CN115960492B - Oil-based inkjet ink and preparation method and application thereof - Google Patents

Abstract

The application relates to oily ink-jet ink, a preparation method and application thereof. The oily inkjet ink comprises pigment, a dispersing aid, a modified resin and a non-aqueous solvent, wherein the dispersing aid is a low-polarity high-molecular-weight dispersing aid containing pigment affinity groups, and the modified resin contains a six-membered ring structure. The oily ink-jet ink has good dispersion stability, storage stability and universality, can be used on various printing spray heads, and has better spray head moisturizing property and printing smoothness.

Description

Oil-based inkjet ink and preparation method and application thereof

Technical field

The invention relates to the field of inks, and specifically relates to a low-diffusivity oily drawing inkjet ink that can be used for engineering drawings and its preparation method and application.

Background technique

Using digital inkjet technology for blueprint printing can give full play to the high precision and high stability of the print head, ensuring that there is no difference in quality between the first and the 10,000th blueprint printed. Currently, water-based inks are mostly used for inkjet printing, but the printed patterns are not water-resistant, light-resistant, have poor migration resistance, and have poor storage properties, making them unsuitable for printing high-end documents such as engineering drawings. Compared with water-based inks, oil-based inks have the characteristics of bright colors, good water and light resistance, and high durability of printed image quality. They have a huge market in large-format and wide-format inkjet printing.

Oil-based ink can be classified into solvent ink (solvent-based ink) whose main solvent is a volatile organic solvent and oil-based ink (oil-based ink) whose main solvent is a low-volatile or non-volatile organic solvent. Solvent ink dries on the recording medium mainly through the evaporation of the organic solvent. In contrast, oil-based ink dries mainly by penetrating into the recording medium. Oil-based ink printing is more environmentally friendly. However, in related technologies, oil-based ink tends to spread laterally after printing on paper, affecting image clarity. In addition, when oil-based ink is used on inkjet printers, there are often problems such as insufficient printing smoothness, poor moisture retention of the nozzles, and one formula ink is only suitable for a certain nozzle.

Contents of the invention

In view of the shortcomings of the existing technology, the first purpose of the present invention is to provide an oil-based inkjet ink that has low diffusivity, high image definition, good dispersion stability, storage stability, and better Excellent ink printing smoothness and nozzle moisturizing properties.

The second object of the present invention is to provide a preparation method for the above-mentioned oily inkjet ink, which has simple steps and high production efficiency.

The third object of the present invention is to provide a printed object obtained by inkjet printing with the above oil-based inkjet ink. The printed object has clear lines and good water resistance and light resistance.

In order to achieve the above first object, the present invention provides an oily inkjet ink, which contains a pigment, a dispersion aid, a modified resin and a non-aqueous solvent. The dispersion aid is a low-polarity polymer containing a pigment affinity group. , the modified resin contains a six-membered ring structure.

In the above scheme, the present invention provides an oily spray ink containing a pigment, a low-polarity high molecular weight dispersion aid containing a pigment affinity group and a modified resin. It is an inkjet ink for oily drawing and can be used for Engineering drawing drawing. The invention uses low-polar high-molecular-weight dispersion aids and modified resins containing pigment affinity groups for ink, which not only improves the dispersion stability and storage stability of the ink, but also improves the gloss and image clarity of the ink. .

Specifically, the present invention uses a low-polarity, high-molecular-weight dispersion aid containing pigment affinity groups. On the one hand, the high molecular weight polymer containing pigment affinity groups has a good dispersion and stabilizing effect on pigments and can be more closely related to the pigment. The combination of pigments makes the dispersion system more stable, thereby improving the dispersion stability and storage stability of the pigments in the system. At the same time, the dispersion aid deflocculates the pigments through steric hindrance. Since the deflocculated pigment particles are very small, high-quality pigments can be obtained. gloss, and improve color intensity; on the other hand, the introduction of low-polarity polymer dispersing aids improves the dispersion of the ink without increasing the viscosity of the system, and the ink has strong permeability.

