JP2007169446A - Acrylic resin composition and paste composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acrylic resin composition which is excellent in thixotropy and by which not only a screen printing can be easily performed, but also a paste composition which can be baked at a low temperature can be obtained; and a paste composition comprising the acrylic resin composition. <P>SOLUTION: This acrylic resin composition is represented by formula (1): R<SB>1</SB>COOR<SB>2</SB>OH (wherein, R<SB>1</SB>is a 1-6C straight or branched organic group and R<SB>2</SB>is a 1-10C straight or branched organic group) and comprises: a solvent having in the molecule thereof one hydroxyl group and one ester bond; a (meth)acrylic resin obtained by polymerizing a polymerizable monomer in the solvent; and an organic compound having three or more hydroxyl groups. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an acrylic resin composition excellent in thixotropy, and more specifically, an acrylic resin composition excellent in screen printability and capable of being fired at a low temperature, and a paste composition containing the acrylic resin composition Related to things.

  In recent years, paste compositions in which inorganic fine particles such as conductive powder and ceramic powder are dispersed in a resin binder have been used to obtain sintered bodies having various shapes.

  The sintered body made of the paste composition is fired after making the paste composition into a predetermined shape by, for example, a screen printing method, a coating method using a doctor blade, a casting method for processing into a sheet shape, or the like. Can be obtained. Among these, the screen printing method is particularly suitable for mass production.

  The paste composition used for screen printing is required to have a sufficiently low viscosity and easy coating when applied. On the other hand, when allowed to stand and dry after coating, it is required that the viscosity is sufficiently high and the paste composition does not naturally cast. Therefore, in order to perform screen printing satisfactorily, the paste composition preferably has thixotropic properties, that is, thixotropic properties. The thixotropy refers to, for example, when the viscosity of the paste composition is evaluated with a rotational viscometer, the viscosity decreases as the rotational speed increases (displacement with high strain rate), and the rotational speed decreases (strain speed). Is a property of increasing viscosity.

At present, pastes using ethyl cellulose as a binder resin are used for screen printing, but paste compositions using ethyl cellulose resins have high thixotropy and excellent screen printability, but the heat of ethyl cellulose resins. Since the decomposition temperature is high, the inorganic fine particles contained in the paste composition may be thermally deteriorated during the thermal decomposition.
Therefore, various studies for imparting screen printability using an acrylic resin which is a low-temperature decomposable resin have been conducted.

In the following Patent Document 1, at least (A) 100 parts by weight of a polymer-containing solution having a solution viscosity of 100 to 4000 centipoise, (B) 10 to 1000 parts by weight of a phosphor, and (C) a thixotropic agent 0. A phosphor paste composition containing 1 to 10 parts by weight is disclosed. The phosphor paste composition described in Patent Document 1 contains a relatively low viscosity polymer solution (A) and a thixotropy imparting agent (C), so that the stringiness during screen printing is low and the screen printability is low. It is said that it is excellent.
JP 2000-144124 A

  Although the paste composition described in Patent Document 1 has excellent screen printability, stringiness, and thixotropy, the amount of acrylic resin in the paste composition is large, so it needs to be heated for a long time to be completely decomposed. In order to enable firing at a low temperature, it was necessary to reduce the amount of acrylic resin in the paste composition. On the other hand, when the amount of the acrylic resin in the paste composition is reduced, the thixotropy may be lowered. That is, there has been a strong demand for a paste composition having a high thixotropy while reducing the amount of acrylic resin in the paste composition to enable firing at a low temperature.

  An object of the present invention is to provide an acrylic resin composition that is excellent in thixotropy, can be easily screen-printed, and can be baked at a low temperature in view of the current state of the prior art described above. And a paste composition containing the acrylic resin composition.

