JPS6270458A - Coating resin composition - Google Patents

Abstract

PURPOSE:To provide a coating resin compsn. having excellent adhesion, printability, etc., by blending a pigment and an org. solvent with a polyurethane resin composed of a reaction product of a high-molecular diol, an org. diisocyanate, a chain extender and a reaction terminator. CONSTITUTION:A high-molecular diol (A) having an MW of 300-3,000 (e.g., polyethylene glycol), an org. diisocyanate (B) (e.g., tolylene diisocyanate) and a chain extender of formula I (wherein R1, R2 are each a 1-5C alkylene; R2 is a 1-5C alkyl; X is OH, NH2) (e.g., methyliminobisethylamine) and/or a reaction terminator of formula II (e.g., dimethylaminoethylamine) (C) are reacted together to produce a polyurethane resin contg. tert-amino groups of formulas III and/or IV. A pigment and an organic medium are blended with a resin component wholly or partially composed of the polyurethane resin to obtain the desired coating resin compsn.

Description

Detailed Description of the Invention <Field of Industrial Application> The present invention relates to a resin composition for coating, and more specifically to a printing ink suitable for printing various plastic films and sheets or for coating the surface of various synthetic resin products. Or, it is intended to provide a coating agent.

<Conventional technology> In recent years, with the diversification of packaging containers and the high-I brittleness of synthetic resin products such as synthetic leather, printing inks and various coating agents used for decoration or surface protection of plastic films, etc. have also become more sophisticated. Increasingly, high performance and quality are required.

In particular, printing ink is used to make packaging containers beautiful,
It has become necessary to respond to higher grade products, adhesion to various composite films, and suitability for various post-processing.

These various suitability are mainly determined by the binder resin used for printing ink, etc., and polyols, polyols,
Organic polyinsyanate A polyurethane resin reacted with a chain extender such as polyamine, if necessary, has been used.

<Problems to be solved by the invention> Printing inks using these polyurethane resins as binders have sufficient adhesion to nylon, polyester films, etc., but they do not adhere well to general-purpose films such as polyethylene and polypropylene films. However, it does not have sufficient adhesion to other materials, and is not suitable for lamination.

In addition, the pigment dispersibility was insufficient, and there were problems in various printing suitability or coating suitability. Conventionally, methods of adding surfactants or other additives have been used to solve problems such as pigment dispersibility, but these additions degrade the physical properties of the film, and are used in food containers, etc. The boilability, retort suitability, etc. were deteriorated.

In addition, hydroxyl groups, aminoalcoholic hydroxyl groups, etc. are introduced at the terminals by combining polyols, organic polyisocyanates, chain extenders, and reaction terminators used in the process of manufacturing polyurethane resins to disperse pigments. Efforts have been made to improve the properties, but the adhesion and lamination suitability have not yet been satisfactory.

In order to solve the problems of conventional polyurethane resins, Nagisa et al. conducted research on Ua = using a specific chain extender and/or reaction terminator. The present invention was completed based on the discovery that the polyurethane resin obtained by the method solves the above-mentioned problems.

That is, the present invention provides a coating resin composition mainly composed of a pigment, a polyurethane resin, and an organic medium,
All or part of the polyurethane resin has a molecule i: 30
0 to 3,000, an organic diisocyanate, a chain extender represented by the following general formula [I], and/or a reaction termination agent represented by the following general formula [H]. It is an object of the present invention to provide a coating resin composition characterized by being a polyurethane resin.

General Formula [I] X-R, -N-R2-X The present invention will be explained in more detail below.

Regarding the manufacturing method of the specific polyurethane resin used in the present invention, a high molecular weight diol component and an organic diisocyanate component are reacted in an excess ratio of the latter to synthesize a prepolymer having an incyanate group at the end, and this is combined with the general formula [■ ] to obtain the desired polyurethane resin, or simultaneously react a high molecular weight diol component, an organic diisocyanate component, and a chain extender represented by the general formula [D] to obtain the desired polyurethane resin. A polyurethane resin can be obtained.

On the other hand, a polymeric diol component, an organic diisocyanate component, and a chain extender (which may be used alone or in combination with the chain extender represented by the general formula "■" and the conventional chain extender described below). React to synthesize a polyurethane resin having an incyanate group at the end, and then
The desired polyurethane resin can also be obtained by stopping the reaction with a specific reaction terminator represented by the general formula rII].

