CN112457715A

CN112457715A - Solvent-free UV ink-jet for long-time continuous jet printing and preparation method thereof

Info

Publication number: CN112457715A
Application number: CN202011317474.0A
Authority: CN
Inventors: 苏志国
Original assignee: Xiamen Gelintai New Material Science & Technology Co ltd
Current assignee: Xiamen Gelintai New Material Science & Technology Co ltd
Priority date: 2020-11-23
Filing date: 2020-11-23
Publication date: 2021-03-09

Abstract

The invention provides a solvent-free UV ink-jet for long-time continuous jet printing, which comprises 20-80 parts of monofunctional monomer, 20-60 parts of bifunctional monomer, 1-30 parts of acrylic oligomer, 1-25 parts of nano pigment, 1-20 parts of photoinitiator, 0.1-1 part of dispersant, 0.1-1 part of flatting agent, 0.1-1 part of defoaming agent and 1-25 parts of auxiliary agent, wherein the auxiliary agent, the dispersant and the nano pigment are added into the monofunctional monomer, the rotation speed is adjusted, the mixture is uniformly stirred, then a sand mill is used for grinding, the flow during grinding is controlled, the color paste with required fineness is prepared, then other components are added into the color paste, and the solvent-free UV ink is obtained after the uniform stirring. The invention has low viscosity, good fluidity and high stability, shows stable printing quality in a long-time continuous printing process, shows good adhesive force when jetting ink on various different materials, is environment-friendly, has low production cost and can be suitable for high-speed and batch printing.

Description

Solvent-free UV ink-jet for long-time continuous jet printing and preparation method thereof

Technical Field

The invention relates to the technical field of ink preparation, in particular to a solvent-free UV ink-jet for long-time continuous jet printing and a preparation method thereof.

Background

The UV ink can be cured and dried quickly under the irradiation of ultraviolet lamp light, has the advantages of high curing speed, little pollution, environmental protection, energy conservation, suitability for personalized customization, good printability and the like, can enable the printer to exert the best benefit, and is popular in the market. The UV curing technology has the key advantages of instant drying, no solvent system, firm impedance film, low energy consumption application and the like, can be well adhered to a plurality of plastic cement, fabric, plastic cement, paper, metal and other base materials, and the UV ink-jet film layer has the advantages of external durability, high glossiness, water resistance, wear resistance, good color and luster and the like.

In the existing ink-jet process, UV ink-jet flows out through a nozzle channel of a capillary tube to jet ink, and is easy to stay in the nozzle channel, so that ink is locally thickened and thickened, and the problems of frame missing, scattered dots, oblique jet or trailing and the like occur in long-time printing, thereby affecting the attractiveness of images and increasing the repeated printing cost and the maintenance cost. The reason for this is that the poor compatibility of the raw materials for manufacturing the UV ink-jet ink, the difficulty in compatibility of the high molecular weight oligomer with the monomer solvent, the poor hydrophilicity of the UV ink-jet ink, the large particle size of the ink-jet ink droplet, and the easy adsorption of the UV ink-jet macromolecules on the wall of the channel tube, further cause the local thickening and the viscosity of the ink. In the prior art, the problem is solved by adding a large amount of solvent for dilution, reducing the viscosity of ink jet and reducing the ink jet retained by a nozzle. For example, CN201610109661 discloses a UV inkjet ink which solves the problem of inkjet retention by adding a diluent and a rheological additive, but still has the problems of frame missing, dot scattering, slant spraying or tailing, etc., and does not solve the problem fundamentally. To achieve high precision image output, the particle size of the UV inkjet ink droplets needs to be precisely controlled. The particle size of the UV inkjet ink droplets is determined by the physical properties such as viscosity, surface tension, density, and temperature of the ink, and the properties such as viscosity, surface tension, and density of the ink are determined by the properties of the inkjet raw materials. Therefore, to develop a UV inkjet that can be printed for a long time without problems such as missing frames, tailing, scattering, oblique jetting, etc., it is necessary to take sufficient consideration for compatibility between the monomer and the polymer oligomer.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a solvent-free UV ink-jet for long-time continuous jet printing, which adopts a monofunctional monomer and a bifunctional monomer as active monomers, simultaneously controls the viscosity of the monomers and a high-molecular oligomer, and prepares the solvent-free UV ink-jet by stirring a high-speed dispersant and grinding the monomers and the high-molecular oligomer by a turbine type sand mill, so that the viscosity of the UV ink-jet is reduced, the fluidity of the UV ink-jet is improved, the problem of nozzle retention caused by poor compatibility of the UV ink-jet is fundamentally solved, and the technical problems of frame missing, dot scattering, oblique jet or trailing and other phenomena easily occurring in long-time printing are.

