KR101805226B1 - Binder resin for sintering, method for producing same, paste composition, and inorganic sintered compact - Google Patents

Abstract

(A-1), 60 to 99.8 mass% of an alkyl (meth) acrylate (A-1), 0.1 to 5 mass% of a compound (A-2) having two or more radically polymerizable unsaturated double bonds, , 0.1 to 30 mass% of a monomer other than the compound (A-2) having at least two radically polymerizable unsaturated double bonds and 0 to 39.8 mass% of other copolymerizable monomer (A-4) A 15 mass% solution of the resin obtained by dissolving the resin in terpineol as a firing binder resin obtained by copolymerizing the mixture (A) has a? ₁ /? ₁₀ of less than 2.5 and a? ₁ /? ₅₀₀₀ of 5 Resins satisfying the above conditions.

Description

TECHNICAL FIELD [0001] The present invention relates to a firing binder material, a method for producing the same, a paste composition, and an inorganic sintered material,

The present invention relates to a method for producing a firing binder material used for shaping inorganic powders such as a metal powder, a metal oxide powder, a fluorescent powder and a glass frit, a binder material obtained therefrom, ≪ / RTI >

The present application claims priority based on Japanese Patent Application No. 2010-106439 filed on May 6, 2010, the contents of which are incorporated herein by reference.

In the field of electronic materials and the like, a molded body made of an inorganic material or a pattern (for example, a wiring pattern, an insulating pattern, etc.) formed by the molded body is sometimes used. As a method for forming such a molded product or a pattern, an inorganic powder such as a metal powder, a metal oxide powder, a fluorescent powder or a glass frit is mixed with a binder resin to prepare a paste composition, And then firing to thermally decompose the binder resin.

The binder resin used at this time plays a role of catching the inorganic powder so as not to be damaged at the time of improvement in workability or movement during molding. Since the binder resin is removed by thermal decomposition at the time of sintering the inorganic powder before it becomes a final product, it is required that the binder resin has high thermal decomposability and excellent workability at the time of each processing.

Examples of the processing method of the paste composition include a screen printing method, a method of molding into a sheet form by a doctor blade, a dipping method, a dispensing method, and the like.

Among them, when the screen printing method is applied, the higher the thixotropy property in the high-shear region of the paste composition, the better the printability. Further, in the leveling property after printing, the lower the thixotropy property in the low-shear region, the better. Therefore, when screen printing is performed, it is required that the thixotropy property of the paste composition be high in the high shear region and low in the low shear region.

With respect to this demand, Patent Document 1 proposes a binder resin obtained by polymerizing an alkyl (meth) acrylate, a compound having two or more radically polymerizable unsaturated double bonds and a hydroxyl group-containing (meth) acrylate .

Further, Patent Document 2 discloses that at least two or more kinds of methacrylic acid alkyl ester monomers are mixed with 90 to 99% by weight of an unsaturated carboxylic acid monomer, an amino group-containing (meth) acrylic acid alkyl ester monomer, a hydroxyl group-containing (meth) And 0.1 to 5 wt% of at least one member selected from the group consisting of polyfunctional (meth) acrylic acid alkyl ester monomers, and 0.001 to 0.1 wt% of a polyfunctional (meth) acrylic acid alkyl ester monomer.

Japanese Patent Application Laid-Open No. 2003-183331 Japanese Patent Application Laid-Open No. 2004-217686

However, even in the paste composition using the binder resin described in Patent Document 1, it is difficult to satisfactorily satisfy both the leveling property and the printability in screen printing.

In addition, the paste composition using the binder resin described in Patent Document 2 has a low thixotropic property and is not suitable for screen printing.

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances and has as its object to provide a paste composition excellent in leveling properties and printability in screen printing, a firing binder resin for easily obtaining the paste composition, And an object of the present invention is to provide an inorganic sintered body.

(1) an alkyl (meth) acrylate (A-1) in an amount of 60 to 99.8% by mass,

0.1 to 5% by mass of a compound (A-2) having at least two radically polymerizable unsaturated double bonds,

0.1 to 30% by mass of a water-soluble unsaturated monomer (A-3) (provided that it is a monomer other than the compound (A-2) having two or more radically polymerizable unsaturated double bonds)

0 to 39.8 mass% of other copolymerizable monomer (A-4)

(A), wherein the 15% by mass solution of the resin obtained by dissolving the resin in terpineol satisfies the following conditions.

When? ₁ /? ₁₀ is less than 2.5

η ₁ / η ₅₀₀₀ is 5 or more

Here, eta ₁ , eta ₁₀ and eta ₅₀₀₀ are measured using a viscoelasticity measuring device (Physca MCR300, manufactured by Anton Paar) at a cone plate of 0.5 deg. / 25 mm and a measurement temperature of 23 deg. a viscosity, η ₁ is the time of a shear rate of 1 (1 / s) viscosity, η ₁₀ of when the shear rate of 10 (1 / s) viscosity when, η ₅₀₀₀ is a shear rate of 5000 (1 / s) Viscosity.]