At the same time, the present invention introduces a modified resin containing a six-membered ring structure. On the one hand, it can weaken the lateral penetration of the ink on the paper, thereby inhibiting the lateral diffusion of the ink and improving the image clarity of the ink; on the other hand, the modified resin containing a six-membered ring structure can The modified resin with a ring-like structure has low polarity and has good compatibility with low-polarity and high-molecular-weight polyester dispersing aids. In oil-based ink systems with modified resins, they exist in a similar miscible agglomeration manner, causing the pigments to quickly aggregate during the application and penetration of the ink to the carrier medium, reducing the gaps in the pigment layer formed on the carrier medium, and even Gaps are generated, and the gaps are also filled with modified resin with a six-membered ring structure, thereby reducing the internal scattering of the incident light on the image without reducing the reflected light, improving the gloss of the image and achieving the sensitivity required for engineering, even if Under the bright sunlight, the lines of various thicknesses printed on the drawings can also be clearly seen.

In some embodiments of the present invention, the pigment affinity group is selected from at least one of amino, hydroxyl, nitro, carboxyl, cyano, alkenyl, alkynyl, and thiol; the low-polarity polymer is selected from polyester , at least one of polyolefins.

In the above scheme, the polyester polymer is broadly defined as a polymer obtained by the polycondensation of polyols and polybasic acids, and the polyolefin polymer can be polyethylene, polypropylene, poly1-butene, Poly-1-pentene, poly-1-hexene, poly-1-octene, poly-4-methyl-1-pentene, polybutadiene, polyisoprene or ethylene, propylene, 1-butene, 1 - A copolymer of at least one type of olefins such as pentene, 1-hexene, 1-octene, 4-methyl-1-pentene, butadiene, and isoprene. Low polarity polymers are preferably polyester polymers or flexible polyolefins. The linear flexible macromolecular chain structure has no cross-linking between molecules and relies on intermolecular van der forces and/or hydrogen bonds to attract and entangle. Under external impact, , can penetrate, overlap and entangle with the modified resin containing a six-membered ring structure in the system to improve the stability of the system. The pigment affinity groups in the molecular chain are compatible with the pigment, and can also form hydrogen bonds or other intermolecular forces with each other, creating high interactions between the molecular chains, thereby stabilizing the pigment particles.

In some embodiments of the present invention, the dispersion aid is selected from HP1024, HP1032, HP1058, HP1059, HP1362, HP1453, HP1476, HP1477, HP1478, HP1521, BYK-JET9142, BYK9131, BYK2200, BYK9151, KYC-919, KYC- At least one of 918 and KYC-970.

In the above scheme, the dispersing aid is selected from the above-mentioned dispersing aid brands, and the above-mentioned dispersing agents are low-polarity polymers containing pigment affinity groups. These dispersants are commercially available and the raw materials are readily available.

In some embodiments of the present invention, the modified resin is selected from at least one of petroleum resin, polyketone resin, and hydrogenated rosin ester.

In the above scheme, the modified resin can be petroleum resin, polyketone resin and/or hydrogenated rosin ester containing six-membered carbon rings. On the one hand, this type of resin has good adhesion, wear resistance, weather resistance and Water resistance, fast drying and high solidity. Adding this type of resin to the ink system can achieve adhesion, color loading, quick drying, brightening, and improve printing performance. On the other hand, this type of resin has the same The broad compatibility or good solubility of other components in the ink system protects the pigment from photo-oxidative degradation, reduces the fading or discoloration of the ink, and improves the gloss and usability of the printed object.

In some embodiments of the present invention, the non-aqueous solvent includes at least one of low-volatile or non-volatile fatty acid esters and low-volatile or non-volatile oils.

In the above scheme, the non-aqueous solvent uses low volatility or non-volatile oily solvent. On the one hand, this type of non-aqueous solvent is a solvent carrier with high boiling point, low viscosity and low molecular weight. For penetration drying ink, it relies on These properties of them can adjust the rheological properties of the ink system, allowing the ink to successfully penetrate into the carrier medium, thereby accelerating its fixation and drying on the carrier medium. On the other hand, the volatility of this type of non-aqueous solvent is extremely low or even non-volatile, which greatly protects the health and safety of operators and environmental protection, allowing oil-based inks to be used in indoor office environments.

