JP3367178B2 - Organic binder for ceramic molding, method for producing the same, and ceramic substrate using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for molding a so-called ceramic such as alumina from the viewpoints of low pollution, resource saving and safety, that is, for manufacturing a molded body and a green sheet made of a ceramic precursor. The present invention relates to such organic binders, and particularly to organic binders for ceramics that are water-based and have excellent debinding properties.

[0002]

[Prior art]

(B) Conventionally, organic binders such as polyvinyl butyral resins and polyacrylic acid ester resins have been generally used as binders for ceramics. This binder is dissolved or dispersed in an organic solvent such as alcohol, ketone, chlorine-based solvent or aromatic solvent, mixed with ceramic fine powder, kneaded and dispersed for a long time in a ball mill or the like to form a slip state. Eggplant After defoaming, a sheet having a certain thickness is cast on a substrate such as a polyester film by a doctor blade method or the like, and dried by heating to form a green sheet.

(B) As a water-soluble binder for ceramics, a water-soluble polyvinyl acetal having an acetalization degree of 10 mol% or less is disclosed in JP-A-56-76405.
JP-A-64-29408 discloses a cold water-soluble polyvinyl acetal having an acetalization degree of 10 to 30 mol%, and a modified polyvinyl alcohol having a hydrophobic group or a specific ionic hydrophilic group in its side chain as an aqueous organic binder.
It is known from Japanese Patent Publication No. 156959.

(C) As water-soluble poly (meth) acrylic acid ester-based binders, JP-B-1-53233, JP-B-1-44668 and JP-A-1-286955 are known. In these, a copolymer of (meth) acrylic acid ester and (meth) acrylic acid is neutralized (pH adjusted) with ammonia, trialkylamine such as trimethylamine, dimethylaminoalcohol, amines such as monoethanolamine. .

Further, (meth) acrylic acid is used as an emulsion-based binder obtained by emulsion-polymerizing a vinyl monomer using a surfactant, and neutralized with ammonia (pH
Adjustments), JP-A-60-180955, JP-A-60-180956, JP-A-61-151060, JP-A-1-286955.
JP-A-63-260855 which has a crosslinked structure
The publication is known.

(E) (a) α-olefin polymer, (b) (meth) acrylic acid ester alone or (meth) acrylic acid ester monomer and styrenic monomer,
(C) JP-A-3-131604 using a system in which a swelled product consisting of a polymerization initiator is dispersed in an aqueous medium containing a dispersant for polymerization (for example, a water-soluble polymer polyvinyl alcohol) and suspension polymerization is performed as a binder. The gazette is known.

(F) In JP-A-59-128266, (a) 100 parts by weight of a water-soluble polymer component,
(B) A composite binder for ceramic molding containing a hydrophobic polymer component in an amount of 1 to 1000 parts by weight is known.

On the other hand, (G) Japanese Patent Laid-Open No. 59-995.
JP-A-60-254697 discloses a method for producing a multilayer ceramic circuit board substrate, and discloses a polymethacrylic acid ester resin as a binder containing a thermal depolymerization type resin therein.

[0009]

[Problems to be Solved by the Invention] However, (a)
In the binder, butyl alcohol, isopropyl alcohol, trichloroethylene, toluene, etc. are used as the organic solvent. However, explosiveness due to ignition, fire risk, odor during molding and drying, especially halogen solvents, have environmental pollution due to evaporative gas, pollution problems such as harmfulness to human body, etc. However, there are many problems such as the need to install waste gas treatment equipment and solvent recovery equipment. In the cases of (b) and (c), since they are water-soluble, they have large hygroscopicity, and there are drawbacks such as variations in the characteristics of the ceramic green sheet. In the case of (d), the ceramic green sheet using the emulsion having a carboxyl group has weaknesses such as low tensile strength and poor gloss and smoothness. Further, since all the binders are inferior in debinding property, there is a problem that the strength of the ceramic sheet and the ceramic substrate after firing is inferior. Also,
In the case of (e), the compatibility between the component (a) and the component (b) is poor, and the mechanical properties of the ceramic precursor composition are poor.
Further, since a polymer having a poor thermal decomposability such as an α-olefin polymer or polyvinyl alcohol is used, there is a problem that the binder removal property is poor and the strength of the ceramic, ceramic sheet and ceramic substrate after firing is poor.
In the case of (f), the method is to add a hydrophobic polymer latex obtained by emulsion polymerization as an aqueous dispersion to a water-soluble polymer solution dissolved in water. Since there are many molecules, it is important that the addition amount is as small as possible in order to use the water-soluble polymer as a binder. Further, when a large amount of water-soluble polymer is present, the green sheet is likely to absorb moisture, so that the mechanical properties and the like greatly vary.
Further, since the hydrophobic polymer latex obtained by emulsion polymerization contains a surfactant, the workability is not good, such as agglomeration depending on the type of ceramic powder and a large amount of bubbles generated during defoaming.

On the other hand, in order to use the polymethacrylic acid ester resin used in (G) as an organic binder for ceramic molding, for example, a ketone solvent such as methyl ethyl ketone or a vapor such as an alcohol solvent such as butyl alcohol is used. Since it uses an organic solvent with high pressure, it lacks fire safety.

[0011]

Therefore, as a result of intensive investigations by the present inventors, an organic binder for ceramic molding obtained by suspension polymerization using a water-soluble polymer as a dispersion stabilizer for polymerization is a binder-free binder. The present invention was completed by discovering that it has excellent properties and is useful as a water-based ceramic organic binder. That is, the present invention is a component (A), which is at least one or more (meth) acrylic acid ester (provided that the alkyl group has 1 to 18 carbon atoms, the cyclic alkyl group has 1 to 12 carbon atoms, or Aryl group ester); 100 wt., Component (B), water-soluble polymer;
1 to 9.5 parts by weight [per 100 parts by weight of component (A)]
In water or a mixed solution of water and a water-soluble organic solvent,
The above object is achieved as an organic binder for ceramic molding, which is characterized in that the component (A) is subjected to suspension (co) polymerization in the presence of a polymerization initiator.