[2] 35 to 99.7 mass% of alkyl (meth) acrylate (a-1)

0.3 to 5% by mass of a compound (a-2) having two or more radically polymerizable unsaturated double bonds,

0 to 40% by mass of a water-soluble unsaturated monomer (a-3) (provided that it is a monomer other than the compound (a-2) having two or more radically polymerizable unsaturated double bonds)

Other monomer (a-4) 0 to 64.7 mass%

In the presence of a first polymer obtained by radical polymerization of a monomer mixture (1)

35 to 99.9% by mass of alkyl (meth) acrylate (b-1)

0 to 1% by mass of a compound (b-2) having at least two radically polymerizable unsaturated double bonds,

0.1 to 30% by mass of a water-soluble unsaturated monomer (b-3) (provided that it is a monomer other than the compound (b-2) having two or more radically polymerizable unsaturated double bonds)

Other monomer (b-4) 0-64.9 mass%

And a second polymer obtained by radical polymerization of the monomer mixture (2) containing the first monomer and the second monomer.

[3] The resin according to [1] or [2], wherein the firing binder resin is a particle having a volume average particle diameter of 100 μm or less.

[4] A paste composition comprising the binder resin for firing, inorganic powder and organic solvent according to any one of [1] to [3].

[5] An inorganic sintered body obtained by firing the paste composition according to [4].

[6] A composition comprising 35 to 99.7% by mass of an alkyl (meth) acrylate (a-1)

0.3 to 5% by mass of a compound (a-2) having two or more radically polymerizable unsaturated double bonds,

0 to 40% by mass of a water-soluble unsaturated monomer (a-3) (provided that it is a monomer other than the compound (a-2) having two or more radically polymerizable unsaturated double bonds)

Other monomer (a-4) 0 to 64.7 mass%

A first polymerization step of radical-polymerizing the monomer mixture (1)

In the presence of the first polymer,

35 to 99.9% by mass of alkyl (meth) acrylate (b-1)

0 to 1% by mass of a compound (b-2) having at least two radically polymerizable unsaturated double bonds,

0.1 to 30% by mass of a water-soluble unsaturated monomer (b-3) (provided that it is a monomer other than the compound (b-2) having two or more radically polymerizable unsaturated double bonds)

Other monomer (b-4) 0-64.9 mass%

And a second polymerization step of radical polymerizing the monomer mixture (2) containing the monomer mixture (2) to obtain a second polymer.

By using the firing binder resin of the present invention, a paste composition excellent in both leveling property and printability in screen printing can be easily obtained.

Further, according to the method for producing a firing binder resin of the present invention, it is possible to produce a firing binder resin which can easily obtain a paste composition excellent in leveling property and printability in screen printing.

Further, the paste composition of the present invention is excellent in leveling property and printability in screen printing.

Hereinafter, the present invention will be described in detail.

In the present specification, (meth) acrylate represents both acrylate and methacrylate, and (meth) acrylic acid represents both acrylic acid and methacrylic acid.

(Firing binder resin and method for producing the same)

The firing binder resin of the present invention contains 60 to 99.8 mass% of an alkyl (meth) acrylate (A-1) (hereinafter referred to as "(A-1) component"), two or more radically polymerizable unsaturated double bonds 0.1 to 5% by mass of the compound (A-2) (hereafter, referred to as "component (A-2)") and the water-soluble unsaturated monomer (A- To 30% by mass of a copolymerizable monomer (A-4), and 0 to 39.8% by mass of another copolymerizable monomer (A-4) As a preferable production method, the following methods can be mentioned.

35 to 99.7% by mass of an alkyl (meth) acrylate (a-1) (hereinafter referred to as "component (a-1)"), and a compound (a-2) having two or more radically polymerizable unsaturated double bonds (A-2) having at least two radically polymerizable unsaturated double bonds (hereinafter referred to as "component (a-2)"), 0.3 to 5 mass% (Hereinafter referred to as "component (a-3)") 0 to 40 mass%, and other monomer (a-4) % Of the monomer mixture (1) is subjected to radical polymerization to obtain a first polymer;

(Meth) acrylate (b-1) (hereinafter referred to as "component (b-1)") in the presence of the first polymer in the presence of at least two radically polymerizable unsaturated double bonds , A water-soluble unsaturated monomer (b-3) (provided that at least two of the radically polymerizable unsaturated double bonds are contained in the compound (b-2) (hereinafter referred to as " component (b-3) ") and 0.1 to 30 mass% of other monomer (b- (Hereinafter referred to as " a second polymerization step ") in which a monomer mixture (2) containing 0 to 64.9 mass% is subjected to radical polymerization to obtain a second polymer

And a binder resin for firing.

≪ Monomer mixture (A) >

The monomer mixture (A) includes the component (A-1), the component (A-2) and the component (A-3).

(A-1) is an alkyl (meth) acrylate. As the component (A-1), an alkyl (meth) acrylate having an alkyl group of 1 to 8 carbon atoms is preferable. Specific examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, butyl And mono (meth) acrylates such as 2-ethylhexyl (meth) acrylate. The component (A-1) may be used alone or in combination of two or more.

The mass ratio of the component (A-1) in the monomer mixture (A) is 60 to 99.8 mass% based on 100 mass% of the monomer mixture (A). (A-1) is 60 to 99.8 mass%, excellent firing can be imparted to the firing binder resin to be obtained, and the firing resin can be suitably used as a firing member. The lower limit of the proportion of the component (A-1) is preferably 65% by mass or more, and more preferably 70% by mass or more.

