JP3779487B2 - Vehicle for printing ink - Google Patents

Description

【００２２】
【発明の効果】
以上の本発明によれば、本発明の印刷インキ用ビヒクルを使用することにより被印刷物（食品包装剤用プラスチックフィルム、金属箔等の）との密着性に優れた印刷インキの製造が可能である。又、この印刷インキが印刷された被印刷物を用いることにより、優れたボイル適性を有する食品包装材が提供される。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printing ink vehicle comprising a polyurethane polyurea resin solution. The printing ink using the printing ink vehicle of the present invention can be applied to various plastic films used as printed materials, in particular, so-called flexible packaging films such as treated polypropylene film, polyester film and nylon film, and the films are laminated. Or is suitable for applications where a film and a metal foil are bonded together.
[0002]
[Prior art]
Although there are many examples where the use of polyurethane polyurea is proposed as a vehicle for printing inks used for plastic films as packaging materials, it has excellent adhesion to any of treated polypropylene films, polyester films, and nylon films as printed materials ( None have adhesiveness.
[0003]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a printing ink vehicle having excellent adhesion to any of a treated polypropylene film, a polyester film and a nylon film as a substrate.
As a result of intensive investigations to achieve the above object, the present inventors have made a vehicle of a polyurethane polyurea resin solution containing substantially no chlorine and having a specific amount of amino group bonded to the terminal, so that any of the above can be achieved. The present inventors have found that a printing ink having excellent adhesion can be obtained with respect to the above film.
[0004]
[Means for Solving the Problems]
The above object is achieved by the present invention described below. That is, in the present invention, the main component of the vehicle is a prepolymer obtained by reacting m-tetramethylxylylene diisocyanate or 1,3-bis (isocyanatomethyl) cyclohexane with a polyol, and further a polyamine is a chain extender. A polyurethane polyurea resin solution having an amino group at the end, obtained by reacting as follows: The content of amino groups per gram of the polyurethane polyurea resin is 15 to 100 μg equivalent, and the polyurethane polyurea resin solution is substantially Is a vehicle for printing ink characterized by not containing chlorine.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described in more detail with reference to preferred embodiments of the invention.
Printing inks usually consist of colorants consisting of pigments and / or dyes, and vehicles and auxiliaries consisting of oils, resins, plasticizers, waxes and solvents (viscosity adjustment, color adjustment, dispersibility adjustment, dryness adjustment, etc.). Composed.
The present invention is characterized in that the above-mentioned polyurethane polyurea resin solution is used as a main component of a printing ink vehicle.
The polyurethane polyurea resin used in the present invention is a resin obtained by reacting a polyol and polyisocyanate to form a prepolymer and reacting this with a polyamine as a chain extender according to a conventional method.
[0006]
In producing the polyurethane polyurea resin of the present invention, a conventionally known polymer polyol can be used as the polyol component. The polymer polyol preferably has a number average molecular weight of 500 or more and 6000 or less. If it is less than 500, the re-solubility of the polyurethane polyurea resin in the solvent becomes poor, and it becomes difficult to obtain high-speed printing suitability of the printing ink. If it exceeds 6000, the heat resistance of the polyurethane polyurea resin becomes poor, and the printed matter required as the printing ink. It is difficult to obtain blocking resistance during winding. A more preferred number average molecular weight is 2000 to 4000.
[0007]
The polyisocyanate used in the present invention is preferably a diisocyanate compound. A conventionally known diisocyanate compound can be used as the diisocyanate compound, but the diisocyanate compounds supplied industrially are mostly produced by the phosgene method and contain chlorine as an impurity.
In order that the printing ink using the vehicle of the present invention can also be used for printing food packaging materials, it is not preferable to use a diisocyanate compound containing chlorine as an impurity, a method that does not use phosgene and does not contain chlorine as an impurity, For example, m-tetramethylxylylene diisocyanate produced by the dimethyl carbonate method or the like (for example, there is a product of American Cyanamide Co., Ltd. as a commercial product, hereinafter abbreviated as m-TMXDI) or 1,3-bis (isocyanate). ) cyclohexane (e.g., as a Mitsubishi Gas Chemical's product is Ru Oh. hereinafter commercially be mentioned as abbreviated as 1, 3-BIC.) or the like are preferable.
