JP2001316563A - Electrical insulating resin composition, copper-foiled electrical insulating material and copper-clad laminated board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject resin composition flame-retardative without using any halogen-based flame retardant, capable of making non-halogen-based flame-retardant copper-foiled electrical insulating materials, and also excellent in heat resistance and reliability, and to obtain such copper-foiled electrical insulating materials and copper-clad laminated boards each excellent in flame retardancy, heat resistance and reliability and capable of responding to the demand for environmental compatibility by using the above resin composition. SOLUTION: This resin composition essentially comprises an epoxy resin, an epoxy resin curing agent, electrical insulating whisker, metal hydroxide(s) and a multiple oxide of flame-retarding auxiliary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an insulating resin composition,
The present invention relates to an insulating material with copper foil and a copper-clad laminate.

[0002]

2. Description of the Related Art Conventionally, an epoxy resin composition comprising an epoxy resin, an epoxy resin curing agent and a curing accelerator has been used as a resin composition. Further, since it is necessary to impart flame retardancy to the printed wiring board, a compound having a halogen element such as bromine is generally added as a flame retardant. Specifically, decabromodiphenyl ether, tetrabromobisphenol A, brominated bisphenol A type epoxy resin and the like are used as these flame retardants.

[0003] A multilayer printed wiring board is a wiring board having an electric circuit also in an inner layer. This multilayer printed wiring board is formed on the outer layer surface of a copper-clad laminate containing an inner printed wiring board in which a circuit formed in advance and a copper foil as an outer wiring material are integrated by hot pressing through a prepreg. Obtained by forming a circuit. Conventionally, the prepreg is a glass cloth prepreg obtained by impregnating a glass cloth with an epoxy resin and drying the resin to a semi-cured state, or an adhesive film formed of a prepreg that does not use a glass cloth and having a film-forming resin in a semi-cured state. (See JP-A-6-200216 and JP-A-6-242465) and an adhesive film with a copper foil in which the adhesive film is formed on one side of a copper foil (see JP-A-6-196682).
Is used. The film-forming ability referred to here means that troubles such as cracking or chipping of the resin hardly occur during the steps of transporting, cutting, and laminating the prepreg, and the interlayer insulating layer is formed in the portion where the inner layer circuit exists at the time of subsequent hot pressing. It means performance that is unlikely to cause troubles such as abnormal thinning, reduction in interlayer insulation resistance and short circuit.

[0004]

In recent years, the use of non-halogen flame-retardant resins has been required due to environmental problems. In addition, as electronic devices become smaller, higher in performance, and lower in cost, printed wiring boards are required to have higher density, thinner, higher reliability, and lower cost. Multilayering is being performed to increase the density of printed wiring boards, and thinning is being dealt with by reducing the thickness of the inner substrate and prepreg, but when the prepreg using glass cloth is made thinner, The reliability such as heat resistance and electric corrosion resistance is reduced.

On the other hand, an adhesive film without glass cloth or an adhesive film with a copper foil can be made thinner, and is excellent in small-diameter drill workability, laser hole workability, and surface smoothness.
However, the multilayer printed wiring board made of these prepregs has extremely low rigidity because the outer insulating layer has no glass cloth base material. This low rigidity is extremely remarkable at a high temperature, and is likely to bend in the component mounting process, and the wire bonding property is extremely poor.

In addition, since the outer insulating layer has no glass cloth substrate and has a large thermal expansion coefficient, the difference in thermal expansion from the mounted component is large, the connection reliability with the mounted component is low, and the thermal expansion and contraction during heating and cooling causes There are many problems such as cracks and breaks easily occurring in the solder connection part. Therefore, it is not possible to meet the increasing demand for thinner and higher density multilayer printed wiring boards using the current adhesive film without glass cloth or adhesive film with copper foil.

Accordingly, the present invention provides an insulating resin composition using a non-halogen flame-retardant resin and having excellent heat resistance and reliability, and an insulating material with a copper foil using the same.