The invention is realized by the following technical scheme:

in one aspect, the invention provides a solvent-free UV ink for long-time continuous jet printing, which comprises the following components in parts by weight:

20-80 parts of monofunctional monomer, 20-60 parts of bifunctional monomer, 1-30 parts of acrylic oligomer, 1-15 parts of nano pigment, 1-20 parts of photoinitiator, 0.1-1 part of dispersant, 0.1-1 part of flatting agent, 0.1-1 part of defoaming agent and 1-25 parts of auxiliary agent.

Further, the monofunctional monomer viscosity is less than 20, specifically, the monofunctional monomer viscosity is less than 18, more specifically, the monofunctional monomer viscosity is less than 15.

Further, the monofunctional monomer is one or a combination of more than one of tetrahydrofurfuryl acrylate (THFA), Cyclic Trimethylolpropane Formal Acrylate (CTFA), ethoxyethoxyethyl acrylate (EOEOEA), 3, 5-trimethylcyclohexyl acrylate (TMCHA), Lauric Acrylate (LA), tetrahydrofurfuryl methacrylate (THFMA), Lauric Methacrylate (LMA), Glycidyl Methacrylate (GMA), cyclohexyl methacrylate (CHMA), isobornyl acrylate (IBOA), isobornyl methacrylate (IBOMA), and specifically, the monofunctional monomer is tetrahydrofurfuryl acrylate (THFA), Cyclic Trimethylolpropane Formal Acrylate (CTFA), ethoxyethoxy ethyl acrylate (EOEA), 3, 5-trimethylcyclohexyl acrylate (TMCHA), One or more of lauric acid acrylate (LA), tetrahydrofurfuryl methacrylate (THFMA), isobornyl acrylate (IBOA), isobornyl methacrylate (IBOMA) and the like, more specifically, the monofunctional monomer is one or more of tetrahydrofurfuryl acrylate (THFA), 3, 5-trimethylcyclohexyl acrylate (TMCHA), isobornyl acrylate (IBOA) and isobornyl methacrylate (IBOMA) and the like

Further, the difunctional monomer viscosity is less than 30, specifically, the difunctional monomer viscosity is less than 25, more specifically, the difunctional monomer viscosity is less than 15.

Further, the bifunctional monomer is one or a combination of more than one of 1, 6-hexanediol diacrylate (HDDA), dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), Ethylene Glycol Dimethacrylate (EGDMA), 1, 4-butanediol diacrylate (BDDA), specifically, the bifunctional monomer is one or a combination of at least two of 1, 6-hexanediol diacrylate (HDDA), dipropylene glycol diacrylate (DPGDA), Ethylene Glycol Dimethacrylate (EGDMA), 1, 4-butanediol diacrylate (BDDA), and more particularly, the bifunctional monomer is one or more of 1, 6-hexanediol diacrylate (HDDA), dipropylene glycol diacrylate (DPGDA) and 1, 4-butanediol diacrylate (BDDA).

Further, the acrylic oligomer viscosity is less than 500, specifically, the acrylic oligomer viscosity is less than 400, more specifically, the acrylic oligomer viscosity is less than 300.

Further, the acrylic oligomer is one or more of epoxy acrylate oligomer, polyurethane acrylic oligomer and polyester acrylic oligomer.

