JPS62218456A - Coating resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which is suitable for use in coating the surfaces of various synthetic resin products, gives a printing ink having excellent pigment dispersibility, printability, etc. and has excellent adhesion, consisting of a polyurethane resin obtd. by using a diol component contg. a specified diol as a structural unit, a pigment and an org. medium. CONSTITUTION:A four-membered ring or large lactone (e.g., epsilon-caprolactone) is subjected to a ring opening polymn. reaction in the presence of an initiator composed of a diamine or a diol having the formula (wherein R1 and R2 are each a 1-5C alkylene; R3 is a 1-5C alkyl; and X is NH2 or OH) and a catalyst such as tin caprylate at 100-200 deg.C to obtain a linear lactone polymer (a) having an MW of 500-5,000 and OH groups at both terminals. A diol component consisting of at least 10wt% diol of the component (a) and a polyol type or polyester type diol (b) having an MW of 500-5,000 is reacted with an org. diisocyanate compd., etc., to obtain a polyurethane resin (A). The component A is blended with a pigment (B) (e.g., titanium white, Cyanine Blue pigment) and an org. medium (C) (e.g., ethyl acetate).

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to a coating resin composition, and is particularly a printing ink or coating agent suitable for printing various plastic films and sheets or for surface coating of various synthetic resin products. The aim is to provide a t-cutone compound using a diol or diamine with a special structure as an initiator.
It is characterized by using a polyurethane resin whose diol component is a lactone polymer obtained by ring-opening polymerization.

<Prior art> In recent years, with the diversification of packaging containers and the increasing functionality of synthetic resin products such as synthetic leather, printing inks and various coating agents used for decoration and surface protection such as Buschitta film have also become available. High performance and quality are increasingly required.

In particular, printing ink 1cllN needs to be adapted to make packaging containers more beautiful, more sophisticated, have adhesion to various composite films, and have suitability for various post-processing.

These various suitability are mainly determined by the binder resin used for printing ink etc.
>5trt'ii""0--"7°91, conventional polyurethane resins are those made by reacting diols, @H incyanates, etc. with polyamines as chain extenders as necessary, and diols such as U, 2 [Polyether-type monools such as polyester-type foliols, polyalkylene glycols, polyoxyalkylene glycols, and lactone diols obtained by a bonding reaction between a base and a brecol, but as organic polyincyanates, aliphatic, Cycloaliphatic, aromatic polyisocyanates were commonly used.

<Problems to be Solved by the Present Invention> However, printing inks using these polyurethane resins as adhesives have sufficient adhesion to nylon, polyester films, etc., but are general-purpose films. It does not have sufficient adhesion to polyethylene or polypropylene films, 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, for example, in food containers, etc. This deteriorated the suitability for boiling and retorting.

In order to solve the above-mentioned problems of polyurethane resins, compounds having functional groups such as hydroxyl groups, thiol groups, and halogen atoms are used as chain extenders and reaction terminators in the reaction components of polyurethane resins, and these functional groups are added to polyurethane resins. Attempts are being made to introduce

The present invention attempts to solve the above-mentioned problems of polyflexe resins by using a special lactone polymer as a diol component, rather than using the chain extenders and reaction terminators described above.

Means for Solving the Problems〉 That is, the present invention provides a coating resin composition mainly composed of a pigment, a polyflex resin, and an organic medium,
The present invention aims to provide a coating resin composition characterized in that a lactone polymer obtained using the following special initiator is used as a diol component, which is one of the reaction components of the polyurethane resin. is.

Conventionally, the method for obtaining lactone polymers useful as raw materials for polyflex resins has been to use diols such as ethylene glycol, diethylene glycol, neopentyl glycol, or polyalkylene adipate diols derived from adipic acid and glycols as initiators. It was obtained by ring-opening polymerization of lactones.

On the other hand, the lactone polymer that characterizes the present invention is a lactone polymer obtained by using a compound represented by the following general formula as an initiator.

