KR102511759B1 - Curable resin composition, dry film, cured product and electronic component - Google Patents

Abstract

A curable resin composition capable of obtaining a cured product capable of maintaining a low coefficient of thermal expansion not only at room temperature but also in a high-temperature region exceeding 200 ° C. during component mounting, while having low dielectric properties without impairing other properties, using the same Provides dry films, cured products and electronic components. A curable resin composition comprising fine powder having at least one dimension smaller than 100 nm and an active ester compound. They are the dry film, hardened|cured material, and electronic component which used this curable resin composition.

Description

Curable resin composition, dry film, cured product and electronic component

The present invention relates to a curable resin composition, a dry film, a cured product, and an electronic component.

As the electronic component, there are a wiring board, active components and passive components fixed to the wiring board, and the like. Wiring boards include wiring of conductors on an insulating substrate to connect and fix active components, passive components, etc. Depending on the application, multilayer insulation and conductor layers are used, or flexible insulation substrates are used. It is an important electronic component in electronic devices. Further, wiring boards are also used for semiconductor packages, and curable resin compositions for wiring boards and dry films are used as wiring boards or outer layers after mounting semiconductors. Examples of active components and passive components include transistors, diodes, resistors, coils, capacitors, and the like.

In recent years, along with the miniaturization of electronic devices, the required characteristics of electronic components have become stricter. Higher density of wiring has been demanded for wiring boards, and low thermal expansibility is required for materials of wiring boards in order to ensure reliability of wiring and parts connecting parts. Active components and passive components are also required to be miniaturized and highly integrated, and low thermal expansion properties are also required to ensure reliability.

As a method of achieving low thermal expansion, for example, Patent Document 1 proposes a method of obtaining a low coefficient of thermal expansion by filling a resin with an inorganic filler.

Japanese Unexamined Patent Publication No. 2001-72834

However, in the material described in Patent Literature 1, a large amount of inorganic filler must be filled in order to obtain a desired low thermal expansion coefficient, and there is a problem that the physical properties of the cured product are poor.

Further, the inventors of the present invention have found that the material described in Patent Literature 1 has a large coefficient of thermal expansion in the temperature range at the time of component mounting exceeding 200 ° C., and there is a new problem that there is no effect to ensure reliability.

Therefore, an object of the present invention is to provide a curable resin composition capable of obtaining a cured product capable of maintaining a low coefficient of thermal expansion even in a high-temperature region during component mounting.

Another object of the present invention is to provide a dry film, cured product, and electronic component using the curable resin composition.

As a result of intensive studies, the present inventors have found that the above problems can be solved by using an active ester compound together with a fine powder having at least one dimension smaller than 100 nm, and have solved the present invention.

That is, the curable resin composition of the present invention is characterized by containing fine powder having at least one dimension smaller than 100 nm (hereinafter, simply referred to as "fine powder") and an active ester compound. It is preferable that curable resin composition of this invention contains a filler further.

The dry film of the present invention is characterized by having a resin layer formed by applying the curable resin composition on a film and drying it.

The cured product of the present invention is characterized in that the curable resin composition or the resin layer of the dry film is cured.

The electronic component of the present invention is characterized by comprising the above cured product.

Here, the fine powder in the present invention is not particularly limited in shape, and shapes such as fibrous, scaly, granular, etc. can be used, and "at least one dimension smaller than 100 nm" means any one of one-dimensional, two-dimensional and three-dimensional means less than 100 nm. For example, in the case of fibrous fine powder, the second dimension is smaller than 100 nm and has expansion to the remaining one dimension, and in the case of scaly fine powder, one side is smaller than 100 nm and expansion to the remaining two dimensions is exemplified. , and in the case of granular fine powder, those smaller than 100 nm in all three dimensions are exemplified.

In the present invention, the one-dimensional, two-dimensional and three-dimensional size of the fine powder is determined by SEM (Scanning Electron Microscope), TEM (Transmission Electron Microscope) or AFM (Atomic Force Microscope). It can be measured by observing with a microscope (atomic force microscope), etc.

For example, in the case of scaly fine powder, the average value of the smallest one-dimensional thickness is measured, and this average thickness is set to be less than 100 nm. Specifically, by drawing a diagonal line in the micrograph, randomly extracting 12 fine powders whose thickness is measurable and located near them, removing the thickest fine powder and the thinnest fine powder, the remaining 10 points Thickness is measured, and the average value is less than 100 nm.

In the case of fibrous fine powder, the average value of the smallest two-dimensional fiber diameter is measured, and this average fiber diameter is set to be smaller than 100 nm. Specifically, a line is drawn diagonally in the micrograph, 12 points of fine powder in the vicinity are randomly extracted, and after removing the fine powder with the largest fiber diameter and the smallest fiber diameter, the remaining 10 fiber diameters are It is measured and the average value is less than 100 nm.

In the case of granular fine powder, the average value of particle diameter is measured, and this average particle diameter is made smaller than 100 nm. Specifically, a line is drawn diagonally in the micrograph, 12 points of fine powder in the vicinity are randomly extracted, and after removing the fine powder with the largest and smallest particle sizes, the remaining 10 particle sizes are measured, It is assumed that the average value is less than 100 nm.

In the case of a fine powder having expansion to another dimension such as fibrous or scale-like, the expansion is, for example, less than 1000 nm, preferably less than 650 nm, and more preferably less than 450 nm. If the spread is less than 1000 nm, the reinforcing effect due to the interaction between the fine powders can be effectively obtained.

ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide a curable resin composition capable of obtaining a cured product capable of maintaining a low coefficient of thermal expansion even in a high-temperature region during component mounting.

Further, according to the present invention, a dry film, a cured product, and an electronic component using the curable resin composition can be provided.

1 is a partial cross-sectional view showing an example of a configuration of a multilayer printed wiring board according to an example of an electronic component of the present invention.
Fig. 2 is an explanatory diagram showing a test substrate used in Examples.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail.

The curable resin composition of the present invention is characterized by containing fine powder and an active ester compound.

With this configuration, it is possible to maintain a low coefficient of thermal expansion even in the temperature range at the time of component mounting exceeding 200°C, reduce the dielectric constant and dielectric loss tangent, and obtain electronic components having low dielectric properties.

[fine powder]

The fine powder used in the present invention is powder with at least one dimension smaller than 100 nm, and as described above, it is not only close to a fine spherical shape, but also has a fibrous shape with a cross-sectional diameter smaller than 100 nm, and a sheet shape with a thickness smaller than 100 nm (scale above) are also included. Compared to those having three dimensions of 100 nm or more in all three dimensions, such a fine powder has a much larger surface area per unit mass and an increased ratio of atoms exposed to the surface. Therefore, it is considered that the fine powder takes an interaction in which it is attracted to each other, a reinforcing effect is expressed, and the thermal expansion property is lowered. This effect is remarkably expressed in hydrophilic particles among fine powders.

The fine powder may be particles smaller than 100 nm in at least one dimension, and the material is not particularly limited. Examples of the fine powder include carbon-based substances such as fullerene, single-walled carbon nanotubes and multi-layered carbon nanotubes, and inorganic substances such as silver, gold, iron, nickel, titanium oxide, cerium oxide, zinc oxide, silica, and aluminum hydroxide. cellulose nanocrystals obtained by isolating only the crystalline portion from fine cellulose fibers and cellulose raw materials obtained by processing organic substances into nanotubes, nanowires, and nanosheets, minerals such as clay, smectite, and bentonite, and plant fibers. Fine chitin obtained by opening chitin obtained from particles, crustaceans, etc., fine chitosan subjected to further alkali treatment, and the like are exemplified, and two or more of these may be used in combination. Examples of the hydrophilic fine powder include metal oxide fine particles such as titanium oxide, metal hydroxide fine particles such as aluminum hydroxide, mineral fine particles such as clay, fine cellulose fibers, and fine chitin. Among these fine powders, fine cellulose fibers are particularly preferred from the viewpoints of reinforcing effect and ease of handling. Cellulose nanocrystal particles are also preferred.

As the fine powder as described above, when a hydrophilic fine powder is used, it is preferable to hydrophobize the particles or to perform surface treatment using a coupling agent or the like. For this treatment, known and usual methods suitable for fine powder can be used.