Further, the photoinitiator is one or a combination of more than one of Isopropyl Thioxanthone (ITX), 2, 4-diethyl thioxanthone (DETX), 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide (TPO), ethyl 2,4, 6-trimethylbenzoylphosphonate (TPO-L), phenylbis (2,4, 6-trimethylbenzoyl) phosphine oxide (819), 2-methyl-2- (4-morpholinyl) -1- [4- (methylthio) phenyl ] -1-propanone (907) and 2, 2-dimethoxy-2-phenylacetophenone (651), and specifically, the photoinitiator is one or a combination of Isopropyl Thioxanthone (ITX), ethyl 2,4, 6-trimethylbenzoylphosphonate (TPO-L), 2-methyl-2- (4-morpholinyl) -1- [4- (methylthio) phenyl ] -1-acetone (907) and 2, 2-dimethoxy-2-phenylacetophenone (651), and more specifically, the photoinitiator is one or more of Isopropyl Thioxanthone (ITX), ethyl 2,4, 6-trimethylbenzoylphosphonate (TPO-L) and 2-methyl-2- (4-morpholinyl) -1- [4- (methylthio) phenyl ] -1-acetone (907).

Further, the auxiliary agent is one or a combination of more than one of chlorinated modified acrylic resin, fatty alcohol-polyoxyethylene ether, modified rubber, fluorocarbon silicon modified resin and graphene.

In another aspect, the present invention provides a method for preparing a solvent-free UV inkjet for long-term continuous inkjet printing, comprising the steps of:

1) weighing 20-80 parts of monofunctional monomer, 20-60 parts of bifunctional monomer, 1-30 parts of acrylic oligomer, 1-25 parts of nano pigment, 1-20 parts of photoinitiator, 0.1-1 part of dispersant, 0.1-1 part of flatting agent, 0.1-1 part of defoaming agent and 1-25 parts of auxiliary agent;

2) adding the auxiliary agent, the dispersing agent and the nano pigment into the monofunctional monomer according to the parts by weight, adjusting the rotating speed, uniformly stirring, and then grinding by using a sand mill to prepare color paste with required fineness;

3) adding bifunctional monomers, acrylic acid oligomers, photoinitiators, flatting agents and defoaming agents into the color paste prepared in the step 2) according to parts by weight, stirring and discharging to obtain the solvent-free UV ink-jet for long-time continuous jet printing.

Further, the stirring rotation speed in the step 2) is 500-2000r/min, specifically, the stirring rotation speed in the step 2) is 1000-2000r/min, and specifically, the stirring rotation speed in the step 2) is 1500 r/min.

Further, the stirring time in step 2) is 10 minutes to 2 hours, specifically, the stirring time in step 2) is 10 minutes to 1 hour, more specifically, the stirring time in step 2) is 30 minutes.

Further, the flow rate at the time of grinding in step 2) is maintained at 0.05 to 0.5L/min, more specifically, the flow rate at the time of grinding in step 2) is maintained at 0.05 to 0.2L/min, more specifically, the flow rate at the time of grinding in step 2) is maintained at 0.1L/min.

Further, the fineness of the color paste in the step 2) is not less than 50nm of D50 and not more than 150nm of D90, specifically, the fineness of the color paste in the step 2) is not less than 40nm of D50 and not more than 100nm of D90, more specifically, the fineness of the color paste in the step 2) is not less than 30nm of D50 and not more than 80nm of D90.

Further, the stirring rotation speed in the step 3) is 1500r/min, specifically, the stirring rotation speed in the step 3) is 500 + 1000r/min, and more specifically, the stirring rotation speed in the step 3) is 800 r/min.

Further, the stirring time in step 3) is 10-60min, specifically, the stirring time in step 3) is 20-40min, and more specifically, the stirring time in step 3) is 30 min.

Compared with the prior art, the technical scheme provided by the invention has the following beneficial effects:

1) according to the invention, the low-functionality monomer and the low-viscosity acrylic acid oligomer are used as active monomer raw materials, and the characteristics of few functional groups, simple chain type and low viscosity of the low-functionality monomer are utilized to be ground together with the pigment, so that the ink jet ink drop with small particle size, low viscosity and high stability can be obtained, the viscosity and the fluidity of UV ink jet can be effectively improved, and the printing quality is stable in long-time continuous printing;

