JPH08311151A - Polyurethane resin, colorants and paints - Google Patents

Abstract

(57) [Abstract] [Purpose] Stabilizes the pigment when it is formed into a coating film by eliminating various problems such as lowering of gloss, lowering of sharpness, opacity, lowering of coloring power and color separation. To provide a polyurethane resin that can be dispersed by a method, a colorant containing the resin, and a paint using the resin. [Structure] Polymer diols such as polyesters, polyethers and polycarbonates having active hydrogen at both ends,
It was obtained by reacting an organic diamine with a prepolymer formed by reacting a polymer diol having a functional group that improves the dispersibility of a pigment in the molecule, a low molecular chain extender, and an organic diisocyanate. Polyurethane resin characterized by: Polymer diol such as polyester, polyether, polycarbonate having active hydrogen at both ends,
Polyurethane resin characterized by being obtained by reacting a polymer diol having a functional group that improves the dispersibility of a pigment in the molecule, a low molecular chain extender, and an organic diisocyanate, including these resins Colorants and paints using these resins.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyurethane resin having excellent pigment dispersibility, a coloring agent and a paint using the polyurethane resin, and more specifically, as a paint in the field of artificial leather, synthetic leather and the like. , Other, paint for woodworking,
The present invention relates to a polyurethane resin, a colorant, and a paint which are useful in many fields such as a color filter field because various coating fields such as a coating material for building materials or a coating film formed have good light transmittance.

[0002]

2. Description of the Related Art Conventionally, since pigments generally have poor dispersibility in a medium as they are, they are dispersed in a pigment-dispersing resin when blended in paints, inks or plastics. For example, it is used as a color concentrate or a colorant, but if the dispersibility of the pigment in such a dispersible resin is poor, the pigment will agglomerate and contain pigment particles agglomerated in this way. For a paint prepared using a coloring agent for reducing the gloss of the resulting coating film, deterioration of sharpness, opacity, various problems such as a decrease in coloring power and color separation may occur. With such a colorant, the performance of the pigment cannot be sufficiently exhibited when it is made into a paint.

[0003]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to provide a coating film with various problems such as a decrease in gloss, a decrease in sharpness, an opacity, a decrease in coloring power and color separation. To provide a polyurethane resin capable of stably dispersing a pigment, a colorant containing the resin, and a coating material using the resin.

[0004]

The above object can be achieved by the present invention described below. That is, the present invention, a polymer diol such as polyester having an active hydrogen at both ends, polyether, polycarbonate, etc., a polymer diol having a functional group for improving the dispersibility of the pigment in the molecule, a low molecular chain extender, Polyurethane resin obtained by reacting a prepolymer produced by reacting with an organic diisocyanate and an organic diamine; polymer diol such as polyester, polyether, polycarbonate having active hydrogen at both ends And a polymer diol having a functional group that improves the dispersibility of the pigment in the molecule, a low-molecular chain extender, and an organic diisocyanate are obtained by reaction, and a polyurethane resin, and these resins And a coating material using these resins.

[0005]

[Function] By making the main chain of the polyurethane resin have a pendant with excellent pigment dispersibility, the dispersibility of the pigment in the dispersion medium is improved, and when it is used as a coating film, its gloss decreases Use of a polyurethane resin, a colorant containing the resin, and the resin, in which various problems such as deterioration of properties, opacity, reduction of coloring power and color separation are eliminated, and a pigment can be stably dispersed in a coating medium. We can provide the original paint.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the preferred embodiments. The polyurethane resin of the present invention is a polymer diol (A1) such as polyester, polyether or polycarbonate having active hydrogen at both ends.
And a polymer diol (A2) such as polyester, polyether, polycarbonate or polyacrylic acid having a functional group having active hydrogen at both ends and improving the dispersibility of the pigment in the molecule, in a weight ratio of 0: 100 to. 100: 10
The mixture of the mixed polymer diol and the low molecular chain extender (A3), which are blended so as to be 0, is an organic diisocyanate (B1) and the equivalent ratio of NCO / OH is 1.5 to 2.0. It can be obtained by reacting an organic diamine (C1) with a prepolymer having a terminal NCO obtained by reacting in such a quantitative relationship. The organic diamine (C1) may not be used when the NCO / OH equivalent ratio is about 1: 1.