When a compound represented by the above general formula is used as an initiator to carry out ring-opening polymerization of lactones, a lactone polymer containing 7 tertiary amide groups in the molecule is obtained.

The lactone polymer used in the present invention will be specifically explained below.

The lactones used in the present invention are those having 4 or more, preferably ii:6 or more carbon atoms in the ring. Preferred lactones include 5- or 7-membered ring lactones, such as ε-caprolactone. , γ-rolactone, γ-butyrolactone, and the like.

These lactones may have a substituent such as an alkyl group or an alkoxyl group.

Further, as the initiator that characterizes the present invention, diamines and diols represented by the above-mentioned general formula can be used. In the general formula, R1 and R2 must be alkylene groups having 1 to 5 carbon atoms, and if they have 6 or more carbon atoms, the solubility will decrease. Also, R3 also has 1 to 5 carbon atoms.
It is necessary that the alkyl group is 100%, and if this is exceeded, a problem will arise in the strength of the film. In addition, R1, R2
and R3 may be an alkylene group or an alkyl group having a side chain.

Specific examples of diamines or diols represented by these general formulas include diamines such as methyliminobisethylamine, methyliminobispropylamine, ethyliminobisisopropylamine, N-methyljetanolamine, N-ethyljetanolamine, Examples include diols such as N-methyljetanolamine and N-ethyljetanolamine.

When ring-opening the above-mentioned lactones using the above-mentioned initiator, it can be carried out by a conventionally known method, which involves heating the lactones and the initiator to a temperature in the range of about 100 to 220°C.
Therefore, it can be done.

Incidentally, the ring-opening polymerization must be carried out in the presence of a catalyst to promote the reaction.

These catalysts include organic titanium compounds such as tetrabutyl titanate and tetrabutyl titanate, organic tin compounds such as tin octylate, digtyltin oxide, and dibutyltin oxide, and halogens such as stannous chloride and stannous bromide. Examples include stannous oxide, α05~LOOO
Used in the F range.

The lactone polymer obtained by the method of the present invention is a linear polymer having hydroxyl groups at both ends, and has a molecular weight of usually 500.
~5,000. Note that the molecular weight can be adjusted by determining the molar ratio of the initiator and lactone.

The lactone polymer obtained in this manner is reacted with a conventionally known organic isocyanate compound, if necessary, and a reaction terminator to form the desired polyurethane. It is something that can be obtained.

In addition, as an organic diisocyanate component, tolylene diisocyanate, diphenylmethane diisocyanate,
Xylidine diisocyanate, methylene diisocyanate, isopropylene diisocyanate, hexamethylene diisocyanate, 2-14- or 1-11:2.44-
) Limethylhexamethylene diisocyanate, lysine diisocyanate, 1,4-cyclohexane diisocyanate, inphorone diisocyanate, ζ4-dicyclohexylmethane diisocyanate, and the like.

In addition, from the standpoint of obtaining a resin with excellent solubility,
Alicyclic diisocyanates such as inphorone diisocyanate and 44-dicyclohexylmethane diisocyanate are preferred.

Further, examples of diamines that can be used for elongation cutting include ethylene diamine, propylene diamine, hexamethylene diamine, inphorone diamine, dicyclohexylmethane diamine, and the like.

Further, as the anti-F5 stopper, monoamines such as n-butylamine and monoethanolamine, monoalcohols such as methanol, ethanol, and propyl alcohol, etc. can be used.

Note that it is possible to mix and use the lactone polymer according to the present invention with conventionally known polyether-type diols or polyester-type diols.

Among conventionally known diol components, polyether type diols include polyalkylene glycols such as polyethylene glycol and polypropylene glycol, polyoxyalkylene glycols such as polyoxyethylene propylene glycol and polyoxytetramethylene glycol, Examples include alkylene oxide adducts of bisphenol A such as ethylene oxide, propylene oxide, and ethylene propylene oxide, polycaprolactone diol, polycarbonate diol, etc. using conventional initiators, and polyester type diols such as adipic acid , dibasic acids such as 7-tar acid anhydride, iso-7-tar acid, maleic acid, fumaric acid, succinic acid, etc., and ethylene glycol, diethylene glycol, phlopylene gelicol, 1.4-quinone diol, neopentyl glycol, 1. Examples include those obtained by a condensation reaction with glycols such as 6-hexanediol.