[0008]
In the present invention, the polyurethane polyurea resin is used as a solution. For example, the resin can be used by separating the resin from a solution of the resin produced in a solvent. This is advantageous.
Therefore, in order to obtain a polyurethane polyurea resin solution containing substantially no chlorine, it is preferable to use a diisocyanate compound having a chlorine content of 10 ppm or less. In this case, the polyurethane polyurea resin separated from the solution is substantially free of chlorine.
In the present invention, the chlorine content of the diisocyanate compound refers to the content of total chlorine such as chlorine bonded to the diisocyanate compound and chlorine compounds mixed in the diisocyanate compound in other forms.
[0009]
As the chain extender, conventionally known amines having two or more amino groups in the molecule (for example, isophoronediamine, ethylenediamine, hexamethylenediamine, diaminopropylamine, pentaethylenehexamine, N-aminoethylpiperazine, m-xylene) Diamine, hydrazine, etc.) can be used. If necessary, diols and monoamines as reaction terminators can be used in combination.
In the present invention, the treated polypropylene film, which is a printing ink and a printing material, has an amino group bonded to the terminal of the polyurethane polyurea resin obtained by reacting the above raw material components in an amount of 15 to 100 μg equivalent per 1 g of the resin. It is necessary for sufficient adhesion with polyester film and nylon film. When the amino group content is less than 15 μg equivalent, the adhesiveness to the above-mentioned printed material is poor, and when it exceeds 100 μg equivalent, the suitability for boil after lamination is deteriorated. Preferably it is 30-60 microgram equivalent. The content of the terminal amino group can be adjusted by the blending ratio of the urethane prepolymer, the diamine as a chain extender, and the reaction terminator.
[0010]
Examples of the solvent used for the production of the polyurethane polyurea resin of the present invention include aromatic hydrocarbon solvents such as benzene, toluene and xylene, which are well known as solvents for ordinary printing inks; cyclohexane, methylcyclohexaneethylcyclohexane and the like. Saturated hydrocarbon solvents; ester solvents such as methyl acetate, ethyl acetate, and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; alcohol solvents such as methanol, ethanol, isopropanol, and butanol; These can be used alone or in combination.
[0011]
If necessary, a vehicle resin other than the polyurethane polyurea resin of the present invention may be added to the vehicle for printing ink of the present invention containing the above-mentioned polyurethane polyurea resin solution as a main component as long as the object of the present invention is not impaired. You can also.
A printing ink is produced by mixing the printing vehicle of the present invention with a colorant and various auxiliaries according to a conventional method. The concentration of the polyurethane polyurea resin in the vehicle is not particularly limited, but is usually 10 to 40% by weight.
In the printing ink using the vehicle for printing ink of the present invention, there is no harmful chlorine around the urethane, urea group and terminal amino group in the polyurethane urea resin molecule used in the present invention. It is considered that excellent adhesiveness, laminate strength, and post-processing suitability are exhibited.
[0012]
【Example】
Next, the present invention will be described more specifically with reference to examples. Parts in the text are based on weight unless otherwise noted.
[0013]
Example 1
A reaction vessel was charged with 500 parts of a polyester diol having a number average molecular weight of 2000 obtained from adipic acid and neopentyl glycol and 122 parts of m-TMXDI (manufactured by American Cyanamide), and reacted at 100 ° C. for 5 hours in a nitrogen stream. A urethane prepolymer having an NCO group content of 3.07% was obtained. This urethane prepolymer was dissolved in ethyl acetate to obtain a urethane prepolymer solution having a nonvolatile content of 63%. A mixed solution consisting of 37.1 parts of isophoronediamine, 5.85 parts of di-n-butylamine, 386 parts of isopropyl alcohol and 772 parts of methylcyclohexane was added dropwise to the urethane prepolymer solution while stirring the solution. Non-volatile content 30%, viscosity 1050 mPa.s. s, a polyurethane polyurea solution having a terminal amino group content of 12 μg equivalent was obtained. Chlorine was not detected from this polyurethane urea solution.
