JP5423602B2 - Low dielectric constant insulating resin composition - Google Patents

Description

  The present invention is a low dielectric constant insulating resin composition, an insulating resin varnish, a prepreg, an insulating resin film, a laminate, and a low dielectric constant, which are also excellent in characteristics such as heat resistance, glass transition temperature, and peel strength. The present invention relates to a multilayer wiring board.

  In recent years, communication devices included in computers and information device terminals have been required to increase the amount of data transmission in order to process a large amount of data at high speed. As part of this, the frequency of electrical signals is increasing. However, when high frequency components increase in the electrical signal, the signal waveform is distorted due to the delay in the transmission path, the strength is easily attenuated, the loss in the transmission path increases, the reflection of the signal increases, the transmission path There is a problem that unnecessary radiation increases. Therefore, in order to promote full-fledged use of the high frequency band, the impedance is controlled in a wide band, for example, the dielectric property of the printed wiring board substrate material is controlled, for example, the dielectric constant is lowered (lower dielectric constant). It is necessary to reduce loss and reflection. Therefore, a printed circuit board material having a low dielectric constant capable of processing electrical signals at high speed with low transmission loss is desired. In addition, it is important for practical use to have characteristics such as heat resistance (including glass transition temperature and dimensional stability against heat), adhesion, and mechanical strength (for example, peel strength) in addition to dielectric properties. is there.

  Low dielectric constant is achieved by, for example, mixing an insulating resin composition with a low dielectric constant agent that is a substance different from the insulating resin composition for the purpose of reducing the relative dielectric constant of the insulating resin composition. The mixing ratio was controlled to adjust the relative dielectric constant of the obtained low dielectric constant insulating resin composition. The mixing method to the insulating resin composition is the contact mixing in which the low dielectric constant agent and the resin (insulating resin composition) are in direct contact, or the surface of the low dielectric constant agent is resin (insulating resin composition). It was non-contact mixing in which a low dielectric constant agent coated with a material inert to the resin was indirectly contacted with a resin (insulating resin composition). Examples of the contact mixing method include a method of uniformly dissolving a low dielectric constant agent in a resin (insulating resin composition), a method of dispersing and mixing the low dielectric constant agent in a resin (insulating resin composition), and the like. However, these methods can adjust the required dielectric constant, but have a problem that characteristics such as heat resistance, glass transition temperature, and peel strength are deteriorated. For example, in the case of uniform dissolution (compatibility), in addition to heat resistance in terms of chemical properties such as lowering or increasing the reaction rate (for example, curing rate) of the insulating resin composition, it becomes difficult to control the reaction. Various properties predicted from the insulating resin composition itself are reduced in terms of physical properties such as adhesiveness (including glass transition temperature, dimensional stability against heat, etc.), adhesion, and mechanical strength (for example, peel strength). To do. For this reason, when a low dielectric constant agent is contact-mixed with the insulating resin composition, there is a problem that not all desired performance can be obtained. There was a similar problem in the case of particle dispersion (Patent Document 1).

In addition, when non-contact mixing is performed with the insulating resin composition, a method of mixing the resin (insulating resin composition) and the hollow material, and mixing the foaming agent with the resin (insulating resin composition) for insulation A method of providing voids in the cured product of the conductive resin composition (void arrangement), a method of coating the low dielectric constant agent on the resin (insulating resin composition) with an inert coating material and mixing (coating mixing) (Patent Documents 2 and 3). However, there is a problem in terms of mechanical strength in the case of the gap arrangement. In the case of coating mixing, the resin (insulating resin composition) coating material has poor dispersibility to the resin and is difficult to homogenize, and the ceramic coating material has insufficient mechanical strength. There was a problem that it was difficult to process the insulating resin composition.
Therefore, there is a need for a low dielectric constant agent for resins that can adjust only specific characteristics of the insulating resin composition and that does not adversely affect the performance of characteristics such as heat resistance, glass transition temperature, and peel strength. .

Japanese Patent Publication No. 2004-513503 JP-A-8-253625 JP-A-6-62346

  An object of the present invention is to provide a low dielectric constant insulating resin composition which has a low dielectric constant and excellent properties such as heat resistance, glass transition temperature and peel strength.

As a result of intensive studies to solve the above problems, the present inventors have reached the present invention.
The present invention is a low dielectric constant insulating resin composition comprising an insulating resin composition and a low dielectric constant agent,
The low dielectric constant agent is composed of a porous material and a low dielectric constant component embedded in the porous material, and the dielectric constant of the low dielectric constant component in the low dielectric constant agent is And an insulating resin composition having a low dielectric constant smaller than the dielectric constant of the insulating resin composition (Invention 1).
Here, “embedded” means that a low dielectric constant component exists in the porous material, but even if the low dielectric constant component and the insulating resin composition are in contact with each other, other than the dielectric constant, It does not adversely affect properties such as heat resistance, glass transition temperature and peel strength (a state in which interaction is avoided). For example, the area of each contact portion between the low dielectric constant component and the insulating resin composition is a contact area that avoids the interaction between the low dielectric constant component and the insulating resin composition. The contact area can be calculated from the pore diameter of the porous material, and the average pore diameter on the surface of the porous material is preferably 1 to 1000 nm.

  The present invention achieves a low dielectric constant insulating resin composition having a low dielectric constant and excellent properties such as heat resistance, glass transition temperature and peel strength.