As the above-mentioned polymer diol (A1),
Examples thereof include polyesters, polyethers, polycarbonates and their derivatives having a number average molecular weight of 500 to 3000 and having active hydrogen at both ends, or mixtures and copolymers thereof.

Further, as the polymer diol (A2) having a functional group for improving the dispersibility of the pigment in the molecule, polyesters, polyethers, polycarbonates having a number average molecular weight of 500 to 3,000 and active hydrogen at both ends, and Polymerization of their derivatives or their mixtures and copolymers, acrylic acid esters (eg, methyl, ethyl, butyl ester, etc.), methacrylic acid esters (eg, ethyl, methyl, butyl ester, etc.) etc. as neutral monomers The resulting polymer having a number average molecular weight of 5,000 to 20,000 and having active hydrogen at both ends has a main chain, and a side chain as a pendant has a phenyl group, a naphthyl group as a functional group for improving the dispersibility of the pigment, An aromatic ring such as an anthryl group is contained in the molecule in a weight ratio of 10 to 90% by weight, preferably 20 to 8%.
One containing 0% by weight is included.

A more specific example of the polymer diol (A2) containing a functional group for improving the dispersibility of the pigment in the molecule will be described in more detail. The polymer diol is represented by the following formula. In the above formula, R _{1 to} R ₃ are hydrogen atoms or alkyl groups, and R ₄ is a phenyl group, naphthyl group or anthryl group. X is a polyester polymer, a polyether polymer, a polycarbonate polymer or an acrylic polymer, and the acrylic polymer has a side chain of an alkyl group such as a methyl group, an alkoxycarbonyl group, an alkylaminoalkyl group, or a quaternary product thereof. And so on. m and n are integers,
The ratio is m: n = 10: 90 to 90:10, and m
+ N is a valence within the above molecular weight range.

When the content of the functional group for improving the dispersibility of the pigment in the molecule in the molecule is less than 10% by weight, the effect of improving the pigment dispersibility of the finally obtained polyurethane resin is small, and 80% by weight. When it exceeds%, the crystallinity of the functional group which improves the dispersibility of the pigment appears in the molecule, and when it is finally made into a paint, the stability as a paint cannot be maintained. It is in the range of 50% by weight.

As the low molecular chain extender (A3) used in the production of the polyurethane resin of the present invention, for example, many diols such as ethylene glycol, butanediol, neopentyl glycol, diethylene glycol and 1,5-pentanediol are used. Is mentioned.

Examples of the organic diisocyanate (B1) used in the production of the polyurethane resin of the present invention include diphenylmethane-4,4-diisocyanate,
Aromatic diisocyanates such as 2,4- or 2,6-tolylene diisocyanate, aliphatic diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, alicyclic diisocyanates such as hydrogenated MDI Nart is mentioned. Among them, isophorone diisocyanate is used as the organic diisocyanate which is reacted with the polymer diol (A1), the polymer diol (A2) containing a functional group for improving the dispersibility of the pigment in the molecule, and the low molecular chain extender (A3). Are preferred because they give the most excellent polyurethane resin with pigment dispersibility.

Examples of the organic diamine (C1) used for increasing the molecular weight of the prepolymer obtained by reacting the above-mentioned diols and diisocyanates in excess of isocyanate include, for example, isophoronediamine and 4,4-diaminodicyclohexane. And alicyclic diamines, straight-chain aliphatic diamines, aromatic diamines and the like.