The blending amount of the fine powder in the present invention is preferably 0.04 to 64% by mass, more preferably 0.08 to 30% by mass, still more preferably 0.1 to 10% by mass with respect to the total amount of the composition excluding the solvent. . When the blending amount of the fine powder is 0.04% by mass or more, the effect of reducing the coefficient of linear expansion can be obtained satisfactorily. On the other hand, when it is 64% by mass or less, film forming properties are improved.

(fine cellulose fibers)

Among the fine powder according to the present invention, fine cellulose fibers can be obtained as follows, but are not limited to these.

As the raw material of fine cellulose fibers, pulp obtained from natural plant fiber raw materials such as wood, hemp, bamboo, cotton, jute, kenaf, beets, agricultural residues, cloth, and regenerated cellulose fibers such as rayon and cellophane can be used. , among others, pulp is particularly suitable. As the pulp, chemical pulps such as kraft pulp and sulfite pulp obtained by pulping plant raw materials chemically, mechanically, or using both together, semichemical pulps, chemical ground pulps, chemical mechanical pulps, thermomechanical pulps, chemical thermomechanical pulps , refiner mechanical pulp, ground wood pulp, and deinking waste pulp mainly composed of these plant fibers, magazine waste pulp, corrugated cardboard waste pulp, and the like can be used. Among them, various types of kraft pulp derived from softwoods having high fiber strength, such as softwood unbleached kraft pulp, softwood oxygen-exposed unbleached kraft pulp, and softwood bleached kraft pulp are particularly suitable.

The above raw materials are mainly composed of cellulose, hemicellulose and lignin, and the content of lignin is usually about 0 to 40% by mass, particularly about 0 to 10% by mass. Regarding these raw materials, the amount of lignin can be adjusted by performing lignin removal or bleaching treatment as needed. In addition, the measurement of lignin content can be performed by the Klason method.

In the cell walls of plants, cellulose molecules are not single molecules but are regularly aggregated to form microfibrils (fine cellulose fibers) having crystallinity gathered in dozens, which serve as the basic skeletal material of plants. Therefore, in order to manufacture fine cellulose fibers from the raw materials, the raw materials are subjected to beating or grinding treatment, high-temperature and high-pressure steam treatment, treatment with phosphate, etc., treatment of oxidizing cellulose fibers using an N-oxyl compound as an oxidation catalyst, etc. By doing this, a method of unraveling the fiber to nano size can be used.

The beating or crushing treatment is a method of obtaining fine cellulose fibers by directly applying force to the raw material such as the pulp, mechanically beating or crushing, and releasing the fibers. More specifically, for example, pulp or the like is mechanically treated with a high-pressure homogenizer or the like, and cellulose fibers having a fiber diameter of about 0.1 to 10 μm are unwound to obtain an aqueous suspension of about 0.1 to 3% by mass, and this is further ground with a grinder or the like. By repeating the grinding or melting treatment with, fine cellulose fibers having a fiber diameter of about 10 to 100 nm can be obtained.

The above grinding or melting treatment can be performed using, for example, a grinder "Pure Fine Mill" manufactured by Kurita Kikai Seisakusho or the like. This grinder is a millstone type grinder that pulverizes raw materials into ultra-fine particles by the impact, centrifugal force, and shear force generated when raw materials pass through the gap between the upper and lower two grinders. It is possible to be angry at the same time. In addition, the said grinding|pulverization or fusion|melting process can also be performed using Masyuki Sangyo Co., Ltd. product ultra-fine grinding machine "Super mass colloidal". The Super Mass Colloider is a grinding machine that enables ultra-fine granulation to the extent that it feels like melting beyond the realm of simple grinding. The Super Mass Colloider is a millstone-type ultra-fine grinder composed of two upper and lower non-porous grindstones whose spacing can be freely adjusted. The upper grindstone is fixed and the lower grindstone rotates at high speed. The raw material put into the hopper is sent to the gap between the upper and lower grindstones by centrifugal force, and the raw material is gradually ground and ultra-fine by the strong compression, shear, and rolling friction force generated there.

In addition, the high-temperature and high-pressure steam treatment is a method of obtaining fine cellulose fibers by exposing raw materials such as the pulp to high-temperature and high-pressure steam to unravel the fibers.

In addition, the treatment with a phosphate or the like is a treatment method in which the surface of the raw material such as the pulp is phosphate esterified to weaken the binding force between the cellulose fibers, and then a refiner treatment is performed to unravel the fibers to obtain fine cellulose fibers. For example, raw materials such as the pulp are immersed in a solution containing 50% by mass of urea and 32% by mass of phosphoric acid, the solution is sufficiently impregnated between cellulose fibers at 60 ° C., and then heated at 180 ° C. to phosphorylate After advancing and washing with water, hydrolysis treatment was performed at 60 ° C. for 2 hours in a 3% by mass aqueous hydrochloric acid solution, followed by further washing with water, and then in a 3% by mass aqueous sodium carbonate solution at room temperature for 20 minutes. Phosphorylation is completed by a degree treatment, and fine cellulose fibers can be obtained by fibrillating the treated product with a refiner.

Further, the treatment of oxidizing cellulose fibers using the N-oxyl compound as an oxidation catalyst is a method of obtaining fine cellulose fibers by oxidizing raw materials such as the pulp and then refining them.

First, an aqueous dispersion is prepared by dispersing natural cellulose fibers in about 10 to 1000 times the amount (by mass) of water on an absolute dry basis using a mixer or the like. Examples of natural cellulose fibers used as a raw material of the fine cellulose fibers include wood pulp such as coniferous pulp and hardwood pulp, non-wood pulp such as barley pulp and bagasse pulp, cotton pulp such as cotton lint and cotton linter, Bacterial cellulose etc. are mentioned. These may be used individually by 1 type, or may be used combining 2 or more types suitably. In addition, these natural cellulose fibers may be subjected to treatment such as beating in order to increase the surface area in advance.

Next, in the aqueous dispersion, natural cellulose fibers are oxidized using an N-oxyl compound as an oxidation catalyst. Examples of such N-oxyl compounds include TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl), 4-carboxy-TEMPO, 4-acetamide-TEMPO, and 4-amino-TEMPO. , 4-dimethylamino-TEMPO, 4-phosphonooxy-TEMPO, 4-hydroxyTEMPO, 4-oxyTEMPO, 4-methoxyTEMPO, 4-(2-bromoacetamide)-TEMPO, 2-azaa TEMPO derivatives having various functional groups at the C4 position, such as dathanane N-oxyl, etc. can be used. As the added amount of these N-oxyl compounds, a catalytic amount is sufficient, and can usually be in the range of 0.1 to 10% by mass on an absolute dry basis with respect to natural cellulose fibers.

In the oxidation treatment of the natural cellulose fibers, an oxidizing agent and a co-oxidizing agent are used in combination. Examples of the oxidizing agent include subhalogenic acid, hypohalogenic acid and perhalogenic acid and their salts, hydrogen peroxide and perorganic acids, among which alkali metal hypohalides such as sodium hypochlorite and sodium hypobromite are suitable. . Moreover, as a co-oxidizing agent, an alkali metal bromide, such as sodium bromide, can be used, for example. The amount of the oxidizing agent is usually in the range of about 1 to 100% by mass on an absolute dry basis with respect to the natural cellulose fiber, and the amount of the co-oxidizing agent is usually in the range of about 1 to 30% by mass on an absolute dry basis with respect to the natural cellulose fiber. range to be

In the oxidation treatment of the natural cellulose fibers, it is preferable to maintain the pH of the aqueous dispersion in the range of 9 to 12 from the viewpoint of efficiently advancing the oxidation reaction. In addition, the temperature of the aqueous dispersion during the oxidation treatment can be arbitrarily set in the range of 1 to 50 ° C., and the reaction is possible even at room temperature without temperature control. As reaction time, it can be set as the range of 1 to 240 minutes. Further, a penetrating agent may be added to the aqueous dispersion in order to penetrate the drug to the inside of the natural cellulose fibers and introduce more carboxyl groups into the fiber surface. Examples of the penetrant include anionic surfactants such as carboxylate salts, sulfate ester salts, sulfonate salts, and phosphate ester salts, and nonionic surfactants such as polyethylene glycol type and polyhydric alcohol type.