The ceramic powder which is the component (C) is not particularly limited, but it is desirable that the average particle size of the ceramic powder when it is made into a green sheet is 50.0 microns or less. 100 parts by weight of the ceramic powder as the component (C), 30 parts by weight of the organic binder 5 for the ceramic molding as the component (D), and optionally a dispersant and a plasticizer as the component (E). A predetermined molded body is obtained from the ceramic precursor composition slurry containing the above.

The green sheet is a component (C), a ceramic powder 100 having an average particle size of 50.0 microns or less.
30 parts by weight from the above-mentioned ceramic forming organic binder 5, which is the component (D), and (E) if necessary.
The above-mentioned object is achieved by coating the surface of a substrate with a ceramic precursor composition slurry comprising a component, a dispersant and a plasticizer, in a thin film form.

The component (C) has an average particle size of 10.
100 parts by weight of ceramic fine powder having a size of 0 micron or less, 30 parts by weight of the above-mentioned organic binder for ceramics forming 5 which is the component (D), and optionally a dispersant and a plasticizer which are the component (E). Which is composed of a ceramic precursor composition, on which a conductor layer is formed in a pattern, is laminated and adhered to form several layers to several tens layers, and is sintered (a binder removal step, followed by removal of residual carbon). A multilayer ceramic substrate can be obtained by the step (reducing). Alternatively, the green sheet layer is the component (C) and has an average particle size of 1
100 parts by weight of ceramic fine powder having a size of 0.0 micron or less, 30 parts by weight of the above-mentioned organic binder for ceramics forming 5 which is the component (D), and optionally the component (E), a dispersant, a plasticizer. The above object can be achieved by a method for producing a multilayer wiring ceramic substrate which is made of a ceramic precursor composition containing an agent and is formed by sintering a laminate of a plurality of conductor layers via the green sheet layer.

The present invention will be described in detail below.

That is, in the present invention, at least one or more kinds of (meth) acrylic acid ester which is the component (A) (provided that the alkyl group has 1 to 18 carbon atoms and the carbon number is 1 to 1).
Ester of two cyclic alkyl or aryl groups); 1
00 parts by weight, a water-soluble polymer that is the component (B); in water or a mixed solution of water and a water-soluble organic solvent in which 1 to 9.5 parts by weight is dissolved per 100 parts by weight of the component (A), The present invention relates to an organic binder for ceramic molding, which comprises suspending (co) polymerizing the component (A) in the presence of a polymerization initiator, and a method for producing the same.

The component (A) used in the present invention is the main component of the organic binder for ceramic molding and serves to bond the ceramic powder to each other. For example, methyl (meth) acrylate or ethyl (meth) acrylate. , N-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-amyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl ( (Meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, iso Runiru (meth) acrylate, phenyl (meth) acrylate, benzyl (meth)
Acrylate etc. are mentioned. Among these components, from the viewpoint of thermal decomposability, methacrylic acid ester type, and further, n-butyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, n-octyl methacrylate, and methyl methacrylate are preferable.

The component (B) used in the present invention is a water-soluble polymer which is used as a dispersion stabilizer for polymerization when the above component (A) is polymerized in the presence of a polymerization initiator. For example, polyethylene oxide, polyvinyl-2-pyrrolidone, polyvinyl-2-pyrrolidone copolymer, poly (2
-Oxazoline) type and the like are used. From the viewpoint of thermal decomposability, polyethylene oxide is preferable. When used as an organic binder for ceramics, the average particle size (center of particle size distribution) of the polymer is 5 μm or less, preferably 3.0 μm or less. In order to produce such a polymer particle size, it is preferable that the dispersion stabilizer for polymerization, polyethylene oxide, has a viscosity average molecular weight of 10 to 1,000,000. It is preferably 250,000 to 500,000. The amount of the component (B) used is 1 to 9.
5 parts by weight. If the amount used is less than 1 part by weight, no dispersion occurs, or the polymer particles become large and the particles settle. If it exceeds 9.5 parts by weight, the binder will be inferior in debinding property when this water-soluble polymer is used, so that the strength of the sintered body will be low and the dielectric constant will be high, so that it cannot be put to practical use. Since the component (B) is a polymer, the appearance of the produced green sheet is much smoother than when a low-molecular-weight surfactant is used, the ceramic powder does not easily drop from the surface, and foaming does not occur during defoaming. It has little workability. When a water-soluble polymer is used, the humidity causes variations in the mechanical properties of the green sheet and eventually reduces the accuracy of punching. However, since a water-soluble polymer having crystallinity, such as polyethylene oxide (melting point: 60 ° C. to 67 ° C., viscosity average molecular weight: 100 to 1,000,000), has a low hygroscopic property, it is considered to be a polymer of the component (A). It was found that even if mixed and used as a binder, it is not so sensitive to humidity. It was also found that the performance of the water-based organic binder obtained by the present invention is equal to or higher than that of a green sheet prepared from an organic solvent-based binder composed of the same components.

Further, if necessary, in combination with at least one kind, hydroxyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate are added to the component (A). Three
It can also be used in the range of 0% by weight or less. If it exceeds 30% by weight, a stable suspension cannot be obtained due to aggregation of polymer particles dispersed in the suspension during suspension polymerization, and cannot be put to practical use.
Similarly, in combination of at least one or more if necessary, ethylene, isobutylene, ethylene-based monomers such as methacrylonitrile, styrene, styrene-based monomers such as α-methylstyrene, maleic acid diester, fumaric acid diester, Unsaturated diester monomers such as itaconic acid diester and citraconic acid diester can be used in an amount of 50% by weight or less. When it exceeds 50% by weight, when this copolymer is used as a binder and a ceramic sintered body is used,
Since the debinding property is poor, the strength of the sintered body is low, and the dielectric constant is high, so that it cannot be put to practical use. The purpose of copolymerizing the vinyl monomer such as ethylene with the component (A) is to improve thermal decomposability and improve mechanical properties.