FIG. 1 is a cross-sectional observation SEM photograph of filled porous silica of the present invention and unfilled porous silica.

  According to the present invention, the low dielectric constant agent is configured by filling the low dielectric constant component in the porous material and immobilizing it in order to embed the low dielectric constant component in the porous material. Low dielectric constant agent (porous material) The dielectric constant of the low dielectric constant insulating resin composition is in contact with the insulating resin composition outside the area in order to avoid interaction with the low dielectric constant component. Performance of other characteristics (heat resistance (including glass transition temperature, dimensional stability against heat, etc.), adhesiveness, mechanical strength (for example, peel strength)) with low dielectric constant insulating resin composition Is maintained.

  Here, composites in which pores of a porous material are filled with other materials are known (Patent Documents 2 and 3). Patent Document 2 discloses a water-repellent powder that is made water-repellent by filling a porous silica with a silicone cured product. Patent Document 3 discloses a separation / adsorbent such as a chromatogram in which porous silica is filled with an ion exchange resin / chelate resin to increase the surface area of the composite. All of these are made to contact the target substance (water or metal, etc.) with the active substance (silicone cured product or ion exchange resin / chelate resin) intervened on the surface or inside of the porous substance, and act on the target substance. The purpose is to affect. Therefore, as in the present invention, an active substance (low dielectric constant component) is embedded in a porous substance, and contact is made so as to avoid an unwanted interaction with the target substance (insulating resin composition). Are different in structure, action and function.

  The material of the porous material of the present invention is not limited as long as the material has pores and is inert to the resin. In addition to the independent pores, it is preferable that the pores lead to the outside of the porous material and are associated with each other. The material of the porous material is, for example, silica, silica gel, glass, alumina, zeolite, metal hydroxide such as aluminum hydroxide, diatomaceous earth, silicate such as calcium silicate, phosphate such as calcium phosphate, calcium carbonate, etc. Examples thereof include carbonate, activated carbon, acrylic resin, polyimide resin, urethane resin, chitosan resin, polysiloxane resin, silicone rubber, and cellulose acetate resin. The porous material is preferably an inorganic porous material, and more preferably porous silica.

  Further, the shape of the porous material of the present invention is not particularly limited. For example, spherical shape, scale shape, needle shape, amorphous powder shape, plate shape, honeycomb shape and the like can be mentioned. A spherical shape is preferable because the fluidity of the resin can be controlled. The average pore diameter on the surface is preferably 1 to 1000 nm, more preferably 1 to 100 nm, and more preferably 1 to 50 nm. When the average pore diameter on the surface is 1 nm or more, filling of the low dielectric constant component is easy, and when it is 1000 nm or less, the contact area is such that interaction between the low dielectric constant component and the resin is avoided.

The average particle size of the porous material of the present invention is preferably 0.05 to 100 μm, and more preferably 0.1 to 10 μm. The filling amount of the dielectric constant-reducing component into the porous material is preferably from pore volume to less than 100% by volume, considering that it does not exist on the surface of the porous material. As for the filling amount, the higher the filling of the low dielectric constant component, the higher the mechanical strength of the porous material. Further, if a large amount of air having a low dielectric constant of 1 is present in the porous material, for example, in the independent pores, the dielectric constant of the porous material itself is lowered, and the low dielectric constant agent has a high effect of reducing the dielectric constant. Become. When the filling amount of the low dielectric constant component is less than 100% by volume of the pore volume, the low dielectric constant component is embedded in the pores of the porous material and does not exist on the surface of the porous material. The pore volume is preferably 10 to 700 ml / 100 g, more preferably 50 to 500 ml / 100 g in terms of oil absorption by the JIS K 5101-13-1 refined linseed oil method. When the oil absorption is 10 ml / 100 g or more, the effect of adjusting the dielectric constant is significant, and when it is 700 ml / 100 g or less, the strength of the porous material is sufficient. The pore volume in the present invention is the volume of pores communicating with the outside of the porous material, and does not include the volume of independent pores.
As the porous substance of the present invention, two or more kinds of porous substances having different materials, shapes, average pore diameters, oil absorptions, and average particle diameters can be used.

The low dielectric constant component embedded in the porous material in the present invention is not particularly limited as long as the dielectric constant is lower than that of the insulating resin composition outside the porous material. In consideration of lowering the dielectric constant, the dielectric constant is preferably 0.2 or more lower than that of the insulating resin composition .

In order to suppress dissolution of the low dielectric constant component in the insulating resin composition, the low dielectric constant component is preferably solid at 20 ° C. or higher, and more preferably solid at 23 ° C. or higher. In addition, it is preferably insoluble in the solvent of the insulating resin composition.
In consideration of handleability when embedding in a porous material, the low dielectric constant component preferably has fluidity by pressurization or heating, that is, has fluidity without using a solvent. This is because if the fluidity is obtained using a volatile substance such as a solvent, the solvent may volatilize during heating / drying or storage, so when considering the fixation and filling control of the low dielectric constant component It is preferable not to use a solvent .

When obtaining fluidity by heating, the temperature of the pour point or melting point is preferably in the temperature range in which the mechanical strength of the porous material is maintained. Considering the production environment and the like, the melting point is preferably 100 to 200 ° C.
The viscosity above the pour point is preferably 10,000 poise (1 kPa · s) or less.