After the oxidation treatment of the natural cellulose fibers, it is preferable to perform a purification treatment to remove impurities such as unreacted oxidizing agents and various by-products contained in the aqueous dispersion before micronization. Specifically, for example, a method of repeatedly washing and filtering the natural cellulose fibers treated with water can be used. The natural cellulose fibers obtained after the refining treatment are usually impregnated with an appropriate amount of water and used for the micronization treatment, but may be dried in a fibrous or powdery form if necessary.

Next, the natural cellulose treatment for miniaturization is performed in a state in which the purified natural cellulose fibers, if desired, are dispersed in a solvent such as water. The solvent as the dispersion medium used in the miniaturization treatment is usually preferably water, but if desired, alcohols (methanol, ethanol, isopropanol, isobutanol, sec-butanol, tert-butanol, methyl cellosolve, ethyl cello Solve, ethylene glycol, glycerin, etc.), ethers (ethylene glycol dimethyl ether, 1,4-dioxane, tetrahydrofuran, etc.), ketones (acetone, methyl ethyl ketone, N,N-dimethylformamide, N,N- A water-soluble organic solvent such as dimethylacetamide or dimethylsulfoxide) may be used, or a mixture thereof may be used. The solid content concentration of the natural cellulose fibers in the dispersion of these solvents is preferably 50% by mass or less. When the solid content concentration of the natural cellulose fibers exceeds 50% by mass, it is not preferable because very high energy is required for dispersion. The micronization of natural cellulose treatment is performed using a low pressure homogenizer, a high pressure homogenizer, a grinder, a cutter mill, a ball mill, a jet mill, a beating machine, a disintegrator, a single screw extruder, a twin screw extruder, an ultrasonic stirrer, and a domestic juicer mixer. This can be done using a device.

The fine cellulose fibers obtained by the miniaturization treatment can be in the form of a suspension having an adjusted solid content concentration or in the form of a dried powder, as desired. Here, in the case of a suspension, only water may be used as a dispersion medium, or a mixed solvent of water and other organic solvents such as alcohols such as ethanol, surfactants, acids, and bases may be used.

Cellulose molecules in which the hydroxyl group at the C6 position of the constituent unit of the cellulose molecule is selectively oxidized to a carboxyl group via an aldehyde group by the oxidation treatment and micronization treatment of the natural cellulose fiber, and the content of such a carboxyl group is 0.1 to 3 mmol/g. It is possible to obtain highly crystalline fine cellulose fibers having the predetermined number average fiber diameter. This highly crystalline fine cellulose fiber has a cellulose type I crystal structure. This means that these fine cellulose fibers are micronized by surface oxidation of naturally occurring cellulose molecules having an I-type crystal structure. That is, in natural cellulose fibers, fine fibers called microfibrils produced in the course of their biosynthesis are bundled to form a high-order solid structure, and a strong cohesive force between the microfibrils (hydrogen between surfaces) binding) is weakened by introduction of an aldehyde group or a carboxyl group by oxidation treatment, and further subjected to micronization treatment to obtain fine cellulose fibers. By adjusting the conditions of oxidation treatment, the polarity is changed by increasing or decreasing the content of carboxyl groups, and the average fiber diameter, average fiber length, average aspect ratio, etc. of fine cellulose fibers can be controlled by electrostatic repulsion or refinement treatment of carboxyl groups. can

The reason why the natural cellulose fiber has an I-type crystal structure is that in the diffraction profile obtained by measuring its wide-angle X-ray diffraction image, typical peaks are located at two positions around 2θ = 14 to 17 ° and around 2θ = 22 to 23 °. You can identify from what you have. In addition, the introduction of carboxyl groups into the cellulose molecules of the fine cellulose fibers can be confirmed by the presence of absorption (near 1608 cm ^-1 ) due to carbonyl groups in the total reflection infrared spectroscopy spectrum (ATR) in the sample from which moisture is completely removed. there is. In the case of a carboxyl group (COOH), absorption exists at 1730 cm ^-1 in the above measurement.

In addition, since halogen atoms are attached or bonded to the natural cellulose fibers after oxidation treatment, dehalogenation treatment may be performed for the purpose of removing these residual halogen atoms. The dehalogenation treatment can be performed by immersing the natural cellulose fibers after oxidation treatment in a hydrogen peroxide solution or an ozone solution.

Specifically, for example, natural cellulose fibers after oxidation treatment are mixed with a hydrogen peroxide solution having a concentration of 0.1 to 100 g/L at a bath ratio of about 1:5 to 1:100, preferably about 1:10 to 1:60 (mass ratio) It is immersed under the condition of The concentration of the hydrogen peroxide solution in this case is preferably 1 to 50 g/L, more preferably 5 to 20 g/L. In addition, the pH of the hydrogen peroxide solution is preferably 8 to 11, more preferably 9.5 to 10.7.

In addition, the amount of carboxyl groups in cellulose relative to the mass of fine cellulose fibers contained in the aqueous dispersion [mmol/g] can be evaluated by the following method. That is, 60 ml of a 0.5 to 1% by mass aqueous dispersion of a fine cellulose fiber sample whose dry mass was precisely determined in advance was prepared, the pH was adjusted to about 2.5 with a 0.1 M hydrochloric acid aqueous solution, and then a 0.05 M sodium hydroxide aqueous solution was added to a pH of about It is added dropwise until it becomes 11, and the electrical conductivity is measured. From the sodium hydroxide amount (V) consumed in the neutralization step of the weak acid in which the change in electrical conductivity is slow, the functional group amount can be determined using the following formula. The amount of this functional group represents the amount of carboxyl groups.

Functional group weight [mmol/g] = V [ml] × 0.05/fine cellulose fiber sample [g]

Further, the fine cellulose fibers used in the present invention may be chemically modified and/or physically modified to enhance functionality. Here, as the chemical modification, a functional group is added by acetalization, acetylation, cyanoethylation, etherification, isocyanate, etc., or an inorganic substance such as silicate or titanate is compounded by a chemical reaction or a sol-gel method, or coating You can do it or do it in any way. As a method of chemical modification, for example, a method of immersing and heating fine cellulose fibers molded into a sheet shape in acetic anhydride is exemplified. Further, fine cellulose fibers obtained by oxidizing cellulose fibers using an N-oxyl compound as an oxidation catalyst may be modified by an ionic bond or an amide bond with an amine compound or a quaternary ammonium compound at the carboxyl group in the molecule. there is.

As a method of physical modification, for example, a metal or ceramic raw material is subjected to a physical vapor deposition method (PVD method) such as vacuum deposition, ion plating, sputtering, or the like, a chemical vapor deposition method (CVD method), or a plating method such as electroless plating or electrolytic plating. A covering method is mentioned. These modifications may be performed before or after the above process.

The number average fiber diameter of the fine cellulose fibers used in the present invention is 3 nm or more and is preferably smaller than 100 nm. Since the minimum diameter of short fine cellulose fibers is 3 nm, if it is less than 3 nm, it cannot be produced substantially, and if it exceeds 100 nm, it is necessary to add excessively in order to obtain the desired effect of the present invention, resulting in deterioration of film forming properties. . In addition, the number average fiber diameter of the fine cellulose fibers can be measured according to the method for measuring the size of the fine powder described above.

(cellulose nanocrystal particles)

In the present invention, the cellulose nanocrystal particles are any particles obtained by hydrolyzing the cellulose raw material with a high concentration of inorganic acid (hydrochloric acid, sulfuric acid, hydrobromic acid, etc.) to isolate only the crystalline portion except for the amorphous portion. Cellulose nanocrystal particles, specifically, can be obtained by hydrolyzing the cellulose raw material with a strong acid of 7 wt% or more, preferably a strong acid of 9 wt% or more, more preferably a strong acid that is easy to high concentration, such as sulfuric acid, at a concentration of 60 wt% or more. It is a crystal that does not contain an amorphous part. By using cellulose nanocrystal particles as fine powder, it is possible to obtain a cured product having various characteristics such as toughness and heat resistance while maintaining a low coefficient of thermal expansion even in the temperature range at the time of component mounting exceeding 200 ° C. An excellent curable resin composition can be provided.