Further, the plasticizer used together with the binder is basically difficult to azeotrope with water or an aqueous solvent,
In addition, it has good compatibility with polymers obtained from vinyl monomers. For example, dibutyl phthalate (abbreviated as DBP), di-2-ethylhexyl phthalate (DOP),
Diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), diheptyl phthalate (DH
P), di-n-octyl phthalate (N-DOP) butyl benzyl phthalate (BBP), phthalate esters such as ethyl phthalyl ethyl glycolate, di 2-ethylhexyl adipate (DOA), dibutyl diglycol adipate (BXA), etc. Of aliphatic ester, tripropylene glycol methyl ether (TPM), dipropylene glycol-n-butyl ether (DPnB),
Tripropylene glycol-n-butyl ether (TP
nB), propylene glycol phenyl ether (PP
Examples include propylene glycol ethers such as h). Preferably, DOP, DINP, DIDP, DH
P and N-DOP are good. The plasticizer may be added according to each form and is not particularly limited. That is, it suffices that the mechanical properties of the ceramic precursor composition formed by using the organic binder for ceramics are maintained and the handling property is excellent. That is, the mechanical properties of the green sheet obtained by changing the addition amount of the plasticizer can be adjusted by the plasticizer. As one guideline, the elongation is required to be about 5 to 25% in order to obtain the handleability of the green sheet and the drilling accuracy. The plasticizer may be added during or after suspension polymerization of the vinyl monomer. It is preferably added at the time of polymerization in order to prevent adhesion between polymer particles.

The solid content of the organic binder for ceramic molding used in the present invention is 50% by weight or less, 15% by weight or less.
That is all. If it exceeds 50% by weight, the particle size of the component (A) becomes large, and if it is less than 15% by weight, workability is deteriorated.

The method for producing the organic binder for ceramic molding used in the present invention is as follows. In water or a mixed liquid of water and a water-soluble organic solvent, the component (B) and the monomer as the component (A) are added in a total amount of 100 parts by weight. 1 to 9.5 parts by weight are dissolved. In this solution, component (A) is added in the presence of a polymerization catalyst with heating and vigorous stirring to carry out a polymerization or copolymerization reaction.

Examples of the solvent used in the present invention include water, alcohols such as methanol, ethanol, propanol and isopropanol, ethylene glycol derivatives such as ethylene glycol methyl ether, ethylene glycol ethyl ether and ethylene glycol butyl ether, and diethylene glycol methyl ether. Diethylene glycol derivatives such as diethylene glycol ethyl ether and diethylene glycol butyl ether, propylene glycol derivatives such as propylene glycol methyl ether, propylene glycol ethyl ether and propylene glycol butyl ether, acetic ester derivatives such as methyl acetate and ethyl acetate, lactic acid such as methyl lactate and ethyl lactate Water-soluble solvents such as ester derivatives and the like can be mentioned. It is selected from at least one or more kinds of water or water and a water-soluble solvent. Further, a part of an alcoholic solvent which is hardly soluble in water may be added. When water and a water-soluble solvent are used, the mixing ratio is 100 to 50% by weight of water and 0 to the water-soluble solvent.
-50, preferably 95-50% by weight of water, water-soluble solvent 5
~ 50% by weight.

Examples of the polymerization initiator include 2,2'-
Azo compounds such as azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), and 2,2'-azobis (isobutylvaleronitrile), tertiary butyl hydroperoxide, benzoylper Water-soluble polymerization initiators such as oxides, peroxides such as t-butyl peroxide, and persulfates such as ammonium persulfate and potassium persulfate can be used without particular limitation. The amount used is preferably 0.05 to 5 parts by weight based on 100 parts by weight of the total amount of the monomers. Also,
If necessary, the molecular weight of the binder can be controlled by using a chain transfer agent such as tashalidodecyl mercaptan or thioglycolic acid.

This reaction depends on the type of polymerization catalyst,
Usually, it can be performed at 40 to 90 ° C. Lower temperatures give higher molecular weight products and higher temperatures give lower molecular weight polymers.

The average weight molecular weight of the vinyl polymer used as the binder in the present invention is 100,000 to 100.
10,000, preferably 200,000 to 550,000. If it is less than 100,000, the mechanical properties of the green sheet cannot be sufficiently obtained,
If it exceeds 10,000, the fluidity of the binder resin will be low, and it will be difficult to obtain sufficient mechanical properties of the green sheet.

The particle size of the polymer obtained by the present invention can be measured by an electron microscope, a microtrack method or the like.

The ceramic powder used in the present invention having an average particle size of 50.0 microns or less is, for example, A
l ₂ O ₃ , SiO ₂ , 3Al ₂ O ₃ · SiO ₂ , PbO, Al
₂ O ₃ · MgO, B ₂ O ₃ , CaO, BaO, ZrO ₂ , ZnO,
At least 1 from Na ₂ O, P ₂ O ₅ , K ₂ O, Li ₂ O, etc.
It is selected from more than one species. More specifically, alumina (Al ₂ O ₃ ), mullite (3A)
l ₂ O ₃ · 2SiO ₂ ), cordierite (Cordie)
Rite, 2MgO.2Al ₂ O ₃ .5SiO ₂ ) at least one ceramic powder, SiO ₂ --B ₂ O _3-
Na _{2 O-based, SiO 2 -B 2 O 3 -K} 2 O based, SiO ₂ -B ₂
It is selected from at least one glass ceramic powder among borosilicate glasses such as O ₃ —Li ₂ O type and SiO ₂ —B ₂ O ₃ —ZnO type. Further, it is preferable that these glass ceramics are amorphous or crystalline glass ceramics that can be fired at a temperature lower than the melting point of copper, and a component in which cristobalite (Cristobalite) is hard to be generated after sintering is preferable. The ceramic fine particles used are spherical or pulverized. When fine through-hole processing is required, the average particle size of the ceramic powder for green sheets is generally 10 microns or less, more preferably 5 microns or less.

The ceramic raw material used in the present invention may be a high dielectric material such as BaTiO ₃ or a resistor material, and is not particularly limited.

Examples of the dispersion aid for ceramics used in the present invention include salts of polyacrylic acid such as ammonium polyacrylic acid and phosphate esters (Phosphate).
ester), polyethylene glycol, polyvinyl-
2-pyrrolidone and copolymer, glyceryl triole
(Glycerol trioleaste) and the like (Advaces in ceramics,
Vol. 21 、 Ceramic Powder Sci
ence p537-547, 1987).

