WO2013012031A1 - Aqueous polyurethane resin dispersion and use thereof - Google Patents

Abstract

Provided is an aqueous polyurethane resin dispersion which has a short manufacturing time and excellent storage stability, and which after being cured by irradiation with active energy rays (e.g. ultraviolet rays), forms a coating with a high degree of hardness and excellent adhesive properties to a base material. Specifically provided is an aqueous polyurethane resin dispersion composition obtained by dispersing, in an aqueous medium, at least a polyurethane resin (A) having polymerizable unsaturated bonds and a compound (B) having polymerizable unsaturated bonds, said aqueous polyurethane resin dispersion being characterized in that the polyurethane resin (A) having polymerizable unsaturated bonds is obtained by reacting at least a polyol (a), an acidic group-containing polyol (b), a polyisocyanate (c), and a primary-hydroxyl-group-containing (meth) acrylate (d); and in that the total mass of the primary-hydroxyl-group-containing (meth) acrylate (d) and the compound (B) having polymerizable unsaturated bonds is 60-80 weight% of the whole solid resin content. Also provided are a photo-curable composition, a coating composition, and a coating-agent composition each comprising this aqueous polyurethane resin dispersion.

Description

Aqueous polyurethane resin dispersion and use thereof

The present invention relates to an aqueous urethane resin dispersion that can be cured by active energy rays such as ultraviolet light and its use.

Polycarbonate polyol is a useful compound to be a raw material of polyurethane resin, and can react with an isocyanate compound to produce polyurethane resin used for rigid foam, flexible foam, paint, adhesive, synthetic leather, ink binder, etc. . In addition, it is known that a coating film obtained by applying an aqueous polyurethane resin dispersion using polycarbonate polyol as a raw material is excellent in light resistance, weather resistance, heat resistance, hydrolysis resistance and oil resistance (patent document 1).

Above all, a coating film obtained by applying an aqueous urethane resin dispersion using an aliphatic polycarbonate polyol is known to be used as an undercoat agent because the adhesion to a substrate and the blocking resistance are improved. (See Patent Document 2). However, when only an aliphatic polycarbonate polyol is used as a raw material, the hardness of the coating film obtained from the aqueous polyurethane resin dispersion and the adhesion to a substrate are, for example, automobile interior materials, mobile phone casings, home appliances There is a problem in that it is not sufficient in the field of paints of synthetic resin molded articles such as casings, personal computer casings, decorative films, optical films, floorings such as floorings, and the field of coating agents.

In order to improve the hardness and durability of the coating, an aqueous polyurethane resin dispersion using a polycarbonate polyol having an alicyclic structure has also been proposed (see Patent Documents 3, 4 and 5). However, when a polycarbonate polyol having an alicyclic structure is used, the dispersibility of the polyurethane resin in the aqueous medium is deteriorated, and there is a problem that the handleability and stability of the aqueous polyurethane resin dispersion are deteriorated. In addition, for example, with respect to the aqueous polyurethane resin dispersion, for example, Patent Document 3 has not clarified the influence on the adhesion, and the dispersion in the aqueous medium was not satisfactory. .

With regard to coating hardness, in the case of hard coating applications, a coating hardness generally requires a pencil hardness of 2H or more. Therefore, the use of urethane (meth) acrylates has also been studied for the purpose of increasing the film hardness, and, for example, an aqueous radiation-curable composition comprising a (meth) acrylated polyurethane prepolymer and an ethylenically unsaturated compound ( U.S. Pat. No. 5,075,015 and aqueous radiation curable compositions comprising high molecular weight ethylenically unsaturated polyurethanes and low molecular weight ethylenically unsaturated polyurethanes have been proposed.

Unexamined-Japanese-Patent No. 10-120757 JP 2005-281544 A Japanese Patent Application Laid-Open No. 6-248046 International Publication 2009/145242 International Publication 2009/004951 Japanese Patent Publication No. 2009-533504 International Publication 2009/147092

However, the composition specifically disclosed in Patent Document 6 uses a bifunctional (meth) acrylate having a secondary hydroxyl group or has a hydroxyl value of 80 mg KOH / g in the production of a (meth) acrylated polyurethane prepolymer. Less than DPHA is used in small amounts. Therefore, it was found that it is necessary to prolong the reaction time under heating when producing the prepolymer, and the problem of yellowing occurs even when using a non-yellowing isocyanate having no aromatic ring. In addition, when using a large amount of DPHA having a hydroxyl value of less than 80 mg KOH / g or not using a bifunctional (meth) acrylate having a secondary hydroxyl group in order to shorten the reaction time, the storage stability of the aqueous radioactive composition It was found that when the coating film of the composition was formed on a polymethyl methacrylate resin (PMMA resin), the adhesion was not sufficient.
Further, the composition specifically disclosed in Patent Document 7 does not adhere at all to a (meth) acrylic resin used for various applications as a transparent material, and there is a problem that the pencil hardness is too low. I understood it.

An object of the present invention is to provide an aqueous polyurethane resin dispersion in which production time is short, storage stability is excellent, and a coating film after curing by active energy ray (for example, ultraviolet light) irradiation has high hardness. Further, according to the present invention, the coating film after curing by active energy ray (for example, ultraviolet light) irradiation is a substrate, particularly (meth) acrylic resin (for example, polymethyl methacrylate resin (PMMA resin)) and acrylonitrile-butylene- It is an object of the present invention to provide an aqueous polyurethane resin dispersion having high adhesion to a styrene resin (ABS resin).

As a result of conducting various studies to overcome the problems of the prior art described above, the present inventors have found that the polyurethane resin (A) having a polymerizable unsaturated bond is a polyol (a) and an acid group-containing polyol (A). b) obtained by reacting at least a polyisocyanate (c) and a primary hydroxyl group-containing (meth) acrylate (d), wherein a polymerizable unsaturated bond is added to the polyurethane resin (A) The problem is solved by the aqueous polyurethane resin dispersion in which the total amount with the primary hydroxyl group-containing (meth) acrylate (d) is 60 to 80% by weight of the total resin solid content. With the finding that it can be achieved, the present invention has been achieved. Here, resin solid content means the sum total of a polyurethane resin (A) and the compound (B) which has a polymerizable unsaturated bond. However, the resin solid content does not contain a neutralizing agent such as a base or an alkali used to neutralize the acidic group of the acidic group-containing polyol (b).

The present invention (1) is an aqueous polyurethane resin dispersion composition in which at least a polyurethane resin (A) having a polymerizable unsaturated bond and a compound (B) having a polymerizable unsaturated bond are dispersed in an aqueous medium. The object,
The polyurethane resin (A) having a polymerizable unsaturated bond comprises at least a polyol (a), an acidic group-containing polyol (b), a polyisocyanate (c) and a primary hydroxyl group-containing (meth) acrylate (d) It is obtained by reaction,
An aqueous polyurethane resin, characterized in that the total amount of primary hydroxyl group-containing (meth) acrylate (d) and the compound (B) having a polymerizable unsaturated bond is 60 to 80% by weight of the total resin solid content. It relates to the dispersion.
The present invention (2) relates to the aqueous polyurethane resin dispersion of the present invention (1), wherein the polyol (a) is a polycarbonate diol.
The total amount of the primary hydroxyl group-containing (meth) acrylate (d) and the compound (B) having a polymerizable unsaturated bond is 65 to 75% by weight of the total resin solid content. The invention relates to an aqueous polyurethane resin dispersion of the invention (1) or (2).
The invention (4) is any of the inventions (1) to (3), wherein the compound (B) having a polymerizable unsaturated bond is a compound having three or more (meth) acryloyl groups in one molecule. Aqueous polyurethane resin dispersion of
In the present invention (5), the compound (B) having a polymerizable unsaturated bond is an alkylene oxide-modified pentaerythritol tetra (meth) acrylate, an alkylene oxide-modified trimethylolpropane tri (meth) acrylate, an alkylene oxide-modified ethylene glycol di ( The aqueous polyurethane resin dispersion according to any one of the present inventions (1) to (3), which is at least one member selected from the group consisting of meta) acrylates.
In the invention (6), the aqueous polyurethane resin dispersion according to any one of the inventions (1) to (5), wherein the compound (B) having a polymerizable unsaturated bond is an alkylene oxide modified pentaerythritol tetra (meth) acrylate It relates to the body.
In the present invention (7), the primary hydroxyl group-containing (meth) acrylate (d) is subjected to a reaction for obtaining a polyurethane resin (A) as a mixture with a (meth) acrylate inert to isocyanato groups. The present invention relates to the aqueous polyurethane resin dispersion of any of the present inventions (1) to (6).
The present invention (8) is characterized in that the primary hydroxyl group-containing (meth) acrylate (d) is dipentaerythritol hexa (meth) acrylate having a hydroxyl value of 80 mg KOH / g or more and 120 mg KOH / g or less and dipentaerythritol penta (meth) acrylate The aqueous polyurethane resin dispersion according to any one of the present inventions (1) to (7), which is subjected to a reaction for obtaining a polyurethane resin (A) as a mixture of
The present invention (9) is a mixture of pentaerythritol tetra (meth) acrylate and pentaerythritol tri (meth) acrylate having a primary hydroxyl group-containing (meth) acrylate (d) and having a hydroxyl value of 100 mg KOH / g to 280 mg KOH / g. The present invention relates to the aqueous polyurethane resin dispersion of any of the present inventions (1) to (7), which is subjected to the reaction for obtaining the polyurethane resin (A).
The present invention (10) relates to the photocurable composition according to any one of the present inventions (1) to (9), which contains a photopolymerization initiator.
The present invention (11) relates to a coating composition containing the aqueous polyurethane resin dispersion of any of the present inventions (1) to (9).
The present invention (12) relates to the paint composition of the present invention (11), which is for (meth) acrylic resin or acrylonitrile-butylene-styrene resin.
The present invention (13) relates to a coating composition comprising the aqueous polyurethane resin dispersion of any of the present inventions (1) to (9).
The present invention (14) relates to the coating agent composition of the present invention (13), which is for (meth) acrylic resin or acrylonitrile-butylene-styrene resin.