In some embodiments of the present invention, the low-volatile or non-volatile fatty acid ester is cyclohexane 1,2-dicarboxylic acid diisononyl ester, tributyl citrate, isopropyl palmitate, isopropyl palmitate. At least one of octyl ester, isononyl isononate, soybean oil methyl ester, and soybean oil isobutyl ester.

In the above scheme, select cyclohexane 1,2-dicarboxylic acid diisononyl ester, tributyl citrate, isopropyl palmitate, isooctyl palmitate, isononyl isononanoate, and soybean oil methyl ester. , soybean oil isobutyl ester as a non-aqueous solvent, the ink system is more stable and reliable.

In some embodiments of the present invention, the low-volatile or non-volatile oil includes at least one of mineral oil and silicone oil.

In the above solution, the mineral oil can be refined mineral oil. Mineral oil has strong permeability and can make the ink dry quickly. Silicone oil can be low molecular weight silicone oil, which can form an isolation layer on the paper. When the ink penetrates to a certain level, it will not continue to penetrate, causing the pattern to fade.

In some embodiments of the invention, the mineral oil is a C20-C32 isoparaffin.

In the above scheme, C20-C32 isoparaffin has good permeability.

In some embodiments of the invention, the silicone oil is a linear alkyl polysiloxane.

In the above scheme, linear alkyl polysiloxane such as dimethylsiloxane has good barrier properties.

In some embodiments of the invention, the non-aqueous solvent contains low-volatile or non-volatile fatty acid esters and low-volatile or non-volatile oils.

In the above solution, the non-aqueous solvent contains both low-volatile or non-volatile fatty acid esters and low-volatile or non-volatile oils, taking into account the stability and permeability or barrier properties of the ink.

In some embodiments of the present invention, the non-aqueous solvent contains fatty acid esters, mineral oil and silicone oil.

In the above solution, fatty acid esters, refined mineral oil and silicone oil are used as non-aqueous solvents, which can dissolve other components in the ink well; the ink has a certain permeability, allowing the substrate to dry quickly, and will not fade.

In some embodiments of the present invention, the pigment includes at least one of carbon black and organic pigment.

In the above solution, the pigment has good dispersion in non-aqueous solvents, and ensures excellent color performance and high tinting strength of the ink, with a wide chromatogram.

In some embodiments of the present invention, the organic pigment is selected from at least one of disazo pigments, phenol AS pigments, and phthalocyanine blue.

In the above solution, the pigment can be selected from carbon black or organic pigments, and the dosage can be adjusted to give the ink different colors, color concentrations, light resistance, and water resistance.

In some embodiments of the present invention, the oil-based inkjet ink contains 1% to 15% pigment, 2% to 10% dispersion aid, 2% to 15% modified resin and the balance non-aqueous solvent.

In the above solution, the ink has good performance, the pigment is stably dispersed, the ink is in a stable moisturizing state, and the ink viscosity can realize its adaptability to a variety of nozzles. Under this combination, the printer nozzle is turned on after 7 days of standby, and the ink It can print continuously without clogging the nozzle and has good fluency.

In some embodiments of the present invention, the oil-based inkjet ink contains 1% to 15% pigment, 2% to 10% dispersion aid, 2% to 15% modified resin, 10% to 30% low volatility volatile or non-volatile fatty acid esters and the balance low-volatile or non-volatile oils. In some embodiments of the present invention, the oil-based inkjet ink contains 1% to 15% pigment, 2% to 10% dispersion aid, 2% to 15% modified resin, 10% to 30% low volatility Stable or non-volatile fatty acid esters, 3% to 15% silicone oil and the balance mineral oil.

Among the above solutions, the ink has the best overall performance and good printing effect.