The acrylic resin composition according to the present invention is obtained by polymerizing a polymerizable monomer in a solvent represented by the following formula (1) and having one hydroxyl group and one ester bond in the molecule. The obtained (meth) acrylic resin and an organic compound having three or more hydroxyl groups are contained.
R ₁ COOR ₂ OH (1)
In the above formula (1), R ₁ is a linear or branched organic group having 1 to 6 carbon atoms, and R ₂ is a linear or branched organic group having 1 to 10 carbon atoms. It is a group.

  In a specific aspect of the acrylic resin composition according to the present invention, the (meth) acrylic resin is composed mainly of (meth) acrylate having 10 or less carbon atoms.

  In another specific aspect of the acrylic resin composition according to the present invention, the number average molecular weight of the (meth) acrylic resin is in the range of 7000 to 120,000.

  The paste composition according to the present invention comprises at least one powdery material selected from the group consisting of an acrylic resin composition constituted according to the present invention and a metal, glass, carbon black, metal complex, silica-based compound and ceramics. It is characterized by including.

  In another specific aspect of the paste composition according to the present invention, the solvent is contained in a proportion of 40 to 60% by weight in 100% by weight of the paste composition.

In another specific aspect of the paste composition according to the present invention, when measuring the viscosity at 23 ° C. using a B-type viscometer, and the viscosity eta _{5 rpm} in the rotational speed 5 rpm, the viscosity eta _30rpm in rotational speed 30rpm The ratio η _{5 rpm} / η _{30 rpm} is 1.5 or more.

  The acrylic resin composition according to the present invention is represented by the formula (1) described above, and has a solvent having one hydroxyl group and one ester bond in the molecule, a (meth) acrylic resin, and three or more hydroxyl groups. Containing organic compounds. In the present invention, a (meth) acrylic resin was obtained by polymerizing a polymerizable monomer in a solvent represented by the above formula (1) and having one hydroxyl group and one ester bond in the molecule ( Since it is a (meth) acrylic resin, for example, when compared with terpineol, butyl carbitol acetate, butyl carbitol, etc., which are suitably used as an organic solvent, the viscosity increases even when the content of (meth) acrylic resin is small, Sufficient thixotropy can be expressed. In other words, in the acrylic resin composition according to the present invention, since the content of the (meth) acrylic resin can be reduced, the decomposition can be completed in a shorter time. Further, since the (meth) acrylic resin itself has adhesiveness, it is possible to improve screen printing defects caused by adhesiveness by reducing the amount of resin.

  Therefore, in the paste composition in which the powdery material is dispersed in the acrylic resin composition according to the present invention, the content of the (meth) acrylic resin is reduced, and the screen has sufficient thixotropy. Printing can be performed easily. Further, for example, (meth) acrylic resin is thermally decomposed at a lower temperature than cellulose resin and the like, and therefore, when obtaining a sintered body made of a paste composition containing an acrylic resin composition, it can be fired at a much lower temperature. it can.

  When the (meth) acrylic resin is composed mainly of (meth) acrylate having 10 or less carbon atoms, the content of the acrylic resin can be further reduced and the viscosity can be sufficiently increased. .

  If the number average molecular weight of the (meth) acrylic resin is less than 7000, the amount of the resin may not be reduced, and if it exceeds 120,000, the adhesiveness and stringiness of the paste composition may be deteriorated. The number average molecular weight of the resin is preferably in the range of 7000 to 120,000.

  In the paste composition according to the present invention, at least one powdery material selected from the group consisting of an acrylic resin composition constituted according to the present invention, and a metal, glass, carbon black, metal complex, silica-based compound, and ceramics. , A powdery fired body can be obtained at a lower temperature.

  When the solvent is contained in a proportion of 40 to 60% by weight in 100% by weight of the paste composition, the (meth) acrylic resin fraction can be lowered and the viscosity characteristics necessary for screen printing can be ensured.

When the viscosity η ₅ rpm at a rotational speed of 5 _rpm and the ratio η _{5 rpm} / η ₃₀ rpm at a rotational speed of 30 _rpm is 1.5 or more when the viscosity at 23 ° C. is measured using a B-type viscometer The paste composition has thixotropy and can be said to be suitable for screen printing.