[0008]

The present invention relates to the following. (1) An insulating resin composition containing, as essential components, an epoxy resin, an epoxy resin curing agent, an electrically insulating whisker, a metal hydroxide, and a double oxide of a flame retardant aid. (2) With respect to the total amount of the epoxy resin, the epoxy resin curing agent, the curing accelerator optionally used, and the additive optionally used, the total amount of the nitrogen element contained in these compounds is The insulating resin composition according to (1), which is 0.5% by weight or more. (3) The insulating resin composition according to any of (1) or (2), wherein the epoxy resin curing agent is a dicyandiamide or melamine-modified phenol novolak resin. (4) The total amount of the phosphorus element is 0.1% by weight or more with respect to the total amount of the epoxy resin, the epoxy resin curing agent, the curing accelerator optionally used, and the additive optionally used. The insulating resin composition according to any one of (1) to (3). (5) The insulating resin composition according to any one of (1) to (4), which contains a phosphate compound as a component of the resin composition. (6) The total of the electrically insulating whisker and the metal hydroxide is 10% by volume or more (1) to (5).
3. The insulating resin composition according to item 1. (7) The electrically insulating whisker is aluminum borate and / or magnesium borate (1).
The insulating resin composition according to any one of (1) to (6). (8) The metal hydroxide is aluminum hydroxide and / or magnesium hydroxide (1) to (1).
The insulating resin composition according to any one of (7). (9) The insulating resin composition according to any one of (1) to (8), wherein the double oxide of the flame retardant aid contains a molybdenum element or a titanium element. (10) Zinc molybdate, calcium molybdate, calcium zinc molybdate,
(1) to (9), which are zinc titanate, calcium titanate, or a compound containing them.
The insulating resin composition according to any one of the above. (11) An insulating material with a copper foil, wherein the insulating resin composition according to any one of (1) to (10) is provided on a roughened surface of a copper foil having at least one roughened surface. (12) An insulating material with double-sided copper foil, obtained by laminating and molding the insulating material side of the insulating material with copper foil according to (11). (13) A metal-clad laminate formed by laminating at least one or more prepreg or core material on one side or both sides with an insulating material layer side of an insulating material with a copper foil and press-molding the same. A copper-clad laminate using the insulating material with a copper foil described in (1).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The epoxy resin used in the present invention may be any compound as long as it is a compound having two or more epoxy groups in a molecule. For example, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, There are aliphatic chain epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, epoxidized polybutadiene, glycidyl ester type epoxy resin, glycidylamine type epoxy resin and the like. A bisphenol-type epoxy resin or a novolak-type epoxy resin is preferably used, and a mixture of a bisphenol-A-type epoxy resin and a novolak-type epoxy resin such as a cresol novolak-type epoxy resin is particularly preferable for improving the filling property of the inner layer circuit and the heat resistance. These epoxy resins may have any molecular weight, and two or more kinds may be used in combination.

The epoxy resin curing agent used in the present invention may be any one as long as it is usually used as a curing agent for an epoxy resin. For example, amines such as diethylaminopropylamine, and polycondensation of a polyamine and a polymerized fatty acid may be used. Various polyamide-based curing agents such as polyamide resins, acid anhydrides such as phthalic anhydride and trimellitic anhydride, basic active hydrogen compounds such as dicyandiamide, and phenolic hydroxyl groups in one molecule. Compounds such as bisphenol A, bisphenol F, bisphenol S, etc., and phenol resins such as phenol novolak resin, bisphenol novolak resin, and melamine-modified phenol novolak resins such as phenols and compounds having a triazine ring and aldehydes Reactants It is. Some of these compounds can be used in combination. Dicyandiamide, melamine-modified phenol novolak resin, and the like are preferable because they have a high nitrogen element content and improve flame retardancy.

The ratio of the epoxy resin curing agent to the epoxy resin is 2 to 100 parts by weight of the epoxy resin.
When the amount of the epoxy resin curing agent is less than 2 parts by weight, the curing of the epoxy resin tends to be insufficient and the heat resistance tends to decrease. When the amount is more than 100 parts by weight, the curing agent is Since it becomes excessive and functions as a plasticizer, the heat resistance also tends to decrease.