In the production of the polyurethane resin of the present invention, the catalysts used in the production of ordinary polyurethane are used. Specifically, for example, metal compounds such as dibutyltin dilaurate, zinc octate, tetramethylbutanediamine, etc. And tertiary amines thereof. As the solvent used in the production of the polyurethane resin of the present invention,
For example, N, N-dimethylformamide, toluene, methyl ethyl ketone, tetrahydrofuran, and other solvents that are commonly used in the production of polyurethane resins are used as they are.

The polyurethane resin of the present invention uses the above-mentioned raw materials, and the polymer diol (A1) and the polymer diol (A2) are in a weight ratio of 0: 100 to 100: 100.
The polymer diol and the low molecular chain extender (A3) are mixed with each other by using an organic diisocyanate (B1).
It is obtained by reacting in a quantitative relationship such that the equivalent ratio of CO / OH is 1.5 to 2.0 to give a prepolymer of terminal NCO, and reacting this with an organic diamine (C1). The organic diamine (C1) may not be used when the NCO / OH equivalent ratio is about 1: 1.

The molecular weight of the polyurethane resin of the present invention is usually 50,000 to 300,000, preferably 1
It is from 0,000 to 200,000. When the molecular weight is too low, the effect of dispersing the pigment is insufficient, while when the molecular weight is too high, the dispersibility of the pigment is insufficient. The functional group which improves the dispersibility of the pigment in the resulting polyurethane resin is usually 0.1 to 100 parts by weight of the polyurethane resin.
It is 10% by weight, preferably 1.0 to 5.0% by weight. If it is out of the above range, the dispersibility of the pigment becomes insufficient.

When the polyurethane resin of the present invention obtained as described above is used as a resin for dispersing pigments, various additives used in conventional polyurethane resins such as flame retardants, antioxidants, and ultraviolet rays are used. Absorbents, plasticizers, surfactants and the like can be added. The polyurethane resin is particularly useful as a dispersant for pigments during paint production, and in the production of paints, first, the pigment and the polyurethane resin of the present invention, a solvent, and optionally other dispersants and additives are added. In addition, they are mixed and the pigment is dispersed using a disperser to prepare a colorant, and if necessary, a film-forming resin and a diluent solvent are added thereto to prepare the coating material of the present invention.

Of course, the coating material may be immediately prepared with the necessary components without passing through the coloring agent. As a disperser used to disperse the pigment in the production of the colorant or the paint, a sand grind mill, a ball mill, an attritor mill, or a triple roll mill used in the paint industry or the ink industry can be used, but especially three It is preferable to use a roll mill.

As the pigment used for preparing the coating material, various inorganic pigments or organic pigments which are usually used in the conventional coating industry and ink industry can be used. The organic pigment has a large number of aromatic rings, on the other hand, the polyurethane resin in the present invention also has a large number of aromatic rings as pendants, and the affinity of the two allows the organic pigment to be well dispersed, The present invention is particularly effective for organic pigments.

As the film-forming material for paints, the above-mentioned polyurethane resin of the present invention can be used as it is as a film-forming material, and conventionally known polyurethane-based resins, acrylic resins and the like can also be used as film-forming materials. It can be used as a material or used in combination. In addition, as other dispersants to be used as necessary, various amine-based, polymer copolymers, surfactants, dispersants such as fatty acids, which are commonly used in the paint industry and ink industry, should be used. Can be done.

[0021]

The present invention will be described in more detail with reference to the following examples and comparative examples, but the present invention is not limited thereto. Synthesis Example 1 1,4-adipate (1,4-adipate having an average molecular weight of 2,000)
150 parts of polyester diol consisting of butanediol and adipic acid) (hereinafter referred to as parts by weight), functional group-containing polymer diol (average molecular weight 14000, functional group = phenyl group, weight% of functional group =) which improves the dispersibility of the pigment in the molecule. Two
5%) (hereinafter referred to as a functional group polyol) 112.5 parts and 1,3-butanediol 1.7 parts were mixed with 58.6 parts of isophorone diisocyanate and reacted at 110 ° C. for 5 hours. Then, 201.4 parts of toluene, 201.4 parts of isopropanol, and cyclohexanone 402.7.
Is added, and isophoronediamine 22.
4 parts were gradually added dropwise to give a solid content of 30% and a viscosity of 30 dPa.s.
Polyurethane resin (D1) of the present invention of S (molecular weight of about 10
10,000) was obtained. The amount of the functional group which improves the dispersibility of the pigment in this polyurethane resin was 2.2% by weight.