  Details of the present invention will be described below.

The acrylic resin composition according to the present invention is polymerized with a solvent (A) represented by the following formula (1) and having one hydroxyl group and one ester bond in the molecule, and the polymerizable monomer in the solvent. The (meth) acrylic resin obtained by this and the organic compound which has 3 or more of hydroxyl groups are contained.
R ₁ COOR ₂ OH (1)
The solvent (A) is not particularly limited as long as it is represented by the above formula (1) and has one hydroxyl group and one ester bond in the molecule. In the above formula (1), R ₁ is a linear or branched organic group having 1 to 6 carbon atoms, and R ₂ is a linear or branched structure having 1 to 10 carbon atoms. Is an organic group.

  When a paste composition is formed using an acrylic resin composition containing the solvent (A), a (meth) acrylic resin, and an organic compound having three or more hydroxyl groups, a large amount of (meth) acrylic resin is blended. Without it, the viscosity can be increased. Since the molecular structure of the solvent (A) is similar to the repeating structure of the (meth) acrylic resin, the interaction between the solvent and the (meth) acrylic resin is large, and the viscosity of the paste composition is increased.

Specific examples of the linear or branched organic group R ₁ having 1 to 6 carbon atoms are not particularly limited, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and a butyl group. And those in which a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or the like is bonded to any carbon atom of these groups.

Specific examples of the linear or branched organic group R ₂ having 1 to 10 carbon atoms are not particularly limited. For example, methylene group, ethylene group, n-propylene group, isopropylene group, n-butylene. A group, an n-pentylene group, an n-hexylene group, an n-heptylene group, an n-octylene group, an n-nanone group, etc., and a carbon atom of any one of these groups, a methyl group, an ethyl group, an n-propyl group, The thing which the isopropyl group etc. couple | bonded is mentioned.

As the solvent (A), since the viscosity is further increased, a solvent in which R ₁ has 2 or 3 carbon atoms and R ₂ has 3 to 8 carbon atoms is preferable. Used.

Specific examples of the linear or branched organic group R ₁ having 2 or 3 carbon atoms include an ethyl group, an n-propyl group, and an isopropyl group. Examples of the linear or branched organic group R ₂ having 3 to 8 carbon atoms include n-propylene group, isopropylene group, n-butylene group, n-pentylene group, n-hexylene group, and n-heptylene. A group, an n-octylene group, or the like, or a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or the like bonded to any carbon atom of these groups so that the number of carbon atoms is in the range of 3 to 8 Etc.

More preferable specific examples of the solvent (A) include 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (also known as texanol) represented by the following formula (2), or the following formula ( 1,3-propylene glycol monoisobutyrate represented by 3). When the acrylic resin composition contains 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate or 1,3-propylene glycol monoisobutyrate, the viscosity and viscosity ratio η _{5 rpm} / η _{30 rpm} (Thixotropy) is further enhanced. In order to further increase thixotropy, it is more preferable to use 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (also known as texanol).

  As the solvent (A), a solvent having a boiling point of less than 400 ° C. is preferably used in order to enable a paste composition containing an acrylic resin composition to be fired at a low temperature, more preferably a boiling point of 350 The boiling point is less than 300 ° C, more preferably less than 300 ° C. The boiling point of the solvent (A) is preferably 200 ° C. or higher so that the paste composition can be fired at a low temperature and the solvent is prevented from volatilizing during the kneading process.

  When the viscosity of the solvent (A) at 20 ° C. is measured using a B-type viscometer, it is preferably 6 mPa · s or more. When the viscosity of the solvent (A) is 6 mPa · s or more, the viscosity can be increased even when the paste composition is constituted without containing a large amount of (meth) acrylic resin.