It is preferable that the resin composition of the present invention contains an epoxy resin curing accelerator. The curing accelerator may be any as long as it promotes a usual curing reaction of an epoxy resin, and examples thereof include imidazoles, organic phosphorus compounds, tertiary amines, and quaternary ammonium salts.
Examples of imidazoles include imidazole, 1-methylimidazole, 2-methylimidazole, 4-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole,
-Benzyl-2-methylimidazole, 4-phenylimidazole, benzimidazole, 1-cyanoethyl-
2-methylimidazole and the like; organic phosphorus compounds such as triphenylphosphine; tertiary amines such as triethylamine, tributylamine and pyridine; and quaternary ammonium salts such as tetrabutylammonium acetate and tetrahydrogen sulfate. Butylammonium and the like. The ratio of the curing accelerator to the epoxy resin is 0.01 to 100 parts by weight of the epoxy resin.
A range of 10 parts by weight is preferred. When the amount of the curing accelerator is less than 0.01 part by weight, the curing of the epoxy resin tends to be insufficient and the heat resistance tends to decrease. When the amount is more than 10 parts by weight, the curing accelerator becomes excessive and the heat resistance is reduced. Tends to decrease. Many compounds having a nitrogen element correspond to the curing accelerator, and these are effective for flame retardation.

The resin composition of the present invention may optionally contain a compound containing a phosphorus element or a silane coupling agent as an additive.

The total amount of the nitrogen element contained in these compounds is 0.1 to 10% by weight based on the total amount of the epoxy resin, the epoxy resin curing agent, the curing accelerator and the additives used as required. It is preferred that In order to make the resin composition in the present invention flame-retardant, nitrogen element is added at 0.1
It is preferable that the content is not less than 10% by weight, and if it exceeds 10% by weight, heat resistance tends to decrease. Further, the resin composition of the present invention contains 0.1 to 10% by weight of a phosphorus element with respect to the total amount of the epoxy resin, the epoxy resin curing agent, the curing accelerator optionally used, and the additives. It is preferred that In order to enhance the flame retardancy, it is preferable that the phosphorus element is contained in an amount of 0.1% by weight or more. In order to introduce the phosphorus element, an additive containing a phosphorus element such as a phosphate compound may be added, or a phosphorus element-containing epoxy resin or an epoxy resin curing agent containing a phosphorus element may be used. .
It is preferable to add a phosphate compound as an additive, since phosphorus element can be introduced without deteriorating other properties. Examples of the phosphate compound include CR-7
33s, CR-741, CR-747, PX-200
(All trade names manufactured by Daihachi Chemical Industry Co., Ltd.) are commercially available, and can be used.

The electrically insulating whiskers used in the present invention preferably have an elastic modulus of 200 GPa or more.
When the elastic modulus is less than 200 GPa, there is a tendency that sufficient rigidity cannot be obtained when a multilayer printed wiring board is formed. As such an electrically insulating whisker, an electrically insulating ceramic whisker is preferably used.

Examples of whiskers include aluminum borate, magnesium borate, wollastonite,
One or more selected from potassium titanate, basic magnesium sulfate, silicon nitride, and α-alumina can be used. Among them, aluminum borate whiskers and magnesium borate whiskers are preferable because they have a flame retardant effect. The average diameter of the whiskers is 0.1-
3.0 μm is preferred. If it is less than 0.1 μm, the rigidity tends to decrease. If it exceeds 3.0 μm, the surface smoothness tends to be adversely affected, and the microscopic uniform dispersion of whiskers may be impaired. The average diameter is particularly preferably 1.0 μm or less because of good coatability (easy to apply smoothly).

The average length of the whiskers is preferably at least 10 times the average diameter. If the ratio is less than 10 times, the reinforcing effect as a fiber tends to decrease, and the rigidity of the wiring board may be insufficient. For this reason, it is particularly preferred that the average length of the whiskers is at least about 20 times the average diameter. However, if the whiskers are too long, uniform dispersion in the varnish becomes difficult and the coating properties tend to decrease, and the whiskers in contact with one conductor circuit come into contact with another conductor circuit. The average length of the whiskers is preferably 100 μm or less, particularly preferably 50 μm or less, because the probability increases and a short circuit between circuits may occur due to migration of copper ions that tend to move along the fiber.