The dispersion aid for ceramics makes it difficult for the ceramic powders to cohere with each other and facilitates the flow of the slurry. The dispersion aid for ceramics is used by adding ceramic powder to a solution obtained by dissolving or dispersing in a solvent (water, water and a water-soluble solvent). When used, wet mixing is carried out using a ball mill for 1 to 5 hours, then an organic binder for ceramics is added in a predetermined amount, and the ceramic precursor composition is wet mixed for at least 10 minutes using a ball mill.
You may do more than time.

The method for producing the ceramic precursor composition used in the present invention is as follows.
From 30 parts by weight of the (meth) acrylic resin suspension as a binder, which is the component (D), and from 30 parts by weight of the dispersion aid for ceramics, which is the component (E) if necessary. The ceramic precursor composition comprising the selected dispersant is wet-mixed for at least 5 hours using a ball mill to prepare a ceramic precursor composition slurry, which is subjected to a defoaming step, followed by extrusion molding and injection. Molding method, doctor
It is formed by a blade method, a calendar roll method, or the like. The manufacturing method is not particularly limited.

The method for producing the ceramic used in the present invention is the same as the method for producing the ceramic precursor composition obtained by the above-mentioned method.
It can be obtained by firing in air or a non-reducing atmosphere at a temperature of 50 to 1800 ° C. for at least 5 hours.

The multilayer ceramic substrate used in the present invention is obtained by the following manufacturing method. 100 parts by weight of the ceramic fine powder having an average particle size of 50.0 microns or less, which is the component (C), and 5 to 30 parts by weight of the (meth) acrylic resin suspension as a binder, which is the component (D). And, if necessary, a ceramic precursor composition comprising a ceramic powder and a dispersant selected from various ceramic dispersants, which is the component (E), is subjected to wet mixing for 5 to 50 by using a ball mill. After a time, the slurry is made into a ceramic precursor composition, a defoaming step is performed, and then a green sheet is formed by a doctor blade method or the like at a casting temperature of room temperature to 120 ° C. Greenness obtained as needed
In order to improve the mechanical properties of
You may dry at 30 degree C for 90 minutes at 0 degreeC. The obtained green sheet having a thickness of 0.05 to 2 mm is cut into a predetermined size (for example, 10 to 200 mm × 10 to 200 mm square), and a through hole is provided at a required layer and a predetermined position. Punch out. Although the diameter of the through hole is not limited,
A minimum of 40 microns is possible. On the punched green sheet, for example, W (melting point 3410 ° C.), M
o (melting point 2620 ° C.), Ag (melting point 961.9), Au
(Melting point 1064 ° C.), Pt (melting point 1769 ° C.), Pd
(Melting point 1554 ° C.), Cu (melting point 1083.4 ° C.), N
A conductor paste mainly composed of one or more conductors such as i (melting point 1453 ° C.) is printed at a predetermined position by the screen printing method. In this way, a predetermined circuit is formed on the green sheet in which the conductor is printed through a screen mask, and several to several tens of layers of the green sheet on which the circuit is formed are laminated at a temperature of 80 to 150 ° C. Pressure 0.98 MPa to 29.
Hot press bonding is performed at 4 MPa (10 to 300 kgf / cm ² ). The obtained laminated body is cut into a predetermined shape and size. The firing temperature varies depending on the type of conductor (generally below the melting point of the conductor).
A ceramic substrate is obtained by firing in air or a non-reducing atmosphere at a temperature of 50 to 1800 ° C. for at least 5 hours.

In order to manufacture a multilayer glass ceramic circuit board, the firing is carried out in air or in a non-reducing atmosphere at 350 to 450 ° C. in the temperature rising process, and then 600 to 90.
After baking at 0 ° C. to remove the binder, the volume ratio of hydrogen (H ₂ ) and steam (H ₂ O) is 10 to ⁷ to 10 to ⁴ or steam (steam A multilayer glass ceramic circuit board can be obtained by sintering at 900 ° C. to a temperature not higher than the melting point of the conductor in an atmosphere of (inert atmosphere controlled to a pressure of 0.005 to 0.5 atm).

The organic binder for molding a ceramic obtained by the present invention is composed of water alone or water and a water-soluble organic solvent, and it is not necessary to use a non-water-soluble organic solvent at all or hardly. It is possible to produce a ceramic green sheet that is excellent in dispersibility, surface smoothness, density, elongation, and strength, and has low pollution.
It is advantageous from the viewpoint of resource saving. Also, by laminating and firing the green sheets, a multilayer ceramic substrate that is dense and has excellent surface smoothness and strength can be obtained.

[0037]

The features of the present invention are that the above-mentioned ceramic forming organic binder is useful as an aqueous ceramic organic binder, and that the above-mentioned ceramic forming organic binder exerts its function to bond between the ceramic fine powders. It satisfies various characteristics of the sheet, that is, flexibility, moldability, dispersibility, and surface condition. Further, it satisfies various characteristics of the laminated body of the green sheet with circuit patterns, that is, the laminating pressure-bonding property, the mechanical strength and the like.

[0038]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited thereto.

The term “%” means “% by weight”.

100 parts by weight of ceramic powder and 5 to 30 parts by weight of an organic binder for forming ceramics were added to obtain a ceramic precursor composition. This was kneaded with a ball mill. After the ceramic precursor composition slurry was prepared in this manner, air was further degassed from the slurry under reduced pressure. Adjusting the viscosity of the uniform slurry mixture prepared in this way, using a doctor blade type casting device,
It was coated on a polyester film and dried to produce a green sheet. Various physical properties of the sheet include moldability, flexibility,
The dispersibility was evaluated.

(Moldability) After being coated on a polyester film and dried, it was visually evaluated.

Good: Peeling of the green sheet from the polyester sheet is good and there is no crack.

Δ: A green sheet with some cracks.

X: Do not crack to form a green sheet.

(Flexibility) The central portion of the green sheet was held down by each of five types of glass core rods having different diameters, and a bending test of 180 ° centered on each was performed. Flexibility was indicated by the diameter (mmφ) of the core rod immediately before the sheet was cracked. The diameter of the core rod is 2, 3, 4, 6, 8 mm.