  The (meth) acrylic resin is not particularly limited, and examples thereof include a homopolymer of a (meth) acrylate monomer, a copolymer of a (meth) acrylate monomer and a polyoxyalkylene (meth) acrylate monomer, and the like. Especially, the copolymer of a (meth) acrylate monomer and a polyoxyalkylene (meth) acrylate monomer is used suitably. Moreover, what mixed the homopolymer of the (meth) acrylate monomer and the copolymer of the (meth) acrylate monomer and the polyoxyalkylene (meth) acrylate monomer may be used.

  In the present specification, (meth) acrylate means acrylate or methacrylate.

  The (meth) acrylate monomer that is a polymerizable monomer is not particularly limited, and examples thereof include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, and tert-butyl. (Meth) acrylate, isobutyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isobornyl (meth) acrylate, n-stearyl (meth) acrylate, benzyl (meth) acrylate, and the like. Among these, it is preferable to use a (meth) acrylate monomer having 10 or less carbon atoms, and methyl (meth) acrylate that increases the glass transition temperature of the polymer is more preferably used. These (meth) acrylate monomers may be used alone or in combination of two or more.

  The polyoxyalkylene (meth) acrylate monomer that is a polymerizable monomer is not particularly limited, and examples thereof include polymethylene glycol, polyacetal, polyethylene glycol, polypropylene glycol, polytrimethylene glycol, polytetramethylene glycol, and polybutylene glycol. Examples include (meth) acrylic acid esters. Of these, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, and (meth) acrylic acid ester of polytetramethylene glycol are preferably used. Moreover, thixotropy can be improved by using together with the organic compound which has 3 or more of hydroxyl groups.

  The (meth) acrylic resin preferably has a structural unit derived from a (meth) acrylate monomer having 10 or less carbon atoms and a polyoxyalkylene (meth) acrylate monomer. The (meth) acrylic resin having this structural unit has a particularly low decomposition temperature, and the paste composition can be fired at a lower temperature. Furthermore, a copolymer composition of (meth) acrylic acid ester of polypropylene glycol and methyl (meth) acrylate is more preferably used because it decomposes at a lower temperature and easily develops thixotropy.

  It does not specifically limit as a polymerization method of the said (meth) acrylic resin, The method used for superposition | polymerization of a normal (meth) acryl monomer is mentioned. Specific examples include a free radical polymerization method, a living radial polymerization method, an iniferter polymerization method, an anionic polymerization method, and a living anion polymerization method.

  In the present invention, the (meth) acrylic resin is obtained by polymerizing the polymerizable monomer described above in the solvent (A). In this case, a paste composition containing an acrylic resin composition exhibits a sufficient viscosity even if it does not contain a large amount of (meth) acrylic resin. When the (meth) acrylic resin is obtained by polymerizing the polymerizable monomer in the solvent (A), the interaction between the solvent (A) and the (meth) acrylic resin is further increased, so the viscosity of the paste composition Is further enhanced.

  Further, in order to increase the viscosity of the acrylic resin composition and enhance the interaction with the solvent (A), the (meth) acrylic resin is mainly composed of (meth) acrylate having 10 or less carbon atoms. It is preferable.

  The number average molecular weight of the (meth) acrylic resin is preferably in the range of 7000 to 120,000. When the number average molecular weight is less than 7000, the amount of resin in the paste composition may not be reduced. When the number average molecular weight exceeds 120,000, the adhesiveness and stringiness of the paste composition are deteriorated and the screen printability is poor. Sometimes. In addition, the number average molecular weight of (meth) acrylic resin shall mean the polystyrene conversion number average molecular weight of (meth) acrylic resin measured by gel permeation chromatography (GPC). In addition, as a column at the time of measuring a polystyrene conversion number average molecular weight by GPC, a column LF-804 manufactured by SHOKO Co., Ltd. and the like can be mentioned.

  Examples of the organic compound having three or more hydroxyl groups include glycerin, diglycerin, trimethylolpropane, pentaerythritol, L-threitol, D-threitol, 2-hydroxymethyl-1,3-propanediol, 1,1, Examples include 1-trihydroxymethylethane, 1,2,4-butanetriol, 1,2,6-hexanetriol and the like. When the acrylic resin composition contains the organic compound having three or more hydroxyl groups, sufficient thixotropy can be exhibited when the paste composition is formed. It is preferable to use glycerin because it can express even better thixotropy.