The size of the cellulose nanocrystal particles is preferably 3 to 70 nm in average crystal width and 100 to 500 nm in average crystal length, more preferably 3 to 50 nm in average crystal width, 100 to 400 nm in average crystal length, and more Preferably, the average crystal width is 3 to 10 nm, and the average crystal length is 100 to 300 nm. Here, the crystal width refers to the length of the short side of the particle, and the crystal length refers to the length of the long side of the particle. These cellulose nanocrystal particles have a much larger surface area per unit mass than those having a width or length greater than these, increasing the ratio of atoms exposed to the surface. Therefore, it is considered that the reinforcing effect is expressed by taking an interaction in which the cellulose nanocrystal particles are attracted to each other, and the thermal expansibility is lowered.

Here, the size (average crystal width, average crystal length) of the cellulose nanocrystal particles, SEM (Scanning Electron Microscope; Scanning Electron Microscope), TEM (Transmission Electron Microscope; Transmission Electron Microscope) or AFM (Atomic Force Microscope; atomic force microscope) It can be measured by observing with a force microscope), etc.

Specifically, a diagonal line is drawn in the photomicrograph, 12 particles of which size can be measured are randomly extracted and the size of the remaining 10 points is determined after removing the largest and smallest particles. , crystal length), and the averaged values are the average crystal width and average crystal length of the cellulose nanocrystal particles.

As the cellulose nanocrystal particles, you may use together 2 or more types of thing with different raw material cellulose.

Such cellulose nanocrystal particles are preferably subjected to hydrophobic treatment, surface treatment using a coupling agent, and the like. For this treatment, known and usual methods suitable for cellulose nanocrystal particles can be used.

Here, the cellulose raw material includes paper pulp, cotton-based pulp such as cotton linter and cotton lint, non-wood-based pulp such as hemp, barley barley, and bagasse, cellulose isolated from squirts and seaweed, etc., but is not particularly limited. . Among these, pulp for papermaking is preferable in terms of ease of acquisition, and cotton and sea squirt are preferable in terms of being able to produce CNC with more excellent heat resistance.

As the pulp for papermaking, hardwood kraft pulp, softwood kraft pulp, and the like are exemplified.

Examples of hardwood kraft pulp include bleached kraft pulp (LBKP), unbleached kraft pulp (LUKP), and oxygen bleached kraft pulp (LOKP).

Examples of softwood kraft pulp include bleached kraft pulp (NBKP), unbleached kraft pulp (NUKP), and oxygen bleached kraft pulp (NOKP).

In addition, chemical pulp, semi-chemical pulp, mechanical pulp, non-wood pulp, and deinking pulp using waste paper as a raw material may be used. Examples of chemical pulp include sulfite pulp (SP) and soda pulp (AP). Examples of the semi-chemical pulp include semi-chemical pulp (SCP) and chemical ground wood pulp (CGP). Examples of mechanical pulp include ground wood pulp (GP) and thermomechanical pulp (TMP, BCTMP). Non-wood pulp includes paper mulberry, Samji paper mulberry, hemp, kenaf, and the like as raw materials.

These cellulose raw materials may be used individually by 1 type, or may be used in mixture of 2 or more types. In addition, cellulose nanofibers (hereinafter, simply referred to as "CNF") produced by a mechanical fibrillation method, a phosphoric acid esterification method, a TEMPO oxidation method, or the like may be used as a cellulose raw material.

Subsequently, the hydrolysis of the cellulose raw material as described above is carried out by, for example, treating an aqueous suspension or slurry containing the cellulose raw material with sulfuric acid, hydrochloric acid, hydrobromic acid or the like, or treating the cellulose raw material as it is in an aqueous solution of sulfuric acid, hydrochloric acid, hydrobromic acid or the like. It can be done by suspending. In particular, when pulp is used as a cellulose raw material, it is preferable to hydrolyze the pulp after forming it into flocculent fibers using a cutter mill, pin mill, or the like, from the viewpoint of being able to perform a uniform hydrolysis treatment.

In this hydrolysis treatment, temperature conditions are not particularly limited, but can be, for example, 25 to 90°C. Also, the conditions for the time of the hydrolysis treatment are not particularly limited, but can be, for example, 10 to 120 minutes.

In addition, about the cellulose nanocrystal particle obtained by hydrolysis-processing the cellulose raw material in this way, neutralization treatment can be performed using alkali, such as sodium hydroxide, for example.

Cellulose nanocrystal particles obtained in this way can be atomized if necessary. In this atomization process, a processing device and a processing method are not particularly limited.

As an atomization processing device, for example, a grinder (millstone type grinder), a high pressure homogenizer, an ultra high pressure homogenizer, a high pressure impact type grinder, a ball mill, a bead mill, a disk type refiner, a conical refiner, a twin shaft kneader, a vibration A mill, a homomixer under high-speed rotation, an ultrasonic disperser, a beater, or the like can be used.

In the case of the atomization treatment, it is preferable to dilute the cellulose nanocrystal particles with water and an organic solvent alone or in combination to form a slurry, but it is not particularly limited. Examples of preferred organic solvents include alcohols, ketones, ethers, dimethylsulfoxide (DMSO), dimethylformamide (DMF), and dimethylacetamide (DMAc). 1 type of dispersion medium may be sufficient as it, and 2 or more types may be sufficient as it. In addition, solid content other than cellulose nanocrystal particles, for example, elements having hydrogen bonds, may be included in the dispersion medium.

In addition, the cellulose nanocrystal particles used in the present invention may be chemically modified and/or physically modified to enhance functionality. Here, as the chemical modification, a functional group is added by acetalization, acetylation, cyanoethylation, etherification, isocyanate, etc., or an inorganic substance such as silicate or titanate is compounded by a chemical reaction or a sol-gel method, or coating You can do it or do it in any way. As physical modification, it can be performed by plating or vapor deposition.

[Active ester compound]

An active ester compound may be used individually by 1 type, or may use 2 or more types together. The active ester compound is not particularly limited, but one having two or more active ester groups in one molecule is preferable. An active ester compound can generally be obtained by a condensation reaction of at least one of a carboxylic acid compound and a thiocarboxylic acid compound and at least one of a hydroxy compound and a thiol compound. Examples of the active ester compound include dicyclopentadienyl diphenol ester compound, bisphenol A diacetate, diphenyl phthalate, diphenyl terephthalate, and bis[4-(methoxycarbonyl)phenyl] terephthalate.

The blending amount of the active ester compound is preferably 0.5% by mass or more and 80% by mass or less, more preferably 1% by mass or more and 40% by mass or less, still more preferably 1.5% by mass or more, based on the total amount of the composition excluding the solvent. It is 30 mass % or less. When the compounding quantity of the said active ester compound is 0.5 mass % or more, a low coefficient of thermal expansion can be ensured satisfactorily. On the other hand, when it is 80 mass % or less, sclerosis|hardenability improves.

In the present invention, curable resins such as thermosetting resins other than active ester compounds can be used in combination as desired.

(thermosetting resin)

The thermosetting resin may be a resin that is cured by heating and exhibits electrical insulation properties, and examples thereof include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol E type epoxy resins, bisphenol M type epoxy resins, Bisphenol type epoxy resins such as bisphenol P type epoxy resin and bisphenol Z type epoxy resin, novolac type epoxy resins such as bisphenol A novolak type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, and biphenyl type epoxy Resins, biphenylaralkyl type epoxy resins, arylalkylene type epoxy resins, tetraphenylolethane type epoxy resins, phenoxy type epoxy resins, dicyclopentadiene type epoxy resins, norbornene type epoxy resins, adamantane type epoxy resins, flue Orene-type epoxy resin, glycidyl methacrylate copolymerized epoxy resin, cyclohexylmaleimide and glycidyl methacrylate copolymerized epoxy resin, epoxy-modified polybutadiene rubber derivative, CTBN-modified epoxy resin, trimethylolpropane polyglyc Cidyl ether, phenyl-1,3-diglycidyl ether, biphenyl-4,4'-diglycidyl ether, 1,6-hexanediol diglycidyl ether, diglycol of ethylene glycol or propylene glycol Cidyl ether, sorbitol polyglycidyl ether, tris (2,3-epoxypropyl) isocyanurate, triglycidyl tris (2-hydroxyethyl) isocyanurate, phenol novolak resin, cresol novolak resin Phenoxy, novolac-type phenolic resins such as bisphenol A novolak resins, unmodified resolphenol resins, resol-type phenolic resins such as oil-modified resolphenol resins modified with tung oil, linseed oil, walnut oil, etc. Resins, triazine ring-containing resins such as urea (urea) resins and melamine resins, unsaturated polyester resins, bismaleimide resins, diallylphthalate resins, silicone resins, resins having benzoxazine rings, norbornene resins, cyanate resins , isocyanate resin, urethane resin, benzocyclobutene resin, maleimide resin, bismaleimide triazine resin, polyazomethine resin, thermosetting polyimide, and the like.