Therefore, it is necessary that these polyether type diols and polyols preferably have a molecular weight of 1,000 to 2,000.
If the molecular weight is below, the polyurethane resin synthesized from the polyurethane resin has the disadvantage that the cohesive force between the resins is excessive, resulting in poor adhesion and lamination properties, and a large amount of residual solvent in printed matter.

cohesive force is insufficient and blocking is likely to occur.

Here, as for the usage amount of the lactone polymer specified in the present invention, it is necessary to use at least 10% by weight or more in the center of the diol component constituting the polyurethane resin.

When using less specific lactone polymers,
The desired effect cannot be obtained.

In addition, in the coating resin composition according to the present invention, it is possible to use the conventional polyurethane resin and the polyurethane resin specified in the present invention in a mixed manner, but in this case, the specified lactone is Similar effects can be obtained when the polymer is contained in an amount of IO weight % or more.

Regarding the manufacturing method of the polyurethane resin used in the present invention, it can be manufactured by a conventionally known method, except that all or part of the conventionally known diol is replaced with a specified lactone polymer as the diol component.

Solvents used at this time include aromatic solvents such as benzene, toluene, and xylene, which are commonly used as printing ink solvents, ester solvents such as ethyl acetate, n-propyl acetate, and butyl acetate, methanol, and ethanol. ,
Alcohol-based solvents such as Improper Tool and n-butanol, and ketone-based solvents such as acetone, methyl ether ketone, and methyl isoptylgtone, either alone or in combination, may be used, but from the viewpoint of the working environment, ester-based solvents, An alcohol-based solvent alone or a mixed solvent is optimal.0 When manufacturing printing ink or coating agent using a polyflex resin solution synthesized using each of the above components, various pigments are added to the polyurethane resin solution. ,
Manufactured by kneading, dispersing, and using additives such as anti-blocking agents and plasticizers, or compatible resins such as nitrified cotton, maleic acid resin, or salt-vinyl acetate copolymer, if necessary. I can do it.

The printing ink or coating agent thus obtained has excellent pigment dispersibility, satisfies film performance, printing suitability or coating suitability, and is also excellent in adhesive properties and suitability for various processing.

Hereinafter, the present invention will be specifically explained using Examples, but the present invention is not limited thereto.

<Example> Synthesis Example 1 N-methyljetanolamine 1 was placed in a four-loaf flask equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser.
&4 parts and 250 parts of dibutyl tin sulfate α05s1ε-caprolactone were charged and reacted at 170°C for 5 hours to obtain a lactone polymer (4) having a hydroxyl value of 574, an acid value α8, and a melting point of 82 to 87°C.

Synthesis Example 2 Using the same apparatus as in Example 1, methyliminobispropylamine 1&7@, 05 parts of dibutyl tin chloride, and 250 parts of ε-caprolactone were charged and reacted in the same manner, resulting in a hydroxyl value of 59.0 parts and an acid value of α8. , melting point 55-60℃
A lactone polymer (B) was obtained.

Comparative Synthesis Example 1 Using the same equipment as in Example 1, ethylene glycol &
0211<, 250 parts of ε-caprolactone, and 05 parts of dibutyl tin chloride α were charged and reacted in the same manner to obtain a lactone polymer (C) having a hydroxyl value of 5 & 1, an acid value α of 1, and a melting point of 50 to 60°C.