According to the present invention, an aqueous polyurethane resin dispersion is provided which has a short production time, excellent storage stability, and a high hardness of a coating film after curing by active energy ray (for example, ultraviolet light) irradiation. Further, according to the present invention, the coating film after curing by active energy ray (for example, ultraviolet light) irradiation has high adhesion to a substrate, particularly to (meth) acrylic resin and acrylonitrile-butylene-styrene resin (ABS resin) An aqueous polyurethane resin dispersion is provided.

The present invention is an aqueous polyurethane resin dispersion obtained by dispersing at least a polyurethane resin (A) having a polymerizable unsaturated bond and a compound (B) having a polymerizable unsaturated bond in an aqueous medium,
A polyurethane resin (A) having a polymerizable unsaturated bond comprises a polyol (a), an acidic group-containing polyol (b), a polyisocyanate (c), and a primary hydroxyl group-containing (meth) acrylate (d), The present invention relates to an aqueous polyurethane resin dispersion obtained at least by reaction.

<Polyurethane resin having a polymerizable unsaturated bond (A)>
<< Polyol (a) >>
As a polyol (a), high molecular weight polyol and low molecular weight polyol can be used, for example. It is preferable to use a high molecular weight diol or a low molecular weight diol from the easiness of manufacture of the aqueous polyurethane resin dispersion.

The high molecular weight diol is not particularly limited, but preferably has a number average molecular weight of 400 to 8,000. When the number average molecular weight is in this range, an appropriate viscosity and good handleability can be easily obtained. It is easy to ensure the performance as a soft segment, and when a coating is formed using the aqueous polyurethane resin dispersion containing the obtained polyurethane resin, it is easy to suppress the occurrence of cracking, and further, polyisocyanate (c) and The reaction property of the polyurethane resin (A) can be efficiently carried out. The polyol (a) more preferably has a number average molecular weight of 400 to 4,000.

In this specification, a number average molecular weight is taken as the number average molecular weight computed based on the hydroxyl value measured based on JISK1577. Specifically, the hydroxyl value is measured, and it is calculated by (56.1 × 1000 × number of valence) / hydroxyl value [mg KOH / g] by an end group determination method. In the above formula, the valence is the number of hydroxyl groups in one molecule.

Examples of the high molecular weight diol include polycarbonate diol, polyester diol, polyether diol and the like. From the viewpoints of light resistance, weather resistance, heat resistance, hydrolysis resistance and oil resistance of an aqueous polyurethane resin dispersion containing the obtained polyurethane resin and a coating film obtained therefrom, polycarbonate diol is preferable.

Among polycarbonate diols, the diol component is preferably an aliphatic diol and / or an alicyclic diol, the viscosity of the obtained polyurethane resin is low, the handling is easy, and the dispersibility in an aqueous medium is good. From the point of view, it is more preferable that the diol component is an aliphatic diol having no alicyclic structure.

Polycarbonate polyols are obtained by reacting one or more polyol monomers with a carbonate or phosgene. The polycarbonate polyol obtained by making one or more types of polyol monomer and carbonate ester react is preferable from the point which is easy to manufacture and from the point which does not by-produce a terminal chlorinated compound.

The polyol monomer is not particularly limited, and examples thereof include aliphatic polyol monomers, polyol monomers having an alicyclic structure, aromatic polyol monomers, polyester polyol monomers, and polyether polyol monomers.

The aliphatic polyol monomer is not particularly limited. For example, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1 Straight-chain aliphatic diols such as 1,8-octanediol and 1,9-nonanediol; 2-methyl-1,3-propanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5 And branched aliphatic diols such as pentanediol and 2-methyl-1,9-nonanediol; and trifunctional or higher polyhydric alcohols such as trimethylolpropane and pentaerythritol.

The polyol monomer having an alicyclic structure is not particularly limited, and examples thereof include 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,3-cyclopentanediol, 1, and the like. Alicyclic ring in the main chain such as 4-cycloheptanediol, 2,5-bis (hydroxymethyl) -1,4-dioxane, 2,7-norbornanediol, tetrahydrofuran dimethanol, 1,4-bis (hydroxyethoxy) cyclohexane, etc. The diol etc. which have a formula structure are mentioned.

The aromatic polyol monomer is not particularly limited, and, for example, 1,4-benzenedimethanol, 1,3-benzenedimethanol, 1,2-benzenedimethanol, 4,4'-naphthalenedimethanol, 3,4 '-Naphthalene dimethanol etc. may be mentioned.

The polyester polyol monomer is not particularly limited, but, for example, a polyester polyol of hydroxycarboxylic acid and diol such as polyester polyol of 6-hydroxycaproic acid and hexanediol, and a dicarboxylic acid such as polyester polyol of adipic acid and hexanediol And polyester polyols and the like.

The polyether polyol monomer is not particularly limited, and examples thereof include polyalkylene glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol, and the like.

The carbonate is not particularly limited, and examples thereof include aliphatic carbonates such as dimethyl carbonate and diethyl carbonate, aromatic carbonates such as diphenyl carbonate, cyclic carbonates such as ethylene carbonate, and the like. In addition, phosgene etc. which can produce polycarbonate polyol can also be used. Among them, aliphatic carbonates are preferable, and dimethyl carbonate is particularly preferable, from the easiness of production of polycarbonate polyol.

As a method for producing a polycarbonate polyol from a polyol monomer and a carbonate, for example, a carbonate and an excess number of moles of the polyol relative to the number of moles of the carbonate are added to a reactor, and the temperature is 160 to 200 ° C. The reaction is carried out at a pressure of about 50 mmHg for 5 to 6 hours, and then at a pressure of several mmHg or less at 200 to 220 ° C. for several hours. It is preferable to make it react, extracting the byproduct alcohol out of the system in said reaction. At that time, when the carbonate ester is azeotropically formed with the by-produced alcohol and thus comes out of the system, an excess amount of the carbonate ester may be added. In the above reaction, a catalyst such as titanium tetrabutoxide may be used.

The polyester diol is not particularly limited. For example, polyethylene adipate diol, polybutylene adipate diol, polyethylene butylene adipate diol, polyhexamethylene isophthalate adipate diol, polyethylene succinate diol, polybutylene succinate diol, polyethylene sebacate diol And polybutylene sebacate diol, poly-ε-caprolactone diol, poly (3-methyl-1,5-pentylene adipate) diol, polycondensate of 1,6-hexane diol and dimer acid, and the like.

The polyether diol is not particularly limited, and examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethylene oxide and propylene oxide, random copolymer and block copolymer of ethylene oxide and butylene oxide, and the like. Furthermore, a polyether polyester polyol having an ether bond and an ester bond may be used.

The low molecular weight diol is not particularly limited, and examples thereof include those having a number average molecular weight of 60 or more and less than 400. For example, ethylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol , 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol Aliphatic diols having 2 to 9 carbon atoms such as diethylene glycol, triethylene glycol and tetraethylene glycol; 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanediol, 1,4-bis (Hydroxyethyl) cyclohexane, 2,7-norbornanediol, tetrahydrofuran Mention may be made of diols having a C 6-12 alicyclic structure such as methanol and 2,5-bis (hydroxymethyl) -1,4-dioxane, and the like. Furthermore, as the low molecular weight polyol, a low molecular weight polyhydric alcohol such as trimethylolpropane, pentaerythritol, or sorbitol may be used.

The polyol (a) may be used alone or in combination of two or more.

<< Acid group-containing polyol (b) >>
The acidic group-containing polyol (b) contains two or more hydroxyl groups and one or more acid groups in one molecule. As an acidic group, a carboxy group, a sulfonic acid group, a phosphoric acid group, phenolic hydroxyl group etc. are mentioned. As the acidic group-containing polyol (b), one containing a compound having two hydroxyl groups and one carboxy group in one molecule is preferable. The acidic group-containing polyol (b) may be used alone or in combination of two or more.

Specific examples of the acidic group-containing polyol (b) include dimethylolalkanoic acids such as 2,2-dimethylol propionic acid and 2,2-dimethylol butanoic acid, N, N-bishydroxyethyl glycine N, N-bishydroxyethylalanine, 3,4-dihydroxybutanesulfonic acid, 3,6-dihydroxy-2-toluenesulfonic acid and the like can be mentioned. Among them, dimethylolalkanoic acid having 4 to 12 carbon atoms containing two methylol groups is preferable from the viewpoint of easy availability, and among dimethylolalkanoic acids, 2,2-dimethylol propionic acid is more preferable.