Synthesis Example 2 150 parts of 1,4-adipate having an average molecular weight of 2,000,
Functional group polyol (average molecular weight 14,000, functional group =
Phenyl group, functional group weight% = 25%) 112.5 parts and a mixture of 7.7 parts of 1,3-butanediol and 96.2 parts of isophorone diisocyanate were added to the mixture at 110 ° C.
After reacting for a period of time, 407.4 parts of toluene and 407.4 parts of isopropanol were added, and 36.8 parts of isophoronediamine were gradually added dropwise with a dropping funnel to obtain a solid content of 30.
%, Viscosity 200 dPa. A polyurethane resin (D2) of the present invention of S (molecular weight of about 100,000) was obtained. The amount of the functional group which improves the dispersibility of the pigment in this polyurethane resin was 1.9% by weight.

Synthesis Example 3 150 parts of 1,4-adipate having an average molecular weight of 1,500,
Functional group polyol (average molecular weight 14,000, functional group =
Phenyl group, functional group weight% = 25%) 112.5 parts,
1,4-Butanediol 18.5 parts, N, N-dimethylformamide 441.2 parts and methyl ethyl ketone 44
To a mixture of 1.2 parts, 97.2 parts of diphenylmethane-4,4-diisocyanate was added and reacted at 80 ° C. for 5 hours to give a solid content of 30% and a viscosity of 500 dPa.s. As a result, a polyurethane resin (D3) of the present invention of s (molecular weight of about 150,000) was obtained. The amount of the functional group that improves the dispersibility of the pigment in this polyurethane resin was 2.0% by weight.

Comparative Synthesis Example 1 33.6 parts of isophorone diisocyanate was added to a mixture of 150 parts of 1,4-adipate having an average molecular weight of 2,000 and 1.7 parts of 1,3-butanediol at 100 ° C. After reacting for 4 hours, 462.2 parts of N, N-dimethylformamide were added, and 12.8 parts of isophoronediamine was gradually added dropwise with a dropping funnel to give a solid content of 30% and a viscosity of 3
0 dPa. A polyurethane resin (E1) (molecular weight of about 100,000) as a comparative example of s was obtained.

Comparative Synthesis Example 2 To 150 parts of 1,4-adipate having an average molecular weight of 2,000 and 4.4 parts of 1,3-butanediol was added 34.3 parts of isophorone diisocyanate, and the mixture was heated at 100 ° C. for 4 hours. After the reaction, N, N-dimethylformamide was added to 470.
Add 9 parts and add isophoronediamine 1 with a dropping funnel.
3.1 parts was gradually added dropwise, solid content 30%, viscosity 200P
a. A polyurethane resin (E2) (molecular weight of about 100,000) as a comparative example of s was obtained.

Comparative Synthesis Example 3 150 parts of 1,4-adipate having an average molecular weight of 1,500,
1,4-Butanediol 18.5 parts, N, N-dimethylformamide 287.0 parts and methyl ethyl ketone 28
To 7.5 parts of the mixture, 77.5 parts of diphenylmethane-4,4-diisocyanate was added and reacted at 80 ° C. for 5 hours to give a solid content of 30% and a viscosity of 500 dPa.s. As a result, a polyurethane resin (E3) (molecular weight of about 150,000) as a comparative example was obtained.