(A-2) is a compound having two or more radically polymerizable unsaturated double bonds. Examples of the component (A-2) include ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,3-butyleneglycol methacrylate, Di (meth) acrylic acid neopentyl glycol, hydroxypivalic acid neopentyl glycol di (meth) acrylate ester, di (meth) acrylate polypropylene glycol, di (meth) (Meth) acrylic acid ester, propoxylated trimethylolpropane tri (meth) acrylate ester, ethoxylated trimethylolpropane tri (meth) acrylate ester, propoxylated trimethylolpropane tri (meth) , Glycerin tri (meth) acrylate, ethoxylated glycerine tri (meth) acrylate, and dipentaerythritol hexa (meth) acrylate . These are particularly preferable because they are excellent in the balance between the viscosity increasing effect and the thermal decomposability and are hard to cause cobwebbing even if the viscosity is increased. The component (A-2) may be used alone or in combination of two or more.

The mass ratio of the component (A-2) in the monomer mixture (A) is 0.1 to 5 mass% based on 100 mass% of the monomer mixture (A). And the content of the component (A-2) is from 0.1 to 5% by mass, the viscosity of the paste composition containing the obtained firing binder resin can be improved to improve the printing property and can be suitably used as a firing agent.

The lower limit of the ratio of the component (A-2) is preferably 0.5% by mass or more. When the proportion of the component (A-2) is 0.5% by mass or more, the balance between the viscosity increasing effect and the thermal decomposability is improved, and excellent printability in screen printing can be imparted. On the other hand, the upper limit of the ratio of the component (A-2) is preferably 3% by mass or less in view of the solubility in an organic solvent.

(A-3) is a water-soluble unsaturated monomer other than the component (A-2). (Meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and the like. (Meth) acrylate, 4-hydroxybutylacrylate, acrylamide, maleic acid, and fumaric acid. The component (A-3) may be used alone or in combination of two or more.

The mass ratio of the component (A-3) in the monomer mixture (A) is 0.1 to 30 mass% based on 100 mass% of the monomer mixture (A). When the ratio of the component (A-3) is 0.1% by mass or more, the viscosity of the paste composition containing the obtained firing binder resin can be improved to improve the printability and provide excellent leveling properties. Further, when the paste composition is used, the dispersion stability of the inorganic powder can be improved. And the proportion of the component (A-3) is 30% by mass or less, the firing property of the firing binder resin can be improved.

The monomer mixture (A) may contain the component (A-4) in addition to the components (A-1), (A-2) and (A-3)

Examples of the component (A-4) include styrene,? -Methylstyrene, acrylonitrile, diethylaminoethyl methacrylate, vinyl acetate and the like. The kinds of these radical polymerizable monomers are appropriately selected depending on the kinds of inorganic powders and organic solvents to be mixed with the binder resin for firing.

The mass ratio of the component (A-4) in the monomer mixture (A) is 0 to 39.8 mass%, preferably 30 mass% or less, based on 100 mass% of the monomer mixture (A). Particularly 30% by mass or less, whereby the binder resin for firing can be efficiently produced. (A-4) is more preferably 20 mass% or less.

≪ Monomer mixture (1) >

The monomer mixture (1) comprises the components (a-1) and (a-2).

The component (a-1) is an alkyl (meth) acrylate and is the same as the aforementioned component (A-1). The mass ratio of the component (a-1) is 35 to 99.7 mass% based on 100 mass% of the monomer mixture (1). (a-1) is from 35 to 99.7 mass%, excellent firing can be imparted to the firing binder resin to be obtained and can be suitably used as a firing agent. The lower limit of the proportion of the component (a-1) is preferably 50% by mass or more, and more preferably 70% by mass or more.

The component (a-2) is a compound having two or more radically polymerizable unsaturated double bonds and is the same as the aforementioned component (A-2). The mass ratio of the component (a-2) is 0.3 to 5% by mass based on 100% by mass of the monomer mixture (1). and the content of the component (a-2) is from 0.3 to 5% by mass, the viscosity of the paste composition containing the obtained firing binder resin can be improved to improve the printing property and can be suitably used as a firing agent. The lower limit of the proportion of the component (a-2) is preferably 0.5% by mass or more. When the proportion of the component (a-2) is 0.5% by mass or more, the balance between the viscosity increasing effect and the thermal decomposition property is improved, and excellent printability can be given in screen printing. On the other hand, the upper limit of the ratio of the component (a-2) is preferably 3% by mass or less in view of solubility in an organic solvent.

The monomer mixture (1) may contain the component (a-3). The component (a-3) is a water-soluble unsaturated monomer and is the same as the aforementioned component (A-3). The mass ratio of the component (a-3) is 0 to 40% by mass based on 100% by mass of the monomer mixture (1). The upper limit value of the component (a-3) is preferably 30% by mass or less. This is because if it is 30 mass% or less, the firing property of the firing binder resin can be improved.

The monomer mixture (1) may contain the component (a-4) in addition to the components (a-1), (a-2) and (a-3) described above. The component (a-4) is the same as the component (A-4) described above. The mass ratio of the component (a-4) is 0 to 64.7 mass%, preferably 40 mass% or less, based on 100 mass% of the monomer mixture (1). This is because when it is 40 mass% or less, the binder resin for firing can be efficiently produced. (a-4) is more preferably 30 mass% or less.

≪ Monomer mixture (2) >

The monomer mixture (2) includes components (b-1) and (b-3).