  The paste resin composition according to the present invention is an at least one powder selected from the group consisting of an acrylic resin composition constituted according to the present invention, and a metal, glass, carbon black, metal complex, silica compound, and ceramics. Including things. In this case, the paste composition has the performance derived from the powdery material, and can make use of the low temperature decomposability of the (meth) acrylic resin. For example, a glass molded body can be obtained by baking a paste composition whose powder is glass.

Specifically, as the powdery material, for example, copper, silver, nickel, palladium, alumina, zirconia, titanium oxide, barium titanate, alumina nitride, silicon nitride, boron nitride, silicate glass, lead glass, CaO · Al ₂ O ₃ · SiO ₂ inorganic glass, MgO · Al ₂ O ₃ · SiO ₂ inorganic glass, LiO ₂ · Al ₂ O ₃ · SiO ₂ inorganic glass, low melting point glass, various carbon blacks, carbon Examples thereof include metal oxides such as nanotubes, titanium oxide, and zirconium oxide, and metal complexes.

  It is preferable that the said powdery material is contained in the ratio of 25 to 50 weight% in 100 weight% of paste compositions. More preferably, it is 30 to 45% by weight. When the powder is less than 25% by weight, the storage stability is deteriorated, the powder is separated and settled, and when the powder is more than 50% by weight, the powder is uniformly dispersed in the paste composition. It becomes difficult to do.

  Moreover, it is preferable that the said (meth) acrylic resin is contained in the ratio of 7-20 weight% in 100 weight% of paste compositions. More preferably, it is 10 to 15% by weight. If the (meth) acrylic resin is less than 7% by weight, the powdery product may not be uniformly dispersed in the paste composition, and if it exceeds 20% by weight, the viscosity of the paste composition is high, and the tackiness and stringing deteriorate. Therefore, the screen printability may be inferior.

  It is preferable that the said solvent (A) is contained in the ratio of 40-60 weight% in 100 weight% of paste compositions. More preferably, it is 45 to 55% by weight. If the solvent (A) is less than 40% by weight, the viscosity of the paste composition may be too high and the screen printability may be poor, and if it exceeds 65% by weight, the storage stability of the paste composition may be poor.

  The addition amount of the organic compound having 3 or more hydroxyl groups is preferably 0.1 to 20% by weight in 100% by weight of the paste composition because the thixotropy of the paste composition is effectively enhanced. If it is less than 0.1% by weight, sufficient thixotropy cannot be expressed, and if it exceeds 20% by weight, the storage stability may be inferior.

  Moreover, the paste composition may contain a surfactant, a dispersant, an organic solvent, etc. in addition to the components described above.

  The method for producing the acrylic resin composition or paste composition is not particularly limited. An acrylic resin composition or paste composition can be obtained by treating each of the above-described blending components with a conventionally known stirring method, specifically, for example, a three-roll, bead mill, planetary stirrer or the like.

Using a B-type viscometer, when the viscosity was measured at 23 ° C. of the paste composition, the viscosity eta _{5 rpm} in the rotational speed 5 rpm, the ratio eta _{5 rpm} / eta _30rpm with viscosity eta _30rpm in rotational speed 30rpm 1.5 The above is preferable. When the viscosity ratio η _{5 rpm} / η _{30 rpm} is 1.5 or more, the paste composition has high _thixotropy and can be easily screen-printed.

  Hereinafter, the present invention will be clarified by describing specific examples and comparative examples of the present invention. The present invention is not limited to the following examples.

Example 1
A 2L separable flask equipped with a stirrer, a cooler, a thermometer, and a nitrogen gas inlet has 90 parts by weight of methyl methacrylate (MMA), a hydrogen-bonding functional group, and a polyoxyalkylene side chain As a methacrylate, 10 parts by weight of polypropylene glycol monomethacrylate (Blenmer PP1000 manufactured by NOF Corporation), a chain transfer agent dodecyl mercaptan (DDM), and 2,2,4-trimethyl-1,3-pentanediol mono as an organic solvent 100 parts by weight of isobutyrate was mixed to obtain a monomer mixture.