Example 1 Polyurethane resin solution (D1) 25 obtained in Synthesis Example 1
85 parts of cyclohexanone and 15 parts of Seika Fast Yellow 2720 manufactured by Dainichiseika Kogyo Co., Ltd. as a pigment were added and stirred, and then dispersed in 2 passes by a three-roll mill,
After adjusting with a solvent, the paste of the present invention (F
1) was obtained. After dispersing the pigment in this manner, 100 parts of the polyurethane resin (D2) obtained in Synthesis Example 2 and N,
To a mixture of 50 parts of N-dimethylformamide, 15 parts of the above (F1) was added and sufficiently stirred with a disper to obtain a coating material (F2) of the present invention.

Example 2 A mixture of 100 parts of the polyurethane resin (D3) obtained in Synthesis Example 3 and 50 parts of a solvent prepared by mixing 1: 1 N, N-dimethylformamide and methyl ethyl ketone was used. 15 parts of the obtained coloring agent (F1) of the present invention was added and sufficiently stirred with a disper to obtain a coating material (F3) of the present invention.

Comparative Example 1 Polyurethane resin (E2) 10 obtained in Comparative Synthesis Example 2
To a mixture of 0 parts and 50 parts of N, N-dimethylformamide, 15 parts of the above (F1) was added and sufficiently stirred with a disper to obtain a paint (F4) as a comparative example.

Comparative Example 2 Polyurethane resin (E3) 10 obtained in Comparative Synthesis Example 3
15 parts of the above (F1) was added to a mixture of 0 parts and 50 parts of N, N-dimethylformamide / methyl ethyl ketone 1/1 mixed solvent, and the mixture was thoroughly stirred with a disperser to prepare a coating composition of Comparative Example (F5 ) Got.

Comparative Example 3 Polyurethane resin (E1) 25 obtained in Comparative Synthesis Example 1
85 parts of cyclohexanone and 15 parts of Seika Fast Yellow 2720 (Dainichi Seika Kogyo Co., Ltd.) as a pigment are added and stirred, then dispersed in 2 passes with a three-roll mill and adjusted with a solvent, and then a paste-like colorant. (G1) was obtained. After dispersing the pigment in this manner, the above (G) was added to a mixture of 100 parts of the polyurethane resin (D2) obtained in Synthesis Example 2 and 50 parts of N, N-dimethylformamide.
15 parts of 1) was added and sufficiently stirred with a disper to obtain a coating material (G2) of Comparative Example.

Comparative Example 4 100 parts of the polyurethane resin (D3) obtained in Synthesis Example 3 and 50 parts of a solvent prepared by mixing N, N-dimethylformamide and methyl ethyl ketone in a ratio of 1: 1 were colored in Comparative Example 3. 15 parts of the agent (G1) was added and sufficiently stirred with a disper to obtain a paint (G3) as a comparative example.

Comparative Example 5 Polyurethane resin (E2) 10 obtained in Comparative Synthesis Example 2
To a mixture of 0 parts and 50 parts of N, N-dimethylformamide, 15 parts of the colorant (G1) obtained in Comparative Example 3 was added and thoroughly stirred with a disper to obtain a paint (G4) of Comparative Example. It was

Comparative Example 6 Polyurethane resin (E3) 10 obtained in Comparative Synthesis Example 3
15 parts of the colorant (G1) obtained in Comparative Example 3 was added to a mixture of 0 parts and 50 parts of a solvent in which N, N-dimethylformamide and methyl ethyl ketone were mixed in a ratio of 1: 1 and thoroughly stirred with a disper. A coating material (G5) of Comparative Example was obtained.

Each coating material obtained in the above Examples and Comparative Examples was applied onto a polypropylene film with a clearance of 50 μm and dried to obtain each coated product. The results for these coatings are shown in Table 1 below.