The component (b-1) is an alkyl (meth) acrylate and is the same as the aforementioned component (A-1). (meth) acrylate, butyl (meth) acrylate, 2-ethyl (meth) acrylate, and the like. (Meth) acrylates such as hexyl (meth) acrylate and cyclohexyl (meth) acrylate. The alkyl (meth) acrylate having an alkyl group having 2 to 8 carbon atoms in the alkyl group has good solubility in an organic solvent and can be suitably used for a binder resin for firing. The component (b-1) may be the same as or different from the component (a-1). The component (b-1) may be used alone or in combination of two or more.

The mass ratio of the component (b-1) in the monomer mixture (2) is 35 to 99.9 mass% based on 100 mass% of the monomer mixture (2). and the proportion of the component (b-1) is from 35 to 99.9 mass%, the resulting firing binder resin is swollen in an organic solvent, and good printability can be exhibited. The lower limit of the proportion of the component (b-1) is preferably 50% by mass or more, and more preferably 70% by mass or more.

The monomer mixture (2) may contain the component (b-2). The component (b-2) is a compound having two or more radically polymerizable unsaturated double bonds and is the same as the aforementioned component (A-2). The component (b-2) may be the same as or different from the component (a-2). The mass ratio of the component (b-2) is 0 to 1% by mass based on 100% by mass of the monomer mixture (2). When the content is 1% by mass or less, the degree of swelling of the resultant firing binder resin in an organic solvent increases, and printing properties tend to be developed. The mass ratio of the component (b-2) in the monomer mixture (2) is preferably 0.5% by mass or less.

The component (b-3) is a water-soluble unsaturated monomer and is the same as the aforementioned component (A-3). The component (b-3) may be the same as or different from the component (a-3). The component (b-3) may be used alone or in combination of two or more.

The mass ratio of the component (b-3) in the monomer mixture (2) is 0.1 to 30 mass% based on 100 mass% of the monomer mixture (2). When the ratio of the component (b-3) is 0.1% by mass or more, the viscosity of the paste composition containing the obtained firing binder resin can be improved to improve the printing property and provide excellent leveling properties. Further, when the paste composition is used, the dispersion stability of the inorganic powder can be improved. The reason why the ratio of the component (b-3) is 30% by mass or less is to improve the firing property of the firing binder resin.

The monomer mixture 2 may contain the component (b-4) other than the components (b-1), (b-2) and (b-3) The component (b-4) is the same as the component (A-4) described above. The component (b-4) may be the same as or different from the component (a-4). The mass ratio of the component (b-4) is 0 to 64.9 mass%, preferably 30 mass% or less, based on 100 mass% of the monomer mixture (2). When the content is 30% by mass or less, the binder resin for firing can be efficiently produced.

The production method of the firing binder resin of the present invention can be produced by radical polymerization of the monomer mixture (2) in the presence of a polymer obtained by radical polymerization of the monomer mixture (1).

The mass ratio of the monomer mixture (1) is preferably 20 to 80% by mass based on 100% by mass of the total monomer mixture. When the proportion of the monomer mixture (1) is 20 to 80% by mass, tic baking of the paste composition is exhibited, and printability is improved.

On the other hand, the mass ratio of the monomer mixture (2) is preferably 20 to 80% by mass based on 100% by mass of the total monomer mixture. When the proportion of the monomer mixture (2) is 20 to 80% by mass, the viscosity of the paste composition becomes appropriate, and slack can be prevented.

On the other hand, in the present invention, in the production of the binder resin for firing, the step of radically polymerizing the monomer mixture (0) other than the monomer mixture (1) or (2) May be carried out before the first polymerization step and / or after the second polymerization step in which the monomer mixture (2) is subjected to radical polymerization, or between these steps. On the other hand, when the other monomer mixture (0) is subjected to radical polymerization before the radical polymerization of the monomer mixture (1), the polymer of the other monomer mixture (0) serves as the seed particle.

The other monomer mixture (0) includes one kind or two or more kinds of monomers capable of being radically polymerized, and the kind thereof is not particularly limited. However, depending on the polymerization timing of the other monomer mixture (0) It is preferable that at least one of the components (a-4) and (b-1) to (b-4) is included. The other monomer mixture (0) may be the same composition as the monomer mixture (1) or (2) or may be a different composition.

The mass ratio of the other monomer mixture (0) is preferably less than 50% by mass based on 100% by mass of the total monomer mixture. This is because, when the amount is less than 50 mass%, the control of the particle diameter of the resulting firing binder resin can be facilitated. The upper limit of the ratio of the other monomer mixture (0) is more preferably less than 30% by mass. In particular, in the case of polymerizing the monomer mixture (0) different only before the monomer mixture (1), the proportion of the other monomer mixture (0) is preferably less than 20% by mass.

As the polymerization method for radical polymerization of each monomer mixture, known methods such as suspension polymerization method, emulsion polymerization method and solution polymerization method can be mentioned. Among them, among the above methods, the particle diameter of the obtained firing binder resin The emulsion polymerization method is preferable.

Specifically, in the emulsion polymerization method, a monomer mixture (1), an emulsifying agent and a polymerization initiator are added to water and heated to polymerize. Thereafter, the monomer mixture (2) is added to the reaction system and polymerized.

