersion of the plate thickness becomes large. Conversely, the melt viscosity of the resin in prepreg 1 at 170 ° C. is 500
If it exceeds 00 poise, the flow of resin during molding is poor. For example, when laminating the inner circuit board, voids are generated between the surface of the inner circuit board and the insulating layer of the prepreg 1, There is a possibility that molding defects such as chipping and measling may occur.

When a metal foil-clad laminate is manufactured using the prepreg 1 of the present invention as described above, a conventional multi-stage hot press causes uneven heating due to uneven heating temperature. Although it is difficult to form a laminated plate by laminating the metal foil 2 on the prepreg 1 and applying heat to the metal foil 2 to generate heat, the molding is easy.

That is, two long metal foils 2 such as copper foils are used, and one or a plurality of prepregs 1 are sandwiched between the two metal foils 2 so that the prepreg 1 and the prepreg 1 are vertically connected. 1, a metal foil 2 is bent in a meandering shape while forming a plurality of sets of the composite material 3 in the longitudinal direction of the metal foil 2 as shown in FIG. A plurality of combination members 3 are combined in multiple stages via the mirror surface plate 4. Then, this is set between the pressure plates 5, the power source 6 is connected to the two metal foils 2, and the metal foil 2 is energized while being cold-pressed by the pressure plates 5. When the metal foil 2 is energized in this way, the metal foil 2 generates heat due to Joule heat, so that each combination material 3 can be heated and formed by this heat generation.

Here, the current is supplied to the metal foil 2 at a heating rate of 3 to 8 ° C./min and a maximum heating temperature of 190 to 200 ° C.
It is preferable to control the temperature to be ° C.

The laminated board formed as described above has a resin flow property constant for each product, and a prepreg obtained by optimizing the resin flow by setting the melt viscosity of the resin component at 170 ° C. to 5,000 to 50,000 poise. By using No. 1, a metal foil-clad laminate can be formed with a very good thickness accuracy and without the problem of occurrence of a flaw. The laminate thus manufactured has a dielectric constant of 3.4 to 3.9 and a dielectric loss tangent of 0.005 to 0.010.
And has high electrical characteristics.

[0027]

The present invention will be described below in detail with reference to examples. (Example 1) Japanese polymer having a number average molecular weight of 20,000 as a polymer polyphenylene ether. E. FIG. Plastics Co., Ltd.
640-111, 100 parts by weight of benzoyl peroxide as a radical initiator, 6 parts by weight of bisphenol A as a phenolic compound, toluene 100
9 while stirring the reaction solution prepared by dissolving
The reaction was carried out by heating at 0 ° C. for 60 minutes to obtain a modified phenol product solution.

Next, the modified phenol product solution was used as an epoxy resin as a part number YDB400 manufactured by Toto Kasei Co., Ltd.
73.1 parts by weight, part number YDB50 manufactured by Toto Kasei Co., Ltd.
0: 53.2 parts by weight, part number EPON1 manufactured by Yuka Shell
031 was added, 6.8 parts by weight of diaminodiphenylmethane was added as a curing agent, 1 part by weight of 2-ethyl-4-methylimidazole was added as a curing accelerator, and 150 parts by weight of toluene was added as a solvent. The mixed solution thus obtained was stirred in a separable flask for 30 minutes and then air-cooled to obtain a resin varnish at 25 ° C.

The resin varnish obtained as described above is
A glass cloth base material of WEA116E type manufactured by Nitto Boseki Co., Ltd. is impregnated so as to have a resin impregnation amount of 46 to 47%.
By drying at a temperature of 70 ° C. for 150 seconds, a prepreg 1 having a thickness of 0.1 mm and a melt viscosity at 170 ° C. of 5000 poise was obtained.

The two prepregs 1 were stacked to a thickness of 18 μm.
A composite material 3 comprising a prepreg 1 and upper and lower metal foils 2 sandwiched between two long metal foils 2 formed of copper foil
As shown in FIG. 1, the metal foil 2 is bent in a meandering manner while forming a plurality of sets of this combination material 3 in the longitudinal direction of the metal foil 2, and a plurality of combinations are formed via an insulating mirror plate 4. Material 3 was combined in multiple stages. This was set between the pressure plates 5, and a power source 6 was connected to the metal foil 2.