In the present invention, the total number of hydroxyl group equivalents of the polyol (a) and the acidic group-containing polyol (b) is preferably 120 to 600. If the number of hydroxyl group equivalents is in this range, the production of an aqueous polyurethane resin dispersion containing the obtained polyurethane resin is easy, and a coating film excellent in hardness is easily obtained. From the viewpoint of the storage stability of the aqueous polyurethane resin dispersion obtained and the hardness of the coating film obtained by coating, the hydroxyl equivalent number is preferably 130 to 600, more preferably 150 to 500, and particularly preferably 170 to 400. is there.

The number of hydroxyl group equivalents can be calculated by the following formulas (1) and (2).
Number of hydroxyl group equivalents of each polyol = molecular weight of each polyol / number of hydroxyl groups of each polyol (1)
Total number of hydroxyl group equivalents of total polyol = M / total number of moles of polyol ... (2)
In the case of the polyurethane resin (A), in the formula (2), M is [[number of hydroxyl group equivalents of polyol (a) × number of moles of polyol (a)] + [number of hydroxyl group equivalents of acidic group-containing polyol (b) × The number of moles of the acidic group-containing polyol (b)] is shown.

<< Polyisocyanate (c) >>
The polyisocyanate (c) is not particularly limited, and examples thereof include aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate and the like.

Specific examples of the aromatic polyisocyanate include 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate, 4,4'- Diphenylmethane diisocyanate (MDI), 2,4-diphenylmethane diisocyanate, 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4 Examples thereof include '-diisocyanatodiphenylmethane, 1,5-naphthyl diisocyanate, 4,4 ′, 4 ′ ′-triphenylmethane triisocyanate, m-isocyanatophenylsulfonyl isocyanate, p-isocyanatophenylsulfonyl isocyanate and the like.

Specific examples of aliphatic polyisocyanates include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecanetriisocyanate, and 2,2,4-trimethylhexamethylene diisocyanate. Lysine diisocyanate, 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexano And the like.

Specific examples of alicyclic polyisocyanates include isophorone diisocyanate (IPDI), 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), bis (2 And -isocyanatoethyl) -4-dichlorohexene-1,2-dicarboxylate, 2,5-norbornane diisocyanate, 2,6-norbornane diisocyanate and the like.

The number of isocyanato groups per one molecule of polyisocyanate is generally two, but polyisocyanates having three or more isocyanato groups such as triphenylmethane triisocyanate are also used to the extent that the polyurethane resin in the present invention does not gel. be able to.

Among polyisocyanates, an alicyclic polyisocyanate having an alicyclic structure is preferable from the viewpoint that hardness after curing by active energy rays (for example, ultraviolet rays) is increased, and isophorone diisocyanate from the viewpoint of easy control of reaction. Particular preference is given to (IPDI), 4,4′-dicyclohexylmethane diisocyanate (hydrogenated MDI).

The polyisocyanate may be used alone or in combination of two or more.

<< First-class hydroxyl group-containing (meth) acrylate (d) >>
The primary hydroxyl group-containing (meth) acrylate is not particularly limited as long as it is a meta (acrylate) compound having a primary hydroxyl group. The "primary hydroxyl group" in the present specification means a hydroxyl group in which an oxygen atom of a hydroxyl group is bonded to a methylene group. In the present specification, “(meth) acryloyl compound”, “(meth) acrylate compound”, and “(meth) acrylate” are all concepts including an acryloyl group-containing compound and a methacryloyl group-containing compound. And may have both an acryloyl group and a methacryloyl group.

As primary hydroxyl group-containing (meth) acrylate (d), 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, glycerin di (meth) acrylate, diglycerin Tri (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, sorbitol penta (meth) acrylate, glycerin mono (meth) acrylate, diglycerin mono (meth) acrylate, pentaerythritol mono (meth) acrylate ) Acrylate, Sorbitol mono (meth) acrylate diglycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, dipentaerythritol di (meth) acrylate, Pentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, sorbitol di (meth) acrylate, sorbitol tri (meth) acrylate, sorbitol tetra (meth) acrylate.

Among them, one having 3 or more (meth) acryloyl groups in one molecule is preferable from the viewpoint that hardness after curing by active energy rays (for example, ultraviolet rays) becomes high. As such (meth) acrylates, diglycerin tri (meth) acrylate, pentaerythritol tri (meth) acrylate, sorbitol penta (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, Examples include dipentaerythritol penta (meth) acrylate, sorbitol tri (meth) acrylate, and sorbitol tetra (meth) acrylate.

Among primary hydroxyl group-containing (meth) acrylates in which the number of (meth) acryloyl groups in one molecule is 3 or more, it is possible to shorten the production time of the polyurethane resin (A). The (meth) acrylate compound which has is more preferable. Examples of such (meth) acrylates include pentaerythritol tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, and dipentaerythritol penta (meth) acrylate. From the viewpoint of coating film hardness and production time, dipentaerythritol tetra (meth) acrylate and dipentaerythritol penta (meth) acrylate are particularly preferable.

The primary hydroxyl group-containing (meth) acrylate (d) may be used alone or in combination of two or more.

As the primary hydroxyl group-containing (meth) acrylate, a commercially available product may be used as it is.

The primary hydroxyl group-containing (meth) acrylate can be subjected to the reaction for obtaining the polyurethane resin (A) as a mixture with (meth) acrylate which is inactive to the isocyanato group. The (meth) acrylate inert to the unreacted isocyanato group can constitute the compound (B) having a polymerizable unsaturated bond.

As a mixture, dipentaerythritol tetra (meth) acrylate and dipentaerythritol penta (meth) acrylate are commercially available dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) Mixtures of acrylates, mixtures of dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate, etc. may be mentioned. Dipentaerythritol hexa (meth) acrylate corresponds to (meth) acrylate which is inert to the isocyanato group.

A mixture of dipentaerythritol tetra (meth) acrylate and dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate, or a mixture of dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate The hydroxyl value is preferably 80 mg KOH / g or more. If the hydroxyl value is in this range, it is possible to easily avoid the problem that the production of the polyurethane resin (A) takes time and the resin becomes colored. The hydroxyl value is preferably 80 to 130 mg KOH / g from the viewpoint of suppressing the increase in viscosity during the production of the polyurethane resin (A) and avoiding gelation. The hydroxyl value is 85 to 120 mg KOH / g. Examples of a mixture of dipentaerythritol hexa (meth) acrylate and dipentaerythritol penta (meth) acrylate having a hydroxyl value of 80 mg KOH / g or more include, for example, Alonics M403 manufactured by Toagosei Co., Ltd.

Further, as a mixture, a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate can also be used. Pentaerythritol tetraacrylate corresponds to a primary hydroxyl group-free (meth) acrylate. In this case, the hydroxyl value is preferably 100 to 280 mg KOH / g. If the hydroxyl value is in this range, it is possible to easily avoid the problem that the production of the polyurethane resin (A) takes time and the resin becomes colored. The hydroxyl value is preferably 120 to 250 mg KOH / g from the viewpoint of suppressing the viscosity increase at the production of the polyurethane resin (A) and avoiding the gelation. A further preferred hydroxyl value is 140 to 220 mg KOH / g. Examples of the mixture of pentaerythritol triacrylate having a hydroxyl value of 100 to 280 mg KOH / g and pentaerythritol tetraacrylate include Alonix M305 and M306 manufactured by Toagosei Co., Ltd.

The hydroxyl value of the above mixture is measured by the method described in JIS K 0070.

The amount of the primary hydroxyl group-containing (meth) acrylate (d) is preferably 25 to 70% by weight in the weight of the polyurethane resin (A) having a polymerizable unsaturated bond. Within this range, the reaction time of the primary hydroxyl group-containing (meth) acrylate (d) and the isocyanato group is within an appropriate time, and the hardness of the coating after curing of active energy rays (for example, ultraviolet light) is within an appropriate range. And the storage stability of the aqueous polyurethane resin dispersion containing the obtained polyurethane resin can be well maintained. The primary hydroxyl group-containing (meth) acrylate (d) is more preferably 30 to 70% by weight.

Mixture of primary hydroxyl group-containing (meth) acrylate (d) with (meth) acrylate inactive to isocyanato group (specifically, dipentaerythritol tetra (meth) acrylate and dipentaerythritol penta (meth) acrylate and When used as a mixture of dipentaerythritol hexa (meth) acrylate, a mixture of dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate, a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate, etc.) The amount of the mixture is preferably 50 to 80% by weight, more preferably 60 to 80% by weight in the weight of the polyurethane resin (A) having a polymerizable unsaturated bond.

<Polyurethane resin having a polymerizable unsaturated bond (A)>
The polyurethane resin (A) having a polymerizable unsaturated bond (hereinafter also referred to as "polyurethane resin (A)") contains at least a polyol (a), an acidic group-containing polyol (b), and a polyisocyanate (c) It is a polyurethane resin obtained by making it react with primary hydroxyl group containing (meth) acrylate (d). The polymerizable unsaturated bond can be derived from the (meth) acryloyl group of the primary hydroxyl group-containing (meth) acrylate (d).

The ratio of the number of moles of isocyanato groups of polyisocyanate (c) to the number of moles of total hydroxyl groups of polyol (a), acidic group-containing polyol (b) and primary hydroxyl group-containing (meth) acrylate (d) is 0 1 to 0.9 is preferred.