Moreover, when using the resin composition of this invention as an alkali development type photo-soldering resist which can be developed with aqueous alkali solution, it is also preferable to use carboxyl group-containing resin.

(Carboxyl group-containing resin)

As the carboxyl group-containing resin, both photosensitive carboxyl group-containing resins having one or more photosensitive unsaturated double bonds and carboxyl group-containing resins having no photosensitive unsaturated double bonds can be used, and are not limited to specific ones. As the carboxyl group-containing resin, resins enumerated below can be particularly suitably used.

(1) A carboxyl group-containing resin obtained by copolymerization of an unsaturated carboxylic acid and a compound having an unsaturated double bond, and a carboxyl group-containing resin obtained by modifying it to adjust molecular weight and acid value.

(2) Photosensitive carboxyl group-containing resin obtained by reacting a compound having an oxirane ring and an ethylenically unsaturated group in one molecule with a carboxyl group-containing (meth)acrylic copolymer resin.

(3) A copolymer of a compound having one epoxy group and an unsaturated double bond in one molecule and a compound having an unsaturated double bond is reacted with an unsaturated monocarboxylic acid, and the secondary hydroxyl group produced by this reaction is saturated or A photosensitive carboxyl group-containing resin obtained by reacting an unsaturated polybasic acid anhydride.

(4) A photosensitive hydroxyl group and carboxyl group obtained by reacting a hydroxyl group-containing polymer with a saturated or unsaturated polybasic acid anhydride and then reacting a compound having one epoxy group and an unsaturated double bond in each molecule with the carboxylic acid produced by the reaction. oleoresin.

(5) A photosensitive carboxyl group-containing resin obtained by reacting a polyfunctional epoxy compound with an unsaturated monocarboxylic acid and reacting a polybasic acid anhydride with part or all of the secondary hydroxyl groups produced by this reaction.

(6) A polyfunctional epoxy compound and a compound having two or more hydroxyl groups and one reactive group other than the hydroxyl group reacting with the epoxy group in a molecule are reacted with a monocarboxylic acid containing an unsaturated group, and a polybasic acid anhydride is added to the obtained reaction product. Carboxyl group-containing photosensitive resin obtained by making it react.

(7) A photosensitive resin containing a carboxyl group obtained by reacting a monocarboxylic acid containing an unsaturated group with a reaction product of a resin having a phenolic hydroxyl group and an alkylene oxide or cyclic carbonate and reacting a polybasic acid anhydride with the obtained reaction product.

(8) A polyfunctional epoxy compound, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, and a monocarboxylic acid containing an unsaturated group are reacted, with respect to the alcoholic hydroxyl group of the obtained reaction product, polybasic acid anhydride Photosensitive resin containing a carboxyl group obtained by reacting an anhydride group.

[filler]

It is preferable to further contain fillers other than the fine powder in the resin composition of the present invention. Examples of the filler include barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, silicon nitride, and aluminum nitride. Among these fillers, silica, especially spherical silica, is preferable from the viewpoints of having a small specific gravity, being able to be blended in a composition at a high proportion, and having excellent low thermal expansion properties. It is preferable that it is 3 micrometers or less, and, as for the average particle diameter of a filler, 1 micrometer or less is more preferable. In addition, the average particle diameter of a filler can be calculated|required by a laser diffraction type particle size distribution analyzer.

The blending amount of the filler is 1 to 90% by mass, preferably 2 to 80% by mass, and more preferably 5 to 75% by mass, based on the total amount of the composition excluding the solvent. By carrying out the compounding quantity of a filler in the said range, the coating film performance of the hardened|cured material after hardening can be ensured favorably.

The resin composition of the present invention can further suitably incorporate other common ingredients according to its use. As other commonly used compounding components, a curing catalyst, a colorant, an organic solvent, etc. are mentioned, for example.

As a curing catalyst, it is a phenolic compound; Imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2- imidazole derivatives such as phenylimidazole and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; Amines such as dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine Hydrazine compounds, such as adipic acid dihydrazide and sebacic acid dihydrazide; Phosphorus compounds, such as a triphenylphosphine, etc. are mentioned. In addition, as commercially available products, for example, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (made by Shikoku Kasei Kogyo Co., Ltd.), U-CAT3503N, U-CAT3502T, DBU, DBN, U-CATSA102, U- CAT5002 (San Afro Co., Ltd. product) etc. are mentioned, You may use individually or in mixture of 2 or more types. Similarly, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S -Triazine, 2-vinyl-4,6-diamino-S-triazine/isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine/isocyanuric acid adduct S-triazine derivatives such as nuric acid adducts can also be used.

In the present invention, phenolic compounds are particularly preferably used. Examples of the phenolic compound include phenol novolak resins, alkylphenol novolac resins, triazine structure-containing novolac resins, bisphenol A novolac resins, dicyclopentadiene type phenol resins, xylock type phenol resins, copna resins, and terpenes. Phenolic compounds such as modified phenol resins and polyvinylphenols, naphthalene-based curing agents, and fluorene-based curing agents may be used alone or in combination of two or more. Examples of the phenolic compounds include HE-610C, 620C manufactured by Air Water Co., Ltd., TD-2131, TD-2106, TD-2093, TD-2091, TD-2090, VH-4150, and VH manufactured by DIC Corporation. -4170, KH-6021, KA-1160, KA-1163, KA-1165, TD-2093-60M, TD-2090-60M, LF-6161, LF-4871, LA-7052, LA-7054, LA-7751 , LA-1356, LA-3018-50P, EXB-9854, SN-170, SN180, SN190, SN475, SN485, SN495, SN375, SN395 manufactured by Nippon Steel Sumikin Chemical Co., Ltd., JX Nikko Nisseki Energy ( DPP manufactured by Meiwa Kasei Co., Ltd., HF-1M, HF-3M, HF-4M, H-4, DL-92, MEH-7500, MEH-7600-4H, MEH-7800, MEH- 7851, MEH-7851-4H, MEH-8000H, MEH-8005, Mitsui Chemicals Co., Ltd. XL, XLC, RN, RS, RX and the like, but are not limited thereto. These phenolic compounds can be used individually or in combination of 2 or more types.

The compounding amount of the curing catalyst used in the present invention is sufficient in a proportion normally used, and for example, in the case of a phenolic compound, 1 to 150 parts by mass, preferably 5 to 100 parts by mass, relative to 100 parts by mass of the thermosetting resin, More preferably, it is 10 to 50 parts by mass, and in the case of other curing catalysts, it is 0.01 to 10 parts by mass, preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass.

As the coloring agent, commonly known coloring agents such as red, blue, green, and yellow can be used, and any of pigments, dyes, and pigments may be used. However, from the viewpoint of reducing the environmental load and affecting the human body, it is preferable not to contain halogen.

Blue colorant:

As the blue colorant, there are phthalocyanine-based and anthraquinone-based, and the pigment-based compound is classified as a pigment, specifically, the following color index (C.I.; The Society of Dyers and Colorists (The Society of Dyers and Colourists) numbered: Pigment Blue 15, Pigment Blue 15:1, Pigment Blue 15:2, Pigment Blue 15:3, Pigment Blue 15:4, Pigment Blue 15:4 ment blue 15:6, pigment blue 16, pigment blue 60.