(Dispersibility) ◯: Secondary aggregation is small in the dispersed state of the ceramic fine particles in the green sheet.

Δ: The secondary agglomeration is slightly large in the dispersion state of the ceramic fine particles in the green sheet.

X: A large amount of secondary agglomeration occurs in the dispersed state of the ceramic fine particles in the green sheet.

Example 1 (Synthesis of Organic Binder for Ceramic Molding) A 5 l flask equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel and a gas introducing tube was charged with ion-exchanged water 1 under a nitrogen gas stream.
100 g was charged, and 100 g of polyethylene glycol (average molecular weight: 250,000 to 300,000) was dispersed therein and heated with stirring to obtain an aqueous solution of polyethylene oxide. While heating this aqueous solution at 60 ° C. and stirring vigorously, 800 g of butyl methacrylate and 200 g of n-butyl acrylate were used.
1 g of a mixed solution of 20 g of azobisisobutyronitrile
The solution was uniformly added dropwise over a period of time and heated at 60 ° C. for 4 hours.
This was cooled to room temperature to obtain a ceramics forming organic binder having a solid content concentration of 50%.

(Production of Green Sheet) Alumina powder as a main component, Al ₂ O ₃ 91% as a whole composition,
A ceramic precursor composition was obtained by adding 100 parts by weight of a ceramic powder having a particle size of 5 μm or less and having 6% of SiO ₂ and 3% of MgO and 20 parts by weight of an organic binder for forming a ceramic. This was kneaded for 24 hours in a ball mill using an alumina lining container and alumina balls. After the ceramic precursor composition slurry was prepared in this manner, air was further degassed from the slurry under reduced pressure. The viscosity of the thus-prepared uniform slurry mixed solution was adjusted to 5,000 to 10,000 cps, and it was coated on a polyester film using a doctor blade type casting device and dried at 120 ° C. to produce a green sheet. did. As shown in Table 1, various physical properties of the sheet include moldability,
Both flexibility and dispersibility were good.

(Preparation of Multilayer Wiring Ceramic Substrate) A green sheet is punched with a die of 200 mm × 200 m.
It was cut into m-squares and provided with guide holes. Then, the green sheet was fixed using the holes for the guide, and a through hole having a diameter of 0.1 mm was punched out at a predetermined position by a punch method. Tungsten powder having a particle size of 5 μm or less: Nitrocellulose: Ethylcellulose: α-Terpineol = 1
A conductor paste of 00: 4: 2: 23 (weight ratio) was filled in the through holes formed in the green sheet, and then a predetermined circuit pattern was printed on the surface of the green sheet by a screen printing method. The conductor was printed in this way, and 40 sheets of green sheets having a circuit formed were laminated by aligning the positions of the guide holes, and hot press bonding was performed at 120 ° C. and a pressure of 100 kgf / cm ² . The obtained laminated body was cut into a required shape to obtain a 150 mm × 150 mm square green sheet laminated plate, which was fired at 1600 ° C. for 2 hours in a nitrogen-hydrogen-steam mixed atmosphere firing furnace. During firing, the binder was sufficiently removed during the temperature rising process. By this green sheet laminating method, a multilayer wiring ceramic substrate of 120 mm × 120 mm square and 7 mm thick was produced.

Examples 2 to 10 (Synthesis of Organic Binder for Ceramic Molding) Table 1 shows the types and amounts of water-soluble polymers, the compounding ratio of monomers, the types and amounts of polymerization initiators, and the types and amounts of dispersion media. An experiment was performed in the same manner as in Example 1 except that the organic binder was used for ceramic molding, except that the organic binder was changed as shown.

(Production of Green Sheet) Example 1 except that the organic binder for ceramic molding and the addition amount thereof were changed.
Perform an experiment in the same manner as above to make a green sheet,
The various properties are shown in Table 1.

(Production of Multilayer Wiring Ceramic Substrate) An experiment was conducted in the same manner as in Example 1 to produce a multilayer wiring ceramic substrate from a green sheet.

Examples 11 to 26 (Synthesis of Organic Binder for Ceramic Molding) Table 2 shows the types and amounts of water-soluble polymers, the compounding ratio of monomers, the types and amounts of polymerization initiators, and the types and amounts of dispersion media. An experiment was conducted in the same manner as in Example 1 except that the organic binder was changed to the one shown in No. 3 to obtain an organic binder for ceramic molding.

(Preparation of Green Sheet) Alumina powder as a main component, Al ₂ O ₃ 33% as a whole composition,
100 parts by weight of a ceramic powder having a particle size of 5 μm or less, containing 33% SiO _{2 and} 34% borosilicate glass,
The organic binder for ceramic molding 5
30 parts by weight were added to obtain a ceramic precursor composition. This was kneaded for 24 hours in a ball mill using an alumina lining container and alumina balls. Hereinafter, an experiment was conducted in the same manner as in Example 1 to produce a green sheet, and its characteristics are shown in Tables 2 and 3.

(Preparation of Multilayer Wiring Ceramic Substrate) The firing temperature is 350 to 840 ° C. and the firing temperature is 95 after 20 hours.
An experiment was conducted in the same manner as in Example 1 except that the main firing was changed to 0 ° C. for 2 hours, and a multilayer wiring ceramic substrate was produced from the green sheet.

