JPH06335992A - Production of metal foil clad laminated sheet and metal foil used therein - Google Patents

Abstract

PURPOSE:To ensure the reduction of the elasticity of a surface layer necessary for ensuring, the solder connection reliability of SMD and the peeling strength and heat resistance of a metal foil as a metal foil clad laminated sheet suitable for the substrate of an SMD corresponding printed wiring board. CONSTITUTION:An adhesive compsn. containing acrylonitrile/butadiene rubber, an epoxy resin, a phenol resin and an inorg. filler (aluminum hydroxide) as essential components is preliminarily applied to a metal foil. The compounding amt. of the inorg. filler is set to 60wt.% or less as a solid wt. basis. This metal foil is molded along with a prepreg under heating and pressure to produce a metal foil clad laminated sheet. In order to suppress the mutual blocking of the metal foils when the metal foils coated with the adhesive compsn. are superposed one upon another, 50 pts.wt. or less of modified silicone may be added to 100 pts.wt. of the adhesive compsn. when acrylic rubber is used in place of acrylonitrile/butadiene rubber, the discoloration of the laminated sheet due to heat is reduced.

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 metal foil-clad laminate suitable as a material for printed wiring boards.

[0002]

2. Description of the Related Art With the recent trend toward higher density, higher integration and smaller size of electronic and electrical equipment, components mounted on a printed wiring board to be incorporated therein are also changed from insertion type discrete components to surface mount type SMDs. Is moving to. As for the SMD compatible printed wiring board,
There is a problem of reliability of the solder connection portion between the SMD and the printed wiring. That is, the coefficient of thermal expansion in the plane direction of the laminated board which is the substrate of the printed wiring is considerably larger than the coefficient of thermal expansion of SMD. Therefore, when the cooling / heating cycle is repeated, the stress caused by the difference in the coefficient of thermal expansion acts on the solder connection portion each time, and the solder connection portion is likely to be cracked. Therefore, the elasticity of the laminated board, which is the board material of the printed wiring board, is reduced in the plane direction so that the stress due to the difference in the thermal expansion coefficient between the SMD and the board is absorbed by the board having the low elasticity, and the solder connection portion has a large It is considered to prevent the stress from working. The laminated plate is obtained by impregnating a sheet-like base material with a thermosetting resin,
It is manufactured by stacking and stacking them under heat and pressure. For example, a flexibility-imparting agent is added to the thermosetting resin, or the added flexibility-imparting agent is reacted with the thermosetting resin. Technology for lowering elasticity has been studied. Further, when the thermosetting resin contains an inorganic filler, atomization and spheroidization of the inorganic filler have been studied.

[0003]

However, although the conventional technique for lowering the elasticity can lower the elastic modulus of the laminated board, other characteristics required for the printed wiring board, that is, heat resistance and metal are required. There was a problem that the peeling strength of the foil was reduced. The problem to be solved by the present invention is, as a metal foil-clad laminate suitable for a substrate of an SMD-compatible printed wiring board, a low elasticity required for ensuring solder connection reliability, as well as heat resistance and metal foil. It is to secure the peeling strength.

[0004]

In order to solve the above-mentioned problems, the manufacturing method according to the present invention involves placing a metal foil on the surface of a layer of a sheet-like base material impregnated with a thermosetting resin, In the production of a metal foil-clad laminate that is heat-pressed, the metal foil has the following (1) to (4) on the contact surface to the sheet-shaped substrate.
The adhesive composition (A) containing the above component as an essential component is applied in advance. (1) Acrylonitrile butadiene rubber (2) Epoxy resin (3) Phenolic resin (4) Inorganic filler However, the compounding amount of the inorganic filler is 6 in terms of solid content in the adhesive.
It should be 0% by weight or less. Another manufacturing method according to the present invention is the following (1) to (4) on the contact surface of the metal foil with the sheet-shaped substrate.
The adhesive composition (B) containing the above component as an essential component is applied in advance. (1) Acrylic rubber (2) Epoxy resin (3) Curing agent for epoxy resin (4) Inorganic filler However, the compounding amount of the inorganic filler is 60 in terms of solid content of the adhesive.
Reduce to less than weight%. In the adhesive composition (A) or (B), the inorganic filler is preferably aluminum hydroxide. The metal foil for producing a laminate according to the present invention is obtained by applying the adhesive composition (A) or (B). It is preferable that the modified silicone is contained in an amount of 50 parts or less with respect to 100 parts (weight of solid content) of the adhesive composition (A) or (B).