Within this range, the problem of an increase in reaction time can be easily avoided by the fact that the number of moles of hydroxyl groups is too small, while the unreacted polyol (a) and the acid group-containing group are that by the number of moles of hydroxyl groups being too large. It is possible to easily avoid the problem that the polyol (b) and the primary hydroxyl group-containing (meth) acrylate (d) remain in a large amount and the storage stability is lowered. The ratio of the number of moles of isocyanato groups of polyisocyanate (c) to the number of moles of total hydroxyl groups is preferably 0.15 to 0.8, particularly preferably 0.2 to 0.7.

The reaction of the polyol (a), the acidic group-containing polyol (b), the polyisocyanate (c) and the primary hydroxyl group-containing (meth) acrylate (d) is (a), (b), (d) in random order It may be reacted with c), or two or more species may be mixed and reacted with (c). The primary hydroxyl group-containing (meth) acrylate (d) may be reacted as a mixture with an isocyanato group-inert (meth) acrylate.

When reacting the polyol (a), the acidic group-containing polyol (b), the primary hydroxyl group-containing (meth) acrylate (d) and the polyisocyanate (c), a catalyst can also be used.

The catalyst is not particularly limited. For example, salts of metals and organic and inorganic acids such as tin (tin) catalysts (trimethyltin laurate, dibutyltin dilaurate, etc.) and lead catalysts (lead octylate etc.), and organometallics Derivatives, amine catalysts (triethylamine, N-ethylmorpholine, triethylenediamine etc.), diazabicycloundecene catalysts, etc. may be mentioned. Among them, dibutyltin dilaurate and dioctyltin dilaurate are preferable from the viewpoint of reactivity.

The reaction temperature at the time of reaction is not particularly limited, but 40 to 120 ° C. is preferable. Within this range, the solubility of the raw material is good, the viscosity of the resulting urethane resin (A) is appropriate, and stirring can be carried out sufficiently, and the (meth) acryloyl group causes a polymerization reaction to gelate, It is less likely to cause problems such as side reaction of the isocyanato group. The reaction temperature is more preferably 60 to 100 ° C.

When reacting the primary hydroxyl group-containing (meth) acrylate (d) with the polyisocyanate (c), the unnecessary consumption of the (meth) acryloyl group of the primary hydroxyl group-containing (meth) acrylate (d) is avoided Therefore, it is preferable to carry out in the presence of oxygen.

Moreover, in order to avoid unnecessary consumption of the (meth) acryloyl group of the primary hydroxyl group-containing (meth) acrylate (d), a polymerization inhibitor may be added to the reaction system.

As a polymerization inhibitor, hydroquinone, hydroquinone monomethyl ether, benzoquinone, 2-tert-butyl hydroquinone, p-tert-butyl catechol, 2,5-bis (1,1,3,3-tetramethylbutyl) hydroquinone, 2, Quinone type polymerization inhibitors such as 5-bis (1,1-dimethylbutyl) hydroquinone; 2,6-bis (1,1-dimethylethyl) -4-methylphenol, 2,6-di-tert-butylphenol, 2 2,4-di-tert-butylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,4,6-tri-tert-butylphenol etc. Alkylphenol polymerization inhibitors; aromatic amine polymerization inhibitors such as phenothiazine; alkylated diphenylamines, N, N'-diphenyl- p-phenylenediamine, phenothiazine, 4-hydroxy-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1,4-dihydroxy-2,2,6 6,6-Tetramethylpiperidine, 1-hydroxy-4-benzoyloxy-2,2,6,6-tetramethylpiperidine, di-p-fluorophenylamine, 2,2,6,6-tetramethylpiperidine- Amine polymerization inhibitors such as 1-oxyl (TEMPO); 2,2-diphenylpicrylhydrazyl (DPPH), tri-p-nitrophenylmethyl, N- (3N-oxyanilino-1,3-dimethylbutylidene) -Quaternary ammonium chlorides such as aniline oxide, benzyltrimethyl ammonium chloride; diethyl hydroxy Organic acids such as amines, cyclic amides, nitrile compounds, substituted ureas, benzothiazoles, bis- (1,2,2,6,6 pentamethyl-4-pipedinyl) sepackates, lactic acid, oxalic acid, citric acid, tartaric acid, benzoic acid and the like Organic phosphine, phosphite and the like can be mentioned. These may be individual or may be used in combination of two or more. In particular, by using a quinone type polymerization inhibitor and an alkylphenol type polymerization inhibitor in combination, the consumption due to the polymerization of the (meth) acryloyl group can be further reduced.

The amount of the polymerization inhibitor is 0.001 to 1 with respect to a total of 100 parts by weight of the polyol (a), the acidic group-containing polyol (b), the primary hydroxyl group-containing (meth) acrylate (d) and the polyisocyanate (c) It may be part by weight, preferably 0.01 to 0.5 parts by weight.

The reaction with the polyol (a), the acidic group-containing polyol (b), the primary hydroxyl group-containing (meth) acrylate (d) and the polyisocyanate (c) may be carried out without a solvent or in the presence of an organic solvent You may do it. Examples of the organic solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, dioxane, dimethylformamide, dimethyl sulfoxide, N-methyl pyrrolidone, N-ethyl pyrrolidone, ethyl acetate and the like. Among them, acetone, methyl ethyl ketone and ethyl acetate are preferable because they can be removed by heating and pressure reduction after dispersing the polyurethane resin (A) in water. N-methyl pyrrolidone and N-ethyl pyrrolidone are preferable because they work as a film-forming aid when producing a coating film using the aqueous polyurethane resin dispersion containing the obtained polyurethane resin.

The amount of the organic solvent is preferably 0 to 2 by weight based on the total amount of the polyol (a), the acidic group-containing polyol (b), the primary hydroxyl group-containing (meth) acrylate (d) and the polyisocyanate (c). The ratio is preferably 0. 0, more preferably 0.05 to 0.7. Within this range, the step of removing the organic solvent takes time, the dispersibility of the obtained polyurethane resin in water is good, and the organic solvent can be used in the coating film produced using the aqueous polyurethane resin dispersion. It is possible to avoid the problem that the solvent remains and the physical properties of the coating film are degraded.

<Compound (B) Having a Polymerizable Unsaturated Bond>
The aqueous polyurethane resin dispersion of the present invention comprises a compound (B) having a polymerizable unsaturated bond. The compound (B) having a polymerizable unsaturated bond is preferably a radically polymerizable compound. The radical polymerizable compound is not particularly limited as long as it polymerizes in the coexistence of a photo radical generator or in the coexistence of a heat radical generator, but a (meth) acrylate compound is preferable.

Examples of the radically polymerizable compound include (meth) acrylate compounds of monomers, polyurethane (meth) acrylate compounds, polyester (meth) acrylate compounds, and polyalkylene (meth) acrylate compounds.

Examples of (meth) acrylate compounds of monomers include mono (meth) acrylates, di (meth) acrylates, tri (meth) acrylates, tetra (meth) acrylates, penta (meth) acrylates, poly (meth) acrylates, etc. Meta) acrylate is mentioned.

As mono (meth) acrylate, for example, acryloyl morpholine, 2-ethylhexyl (meth) acrylate, styrene, methyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dodecyl (meth) acrylate, cyclohexyl (meth) acrylate, di- Cyclopentenyl (meth) acrylate, dicyclopentenyl oxyethyl (meth) acrylate, phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, N-vinyl-2-pyrrolidone, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono ( Meta) acrylate, polyethylene glycol-polypropylene glycol mono (meth) acrylate, poly (ethylene glycol-tetramethylene glycol) B) Mono (meth) acrylate, poly (propylene glycol tetramethylene glycol) mono (meth) acrylate, methoxy polyethylene glycol mono (meth) acrylate, octoxy polyethylene glycol-polypropylene glycol mono (meth) acrylate, lauroxy polyethylene glycol mono Examples include (meth) acrylates, stearoxy polyethylene glycol mono (meth) acrylates, nonyl phenoxy polyethylene glycol mono (meth) acrylates, nonyl phenoxy polypropylene glycol polyethylene glycol mono (meth) acrylates, and the like.

Examples of di (meth) acrylates include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) Acrylate, polyethylene glycol-polypropylene glycol di (meth) acrylate, poly (ethylene glycol-tetramethylene glycol) di (meth) acrylate, poly (pro) Polyethylene glycol di (meth) acrylate, octoxy polyethylene glycol-polypropylene glycol di (meth) acrylate, lauroxy polyethylene glycol di (meth) acrylate, stearoxy polyethylene glycol di (Meth) acrylate, nonyl phenoxy polyethylene glycol di (meth) acrylate, nonyl phenoxy polypropylene glycol polyethylene glycol di (meth) acrylate, reaction of two molecules of (meth) acrylic acid with one molecule of 1, 6-hexanediol diglycidyl Products (eg Nagase Chemtech Inc. "DA-212"), 2 molecules of epoxy (meth) acrylic acid and 1 molecule of neopentyl glycol Reaction product with glycidyl, reaction product with 2 molecules of (meth) acrylic acid and 1 molecule of bisphenol A diglycidyl (eg Nagase ChemteX “DA-250”), 2 molecules of (meth) acrylic acid A reaction product of a propylene oxide adduct of bisphenol A with a diglycidyl derivative, a reaction product of two molecules of (meth) acrylic acid and one molecule of diglycidyl phthalate (eg, “DA-721” manufactured by Nagase ChemteX Co., Ltd.) Reaction product of 2 molecules of (meth) acrylic acid and 1 molecule of polyethylene glycol diglycidyl (eg Nagase ChemteX “DM-811”, “DM-832”, “DM-851”), 2 molecules (Meth) acrylic acid and polyol diglycol such as reaction product of (meth) acrylic acid and one molecule of polypropylene glycol diglycidyl Examples thereof include reaction products with sidyl, and adducts of glycidyl (meth) acrylate and (meth) acrylic acid.