Synthesis Examples 1 to 4 of Polyurethane Resin 1 Isophorone diisocyanate 444 was placed in a fourth flask equipped with a stirrer, thermometer, Dimroth, and nitrogen gas inlet tube.
Lactone polymers A, B, and C obtained in Synthesis Examples 1 to 2 and Comparative Synthesis Example 1 and polyester diol (molecular weight zoooo) synthesized from adipic acid and 1.4-butanediol (diol D) ) each 2
00 parts of each were charged separately and reacted for several hours while adding nitrogen gas to the same amount. After cooling, 285 parts of ethyl acetate was added to dissolve the mixture uniformly, 156 parts of Improvil alcohol and 1 & 6 parts of Inphorondiamine were added, and further 29 parts of Motuptilamine were added to stop the reaction. Polyurethane resin solution A', B', C', and D' were obtained, respectively.

Synthesis Examples 5 to 7 of Polyurethane Resin Polyurethane resin solution E', Obtain F' and G'.

Examples 1 to 4, Comparative Examples 1 to 2 Each of the resin solutions A' to G'gog obtained in Polyurethane Resin Synthesis Examples 1 to 7 was mixed with 25 parts of Improvil alcohol, and for white ink, 30 parts of titanium oxide and acetic acid. For blue ink, add 20 parts of ethyl, Shaninpur pigment iog
, ethyl acetate 85s is added and kneaded to produce each printing ink.

Examples 1 to 4 used resin solutions A', B', F', and G', and Comparative Examples 1 to S used resin solutions C', D', and E'.

Evaluation Test Using each of the printing inks obtained in Examples 1 to 4 and Comparative Examples 1 to B, the adhesion to various films, suitability for printing, suitability for lamination, and suitability for boiling and retorting were evaluated, and the results are shown. Shown in 1.

In addition, each evaluation method is based on the method described below.

1) Adhesiveness When each test ink was printed on a designated film using a gravure proofing machine and left for one day, sellotape was applied to the printed surface and this was rapidly peeled off, the printed film did not come off at all. (◎) Those with more than 80% growth on the film (○), those with 50 to 80 inches left (△), 20
Items that were cut less than % are indicated as (×).

2) Printing suitability ■Coloring properties: Compare the transparency and density of the stamps in order to evaluate the pigment fractionality.

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

The above-mentioned evaluation of each printing aptitude is evaluated as ◎ for the best one, 0 for each aptitude that does not interfere with printing, Δ for each aptitude that is insufficient, and X for no aptitude.

8) Extrusion laminate strength For each printed matter KOPP, imine type, PET.

For NY, an isocyanate-based AC agent was used, and molten polyethylene was laminated using an extrusion laminating machine. After 8 days, the sample was cut into 155 m wide pieces and the T-type oxidation strength was measured using a peel tester made by Yasuda Seiki Co., Ltd. 4) Dry lamination strength A CPP film was laminated on each printed matter using a dry lamination machine using a Frethane adhesive, and the acid strength was measured in the same manner as the lamination strength measurement after 8 days.

5) Boiling suitability and retort suitability After lamination, the printed matter is made into bags, filled with a mixture of SK water/oil, and sealed at 90°C for boiling suitability.
After heating at 120° C. for 80 minutes and retort suitability, the presence or absence of laminate floating was determined based on appearance.

- [ci3- A sample with no lamination lifting at all was evaluated as ◯, a case with pinhole-like lamination lifting was evaluated as △, and a sample with full-surface delamination was evaluated as ×.

Effects of the Invention> As shown in the Examples above, polyurethane resins using the lactone crosslinker obtained by the method of the present invention as a diol component can produce various plastic films that could not be obtained by using conventional diol components. It shows a wide range of adhesion to substrates such as.

Furthermore, printing inks and the like using the polyflex resin according to the present invention are excellent in pigment dispersibility, suitability for various types of printing and coating, and the like.

Claims (1)

[Claims] (1) In a coating resin composition mainly composed of a pigment, a polyurethane resin, and an organic medium, at least 10% by weight of the diol component constituting the polyurethane resin.
A coating resin composition characterized in that the above is a lactone polymer obtained by ring-opening polymerization of lactones using a compound represented by the following general formula as an initiator. General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the general formula, R_1 and R_2 represent an alkylene group having 1 to 5 carbon atoms, R_3 represents an alkyl group having 1 to 5 carbon atoms, and X is - Indicates NH_2 group or -OH group.)