  Low dielectric constant components include, for example, polyolefins such as polyethylene and polypropylene, polypropylene ether, polyamide, polyamideimide, polyarylate, thermoplastic polyimide, polyetheretherketone, polyethylene oxide, polyethylene terephthalate, polyvinylidene chloride, and polychlorinated chloride. Thermoplastic resin such as vinyl, polycarbonate, polyvinyl acetate, polystyrene, polybutadiene, polyvinyl ether, epoxy resin, xylene resin, guanamine resin, diallyl phthalate resin, unsaturated polyester resin, phenol resin, unsaturated polyester resin, polyimide, polyurethane, Examples thereof include thermosetting resins such as maleic resin, melamine resin and urea resin, and photosensitive resins such as epoxy acrylate.

In addition, a single low dielectric constant component can be embedded, or two or more types can be used. The low dielectric constant component is preferably thermosetting. Alternatively, the low dielectric constant component is preferably a phosphate ester or a polyolefin. Examples of the phosphate ester include [(CH ₃ ) ₂ C ₆ H ₃ ] ₂ P (O) OC ₆ H ₄ OP (O) [C ₆ H ₃ (CH ₃ ) ₂ ].

  Within the scope of the object of the present invention, a low dielectric constant component and a component for adjusting characteristics such as heat resistance, glass transition temperature and peel strength (a flame retardant adjusting component, a density adjusting component, a release agent) are included in the porous material. Moldability adjusting component, antistatic component, antibacterial component, deodorizing component, etc.) may be interposed or combined.

  An example of a method for fixing a low dielectric constant component in a porous material according to the present invention is an embedding method. As an embedding method, it is easy to fill using a capillary phenomenon. The filling method is, for example, a method of stirring the liquid low dielectric constant component and the porous material into the pores, or stirring the liquid low dielectric constant component and the porous material under pressure to fill the pores. The method of filling in the pores, the method of charging the porous material into the liquid low dielectric constant component after reducing the pressure, stirring and filling the pores, the porous material and the low dielectric constant component are mixed in advance and heated The method of dissolving the low dielectric constant component and filling it in the pores by mixing the porous material and the low dielectric constant component in advance, reducing the pressure and then dissolving the low dielectric constant component by heating A method of filling inside, a method in which a porous material and a low dielectric constant component are mixed in advance, and the low dielectric constant component is dissolved by pressurization and heating to fill the pores, and the low dielectric constant component is a solvent A method of stirring with a porous material and filling the pores with a porous material, etc. The method of removing the solvent by heating after filling the pores with the quality of the material, dissolving the low dielectric constant component with a solvent, etc., stirring with the porous material and filling the pores, and then heating the solvent under reduced pressure The method of removing is mentioned. The porous material filled with the low dielectric constant component can be washed with a solvent or the like in order to remove the low dielectric constant component remaining outside the porous material before being used as a low dielectric constant agent.

Further, according to the present invention, in the method of fixing the low dielectric constant component in the porous material, the oligomer or silane is used to increase the filling property of the low dielectric constant component before filling the low dielectric constant component. it can be processed pore surfaces of the porous material a cup-rings agent.
Lower dielectric constant material filled with low dielectric constant component, in order to enhance the dispersibility, etc. in the oligomer or silane coupling agent or a mixed insulative resin composition, to the surface treatment of filled porous material The particle size can be reduced by performing a treatment such as pulverization.
Thus, when filling a porous material by capillary action or the like, the low dielectric agent is easy to manufacture and inexpensive.

  The insulating resin composition of the present invention is not particularly limited as long as it has electrical insulating properties. For example, heat of thermoplastic resins such as polyethylene, polypropylene, polyamide, polyamideimide, polyarylate, thermoplastic polyimide, polyether ether ketone, polyethylene oxide, polyethylene terephthalate, epoxy resin, polyimide resin, triazine resin, phenol resin, melamine resin, etc. Examples thereof include curable resins and photosensitive resins such as epoxy acrylate. Moreover, even if the insulating resin composition is single, it can use 2 or more types. The insulating resin composition is preferably thermosetting. The insulating resin composition is preferably an epoxy resin.

  In the present invention, a curing agent for the insulating resin composition can be used, and various conventionally known ones can be used. For example, when an epoxy resin is used as the resin, examples thereof include dicyandiamide, diaminodiphenylmethane, diaminodiphenylsulfone, phthalic anhydride, pyromellitic anhydride, polyfunctional phenols such as phenol novolac and cresol novolac. Several kinds of these curing agents can be used in combination. The kind and amount of the accelerator are not particularly limited. For example, an imidazole compound, an organic phosphorus compound, a tertiary amine, a quaternary ammonium salt, or the like is used, and two or more kinds can be used in combination.

  The blending ratio of the low dielectric constant agent of the present invention is preferably 5 to 80% by volume, and particularly preferably 10 to 60% by volume of the insulating resin composition. When the blending ratio of the low dielectric constant agent is 5% by volume or more, the effect of reducing the dielectric constant is significant, and when it is 80% by volume or less, the insulating resin composition is easily handled. Here, the blending ratio was calculated by multiplying the blending amount (weight) by the specific gravity. Specific gravity of insulating resin composition (uncured state) (for example, epoxy resin): 1.2, specific gravity of porous material (for example, porous silica): 2.2, low dielectric component (for example, The specific gravity of the condensed phosphate ester is 1.15.

