JP2764142B2 - Hybrid resin - Google Patents

Description

The present invention relates to a resin having excellent dispersibility such as a pigment. More specifically, the present invention relates to a resin excellent in dispersion and moisture resistance of inorganic pigments, organic pigments, magnetic iron oxide, carbon black and the like.

[Conventional technology]

In a coating material using an inorganic pigment, an organic pigment, magnetic iron oxide, carbon black or the like dispersed in a resin, it is necessary that these pigments are uniformly dispersed in the resin. For this purpose, a polar group having an interaction with a surface such as a pigment is introduced into a resin.

[Problems to be solved by the invention]

However, a resin containing a polar group sufficient to uniformly disperse a pigment or the like in the resin has a disadvantage that the hydrophilicity is increased due to containing a large amount of the polar group and the moisture resistance is poor.

Therefore, it is extremely useful if a resin having good moisture resistance can be obtained while having good dispersibility in various pigments and the like. The present invention has been made to provide such a resin.

Means for Solving the Problems The present inventors have intensively studied a resin having excellent dispersibility and good moisture resistance, and as a result, an acrylic resin having a specific polar group and a polyester which is substantially hydrophobic The inventors have found that a hybrid resin having a resin as each segment is excellent in dispersibility and moisture resistance, and have completed the present invention.

That is, the present invention (Wherein R ₁ and R ₂ are a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) and have at least one polar group represented by the following formula, and have a hydroxyl value of 5 to 200 KOHmg / g. A mixture consisting of 5-95 parts by weight of an acrylic resin and 95-5 parts by weight of a polyester resin having a hydroxyl value of 5-200 KOH mg / g in a total of 100 parts by weight was heated at a temperature of 180-280 ° C. for 10 minutes-5 hours. This is a hybrid resin in which an acrylic segment and a polyester segment are ester-bonded by a transesterification reaction.

The acrylic resin used in the present invention contains the above monomer having a polar group as a constituent component. Examples of such monomers include monocarboxylic acids such as (meth) acrylic acid, dicarboxylic acids such as itaconic acid, maleic acid, and fumaric acid, and lower monoalkyl esters thereof (meth) acrylamide, dimethylaminoethyl (meth) Examples thereof include acrylate, diethylaminoethyl (meth) acrylate, (meth) acrylonitrile, and p-nitrostyrene.

The amount of these specific polar group-containing monomers is preferably 0.1 to 50% by weight based on all the constituent monomers of the acrylic resin.

Other copolymerizable monomers include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate and the like as hydroxyl group-containing monomers. Can be used. Further, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate,
tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, tridecyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, glycidyl (meth) Esters of acrylic acid and methacrylic acid such as acrylate, α-methylglycidyl (meth) acrylate, β-methylglycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, and diethylaminoethyl (meth) acrylate can be used. Other copolymerized monomers include styrene, α-methylstyrene, vinyl toluene, vinyl acetate, vinyl propionate, methylol acrylamide, methylol methacrylamide, vinyl chloride, propylene, ethylene,
Α- olefins such as the C ₄ -C ₂₀ and the like.

The acrylic resin needs to have a hydroxyl value of 5 to 200 KOHmg / g, and more preferably 20 to 150 KOHmg / g. When the hydroxyl value is less than 5 KOHmg / g, the reaction between the acrylic resin and the polyester resin does not proceed sufficiently, the compatibility is poor, and the resin solution becomes turbid and the phases are separated. If the hydroxyl value exceeds 200 KOH mg / g, the reaction with the polyester resin will proceed rapidly, and it will be easy to form a gel, making it difficult to control the reaction. Can not be.

Such an acrylic resin can be produced by any known polymerization method such as a solution polymerization method, a suspension polymerization method, a bulk polymerization method, and an emulsion polymerization method. At that time, azobisisobutyronitrile, 4,4′-azobis (4-cyanopentanoic acid), benzoyl peroxide, t-butylperoxy-2-ethylhexanoate, cumene hydroperoxide, Potassium persulfate, hydrogen peroxide, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl)] propionamide and the like can be used, and if necessary, n-dodecylmercaptan as a chain transfer agent; Mercaptoethanol or the like can be used.