[0014]
Comparative Example 1
A reaction vessel was charged with 500 parts of a polyester diol having a number average molecular weight of 2000 obtained from adipic acid and neopentyl glycol and 111 parts of isophorone diisocyanate (manufactured by Huls: Phosgene method), and reacted at 100 ° C. for 5 hours under a nitrogen stream. A urethane prepolymer having an NCO group content of 3.12% was obtained. This urethane prepolymer was dissolved in ethyl acetate to obtain a urethane prepolymer solution having a nonvolatile content of 63%.
37.0 parts of isophorone diamine, 5.86 parts of di-n-butylamine, 385 parts of isopropyl alcohol and 771 parts of methylcyclohexane were mixed to prepare a mixed solution, and the above urethane prepolymer solution was dropped into this while stirring. , Non-volatile content 30%, viscosity 1150 mPa.s. s, a polyurethane polyurea solution having a terminal amino group content of 12 μg equivalent was obtained. 8.4 ppm of chlorine was detected from this polyurethane polyurea solution.
[0015]
Example 2
A reaction vessel was charged with 300 parts of polytetramethylene glycol having a number average molecular weight of 3000, 200 parts of polycaprolactone diol having a number average molecular weight of 2000, and 68.5 parts of 1.3-BIC, and reacted at 100 ° C. for 5 hours in a nitrogen stream. A urethane prepolymer having an NCO group content of 2.10% was obtained. This urethane prepolymer was dissolved in ethyl acetate to obtain a urethane prepolymer solution having a nonvolatile content of 63%.
A solution was prepared by mixing 25.9 parts of isophoronediamine, 347 parts of isopropyl alcohol and 693 parts of methylcyclohexane, and the above urethane prepolymer solution was added dropwise to this solution while stirring, and the non-volatile content was 30% and the viscosity was 1000 mPa.s. s, a polyurethane polyurea solution having a terminal amino group content of 25 μg equivalent was obtained. Chlorine was not detected from this polyurethane polyurea solution.
[0016]
Comparative Example 2
In a reaction vessel, 300 parts of polytetramethylene glycol having a number average molecular weight of 3000, 200 parts of polycaprolactone diol having a number average molecular weight of 2000, and dicyclohexylmethane-4,4 ′ diisocyanate (Desmodule W: phosgene method manufactured by Bayer) 92. 5 parts were charged and reacted at 100 ° C. for 5 hours under a nitrogen stream to obtain a urethane prepolymer having an NCO group content of 2.03%. This urethane prepolymer was dissolved in ethyl acetate to obtain a urethane prepolymer solution having a nonvolatile content of 63%.
26.2 parts of isophorone diamine, 361 parts of isopropyl alcohol and 721 parts of methylcyclohexane were mixed to obtain a solution, and the urethane prepolymer solution was dropped into the solution while stirring to give a nonvolatile content of 30% and a viscosity of 1450 mPa.s. s, a polyurethaneurea solution having a terminal amino group content of 26 μg equivalent was obtained. From this polyurethane polyurea solution, 34.4 ppm of chlorine was detected.
[0017]
Example 3
A reaction vessel was charged with 500 parts of a polyester diol having a number average molecular weight of 4000 obtained from adipic acid and 3-methyl-1,5-pentanediol and 53.3 parts of 1,3-BIC, and the mixture was stirred at 100 ° C. for 5 hours under a nitrogen stream. A urethane prepolymer having an NCO group content of 2.06% was obtained by reaction. This urethane prepolymer was dissolved in ethyl acetate to obtain a urethane prepolymer solution having a nonvolatile content of 63%.
A solution was obtained by mixing 25.2 parts of isophoronediamine, 337 parts of isopropyl alcohol and 673 parts of methylcyclohexane. The urethane prepolymer solution was added dropwise to this solution while stirring to add a non-volatile content of 30% and a viscosity of 1000 mPa.s. s, a polyurethane polyurea solution having a terminal amino group content of 18 μg equivalent was obtained. Chlorine was not detected from this polyurethane polyurea solution.
[0018]
Comparative Example 3
In a reaction vessel, 500 parts of a polyester diol having a number average molecular weight of 4000 obtained from adipic acid and 3-methyl-1,5-pentanediol and 1,3-bis (isocyanatomethyl) cyclohexane (Takenate 600, Takeda Chemical Industries, Ltd .: Phosgene method) 53.3 parts were charged and reacted at 100 ° C. for 5 hours under a nitrogen stream to obtain a urethane prepolymer having an NCO group content of 2.06%. This urethane prepolymer was dissolved in ethyl acetate to obtain a urethane prepolymer solution having a nonvolatile content of 63%.