In some embodiments of the present invention, the oil-based inkjet ink has a viscosity of 8 cps to 15 cps at 25°C.

In the above solution, the viscosity of the oil-based inkjet ink is within the above range, and can be applied to a variety of nozzles and has high versatility.

In some embodiments of the present invention, the oil inkjet ink has a surface tension of 20 mN/m to 28 mN/m.

In the above solution, the surface tension of the oily inkjet ink is within the above range, enabling the inkjet printer to eject standard ink droplets.

In some embodiments of the present invention, the particle size of the oily inkjet ink is D50≤350 and D99<500.

In the above solution, the particle size of the particle dispersion in the ink is small, it is not easy to block the nozzle, and the gloss and color intensity can be improved.

In order to achieve the second object of the present invention, the present invention provides a method for preparing the above-mentioned oily inkjet ink, which includes mixing the pigment, the dispersion aid and the first part of the non-aqueous solvent, and then adding the modified resin and the remaining second part of the non-aqueous solvent. The water-based solvent is then mixed to obtain oil-based inkjet ink.

In the above scheme, this application adopts the method of first mixing the pigment, dispersion aid and the first part of the non-aqueous solvent, first adding the modified resin and mixing the remaining second part of the non-aqueous solvent, which is beneficial to the pigment dispersion more uniformly, and the preparation method The steps are simple and the production efficiency is high.

In some embodiments of the present invention, the first part of the non-aqueous solvent is mineral oil, and the second part of the non-aqueous solvent is fatty acid ester and silicone oil.

In the above solution, the pigment, dispersion aid and mineral oil are first mixed, and then the modified resin is mixed with fatty acid ester and silicone oil, which can make the dispersion aid better disperse the pigment.

In some embodiments of the present invention, mixing the pigment, the dispersion aid and the first part of the non-aqueous solvent includes grinding and dispersing the pigment, the dispersion aid and the first part of the non-aqueous solvent.

In the above solution, the pigments and dispersion aids are dispersed more evenly through grinding.

In some embodiments of the present invention, adding the modified resin and the remaining second part of the non-aqueous solvent and then mixing includes adding the modified resin and the remaining second part of the non-aqueous solvent and then stirring evenly.

In the above scheme, the secondary mixing uses stirring to disperse the raw materials, and the oil-based inkjet ink can be obtained.

In order to achieve the third object of the present invention, the present invention provides a printed object, which is a printed object formed with a printing surface through inkjet printing, and the printing surface is an oily inkjet ink or an oily inkjet ink according to any of the above solutions. The printing surface obtained by inkjet printing with the oil-based inkjet ink prepared by the preparation method described in any of the above solutions.

In the above aspect, the present invention provides a printed object obtained by inkjet printing using the oily inkjet ink of the present invention.

In some embodiments of the present invention, the printing surface is at least one of blue, white, yellow, and brown.

In the above solution, the appropriate ink color can be selected according to the actual engineering drawing printing needs, and matched with the printing carrier to obtain printing lines of the required color.

Compared with the existing technology, the present invention can achieve the following beneficial effects:

(1) The oil-based inkjet ink of the present invention is a low-diffusivity oil-based drawing inkjet ink with low viscosity and uniform particle size distribution. Its viscosity is between 8.0cps and 15.0cps and can be adjusted. The surface tension is 20～28mN/m, particle size D50≤350, D99<500, has good dispersion stability and storage stability, can be well matched with various nozzle printers and work normally, and can be stored for a long time;

(2) The present invention develops a low-diffusivity oil-based drawing and painting inkjet ink, which has low diffusivity and good diffusion inhibition, realizes high-quality drawing and painting of oil-based inkjet ink on engineering drawings, and improves the image of printed matter. The quality of the ink prevents fading, ink accumulation, ink melting, wrinkling, edge bleeding, etc. on the engineering paper. At the same time, the resulting ink has the sensitivity required for engineering, and can print lines of various thicknesses on the engineering drawings. It can be clearly seen under sunlight and can also be used directly for copying, and the resulting copy will be exactly the same as the original;