As tri (meth) acrylate, for example, trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, Alkylene oxide-modified trimethylolpropane tri (meth) acrylates (such as Lafomer (registered trademark) PO33F manufactured by BASF) such as ethylene oxide (6 mol) modified trimethylolpropane tri (meth) acrylate (Lasomer (registered trademark) LR8863 manufactured by BASF) Can be mentioned.

Examples of tetra (meth) acrylates include alkylene oxide-modified pentaerythritol tetra (meth) acrylates such as pentaerythritol tetra (meth) acrylate, ethylene oxide (4 moles) -modified pentaerythritol tetra (meth) acrylate (Diseyl Cytec Co., Ebecryl 40), etc. And the like.

Examples of penta (meth) acrylates include dipentaerythritol penta (meth) acrylate and the like.

Examples of hexa (meth) acrylates include dipentaerythritol hexa (meth) acrylate and the like.

Known (meth) acrylate compounds of polymers can be used. Examples of (meth) acrylate compounds of polymers include poly (meth) acrylates such as di (meth) acrylate, tri (meth) acrylate and tetra (meth) acrylate in addition to mono (meth) acrylate.

Among these radically polymerizable compounds, poly (meth) acrylates such as tri (meth) acrylate, tetra (meth) acrylate, penta (meth) acrylate and hexa (meth) acrylate are preferable from the viewpoint of the hardness of the obtained coating film .

Among these radically polymerizable compounds, from the viewpoint of adhesion of the resulting coating film, alkylene oxide-modified pentaerythritol tetra (meth) acrylate, alkylene oxide-modified trimethylolpropane tri (meth) acrylate, alkylene oxide-modified ethylene glycol di ( Meta) acrylate is preferred. From the viewpoint of coexistence of adhesion and hardness, alkylene oxide-modified pentaerythritol tetra (meth) acrylate is more preferable, and ethylene oxide-modified pentaerythritol tetra (meth) acrylate is particularly preferable because of easy availability.

When it is reacted as a mixture of primary hydroxyl group-containing (meth) acrylate (d) and (meth) acrylate inert to isocyanato group to obtain polyurethane resin (A), the isocyanate group contained in the reaction system is The inactive (meth) acrylate can constitute the compound (B) having a polymerizable unsaturated bond.

The total amount of the primary hydroxyl group-containing (meth) acrylate (d) of the polyurethane resin (A) having a polymerizable unsaturated bond and the compound (B) having a polymerizable unsaturated bond is 60 to 80 of the total resin solid content It is weight%. If it is less than 60% by weight, the hardness of the coating film prepared using the aqueous polyurethane resin dispersion may decrease, and if it is more than 85% by weight, the storage stability of the aqueous polyurethane resin dispersion may decrease. . The total amount is more preferably 60 to 80% by weight, still more preferably 65 to 75% by weight.

When the total amount of the primary hydroxyl group-containing (meth) acrylate (d) and the compound (B) having a polymerizable unsaturated bond is 100% by weight, the compound (B) having a polymerizable unsaturated bond is It is preferably 30 to 50% by weight. Within this range, a film produced using the aqueous polyurethane resin dispersion has good adhesion to the PMMA resin and a high hardness can be easily obtained, and also the storage stability of the aqueous polyurethane resin dispersion It is good.

In the aqueous polyurethane resin dispersion of the present invention, a polyurethane resin (A) and a compound (B) having a polymerizable unsaturated bond are dispersed in an aqueous medium. Examples of the aqueous medium include water, a mixed medium of water and a hydrophilic organic solvent, and the like.

Examples of water include, for example, fresh water, ion-exchanged water, distilled water, ultrapure water and the like. Among them, it is preferable to use ion-exchanged water in consideration of ease of obtaining and instability of particles due to the influence of salt and the like.

Examples of hydrophilic organic solvents include lower monohydric alcohols such as methanol, ethanol and propanol; polyhydric alcohols such as ethylene glycol and glycerol; N-methylmorpholine, dimethylsulfoxide, dimethylformamide, N-methylpyrrolidone and the like Aprotic hydrophilic organic solvents and the like can be mentioned. The amount of the hydrophilic organic solvent in the aqueous medium is preferably 0 to 20% by weight.

In the present invention, the acid value of the aqueous polyurethane resin dispersion is preferably 10 to 80 mg KOH / g. Within this range, it is easy to ensure good dispersibility in an aqueous medium and water resistance of the coating film. Specifically, the acid value can be derived by the following formula (3).
[Acid value of aqueous polyurethane resin composition] = [mole number of acidic group of acidic group-containing polyol (b)] × 56.11 / [polyurethane resin (A) and compound (B) having a polymerizable unsaturated bond Total weight] (3)
The acid value is more preferably 12 to 70 mg KOH / g, still more preferably 14 to 60 mg KOH / g.

In the present invention, when the solid content of the polyurethane resin aqueous dispersion is 100 parts by weight, the ratio of the polyol (a) is 2 to 50 parts by weight, and the ratio of the acidic group-containing polyol (b) is 1 to 15 parts by weight It is preferred to prepare the polyurethane resin (A) in such an amount that

When the proportion of the polyol (a) is in the above range, the dispersibility of the polyurethane resin (A) in the aqueous medium is good, and a good film forming property can be obtained for the aqueous polyurethane resin dispersion, and an acidic group When the proportion of the contained polyol (b) is in the above range, the water resistance of the coating film is good, and the dispersibility of the polyurethane resin (A) in the aqueous medium can also be good.
The proportion of the polyol (a) is more preferably 3 to 40 parts by weight, particularly preferably 5 to 30 parts by weight, and the proportion of the acidic group-containing polyol (b) is more preferably 2 to 10 parts by weight, particularly preferably Is 3 to 7 parts by weight.

<Method of producing aqueous polyurethane resin dispersion>
Next, the method for producing the aqueous polyurethane resin dispersion will be described.
The method for producing an aqueous polyurethane resin dispersion of the present invention comprises at least a polyol (a), an acidic group-containing polyol (b), a polyisocyanate (c) and a primary hydroxyl group-containing (meth) acrylate (d) A step (α) of reacting to obtain a polyurethane resin (A);
Neutralizing the acid group of the polyurethane resin (A) (β);
Dispersing the polyurethane resin (A) and the compound (B) having a polymerizable unsaturated bond in an aqueous medium (γ);
Can be included.

The step (α) for obtaining the polyurethane resin (A) is preferably carried out in the presence of oxygen in order to avoid unnecessary consumption of the polymerizable unsaturated bond. Moreover, it is desirable to add a polymerization inhibitor into the reaction system as needed.

The temperature of the step (α) for obtaining the polyurethane resin (A) can be performed at 0 to 120 ° C. in order to avoid unnecessary polymerization of the polymerizable unsaturated bond. Preferably, it is 0 to 100 ° C.

As an acidic group neutralizing agent which can be used in the step (β) of neutralizing the acidic group of the polyurethane resin (A), trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine, N-methyldiethanolamine, N-phenyl Organic amines such as diethanolamine, dimethylethanolamine, diethylethanolamine, N-methylmorpholine, and pyridine; inorganic alkalis such as sodium hydroxide and potassium hydroxide; and ammonia. Among them, preferably organic amines can be used, more preferably tertiary amines can be used, and most preferably triethylamine can be used. Here, the acidic group of a polyurethane resin (A) means a carboxyl group, a sulfonic acid group, a phosphoric acid group, phenolic hydroxyl group etc.

The amount of the acidic group neutralizing agent used is preferably such that the number of moles is from 0.8 to 1.5 with respect to the acidic group of the polyurethane resin (A). Within this range, the dispersibility of the polyurethane resin (A) in water may be reduced, and the storage stability of the aqueous polyurethane resin water dispersion may be easily prevented from being reduced. A situation where the odor of the water dispersion becomes strong can be easily avoided.

In the step (γ) of dispersing the polyurethane resin (A) and the compound (B) having a polymerizable unsaturated bond in the aqueous medium, if (A) and (B) can be dispersed in the aqueous medium There is no particular limitation on the method, the operation order, and the like. For example, a method of mixing (B) in (A) and dispersing in an aqueous medium, a method of mixing (A) in (B) and dispersing in an aqueous medium, or (A) in an aqueous medium A method of mixing and dispersing (B) after dispersion, a method of mixing and dispersing (A) after dispersing (B) in an aqueous medium, or each of (A) and (B) in an aqueous medium A method of mixing after dispersion, a method of mixing (A) and (B) at the time of production, and dispersing in an aqueous medium may be mentioned.