As the metal hydroxide used in the present invention, a hydroxide of a metal other than an alkali metal is preferably used.
Aluminum hydroxide or magnesium hydroxide is particularly preferred because of its high flame retardant effect. These metal hydroxides may be used alone or in combination of two or more.

In order to further increase the rigidity and heat resistance of the printed wiring board, it is effective to use whiskers and metal hydroxides surface-treated with a coupling agent.
If surface treatment with a coupling agent, wettability with resin,
It has excellent bondability and can improve rigidity and heat resistance. As the coupling agent used at this time, known compounds such as silicon-based, titanium-based, aluminum-based, zirconium-based, zirconaluminum-based, chromium-based, boron-based, phosphorus-based, and amino acid-based can be used.

The compounding amount of the electrically insulating whisker and the metal hydroxide may be in any range, but the electrically insulating whisker is 5 to 45% by volume of the solid content of the resin composition,
The content of the metal hydroxide is preferably 5 to 45% by volume, and the total is preferably 10 to 50% by volume. When the amount of the electrically insulating whisker or metal hydroxide is less than 5% by volume, sufficient rigidity tends not to be obtained when the printed wiring board is used. On the other hand, if the total amount exceeds 50% by volume, the adhesiveness to the inner layer board of the multilayer printed board and the resin filling property between the inner layer circuits tend to decrease.

The composite oxide of the flame retardant aid used in the present invention includes:
Molybdate compounds, titanate compounds, and the like,
For example, zinc molybdate, calcium molybdate,
Examples include calcium zinc molybdate, zinc titanate, calcium titanate, and mixtures of these substances with fillers such as silica, calcium carbonate, and magnesium silicate. These double oxides of the flame retardant aid may be used alone or in combination of two or more. The ratio of the composite oxide of the flame retardant aid to the resin composition is preferably in the range of 0.001 to 10 parts by weight based on 100 parts by weight of the epoxy resin. When the composite oxide of the flame retardant aid is less than 0.001 part by weight,
Flame retardancy is reduced, there is a possibility of burning, and if it is more than 10 parts by weight, adhesion to copper tends to be reduced.

In order to mix the insulating resin for a printed wiring board of the present invention, it is preferable to add a solvent. The solvent may be any one that dissolves the composition comprising the epoxy resin, the epoxy resin curing agent and the curing accelerator used as necessary, and particularly acetone, methyl ethyl ketone, methyl butyl ketone, and toluene. , Xylene,
Ethyl acetate, N, N-dimethylformamide, N, N-dimethylacetamide, ethanol, ethylene glycol monomethyl ether, and the like are preferable because of their excellent solubility of epoxy resin and relatively low boiling point. Solvents may be used in combination of two or more. The compounding amount of these solvents may be any amount as long as the epoxy resin is dissolved and the electrically insulating whisker, metal hydroxide, and double oxide of the flame retardant aid can be mixed. for,
The range is preferably from 5 to 300 parts by weight, more preferably from 30 to 200 parts by weight. If the solvent is less than 5 parts by weight, the viscosity tends to be high, and it tends to be difficult to mix uniformly, and if it exceeds 300 parts by weight, the viscosity is too low, so that it is difficult to form a thick coating film. Tend.

In order to uniformly disperse the electrically insulating whisker, the metal hydroxide, and the double oxide of the flame retardant aid, it is effective to use a grinder, a homogenizer or the like.

The insulating resin composition of the present invention can be laminated on a copper foil to form an insulating material with a copper foil. This insulating material with a copper foil can be produced, for example, by applying the above-mentioned insulating resin composition to a copper foil.