Examples of the emulsifier include anionic emulsifiers (sodium dodecylbenzenesulfonate, sodium laurylsulfonate, sodium laurylsulfate and the like), anionic emulsifiers including polyoxyethylene groups, nonionic emulsifiers (polyoxyethylene nonylphenyl ether, Polyoxyethylene lauryl ether, etc.), a reactive emulsifier having a vinyl polymerizable double bond in the molecule, and the like.

Examples of the polymerization initiator include peroxides such as benzoyl peroxide, cumene hydroperoxide and hydrogen peroxide; Azo compounds such as azobisisobutyronitrile; Persulfate compounds such as ammonium persulfate and potassium persulfate; A peroxomonosulfuric acid compound, a perchloric acid compound, a perboric acid compound, or a redox type initiator comprising a combination of a peroxide and a reducing sulfoxide compound.

In the emulsion polymerization, as a chain transfer agent, mercaptans such as n-dodecylmercaptan, tert-dodecylmercaptan, n-octylmercaptan, n-tetradecylmercaptan, n-hexylmercaptan and the like may be used.

When the emulsion polymerization is carried out, it is preferable to use seed polymerization in which a small amount of other monomer mixture (0) is collectively polymerized to prepare seed particles, and thereafter dropwise polymerization of the monomer mixture is carried out. This is because, by using seed polymerization, the particle diameter of the obtained firing binder resin can be more easily controlled. When the seed particles are produced, the mass ratio of the other monomer mixture (0) is preferably 1 to 10% by mass based on 100% by mass of the total monomer mixture.

On the other hand, when forming the seed particles, a part of the monomer mixture 1 may be used as the other monomer mixture (0).

The smaller the particle diameter of the resulting firing binder resin, the better the solubility in an organic solvent. Therefore, the volume average particle diameter of the firing binder resin is preferably 100 占 퐉 or less, more preferably 50 占 퐉 or less. More preferably not more than 5 mu m. When the volume average particle diameter of the firing binder resin is 100 m or less, the solubility of the firing binder resin in an organic solvent can be sufficiently improved.

Here, the volume average particle diameter is a value measured using a light scattering photometer. On the other hand, the particle diameter in the present invention refers to the primary particle diameter at the time when it is produced by radical polymerization and is different from the secondary particle diameter which is the particle diameter when granulation or the like is performed after the radical polymerization.

As a result of the investigation conducted by the present inventors, it has been found that a paste composition having both leveling property and printability in screen printing can be easily obtained by using the firing binder resin obtained by the present invention. This is because, as described above, by producing the binder resin for firing by radical polymerization of the monomer mixture (2) in the presence of the polymer of the monomer mixture (1), the tie plasticity due to the structural viscosity is manifested and the fluidity in the paste is improved .

The firing binder resin obtained by the above production method is considered to have a core cell structure in which a polymer obtained by radical polymerization of the monomer mixture (1) is used as a core and a polymer obtained by radical polymerization of the monomer mixture (2) is used as a shell , It is presumed that this structure contributes to tic plasticity and fluidity.

In the firing binder resin of the present invention, it is preferable that a 15 mass% solution of the resin obtained by dissolving in terpineol satisfies the following conditions.

When? ₁ /? ₁₀ is less than 2.5

η ₁ / η ₅₀₀₀ is 5 or more

Here, η _1, η ₁₀ and η ₅₀₀₀ is a viscoelasticity measuring apparatus in the viscosity of the (Anton Parr Co., "Physca MCR300") resin was measured under the conditions of a cone plate 0.5 ° / 25mm, measured temperature 23 ℃ using the solution, η ₁ is the viscosity at shear rate 1 (1 / s), η ₁₀ is the viscosity at shear rate 10 (1 / s), and η ₅₀₀₀ is viscosity at shear rate 5000 (1 / s). On the other hand, terpineol used in the viscosity measurement is a mixture of? -Terpineol,? -Terpineol and? -Terpineol, manufactured by The Nippon Koryo Yakuhin Kaisha, Ltd. Refers to "terpineol (product name)"

(Paste composition)

The paste composition of the present invention includes the firing binder resin, inorganic powder and organic solvent.

In addition, the paste composition may contain a plasticizer, a dispersing aid, a defoaming agent and the like, if necessary.

The inorganic powder is not particularly limited as long as it can be dispersed in the firing binder resin.

Specific examples of the inorganic powder include oxides such as alumina, zirconia, titanium oxide and barium titanate, nitrides such as alumina nitride, silicon nitride, boron nitride and the like, metals such as copper, silver and nickel, Powder, various phosphors, and the like.

The preferable mass ratio of the firing binder resin to the inorganic powder varies depending on the specific gravity of the inorganic powder. For example, the solid content of the firing binder resin is preferably 3 to 30 parts by mass based on 100 parts by mass of the inorganic powder. When the solid content of the firing binder resin is 3 parts by mass or more, the inorganic powder can be easily formed, and if it is 30 parts by mass or less, a desired molded article or pattern can be obtained after firing.

As the organic solvent, those capable of dissolving the binder resin for firing are used.

The organic solvent preferably has a boiling point of 100 캜 or higher, more preferably 120 캜 or higher. When the boiling point is 100 占 폚 or higher, evaporation of the organic solvent becomes difficult, so that the workability at the time of printing or coating of the obtained paste composition is good. In the present invention, the " boiling point " is the boiling point at 1 atm (1013 hPa).