When primary hydroxyl group-containing (meth) acrylate (d) is reacted as a mixture with (meth) acrylate which is inactive to isocyanato group in the production of polyurethane resin (A), (meth) inert to isocyanate group (meth) The acrylate together with the polyurethane resin (A) is contained in the reaction product of step (α), is subjected to step (β) and step (γ), and is polymerizable unsaturated in the final aqueous polyurethane resin dispersion. It will constitute a compound (B) having a bond. In this case, an acid group neutralizing agent can be added to the reaction product of step (α), and the compound can be dispersed in the aqueous dispersion medium together with the compound (B) having a further polymerizable unsaturated bond. Before adding the compound (B) having a further polymerizable unsaturated bond, an aqueous medium may optionally be added.

A known stirring device such as a homomixer or a homogenizer can be used for the mixing, stirring, and dispersion. To the polyurethane resin (A) and the compound (B) having a polymerizable unsaturated bond, add a hydrophilic organic solvent, water, etc. before mixing to improve viscosity adjustment, workability and dispersibility. You can also leave it.

The step (γ) of mixing the polyurethane resin (A) and the compound (B) having a polymerizable unsaturated bond is preferably performed in the presence of oxygen in order to avoid unnecessary consumption of the polymerizable unsaturated bond. Moreover, you may add a polymerization inhibitor as needed. The temperature for mixing the polyurethane resin (A) and the compound (B) having a polymerizable unsaturated bond is preferably 0 to 100 ° C. to avoid unnecessary consumption of the polymerizable unsaturated bond, It is more preferable to carry out at 0 to 90 ° C., more preferably at 0 to 80 ° C., and particularly preferably at 50 to 70 ° C.

In the production method of the present invention, the step (β) of neutralizing the acidic group of the polyurethane resin (A), and the polyurethane resin (A) and the compound (B) having a polymerizable unsaturated bond are dispersed in an aqueous medium. The step (γ) may be carried out first or simultaneously. In this case, (A), (B), the aqueous medium and the acidic group neutralizing agent may be mixed at one time, or the acidic group neutralizing agent is previously mixed in the aqueous medium or (B), And (A) may be mixed.

The proportion of the polyurethane resin (A) in the aqueous polyurethane resin dispersion is preferably 5 to 60% by weight, more preferably 15 to 50% by weight, and still more preferably 25 to 40% by weight. The number average molecular weight is preferably 1,000 to 1,000,000.

In the aqueous polyurethane resin dispersion of the present invention, if necessary, a thickener, a photosensitizer, a curing catalyst, an ultraviolet light absorber, a light stabilizer, an antifoamer, a plasticizer, a surface conditioner, an antisettling agent Additives can also be added. The additives may be used alone or in combination of two or more. The aqueous polyurethane resin dispersion of the present invention is preferably substantially free of a protective colloid, an emulsifier and a surfactant from the viewpoint of the hardness and chemical resistance of the resulting coating film.

<Photocurable composition>
The present invention also relates to a photocurable composition comprising the above aqueous polyurethane resin dispersion and a photopolymerization initiator. As the photopolymerization initiator, known ones can be used, for example, a photocleavable initiator capable of being easily cleaved by ultraviolet irradiation to form two radicals, a hydrogen abstraction initiator be able to. You may use these together. These compounds include, for example, acetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, benzophenone, 2-chlorobenzophenone, p, p'-bisdiethylaminobenzophenone, benzoin ethyl ether, benzoin n-propyl ether, Benzoin isopropyl ether, benzoin isobutyl ether, benzoin n-butyl ether, benzoin dimethyl ketal, thioxanthone, p-isopropyl-α-hydroxyisobutylphenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl -1- [4- (Methylthio) phenyl] -2-morpholinopropan-1-one, 2-hydroxy-2-methyl-1-phenylpro Down-1-one, 2,4,6, - trimethyl benzophenone, 4-methylbenzophenone, 2,2-dimethoxy-1,2-diphenyl-ethanone, and the like. Preferably, hydroxycyclohexyl phenyl ketone is mentioned.

When adding a photoinitiator, it is preferable to add after the process ((gamma)) to which a polyurethane resin (A) and the compound (B) which has a polymerizable unsaturated bond are disperse | distributed in an aqueous medium. The amount of the photopolymerization initiator is preferably 0.5 to 5% by weight based on the total solid content of the aqueous polyurethane resin dispersion (including the compound (B) having a polymerizable unsaturated bond).

<Coating composition and coating composition>
The present invention also relates to a coating composition and a coating composition containing the above aqueous polyurethane resin dispersion.
Other resins can also be added to the coating composition and the coating agent composition of the present invention in addition to the above aqueous polyurethane resin dispersion. Other resins include polyester resins, acrylic resins, polyether resins, polycarbonate resins, polyurethane resins, epoxy resins, alkyd resins, polyolefin resins and the like. These may be used alone or in combination of two or more. Other resins preferably have one or more hydrophilic groups. Examples of the hydrophilic group include a hydroxyl group, a carboxy group, a sulfonic acid group, a polyethylene glycol group and the like.

The other resin is preferably at least one selected from the group consisting of polyester resin, acrylic resin, and polyolefin resin.

The polyester resin can be usually produced by an esterification reaction or transesterification reaction of an acid component and an alcohol component. As the acid component, compounds which are usually used as an acid component in the production of polyester resins can be used. As an acid component, an aliphatic polybasic acid, an alicyclic polybasic acid, an aromatic polybasic acid etc. can be used, for example.
The hydroxyl value of the polyester resin is preferably about 10 to 300 mg KOH / g, more preferably about 50 to 250 mg KOH / g, and still more preferably about 80 to 180 mg KOH / g. The acid value of the polyester resin is preferably about 1 to 200 mg KOH / g, more preferably about 15 to 100 mg KOH / g, and still more preferably about 25 to 60 mg KOH / g.
The weight average molecular weight of the polyester resin is preferably 500 to 500,000, more preferably 1,000 to 300,000, and still more preferably 1,500 to 200,000.

As an acrylic resin, a hydroxyl group-containing acrylic resin is preferable. The hydroxyl group-containing acrylic resin comprises, for example, a solution polymerization method in an organic solvent, a hydroxyl group-containing polymerizable unsaturated monomer and another polymerizable unsaturated monomer copolymerizable with the hydroxyl group-containing polymerizable unsaturated monomer, in water It can manufacture by copolymerizing by well-known methods, such as the emulsion polymerization method of this.
The hydroxyl group-containing polymerizable unsaturated monomer is a compound having one or more hydroxyl group and one or more polymerizable unsaturated bond in one molecule. For example, (meth) acrylic acid such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and the like, and having 2 to 8 carbon atoms Monoesters with dihydric alcohols; ε-caprolactone modified products of these monoesters; N-hydroxymethyl (meth) acrylamide; allyl alcohol; (meth) acrylate having a polyoxyethylene chain whose molecular terminal is a hydroxyl group Etc. can be mentioned.

The hydroxyl group-containing acrylic resin preferably has an anionic functional group. The hydroxyl group-containing acrylic resin having an anionic functional group may be, for example, a polymerizable unsaturated monomer having an anionic functional group such as a carboxylic acid group, a sulfonic acid group or a phosphoric acid group as one of the polymerizable unsaturated monomers. It can be manufactured by using.
The hydroxyl value of the hydroxyl group-containing acrylic resin is preferably about 1 to 200 mg KOH / g, more preferably about 2 to 100 mg KOH / g, and more preferably 3 to 60 mg KOH, from the viewpoint of storage stability of the composition and water resistance of the obtained coating film. It is more preferable that it is about / g.
When the hydroxyl group-containing acrylic resin has an acid group such as a carboxyl group, the acid value of the hydroxyl group-containing acrylic resin is preferably about 1 to 200 mg KOH / g, from the viewpoint of water resistance and the like of the coating film obtained. About 150 mg KOH / g is more preferable, and about 5 to 100 mg KOH / g is more preferable.
The weight average molecular weight of the hydroxyl group-containing acrylic resin is preferably 1,000 to 200,000, more preferably 2,000 to 100,000, and still more preferably 3,000 to 50,000. is there.

Examples of the polyether resin include polymers or copolymers having an ether bond, and examples thereof include polyoxyethylene polyether, polyoxypropylene polyether, polyoxybutylene polyether, bisphenol A, bisphenol F and the like. And polyethers derived from group polyhydroxy compounds.

As polycarbonate resin, the polymer manufactured from the bisphenol compound is mentioned, For example, bisphenol A polycarbonate etc. are mentioned.

As a polyurethane resin, resin which has a urethane bond obtained by reaction of various polyol components, such as an acryl, polyester, a polyether, and a polycarbonate, and polyisocyanate is mentioned.

As an epoxy resin, the resin etc. which are obtained by reaction of a bisphenol compound and epichlorohydrin are mentioned. Examples of bisphenols include bisphenol A and bisphenol F.

Examples of alkyd resins include polybasic acids such as phthalic acid, terephthalic acid and succinic acid and polyhydric alcohols, as well as oils and fats and oils, fatty acids (soybean oil, linseed oil, coconut oil, stearic acid, etc.), natural resins (rosin, succinic acid) Alkyd resins obtained by reacting modifiers such as e.g.

