JPH10195356A - Ink composition for use in jet printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink composition which can form a printed coating which is excellent in the adhesion to a shaped article, a film, a fiber product or the like containing a polyoefin resin base as a main material component, and also has good storage stability when used for a storing container or a nozzle head, by incorporating a chlorinated polyolefin resin and an imino group- containing dye and/or an imino group-containing substance in the composition. SOLUTION: This ink composition comprises 100 pts.wt. chlorinated polyolefin having a chlorine content of 10 to 60wt.% and a weight average molecular weight of 1,000 to 100,000, 50 to 1000 pts.wt. dye having an imino (=NH) group in its molecular structure or containing an imino group as an adduct in its molecule and 50 to 500 pts.wt. imino group-containing dye and/or an imino group-containing substance, for example an imino group-containing resin such as a polyamide resin, P-toluene sulfonic acid amide resin or the like. The composition further comprises a colorant, a solvent, and optionally other additives such as an electric conductivity-adjusting agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a jet printing ink composition which can form a printed film having excellent adhesion to a polyolefin resin, is non-corrosive and has excellent storage stability.

[0002]

2. Description of the Related Art Polyolefin resins are crystalline,
In addition, since the surface does not have a highly reactive functional group, it is generally difficult to bond or coat the polyolefin resin substrate. In order to improve this point, some attempts have been made to improve the adhesion of the coating film by modifying the resin surface by a physical method such as acid treatment, corona discharge or plasma treatment. However,
In these cases, the process becomes complicated or a huge capital investment is required. Further, even if such complicated processes and capital investment are carried out, it is not always possible to obtain an effect corresponding to the investment.

A printing ink composition containing a chlorinated polyolefin such as chlorinated rubber, chlorinated polyethylene, or chlorinated polypropylene forms a print film having excellent adhesion to a plastic film, especially a polyolefin film such as polypropylene. be able to. However, these ink compositions are disadvantageous in that dehydrochlorination occurs during storage, which tends to cause deterioration of the quality of the ink composition, deterioration of storage stability, and corrosion of the container. Therefore, in order to make up for the above-mentioned drawbacks, it is common practice to add a stabilizer to the ink composition.

Conventionally, stabilizers used in printing ink compositions containing chlorinated polyolefins include allyl glycidyl ether, phenyl glycidyl ether, diglycidyl ether of bisphenol A, epoxidized vegetable oil,
Epoxidized fatty acids and their esters, epoxy group-containing compounds of cyclohexane, aromatic amines such as aniline and phenylenediamine, metal soaps such as calcium salt, cadmium salt and lead salt of stearic acid, phosphoric acid, boric acid and dihydrogen phosphate Oxygen acids such as potassium, succinic acid, and sodium citrate, organic acids, and alkali metal salts thereof are used.

[0005] However, most of the above-mentioned stabilizers only act as a hydrochloric acid scavenger, so that for a short period after the addition of the stabilizer, it is possible to scavenge the hydrochloric acid generated by the decomposition of the chlorinated polyolefin. After capturing a certain amount, the trapping effect is lost, and therefore, stability cannot be maintained over a long period of time, nor can stability be maintained under severe conditions such as high temperature and high humidity.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems of the conventional ink composition.
That is, a polyolefin-based resin base material, for example, propylene homopolymer, ethylene-propylene copolymer, ethylene-propylene-butene copolymer in the form of a molded product or the same film or the same fibrous product as the main component, the adhesion to the same An object of the present invention is to provide an ink composition for jet printing which can form an excellent printed film, is non-corrosive to a storage container, a nozzle head, and the like and has excellent storage stability.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found that an ink composition for jet printing containing a chlorinated polyolefin resin contains a dye containing an imino group and / or a dye. The present inventors have found that the above problems can be solved by using an imino group-containing substance, and have completed the present invention. That is, the ink composition for jet printing of the present invention is characterized by containing a chlorinated polyolefin resin and an imino group-containing dye and / or an imino group-containing substance.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The chlorinated polyolefin resin used in the present invention preferably has a chlorine content of 10 to 60% by weight and a weight average molecular weight of 1,000 to 100,000, more preferably 300 to 100,000.
The chlorinated polyolefin-based resin is, for example, chlorinated polyethylene, chlorinated polypropylene, chlorinated rubber, or an acrylic monomer or urethane having an ethylenically unsaturated bond. And the like.

The imino group-containing dye used in the present invention is a dye having an imino group (= NH group) in the molecular structure or a dye having an imino group added to the molecule. These dyes are not particularly limited. Can be used without. Examples of the imino group-containing dye include CI Solvent Black 2
8, CI Solvent Blue 70, CI Basic Blue 5,
7, CI Basic Violet 1, 3, CI Basic Red1,
8, CI Acid Black 2 and the like. The imino group-containing substance used in the present invention can be used without particular limitation as long as it contains an imino group and is soluble in the solvent used.
-Resins containing imino groups, such as toluenesulfonic acid amide resins, can be used.