As the copper foil, there can be used an electrolytic copper foil, a rolled copper foil, and an ultra-thin copper foil with a carrier film which are conventionally used for printed wiring boards having a roughened surface on at least one side. The thickness of the copper foil is preferably small, and is preferably 30 μm or less, because a fine circuit can be formed. Particularly preferred is an ultra-thin copper foil having a thickness of 10 μm or less,
In this case, it is preferable to use a copper foil with a carrier film because handling by itself is difficult.

When the above insulating resin composition is laminated on a smooth copper foil surface to produce an insulating material with a copper foil, it tends to be difficult to ensure sufficient adhesion between the copper foil and the insulating resin composition. There is. Therefore, the copper foil preferably has one surface roughened. It is preferable that an insulating resin composition is laminated on the roughened surface to produce an insulating material with a copper foil.

The thickness of the insulating resin composition is from 20 to 150 μm.
m is preferred. When applying the insulating resin composition varnish to a copper foil, a shear force is applied in a plane direction parallel to the copper foil such as a blade coater, a rod coater, a knife coater, a squeeze coater, a reverse roll coater, and a transfer roll coater. Alternatively, a coating method capable of applying a compressive force in a direction perpendicular to the surface of the copper foil may be adopted. The drying temperature is preferably from 80 to 200C. The drying time may be a time that does not cause excessive curing, and is preferably 1 minute or more. When the drying temperature is lower than 80 ° C. or when the drying time is shorter than 1 minute, the curing is insufficient, and the handleability tends to deteriorate. If the temperature is 200 ° C. or higher, curing tends to proceed too much.

Further, a prepreg or a core material may be laminated on one side or both sides on the insulating resin surface of the insulating material with copper foil, and then thermocompression-bonded to form a metal-clad laminate. Examples of the thermocompression bonding method include a hot press method and a hot roll laminating method. For example, under vacuum or normal pressure, the temperature is 80 to 200.
Molding can be carried out at a temperature of 0.1 ° C. and a pressure of 0.1 to 15 MPa for 0.1 to 120 minutes. Examples of the base material of the prepreg or the core material used here include paper, glass cloth, aramid cloth or respective nonwoven fabrics, and the thermosetting resin used for the matrix includes a phenol resin, an epoxy resin, and a polyimide resin. .

The insulating resin composition of the present invention may be formed by laminating the insulating resin surface side of the insulating material with copper foil on the insulating resin surface side to form an insulating resin with double-sided copper. Further, the insulating resin composition of the present invention may be formed by laminating the insulating resin surface side of the insulating material with copper foil on the inner layer board to form a multilayer copper-clad laminate, which is processed into a multilayer printed wiring board. You. Further, the insulating resin composition of the present invention may be impregnated into a base material such as a paper base material or a fiber base material such as glass fiber to form a B-stage into a prepreg, and a fiber such as a paper base material or glass fiber. After impregnating a base material such as a base material, a copper foil is laminated on one or both surfaces of the prepreg to form a B-stage, and a prepreg with a copper foil may be formed. An adhesive with foil may be used. The adhesive with copper foil may be laminated on the inner layer board on the adhesive side to form a laminate for a multilayer wiring board. This is processed into a multilayer printed wiring board.

[0030]

The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples.

Example 1 100 parts by weight of bisphenol A novolak type epoxy resin (epoxy equivalent: 205), 7 parts by weight of dicyandiamide, 1 part by weight of 1-methylimidazole, whisker of aluminum borate (average diameter 0.9 μm, average length 30 μm)
m) 40 parts by weight (11% by volume in solids), 40 parts by weight of aluminum hydroxide (14% by volume in solids), 1 part by weight of calcium zinc molybdate, 1 part by weight of calcium titanate and 100 parts by weight of methyl ethyl ketone are weighed. Then, the mixture was stirred to obtain a varnish. In addition, the volume% was obtained by calculating the volume of each material from the weight and density and using this. The ratio of the nitrogen element in the total resin of the epoxy resin, the epoxy resin curing agent and the curing accelerator is 4.4% by weight, and the ratio of the phosphorus element is 0.0% by weight. This varnish is applied on a roughened surface of an electrolytic copper foil having a thickness of 18 μm with a knife coater so that the thickness of the insulating resin after drying becomes 50 μm, and dried at 140 ° C. for 3 minutes to obtain a semi-cured insulation with copper foil. Wood was obtained. The insulating material with the copper foil was laminated on the insulating resin side, and heated and pressed at 170 ° C., 2 MPa for 1 hour using a press to obtain a cured double-sided copper-coated insulating resin.