[0005]

In the method according to the present invention, acrylonitrile butadiene rubber, epoxy resin, phenol resin, inorganic filler (aluminum hydroxide, etc.) is directly under the metal foil integrally attached to the surface of the laminate by heat and pressure molding. Of the adhesive composition (A) containing, as an essential component, or an adhesive composition (B) containing acrylic rubber, an epoxy resin, a curing agent for an epoxy resin, and an inorganic filler (such as aluminum hydroxide) as an essential component. By forming the layer (1), the elasticity of the substrate surface is reduced without deteriorating the characteristics required as a substrate of a printed wiring board, and the reliability of solder connection is ensured as an SMD compatible substrate. The acrylonitrile butadiene rubber and acrylic rubber are used to impart flexibility to the layer of the adhesive composition and reduce the elastic modulus, and when these are used alone as an adhesive, It lowers heat resistance and peeling strength of metal foil. Also, when only an epoxy resin is added to the acrylonitrile butadiene rubber or acrylic rubber and used as an adhesive, the heat resistance of the laminated plate and the peeling strength of the metal foil are similarly reduced. In the layer of the adhesive composition (A), by adding a phenol resin to the layer, the acrylonitrile butadiene rubber is present in the cured product of the epoxy resin and the phenol resin in a sea-island structure, and the adhesive and the metal foil are formed. Has improved adhesiveness and suppresses deterioration of heat resistance. Further, in the layer of the adhesive composition (B), by adding a curing agent for the epoxy resin (the above-mentioned phenol resin is also a curing agent for the epoxy resin, but is not limited to this), the epoxy resin is similarly cured. The vulcanized rubber is present in the cured product in a sea-island structure to improve the adhesiveness between the adhesive and the metal foil and suppress the decrease in heat resistance. However, since the peeling strength of the metal foil necessary and sufficient for the substrate of the printed wiring board has not yet been reached, the peeling strength of the metal foil can be maintained by adding an inorganic filler such as aluminum hydroxide to this. Is possible. However, when the content of the inorganic filler exceeds 60% by weight in terms of solid content in the adhesive, the elastic modulus of the adhesive layer effective for lowering the elasticity becomes high and the solder connection reliability cannot be ensured. . The adhesive composition having the above-mentioned composition is applied to the surface of a laminated plate on which no metal foil is attached and dried, and the metal foil is attached to the surface by heating and pressing. It is impossible to obtain sufficient heat resistance and peeling strength of the metal foil as the substrate. Required as a substrate for a printed wiring board by applying an adhesive composition having the above composition to a metal foil in advance and heat-pressing it together with a layer of a sheet-like base material (prepreg) impregnated with a thermosetting resin. It is possible to achieve low elasticity without deteriorating various characteristics and to secure solder connection reliability as an SMD compatible substrate.

The surface of the metal foil coated with the above-mentioned adhesive composition (A) or (B) may be dried even if it is dried because acrylonitrile butadiene rubber or acrylic rubber is a relatively high molecular weight substance with low reactivity. Sticky remains. For this reason,
If multiple metal foils are left stacked, the surface coated with the adhesive composition may stick to the surface of the metal foil overlaid with the adhesive composition that is not coated with the adhesive composition. It may happen. However, by adding the modified silicone to the adhesive composition (A) or (B), it is possible to prevent the tackiness from remaining on the coated surface of the adhesive composition and improve the blocking phenomenon. The amount of the modified silicone compounded is 1 for the adhesive composition (A) or (B).
When it exceeds 50 parts with respect to 00 parts (solid content equivalent weight),
Since the peeling strength of the metal foil on the surface of the laminate decreases,
It should be 50 parts or less. If aluminum hydroxide is selected as the inorganic filler contained in the adhesive composition (A) or (B), when high-temperature stress is applied to the surface of the laminate, the stress is absorbed by the thermal decomposition of aluminum hydroxide. ,ease. By such an action, the soldering iron repairability of the printed wiring board (By re-soldering,
It also has the effect of improving this with respect to the number of times soldering is repeated until peeling and blistering of the metal foil occur.