As the components of the polyurethane resin according to the present invention, 6 conventionally known components can be used. Among the high molecular weight diol components, polyether type diols include polyalkylene glycols such as polyethylene glycol and polypropylene glycol, Polyoxyalkylene glycols such as ethylene glycol, polyoxypropylene glycol, polyoxyethylene propylene glycol, polyoxytetramethylene glycol, or fullylene oxide adducts of bisphenol A such as ethylene oxide, propylene oxide, and ethylene propylene oxide. Alternatively, polycabrolactone diol, polycarbonate diol, etc. can be mentioned, and polyester type diols include dibasic acids such as adipic acid, phthalic anhydride, isophthalic acid, maleic acid, fumaric acid, succinic acid, etc. - lengelicol, diethylene glycol, propylene glycol,
1.4 phthanediol, neopentyl glycol, 1.
It is obtained by a condensation reaction with glycols such as 6-hexanediol. However, the molecular weight of these polyether type diols and polyester type diols is 30.
It is necessary that the molecular weight is in the range of 0 to 3,000, preferably 1.000 to 2.000, and if the molecular weight is less than 300, the cohesive force between the resins will be excessive and the polyurethane resin synthesized from it will have poor adhesiveness. It has the disadvantage that it has poor suitability for lamination processing and that a large amount of solvent remains in the printed matter. On the other hand, if the molecular weight is 3,000 or more, the cohesive force between the resins will be insufficient and plopping will easily occur.

In addition, as the organic diisocyanate component, tolylene diisocyanate 11 diphenylmethane diisocyanate,
Xylidine diisocyanate, methylene diisocyanate, inpropylene diisocyanate, hexamethylene diisocyanate, 2.2.4- or 2.4.4-) dimethyl hexamethylene diisocyanate, lysine diisocyanate, 1,4-cyclohexane diisocyanate, inphoron diisocyanate isocyanate), 4,4-dicyclohexylmethane diisocyanate, and the like.

In addition, from the standpoint of obtaining a resin with excellent solubility,
Alicyclic diisocyanates such as inphorone diisocyanate and 4,4-dicyclohexylmethane diisocyanate are preferred.

Specific examples of the chain extender represented by the general formula [D] used in the present invention include diamines such as methyliminobisethylhumine, methyliminobispropylamine, and ethyliminobispropylamine. Examples include diols such as N-methylgetanolamine and N-butylgetanolamine.

Specific examples of the reaction terminator represented by the general formula [■] are:
Dimethylaminoethylamine, dimethyla7a2. . −
7,78 examples. "゛・-7・Here, a chain extender represented by the general formula [0 or [11],
In reaction terminator. A2. Yat, MR,, A7. Yag7 group R
The number of carbon atoms in 1, R2 is preferably in the range of 1 to 5,
If the number of carbon atoms is 6 or more, the strength of the film becomes weak and problems such as propagation are likely to occur, which is not preferable.

Conventional diamines such as ethylene diamine, propylene diamine, hexamethylene diamine, inphorone diamine, dicyclohexylmethane diamine, etc., which can be used in combination with the above-mentioned specific chain extenders and reaction terminators or alone, are -mata, ethylene diamine, etc. Examples include diols such as glyfur, propylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, 14-cyclo-\xyl glycol, and
Examples of conventional reaction terminators include monoamines such as n-butylamine and monoelamine, and monoalcohols such as methanol, ethanol, and propyl alcohol.

In addition, in the polyurethane resin specified in the present invention, the reaction ratio of the specific chain extender and/or reaction terminator is determined by the amount of incyanate groups in the organic diisocyanate component, the hydroxyl group in the high molecular weight diol component, and if necessary in combination. It can be decided to adjust the concentration of amino groups and hydroxyl groups of conventional chain extenders and reaction terminators. -R1N Rz -RI introduced into polyurethane resin
The amount of tertiary amino groups represented by N(R3)2 is the molecular weight of the total polyurethane resin (meaning the sum of the polyurethane resin specified in the present invention and conventional general polyurethane resins used in combination as necessary), 10, 000 hit, o, i
It is necessary that the number is in the range of ~10.

If it is below this range, the pigment dispersibility and suitability for laminating will decrease, and if it is beyond this range, the water resistance etc. of the urethane film will tend to decrease, which is not preferable.