The jet printing ink composition of the present invention containing a chlorinated polyolefin resin and an imino group-containing dye and / or an imino group-containing substance is non-corrosive to storage containers, nozzle heads and the like. The reason for this is not always clear at the moment, but it is considered as follows. In a conventional chlorinated polyolefin resin-containing ink composition, hydrochloric acid is generated due to decomposition of the chlorinated polyolefin resin, and chlorine ions of the hydrochloric acid cause corrosion. On the other hand, a polar group such as an imino group has particularly excellent adsorptivity to a metal surface and is known as an inhibitor for forming an oriented and high-density film. The ink composition forms an adsorbed layer of imino group-containing dye molecules on the surface of the storage container or nozzle head that comes into contact, and the adsorbed layer prevents the entry of chloride ions and prevents contact between chloride ions and metal surfaces It is considered that corrosion is suppressed.

In the ink composition for jet printing of the present invention, the amount of the imino group-containing dye is usually 50 parts by weight per 100 parts by weight of the chlorinated polyolefin resin component.
To 1000 parts by weight, more preferably 80 to 800 parts by weight. When the content is less than 50 parts by weight, the desired effect tends to be insufficient. On the contrary, when the content is more than 1000 parts by weight, it tends to be difficult to maintain the performance as an ink composition. Absent. The amount of the imino group-containing substance is usually 50 to 500 parts by weight, based on 100 parts by weight of the chlorinated polyolefin resin component.
More preferably, it is 100 to 400 parts by weight. When the content is less than 50 parts by weight, the desired effect tends to be insufficient. On the other hand, when the content is more than 500 parts by weight, the performance as an ink composition tends to be difficult to maintain, so that it is preferable. Absent.

To the ink composition for jet printing of the present invention, a coloring agent other than the above imino group-containing dye, a solvent, and if necessary, an electric conductivity adjusting agent, a surfactant, an ultraviolet absorber, a quencher and the like are added. An agent can be compounded. As the above-mentioned colorant that can be used in the present invention, those that are compatible with other ink composition components and soluble in a solvent are preferable. Representative colorants that can be used in the present invention include CI
Solvent Black 22, 27, 29, CI Solvent Red 8
3, 1, 125, 132, CI Solvent Blue 47, 4
8, CI Solvent Yellow 88, 89, basic dye,
Dyes such as acid dyes, and inorganic or organic pigments such as titanium oxide, carbon black, iron oxide, zinc sulfate, oily smoke, graphite, red iron oxide, phthalocyanine blue, phthalocyanine green, brilliant carmine 6B, and lake red C. However, when an insoluble dye or pigment is used, the particle diameter is 3 μm to prevent clogging of the nozzle.
Hereinafter, those having a diameter of 1 μm or less are particularly preferable. When a colorant is used, its amount is usually 50 parts by weight based on 100 parts by weight of the chlorinated polyolefin-based resin component.
To 1000 parts by weight, preferably 80 to 800 parts by weight.

In the present invention, a solvent is used to appropriately adjust the viscosity of the ink composition. Accordingly, various solvents can be used without particular limitation as long as they are compatible with other components. Representative examples of the solvent that can be used in the present invention include ketones such as acetone, methyl ethyl ketone and cyclohexanone, alcohols such as methanol, ethanol and isopropanol, and ethers such as cellosolve and butyl cellosolve. In order to improve the solubility of the chlorinated polyolefin, it is possible to add an aromatic solvent, toluene, xylene and the like. The amount of the solvent is determined in consideration of the viscosity of the ink composition, surface tension, and the like.
50 to 95% by weight of the ink composition, preferably 70 to 9%
Suitably, it is 0% by weight.

The ink composition for jet printing of the present invention needs to have properties suitable for an ink jet printing method.
Therefore, the ink composition is 1 to 10 mPa · s (20
C.) in the range of 20 to 70 mN / m (20.degree. C.). When preparing the ink composition for jet printing of the present invention, after mixing and stirring each component, the diameter of the nozzle of the jet printer to be used, for example, filtered through a filter having a pore size of about 1/10 or less. To purify.

The ink composition for jet printing of the present invention can be used in a conventionally known jet printer.
Conventionally known jet printers include, for example, a charge control system, an ink-on-demand system, and a system in which an ink composition is ejected by a thermal head.
The ink composition printed by inkjet printing is from room temperature to several tens.
Dry at 00 ° C. to form a film.

The object which can be printed using the ink composition for jet printing of the present invention is not particularly limited as long as it does not deform or deteriorate under the temperature conditions at which the printed ink composition is dried. Not something. For example, it can be printed on the surface of a base material such as metal, glass, plastic, especially a polyolefin resin, paper coated with the surface of the resin, particularly a polypropylene laminated paper, or a transparent sheet for an overhead project.