The obtained double-sided copper-laminated insulating resin cured product 2
The solder heat resistance at 88 ° C. is good without swelling or the like for 300 seconds or more, and the cured insulating resin obtained by peeling copper by etching has a maximum burning time of 7 seconds in a burning test and an average burning time of 4 seconds. It showed flammability. Further, if the thickness of the insulating layer is 0.1
mm, the thickness of the copper foil for conductors is 18 μm. The obtained insulating material with copper foil is applied to both sides of the inner layer circuit board prepared by removing unnecessary portions of copper foil on both sides of the double-sided copper-clad laminate by etching. Overlap so that the insulating resin side faces the inner layer circuit, and press and heat at 170 ° C., 2 MPa, 1 hour using a press,
A multilayer copper-clad laminate containing an inner layer circuit was obtained. As a result of removing the copper foil of this laminated plate by etching and visually observing, there was no defect such as void or blur.

Example 2 100 parts by weight of o-cresol novolak type epoxy resin (epoxy equivalent: 215), 40 parts by weight of melamine-modified phenol novolak resin (phenolic hydroxyl equivalent: 120, nitrogen atom content: 8% by weight), 1-methylimidazole 1 part by weight, magnesium borate whisker (average diameter 1.
0 μm, average length 30 μm) 100 parts by weight (1 in solid content)
9% by volume), 50 parts by weight of magnesium hydroxide (11% by volume in solid content), 0.1 part by weight of calcium molybdate, PX-200 (trade name of Daihachi Chemical Industry Co., Ltd.) as a phosphate compound 15 A weight part and 200 weight parts of methyl ethyl ketone were weighed and stirred to obtain a varnish. The total ratio of the nitrogen element in the total resin of the epoxy resin, the epoxy resin curing agent, the curing accelerator and the phosphate ester is 2.3.
The percentage by weight of phosphorus element was 1.0% by weight. This varnish is applied on a roughened surface of an electrolytic copper foil having a thickness of 18 μm with a knife coater so that the thickness of the insulating resin after drying becomes 50 μm, and dried at 140 ° C. for 3 minutes to obtain a semi-cured insulation with copper foil. Wood was obtained. The insulating material with the copper foil was laminated on the insulating resin side, and heated and pressed at 170 ° C., 2 MPa for 1 hour using a press to obtain a cured double-sided copper-coated insulating resin.

The obtained double-sided copper-clad insulating resin cured product 2
The solder heat resistance at 88 ° C. is good without causing swelling or the like for 180 seconds or more. The cured insulating resin obtained by peeling copper by etching has a maximum burning time of 3 seconds in a burning test and an average burning time of 1.2 seconds. Showed flame retardancy. In addition, the unnecessary portions of the copper foil on both sides of the double-sided copper-clad laminate having the thickness of the insulating layer of 0.1 mm and the thickness of the copper foil for the conductor of 18 μm were removed by etching on both sides of the inner circuit board. The obtained insulating material with copper foil was overlaid so that the insulating resin side faced the inner layer circuit, and heated and pressed at 170 ° C., 4 MPa for 1 hour using a press to obtain a multilayer copper-clad laminate containing the inner layer circuit. As a result of removing the copper foil of this laminated plate by etching and visually observing, there was no defect such as void or blur.