(3) The low-diffusion oil-based drawing inkjet ink of the present invention has wide versatility and breaks through the limitation of matching one ink formula to one printing nozzle. The obtained oil-based inkjet ink can be used in printing nozzles such as Toshiba, Konica, and Seiko. It has good spray stability, standby performance and nozzle moisturizing properties;

(4) The low-diffusivity oil-based ink of the present invention has the performance to draw mechanical, electronic, civil engineering, mining, geological survey and other engineering drawings on various engineering drawings. It is especially suitable for integrating high-speed on various engineering drawings. Printing machine drawing and painting various precision engineering graphics.

Detailed ways

The present invention provides a low-diffusivity oily drawing inkjet ink and its preparation method and application. In order to make the purpose, technical solution and effect of the present invention clearer and clearer, the present invention will be further described in detail below through specific examples. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

In some embodiments of the present invention, the present invention provides an oil-based inkjet ink, which is mainly composed of pigments, dispersion aids, modified resins and non-aqueous solvents. It has low diffusivity and is suitable for oil-based drawings.

In some embodiments of the present invention, by weight percentage, the oil-based inkjet ink includes 1% to 15% pigment, 2% to 10% dispersion aid, 2% to 15% modified resin, and the balance is non-aqueous. Solvent. In some embodiments of the present invention, by weight percentage, the oil-based inkjet ink includes 1% to 15% pigment, 2% to 10% dispersion aid, 2% to 15% modified resin, 10% to 30% Fatty acid ester, 3% to 15% modified silicone oil and the balance refined mineral oil. Wherein, the weight percentage of the pigment can be, for example, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% Or 15%; the weight percentage of the dispersion aid can be, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10%; the weight percentage of the modified resin can be, for example, 2 %, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% or 15%; the weight percentage of fatty acid ester can be, for example 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26% , 27%, 28%, 29% or 30%; the weight percentage of modified silicone oil can be, for example, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12 %, 13%, 14% or 15%.

In some embodiments of the present invention, the pigment is one or more of disazo pigments, phenol AS pigments, phthalocyanine blue, and carbon black. The pigment can be flexibly selected according to the color of the inkjet ink. There is no special limitation on the source of the pigment, and it can be prepared using preparation methods well known to those skilled in the art or commercially available products.

In some embodiments of the present invention, the dispersing aid is a low-polarity, high-molecular-weight polyester polymer. In some embodiments, examples include HP1024, HP1032, HP1058, HP1059, HP1362, HP1453, HP1476, HP1477, HP1478, HP1521, and BYK-JET9142, BYK9131, BYK2200, BYK9151 of Germany's BYK, and KYC-919, KYC-918, and KYC-970 of Keying Chemical.

In some embodiments of the present invention, the modified resin is selected from one or more of petroleum resin, polyketone resin, and hydrogenated rosin ester. In some embodiments, the petroleum resin is C9 petroleum resin. The source is not particularly limited and can be prepared using preparation methods well known to those skilled in the art or commercially available products; examples of polyketone resins include CT-A81 from Jinan Changtai Chemical Co., Ltd., and CT-A81 from Anqing Hongyu Chemical Co., Ltd. BK-515; Examples of hydrogenated rosin esters include fully hydrogenated rosin, hydrogenated galbanum rosin, etc. Specifically, they can be KE311, KE604, KR610 from Arakawa, Japan, or Foral AX-E from Eastman Company in the United States.

In some embodiments of the present invention, the fatty acid ester is cyclohexane 1,2-dicarboxylic acid diisononyl ester, tributyl citrate, isopropyl palmitate, isooctyl palmitate, isononanoic acid One or more of nonyl ester, soybean oil methyl ester, and soybean oil isobutyl ester, there is no special limit on the source of the fatty acid ester, and it can be prepared using preparation methods well known to those skilled in the art or commercially available products.

In some embodiments of the present invention, the refined mineral oil is C20-C32 isoparaffin. There is no special limit on the source of the refined mineral oil. It can be prepared using preparation methods well known to those skilled in the art or commercially available products.