As a polyolefin resin, a polyolefin resin obtained by polymerizing or copolymerizing an olefin monomer with another monomer appropriately according to a general polymerization method is dispersed in water using an emulsifying agent, or an olefin monomer is suitably used with another monomer And resins obtained by emulsion polymerization. Moreover, you may use what is called chlorinated polyolefin modified resin in which the said polyolefin resin was chlorinated depending on the case.
Examples of olefin monomers include ethylene, propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-hexene, 1- Α-olefins such as decene and 1-dodecene; conjugated dienes and non-conjugated dienes such as butadiene, ethylidene norbornene, dicyclopentadiene, 1,5-hexadiene, and styrenes, etc., and these monomers may be used alone. You may use together and may use multiple types.
Examples of other monomers copolymerizable with olefin monomers include vinyl acetate, vinyl alcohol, maleic acid, citraconic acid, itaconic acid, maleic anhydride, citraconic anhydride, itaconic anhydride, etc., and these monomers May be used alone or in combination of two or more.

The coating composition and the coating composition of the present invention can contain a curing agent, whereby the coating or multilayer coating obtained using the coating composition or the coating composition, the water resistance of the coating film Etc. can be improved.

As the curing agent, for example, amino resin, polyisocyanate, blocked polyisocyanate, melamine resin, carbodiimide and the like can be used. The curing agent may be used alone or in combination of two or more.

The amino resin includes, for example, partially or completely methylated amino resin obtained by the reaction of an amino component and an aldehyde component. Examples of the amino component include melamine, urea, benzoguanamine, acetoguanamine, steroguanamine, spiloganamine, dicyandiamide and the like. Examples of the aldehyde component include formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and the like.

Examples of the polyisocyanate include compounds having two or more isocyanato groups in one molecule, and examples thereof include hexamethylene diisocyanate and trimethylhexamethylene diisocyanate.

Examples of blocked polyisocyanates include those obtained by adding a blocking agent to the polyisocyanate group of the aforementioned polyisocyanate, and examples of blocking agents include phenols such as phenol and cresol, methanol, ethanol and the like Fatty alcohols, active methylenes such as dimethyl malonate and acetylacetone, mercaptans such as butyl mercaptan and dodecyl mercaptan, acid amides such as acetanilide and acetic acid amide, lactams such as ε-caprolactam and δ-valerolactam, Blocking agents such as acid imides such as succinimide and maleimide, oximes such as acetoaldoxime, acetone oxime and methyl ethyl ketoxime, and amines such as diphenylaniline, aniline and ethyleneimine Be

Examples of melamine resins include methylolmelamines such as dimethylolmelamine and trimethylolmelamine; alkyl ethers or condensates of these methylolmelamines; and condensates of alkylolates of methylolmelamine.

A color pigment, an extender pigment and a bright pigment can be added to the coating composition and the coating agent composition of the present invention.
Examples of color pigments include titanium oxide, zinc flower, carbon black, molybdenum red, Prussian blue, cobalt blue, azo pigments, phthalocyanine pigments, quinacridone pigments, isoindoline pigments, graphene pigments, perylene pigments and the like. These may be used alone or in combination of two or more. In particular, it is preferable to use titanium oxide and / or carbon black as a color pigment.
Examples of the extender pigment include clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, alumina white and the like. These may be used alone or in combination of two or more. In particular, it is preferable to use barium sulfate and / or talc as an extender pigment, and it is more preferable to use barium sulfate.
As the bright pigment, for example, aluminum, copper, zinc, brass, nickel, aluminum oxide, mica, aluminum oxide coated with titanium oxide or iron oxide, mica coated with titanium oxide or iron oxide, etc. may be used. it can.

The coating composition and the coating agent composition of the present invention may optionally contain a thickener, a curing catalyst, an ultraviolet light absorber, a light stabilizer, an antifoamer, a plasticizer, a surface conditioner, an antisettling agent, etc. Conventional paint additives can be included. These may be used alone or in combination of two or more.

The method for producing the coating composition and the coating agent composition of the present invention is not particularly limited, but any known production method can be used. In general, the coating composition and the coating composition are produced by mixing the above-mentioned aqueous polyurethane resin dispersion and the various additives described above, adding an aqueous medium, and adjusting the viscosity according to the coating method. Ru.

As a to-be-coated material of a coating composition or to-be-coated material of a coating agent composition, a metal, a plastics, an inorganic substance, a wood etc. are mentioned.
The coating composition and the coating agent composition of the present invention have high adhesion to plastics, and in particular, high adhesion to poly (meth) acrylic resins and ABS resins. For this reason, as a to-be-coated material and to-be-coated material, poly (meth) acrylic acid ester resin and / or ABS resin are preferable.

Examples of the coating method of the coating composition or the coating method of the coating agent composition include bell coating, spray coating, roll coating, shower coating, dip coating and the like.

The coating composition and the coating composition of the present invention are applied or cured, and then at least a part of the aqueous medium is evaporated under heating or non-heating, and then cured by irradiation with active energy rays. Is preferred. As active energy rays, ultraviolet rays are preferred.

As a light source of ultraviolet light, xenon lamp, low pressure mercury lamp, high pressure mercury lamp, ultra high pressure mercury lamp, metal halide lamp, carbon arc lamp, tungsten lamp and the like can be used. The irradiation time can be appropriately changed according to the conditions such as the type of the compound having a polymerizable unsaturated bond, the type of the photopolymerization initiator, the thickness of the coating film, the ultraviolet light source and the like. It is preferable to irradiate for 1 to 60 seconds from the viewpoint of workability. Furthermore, in order to complete the curing reaction, it can also be subjected to heat treatment after ultraviolet irradiation.

The irradiation dose of ultraviolet light used when curing the composition of the present invention is preferably 300 to 3,000 mJ / cm ² from the viewpoint of quick curing and workability.

An electron beam etc. can also be used as an active energy ray. In the case of curing by electron beam, a photopolymerization initiator may not be added, and it is preferable to use an electron beam accelerator having an energy of 100 to 500 eV.

The thickness of the coating after curing is not particularly limited, but a thickness of 1 to 100 μm is preferable. More preferably, it is preferable to form a coating having a thickness of 3 to 50 μm.

Next, the present invention will be described in more detail by way of examples and comparative examples, but the present invention is not limited thereto.

Example 1
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. Of the reaction mixture, 55.7 g is withdrawn, cooled to 70 ° C., a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 41 mg KOH / g, 5.4 g), and triethylamine (2. 9 g) was added and mixed. The reaction mixture was cooled to 45 ° C. and water (96.3 g) was added slowly while stirring to obtain an aqueous polyurethane resin dispersion.

Example 2
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. Of the reaction mixture, 57.9 g is withdrawn, cooled to 70 ° C., a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 41 mg KOH / g, 12.9 g), and triethylamine (2. 8 g) was added and mixed. The reaction mixture was cooled to 45 ° C. and water (136 g) was slowly added while stirring to obtain an aqueous polyurethane resin dispersion.

[Example 3]
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. Of the reaction mixture, 57.9 g was withdrawn, cooled to 70 ° C., and pentaerythritol tetraacrylate (PETA (4), 12.0 g) and triethylamine (2.7 g) were added and mixed. The reaction mixture was cooled to 45 ° C. and water (130 g) was added slowly while stirring to obtain an aqueous polyurethane resin dispersion.

Example 4
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. 63.8 g of the reaction mixture was withdrawn, cooled to 70 ° C., and pentaerythritol triacrylate (PETA (3), 13.8 g) and triethylamine (3.2 g) were added and mixed. The reaction mixture was cooled to 45 ° C. and water (147 g) was added slowly while stirring to obtain an aqueous polyurethane resin dispersion.

[Example 5]
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. 45.1 g of the reaction mixture was withdrawn, cooled to 70 ° C., and ditrimethylolpropane tetraacrylate (DTTA, 10.0 g) and triethylamine (2.2 g) were added and mixed. The reaction mixture was cooled to 45 ° C. and water (100 g) was added slowly while stirring to obtain an aqueous polyurethane resin dispersion.

[Example 6]
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol, 89.8 g), obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 31.4 g), isophorone diisocyanate (IPDI) 124 g) were heated in N-ethylpyrrolidone (103 g) in the presence of dibutyltin dilaurate (0.4 g) at 80-90 ° C. for 3 hours under a nitrogen atmosphere. 2,6-Di-tert-butyl-4-methylphenol (0.8 g) and 4-methoxyphenol (0.8 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 397 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.24% by weight. 130 g of the reaction mixture is withdrawn, cooled to 70 ° C., trimethylolpropane triacrylate (TMPTA, 14.0 g), tripropylene glycol diacrylate (TPGDA, 14.0 g), and triethylamine (5.2 g) Added and mixed. The reaction mixture was cooled to 45 ° C. and water (304 g) was added slowly while stirring to obtain an aqueous polyurethane resin dispersion.

[Example 7]
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. 48.3 g of the reaction mixture is withdrawn, cooled to 70 ° C., and ethylene oxide modified pentaerythritol pentaacrylate (EOPETA, tetraacrylate derived from alcohol in which 4 moles of ethylene oxide is added to 1 mole of pentaerythritol, 10.8 g) And triethylamine (2.3 g) were added and mixed. The reaction mixture was cooled to 45 ° C. and water (107 g) was slowly added while stirring to obtain an aqueous polyurethane resin dispersion.