As dye system, solvent blue 35, solvent blue 63, solvent blue 68, solvent blue 70, solvent blue 83, solvent blue 87, solvent blue 94, solvent blue 97, solvent blue 122, solvent blue 136, solvent blue 67, solvent blue 70, etc. can be used. In addition to the above, metal-substituted or unsubstituted phthalocyanine compounds can also be used.

Green colorant:

As the green colorant, there are similarly phthalocyanine-based and anthraquinone-based, and specifically, Pigment Green 7, Pigment Green 36, Solvent Green 3, Solvent Green 5, Solvent Green 20, Solvent Green 28 and the like can be used. In addition to the above, metal-substituted or unsubstituted phthalocyanine compounds can also be used.

Yellow colorant:

Examples of the yellow colorant include monoazo, disazo, condensed azo, benzimidazolone, isoindolinone, and anthraquinone, and specifically include the following.

Anthraquinone: Solvent Yellow 163, Pigment Yellow 24, Pigment Yellow 108, Pigment Yellow 193, Pigment Yellow 147, Pigment Yellow 199, Pigment Yellow 202.

Isoindolinone type: Pigment Yellow 110, Pigment Yellow 109, Pigment Yellow 139, Pigment Yellow 179, Pigment Yellow 185.

Condensed Azo: Pigment Yellow 93, Pigment Yellow 94, Pigment Yellow 95, Pigment Yellow 128, Pigment Yellow 155, Pigment Yellow 166, Pigment Yellow 180.

Benzimidazolone series: Pigment Yellow 120, Pigment Yellow 151, Pigment Yellow 154, Pigment Yellow 156, Pigment Yellow 175, Pigment Yellow 181.

Monoazo: Pigment Yellow 1, 2, 3, 4, 5, 6, 9, 10, 12, 61, 62, 62:1, 65, 73, 74, 75, 97, 100, 104, 105, 111 , 116, 167, 168, 169, 182, 183.

Disazo: Pigment Yellow 12, 13, 14, 16, 17, 55, 63, 81, 83, 87, 126, 127, 152, 170, 172, 174, 176, 188, 198.

Red colorant:

Examples of the red colorant include monoazo, disazo, azolake, benzimidazolone, perylene, diketopyrrolopyrrole, condensed azo, anthraquinone, and quinacridone. Specifically, the following can hear

Monoazo: Pigment Red 1, 2, 3, 4, 5, 6, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23, 31, 32, 112, 114, 146, 147 , 151, 170, 184, 187, 188, 193, 210, 245, 253, 258, 266, 267, 268, 269.

Disazo: Pigment Red 37, 38, 41.

Monoazolake system: Pigment Red 48:1, 48:2, 48:3, 48:4, 49:1, 49:2, 50:1, 52:1, 52:2, 53:1, 53: 2, 57:1, 58:4, 63:1, 63:2, 64:1, 68.

Benzimidazolone series: Pigment Red 171, Pigment Red 175, Pigment Red 176, Pigment Red 185, Pigment Red 208.

Perylene series: Solvent Red 135, Solvent Red 179, Pigment Red 123, Pigment Red 149, Pigment Red 166, Pigment Red 178, Pigment Red 179, Pigment Red 190, Pigment Red 194, Pigment Red 224 .

Diketopyrrolopyrrole type: Pigment Red 254, Pigment Red 255, Pigment Red 264, Pigment Red 270, Pigment Red 272.

Condensed Azo: Pigment Red 220, Pigment Red 144, Pigment Red 166, Pigment Red 214, Pigment Red 220, Pigment Red 221, Pigment Red 242.

Anthraquinone: Pigment Red 168, Pigment Red 177, Pigment Red 216, Solvent Red 149, Solvent Red 150, Solvent Red 52, Solvent Red 207.

Quinacridone: Pigment Red 122, Pigment Red 202, Pigment Red 206, Pigment Red 207, Pigment Red 209.

In addition, you may add coloring agents, such as purple, orange, brown, and black, for the purpose of adjusting color tone.

Specifically, Pigment Violet 19, 23, 29, 32, 36, 38, 42, Solvent Violet 13, 36, C.I. Pigment Orange 1, C.I. Pigment Orange 5, C.I. Pigment Orange 13, C.I. Pigment Orange 14, C.I. Pigment Orange 16, C.I. Pigment Orange 17, C.I. Pigment Orange 24, C.I. Pigment Orange 34, C.I. Pigment Orange 36, C.I. Pigment Orange 38, C.I. Pigment Orange 40, C.I. Pigment Orange 43, C.I. Pigment Orange 46, C.I. Pigment Orange 49, C.I. Pigment Orange 51, C.I. Pigment Orange 61, C.I. Pigment Orange 63, C.I. Pigment Orange 64, C.I. Pigment Orange 71, C.I. Pigment Orange 73, C.I. Pigment There are C.I. Pigment Brown 23, C.I. Pigment Brown 25, C.I. Pigment Black 1, and C.I. Pigment Black 7.

The specific blending ratio of the colorant can be appropriately adjusted depending on the type of colorant to be used or the type of other additives.

As an organic solvent, Ketones, such as methyl ethyl ketone and cyclohexanone; Aromatic hydrocarbons, such as toluene, xylene, and tetramethylbenzene; Methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monoethyl ether, etc. glycol ethers of; esters such as ethyl acetate, butyl acetate, cellosolve acetate, diethylene glycol monoethyl ether acetate, and esterified products of the above glycol ethers; alcohols such as ethanol, propanol, ethylene glycol, and propylene glycol; aliphatic hydrocarbons such as octane and decane; and petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

Moreover, known and usual additives, such as an antifoamer/leveling agent, a thixotropy imparting agent/thickener, a coupling agent, a dispersing agent, and a flame retardant, can be contained as needed.

Curable resin composition of this invention may be used after being made into a dry film, or may be used as a liquid. In addition, the curable resin composition of the present invention can also be used as a prepreg obtained by coating or impregnating sheet-shaped fibrous substrates such as glass cloth, nonwoven fabrics of glass and aramid, and semi-curing. When using as a liquid phase, it may be 1-component or 2-component or more. As a two-component composition, it is good also as a composition which divided fine cellulose fiber and an active ester compound, for example.

The dry film of this invention has a resin layer obtained by apply|coating and drying curable resin composition of this invention on a carrier film. When forming a dry film, first, the curable resin composition of the present invention is diluted with the organic solvent and adjusted to an appropriate viscosity, followed by a comma coater, a blade coater, a lip coater, a rod coater, a squeeze coater, a reverse coater, a transfer roll coater, It is applied to a uniform thickness on a carrier film by a gravure coater, spray coater or the like. Thereafter, a resin layer can be formed by drying the applied composition at a temperature of 40 to 130° C. for 1 to 30 minutes. The coating film thickness is not particularly limited, but is generally appropriately selected from the range of 3 to 150 µm, preferably 5 to 60 µm, as the film thickness after drying.

As the carrier film, a plastic film is used, and for example, a polyester film such as polyethylene terephthalate (PET), a polyimide film, a polyamideimide film, a polypropylene film, a polystyrene film, or the like can be used. The thickness of the carrier film is not particularly limited, but is generally appropriately selected from the range of 10 to 150 μm. More preferably, it is the range of 15-130 micrometers.

After forming a resin layer containing the curable resin composition of the present invention on a carrier film, a peelable cover film is further laminated on the surface of the resin layer for the purpose of preventing dirt from adhering to the surface of the resin layer. It is desirable to do As a peelable cover film, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, surface-treated paper, etc. can be used, for example. As a cover film, when peeling a cover film, the adhesive force between a resin layer should just be smaller than the adhesive force of a resin layer and a carrier film.

Moreover, in this invention, a resin layer may be formed by apply|coating and drying the curable resin composition of this invention on the said cover film, and a carrier film may be laminated|stacked on the surface. That is, when manufacturing a dry film in this invention, you may use any of a carrier film and a cover film as a film to which curable resin composition of this invention is apply|coated.

The cured product of the present invention is obtained by curing the resin layer in the curable resin composition of the present invention or the dry film of the present invention.