  The obtained monomer mixture is bubbled with nitrogen gas for 20 minutes to remove dissolved oxygen, and then the temperature inside the separable flask system is replaced with nitrogen gas and stirred until the solution temperature reaches 95 ° C. did. After reaching 95 ° C., a solution obtained by diluting the polymerization initiator with ethyl acetate was added. During the polymerization, an ethyl acetate solution containing a polymerization initiator was added several times.

  Ten hours after the start of the polymerization, the polymerization was terminated by cooling to room temperature. Thus, a 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate solution of a polymer having a polyoxyalkylene side chain was obtained. When the obtained (meth) acrylic resin was analyzed by GPC, the number average molecular weight in terms of polystyrene was 30000. For measurement of polystyrene-equivalent number average molecular weight, a column LF-804 manufactured by SHOKO was used as the column.

  The 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate solution of the (meth) acrylic resin obtained as described above was added to the 2,2,4-trimethyl-1,3-pentanediol monoisobutylate. Add further butyrate, disperse using high speed disperser, and contain 50 parts by weight of 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate with respect to 14 parts by weight of (meth) acrylic resin A dispersion is obtained.

  Next, 1 part by weight of glycerin having 3 hydroxyl groups and 35 parts by weight of glass powder were further added to the dispersion and sufficiently kneaded using a three roll to obtain a glass paste composition. In addition, the acrylic resin composition which did not mix | blend only 35 weight part of glass powder was obtained similarly.

(Example 2)
As a solvent (A), instead of 100 parts by weight of 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 1,3-propylene glycol monoisobuty represented by the above formula (3) A mixed solution was obtained in the same manner as in Example 1 except that 100 parts by weight of the rate was used.

  Thereafter, a polymerization reaction was carried out in the same manner as in Example 1 to obtain a 1,3-propylene glycol monoisobutyrate solution of (meth) acrylic resin. The obtained (meth) acrylic resin was analyzed by GPC in the same manner as in Example 1. As a result, the number average molecular weight in terms of polystyrene was 30000.

  1,3-propylene glycol monoisobutyrate is further added to the 1,3-propylene glycol monoisobutyrate solution of the (meth) acrylic resin obtained as described above, and dispersed using a high-speed disperser, A dispersion containing 50 parts by weight of a 1,3-propylene glycol monoisobutyrate solution with respect to 14 parts by weight of a (meth) acrylic resin was obtained.

  Next, 1 part by weight of glycerin having 3 hydroxyl groups and 35 parts by weight of glass powder were further added to the dispersion and sufficiently kneaded using a three roll to obtain a glass paste composition. In addition, the acrylic resin composition which did not mix | blend only 35 weight part of glass powder was obtained similarly.

(Comparative Example 1)
A 2 L separable flask equipped with a stirrer, a cooler, a thermometer, and a nitrogen gas inlet was prepared. In this separable flask, 90 parts by weight of methyl methacrylate, polypropylene glycol monomethacrylate (Nippon Yushi Co., Ltd., BLEMMER PP-), which is a (meth) acrylate having a hydrogen bonding functional group and containing a polyoxyalkylene side chain. 1000) 10 parts by weight, a chain transfer agent (DDM), and 50 parts by weight of terpineol represented by the following formula (4) were mixed to obtain a mixed solution.

  Thereafter, a polymerization reaction was carried out in the same manner as in Example 1 to obtain a terpineol solution of (meth) acrylic resin. The obtained (meth) acrylic resin was analyzed by GPC in the same manner as in Example 1. As a result, the number average molecular weight in terms of polystyrene was 30000.