Acrylic rubber has no unsaturated bond in the molecule. Therefore, the metal foil-clad laminate using the adhesive composition (B) is better than the metal foil-clad laminate using the adhesive composition (A) (acrylonitrile butadiene rubber has an unsaturated bond in the molecule). As a result, a stable color tone can be maintained with little thermal discoloration due to heating such as soldering.

[0008]

EXAMPLE The sheet-like substrate used in the method according to the present invention is, for example, a glass woven fabric, a glass nonwoven fabric, a glass-paper mixed nonwoven fabric, or an aramid nonwoven fabric, and is not particularly limited. As the thermosetting resin with which these sheet-shaped base materials are impregnated, epoxy resin, phenol resin, urea resin, polyimide or the like can be appropriately used. These thermosetting resins include inorganic fillers (Al ₂ O ₃ , Al ₂ O ₃ · H ₂ O, Al ₂ O ₃ ) for the purpose of quality improvement, workability improvement, cost reduction, etc.
O ₃ · 3H ₂ O, talc, MgO, etc. SiO ₂₎ may be compounded. The metal foil-clad laminate produced by the method according to the present invention has a sheet-shaped substrate made of a glass woven fabric alone, a glass woven fabric and a glass nonwoven fabric type, an aramid nonwoven fabric alone type, and the above-mentioned substrate composite. And the type used. It also includes a metal foil-clad laminate for a multilayer printed wiring board. The metal foil used in the method according to the present invention is a copper foil, an aluminum foil, or the like, but is not particularly limited.

The acrylonitrile butadiene rubber used as a component of the adhesive composition (A) in the method according to the present invention is preferably of a type having a carboxyl group or an epoxy group at the terminal, as shown in Chemical formula 1. However, it is not particularly limited. Similarly, the acrylic rubber used as a component of the adhesive composition (B) is also preferably of a type having a carboxyl group or an epoxy group at its side chain or terminal and capable of being crosslinked with an epoxy resin, but it is particularly limited. is not. The epoxy resin used as a component of the adhesive composition (A) or (B) in the method according to the present invention is preferably a bisphenol A type epoxy resin, a phenol novolac type epoxy resin, or a cresol novolac type epoxy resin. There is no particular limitation, and bisphenol S type epoxy resin, bisphenol F type epoxy resin, alicyclic epoxy resin, naphthalene type epoxy resin and the like can be used alone or in combination. The phenol resin used as a component of the adhesive composition (A) in the method according to the present invention is not particularly limited as long as it reacts with an epoxy resin, and phenol,
Phenol novolac resins made of alkylphenol, cresol and the like can be used alone or in admixture of several kinds. Further, the curing agent for the epoxy resin used as a component of the adhesive composition (B) is
Since generally commercially available acrylic rubber contains a small amount of acrylonitrile groups, a type such as a phenol resin which can react with this and crosslink with an epoxy resin is preferable. However, it is not particularly limited as long as it reacts with the epoxy resin, and dicyandiamide, dimethylbenzylamine and the like can be appropriately used alone or in combination of several kinds. The inorganic filler used as a component of the adhesive composition in the method according to the present invention is preferably aluminum hydroxide, but aluminum oxide (Al ₂ O ₃ , Al ₂ O ₃ .H ₂ O, etc.), silica (SiO ₂ )
Etc. can also be used. When aluminum hydroxide is used, it preferably has an average particle size of 0.5 to 10 μm, but is not particularly limited. Further, aluminum hydroxide particles whose surface is treated with a silane coupling agent or the like can also be used. Further, it is preferable to mix the inorganic filler in an amount of about 20 to 40% by weight, because the characteristics balance such as peeling strength of the metal foil and solder connection reliability is good. The modified silicone used in the method according to the present invention is
As shown in (Chemical Formula 2), an amino-modified or epoxy-modified reactive silicon having a functional group such as an amino group or an epoxy group in a side chain or terminal is preferable, but polyether-modified or alkyl-modified Non-reactive silicon may be used and is not particularly limited.