Example 3 Salicylaldehyde phenol novolak type epoxy resin (epoxy equivalent: 172) 100 parts by weight, phenol novolak resin (phenolic hydroxyl group equivalent: 108) 60 parts by weight, 1-methylimidazole 1 part by weight, aluminum borate whisker (average diameter) 0.9 μm, average length 30 μ
m) 150 parts by weight (25% by volume in solids), 50 parts by weight of aluminum hydroxide (10% by volume in solids), 8 parts by weight of a zinc molybdate-magnesium silicate composite, and 200 parts by weight of methyl ethyl ketone were weighed and stirred. To obtain a varnish. Epoxy resin, epoxy resin curing agent and the proportion of nitrogen and phosphorus elements in the total resin of the total of the curing accelerator,
It was 0.0% by weight. This varnish is applied on a roughened surface of an electrolytic copper foil having a thickness of 18 μm with a knife coater so that the thickness of the insulating resin after drying becomes 50 μm, and dried at 140 ° C. for 3 minutes to obtain a semi-cured insulation with copper foil. Wood was obtained. The insulating material with copper foil was laminated on the insulating resin side, and heated and pressed at 170 ° C., 4 MPa, for 1 hour using a press to obtain a double-sided copper-clad insulating resin cured product.

The obtained double-sided copper-laminated insulating resin cured product 2
The solder heat resistance at 88 ° C. is good without swelling or the like for 300 seconds or more, and the cured insulating resin obtained by peeling copper by etching has a maximum burning time of 4 seconds in a burning test and an average burning time of 1.3 seconds. Showed flame retardancy. In addition, the unnecessary portions of the copper foil on both sides of the double-sided copper-clad laminate having the thickness of the insulating layer of 0.1 mm and the thickness of the copper foil for the conductor of 18 μm were removed by etching on both sides of the inner circuit board. The obtained insulating material with copper foil was overlaid so that the insulating resin side faced the inner layer circuit, and heated and pressed at 170 ° C., 4 MPa for 1 hour using a press to obtain a multilayer copper-clad laminate containing the inner layer circuit. The lamination of the laminate was removed by etching and visually observed. As a result, no defects such as voids and blurring were found.

Example 4 Salicylaldehyde phenol novolak type epoxy resin (epoxy equivalent: 172) 100 parts by weight, phenol novolak resin (phenolic hydroxyl group equivalent: 108) 60 parts by weight, 1-methylimidazole 1 part by weight, aluminum borate whisker (average diameter) 0.9 μm, average length 30 μ
m) 150 parts by weight, 50 parts by weight of aluminum hydroxide, -1 part by weight of zinc titanate, and 200 parts by weight of methyl ethyl ketone were weighed and stirred to obtain a varnish. In the resin composition obtained by removing methyl ethyl ketone from the varnish, aluminum borate whiskers accounted for 25% by volume, magnesium hydroxide accounted for 10% by volume, and the total nitrogen content of the epoxy resin, epoxy resin curing agent and curing accelerator in the total resin The ratio of the element and the phosphorus element was 0.0% by weight. This varnish was applied on a roughened surface of an electrolytic copper foil having a thickness of 18 μm with a knife coater so that the thickness of the insulating resin after drying became 50 μm.
After drying at 0 ° C. for 3 minutes, a semi-cured insulating material with copper foil was obtained. Lay this insulating material with copper foil on the insulating resin side,
The mixture was heated and pressed at 170 ° C. and 4 MPa for 1 hour using a press to obtain a double-sided copper-clad insulating resin cured product.

The obtained double-sided copper-clad insulating resin cured product 2
The solder heat resistance at 88 ° C. is good without swelling or the like for 300 seconds or more, and the cured insulating resin obtained by peeling copper by etching has a maximum burning time of 6 seconds in a burning test, and an average burning time of 2.8 seconds. Showed flame retardancy. In addition, the unnecessary portions of the copper foil on both sides of the double-sided copper-clad laminate having the thickness of the insulating layer of 0.1 mm and the thickness of the copper foil for the conductor of 18 μm were removed by etching on both sides of the inner circuit board. The obtained insulating material with copper foil was overlaid so that the insulating resin side faced the inner layer circuit, and heated and pressed at 170 ° C., 4 MPa for 1 hour using a press to obtain a multilayer copper-clad laminate containing the inner layer circuit. As a result of removing the copper foil of this laminated plate by etching and visually observing, there was no defect such as void or blur.