In order to improve the dispersibility of the low dielectric constant agent in the resin, the kneader, ball mill, bead mill, three rolls, nanomizer and other known kneading methods or the low dielectric constant agent should be pulverized to reduce the particle size. Can do.
Thus, since the low dielectric agent of the present invention exerts its function only by physically mixing with the insulating resin composition, there is no need to change the conventional manufacturing process of the insulating resin composition. Easy to handle.

  The solvent for diluting the insulating resin composition of the present invention is not limited as long as the insulating resin composition can be dissolved. Examples thereof include methyl ethyl ketone, hexane, xylene, toluene, acetone, ethylene glycol monoethyl ether, cyclohexanone, ethyl ethoxypropionate, N, N-dimethylformamide, N, N-dimethylacetamide and the like. These solvents can be used alone or in a mixed system. The ratio of the solvent to the resin is adjusted according to the equipment for applying the insulating resin composition.

  In the insulating resin composition of the present invention, fillers, additives, other reinforcing fiber materials, and the like can be added within the scope of the object of the present invention. For example, examples of the additive include a flame retardant, an antioxidant, a heat stabilizer, an antistatic agent, a plasticizer, a coupling agent, a pigment, a dye, a colorant, and rubber.

When a low dielectric constant insulating resin composition is applied to glass cloth, glass nonwoven fabric, organic woven fabric or organic nonwoven fabric to produce a prepreg, the solid content of the resin excluding the solvent is 20 to 80 weight of the insulating resin varnish. It is preferable to adjust the amount of the solvent used so that it becomes%. When an insulating film is produced by applying a low dielectric constant insulating resin composition to a carrier film or copper foil with a comma coater , the solid content of the resin excluding the solvent is 30 to 60% by weight of the insulating resin varnish. It is preferable to adjust the amount of the solvent used.

  The prepreg using the low dielectric constant insulating resin composition of the present invention can be applied with conventional production methods as it is. That is, the prepreg of the present invention is obtained by impregnating and coating the base material with the low dielectric constant insulating resin composition of the present invention, and the base material is used in various laminates for electrical insulating materials. A well-known thing can be used. Examples of the material of the substrate include inorganic fibers such as E glass, D glass, S glass, and Q glass, organic fibers such as polyimide, polyester, and tetrafluoroethylene, and mixtures thereof. These base materials have, for example, woven fabric, non-woven fabric, low-ink, chopped strand mat, surfacing mat, and the like, and the material and shape are selected depending on the intended use and performance of the molded product, and may be single or 2 as necessary. It can be used from more than a variety of materials and shapes. Although there is no particular limitation on the thickness of the base material, a material with a thickness of about 0.03 to 0.5 mm is usually used, and surface treated with a silane coupling agent or the like or mechanically subjected to fiber opening treatment is heat resistant. And from the viewpoint of moisture resistance and workability. Usually, after the base material is impregnated or coated so that the amount of the low dielectric constant insulating resin composition attached to the base material is 20 to 90% by weight in terms of the resin content of the prepreg after drying, it is usually 100 to 100%. Heat-dry at a temperature of 200 ° C. for 1 to 30 minutes to obtain a semi-cured state (B stage state) prepreg.

A laminate can be produced by laminate molding using the above-described prepreg. Laminate molding can be applied by general methods as it is, for example, usually 1 to 20 prepregs of the present invention are stacked, and a metal foil such as copper or aluminum is arranged on one or both sides by heating and pressing. It can be set as a laminated board by doing. The metal foil is not particularly limited as long as it is used for printed wiring board materials. As the molding conditions, conventional laminates for electrical insulating materials and multilayer boards can be applied. For example, a multi-stage press, a multi-stage vacuum press, continuous molding, an autoclave molding machine, etc. are used. Molding is performed in a range of ˜100 kg / cm ² and a heating time of 0.1 to 5 hours.

  As the support substrate used for the insulating film of the present invention, a metal foil such as copper or aluminum, a resin film such as polyester or polyimide, or a resin film with a release agent applied to the surface thereof can be used. . When copper foil is used for the support substrate, there is an advantage that the copper foil can be used as a circuit conductor as it is, and when the release agent treatment is applied to the support substrate, an insulating film is removed from the support substrate. It is preferable for improving workability when peeling off only the supporting base material after peeling or laminating the film with the supporting base material on the substrate.

  Thus, the insulating film which formed the insulating resin layer in the single side | surface of a support base material can be used for manufacture of a multilayer wiring board by the method shown below. For example, one or a plurality of film-like insulating films from which the supporting base material has been removed are laminated and copper foil is placed on the top and bottom of the film, or press molding is performed, or an insulating resin varnish is applied to the copper foil that is the supporting base material. A laminated board for a multilayer wiring board can be manufactured by laminating the processed insulating films so that the films are combined, and further press-molding with one or more insulating films from which the substrate is removed if necessary. it can.