[0010]

[Chemical 1]

[0011]

[Chemical 2]

Examples 1 to 7 and Comparative Examples 1 to 7 (using acrylonitrile butadiene rubber as a rubber component) (Preparation of adhesive composition) Acrylonitrile butadiene rubbers having carboxyl groups at both ends were compounded at the compounding amounts shown in Tables 1 and 2. (Ube Industries, Ltd. “CTBN”), bisphenol A type epoxy resin (Okaka Shell Epoxy “Ep-828”),
Novolac-type phenol resin (Dainippon Ink's "TD-
2093 ") and aluminum hydroxide as a curing accelerator, 2-ethyl-4-methyl-imidazole (2E).
4MZ) was added at 0.5 parts by weight. To mix these,
1/1 by weight ratio of cellosolve acetate and methyl ethyl ketone
The mixed solvent of was used and stirred with a homomixer to dissolve and disperse, to prepare an adhesive composition (A) having a solid content of 30% by weight. (Application of Adhesive Composition to Copper Foil) Adhesive Composition (A)
Was applied to the roughened surface of a copper foil having a thickness of 35 μm so that the adhesive layer thickness after drying would be 30 μm, and dried by heating at 160 ° C. for 60 minutes to give the adhesive layer-attached copper foil (A). Obtained. (Molding of metal foil-clad laminate) A bisphenol A type epoxy resin varnish was impregnated into a glass woven fabric having a unit weight of 205 g / m ² and dried to obtain a prepreg (A) having a resin adhesion amount of 40% by weight. Also, a bisphenol A type epoxy resin varnish containing an inorganic filler (resin / filler weight ratio = 1
00/50) was impregnated into a glass nonwoven fabric having a unit weight of 50 g / m ² and dried to obtain a prepreg (B) containing a filler and having a resin adhesion amount of 84% by weight. 6 plies of prepreg (B) are stacked, 1 ply of prepreg (A) is placed on each side of the prepreg, and 1 ply of copper foil (A) with an adhesive layer is placed on each side with the adhesive layer side facing inward. A 1.6 mm thick composite type copper clad laminate was obtained by heat and pressure molding.

[0013]

[Table 1]

[0014]

[Table 2]

Comparative Example 8 Six plies of prepreg (B) were superposed, one ply of prepreg (A) was placed on each side of the prepreg, and a polyacetate film was placed on both sides of the prepreg (B). The acetate film was peeled off to obtain a 1.6 mm thick composite type laminate. The adhesive composition (A) of Example 2 was applied to the surface of this laminate so that the thickness of the adhesive layer after drying would be 30 μm, and heat-dried at 160 ° C. for 60 minutes to obtain the laminate surface. An adhesive layer was formed on. And
Place 35μm thick copper foil (without adhesive layer) on both surfaces,
A 1.6 mm thick composite type copper clad laminate was obtained by heat and pressure molding.

Conventional Example 1 40 parts by weight of a bisphenol A type epoxy resin (“Ep-828” manufactured by Yuka Shell Epoxy) is added to 100 parts by weight of a carboxyl-terminated acrylonitrile butadiene rubber (“CTBN” manufactured by Ube Industries). 2 as a curing accelerator
0.5 parts by weight of E4MZ, toluene 30 as a diluting solvent
Parts by weight were compounded and reacted at 100 ° C. for 2 hours to prepare an butadiene acrylonitrile rubber epoxidized at both ends. 50 parts by weight of the above-mentioned both-end-epoxidized butadiene acrylonitrile rubber was added to bisphenol A type epoxy resin 10
A unit weight of 205 g / m ^{2 of} varnish blended in 0 part by weight
This was impregnated and dried in a glass woven fabric to obtain a prepreg (C) having a resin adhesion amount of 40% by weight. 6 plies of prepreg (B) are stacked, 1 ply of prepreg (C) is placed on each side, and 1 ply of 35 μm thick copper foil (without adhesive layer) is placed on both sides of the prepreg (B), and heat and pressure molding is performed. Thickness 1.6
A mm type composite type copper clad laminate was obtained.

Conventional Example 2 Six plies of prepreg (B) are superposed, one ply of prepreg (A) is arranged on each side of the prepreg (B), and 35 μm is formed on each side.
A thick copper foil (without an adhesive layer) was placed on each ply and subjected to heat and pressure molding to obtain a 1.6 mm thick composite type copper clad laminate.