2) by adding the optimized auxiliary agent and auxiliary agent, the surface tension and the curing shrinkage rate of the ink are reduced, the penetration capacity and the curing speed of the UV ink-jet are improved, the adhesion force of the UV ink-jet and the toughness of a UV ink layer are increased, the fireproof and heat-insulating performance of the UV ink-jet is improved, and the ink is helped to penetrate to the surface of a printing stock to be penetrated, so that the UV ink-jet shows good adhesion on different materials;

3) the UV ink-jet ink is solvent-free UV ink-jet, and an organic solvent is not required to be added in the production process, so that the production cost is saved, the environmental problem caused by volatilization of the organic solvent is reduced, the UV ink-jet ink is environment-friendly, and the curing rate of the UV ink-jet ink is improved;

4) by adding the photoinitiator promoted by low energy, the illumination intensity of UV ink-jet curing is reduced, the printability of the UV ink is improved, and the UV ink-jet is suitable for printing of various materials.

Detailed Description

The following examples are intended to illustrate the invention without further limiting its scope.

Example 1

A preparation method of a solvent-free UV ink jet capable of realizing long-time continuous jet printing comprises the following steps:

1) weighing 40 parts of tetrahydrofurfuryl acrylate (THFA), 30 parts of 1, 6-hexanediol diacrylate (HDDA), 25 parts of polyurethane acrylic oligomer, 12 parts of Isopropyl Thioxanthone (ITX), 10 parts of chlorinated modified acrylic resin, 10 parts of modified rubber, 720 parts of nano C.I. pigment black, 0.5 part of polyvinylpyrrolidone, 1 part of organosilicon modified acrylate and 0.5 part of amino modified polysiloxane;

2) according to the weight parts, adding chlorinated modified acrylic resin, polyvinylpyrrolidone and nano C.I. pigment black 7 into tetrahydrofurfuryl acrylate (THFA), stirring for 30min at the rotating speed of 1500r/min, then grinding for 3 times by using a turbine type sand mill, and keeping the flow at 0.1L/min to obtain color paste with the fineness D50 being less than or equal to 30nm and the fineness D90 being less than or equal to 80 nm;

3) adding 1, 6-hexanediol diacrylate, polyurethane acrylic acid oligomer, isopropyl thioxanthone, modified rubber, organic silicon modified acrylate and amino modified polysiloxane into the color paste according to the weight parts, uniformly mixing, adjusting the rotating speed to 800r/min, stirring for 30min, and discharging to obtain the solvent-free UV ink jet.

Example 2

1) weighing 30 parts of 3,3, 5-trimethylcyclohexyl acrylate (TMCHA), 40 parts of dipropylene glycol diacrylate (DPGDA), 15 parts of epoxy acrylate oligomer, 10 parts of 2,4, 6-trimethylbenzoyl ethyl phosphonate (TPO-L), 8 parts of graphene, 12 parts of modified rubber, 715 parts of nano C.I. pigment black, 0.5 part of ammonium polyacrylate salt, 1 part of organosilicon modified acrylate and 0.5 part of amino modified polysiloxane;

2) adding graphene, ammonium polyacrylate and nano C.I. pigment black 7 into 3,3, 5-trimethylcyclohexyl acrylate (TMCHA) according to parts by weight, stirring for 30min at the rotating speed of 1500r/min, then grinding for 3 times by using a turbine type sand mill, and keeping the flow at 0.1L/min to obtain color paste with the fineness D50 being less than or equal to 30nm and the fineness D90 being less than or equal to 80 nm;

3) adding dipropylene glycol diacrylate (DPGDA), epoxy acrylate oligomer, 2,4, 6-trimethyl benzoyl ethyl phosphonate (TPO-L), modified rubber, organic silicon modified acrylate and amino modified polysiloxane into the color paste according to the weight parts, uniformly mixing, adjusting the rotating speed to be 800r/min, stirring for 30min, and discharging to obtain the solvent-free UV ink jet.