Solvents used in the synthesis of urethane resins include benzine, toluene, and
Aromatic solvents such as xylene; esters such as ethyl acetate, n-propyl acetate, butyl acetate; Examples include ketone solvents such as butyl ketone or a mixture thereof, but from the viewpoint of the working environment, ester solvents or alcohol solvents alone or a mixture thereof are most suitable.

When manufacturing a printing ink or coating agent using a polyurethane resin synthesized using each of the above components, various pigments are added to a solution of the polyurethane resin, kneaded, dispersed I~, as necessary. Probuking prevention + h agent,
It can be produced by using additives such as plasticizers or compatible resins such as nitrified cotton, maleic acid resin, or salt-vinyl acetate copolymer.

<Example> Synthesis Example 1 Into a 11-fourth flask equipped with a stirrer, a thermometer, a Dimroth, N, and a gas inlet tube, a polyx resin with an average molecular weight of 2,000 obtained from adipic acid and 1.4-butanediol was added. f
/L/ 200.0 parts by weight of Shiol, 44.4 parts by weight of Involonshi 7'/7*-), N2
React for several hours while introducing gas. After cooling, 234.0 parts by weight of ethyl acetate was added and dissolved uniformly, 155.0 parts by weight of isopropyl alcohol and 12.3 parts by weight of methyliminohisfurobylamine were added, and further 3.1 parts by weight of dimelaminoprobylamine was added. Stop the reaction by adding parts by weight,
A solution of the desired polyurethane resin was obtained. The resulting resin solution had a solid content of 40% and a viscosity of 30°C/25°C. Synthesis Example 2 (referred to as Resin Solution A) In the same manner as in Synthesis Example 1, a polyurethane resin solution (resin solution B) having the following composition was obtained.

Isophorone diisocyanate 44.4 Methyliminobispropylamine 12.3 Monoethanolamine 1.8 Ethyl acetate
233.0 Isopropyl alcohol 155.0 The obtained resin solution Y3 has a solid content of 40 copies and a viscosity of 25 voids/2.
The temperature was 5°C.

Synthesis Example 3 In the same manner as in Synthesis Example 1, a polyurethane resin solution (resin solution C) having the following composition was obtained.

Polyoxytetramethylene glycol 200.0
1ii part (molecular weight 2000) Inphorone diisocyanate 444 Isophorone diamine 14,5 dimethylaminobutylamine 31 Ethyl acetate
236.0 Isopropyl alcohol 157.0 The obtained resin solution C has a solid content of 40% and a viscosity of 30 voids/
The temperature was 25°C.

Synthesis Example 4 In the same manner as in Synthesis Example 1, a polyurethane resin solution (resin solution D) having the following composition was obtained.

Polyoxytetramethylene glycol 200.0
M11 parts (molecules, t 2000) Isophorone diisocyanate 44.4N
-Methyljetanolamine 5.1 Inphorondiamine 7.2 Monoethanolamine 1.8 Ethyl acetate
233.0 Isopropyl alcohol 155.0 The obtained resin solution has a solid content of 40% and a viscosity of 20 voids/25
It was ℃.

Synthesis Example 5 In the same manner as in Synthesis Example 1, a polyurethane resin solution (resin solution E) having the following composition was obtained.

Polyoxytetramethylene glycol 200.0
Parts by weight (molecules! 2000) Inphorone diisocyanate 44.4 Inphorone diamine 145 Dimethylaminoethanol 2.7 Ethyl acetate
236.0 Isopropyl alcohol 157.0 The obtained resin solution E has a solid content of 40% and a viscosity of 30 poise/2
The temperature was 5°C.

Synthesis Example 6 In the same manner as in Synthesis Example 1, a polyurethane resin solution (resin solution F) having the following composition was obtained.

Polyester diol (same as Synthesis Example 1) 200 parts by weight (molecular weight 2000) Isophorone diisocyanate 44.4
1.6-Hexanediamine 9.
9 Ethylene glycol 1.9 Ethyl acetate 230.4 Isopropyl alcohol 153.6 The obtained resin solution F has a solid content of 40% and a viscosity of 20 voids/
The temperature was 25°C.

Synthesis Example 7 In the same manner as in Synthesis Example 1, a polyurethane resin solution (resin solution G) having the following composition was obtained.

Isophorone diisocyanate 44.4
Inphorondiamine 14.5 Monoethanolamine 1.8 Ethyl acetate 234.6 Isopuvyl alcohol 156.4 The obtained resin solution G has a solid content of 40% and a viscosity of 30 poise/2.
The temperature was 5°C.