Example 27 (Synthesis of Organic Binder for Ceramic Molding) A 2 l flask equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel and a nitrogen gas introducing tube was charged with ion-exchanged water 742. 7 g, water-soluble high molecular weight polyethylene oxide (hereinafter abbreviated as PEO, average molecular weight; 250,000 to 300,000) 2
8.5 g was added with stirring, dissolved uniformly, and purged with nitrogen gas for 30 minutes. While stirring, butyl methacrylate 300 g, plasticizer diisononyl phthalate 31.5
g, and a polymerization initiator of 0.45 g of ammonium persulfate were added, and the nitrogen gas was replaced in 30 minutes to 1 hour. The polymerization temperature was continuously heated at 60 ° C. for 4 hours, and the polymerization was further performed at 80 ° C. for 2 hours to complete the reaction. This was cooled to room temperature to obtain a ceramics forming organic binder having a solid content concentration of 32% [polymer 50% average particle diameter; 3.0 microns, suspension viscosity; 7 Pa · s, weight average molecular weight; 500,000]. . (Preparation of Green Sheet) Alumina powder as a main component, Al ₂ O ₃ 91%, SiO ₂ 6 as a whole composition
%, MgO 3%, 100 parts by weight of ceramic powder having a particle size of 5 microns or less, 40 parts by weight of ion-exchanged water, ceramic dispersant A6114 (trade name, solid content 40
%, Manufactured by Toa Gosei Kagaku Co., Ltd.) and kneaded for 2 hours in a ball mill using an alumina liner and alumina balls. Further, 20 parts by weight of a ceramic forming organic binder was added to obtain a ceramic precursor composition. This was kneaded for 24 hours in a ball mill using an alumina lining container and alumina balls. After the ceramic precursor composition slurry is prepared in this manner, the slurry is further depressurized at 133.3 Pa to 6665.
Degassing was performed under Pa (1 mmHg to 50 mmHg). The uniform slurry mixture prepared in this manner is further adjusted to a viscosity of 3 Pa · s to 10 P while scattering water under reduced pressure.
a ・ s, using a doctor blade type casting device,
Casting on polyester film at 120 ℃
And dried to prepare a green sheet having a thickness of 0.2 mm. As shown in Table 4, the physical properties of the sheet were good in terms of moldability, flexibility and dispersibility.

(Fabrication of Multilayer Wiring Ceramic Substrate) The obtained green sheet was punched with a die of 200 mm ×
It cut into a 200 mm square and provided a hole for a guide. Then, the green sheet was fixed using the holes for the guide, and a through hole having a diameter of 0.1 mm was punched out at a predetermined position by a punch method. Tungsten powder with a particle size of 5 microns or less: Nitrocellulose: Ethylcellulose: α-Terpineol = 100: 4: 2: 23 (weight ratio) is filled in the through holes formed in the green sheet and then screen-printed. The circuit pattern was printed on the surface of the green sheet. The conductor is printed in this way, and 40 sheets of the green sheet on which a circuit is formed are stacked with the positions of the guide holes aligned, and the temperature is 120 ° C and the pressure is 9.80.
Hot press bonding was performed at MPa (100 kgf / cm ² ). The resulting laminate is cut into the required shape and
mm × 150 mm square green sheet laminate, nitrogen-hydrogen-steam (pressure ratio; 0.6 atm: 0.2 atm:
It was fired at 1600 ° C. for 2 hours in a mixed atmosphere firing furnace (0.2 atm). During firing, the binder was sufficiently removed during the temperature rising process. By this green sheet lamination method, 120
A multilayer wiring ceramic substrate having a size of 120 mm square and a thickness of 7 mm was produced.

[Examples 28 to 37] Table 4 shows the composition and amount of the binder used in Examples 27 and 28 to 37, the evaluation results of various properties of the green sheet, and the like.

(Synthesis of Organic Binder for Ceramic Molding) In Examples 28 to 30, the compounding ratio of the component (A) and the component (B) was 300 g of the component (A), and PEO as the component (B) was added. The amounts were 24 g, 21 g, and 15 g, respectively. The ion-exchanged water was 733.1 g and 726.8 g, respectively.
g, 718.0 g. In addition, in Examples 31 to 33,
(A) Component vinyl monomer type (constant mixing ratio),
The solid content was the same as in Example 27 except that the type and the amount of the viscosity average molecular weight of the component (B) were changed, and the mixing ratios of water and the water-soluble solvent were changed in Examples 34 to 37. An organic binder for forming ceramics having a concentration of 32% by weight was obtained.

(Production of Green Sheet) An experiment was conducted in the same manner as in Example 27 except that the organic binder for ceramic molding and the addition amount thereof were changed to produce a green sheet, and various characteristics of the green sheet are shown in Table 4. Indicated.

(Production of Multilayer Ceramic Substrate) Example 27
An experiment was conducted in the same manner as described above, and a multilayer wiring ceramic substrate was produced from the green sheet.

[Examples 38 to 54] Table 5 shows the evaluation of various kinds of binder compositions (A) component, (B) component, plasticizer and polymerization initiator, and their amounts, and various properties of the green sheet. The results are shown.

(Synthesis of Organic Binder for Ceramic Molding) Except that the kinds and amounts of the components (A), (B), plasticizer, polymerization initiator and water-soluble solvent were changed as shown in Table 5. In the same manner as in Example 1, an organic binder for ceramics molding having a solid content concentration of 32% by weight was obtained.

(Production of Green Sheet) Borosilicate glass (79% SiO ₂ , B ₂ O ₃ ) for glass ceramics
19%, K ₂ O 2%) 65vol%, alumina 15vo
100 parts by weight of a ceramic powder having a particle size of 5.0 micron or less and having a component of 1% and cordierite of 20% by volume, 0.16 parts by weight of A6114 (described above), and 40 parts by weight of deionized water are added to the ball mill. Mixing was carried out for 2 hours, and 30 parts by weight of 10 parts by weight of the organic binder for ceramic molding shown in Table 2 was added thereto to obtain a ceramic precursor composition. An experiment was carried out in the same manner as in Example 27 to produce a green sheet, and its various properties are shown in Table 5.

(Production of Multilayer Ceramic Substrate) The obtained green sheet was punched with a die of 200 mm × 20.
It was cut into 0 mm square and provided with a guide hole. Then, the green sheet was fixed using the holes for the guide, and a through hole having a diameter of 0.1 mm was punched out at a predetermined position by a punch method.