In some embodiments of the present invention, the modified silicone oil is a linear low molecular weight silyl compound. As the modified silicone oil, various organic groups can be introduced into a part of the silicon atoms of the chain dimethyl silicone oil. And the silicone oil obtained. As the modified silicone oil, it is preferable that all silicon atoms are bonded only to either carbon atoms or oxygen atoms of siloxane bonds. As the modified silicone oil, it is preferable that its constituent atoms consist only of silicon atoms, carbon atoms, oxygen atoms, and hydrogen atoms. As modified silicone oil, dimethyl silicone oil can be cited. The source of dimethyl silicone oil is not particularly limited. It can be prepared using preparation methods well known to those skilled in the art or commercially available products.

The technical solution of the present invention will be further described below in conjunction with the examples and comparative examples. Embodiments 1 to 5 and Comparative Examples 1 to 5 of the low-diffusion oily drawing inkjet ink of the present invention are prepared according to the raw material composition shown in Table 1. In the following examples and comparative examples, unless otherwise specified, the contents are in mass percentage.

Table 1 Examples and Comparative Examples Raw Material Composition

The difference between Examples 1 to 5 and Comparative Examples 1 to 5 is that when preparing the oil-based inks in Comparative Examples 1 to 5, Comparative Example 1 does not contain a dispersing aid, and the dispersing aids in Comparative Examples 2 and 3 Change to commonly used dispersing aids for oil-based inkjet inks. Comparative Example 2 uses BASF's modified polyurethane polymer EFCA 4010. Comparative Example 3 uses BASF's modified polyacrylate PA4550. In Comparative Example 4, no six-membered cyclic polymer is added. Structure modified resin, in Comparative Example 5, polyurethane resin commonly used in oil-based inks (HP1308 from Anshan Huihong New Materials Chemical Co., Ltd.) was used instead of modified resin containing a six-membered ring structure.

The same kind of pigment is used in the above-mentioned Examples 1 to 5 and Comparative Examples 1 to 5. Changing the type of pigment has little effect on the properties and parameters such as viscosity, surface tension, and particle size of the ink. Different colors of ink can be obtained by changing the type of pigment.

The preparation methods of the oil-based inkjet inks in the above-mentioned Examples 1 to 5 and Comparative Examples 1 to 5 are roughly the same, and both include the following steps: add pigments and dispersion aids in proportion to mineral oil, grind and add modification in proportion Resin, fatty acid ester and modified silicone oil are stirred evenly to obtain oil-based inkjet ink. When the corresponding component is not included in the comparative example, the corresponding component in the above steps is omitted.

Test example 1

Take the oil-based inkjet inks prepared in Examples 1 to 5 and Comparative Examples 1 to 5 and test their particle size, viscosity and surface tension at 25°C and after aging at 60°C for 7 days respectively. The test results are shown in Table 2 below. The viscosity of the oily inkjet inks of Examples 1 to 5 at 25°C is 8.0cps to 15.0cps, and the surface tension is 20.0mN/m to 28.0mN/m; the ink is aged at 60°C for 7 days, the change in particle size before and after is small, and the ink has good stability; if left at room temperature for 1 year, no stratification, sedimentation, flocculation, etc. will occur.

Table 2 Particle size, viscosity and surface tension of Examples and Comparative Examples aged at 25°C and 60°C for 7 days

Test example 2

The oily inkjet inks prepared in Examples 1 to 5 and Comparative Examples 1 to 5 were filtered with a 1.0 micron glass fiber membrane and qualitative filter paper, and then printed on an integrated speed printing machine equipped with a Toshiba nozzle.

1) Installed performance test

Fill 4 ink cartridges with ink (i.e. repeat the test four times). After installing the machine, check the nozzles directly to see if there is any disconnection. If there is 0 to 1 disconnection in 4 tests, it is qualified, and if there is 2 to 4 disconnections, it is unqualified.