  The manufacturing method of the multilayer printed wiring board using the prepreg and insulating film of the low dielectric constant insulating resin composition of this invention is demonstrated. First, the low dielectric constant insulating resin composition of the present invention is laminated on a patterned inner layer circuit board. The method includes laminating one or more prepregs and insulating films made of the low dielectric constant insulating resin composition of the present invention, and further placing a copper foil or a circuit-forming substrate on the substrate under pressure and heating conditions. Laminate or press to heat cure. As the circuit formation substrate, a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting PPE substrate, or the like can be used, and the circuit surface can be roughened in advance. The heat curing conditions are a temperature of 120 ° C. or higher, preferably 170 to 220 ° C., and usually 15 to 300 minutes, preferably 60 to 150 minutes.

  After laminating and curing the low dielectric constant insulating resin composition of the present invention on the substrate as described above, drilling and / or laser drilling is performed to form through holes and via holes. As the laser drilling machine, a carbon dioxide laser, a YAG laser, an excimer laser, or the like can be used. Then, after obtaining electrical continuity between the inner layer and the outer layer using techniques such as electroless copper plating, metal vapor deposition, sputtering, ion plating, etc., the laminated book using the circuit forming method in a normal printed wiring board Circuit formation is performed on the surface of the low dielectric constant insulating resin composition of the invention.

  Applications of the low dielectric constant insulating resin composition of the present invention include automobile parts, electronic / electric parts, and the like. Examples of the electronic / electrical component include circuit board laminate materials and semiconductor sealing materials.

  Next, the present invention will be described in more detail with reference to the following examples, but these examples are not intended to limit the present invention in any way.

Preparation of surface treatment agent A solution containing 20 g of dimethoxydimethylsilane, 25 g of tetramethoxysilane and 105 g of methanol was introduced into a glass flask equipped with a stirrer, a condenser and a thermometer, and then 0.60 g of acetic acid and 17.8 g of distilled water. Was added and stirred at 50 ° C. for 8 hours. A siloxane-based surface treating agent having a siloxane unit polymerization degree of 30 was synthesized. The obtained siloxane-based surface treating agent has a methoxy group and a silanol group as terminal functional groups that react with hydroxyl groups.

Example 1
(1) Porous silica 1 as a porous material [oil absorption 150 ml / 100 g (fillable porosity: 76.7%), surface average pore diameter 5-15 nm, specific gravity 2.2, average particle diameter 2. 1 μm, God Ball E-2C (trade name) manufactured by Suzuki Yushi Kogyo Co., Ltd.] and solid condensed phosphate ester [melting point 95 ° C., PX-200 manufactured by Daihachi Chemical Industry Co., Ltd.] as a low dielectric constant component to be filled (Trade name), dielectric constant: 2.8], and 200 parts by weight of porous silica and 600 parts by weight of condensed phosphate ester (PX-200) were equipped with a thermometer, a condenser, a decompressor, and a stirrer. It took in the 4-neck separable flask and pressure-reduced the inside of a 4-neck separable flask, stirring. After confirming that the pressure in the four-neck separable flask has dropped to 10 mmHg (1.3 kPa) or less, heat the four-neck separable flask so that the internal temperature becomes 120 ° C. The porous silica 1 was filled with the condensed phosphate ester which was heated and stirred for a period of time and dissolved to be liquid.

(2) The four-neck separable flask of (1) was cooled to 50 ° C. to solidify the liquid condensed phosphate ester. 1400 parts by weight of methyl ethyl ketone was put into a four-necked separable flask and stirred to dissolve excess solid condensed phosphate ester. After cooling to room temperature by air cooling, suction filtration of the dissolved liquid condensed phosphate ester is performed using a filter having an aperture diameter of 0.45 μm, and the porous silica 1 filled with excess liquid condensed phosphate ester Separated.

(3) Since the porous silica 1 filled in (2) may have a phosphoric acid condensed ester adhering to the surface thereof, the porous silica filled in (2) in 200 parts by weight of methyl ethyl ketone. Silica 1 was added and stirred for 15 minutes to dissolve and remove the surface-attached phosphoric acid condensed ester (cleaning of porous silica). Subsequently, the dissolved phosphoric acid condensed ester was subjected to suction filtration using a filter having a pore size of 0.45 μm to separate the surface-adhered phosphoric acid condensed ester and the porous silica 1 (filled). The process of (3) was repeated again to wash the porous silica 1 (filling). Thereafter, drying is carried out at 50 ° C. for 10 hours, and a low dielectric constant agent 1 (porous silica 1 filled with condensed phosphate ester to approximately 100% by volume of the porous silica pore volume, phosphoric acid condensed ester on the surface) Is not attached). Low dielectric constant agent 1 had a low dielectric constant component content: 76.7%.

In the obtained low dielectric constant agent 1, it was confirmed by microscopic observation of porous silica 1 (filled) and porous silica (unfilled) that the porous silica 1 (filled) was 100% by volume. Sample is made by Hitachi, FB2000A, acceleration voltage 30kV, ion source Ga, cut out any cross section by focused ion beam (FIB) processing (sample after FIB processing), to clean the surface after FIB processing, Ion milling was performed using Hitachi, E3200, and an acceleration voltage of 4 kV (sample after ion milling). In the sample after the ion milling treatment, pores are confirmed in the porous silica (unfilled), but it is clear that the porous silica 1 (filled) is filled without a gap (filled with a pore volume of 100%). . The sample after FIB processing and the sample after ion milling treatment were observed with SEM (manufactured by Hitachi, model number S-4700, acceleration voltage 5.0 kV, magnification: 100,000 times).
FIG. 1 shows cross-sectional observation SEM photographs of the sample after FIB processing and the sample after ion milling for porous silica 1 (filled) and porous silica (unfilled).