89% by weight of copper powder having a particle size of 3 microns or less,
Vehicle (solvent; n-butyl carbitol acetate 9
0 to 95% by weight, binder: ethyl cellulose 5 to 10
The green sheet having the through holes formed therein was filled with a conductor paste composed of 11 wt% of the weight percent), and then a predetermined circuit pattern was printed on the surface of the green sheet by the screen printing method. The conductors are printed in this way, and 40 green sheets on which a circuit has been formed are laminated by aligning the positions of the holes for guides, and the temperature is 120 ° C and the pressure is 9.80 MPa (100 kgf / 100 kgf /
The heat press bonding was carried out at cm ² ). The obtained laminated body is cut into a required shape to form a 150 mm × 150 mm square green sheet laminated plate, and nitrogen-hydrogen-steam (pressure ratio; 0.65 atm: 1 × 10 to ⁴ atm: 0.35 atm)
After debinding at 350 to 850 ° C. for 20 hours in the atmosphere, firing was performed at 950 ° C. for 2 hours in the nitrogen atmosphere. During firing, the binder was sufficiently removed during the temperature rising process. By this green sheet lamination method, 120 mm x 120 mm square,
A multilayer wiring ceramic substrate having a thickness of 7 mm was produced.

Comparative Example 1 (Binder Resin) A polyvinyl acetate-based copolymer containing 4.0 mol% of octylacrylamide and 2.0 mol% of trimethyl-3- (1-methacrylamidopropyl) ammonium chloride. , Its vinyl acetate component 8
A modified PVA in which 8.7 mol% was saponified and the viscosity of a 4% aqueous solution at 20 ° C. was 34 centipoise was used as a binder.

(Preparation of green sheet) Alumina powder was the main component, and the total composition was Al ₂ O ₃ 33%, S
100 parts by weight of ceramic powder having a particle size of 5 micron or less having 33% of io _{2 and} 34% of borosilicate glass, 6 parts of the binder resin, 1 part of polyoxyethylene nonylphenol ether as a dispersant, and 5 parts of ion-exchanged water.
0 parts were added together to obtain a ceramic precursor composition. This was kneaded for 24 hours in a ball mill using an alumina lining container and alumina balls. Experiments were performed in the same manner as in Example 1 to produce a green sheet, and various properties are shown in Table 8.

Comparative Example 2 (Binder Resin) Acrylic acid, butyl acrylate, ethyl acrylate Polymerization ratio (50/25/25) Monoethanolamine salt 20 of copolymer having a weight average molecular weight of about 100,000
Water / methanol polymerization ratio (5/5) of 80 g
Emulsion polymerization of ethyl acrylate with 0.4 g of ammonium persulfate as a polymerization initiator in a mixed solvent of g to give a solid content of 50
% Latex was obtained.

(Production of Green Sheet) Comparative Example 1 except that 24 parts of the latex and 18 parts of ion-exchanged water were used.
Perform an experiment in the same manner as above to make a green sheet,
The various characteristics are shown in Table 7.

Comparative Example 3 (Binder Resin) A latex having a composition of butyl acrylate, acrylic acid, and methacrylic acid polymerization ratio (70/15/15) as a dispersant and a nonionic surfactant as an emulsifier was obtained. It was

(Preparation of Green Sheet) An experiment was conducted in the same manner as in Comparative Example 1 except that 10 parts of the latex (solid content), monoethanolamine as the neutralizing agent and 25 parts of ion-exchanged water were used. Was prepared, and its various characteristics are shown in Table 7.

Comparative Example 4 (Binder Resin) 4 parts by weight of glycine betaine chloride chloride of polyoxyethylene octyl phenyl ether,
Polyoxypropylene polyoxyethylene glycol dimethacrylate 4 parts by weight was used as an emulsifier, 2,2'-azobis (N, N'-dimethyleneisobutylamidine) hydrochloride was used as a polymerization initiator, and ethyl acrylate was 75 parts by weight. A latex having a composition of 75 parts by weight of methyl methacrylate and 4.5 parts by weight of N-methylol acrylic acid amide was obtained.

(Preparation of Green Sheet) 10 parts of the latex (solid content), 3 parts of polyethylene glycol (molecular weight 200) as a plasticizer and 2 parts of ethyl carbitol.
Part and 25 parts of ion-exchanged water were used, an experiment was conducted in the same manner as in Comparative Example 1 to produce a green sheet, and its various properties are shown in Table 7.

Comparative Example 5 (Binder Resin) Aqueous Dispersion of Hydrophobic Polymer as Component (B): Methacrylic Acid Ester (MMA / n-BMA /
LMA / CHMA = 10/60/10/20, solid content 4
8%) emulsion and 10% water-soluble polymer PVA (A) (polymerization 500, saponification degree 88.5 mol%)
Were mixed at a 1/1 weight ratio to obtain an organic binder for green sheets (composite binder).

(Production of Green Sheet) Alumina powder as a main component and Al ₂ O ₃ 33% in total composition, S
100 parts by weight of a ceramic powder having a particle size of 5 μm or less and containing 33% of io _{2 and} 34% of borosilicate glass,
The latex 16 parts (solid content), 50 parts by weight of water, and 0.3 part of a polyacrylic acid ammonium salt dispersion aid were mixed in a ball mill for 2 hours, and then a composite binder was added in a solid content of 1 part.
Except that 0 parts was added and the mixture was uniformly mixed with the powder. An experiment was conducted in the same manner as in Comparative Example 1 to produce a green sheet, and its various properties are shown in Table 7.

However, the abbreviations in Tables 1, 2, 3, 4, 5, 6, 7 are as follows.