Table 1

The evaluation methods of Examples and Comparative Examples are as follows. 1. Coloring power, gloss, transparency and sharpness ⊙; extremely good ∘; good Δ; somewhat good ×; poor Color separation (comparison between paint immediately after stirring and paint left for 15 hours) ○: No color separation ×: Color separation Haze

[0038]

As described above, according to the present invention, the main chain of the polyurethane resin has a pendant having excellent pigment dispersibility, whereby the dispersibility of the pigment in the dispersion medium is improved and the coating is performed. A polyurethane resin capable of stably dispersing a pigment in a coating medium, which eliminates various problems such as a decrease in gloss, a decrease in sharpness, opacity, a decrease in coloring strength and color separation when formed into a film, A colorant containing the resin and a coating material using the resin can be provided.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masayuki Inabe 1-7-6 Nihonbashi-Bakuro-cho, Chuo-ku, Tokyo Dainichi Seika Kogyo Co., Ltd.

Claims (9)

[Claims] 1. A polyester having active hydrogen at both ends,
A polymer diol such as polyether or polycarbonate, a polymer diol having a functional group that improves the dispersibility of the pigment in the molecule, a low molecular chain extender, and a prepolymer formed by reacting with an organic diisocyanate, A polyurethane resin obtained by reacting with an organic diamine. 2. A polyester having active hydrogen at both ends,
Characterized by reacting a polymer diol such as polyether or polycarbonate, a polymer diol having a functional group that improves the dispersibility of the pigment in the molecule, a low molecular chain extender, and an organic diisocyanate And polyurethane resin. 3. A polymer diol having a functional group for improving the dispersibility of a pigment has a main chain of polyester, polyether, polycarbonate, polyacrylic acid or the like having active hydrogen at both ends, and its pendant is a phenyl group or naphthyl. A group having an aromatic ring such as a group or an anthryl group.
The polyurethane resin according to 2 above. 4. A pigment and a dispersant, wherein the dispersant is
Polyester, polyether with active hydrogen at both ends,
A polymer diol such as polycarbonate, a polymer diol having a functional group that improves the dispersibility of the pigment in the molecule, a low molecular chain extender, and a prepolymer formed by reacting with an organic diisocyanate; and an organic diamine. A colorant, which is a polyurethane resin obtained by reacting 5. A pigment and a dispersant, the dispersant comprising:
Polyester, polyether with active hydrogen at both ends,
It is a polyurethane resin obtained by reacting a polymer diol such as polycarbonate, a polymer diol having a functional group that improves the dispersibility of the pigment in the molecule, a low molecular chain extender, and an organic diisocyanate. Characterizing colorant. 6. A polymer diol having a functional group for improving the dispersibility of a pigment has a main chain of polyester, polyether, polycarbonate, polyacrylic acid or the like having active hydrogen at both ends, and its pendant is a phenyl group or naphthyl. 5. An aromatic ring such as a group or an anthryl group.
The coloring agent according to claim 5. 7. A paint containing a pigment and a dispersant in a medium, wherein the dispersant is a polymer diol such as polyester, polyether or polycarbonate having active hydrogen at both ends, and the dispersibility of the pigment in the molecule. That is a polyurethane resin obtained by reacting a prepolymer produced by reacting a polymer diol having a functional group that improves the polymer, a low molecular chain extender, and an organic diisocyanate with an organic diamine. A paint characterized by. 8. A paint containing a pigment and a dispersant in a medium, wherein the dispersant is a polymer diol such as polyester, polyether or polycarbonate having active hydrogen at both ends, and the dispersibility of the pigment in the molecule. A coating material characterized by being a polyurethane resin obtained by reacting a polymer diol having a functional group for improving the property, a low molecular chain extender, and an organic diisocyanate. 9. A polymer diol having a functional group for improving the dispersibility of a pigment has a main chain of polyester, polyether, polycarbonate, polyacrylic acid or the like having active hydrogen at both ends, and a phenyl group or a naphthyl group as a pendant. 7. An aromatic ring such as an anthryl group.
Paint described in.