After that, the pressure plate 5
While applying pressure at a pressure of / cm ² , the metal foil 2 is heated and pressurized for 110 minutes by causing heat to be generated by heating.
A laminate having dimensions of 510 mm x 0.2 mmt was prepared. Here, the energization of the metal foil 2 was controlled so that the temperature was raised to 200 ° C. at a rate of 3.5 ° C./min and maintained at a temperature of 200 ° C. for 30 minutes. (Example 2) Araldite DW-01 (trade name, manufactured by Ciba Specialty Chemicals Co., Ltd.) was obtained by dispersing titanium oxide in the resin varnish obtained in Example 1.
Was added, and the mixture of titanium oxide and 50 parts by weight with respect to the total amount of 100 parts by weight of the modified phenylene product, epoxy resin, and curing agent was stirred and dispersed for 1 hour to obtain a resin varnish. .

Using this resin varnish, prepreg 1 having a melt viscosity of 20,000 poise was obtained in the same manner as in Example 1. Using this prepreg 1, a laminate having a size of 340 mm × 510 mm × 0.2 mmt was produced under the same conditions as in Example 1. (Example 3) Araldite DW (trade name, manufactured by Ciba Specialty Chemicals Co., Ltd.) as a colored paste obtained by dispersing carbon black in the resin varnish obtained in Example 1
-07 was added, the modified phenylene product, the epoxy resin, and the mixture of carbon black with respect to 100 parts by weight of the total amount of the curing agent were mixed with 50 parts by weight for 1 hour to be dispersed by stirring. Obtained.

Using this resin varnish, prepreg 1 having a melt viscosity of 50,000 poise was obtained in the same manner as in Example 1. Using this prepreg 1, a laminate having a size of 340 mm × 510 mm × 0.2 mmt was produced under the same conditions as in Example 1. (Comparative Example 1) The resin varnish obtained in Example 1 was impregnated into a WEA116E type glass cloth substrate manufactured by Nitto Boseki Co., Ltd. so that the resin impregnation amount was 46 to 47%, and 170 ° C.
0.1m thick by drying at 130 ° C for 130 seconds
m, the prepreg 1 having a melt viscosity at 170 ° C. of 4000 poise was obtained.

Using this prepreg 1, a laminate having a size of 340 mm × 510 mm × 0.2 mmt was manufactured under the same conditions as in Example 1. (Comparative Example 2) 0.1 mm in thickness and 1
A prepreg 1 having a melt viscosity at 70 ° C. of 4000 poise was obtained.

Two prepregs 1 were stacked, and a copper foil having a thickness of 18 μm was laminated on both surfaces thereof, and the copper foils were laminated in 10 steps via a stainless steel mirror plate. This is placed between the hot platen plates, and subjected to conventional hot press molding in which pressure is applied and heated using a hot platen, and 340 m
A laminate having dimensions of mx 510 mm x 0.2 mmt was prepared. Here, the heating and pressing conditions are 200 ° C. and 30 kg / cm.
As No. ² , heating and pressurization were performed under these conditions for 30 minutes. (Comparative Example 3) Thickness 0.1 mm, 1
Prepreg 1 with 20,000 poise melt viscosity at 70 ° C
I got

Using this prepreg 1, hot press molding was performed under the same conditions as in Comparative Example 2, and 340 mm × 51
A laminate having a size of 0 mm × 0.2 mmt was produced. (Comparative Example 4) 0.1 mm thick, 1
Prepreg 1 whose melt viscosity at 70 ° C is 50,000 poise
I got

Using this prepreg 1, hot press molding was performed under the same conditions as in Comparative Example 2, and 340 mm × 51
A laminate having a size of 0 mm × 0.2 mmt was produced. (Evaluation Test) For the laminates obtained in the above-described Examples and Comparative Examples, which were subjected to etching treatment to remove the copper foil, the standard deviation of the plate thickness was measured and the appearance was inspected. .

For the measurement of the standard deviation of the plate thickness, ten samples were prepared for each of the examples and comparative examples. The measurement was performed using a micrometer, and the standard deviation was determined from the measurement results.

In the appearance inspection, the standard deviation of the plate thickness was measured. Ten samples were prepared for each of the examples and comparative examples, and the surface of the sample from which the copper foil had been removed was visually observed. This was performed by confirming the presence or absence of blurring, measling, and voids.