PEO: polyethylene oxide, PEt
OZO: poly (2-ethyloxazoline), PVP: polyvinyl-2-pyrrolidone, n-BMA: n-butyl methacrylate, i-BMA: isobutyl methacrylate, n-BAA: n-butyl acrylate, MAA: methyl acrylate, HEMA: 2- Hydroxyethyl methacrylate, St: styrene, EAA: ethyl acrylate, EMA: ethyl methacrylate, HEA: hydroxyethyl acrylate, i-Bt: isobutylene,
i-BMA: isobutyl methacrylate, BzMA: benzyl methacrylate, MMA: methyl methacrylate, HPMA: hydroxypropyl methacrylate, α
-St: α-methylstyrene, MEAA: methoxyethyl acrylate, MAA: methyl acrylate, LM
A: lauryl methacrylate, CHMA: cyclohexyl methacrylate, PGM: propylene glycol monomethyl ether, PGE: propylene glycol monoethyl ether, ML: methyl lactate, IPA: isopropyl alcohol, AIBN: 2,2′-azobis (isobutyronitrile), APS: ammonium persulfate, KP
S: Potassium persulfate, t-BHPO: Tertiary butyl hydroperoxide Examples 1, 5, 12, 14, 15, 18, 19,
20, 21, 24, 27, 31, 34, 39, 40, 4
3, 44, 46, 49, 52 and the organic binders obtained in Comparative Examples 1 to 5 were put in a platinum crucible, ashed in a 600 ° C. electric furnace in a nitrogen atmosphere for 3 hours, and the weight was measured. . In addition, the five green sheets obtained in Examples 1, 5, 27, 31, and 34 were heated at 120 ° C. and 100 kgf / c.
Hot press bonding was performed at m ² . The number of peelings at this time was visually observed. Furthermore, in a nitrogen-hydrogen-steam (pressure ratio; 0.6 atm: 0.2 atm: 0.2 atm) atmosphere, 1
The ceramic sheet was obtained by firing at 600 ° C. for 2 hours. Examples 12, 14, 18, 19, 20, 21, 24, 3
9, 40, 43, 44, 46, 49, 52 and Comparative Example 1
5 green sheets obtained in ~ 5, 120 ℃, 100
Hot press compression was performed at kgf / cm ² . The number of peelings at this time was visually observed. Furthermore, this laminated body was subjected to nitrogen-hydrogen-steam (pressure ratio: 0.65 atm: 1 × 10 ⁴
Atmospheric pressure: 0.35 atm) in an atmosphere of 350 to 850 ° C., 2
After binder removal for 0 hours, calcination was performed at 950 ° C. for 2 hours in a nitrogen atmosphere. The density of these sheets was measured, and the surface condition was visually observed. The results are shown in Table 8.

[0081]

[Table 1]

[0082]

[Table 2]

[0083]

[Table 3]

[0084]

[Table 4]

[0085]

[Table 5]

[0086]

[Table 6]

[0087]

[Table 7]

[0088]

[Table 8]

[0089]

Industrial Applicability The organic binder for ceramic molding obtained by the present invention is a ceramic excellent in dispersibility of ceramics, surface smoothness, density and mechanical strength without using a water-insoluble organic solvent at all. A green sheet can be produced, which is advantageous from the viewpoint of low pollution and resource saving. Especially in the doctor blade method,
It is possible to transfer from an organic solvent system to a safe and sanitary water system, and has excellent properties such as improved mechanical strength, and is useful as a binder for ceramics.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masasaku Ishihara, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa, Ltd. Production Engineering Research Laboratory, Hitachi, Ltd. (72) Inventor, Takeshi Fujita, Horiyamashita, Hadano, Kanagawa Hitachi, Ltd. General-purpose computer division (56) Reference JP-A-60-122770 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C04B 35/632 C04B 35/00-35/50

Claims (11)

(57) [Claims] 1. (A) 100 parts by weight of a polymer of at least one vinyl monomer and (B) an average viscosity molecular weight of 25.
10,000 to 1.1 million polyethylene oxide or poly (2
-Ethyloxazoline ) 1 to 9.5 parts by weight and water or water and a water-soluble organic solvent, and an organic binder for ceramic molding. 2. An organic binder for ceramic molding, wherein the polymer of the vinyl monomer as the component (A) according to claim 1 is a (meth) acrylic acid ester type. 3. The (A) component (meta) according to claim 2.
Acrylic ester polymer ester has 1 carbon atom
An organic binder for ceramic molding, which is an ester of 18 alkyl groups and / or cyclic alkyl groups and / or aryl groups having 3 to 12 carbon atoms. 4. The component (A) according to claim 2, which is (meth).
Acrylic ester polymer ester has 1 carbon atom
An organic binder for ceramic molding, which is an ester of 18 alkyl groups and / or cyclic alkyl groups having 3 to 12 carbon atoms and / or aryl groups and an ester of hydroxyalkyl groups. 5. The component (A) according to claim 1, wherein the ester of the (meth) acrylic acid ester-based polymer has a carbon number of 1 to 1.
From 50% or more of an ester of 18 alkyl groups or / and a cyclic alkyl group or / and an aryl group of 3 to 12 carbon atoms and a hydroxyalkyl group, and 50% or less of a vinyl-based monomer copolymerizable therewith An organic binder for ceramic molding, which is characterized by: 6. At least one type of component (A)
100 parts by weight of the vinyl monomer and the average of the component (B)
Polyethylene oxide having a viscosity of 250,000 to 1.1 million
Or poly (2-ethyloxazoline) 1-9.5 weight
In water or a mixed liquid of water and a water-soluble organic solvent,
The component (A) is suspended (co) polymerized in the presence of a polymerization initiator.
Of an organic binder for ceramic molding characterized by
Manufacturing method. 7. (C) 100 parts by weight of ceramic powder,
(D) A ceramic precursor composition comprising 5 to 30 parts by weight of the binder according to claim 1 . 8. (C) 100 parts by weight of ceramic powder,
(D) a ceramic, characterized in that formed by sintering a ceramic precursor composition comprising a server Indah 5-30 parts by weight of claim 1. 9. A (C) ceramic average particle size of less 50.0 microns powder 100 parts by weight, (D) according to claim 1
A ceramic green sheet comprising a thin film of the ceramic precursor composition comprising 5 to 30 parts by weight of the binder described in 1 . 10. A (C) ceramic powder 100 parts by weight average particle diameter is less than 50.0 microns, (D) according to claim
Se <br/> La Mick sheet characterized by being obtained by sintering a ceramic green sheet composed of a binder 5 to 30 parts by weight of the described 1. 11. A ceramic green sheet layer comprising (C)
A ceramic precursor composition comprising 100 parts by weight of a ceramic fine powder having an average particle size of 10.0 microns or less and (D) 5 to 30 parts by weight of the binder according to claim 1, and a plurality of ceramic precursor compositions. A conductor layer is laminated with the ceramic green sheet layer interposed therebetween , and the laminate is sintered.
A multilayer wiring ceramic substrate characterized in that .