The number average molecular weight of the acrylic resin used in obtaining the resin of the present invention is 5 in the value measured by the GPC method.
It is preferably from 00 to 20,000.

Next, the acrylic resin used in the present invention needs to have a hydroxyl value of 5 to 200 KOH mg / g, and
More preferably, it is 0 KOHmg / g. This hydroxyl value is 5K
At less than OHmg / g, the reaction with the acrylic resin does not proceed sufficiently,
Poor compatibility, turbidity of resin solution, and phase separation. If the hydroxyl value exceeds 200 KOH mg / g, the reaction with the acrylic resin will proceed rapidly, and it will be easy to form a gel, making it difficult to control the reaction. Can not be.

Such polyester resins include, for example, terephthalic acid, isophthalic acid, phthalic anhydride, naphthalenedicarboxylic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, 1,10-decanedicarboxylic acid, cyclohexanedicarboxylic acid, and tricarboxylic acid as carboxylic acid components. Polycarboxylic acids such as melitic acid, maleic acid, and fumaric acid and lower alcohol esters thereof, hydroxycarboxylic acids such as paraoxybenzoic acid, and monovalent carboxylic acids such as benzoic acid can be used.

Further, as the alcohol component, for example, ethylene glycol, diethylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5
-Pentanediol, 1,6-hexanediol, 1,10-
Decanediol, 3-methyl-pentanediol, 2,
2'-diethyl-1,3-propanediol, 2-ethyl-
1,3-hexanediol, neopentyl glycol, trimethylolethane, trimethylolpropane, glycerin, pentaerythritol, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, hydrogenated bisphenol A ethylene oxide adduct, A propylene oxide adduct of hydrogenated bisphenol A can be used.

Further, if necessary, linseed oil, tung oil, safflower oil, dehydrated castor oil, cottonseed oil, coconut oil and their fatty acids can of course be used.

Such a polyester resin is obtained by a normal transesterification reaction or a direct esterification reaction of one or more of the above-mentioned carboxylic acid components and one or more of the above-mentioned alcohol components.

The number average molecular weight of the polyester resin used for obtaining the resin of the present invention is preferably from 500 to 10,000 as measured by the GPC method.

The resin of the present invention is a resin in which the polyester resin and the acrylic resin have reacted with each other, and when the polyester resin is more than 95 parts by weight or the acrylic resin is less than 5 parts by weight in a total of 10 parts by weight thereof. When the acrylic resin is more than 95 parts by weight or the polyester resin is less than 5 parts by weight, the moisture resistance is poor and the object of the present invention cannot be achieved.

The resin of the present invention is obtained by mixing 5 to 95 parts by weight of a polyester resin and 95 to 5 parts by weight of an acrylic resin so that a total of 100 parts by weight is obtained, and at a temperature of 180 to 280 ° C. for 10 minutes to 5 hours, more preferably By reacting the ester groups and hydroxyl groups present in both resins under conditions that allow transesterification for 30 minutes to 3 hours, a hybrid resin in which an acrylic segment and a polyester segment are bonded by an ester bond can be produced. The transesterification reaction does not necessarily have to proceed completely, and may only partially react.
Thereafter, a resin solution can be obtained by adding an appropriate solvent described below. By reacting a polyvalent isocyanate compound such as xylylene diisocyanate or a water adduct thereof, a trimethylolpropane adduct or an isocyanurate compound with 0.1 to 5% by weight of the resin solid, the hydroxyl groups remaining on the acrylic resin and the polyester resin are mutually reacted. The reaction can also proceed.