A solution comprising 25.2 parts of isophoronediamine, 337 parts of isopropyl alcohol and 673 parts of methylcyclohexane was prepared, and the urethane prepolymer solution was added dropwise thereto while stirring to add a nonvolatile content of 30% and a viscosity of 1150 mPa.s. s, a polyurethane polyurea solution having a terminal amino group content of 18 μg equivalent was obtained. From this polyurethane polyurea solution, 106.4 ppm of chlorine was detected.
[0019]
Evaluation of printing ink using the above-mentioned polyurethane polyurea solution as a vehicle 40 parts of each polyurethane polyurea solution of Examples 1-3 and Comparative Examples 1-3, 35 parts of rutile titanium white, 10 parts of methylcyclohexane and isopropyl A white ink is prepared by kneading a mixed solution having a composition of 15 parts of alcohol, and the viscosity is adjusted to a # 3 Zahn cup for 20 seconds with a mixed solvent of methylcyclohexane, methyl ethyl ketone, and isopropyl alcohol (weight ratio 50:30:20). Thus, a printing ink was prepared.
Using this printing ink, a 40 μm thick corona discharge-treated biaxially stretched polypropylene film (hereinafter abbreviated as OPP) and a 12 μm thick biaxially stretched polyethylene terephthalate film (with a gravure printing machine equipped with a 35 μm gravure plate) (Hereinafter abbreviated as PET) and a corona discharge-treated biaxially stretched nylon film (hereinafter abbreviated as ONY) having a thickness of 15 μ, each of which was overprinted twice and dried at 50 ° C. to obtain a white printed film. Each white printing film was evaluated by the following method, and the evaluation results are shown in Table 1.
[0020]
(1) Adhesiveness The printed surface when the white printed film obtained after standing for 1 day is peeled off with a cellophane tape attached to the printed surface at a slow speed of about 5 mm / min at an angle of 60 degrees. The state of was visually determined. The determination criteria were as follows.
◎ …… Ink did not peel off at all ○ ・ ・ ・ ・ ・ 80% or more of the ink remained on the film △ ・ ・ ・ ・ ・ 50% or more of the ink remained on the film × ・ ・ ・ ・ ・50% or more of the ink was peeled off (2) A toluene solution of an isocyanate-based anchor coating agent was applied on the printing surface of a boilable ONY printing film so that the dry film was 0.2 μm, and dried at 50 ° C. Low density polyethylene was extruded and laminated. After heat-melting the polyethylene side of the obtained laminate film to make a pouch and filling it with a mixture of salad oil / vinegar / water = 1/1/5 (weight ratio) and sterilizing by boiling at 100 ° C. for 30 minutes The appearance of was evaluated. Judgment criteria are as follows.
○ …… There is no abnormality in the appearance. △ …… Blisters are generated in some areas. × ・ ・ ・ ・ ・ Delamination is occurring. [0021]
Table 1

[0022]
【The invention's effect】
According to the present invention described above, it is possible to produce a printing ink having excellent adhesion to a printing material (such as a plastic film for food packaging, a metal foil) by using the printing ink vehicle of the present invention. . Moreover, the food packaging material which has the outstanding boil aptitude is provided by using the to-be-printed material on which this printing ink was printed.

Claims (3)

The main component of the vehicle is obtained by further reacting a prepolymer obtained by reacting m-tetramethylxylylene diisocyanate or 1,3-bis (isocyanatemethyl) cyclohexane with a polyol as a chain extender. A polyurethane polyurea resin solution having an amino group at the terminal, the amino group content per gram of the polyurethane polyurea resin is 15 to 100 μg equivalent, and the polyurethane polyurea resin solution is substantially free of chlorine. A vehicle for printing inks characterized by 2. The printing according to claim 1, wherein the polyurethane polyurea resin is produced using m-tetramethylxylylene diisocyanate or 1,3-bis (isocyanatomethyl) cyclohexane having a chlorine content of 10 ppm or less as a raw material component. Ink vehicle.   The vehicle for printing ink according to claim 1, which is for printing ink for plastic films for food packaging materials and metal foils.