Synthesis Example 8 In the same manner as in Synthesis Example 1, a polyurethane resin solution (resin solution H) having the following composition was obtained.

Inphorone diisocyanate 44.4
Inphorondiamine 14.5 Monobutylamine 2.2 Ethyl acetate 238.0 Isopropyl alcohol 158.0 The obtained resin solution H has a solid content of 40% and a viscosity of 30 poise 7
The temperature was 25°C.

Examples 1 to 5 and Comparative Examples 1 to 3 Each polyurethane resin solution A obtained in Synthesis Examples 1 to 8
-H was used as a binder for printing ink, and the performance of each resin was evaluated. Printing inks are mixed and manufactured in-house with the following compositions.

Composition of white ink Polyurethane resin solution 30 parts Isopropyl alcohol 25 parts Titanium oxide
30 parts ethyl acetate 20
Composition of blue ink Polyurethane resin solution 30 parts Isopropyl alcohol 25 parts Shanin Blue
10 parts ethyl acetate 35
The respective printing inks were used to print on various films, and the adhesion, suitability for various prints, suitability for laminating, and suitability for boiling and retorting were evaluated. The results are shown in Table 1.

In addition, each evaluation method is based on the following method.

■) Adhesiveness After printing each test ink on a specified film using a gravure proofing machine and leaving it for one day, stick sellotape on the printed surface and peel it off quickly. Those that have not peeled off at all (O), those that have more than 80% remaining on the film (0), those that have 50-80% ivy remaining (△)
, those in which only 20% or less remained were indicated as (x).

2) Printing suitability ■ Color development... In order to evaluate pigment dispersibility,
Compare the transparency and density of prints.

■ Gradation reproducibility: Compare the gradation reproducibility by printing with a gravure plate that has continuous gradation.

■ Plate bleatability: Compare the degree of transfer of blue ink to the white board.

The above-mentioned evaluation of each printing aptitude is as follows: the most excellent one is rated as ■, the one where each aptitude does not interfere with printing is rated as O, the one where each aptitude is insufficient is evaluated as Δ, and the one with no aptitude is evaluated as ×.

3) Extrusion lamination strength For each printed matter, use an imine-based AC agent for OPP, an inciamate-based AC agent for PET, and NY, and laminate molten polyethylene using an extrusion laminating machine. After 3 days, cut the sample into a 15 m width and use Yasuda Seiki Co., Ltd. Tested using a peel tester manufactured by the company.
The mold peel strength was measured.

4) Dry lamination strength CI) P film was laminated on each printed matter using a dry lamination machine using a urethane adhesive, and the peel strength was measured in the same manner as the measurement of 3-day extrusion lamination strength.

5) Boiling suitability and retort suitability After lamination, the printed matter is made into a bag, a water/oil mixture is put inside, and the bag is sealed.
After heating at 120° C. for 30 minutes to determine retort suitability, the presence or absence of laminate floating was determined from the appearance. The evaluation was rated as 01 if there was no lamination lifting at all, △ if pinhole-like lamination lifting was observed, and × if delamination occurred on the entire surface.

<Effects of the Invention> As explained above using Examples, the printing ink or coating agent containing the polyurethane resin specified in the present invention has excellent pigment dispersibility and satisfies film performance, printability, or coating suitability. In addition, it has excellent adhesion and suitability for various post-processing.

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Claims (1)

[Scope of Claims] 1) A coating resin composition mainly composed of a pigment, a polyurethane resin, and an organic medium, in which all or part of the polyurethane resin contains a high molecular weight diol or organic diisocyanate having a molecular weight of 300 to 3,000. , the following general formula [
I] and/or the chain extender represented by the following general formula [II
is a reaction product with a reaction terminator represented by ] and contains a ▲numeric formula, chemical formula, table, etc.▼ and/or a tertiary amino group represented by -R_1-N-(R_3)_2 in the molecule. A coating resin composition characterized by being a polyurethane resin. General formula [I]▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the general formula [I], R_1 and R_2 have 1 carbon number.
~5 alkylene group, and R_3 represents an alkyl group having 1 to 5 carbon atoms. Moreover, X is -OH group or -NH_2
Indicates the group. ) General formula [II] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In general formula [II], R_1, R_3 and
] There is no need for the two R_3's to be the same alkyl group at the same time. )