The characteristics of each of the above laminated plates are shown in Tables 3 and 4.
The evaluation method of each property in the table is as follows. (1) Copper foil peeling strength: JIS method (2) Solder heat resistance: Normal sample is immersed in a solder bath at 300 ° C and the time until blistering occurs on the sample surface is measured (3) Solder crack: 100 samples (100 each mounted in the vertical direction and the horizontal direction of the base material) to which # 3125 chips were solder-connected by the surface mounting method were subjected to a cold heat repetition test at -30 ° C and 120 ° C, and cracks occurred after 1000 cycles. (4) Solder iron repairability: A 50 x 50 mm copper clad laminate was etched to leave a 1 x 1 mm copper foil in the center as a sample and heated to 380 ° C. 1 soldering iron on the copper foil
After applying for 0 seconds, check the copper foil for peeling and blistering, repeat the above operation, and measure the number of operations until peeling and blistering on the copper foil (5) Copper foil blocking property: 50 5 pieces of copper foil samples of x 50 mm are stacked, and a load of 500 g is applied from the top and left for 24 hours to confirm the sticking condition of the copper foils ○: No or almost no blocking △: Sticking, Easy to peel off x: Completely blocked and difficult to peel off

[0019]

[Table 3]

[0020]

[Table 4]

Examples 8 to 14, Comparative Examples 9 to 14 (Acrylic rubber is used as rubber component) (Preparation of adhesive composition) Acrylic rubber ("LX852" manufactured by Nippon Zeon Co., Ltd.) was used in the compounding amounts shown in Tables 5 and 6. )), Bisphenol A type epoxy resin (“Ep
-828 "), a novolac type phenolic resin (" TD-2093 "manufactured by Dainippon Ink and Co., Ltd.), and aluminum hydroxide were added with 0.5 part by weight of 2E4MZ as a curing accelerator. For mixing these, a mixed solvent of cellosolve acetate and methyl ethyl ketone in a weight ratio of 1/1 was used, and the mixture was stirred with a homomixer and dissolved and dispersed to prepare an adhesive composition (B) having a solid content of 30% by weight. (Application of Adhesive Composition to Copper Foil) Adhesive Composition (B)
Was applied to the roughened surface of a copper foil having a thickness of 35 μm so that the adhesive layer thickness after drying would be 30 μm, and dried by heating at 160 ° C. for 60 minutes to give an adhesive layer-attached copper foil (B). Obtained. (Molding of metal foil-clad laminate) 6 plies of prepreg (B) are stacked, 1 ply of prepreg (A) is placed on each side of the prepreg (B), and copper foil (B) with an adhesive layer is placed on both sides inside the adhesive layer. Then, each ply was placed one by one and subjected to heat and pressure molding to obtain a 1.6 mm thick composite type copper clad laminate.

Example 15 A dicyandiamide was used in place of the novolac type phenol resin, and an adhesive composition was prepared in the same manner with the compounding ratio shown in Table 5. Using this adhesive composition, a 1.6 mm thick composite type copper clad laminate was obtained in the same manner.

[0023]

[Table 5]

[0024]

[Table 6]

Comparative Example 15 Six plies of prepreg (B) were stacked, one ply of prepreg (A) was placed on each side of the prepreg, and a polyacetate film was placed on both sides of the prepreg (A). The acetate film was peeled off to obtain a 1.6 mm thick composite type laminate. The adhesive composition (B) of Example 9 was applied to the surface of this laminate so that the thickness of the adhesive layer after drying would be 30 μm, and heat-dried at 160 ° C. for 60 minutes to obtain the laminate surface. An adhesive layer was formed on. And
Place 35μm thick copper foil (without adhesive layer) on both surfaces,
A 1.6 mm thick composite type copper clad laminate was obtained by heat and pressure molding.

The characteristics of each laminated plate are shown in Tables 7 and 8.
The evaluation method of each property in the table is the same as in Tables 3 and 4. However, the time-dependent discoloration of the laminate was evaluated as follows. The copper-clad laminate of 50 x 50 mm is etched on the whole surface and repeated at -30 ° C and 120 ° C for 100 times.
The degree of discoloration of the surface is observed after 0 cycle. A: No discoloration is seen B: Discoloration is visible when viewed side by side with the sample before aging C: Discoloration can be seen at a glance The copper-clad laminate of Example 1 (acrylonitrile butadiene rubber as a rubber component) Was used), and the discoloration with time was evaluated, and the evaluation was "C".