(4) The low dielectric constant agent 1 is dispersed in the same weight of methyl ethyl ketone, and the solid content of the surface treatment agent is 1% by weight with respect to the weight of the low dielectric constant agent 1. And heat-treated at the reflux temperature of methyl ethyl ketone for 1 hour to obtain a surface-treated low dielectric constant agent 1.

(5) (4) a low dielectric constant agent 1 prepared by blending in the insulating resin composition, prepared insulation resin varnish by adding solvent to the low dielectric constant insulating resin composition in the following composition (Low dielectric agent: 32% by volume). The equivalent of the thermosetting agent to the epoxy at this time was 1.0 equivalent.
Low dielectric constant agent 1 50 parts by weight insulating resin composition / cresol novolac type epoxy resin, ESCN-190-3
(Product name, manufactured by Sumitomo Chemical Co., Ltd.) 75 parts by weight, thermosetting agent dicyandiamide (manufactured by Nippon Carbide Co., Ltd.) 4 parts by weight, thermosetting agent novolak phenol resin, HP-850
(Trade name, manufactured by Hitachi Chemical Co., Ltd.) 21 parts by weight imidazole, 2-phenylimidazole (trade name, 2PZ, manufactured by Shikoku Chemical Industries, Ltd.)
0.5 parts by weight Solvent / methyl ethyl ketone 75 parts by weight

(6) Next, this insulating resin varnish was applied onto a copper foil having a thickness of 18 μm and dried at 100 ° C. for 20 minutes to produce an insulating resin film with a copper foil having a thickness of 100 ± 3 μm. A copper foil having a thickness of 18 μm was placed on the resin surface of the produced insulating resin film with copper foil, and an insulating resin film with double-sided copper foil was produced under the press conditions of 170 ° C., 90 minutes, 1.0 MPa.

Example 2
In Example 1, porous silica 1 was changed to porous silica 2 [oil absorption amount 330 ml / 100 g (fillable void ratio: 87.9%), surface average pore diameter 10 nm, specific gravity 2.2, average particle diameter 2.6 μm, SYLYSIA310P (trade name) manufactured by Fuji Silysia Chemical Co., Ltd.], the blending amount is 100 parts by weight, the blending amount of the condensed phosphate ester is 1200 parts by weight, and after cooling, it is put into a four-neck separable flask. A low dielectric constant agent 2 was obtained (filling rate 100%), except that the amount of ethyl methyl ketone was 2600 wt. Low dielectric constant agent 2 had a low dielectric constant component content: 87.9%.
Then, it carried out similarly to Example 1, produced the low dielectric constant insulating resin composition, the insulating resin varnish, the insulating resin film with copper foil, and the insulating resin film with double-sided copper foil, and performed the characteristic test.

Example 3
In Example 1, porous silica 1 was changed to porous silica 3 [oil absorption amount 80 ml / 100 g (fillable porosity: 63.8%), surface average pore diameter 17 mm, specific gravity 2.2, average particle diameter 3.1 μm, L-31-C (trade name) manufactured by Asahi Glass Co., Ltd.], the blending amount is 200 parts by weight, and the blending amount of the condensed phosphate ester is 400 parts by weight. A low dielectric constant agent 3 was obtained in the same manner as in Example 1 except that the amount of ethyl methyl ketone added was 1200 weight and the low dielectric constant agent 3 was produced (filling rate 100%). Low dielectric constant agent 3 had a low dielectric constant component content: 63.8%.
Then, it carried out similarly to Example 1, produced the low dielectric constant insulating resin composition, the insulating resin varnish, the insulating resin film with copper foil, and the insulating resin film with double-sided copper foil, and performed the characteristic test.

Example 4
In Example 1, except that the low dielectric constant agent 1 was 100 parts by weight and the methyl ethyl ketone used for making the insulating resin varnish was 200 parts by weight, the low dielectric constant agent 4 (Filling rate 100%) was obtained. Low dielectric constant agent 4 had a low dielectric constant component content: 76.7%.
Then, it carried out similarly to Example 1, produced the low dielectric constant insulating resin composition, the insulating resin varnish, the insulating resin film with copper foil, and the insulating resin film with double-sided copper foil, and performed the characteristic test.

Comparative Example 1
Nonporous silica and phosphoric acid ester calculated as having the same weight as the low dielectric constant agent of Example 1 are blended in the following composition to produce a low dielectric constant insulating resin composition, and a solvent is blended to insulate. A functional resin varnish was prepared. The equivalent of the thermosetting agent to the epoxy at this time was 1.0 equivalent.
Condensed phosphate ester phosphate ester, PX-200
(Product name, manufactured by Daihachi Chemical Industry Co., Ltd.) 30 parts by weight of nonporous silica, SO-25R, average particle size of 0.5 μm
(Product name, manufactured by Admatechs Co., Ltd.) 20 parts by weight insulating resin composition / cresol novolac epoxy resin, ESCN-190-3
(Product name, manufactured by Sumitomo Chemical Co., Ltd.) 75 parts by weight / thermosetting agent dicyandiamide (product name, manufactured by Nippon Carbide Corporation) 4 parts by weight / thermosetting agent novolak phenol resin, HP-850
(Trade name, manufactured by Hitachi Chemical Co., Ltd.) 21 parts by weight imidazole, 2-phenylimidazole (trade name, 2PZ manufactured by Shikoku Chemicals Co., Ltd.)
0.5 parts by weight solvent, methyl ethyl ketone 75 parts by weight (5) Next, this insulating resin varnish is coated on a copper foil and dried at 100 ° C. for 10 minutes to have an insulating property with a copper foil of 100 ± 3 μm. A resin film was prepared. A copper foil having a thickness of 18 μm was placed on the resin surface of the produced insulating resin film with copper foil, and an insulating resin film with double-sided copper foil was produced under the press conditions of 170 ° C., 90 minutes, 1.0 MPa.