Example 3

1) weighing 35 parts of isobornyl acrylate (IBOA), 45 parts of 1, 4-butanediol diacrylate (BDDA), 10 parts of polyester acrylic oligomer, 8 parts of 2-methyl-2- (4-morpholinyl) -1- [4- (methylthio) phenyl ] -1-acetone (907), 5 parts of fatty alcohol-polyoxyethylene ether, 12 parts of modified rubber, 710 parts of nano C.I. pigment black, 0.5 part of ammonium polyacrylate salt, 1 part of organosilicon modified acrylate and 0.5 part of amino modified polysiloxane;

2) adding fatty alcohol-polyoxyethylene ether, ammonium polyacrylate and nano C.I. pigment black 7 into isobornyl acrylate (IBOA) according to parts by weight, stirring for 30min at the rotating speed of 1500r/min, then grinding for 3 times by using a turbine type sand mill, and keeping the flow at 0.1L/min to obtain color paste with the fineness D50 being less than or equal to 30nm and the fineness D90 being less than or equal to 80 nm;

3) adding 1, 4-butanediol diacrylate (BDDA), polyester acrylic oligomer, 2-methyl-2- (4-morpholinyl) -1- [4- (methylthio) phenyl ] -1-acetone (907), modified rubber, organic silicon modified acrylate and amino modified polysiloxane into the color paste according to the weight parts, uniformly mixing, adjusting the rotating speed to 800r/min, stirring for 30min, and discharging to obtain the solvent-free UV ink jet.

Comparative example 1

Trimethylolpropane triacrylate (TMPTA) was used instead of tetrahydrofurfuryl acrylate (THFA), TMP9EOTA ethoxylated trimethylolpropane triacrylate was used instead of 1, 6-hexanediol diacrylate (HDDA), and no chlorinated modified acrylic resin and modified rubber were added, and the other materials were the same, to obtain the inkjet ink of comparative example 1.

Comparative example 2

The inkjet of comparative example 2 was prepared by using trimethylolpropane triacrylate (TMPTA) instead of 3,3, 5-trimethylcyclohexyl acrylate (TMCHA), TMP9EOTA to ethoxylate trimethylolpropane triacrylate instead of dipropylene glycol diacrylate (DPGDA), and not adding graphene and modified rubber, but otherwise the same.

Comparative example 3

Trimethylolpropane triacrylate (TMPTA) was used instead of isobornyl acrylate (IBOA), TMP9EOTA was used to ethoxylate trimethylolpropane triacrylate instead of 1, 4-butanediol diacrylate (BDDA), and no fatty alcohol polyoxyethylene ether and modified rubber were added, and the rest were the same, to obtain the inkjet ink of comparative example 3.

Example 4

The UV ink jet inks prepared in examples 1 to 3 and comparative examples 1 to 3 were subjected to a test machine test, and the test results are shown in Table 1, wherein the test machine test was carried out by using an HP SCITEX FB500 printer and a Rich gloss 2513G5 printer, and the test machine test was carried out for 30 minutes, 60 minutes, 120 minutes and 180 minutes, respectively, to examine the printing quality:

example 1

Example 2

Example 3

Comparative example 1

Comparative example 2

Comparative example 3

30 minutes

OK

60 minutes

OK

1 scattered point

2 scattered points

120 minutes

OK

2 missing frame, 3 scattered points

3 missing frame, 2 scattered points

2 trailing, 3 scattered point, 1 oblique spraying

180 minutes

OK

NG

TABLE 1

Remarking: OK represents the phenomena of no missing frame, tailing, scattered points and oblique spraying, and NG represents that the total number of the bad defects exceeds 5.

As can be seen from Table 1, the UV ink-jet inks obtained in examples 1 to 3 were excellent in printing quality and free from missing frames, tailing, scattered dots and oblique jetting, while the UV ink-jet inks obtained in comparative examples 1 to 3 were poor in printing quality because the number of missing frames, tailing, scattered dots and oblique jetting was increased as the printing time became longer, and when the printing time was 120 minutes or more, the total number of defective printing defects was 5 or more.