[0027]

[Table 7]

[0028]

[Table 8]

[0029]

As is apparent from Table 3, Table 4 and Table 7 and Table 8, the method according to the present invention has characteristics suitable as a metal foil-clad laminate used for a substrate of an SMD compatible printed wiring board. That is, it is possible to secure the peeling strength and heat resistance of the metal foil in addition to lowering the elasticity of the surface layer centering on the surface direction necessary for securing the solder connection reliability of the SMD. When aluminum hydroxide is used as the inorganic filler, when a high heat load is applied to the surface of the laminate, the stress is absorbed by the thermal decomposition of aluminum hydroxide,
Will be alleviated. Due to such an action, the soldering iron repairability of the printed wiring board (repeating soldering at the same place causes peeling and swelling of the metal foil, but the number of times soldering is repeated until peeling and swelling of the metal foil) Can be improved. By improving the soldering iron repairability, the solder connection reliability of the conventional manual soldering method using a soldering iron is improved, and it is a laminated board for printed wiring boards suitable for consumer boards, etc. be able to. Also,
When the modified silicone is added to the adhesive composition in an amount of 50 parts by weight or less based on 100 parts by weight of the adhesive composition, blocking between metal foils that occurs when the metal foil coated with the adhesive composition is left stacked is also caused. Can be suppressed. And
The characteristics of the metal foil-clad laminate are not deteriorated due to the limitation of the blending amount. In the invention in which acrylic rubber is selected as the rubber component of the adhesive composition, the surface of the laminate is less discolored by heat and the appearance is excellent.

Front page continuation (72) Inventor Manri Kamata 2-1, 1-1 Nishishinjuku, Shinjuku-ku, Tokyo Shin-Kindo Electric Co., Ltd.

Claims (8)

[Claims] 1. In the production of a metal foil-clad laminate in which a metal foil is placed on the surface of a layer of a sheet-shaped base material impregnated with a thermosetting resin, and the metal foil is laminated under heat and pressure, the metal foil is a sheet. A method for producing a metal foil-clad laminate, characterized in that the adhesive composition (A) containing the following components (1) to (4) as essential components is applied in advance to the contact surface with the substrate. . (1) Acrylonitrile butadiene rubber (2) Epoxy resin (3) Phenolic resin (4) Inorganic filler However, the compounding amount of the inorganic filler is 6 in terms of solid content in the adhesive.
It should be 0% by weight or less. 2. A metal foil for producing a metal foil-clad laminate, which is obtained by applying an adhesive composition (A) containing the following components (1) to (4) as essential components. (1) Acrylonitrile butadiene rubber (2) Epoxy resin (3) Phenolic resin (4) Inorganic filler However, the compounding amount of the inorganic filler is 6 in terms of solid content in the adhesive.
It should be 0% by weight or less. 3. In the production of a metal foil-clad laminate in which a metal foil is placed on the surface of a layer of a sheet-shaped base material impregnated with a thermosetting resin, and the metal foil is laminated under heat and pressure, the metal foil is a sheet. A method for producing a metal foil-clad laminate, characterized in that the adhesive composition (B) containing the following components (1) to (4) as essential components is applied in advance to the contact surface with the substrate. . (1) Acrylic rubber (2) Epoxy resin (3) Curing agent for epoxy resin (4) Inorganic filler However, the compounding amount of the inorganic filler is 60 in terms of solid content of the adhesive.
Reduce to less than weight%. 4. A metal foil for producing a metal foil-clad laminate, which is obtained by applying an adhesive composition (B) containing the following components (1) to (4) as essential components. (1) Acrylic rubber (2) Epoxy resin (3) Curing agent for epoxy resin (4) Inorganic filler However, the compounding amount of the inorganic filler is 60 in terms of solid content of the adhesive.
Reduce to less than weight%. 5. The method for producing a metal foil-clad laminate according to claim 1, wherein the inorganic filler is aluminum hydroxide. 6. The adhesive composition 100 in terms of solid content conversion weight ratio.
6. The method for producing a metal foil-clad laminate according to claim 1, wherein the modified silicon is mixed in an amount of 50 parts or less per part. 7. The metal foil for producing a metal foil-clad laminate according to claim 2, wherein the inorganic filler is aluminum hydroxide. 8. The adhesive composition 100 in terms of solid content conversion weight ratio.
The metal foil for producing a metal foil-clad laminate according to claim 2, wherein the modified silicon is contained in an amount of 50 parts or less per part.