Table 1 shows the results.

[0041]

[Table 1] As is clear from Table 1, the metal foil 2 is energized to
Pressed by a method of heating the prepreg 1
In Examples 1 to 3 having a melt viscosity at 170 ° C. of 5,000 to 50,000 poise, it was confirmed that the standard deviation of the plate thickness was small, and no generation of blurring, measling, and voids occurred.

On the other hand, the melt viscosity of prepreg 1 is 4000
In the case of Comparative Example 1 which was poise, it was confirmed that the resin flow increased and the standard deviation of the plate thickness increased.

In Comparative Examples 1 to 4, the melt viscosity at 170 ° C. was 5000
It was confirmed that when the laminated plate was formed using the prepreg 1 having a size of up to 50,000 poise, the standard deviation of the plate pressure was large and defects such as fraying were also observed.

[0044]

As described above, in the prepreg according to the first aspect of the present invention, the metal foil laminated on the prepreg is energized to generate heat, whereby the resin component of the prepreg is cured to form a laminate. In a prepreg used for production, a resin varnish containing a polyphenylene ether, an epoxy resin, and a curing agent is obtained by impregnating and drying a substrate, and the resin component has a melt viscosity at 170 ° C. of 500.
Because the flow of resin at the time of molding is optimal because it is 0 to 50,000 poise, there is no problem of molding defects such as variations in plate thickness and product scumming. A foil-clad laminate can be manufactured.

A prepreg according to a second aspect of the present invention is the same as the first aspect, except that
The titanium compound is added in an amount of 10 to 50 with respect to 100 parts by weight of the total amount of the polyphenylene ether, the epoxy resin, and the curing agent.
The use of the resin containing a part by weight can further suppress the resin flow at the time of molding the laminate. Also, the color of the cured resin of the laminated board manufactured from this prepreg becomes white,
Since the light reflectance is high, this laminated plate is used as a chip LE.
It can be suitably used as a printed wiring board for mounting D.

The prepreg according to the third aspect of the present invention is the same as the first aspect, except that
Since a colorant containing 3 to 50 parts by weight is used based on 100 parts by weight of the total amount of the polyphenylene ether, epoxy resin, and curing agent, the resin flow at the time of molding the laminate can be further suppressed. In addition, when performing a circuit inspection of a printed wiring board obtained by performing circuit formation on a laminated board manufactured from this prepreg by image processing or the like, it is possible to increase the difference in shading between the circuit portion and the cured resin by a colorant, The circuit pattern can be easily detected.

The laminate according to claim 4 of the present invention comprises:
Since the prepreg according to any one of claims 1 to 3 is manufactured by applying pressure to a metal foil laminated with a metal foil and energizing the metal, there is no problem such as a variation in plate thickness or a thin product. .

[Brief description of the drawings]

FIG. 1 is a schematic front view showing an example of an embodiment of the present invention.

[Explanation of symbols]

 1 Pre-preg 2 Metal foil

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-200054 (JP, A) JP-A-9-124806 (JP, A) JP-A-9-227659 (JP, A) JP-A-9-92 235349 (JP, A) JP-A-9-239898 (JP, A) JP-A-9-291148 (JP, A) JP-A 10-17685 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) B32B 1/00-35/00 C08J 5/24

Claims (4)

(57) [Claims] 1. A prepreg used for producing a laminate by curing a resin component of a prepreg by applying a current to a metal foil laminated on the prepreg to generate heat, the modified phenol product, epoxy resin, resin,
And a resin varnish containing a curing agent is impregnated into the substrate and dried to obtain a resin component having a melt viscosity at 170 ° C. of 5,000 to 5,000.
A prepreg comprising 50,000 poise. 2. A resin varnish comprising 10 to 50 parts by weight of a titanium compound with respect to 100 parts by weight of a total of polyphenylene ether, epoxy resin and curing agent. 2. The prepreg according to 1. 3. The resin varnish according to claim 1, wherein the resin varnish contains 3 to 50 parts by weight of a coloring agent based on 100 parts by weight of the total amount of polyphenylene ether, epoxy resin, and curing agent. 2. The prepreg according to 1. 4. A laminated plate manufactured by pressing a prepreg according to any one of claims 1 to 3 and laminating a metal foil and applying a current to the metal.