Examples of the organic solvent having a boiling point of 100 占 폚 or higher include?,?,? -Terpineol, propylene glycol monomethyl ether, ethyl-3-ethoxypropionate, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, Ethylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2,2,4-trimethyl-1,3- 1-octanol, 1-octanol, 2-ethyl-1-hexanol, 1-decanol, 1-undecanol , 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,5-pentanediol, toluene, dimethylsulfoxide, dimethylformamide Imide, dimethylacetamide, N-methylpyrrolidone, and the like. The organic solvent may be used alone, or two or more kinds may be used in combination.

Of the above organic solvents, α, β, γ-terpineol and propylene glycol monomethyl ether are preferable because of their excellent solubility.

In order to increase the viscosity of the paste composition so as to enable screen printing or dip coating, it is preferable that 50% by mass or more of?,?,? -Terpineol is contained in the organic solvent, more preferably 70% Do.

The content of the organic solvent in the paste composition is preferably 5 to 70% by mass based on 100% by mass of the paste composition. When the content of the organic solvent is 5% by mass or more, fluidity can be imparted to the paste. When the content is 70% by mass or less, high printing properties can be exhibited.

Since the above-mentioned paste composition contains the firing binder resin of the present invention, the leveling property and the printability in screen printing are excellent.

Since this paste composition is excellent in printing property in screen printing, it is preferable to apply screen printing when forming a pattern on a substrate, but a method other than screen printing may be applied. When the viscosity of the paste composition is high, the dip coating method and the dispense coating method can be applied. When the viscosity is low, a doctor blade coating method or casting coating method can be applied.

Examples of the substrate on which the paste composition is printed or applied include ceramics substrates, capacitors, and the like.

(Inorganic sintered body)

The inorganic sintered body of the present invention is an inorganic sintered body obtained by firing the paste composition. Examples of the firing method include a method in which the paste composition is placed under a high-temperature atmosphere in a printed or coated substrate, but the present invention is not limited thereto. In the firing step, the organic material including the firing binder resin contained in the paste composition is decomposed and removed, the inorganic powder is melted and sintered, and an inorganic sintered body is obtained. The firing temperature is usually 200 to 1500 占 폚, preferably 300 to 1000 占 폚, though it can be suitably determined depending on the melting temperature of the substrate, the inorganic powder, the kind of the organic material contained in the paste composition and the like.

Example

Hereinafter, the present invention will be described with reference to examples and comparative examples. In the following examples, "part" means "part by mass" and "%" means "% by mass".

The measurement and evaluation method in the following examples and the method of producing the binder resin for firing are as follows.

<Measurement and evaluation method>

(Measurement of Volume Average Particle Diameter)

The volume average particle diameter of the particles of the firing binder resin was measured using a light scattering photometer ("FPAR-1000 type", manufactured by Otsuka Electronics Co., Ltd.).

(Evaluation of leveling property)

The viscosity of the firing binder resin solution was measured using a viscoelasticity measuring device (Physca MCR300, manufactured by Anton PARAS) under conditions of a cone plate of 0.5 deg. / 25 mm and a measurement temperature of 23 deg. The value of? ₁ /? ₁₀ when the viscosity at shear rate 1 (1 / s) is? ₁ and the viscosity at shear rate 10 (1 / s) is? ₁₀ is obtained. Then, the leveling property was evaluated by the following evaluation criteria. On the other hand, the smaller the value of? ₁ /? ₁₀ , the better the leveling property.

⊚: η ₁ / η ₁₀ is less than 2.0.

?:? ₁ /? ₁₀ is 2.0 or more and less than 2.5.

×: η ₁ / η ₁₀ is 2.5 or more.

(Evaluation of printability)

And by measuring the viscosity as in the leveling evaluation of a shear rate 1 (1 / s) the viscosity when the η _1, a shear rate of 5000 (1 / s) of η ₁ / η, when the viscosity η ₅₀₀₀ when the ₅₀₀₀ was obtained. The printability was evaluated by the following evaluation criteria. On the other hand, the larger the value of? ₁ /? ₅₀₀₀ , the better the printing property.

?:? ₁ /? ₅₀₀₀ is 10 or more.

○: η ₁ / η ₅₀₀₀ is 5 or more and less than 10.

×: η ₁ / η ₅₀₀₀ is less than 5.

(Evaluation of Heat Loss Rate)

5 mg of a measurement sample was heated in air (starting temperature) from 30 DEG C to 500 DEG C at a rate of 15 DEG C / min using a differential thermal balance TG-DTA (trade name: Thermo plus EVO, manufactured by Rigaku Corporation) (%) At 450 deg. C was obtained according to the following formula.

Heat Dissipation Rate (%) = (Sampling Mass (mg) - Mass of Residue (mg)) / Sampling Mass (mg)

&Lt; Method for producing binder resin for firing >

(Production Examples 1 to 9)

To the polymerization apparatus capable of heating and cooling, 100 parts of water, sodium dialkyl sulfosuccinate sodium ("Parex OTP", manufactured by Kao Corporation) shown in Table 1 as an emulsifier, and potassium persulfate 0.05 part were added. Further, 4 parts of isobutyl methacrylate was added to the polymerization apparatus, and the mixture was heated at 80 DEG C for 0.5 hour while stirring at 150 rpm in a nitrogen atmosphere, to obtain an emulsion containing seed particles.