The electronic component of the present invention includes the cured product of the present invention, and specifically includes a printed wiring board. The cured product of the present invention can be suitably used in electronic parts requiring interlayer insulation reliability. In particular, by using the resin composition of the present invention as an interlayer insulating material, a multilayer printed wiring board can have good interlayer insulation reliability.

Fig. 1 shows a partial cross-sectional view showing an example of a configuration of a multilayer printed wiring board according to an example of an electronic component of the present invention. The illustrated multilayer printed wiring board can be manufactured as follows, for example. First, a through hole is formed in the core substrate 2 on which the conductor pattern 1 is formed. Formation of a through hole can be performed by appropriate means, such as a drill, a mold punch, and a laser beam. Then, a roughening process is performed using a roughening agent. In general, the roughening treatment is performed by swelling with an organic solvent such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, methoxypropanol or an alkaline aqueous solution such as caustic soda or caustic potassium, dichromate, This is done using an oxidizing agent such as permanganate, ozone, hydrogen peroxide/sulfuric acid, or nitric acid.

Next, the conductor pattern 3 is formed by a combination of electroless plating or electrolytic plating. The step of forming a conductor layer by electroless plating is a step of immersing in an aqueous solution containing a catalyst for plating, adsorbing the catalyst, and then immersing in a plating solution to deposit plating. According to a conventional method (subtractive method, semi-additive method, etc.), a predetermined circuit pattern is formed on the conductor layer on the surface of the core substrate 2, and as shown, conductor patterns 3 are formed on both sides. form At this time, a plating layer is also formed in the through hole, and as a result, the connection part 4 of the conductor pattern 3 of the multilayer printed wiring board and the connection part 1a of the conductor pattern 1 are electrically connected, and through A hole 5 is formed.

Then, after applying a thermosetting composition, for example, a thermosetting composition is applied by a suitable method such as screen printing, spray coating, or curtain coating, and then cured by heating to form the interlayer insulating layer 6 . In the case of using a dry film or prepreg, the interlayer insulating layer 6 is formed by heating and curing by lamination or hot plate pressing. Subsequently, vias 7 for electrically connecting the connection parts of each conductor layer are formed by appropriate means, such as laser light, and the conductor pattern 8 is formed in the same manner as the conductor pattern 3 do. In addition, the interlayer insulating layer 9, the via 10, and the conductor pattern 11 are formed in the same manner. After that, a multilayer printed wiring board is manufactured by forming the solder resist layer 12 on the outermost layer. In the above, an example in which an interlayer insulating layer and a conductor layer are formed on a laminated substrate has been described, but a single-sided board or a double-sided board may be used instead of the laminated board.

Example

Hereinafter, the present invention will be described in more detail using examples.

[Manufacture of fine cellulose fibers]

Preparation Example 1 (CNF1)

Bleached kraft pulp fibers of coniferous trees (Machenzie CSF 650 ml manufactured by Fletcher Challenge Canada) were sufficiently stirred with 9900 g of ion-exchanged water, and then TEMPO (2,2,6,6-tetramethylpiperi manufactured by ALDRICH) was mixed with respect to 100 g of the pulp mass. 1.25 mass % of din 1-oxyl free radical), 12.5 mass % of sodium bromide, and 28.4 mass % of sodium hypochlorite were added in this order. Using a pH stat, 0.5 M sodium hydroxide was added dropwise to maintain the pH at 10.5. After the reaction was carried out for 120 minutes (20°C), dropping of sodium hydroxide was stopped to obtain oxidized pulp. The obtained oxidized pulp was sufficiently washed with ion-exchanged water, and then subjected to dehydration treatment. Thereafter, 3.9 g of oxidized pulp and 296.1 g of ion-exchanged water were subjected to micronization treatment twice at 245 MPa using a high-pressure homogenizer (Starburst Labo HJP-2 5005, manufactured by Sugino Machine Co., Ltd.), and a carboxyl group-containing fine cellulose fiber dispersion (Solid content concentration: 1.3% by mass) was obtained.

Subsequently, 4088.75 g of the obtained carboxyl group-containing fine cellulose fiber dispersion was placed in a beaker, and 4085 g of ion-exchanged water was added to obtain a 0.5% by mass aqueous solution, followed by stirring for 30 minutes at room temperature (25°C) with a mechanical stirrer. Subsequently, 245 g of 1 M hydrochloric acid aqueous solution was injected, and it was made to react under room temperature for 1 hour. After completion of the reaction, the mixture was reprecipitated with acetone, filtered, and then washed with acetone/ion-exchanged water to remove hydrochloric acid and salts. Finally, acetone was added and filtered to obtain an acetone-containing acid type cellulose fiber dispersion (solid content concentration: 5.0% by mass) in a state in which carboxyl group-containing fine cellulose fibers were swollen in acetone. After completion of the reaction, the mixture was filtered, and then washed with ion-exchanged water to remove hydrochloric acid and salts. After solvent substitution with acetone, solvent substitution with DMF was performed to obtain a DMF-containing acid type cellulose fiber dispersion (average fiber diameter: 3.3 nm, solid content concentration: 5.0% by mass) in a state in which carboxyl group-containing fine cellulose fibers were swollen.

Preparation Example 2 (CNF2)

40 g of the DMF-containing acid type cellulose fiber dispersion obtained in Production Example 1 and 0.3 g of hexylamine were placed in a beaker equipped with a magnetic stirrer and a stirrer, and dissolved in 300 g of ethanol. The reaction solution was reacted at room temperature (25°C) for 6 hours. After completion of the reaction, the mixture was filtered, washed with DMF and solvent-substituted to obtain a fine cellulose fiber composite (solid content concentration: 5.0% by mass) in which amines were linked to fine cellulose fibers through ionic bonds.

CNF produced by the method of Preparation Example 2 has particularly good dispersibility, and can be dispersed in a general method without using a special dispersing machine such as a high-pressure homogenizer.

Preparation Example 3 (CNF3)

10% by mass of fine cellulose fibers (BiNFi-s manufactured by Sugino Machine Co., Ltd., average fiber diameter: 80 nm) was dehydrated and filtered, 10 times the amount of carbitol acetate was added to the mass of the filtrate, stirred for 30 minutes, and then filtered. This substitution operation was repeated three times, and carbitol acetate in an amount 20 times the mass of the filtrate was added to prepare a fine cellulose fiber dispersion (solid content concentration: 5.0% by mass).

[Preparation of Cellulose Nanocrystal Particles]

Production Example 4 (CNC1)

A first sheet of dried softwood bleached kraft pulp was treated with a cutter mill and a pin mill to obtain cotton fibers. 100 g of this cotton fiber was taken by absolute dry mass, suspended in 2 L of 64% sulfuric acid aqueous solution, and hydrolyzed at 45 DEG C for 45 minutes.

After filtering the suspension thus obtained, 10 L of ion-exchanged water was injected and stirred to uniformly disperse the mixture to obtain a dispersion. Next, the process of filtering and dewatering the dispersion liquid was repeated three times to obtain a dewatering sheet. Next, the obtained dewatering sheet was diluted with 10 L of ion-exchanged water, and 1N sodium hydroxide aqueous solution was added little by little while stirring to adjust the pH to about 12. After that, the suspension was filtered and dehydrated, 10 L of ion-exchanged water was added, and the steps of stirring and dehydrating by filtration were repeated twice.

Next, ion-exchanged water was added to the obtained dewatering sheet to prepare a 2% suspension. This suspension was passed 10 times at a pressure of 245 MPa with a wet atomization device (“Altimizer” manufactured by Sugino Machine) to obtain an aqueous dispersion of cellulose nanocrystal particles.

Then, after performing solvent substitution with acetone, solvent substitution was performed with DMF to obtain a DMF dispersion liquid (solid content concentration: 5.0% by mass) in a state in which cellulose nanocrystal particles were swollen. As a result of observing and measuring the cellulose nanocrystal particles in the obtained dispersion by AFM, the average crystal width was 10 nm and the average crystal length was 200 nm.

Production Example 5 (CNC2)

Except for changing the cellulose raw material of Production Example 4 to absorbent cotton (manufactured by Hakujuji Co., Ltd.), it was prepared in the same way to obtain a DMF dispersion (solid content concentration: 5.0 mass%) in a state in which cellulose nanocrystal particles were swollen. As a result of observing and measuring the cellulose nanocrystal particles in the obtained dispersion by AFM, the average crystal width was 7 nm and the average crystal length was 150 nm.