[Example 8]
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. Of the reaction mixture, 32.4 g was withdrawn, cooled to 70 ° C., and polyethylene glycol diacrylate (PEGDA, number average molecular weight 400, 7.0 g of polyethylene glycol moiety) and triethylamine (1.7 g) were added and mixed. . The reaction mixture was cooled to 45 ° C. and water (75.5 g) was added slowly while stirring to obtain an aqueous polyurethane resin dispersion.

[Example 9]
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of pentaerythritol tetraacrylate and pentaerythritol triacrylate (PETA, hydroxyl value 188 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. Of the reaction mixture, 55.7 g is withdrawn, cooled to 70 ° C., a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 41 mg KOH / g, 5.4 g), and triethylamine (2. 9 g) was added and mixed. The reaction mixture was cooled to 45 ° C. and water (96.3 g) was added slowly while stirring to obtain an aqueous polyurethane resin dispersion.

Comparative Example 1
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 95 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. 60.4 g of the reaction mixture was withdrawn, cooled to 70 ° C., and triethylamine (2.9 g) was added and mixed. The reaction mixture was cooled to 45 ° C. and water (111 g) was slowly added while stirring to obtain an aqueous polyurethane resin dispersion.

Comparative Example 2
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (89.9 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 31.3 g), isophorone diisocyanate (IPDI) 124 g) were heated in N-ethylpyrrolidone (101 g) in the presence of dibutyltin dilaurate (0.3 g) under nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.8 g) and 4-methoxyphenol (0.8 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 58 mg KOH / g, 399 g) was added and heated at 90 ° C. for 7 hours. The NCO group content was measured to be 1.89% by weight, and 21% of NCO groups remained.

Comparative Example 3
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol, 24.1 g) obtained by reacting a polyol mixture with carbonate ester in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 8.4 g), isophorone diisocyanate (IPDI) , 33.6 g) were heated in N-ethylpyrrolidone (25.1 g) in the presence of dibutyltin dilaurate (0.1 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.2 g) and 4-methoxyphenol (0.2 g) were added, and the atmosphere was changed to air. Further, a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (DPHA, hydroxyl value 58 mg KOH / g, 169 g) was added and heated at 90 ° C. for 7 hours. The NCO group content was measured to be 0.21% by weight. 60.4 g of the reaction mixture was withdrawn, cooled to 70 ° C., and triethylamine (1.8 g) was added and mixed. The reaction mixture was cooled to 45 ° C. and water (119 g) was slowly added while stirring to obtain an aqueous polyurethane resin dispersion.

Comparative Example 4
A reactor equipped with a stirrer and a heater, ETERNACOLL® PH 100 (manufactured by Ube Industries, Ltd .; number average molecular weight 1054; hydroxyl value 106 mg KOH / g; polyol component 1,5-pentanediol: 1,6-hexanediol = Polycarbonate diol (41.0 g) obtained by reacting a mixture of polyols and carbonate in a molar ratio of 1: 1, 2,2-dimethylol propionic acid (DMPA, 14.4 g), isophorone diisocyanate (IPDI) 56.7 g) were heated in N-ethylpyrrolidone (45.9 g) in the presence of dibutyltin dilaurate (0.2 g) under a nitrogen atmosphere at 80-90 ° C. for 3 hours. 2,6-Di-tert-butyl-4-methylphenol (0.4 g) and 4-methoxyphenol (0.4 g) were added, and the atmosphere was changed to air. Further, a mixture of pentaerythritol tetraacrylate and pentaerythritol triacrylate (DPHA, hydroxyl value: 188 mg KOH / g, 181 g) was added and heated at 90 ° C. for 7 hours. The NCO group content at the end of the urethanization reaction was 0.23% by weight. 60.4 g of the reaction mixture was withdrawn, cooled to 70 ° C., and triethylamine (2.9 g) was added and mixed. The reaction mixture was cooled to 45 ° C. and water (111 g) was slowly added while stirring to obtain an aqueous polyurethane resin dispersion.

[Sample preparation of pencil hardness and adhesion]
3% by weight / solid content of a polymerization initiator (IRGACURE 500, manufactured by Ciba Specialty Chemicals) is added to each of the aqueous polyurethane resin dispersions of Examples 1 to 9 and Comparative Examples 1 to 4, and the coating agent is well stirred. I got This was uniformly applied on ABS resin and PMMA resin so that the film thickness after drying was about 20 μm. Subsequently, the coating film (before ultraviolet irradiation) was obtained by drying at 60 degreeC for 30 minutes. The obtained coating film was passed under a high pressure mercury lamp (single irradiation, ultraviolet irradiation amount 1000 mJ / cm ² ). The obtained polyurethane resin coating film was subjected to pencil hardness measurement and adhesion evaluation.

(Evaluation of hardness)
It evaluated by measuring the pencil hardness of a polyurethane resin coating film.
[Measurement of pencil hardness]
In the polyurethane resin coating on the PMMA resin obtained above, the pencil hardness of the resin coating was measured by a method according to JIS K 5600-5-4.

(Evaluation of adhesion)
The polyurethane resin coating film of the ABS resin and PMMA resin obtained above was evaluated by the cross-cut peeling method. That is, 25 square grids of 4 mm ² were prepared on a test piece with a cutter, and peelability was examined using a cellophane tape.

(Evaluation of storage stability)
The appearance of each of the aqueous polyurethane resin dispersions of Examples 1 to 9 and Comparative Examples 1 to 4 was observed 3 days after production to confirm the storage stability. Evaluation criteria are as follows.
○: no aggregates are observed
X: Aggregates are observed.

The parts by weight in the table represent the parts by weight of each compound when the total solid content in the resin is 100 parts by weight.
The pencil hardness in the table, for example, “H” indicates that the pencil of H does not scratch at all. "2H-3H" is a 3H pencil which is scratched or not scratched, and 2H indicates that it is not scratched at all.
The adhesion in the table indicates the result of the peeling test. "25/25" indicates that 25 cells in 25 cells are in close contact with each other after the test.

The aqueous polyurethane resin dispersion of the present invention can be widely used as a raw material for paints and coatings.

Claims (14)

An aqueous polyurethane resin dispersion composition comprising at least a polyurethane resin (A) having a polymerizable unsaturated bond and a compound (B) having a polymerizable unsaturated bond dispersed in an aqueous medium,
The polyurethane resin (A) having a polymerizable unsaturated bond comprises at least a polyol (a), an acidic group-containing polyol (b), a polyisocyanate (c) and a primary hydroxyl group-containing (meth) acrylate (d) It is obtained by reaction,
An aqueous polyurethane resin, characterized in that the total amount of primary hydroxyl group-containing (meth) acrylate (d) and the compound (B) having a polymerizable unsaturated bond is 60 to 80% by weight of the total resin solid content. Dispersion. The aqueous polyurethane resin dispersion according to claim 1, wherein the polyol (a) is a polycarbonate diol. The total amount of the primary hydroxyl group-containing (meth) acrylate (d) and the compound (B) having a polymerizable unsaturated bond is 65 to 75% by weight based on the total resin solid content. Aqueous polyurethane resin dispersion. The aqueous polyurethane resin dispersion according to any one of claims 1 to 3, wherein the compound (B) having a polymerizable unsaturated bond is a compound having three or more (meth) acryloyl groups in one molecule. The compound (B) having a polymerizable unsaturated bond is selected from the group consisting of alkylene oxide-modified pentaerythritol tetra (meth) acrylate, alkylene oxide-modified trimethylolpropane tri (meth) acrylate, and alkylene oxide-modified ethylene glycol di (meth) acrylate The aqueous polyurethane resin dispersion according to any one of claims 1 to 3, which is one or more selected. The aqueous polyurethane resin dispersion according to any one of claims 1 to 5, wherein the compound (B) having a polymerizable unsaturated bond is an alkylene oxide-modified pentaerythritol tetra (meth) acrylate. The primary hydroxyl group-containing (meth) acrylate (d) is subjected to a reaction for obtaining a polyurethane resin (A) as a mixture with a (meth) acrylate inert to isocyanato groups. The aqueous polyurethane resin dispersion according to item 1. Polyurethane resin (A) as a mixture of dipentaerythritol hexa (meth) acrylate having a hydroxyl value of 80 to 120 mg KOH / g or more and dipentaerythritol penta (meth) acrylate in which the primary hydroxyl group-containing (meth) acrylate (d) has a hydroxyl value of 80 to 120 mg KOH / g The aqueous polyurethane resin dispersion according to any one of claims 1 to 7, which is subjected to a reaction for obtaining In order to obtain polyurethane resin (A) as a mixture of primary hydroxyl group-containing (meth) acrylate (d) and pentaerythritol tetra (meth) acrylate having a hydroxyl value of 100 to 280 mg KOH / g and pentaerythritol tri (meth) acrylate The aqueous polyurethane resin dispersion according to any one of claims 1 to 7, which is subjected to the reaction of The photocurable composition according to any one of claims 1 to 9, which contains a photopolymerization initiator. A paint composition comprising the aqueous polyurethane resin dispersion according to any one of claims 1 to 9. The coating composition according to claim 11, which is for (meth) acrylic resin or acrylonitrile-butylene-styrene resin. A coating composition comprising the aqueous polyurethane resin dispersion according to any one of claims 1 to 9. The coating composition according to claim 13, which is for (meth) acrylic resin or acrylonitrile-butylene-styrene resin.