Blank 1
In Comparative Example 1, except for the condensed phosphate ester, the rest was the same as in Comparative Example 1, and the low dielectric constant insulating resin composition, the insulating resin varnish, the insulating resin film with copper foil, and the insulating resin with double-sided copper foil were used. A film was prepared and subjected to a characteristic test.

Characteristic test The following characteristics were evaluated about the produced insulating resin film with a double-sided copper foil.
The results are shown in Table 1.
・ Heat resistance: Using an insulating resin film with double-sided copper foil cut to 50 mm x 50 mm, measure the time until the insulating resin film with double-sided copper foil swells when floated on molten solder at 260 ° C and 288 ° C did.
Copper foil peel strength: measured in accordance with JIS-C-6481.
Moreover, the copper foil on both sides was removed and the following characteristics were evaluated. The results are shown in Table 1.
Glass transition temperature: The glass transition temperature (Tg) was measured using a thermomechanical analyzer (TMA-4000, manufactured by Mac Science Co., Ltd.) at a temperature increase rate of 5 ° C./min. The results are shown in Table 1.
Dielectric constant: The dielectric constant at 1 GHz was measured using an RF impedance / material analyzer (manufactured by Agilent Technologies, HP 4291B).

  Here, blank 1 is phosphoric acid which is a low dielectric constant component in the low dielectric constant insulating resin composition of Comparative Example 1 and a low dielectric constant agent in the low dielectric constant insulating resin composition of Examples 1 to 4. It has almost the same composition as the insulating resin composition excluding the ester. Therefore, it is the (blank) which shows the characteristic of the insulating resin composition before making low dielectric constant.

  As is apparent from Table 2, in Examples 1 to 4 using the low dielectric constant insulating resin composition containing the low dielectric constant agent of the present invention, the dielectric constant was lowered to 3.5 or less. . And since heat resistance is 60 seconds or more, heat resistance was maintained. Since the peel strength was 1.0 kN / m or more, the adhesiveness and mechanical strength were maintained. Since the glass transition temperature was 150 ° C. or higher, the glass transition temperature and the dimensional stability against heat were maintained.

  On the other hand, in Comparative Example 1 using the low dielectric constant insulating resin composition not containing the low dielectric constant agent of the present invention, the comparative example 1 has a peel strength of 1.3 kN / m. The transition temperature and dielectric constant were adversely affected.

Example 5
(1) In Example 1, except that the resin composition was prepared by using 50 parts by weight of the low dielectric constant agent 1, and 100 parts by weight of methyl ethyl ketone used for making the insulating resin varnish was the same as in Example 1. Thus, an insulating resin varnish was obtained.
(2) After impregnating the obtained insulating resin varnish into a glass cloth (# 2116, E-glass) having a thickness of about 0.1 mm, it was dried by heating at 150 ° C. for 3 to 10 minutes to have a resin content of 43% by weight. A prepreg was obtained. Four of these prepregs were stacked, and a copper foil having a thickness of 18 μm was stacked on both sides thereof, and a double-sided copper-clad laminate was produced under press conditions of 170 ° C., 90 minutes, 3.0 MPa.

Example 6
In Example 2, a resin composition was prepared with 50 parts by weight of the low dielectric constant agent 2, and the insulation was performed in the same manner as in Example 2 except that 100 parts by weight of methyl ethyl ketone was used for making the insulating resin varnish. Resin varnish was obtained.
A double-sided copper clad laminate was produced in the same manner as in Example 5 except that the above insulating resin varnish was used instead of the insulating resin varnish of Example 5.

Example 7
In Example 3, the resin composition was prepared with 50 parts by weight of the low dielectric constant agent 3, and the insulation was performed in the same manner as in Example 3 except that 100 parts by weight of methyl ethyl ketone was used for making the insulating resin varnish. Resin varnish was obtained.
A double-sided copper clad laminate was produced in the same manner as in Example 5 except that the above insulating resin varnish was used instead of the insulating resin varnish of Example 5.

Example 8
A double-sided copper-clad laminate was prepared in the same manner as in Example 5 except that the insulating resin varnish of Example 4 was used instead of the insulating resin varnish of Example 5.

Comparative Example 2
A double-sided copper clad laminate was prepared in the same manner as in Example 5 except that the insulating resin varnish of Comparative Example 1 was used instead of the insulating resin varnish of Example 5.

Blank 2
A double-sided copper clad laminate was produced in the same manner as in Example 5 except that the insulating resin varnish of Comparative Example 2 was used instead of the insulating resin varnish of Example 5.