2) Printing fluency test

Take 1000mL of ink and pour it into the integrated speed printing machine with Konica nozzle, and continuously print 100% full-width monochrome blocks on A4 paper media for at least 1000 pages. Observe the printing status of the ink and record the number of ink break holes. Judgment criteria: A. Smooth printing, 1,000 pages of continuous printing, no broken holes, no ink breaks, good performance, and can fully meet actual use; B. Broken holes will appear during the printing process, cleaning them once will return to normal, and they will appear after 1,000 pages of continuous printing. The above situation does not occur more than twice, which can barely meet the actual use; C. serious hole breakage and ink breakage occur during the printing process, which does not meet the actual use.

3) Standby performance test

After the above printing test is completed, under the conditions of ambient temperature of 18-30°C and humidity of 50-80%, turn off the inkjet standby for 24 hours and then continue printing to test the mesh status. Judgment: It is good if the broken holes are less than or equal to 2 holes after 24 hours of standby, and it is bad if the broken holes are >2 holes after 24 hours of standby.

The test results are shown in Table 3.

Table 3 Examples and Comparative Examples Printing Test Results

Test example 3

The oily inkjet inks prepared in Examples 1 to 5 and Comparative Examples 1 to 5 were filtered with 1.0 micron glass fiber membrane and qualitative filter paper, and then printed on onepass printers equipped with Toshiba nozzles, Konica 1024i nozzles, and Seiko 1020 nozzles respectively. Above, use ordinary A4 paper to conduct a nozzle adaptability test: conduct the installation performance test, printing fluency test and standby performance test in application example 2 of the present invention on each nozzle.

Judgment criteria: When the installed performance is qualified, the printing fluency test is A or B, and the standby performance test is good, the nozzle adaptability is OK, otherwise NG.

Table 4 Nozzle adaptability test for Examples and Comparative Examples

Toshiba nozzle Konica 1024i printhead Seiko 1020 nozzle Example 1 OK OK OK Example 2 OK OK OK Example 3 OK OK OK Example 4 OK OK OK Example 5 OK OK OK Comparative example 1 NG NG NG Comparative example 2 NG NG NG Comparative example 3 NG NG NG Comparative example 4 NG NG NG Comparative example 5 NG NG NG

Test example 4

After filtering the oily inkjet inks prepared in Examples 1 to 5 and Comparative Examples 1 to 5 of the present invention with 1.0 micron glass fiber membrane and qualitative filter paper, the blueprint paper and A4 were filtered on a onepass machine equipped with a Konica 1024i nozzle and cartons and other carrier media for printing. Test the relevant performance of the printed matter.

(1) Color density: In the color presentation of printed matter, it is an important parameter and has a certain impact on the color presentation. Use a color inkjet printer to print the CMYK four-color color block, and use an X-Rite reflection density meter to measure it. The greater the solid density, the brighter the surface color of the printed matter and the more vivid and realistic the printed matter will be.

(2) Ink dot diffusion: characterized by ink dot roundness. The calculation formula for the roundness of the ink dot is: (where A is the area of the ink dot; P is the circumference of the ink dot), roundness (RD) = 4πA/P ² . The closer the value is to 1, the better the ink dot imaging is, indicating that the paper pattern does not have diffusion, penetration, etc. When the ink dot roundness value is less than 1, it means that the ink dot imaging is incomplete; when the ink dot roundness value is greater than 1, it is considered that the ink dots have spread to varying degrees.

Print CMYK four-color ink dots with roundness and diameter of 1mm. Image analysis software is then used to measure and calculate dot roundness.

(3) Line diffusion: Print CMYK four-color lines with a width of 0.5mm. Use a microphotographer to take a picture of the image magnified 1.5 times according to the scale, then measure the line width, and finally take the average value. Line diffusion is recorded as a percentage of line diffusion, with values less than 3% rated as Class A, 3% to 5% rated as Class B, and values greater than 5% rated as Class C. Among them, line diffusion percentage=[(measured value-0.5)/0.5]*100%

(4) Water resistance: Take the artworks of Examples 1 to 5 and Comparative Examples 1 to 5 printed on blueprint paper, A4 and cartons, place them in deionized water for 30 minutes, take them out, and dry them naturally at room temperature as the experimental group , take the artwork that has not been soaked in deionized water as the control group. Then use a spectrometer to measure the color properties and compare the color difference (ΔE) of the artwork before and after soaking in water. Among them, the smaller the ΔE value obtained after the water resistance test, the smaller the degree of fading of the ink, and the better the water resistance of the ink.