According to the present invention, it is possible to form a print film having excellent adhesion as compared with a conventional ink composition for jet printing, and to provide a jet printing ink which is excellent in non-corrosiveness to nozzle heads and the like. A composition was obtained. The present invention is also useful for improving non-corrosiveness and storage stability of an ink containing a substance which contains chlorine and ionizes chlorine in addition to the chlorinated polyolefin.

[0018]

The present invention will be described below in more detail with reference to examples and comparative examples. In the following Examples and Comparative Examples, “parts” and “%” are based on weight. Examples 1 to 7 and Comparative Examples 1 to 4 The components shown in Table 1 were used in the amounts (parts) shown in Table 1 and uniformly mixed, followed by filtration through a membrane filter having a pore size of 1.0 μ and purification. Jet printing ink compositions corresponding to the examples and the comparative examples were prepared.

The components used were as follows.
A chlorinated polyolefin resin having a chlorine content of 25% and an Mw of about 30,000 (described as “chlorinated PO resin A” in Table 1), a chlorinated polyolefin resin having a chlorine content of 40% and an Mw of about 30,000 (in Table 1, A chlorinated PO resin B), a novolak type phenol resin having an Mw of about 2000 (described as "phenol resin" in Table 1), a methyl methacrylate resin having an Mw of about 10,000 ("acryl resin" in Table 1) Resin having a Mw of about 15000 and an NV = 50% having a dimethylpolysiloxane in the side chain (described as “silicone acrylic resin” in Table 1), and a carbon black content of 50. % Of carbon-epoxy resin graft type powder colorant (in Table 1, Described as over ").

Each of the obtained ink compositions for jet printing is jetted out onto a polypropylene film in a predetermined image by a jet printer to form a print film, and the print film is subjected to an adhesion test and a cellophane peel test. Carried out. In addition, a corrosion test and a storage stability test were performed for each ink composition for jet printing on a printer material.

The test conditions were as follows: Adhesion test: After forming a printed film on a polypropylene film with a jet printer, the film was rubbed and rubbed, and the presence or absence of the dot film peeling was checked. The evaluation was based on the following criteria. ○: No abnormality ×: Confirmation of peeling Cellophane tape peeling test: After forming a print film on a polypropylene film with a jet printer, attach cellophane tape to the printed part, peel off the cellophane tape, and check for the presence of dot film peeling. Evaluation was based on criteria. ○: No abnormality ×: Confirmation of peeling

Corrosion test for printer material: SUS303, SUS30 considered as printer material
4. SUS316 pellets were immersed in an ink composition containing 10% ion-exchanged water, and the corrosion and alteration of the pellets after one month at 60 ° C. was confirmed and evaluated according to the following criteria. ：: No abnormality ×: Corrosion confirmation Storage stability test: 60 parts of each ink composition for jet printing
C. for 1 month or at -5.degree. C. for 1 month. The viscosities before and after the storage were measured by an Ostwald viscometer and evaluated according to the following criteria. ：: when the difference from the initial viscosity is within 0.5 centipoise ×: when the difference from the initial viscosity exceeds 0.5 centipoise The results are as shown in Table 1.

[0023]

[Table 1]

As is clear from the data in Table 1, the ink compositions of Examples 1 to 7, which are the ink compositions for jet printing of the present invention, are excellent in non-corrosiveness and storage stability with respect to the material of the printer. In addition, it is possible to form a printed film having excellent adhesion and cellophane tape peeling resistance. on the other hand,
Printed films obtained using the ink compositions of Comparative Examples 1 and 3 containing no chlorinated polyolefin have poor adhesion and cellophane tape peeling resistance. The ink compositions of Comparative Examples 2 and 4 containing no imino group-containing dye or imino group-containing substance,
Corrosive to printer material, causing corrosion.

[0025]

The ink composition for jet printing of the present invention can form a print film having excellent adhesion to a polyolefin-based resin and is non-corrosive to storage containers and nozzle heads. Yes, excellent storage stability.

Claims (3)

[Claims] 1. An ink composition for jet printing, comprising a chlorinated polyolefin resin and an imino group-containing dye and / or an imino group-containing substance. 2. A chlorinated polyolefin resin having a chlorine content of 10 to 60% by weight and a weight average molecular weight of 1,000 to 100,000, and an imino group-containing dye in an amount of 50 to 1,000 parts by weight based on 100 parts by weight of the chlorinated polyolefin resin. The ink composition for jet printing according to claim 1, further comprising 50 to 500 parts by weight of an imino group-containing substance based on 100 parts by weight of the chlorinated polyolefin resin. 3. A chlorinated polyolefin resin 10 comprising a colorant other than the imino group-containing dye and / or the imino group-containing substance.
The ink composition for jet printing according to claim 1 or 2, further comprising 50 to 1000 parts by weight based on 0 part by weight.