The obtained double-sided copper-clad laminate was evaluated for the following characteristics.
The results are shown in Table 4.
-Heat resistance: Using a double-sided copper-clad laminate cut to 50 mm x 50 mm, the time until the double-sided copper-clad laminate swelled when floated on molten solder at 260 ° C was measured.
Copper foil peel strength: measured in accordance with JIS-C-6481.
Dielectric constant: The dielectric constant at 1 GHz was measured using an RF impedance / material analyzer (manufactured by Agilent Technologies, HP 4291B).

  Here, the blank 2 is a low dielectric constant agent in the low dielectric constant insulating resin compositions of Examples 5 to 8, and the low dielectric constant component phosphate ester in the low dielectric constant insulating resin composition of Comparative Example 2. The composition has almost the same composition as the insulating resin composition except for. Therefore, it is the (blank) which shows the characteristic of the insulating resin composition before making low dielectric constant.

  As is clear from Table 4, in Examples 5 to 8 of the double-sided copper-clad laminate using the low dielectric constant insulating resin composition containing the low dielectric constant material of the present invention, the dielectric constant was 3.9 or less. The dielectric constant was lowered. And since heat resistance is 60 seconds or more, heat resistance was maintained. Since the peel strength was 1.1 kN / m or more, the adhesion and mechanical strength were maintained.

  On the other hand, in Comparative Example 2 of the double-sided copper clad laminate using the insulating resin composition not containing the low dielectric constant agent of the present invention, Comparative Example 2 cannot be press-molded because the heat resistance is not sufficient. A double-sided copper-clad laminate could not be produced.

  In the present invention, only the relative dielectric constant is reduced, and the performance of other characteristics (heat resistance (including glass transition temperature, dimensional stability against heat, etc.), adhesion, and mechanical strength (for example, peel strength)) is maintained. The obtained low dielectric constant insulating resin composition is achieved.

Claims (20)

A low dielectric constant insulating resin composition containing an insulating resin composition and a low dielectric constant material, a low dielectric low dielectric constant material is a multi-porous material, embedded in the porous substance in The dielectric constant of the low dielectric constant component in the low dielectric constant agent is smaller than the dielectric constant of the insulating resin composition, and the low dielectric constant component is plasticizers resins, thermosetting resins state, and are one or more selected from the group consisting of a photosensitive resin and phosphoric acid esters, viscosity or pour point of the low dielectric constant component 10000 poise (1 kPa · s) or less low dielectric constant resin composition, characterized in der Rukoto.   The low dielectric constant component is polyolefin, polypropylene ether, polyamide, polyamideimide, polyarylate, thermoplastic polyimide, polyether ether ketone, polyethylene oxide, polyethylene terephthalate, polyvinylidene chloride, polyvinyl chloride, polycarbonate, polyvinyl acetate, Polystyrene, polybutadiene, polyvinyl ether; epoxy resin, xylene resin, guanamine resin, diallyl phthalate resin, unsaturated polyester resin, phenol resin, unsaturated polyester resin, polyimide, polyurethane, maleic resin, melamine resin, urea resin; epoxy acrylate; 2. The low dielectric constant insulating resin composition according to claim 1, wherein the composition is one or more selected from the group consisting of phosphate esters.   The low dielectric constant insulating resin composition according to claim 1 or 2, wherein an average pore diameter of the surface of the porous material is 1-1000 nm.   The low dielectric constant insulating resin composition according to any one of claims 1 to 3, wherein an average particle diameter of the porous material is 0.05 to 100 µm.   The low dielectric constant component is embedded in the porous material in an amount of 1 to less than 100% by volume with respect to the pore volume of the porous material. Low dielectric constant insulating resin composition.   The low dielectric constant insulating resin composition according to claim 1, wherein the low dielectric constant component is solid at 20 ° C. or higher.   The low dielectric constant insulating resin composition according to any one of claims 1 to 6, wherein the porous volume of the porous material is 10 to 700 ml / 100 g in terms of oil absorption.   The low dielectric constant insulating resin composition according to claim 1, wherein the porous substance is porous silica.   The low dielectric constant insulating resin composition according to any one of claims 1 to 8, wherein the low dielectric constant component is thermosetting.   The low dielectric constant insulating resin composition according to any one of claims 1 to 9, wherein the insulating resin composition is thermosetting.   The low dielectric constant insulating resin composition according to any one of claims 1 to 8, wherein the low dielectric constant component is a phosphate ester or a polyolefin.   The low dielectric constant insulating resin composition according to claim 1, wherein the insulating resin composition contains an epoxy resin. An insulating resin varnish comprising the low dielectric constant insulating resin composition according to any one of claims 1 to 12 and a solvent.   The low dielectric constant insulating resin composition according to any one of claims 1 to 12 is impregnated and applied to one substrate selected from the group consisting of glass cloth, glass nonwoven fabric and organic woven fabric. A prepreg.   The insulating resin film formed by coating the low dielectric constant insulating resin composition of any one of Claims 1-12 on a plastic film or an organic film.   The insulating resin film with copper foil formed by coating the low-dielectric-constant insulating resin composition of any one of Claims 1-12 on copper foil.   A laminate obtained by laminate molding using the prepreg according to claim 14.   A laminate comprising the insulating resin film according to claim 15 or 16.   An insulating layer is formed using the prepreg according to claim 14.   An insulating layer is formed using the insulating resin film according to claim 15 or 16, and a multilayer wiring board.