To the emulsion containing the seed particles, 25 parts of deionized water, 1 part of sodium dialkyl sulfosuccinate (manufactured by Kao Corporation, "Parex OTP") as an emulsifier, and 1 part of a monomer mixture of the mass ratios (1) 48 parts were emulsified and dropped over 2 hours, followed by heating at 80 占 폚 for 0.5 hour to polymerize.

Subsequently, 25 parts of deionized water, 1 part of sodium dialkyl sulfosuccinate (manufactured by Kao Corporation, "Parex OTP") as an emulsifier and 48 parts of the monomer mixture (2) in the mass ratio shown in Table 1 were emulsified to obtain a reaction solution For 2 hours, and then kept at 80 캜 for 1 hour to obtain an emulsion of a binder resin for firing.

The resulting emulsion of the binder resin for firing was subjected to heat treatment at a chamber inlet temperature of 150 캜 and a chamber outlet temperature of 55 캜 using a spray drying apparatus ("L-8 type", manufactured by Ohkawara Kakohki Co., Ltd.) And spray-dried under conditions of an atomizer rotation speed of 20000 rpm to obtain particles A1 to A9 of a binder resin for firing.

Table 1 shows the measurement results of the volume average particle diameter of the resulting firing binder resin.

(Preparation Example 10)

In the same manner as in Examples 1 to 9, an emulsion containing seed particles was prepared.

To 15 parts of deionized water, 0.5 part of sodium dialkyl sulfosuccinate (manufactured by Kao Corporation, "Parex OTP") as an emulsifier, and 30 parts by mass of a monomer mixture (1) shown in Table 1 were added to the emulsion containing the seed particles The mixture was emulsified and dripped over 1.5 hours, and then polymerized by heating at 80 DEG C for 0.5 hour.

Subsequently, 35 parts of deionized water, 1.5 parts of sodium dialkyl sulfosuccinate (manufactured by Kao Corporation, Parex OTP) as an emulsifier, and 66 parts of the monomer mixture (2) shown in Table 1 were emulsified to obtain a reaction solution Over 2.5 hours, and then kept at 80 DEG C for 1 hour to obtain an emulsion of a binder resin for firing.

The emulsion of the obtained firing binder resin was spray-dried in the same manner as in Examples 1 to 9 to obtain a firing binder resin (A10).

Table 1 shows the measurement results of the volume average particle diameter of the resulting firing binder resin.

(Preparation Example 11)

100 parts of water and 0.05 parts of potassium persulfate as a polymerization initiator were added to a polymerization apparatus capable of heating and cooling. And the mixture was heated to 80 DEG C while stirring at 150 rpm in a nitrogen atmosphere.

To this, 35 parts of deionized water, 1.5 parts of sodium dialkyl sulfosuccinate (manufactured by Kao Corporation, "Parex OTP") as an emulsifier, and 75 parts of the monomer mixture (1) in the mass ratio shown in Table 1 were emulsified, , And the mixture was polymerized by heating at 80 DEG C for 0.5 hour.

Subsequently, 15 parts of deionized water, 0.5 part of sodium dialkyl sulfosuccinate (manufactured by Kao Corp., "Parex OTP") as an emulsifier and 25 parts of the monomer mixture (2) shown in Table 1 were emulsified to obtain a reaction solution Dropwise over 1.5 hours, and then maintained at 80 DEG C for 1 hour to obtain an emulsion of a binder resin for firing.

The emulsion of the resulting firing binder resin was spray-dried in the same manner as in Examples 1 to 9 to obtain a firing binder resin (A11).

Table 1 shows the measurement results of the volume average particle diameter of the resulting firing binder resin.

(Comparative Production Example 1)

A solution obtained by dissolving 7.5 parts of polyvinyl alcohol in 1000 parts of pure water was charged into a 2 L (liter) four-necked flask capable of being heated and cooled. To this were added 225 parts of isobutyl methacrylate, 269.75 parts of 2-ethylhexyl methacrylate, 5 parts of methacrylic acid, 5 parts of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.). ), And 2.5 parts of lauryl peroxide were further added and stirred vigorously at 300 rpm to obtain a suspension. The temperature was raised to 80 ° C, and the mixture was stirred for 5 hours And the polymerization was terminated.

The resulting suspension was washed, dehydrated and dried to obtain a firing binder resin (A12).

Table 2 shows the mass ratio of each monomer component when the monomer mixture (1) is 100 mass%, and the measurement results of the average particle diameter of the obtained binder resin for firing.

(Comparative Production Example 2)

100 parts of water, 0.05 parts of sodium dialkyl sulfosuccinate (manufactured by Kao Corporation, "Parex OTP") in an amount shown in Table 2 as an emulsifier and potassium persulfate as a polymerization initiator were added to the polymerization apparatus capable of heating and cooling . Further, 2 parts of methyl methacrylate and 2 parts of isobutyl methacrylate were added to the polymerization apparatus, and the mixture was heated at 80 ° C for 0.5 hour while stirring at 150 rpm in a nitrogen atmosphere to obtain an emulsion containing the seed particles .

To the emulsion containing the seed particles, 50 parts of deionized water, 2 parts of sodium dialkyl sulfosuccinate (manufactured by Kao Corporation, "Parex OTP") as an emulsifier, and a monomer mixture of the mass ratios (1) 96 parts were emulsified and dripped over 4 hours, and then heated at 80 占 폚 for 1 hour to obtain an emulsion of a binder resin for firing.