Comparative Example 1 A double-sided copper-clad insulating resin cured product prepared in the same manner as in Example 3 except that no molybdate compound was added was used.
At a soldering heat resistance of 88 ° C., swelling or the like did not occur for 300 seconds or more, but it was good. The ratio of the nitrogen element and the phosphorus element in the total resin of the epoxy resin, the epoxy resin curing agent, and the curing accelerator is 0.0% by weight. In addition, the unnecessary portions of the copper foil on both sides of the double-sided copper-clad laminate having the thickness of the insulating layer of 0.1 mm and the thickness of the copper foil for the conductor of 18 μm were removed by etching on both sides of the inner circuit board. Then, the obtained insulating material with copper foil is overlapped so that the insulating resin side faces the inner layer circuit, and 170 is pressed using a press.
C., 4 MPa, 1 hour under heating and pressure to obtain a multilayer copper-clad laminate with an inner circuit. As a result of removing the copper foil of this laminated plate by etching and visually observing, there was no defect such as void or blur.

[0040]

The insulating resin composition according to the present invention can be made flame-retardant without using a halogen-based flame retardant, and a non-halogen-based insulating material with a flame-retardant copper foil can be produced. Moreover, they are excellent in heat resistance and reliability. By using this insulating resin composition, it is possible to produce an insulating material with a copper foil and a copper-clad laminate excellent in flame retardancy, heat resistance and reliability, and capable of meeting the demands for environmental protection.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 3/38 C08K 3/38 5/521 5/521 H01B 3/40 H01B 3/40 CGPF term (Ref.) AF22 AF27 AG04 AH01 DA01 DB06 DC31 FA02 FA06 FA12 FB08 JA08 KA01 5G305 AA06 AA11 AA12 AB24 AB25 AB35 BA09 BA25 CA15 CB17 CB23 CB28 CC03 CC11 CD08 CD13

Claims (13)

[Claims] 1. An insulating resin composition comprising, as essential components, an epoxy resin, an epoxy resin curing agent, an electrically insulating whisker, a metal hydroxide and a double oxide of a flame retardant auxiliary. 2. The total amount of nitrogen elements contained in these compounds with respect to the total amount of the epoxy resin, the epoxy resin curing agent, the curing accelerator optionally used and the additive optionally used. The insulating resin composition according to claim 1, wherein the amount is 0.5% by weight or more. 3. The insulating resin composition according to claim 1, wherein the epoxy resin curing agent is a dicyandiamide or melamine-modified phenol novolak resin. 4. The total amount of the phosphorus element is 0.1% by weight based on the total amount of the epoxy resin, the epoxy resin curing agent, the curing accelerator optionally used, and the additive optionally used. % Of the insulating resin composition according to claim 1. 5. The insulating resin composition according to claim 1, further comprising a phosphate compound as a component of the resin composition. 6. The method according to claim 1, wherein the total of the electrically insulating whiskers and the metal hydroxide is 10% by volume or more.
6. The insulating resin composition according to any one of items 1 to 5. 7. The insulating resin composition according to claim 1, wherein the electrically insulating whisker is aluminum borate and / or magnesium borate. 8. The insulating resin composition according to claim 1, wherein the metal hydroxide is aluminum hydroxide and / or magnesium hydroxide. 9. The insulating resin composition according to claim 1, wherein the double oxide of the flame retardant aid contains a molybdenum element or a titanium element. 10. The multi-oxide of the flame retardant aid is zinc molybdate, calcium molybdate, calcium zinc molybdate, zinc titanate, calcium titanate, or a compound containing these. 1
10. The insulating resin composition according to any one of items 1 to 9. 11. An insulating material with a copper foil, wherein the insulating resin composition according to any one of claims 1 to 10 is provided on a roughened surface of a copper foil having at least one roughened surface. 12. An insulating material with a double-sided copper foil obtained by laminating and molding the insulating material side of the insulating material with a copper foil according to claim 11. 13. A metal-clad laminate obtained by laminating at least one or more prepregs or core materials on one or both sides with an insulating material layer side of an insulating material with a copper foil, and press-molding the same. A copper-clad laminate using the insulating material with a copper foil according to claim 11.