  Terpineol is further added to the terpineol solution of the (meth) acrylic resin obtained as described above and dispersed using a high-speed disperser, and 50 parts by weight of terpineol is contained with respect to 14 parts by weight of the (meth) acrylic resin. A dispersion is obtained.

  Next, 1 part by weight of glycerin having 3 hydroxyl groups and 35 parts by weight of glass powder were further added to the dispersion and sufficiently kneaded using a three roll to obtain a glass paste composition. In addition, the acrylic resin composition which did not mix | blend only 35 weight part of glass powder was obtained similarly.

(Comparative Example 2)
In the same manner as in Comparative Example 1, a glass paste composition was obtained with the formulation shown in Table 1. In addition, the acrylic resin composition which did not mix | blend only 35 weight part of glass powder was obtained similarly.

(Evaluation)
The following evaluation was performed about the glass paste composition obtained by the Example and the comparative example.

(1) Viscosity (viscosity ratio method (thixotropic evaluation method))
The viscosity at 23 ° C. of the glass paste composition was measured using a B-type viscometer (manufactured by BROOK FILED, DVII + Pro). The viscosity η ₅ rpm when the probe rotation speed was 5 rpm and η _{30 rpm} when the probe rotation speed was 30 _rpm were measured. It was determined viscosity ratio eta _{5 rpm} / eta _{30 rpm} of eta _{5 rpm} and eta _{30 rpm.}

The thixotropy of the glass paste composition was evaluated according to the following evaluation criteria.
○: Viscosity ratio η _{5 rpm} / η _{30 rpm} is 1.5 or more ×: Viscosity ratio η _{5 rpm} / η _{30 rpm} is less than 1.5 (2) Decomposability Acrylic resin composition in which the glass of Examples 1 and 2 was not blended Or an acrylic resin composition not blended with the glass of Comparative Examples 1 and 2 on a glass substrate with a thickness of 0.05 mm and an area of 100 mm × 100 mm, and using an electric furnace at 400 ° C. in the atmosphere for 30 minutes. When heat-treated, the residue on the glass substrate was visually evaluated. The case where there was no residue on the glass substrate was evaluated as good, and the case where there was a residue on the glass substrate was evaluated as defective.
The results are shown in Table 1 below.

  In Examples 1 and 2, when an acrylic resin composition is applied to a glass substrate to a thickness of 0.05 mm and heat-treated at 400 ° C. for 30 minutes in the atmosphere, residues and coloring can be eliminated on the glass substrate. . Therefore, the glass paste compositions of Examples 1 and 2 with a low content of (meth) acrylic resin can be fired at a low temperature.

Claims (6)

A solvent represented by the following formula (1) and having one hydroxyl group and one ester bond in the molecule, a (meth) acrylic resin obtained by polymerizing a polymerizable monomer in the solvent, and a hydroxyl group: An acrylic resin composition comprising an organic compound having three or more.
R ₁ COOR ₂ OH (1)
(In the formula (1), R ₁ is a linear or branched organic group having 1 to 6 carbon atoms, and R ₂ is a linear or branched organic group having 1 to 10 carbon atoms. Group.)   The acrylic resin composition according to claim 1, wherein the (meth) acrylic resin is composed mainly of (meth) acrylate having 10 or less carbon atoms.   The acrylic resin composition according to claim 1 or 2, wherein the number average molecular weight of the (meth) acrylic resin is in the range of 7000 to 120,000.  The acrylic resin composition according to any one of claims 1 to 3, and at least one powdery material selected from the group consisting of metal, glass, carbon black, metal complex, silica-based compound, and ceramics. A paste composition comprising the paste composition.   The paste composition of Claim 4 which contains the said solvent in the ratio of 40 to 60 weight% in 100 weight% of paste compositions. When the viscosity was measured at 23 ° C. using a B-type viscometer, and the viscosity eta _{5 rpm} in the rotational speed 5 rpm, the ratio eta _{5 rpm} / eta _30rpm with viscosity eta _30rpm in rotational speed 30rpm is 1.5 or more, wherein Item 6. The paste composition according to Item 4 or 5.