The resulting emulsion of the binder resin for firing was sprayed at a chamber inlet temperature of 150 占 폚, a chamber outlet temperature of 55 占 폚, and an atomizer rotation speed of 20,000 rpm using a spray dryer ("L-8 type", manufactured by Okawa Ragokoki Co., And dried to obtain a firing binder resin (A13).

Table 2 shows the measurement results of the volume average particle diameter of the obtained firing binder resin.

[Examples 1 to 11, Comparative Examples 1 and 2]

150 parts of the firing binder resins (A1 to A13) of the kind shown in Tables 1 and 2 were placed in a 2-liter three-necked flask. Thereto were added terpineol (? -,? -,? (Trade name, manufactured by Nippon Goryo Yakuhin Co., Ltd.)) was added thereto. Thereafter, the temperature was raised to 80 캜 and dissolved for 3 hours to obtain a binder resin solution for firing.

The resulting firing binder resin solution was evaluated for leveling property and printing property. The results are shown in Tables 1 and 2.

[Examples 12 and 13]

The heat-reduction rate of the firing binder resins A1 and A4 was evaluated. The results are shown in Table 3.

[Reference Example]

Ethyl cellulose (manufactured by Nisshin Kasei Co., Ltd., trade name: STD100) was evaluated. The results are shown in Table 3.

The symbols in Tables 1 and 2 are as follows. On the other hand, the amounts of the respective monomers in the monomer mixtures (0) to (2) shown in Tables 1 and 2 are the mass ratios when the monomer mixtures (0) to (2) are each 100 mass%. The seed (0) in Tables 1 and 2 has the same meaning as the other monomer mixture (0).

IBMA: isobutyl methacrylate

NBMA: n-butyl methacrylate

MMA: methyl methacrylate

EHMA: 2-ethylhexyl methacrylate

· EDMA: ethylene glycol dimethacrylate

DPHA: dipentaerythritol hexaacrylate

HEMA: 2-hydroxyethyl methacrylate

· MAA: methacrylic acid

AA: Acrylic acid

As is clear from Tables 1 and 2, all of the firing binder resin solutions obtained in the Examples had good leveling properties and printability.

Further, as is evident from Table 3, the firing binder resins A1 and A4 were superior in thermal decomposition to ethyl cellulose.

The firing binder resin of the present invention is useful as a component of a paste composition having both leveling property and printability in screen printing. Further, according to the production method of the present invention, such a binder resin for firing can be easily obtained, which is useful.

Claims (6)

60 to 99.8 mass% of alkyl (meth) acrylate (A-1)
0.1 to 5% by mass of a compound (A-2) having at least two radically polymerizable unsaturated double bonds,
0.1 to 30% by mass of a water-soluble unsaturated monomer (A-3) (provided that it is a monomer other than the compound (A-2) having two or more radically polymerizable unsaturated double bonds)
0 to 39.8 mass% of other copolymerizable monomer (A-4)
And 15% by mass of the resin obtained by dissolving the resin in terpineol, and a 15% by mass solution of the resin obtained by dissolving the resin in terpineol, is obtained by copolymerization of a resin obtained by copolymerizing a monomer mixture (A) A binder material for firing satisfying the following conditions.
When? ₁ /? ₁₀ is less than 2.5
η ₁ / η ₅₀₀₀ is 5 or more
Where? ₁ ,? ₁₀ and? ₅₀₀₀ are the viscosities of the resin solutions measured under conditions of a cone plate of 0.5 deg. / 25 mm and a measurement temperature of 23 deg. C using a viscoelasticity measuring apparatus (Anton Pacca, "Physca MCR300" η ₁ is the viscosity at shear rate 1 (1 / s), η ₁₀ is the viscosity at shear rate 10 (1 / s), and η ₅₀₀₀ is viscosity at shear rate 5000 (1 / s) 35 to 99.7 mass% of alkyl (meth) acrylate (a-1)
0.3 to 5% by mass of a compound (a-2) having two or more radically polymerizable unsaturated double bonds,
0 to 40% by mass of a water-soluble unsaturated monomer (a-3) (provided that it is a monomer other than the compound (a-2) having two or more radically polymerizable unsaturated double bonds)
Other monomer (a-4) 0 to 64.7 mass%
In the presence of a first polymer obtained by radical polymerization of a monomer mixture (1)
35 to 99.9% by mass of alkyl (meth) acrylate (b-1)
0 to 1% by mass of a compound (b-2) having at least two radically polymerizable unsaturated double bonds,
0.1 to 30% by mass of a water-soluble unsaturated monomer (b-3) (provided that it is a monomer other than the compound (b-2) having two or more radically polymerizable unsaturated double bonds)
Other monomer (b-4) 0-64.9 mass%
, And a second polymer obtained by radical polymerization of a monomer mixture (2) containing a terpineol, and an organic solvent containing terpineol. The method according to claim 1,
Wherein the resin is a particle having a volume average particle diameter of 100 占 퐉 or less. 3. The method of claim 2,
Wherein the resin is a particle having a volume average particle diameter of 100 占 퐉 or less. A paste composition comprising the binder for firing according to any one of claims 1 to 4 and an inorganic powder. An inorganic sintered body obtained by firing the paste composition according to claim 5.