Examples of the solvent for the resin of the present invention include aromatic solvents such as toluene and xylene, ester solvents such as ethyl acetate, butyl acetate and cellosolve acetate, methyl ethyl ketone, methyl isobutyl ketone, ketone solvents such as cyclohexanone, n-butanol and iso- Alcohol solvents such as butanol or butyl cellosolve, dioxane,
Ether solvents such as tetrahydrofuran or the like and chlorine solvents such as tetrachloroethane or the like can be used alone or in combination.

In the present invention, the resin in which the polyester resin and the acrylic resin have partially reacted with each other becomes a uniform resin solution when dissolved in the above-mentioned solvent, and does not undergo phase separation even when left and stored. When the phases are separated to form a non-uniform solution, a uniform, smooth, and glossy coating film cannot be obtained when used as a coating material.

Further, the resin of the present invention can be used for coating by using a curing agent. Amino resins or isocyanate resins are suitable as curing agents. As amino resin,
A resin synthesized from at least one of melamine, urea, benzoguanamine, glycoluril and the like and formaldehyde, wherein part or all of a methylol group is alkyl ether by a lower alcohol such as methanol, ethanol, propanol, isopropanol, butanol and isobuanol. Is used.

As the isocyanate resin, a polyvalent isocyanate such as a polyvalent isocyanate monomer, a polyvalent isocyanate polymer, or an adduct thereof is used.

As the polyvalent isocyanate, aromatic, aliphatic or alicyclic such as tolylene diisocyanate, metaphenylene diisocyanate, naphthylene diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, dicyclohexyl propane diisocyanate, and trimethylpentane diisocyanate. A group polyvalent isocyanate is exemplified.

The amino resin and the isocyanate resin used in the above are both curing agent components that undergo a crosslinking reaction with hydroxyl groups in the resin to form a coating film.

The amount of the amino resin is preferably 5 to 50 parts by weight based on 100 parts by weight of the hybrid resin. The amount of the isocyanate resin is preferably in the range of 0.5 to 2.0 equivalents of the isocyanate group based on 1 equivalent of the hydroxyl group of the hybrid resin.

The resin of the present invention can obtain a uniform resin solution by further adding an acrylic resin and / or a polyester resin, and these additional uses are also possible. This is presumably because both resins used in the hybrid resin of the present invention partially reacted with each other, resulting in improved compatibility with both resins.

Other various materials generally used for coating materials, extender pigments, such as clay, calcium carbonate,
Barium sulfate, talc, alumina, silica, silica powder and the like can be blended and used. Also, cellulose derivatives, epoxy resins,
Petroleum resin, phenolic resin, ketone resin, synthetic rubber, unsaturated polyester resin, or natural resin such as rosin,
Alternatively, various assistants such as a synthetic resin, a leveling agent, an anti-sagging agent, an antifoaming agent, a surfactant, and a curing accelerator can also be used.

The resin of the present invention can be prepared by a method known per se.For example, the above-mentioned components are charged together with an organic solvent into a mixing and dispersing machine such as a steel mill, a pepper mill, an attritor, a sand mill, and a high-speed stirrer with blades. Can be prepared by uniformly mixing and dispersing.

The resin of the present invention can be coated on metals, plastics, films, woodwork products and the like by a conventional coating method such as spray coating, brush coating or roll coating.

〔Example〕

Next, the present invention will be specifically described with reference examples, examples, and comparative examples. All parts and percentages are by weight unless otherwise specified.

Reference Example 1 (Preparation Example of Polyester Resin) The raw materials shown in Table 1 were charged into a four-necked flask equipped with a stirrer, a thermometer, a condenser with a stack din, and a nitrogen inlet tube. The reaction was conducted while distilling off the reaction product for a period of time.
1 to A-5 were obtained.

Reference Example 2 (Preparation Example of Acrylic Resin) A four-necked flask equipped with a stirrer, a thermometer, and a condenser was charged with 80 parts of xylene and 20 parts of butanol, and heated to 120 ° C. and heated. Here, the raw materials shown in Table 2 were added dropwise over 4 hours, and further kept at the same temperature for 6 hours to obtain acrylic resins B-1 to B-6 having a solid content of 50%.