According to the description in Tables 1 to 4, each component was mixed and stirred, and then dispersed 6 times using a high-pressure homogenizer, Nanovater NVL-ES008 manufactured by Yoshida Kikai Kogyo, to prepare each composition. In addition, the numerical value in Tables 1-4 shows a mass part.

[Measurement of coefficient of thermal expansion]

Each composition was applied to a PET film having a thickness of 38 μm with an applicator having a gap of 120 μm and dried in a hot air circulation drying furnace at 90° C. for 10 minutes to obtain a dry film having a resin layer of each composition. Thereafter, the resin layer of each composition was laminated on a copper foil having a thickness of 18 μm by pressure with a vacuum laminator at 60° C. and a pressure of 0.5 MPa for 60 seconds, and the PET film was peeled off. Then, it was hardened by heating at 180°C for 30 minutes in a hot air circulation type drying furnace, and the copper foil was peeled off to obtain a sample of the cured film. The prepared sample for measuring thermal expansion was cut into a 3 mm width x 30 mm length. This test piece was heated at 5°C/min to 20 to 250°C in a tensile mode with a chuck interval of 16 mm, a load of 30 mN, and a nitrogen atmosphere using TMA (Thermomechanical Analysis) Q400 manufactured by T.A Instruments, and then heated to 250 to 20°C. The temperature was decreased at 5°C/min until the temperature was measured. At the time of temperature fall, the coefficient of thermal expansion (ppm/K) at 25°C and 200°C was determined. In addition, the temperature of the rapid change point of the thermal expansion coefficient was made into Tg (glass transition point). Results are shown in Tables 1 to 4.

[Relative permittivity, dielectric loss tangent]

Each composition was applied to a PET film having a thickness of 38 μm with an applicator having a gap of 200 μm and dried at 90° C. for 20 minutes in a hot air circulation type drying furnace to obtain a dry film having a resin layer of each composition. Thereafter, an electrolytic copper foil having a thickness of 18 μm was pressed with the glossy side upward to a substrate fixed with tape to a FR-4 copper-clad laminate having a thickness of 1.6 mm with a vacuum laminator at 60 ° C. and a pressure of 0.5 MPa for 60 seconds. Each composition The resin layer was laminated, the PET film was peeled off, and cured by heating at 180°C for 30 minutes in a hot air circulation type drying furnace. And the fixed tape was peeled off, the electrolytic copper foil was peeled, and it cut out in the size of 1.7 mm x 100 mm, and it was set as the evaluation sample. The measurement was performed with a network analyzer E-507 manufactured by Keysight Technologies using a cavity resonator (5 GHz) manufactured by Kanto Denshi Oyo Kaihatsu Co., Ltd. In evaluation of the dielectric constant, those having an average value measured three times and less than 2.8 were rated as ◎, those having an average of 2.8 or more and less than 3.0 as ○, and those having an average value of 3.0 or more as ×. In the evaluation of the dielectric loss tangent, those with an average value of less than 0.02 measured three times were rated as ○, and those with an average value of 0.02 or more were evaluated as ×. Each result is shown in Tables 1-4.

[Solder heat resistance]

On an FR-4 copper-clad laminate with a size of 150 mm × 95 mm and a thickness of 1.6 mm, each composition was screen-printed with an 80 mesh Tetron bias plate to form a full-surface solid pattern, dried in a hot air circulation drying furnace at 80 ° C. for 30 minutes, and then dried at 180 It cured by heating for 30 minutes at °C to obtain a test piece. A rosin-based flux was applied to the cured product side of the composition of this test piece, flowed to a solder layer at 260°C for 60 seconds, washed with propylene glycol monomethyl ether acetate, and then washed with ethanol. With respect to the test pieces, swelling and peeling of the coating film and changes in the surface state were observed visually. An abnormality due to swelling, peeling, dissolution or softening of the surface, etc. was evaluated in the coating film as ×, and an invisible one as Ο. The evaluation results are shown in Tables 1 to 4.

[Insulation]

Each composition was applied to a PET film having a thickness of 38 μm with an applicator having a gap of 120 μm and dried in a hot air circulation drying furnace at 90° C. for 10 minutes to obtain a dry film having a resin layer of each composition. Then, on the A coupon of IPC MULTI-PURPOSE TEST BOARD B-25 formed on a 1.6 mm thick FR-4 substrate with a copper thickness of 35 μm, each composition was compressed for 60 seconds under conditions of 60 ° C. and 0.5 MPa pressure with a vacuum laminator. The resin layer was laminated, the PET film was peeled off, and cured by heating at 180°C for 30 minutes in a hot air circulation type drying furnace. Subsequently, the lower end of the IPC MULTI-PURPOSE TEST BOARD B-25 was cut to make an electrically independent terminal (cut at the dotted line in FIG. 2). Then, a bias of 500 V DC was applied so that the upper portion of the A coupon became the negative electrode and the lower portion became the positive electrode, and the insulation resistance value was measured. In the evaluation, the insulation resistance value of 100 GΩ or more was Ο, and the insulation resistance value of less than 100 GΩ was set as ×. Results are shown in Tables 1 to 4.

*1) Thermosetting resin 1: Epiclone HP-7200 Cyclohexanone varnish having a solid content of 50% by mass (cyclic ether compound having a dicyclopentadiene skeleton)

*2) Thermosetting resin 2: Epiclon N-740 DIC Co., Ltd. cyclohexanone varnish with a solid content of 50% by mass

*3) Thermosetting resin 3: Epiclon 830 manufactured by DIC Co., Ltd.

*4) Thermosetting resin 4: JER827 manufactured by Mitsubishi Chemical Co., Ltd.

*5) Thermosetting resin 5: Bisphenol A diacetate Tokyo Kasei Kogyo Co., Ltd. (active ester)

*6) Thermosetting resin 6: Epiclon HPC-8000-65T manufactured by DIC Co., Ltd. (active ester, solid content: 65% by mass)

*7) Thermosetting resin 7: HF-1 Meiwa Kasei Co., Ltd. 60 mass % solid content cyclohexanone varnish

*8) Curing catalyst 1: 2E4MZ (2-ethyl-4-methylimidazole) manufactured by Shikoku Kasei Kogyo Co., Ltd.

*9) Filler 1: Admapine SO-C2 (Silica) manufactured by Admartex Co., Ltd. Average particle diameter 0.4 to 0.6㎛

*10) Organic solvent 1: dimethylformamide

*11) Defoamer 1: BYK-352 Big Chemie Japan Co., Ltd.

*12) Filler 2: B-30 Sakai Kagaku Kogyo Co., Ltd. barium sulfate

*13) Filler 3: DAW-07 Alumina manufactured by Denka Co., Ltd.

*14) Dispersant 1: DISPERBYK-111 manufactured by Big Chemie

As is clear from the results shown in Tables 1 to 4, by including fine powder such as fine cellulose fibers or cellulose nanocrystal particles and an active ester compound, a low coefficient of thermal expansion can be maintained not only at room temperature but also in a high temperature region during component mounting. It was also confirmed that a curable resin composition having low dielectric properties can be obtained. In addition, from the evaluation results of solder heat resistance, it was confirmed that each composition of the Examples was excellent in heat resistance and chemical resistance and could be used as a composition for a wiring board.

1, 3, 8, 11 conductor patterns
2 core board
1a, 4 connection part
5 through hole
6, 9 interlayer insulating layer
7, 10 vias
12 solder resist layer

Claims (5)

A fine powder having at least one dimension smaller than 100 nm and an active ester compound,
The fine powder is curable resin composition, characterized in that it comprises at least one of fine cellulose fibers or cellulose nanocrystal particles. The curable resin composition according to claim 1, further comprising a filler. A dry film characterized by having a resin layer obtained by applying and drying the curable resin composition according to claim 1 on a film. A cured product characterized in that the resin layer of the curable resin composition according to claim 1 or the dry film according to claim 3 is cured. An electronic component comprising the cured product according to claim 4.

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