Example 5

According to ISO2409 standard, the UV ink-jet ink prepared in examples 1-3 and comparative examples 1-3 is used for adhesion test, a hundred grids are drawn on a printed substrate by using a hundred-grid knife, the cut part is required to reach the substrate, ink scraps are cleaned by using a brush, then the hundred grids are bonded by using an adhesive tape and pulled upwards at 90 degrees, and whether the ink layer falls off or cracks is observed. Judging and grading the adhesive force: the grade 0 represents that the cut of the hundred-grid cutter is smooth and has no spalling or breakage; grade 1 represents 5% of the cut of the hundred-grid knife is peeled or broken; grade 2 represents 5-15% of the cut of the hundred-grid knife is stripped or broken; grade 3 represents 15-35% of the cut of the hundred-grid knife is stripped or broken; grade 4 represents 35-65% of the cuts of the hundred-grid knife are peeled or broken; grade 5 represents more than 65% of the cuts of the javelin knife peeled or broke, and the test results are shown in table 2.

Example 1

Example 2

Example 3

Comparative example 1

Comparative example 2

Comparative example 3

Acrylic acid

Level 0

Level 1

Level 0

Grade 3

4 stage

Polyvinyl chloride

Level 1

Level 0

4 stage

TABLE 2

As can be seen from Table 2, the adhesion of examples 1 to 3 is between 0 and 1 grade, showing excellent adhesion, and the adhesion of comparative examples 1 to 3 is between 3 and 4 grades, showing poor adhesion.

Example 6

The UV inkjet inks obtained in examples 1 to 3 and comparative examples 1 to 3 were subjected to a curing rate test, a curing shrinkage test, a surface tension test and a viscosity test, and the test results are shown in table 3.

TABLE 3

As can be seen from Table 3, examples 1 to 3 are larger than comparative examples 1 to 3 in terms of curing rate, indicating that the curing time of the present application is short; examples 1-3 were smaller than comparative examples 1-3 in terms of cure shrinkage, surface tension and viscosity, indicating that the inks prepared in examples 1-3 had good adhesion and low viscosity.

Although the invention has been described in detail hereinabove by way of general description, specific embodiments and experiments, it will be apparent to those skilled in the art that many modifications and improvements can be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. The solvent-free UV ink jet for long-time continuous jet printing is characterized by comprising the following components in parts by weight:

2. The solventless UV inkjet ink of claim 1 wherein said monofunctional monomer has a viscosity of less than 20, said difunctional monomer has a viscosity of less than 30, and said acrylic oligomer has a viscosity of less than 500.

3. The solvent-free UV inkjet according to claim 2, wherein the monofunctional monomer is one or a combination of more than one of tetrahydrofurfuryl acrylate (THFA), cyclotrimethylolpropane formal acrylate (CTFA), ethoxyethoxyethoxyethyl acrylate (EOEOEA), 3, 5-trimethylcyclohexyl acrylate (TMCHA), Lauric Acrylate (LA), tetrahydrofurfuryl methacrylate (THFMA), Lauric Methacrylate (LMA), Glycidyl Methacrylate (GMA), cyclohexyl methacrylate (CHMA), isobornyl acrylate (IBOA), isobornyl methacrylate (IBOMA).

4. The solvent-free UV inkjet according to claim 2, wherein the difunctional monomer is one or a combination of more than one of 1, 6-hexanediol diacrylate (HDDA), dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), Ethylene Glycol Dimethacrylate (EGDMA), and 1, 4-butanediol diacrylate (BDDA).

5. The solventless UV inkjet ink according to claim 2 wherein the acrylic oligomer is one or a combination of more than one of an epoxy acrylate oligomer, a polyurethane acrylic oligomer, and a polyester acrylic oligomer.

6. The solvent-free UV inkjet according to claim 2, wherein the auxiliary agent is one or a combination of more than one of chlorinated modified acrylic resin, fatty alcohol-polyoxyethylene ether, modified rubber, fluorocarbon silicon modified resin, and graphene.

7. The method of preparing a solvent-free UV inkjet according to claim 1, comprising the steps of:

8. The method for preparing the solvent-free UV inkjet according to claim 7, wherein the stirring speed in step 2) is 500-2000r/min, the stirring time is 10 minutes-2 hours, and the flow rate during grinding is maintained at 0.05-0.5L/min.

9. The preparation method of the solvent-free UV ink-jet according to claim 7, wherein the fineness of the color paste in the step 2) is D50-50 nm and D90-150 nm.

10. The method for preparing the solvent-free UV ink-jet according to claim 7, wherein the stirring speed in step 3) is 500-1500r/min, and the stirring time is 10-60 min.