Reference Example 3 (Preparation Example of Hybrid Resin) Into the same flask as that used in Reference Example 1, the types and amounts of the polyester resin and the acrylic resin shown in Table 3 were charged, and heated and heated to obtain xylene and a reaction product. While distilling off
The temperature was raised to 220 ° C., and the reaction was performed for 1 hour. Then, cool and add the same amount of ethyl acetate and methyl ethyl ketone,
50% resin solution (hybrid resin) C-1, C-4,
C-5 and C-8 to C-10 were obtained.

In the same manner as above, except that the reaction conditions were changed to 240 ° C. for 30 minutes, resin solutions (hybrid resins) C-2 and C-3 having a solid content of 50% were obtained. Furthermore, resin solutions (hybrid resin) C-6 and C-7 having a solid content of 50% were obtained in exactly the same manner as above except that the reaction conditions were changed to 180 ° C. for 3 hours.

Examples 1 to 5 Hybrid resins C-1 to C-3 and C obtained in Reference Example 3
Magnetic iron oxide (specific surface area 35 m ² /
g) 150 parts were added and mixed in a ball mill for 15 hours. Then, Olester P-49 [trade name, manufactured by Mitsui Toatsu Chemicals, Inc.
5 parts of toluene diisocyanate-based polyisocyanate, solid content of 75%] was added and mixed well. The obtained magnetic coating liquid was applied on a polyester film with an applicator so as to have a dry film thickness of 8 μm.
It dried at 30 degreeC for 30 minutes, and obtained the coating film.

In order to evaluate the dispersibility of the magnetic iron oxide, the glossiness of the obtained film surface was measured. Further, the moisture resistance of this film was evaluated in three steps as described in the footnote of Table-4.
Table 4 shows the results.

Comparative Examples 1 to 3 In Example 1, except that the hybrid resin C-4, C-5 or C-8 obtained in Reference Example 3 was used, the same operation was performed to obtain a magnetic coating liquid and further a coated film. The films were evaluated. Table 4 shows the results.

Comparative Example 4 A magnetic coating liquid was obtained in the same manner as in Example 1, except that the hybrid resin C-9 obtained in Reference Example 3 was used. However, the coating liquid phase-separated and could not be uniformly applied on the polyester film, and the subsequent operation was stopped.

Comparative Example 5 A magnetic coating liquid was obtained in the same manner as in Example 1, except that the hybrid resin C-10 obtained in Reference Example 3 was used. However, a gel substance was generated in the coating liquid, and the coating liquid could not be uniformly applied on the polyester film, and the subsequent operation was stopped.

[Effects of the Invention] As shown in Examples 1 to 5, the resin of the present invention has excellent dispersibility and moisture resistance.

Continuation of the front page (56) References JP-A-48-890 (JP, A) JP-A-63-278973 (JP, A) JP-A-1-156374 (JP, A) JP-A-62-260869 (JP) JP-A-49-40348 (JP, A) JP-A-51-119043 (JP, A) JP-A-51-16338 (JP, A) JP-A-1-132636 (JP, A) 49-30517 (JP, B1) JP 46-35367 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08G 81/00-81/02 C08L 33/00-33 / 26 C08L 67/00-67/08 C09D 133/00-133/26 C09D 167/00-167/08 C09D 187/00

Claims (1)

(57) [Claims] (1) (Wherein R ₁ and R ₂ are a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) and have at least one polar group represented by the following formula, and have a hydroxyl value of 5 to 200 KOHmg / g. A mixture consisting of 5-95 parts by weight of an acrylic resin and 95-5 parts by weight of a polyester resin having a hydroxyl value of 5-200 KOH mg / g in a total of 100 parts by weight was heated at a temperature of 180-280 ° C. for 10 minutes-5 hours. A hybrid resin in which an acrylic segment and a polyester segment are ester-bonded by a transesterification reaction.