(6) Light resistance: Print the inks of Examples 1 to 5 and Comparative Examples 1 to 5 on blueprint paper to form an all-red artwork. After testing the color properties of the initially printed all-red artwork, use Microsol's simple The lighting machine conducts lighting experiments on all-red artwork. The lighting time is 16 hours, which is equivalent to three and a half months of normal sunshine time (10 hours of sunlight a day). After 16 hours, the color properties were measured using a spectrometer and the color difference values (ΔE) before and after irradiation were compared. Among them, the smaller the ΔE value obtained after the light test, the smaller the degree of fading of the ink, and the better the light resistance of the ink.

Table 5 Relevant performance of printed matter of Examples and Comparative Examples

color density Ink dot roundness Line spread percentage water resistance Lightfastness Example 1 2.35 1.01 A 1.7 31 Example 2 2.10 1.02 A 1.5 27 Example 3 2.03 0.99 A 2.1 35 Example 4 2.05 1.01 A 2.1 twenty four Example 5 2.04 0.98 A 1.5 33 Comparative example 1 2.36 1.07 B - - Comparative example 2 2.34 0.91 B - - Comparative example 3 2.35 1.04 A - - Comparative example 4 2.33 1.98 C - - Comparative example 5 2.34 1.24 C - -

Note: “-” in the table indicates untested items.

It can be seen from the above that by adding dispersion aids and modified resins to the inks of Examples 1 to 5 of the present invention, compared with Comparative Examples 1 to 5, the inks of Examples 1 to 5 of the present invention have a more stable dispersion effect and a better Best printing effect, nozzle adaptability and practicality.

Finally, it should be emphasized that the above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims (15)

1. An oily inkjet ink, characterized in that it is composed of a pigment, a dispersion aid, a modified resin and a non-aqueous solvent. The dispersion aid is a low-polarity polymer containing a pigment affinity group, and the pigment The affinity group is selected from at least one of amino, hydroxyl, nitro, carboxyl, cyano, alkenyl, alkynyl, and mercapto groups; the low-polarity polymer is selected from at least one of polyester and polyolefin. ; The modified resin is selected from at least one selected from petroleum resin, polyketone resin, and hydrogenated rosin ester; By weight percentage, the oily inkjet ink contains 1% to 15% of the pigment, 2% to 10% of the dispersion aid, 2% to 15% of the modified resin and the balance of the The non-aqueous solvent; the non-aqueous solvent contains low-volatile or non-volatile fatty acid esters and low-volatile or non-volatile oils; The oily inkjet ink has a viscosity of 8cps to 15cps at 25°C; the oily inkjet ink has a particle size of D50≤350nm and D99<500nm. 2. A kind of oily inkjet ink according to claim 1, characterized in that the low-volatile or non-volatile fatty acid ester is cyclohexane 1,2-dicarboxylic acid diisononyl ester, triscitrate At least one of butyl ester, isopropyl palmitate, isooctyl palmitate, isononyl isononanoate, soybean oil methyl ester, and soybean oil isobutyl ester. 3. An oily inkjet ink according to claim 1, characterized in that the low-volatile or non-volatile oil includes at least one of mineral oil and silicone oil; the mineral oil is a C20-C32 isochain. Alkanes; the silicone oil is linear alkyl polysiloxane. 4. An oil-based inkjet ink according to claim 1, characterized in that the non-aqueous solvent contains fatty acid esters, refined mineral oil and silicone oil. 5. An oil-based inkjet ink according to any one of claims 1 to 4, characterized in that the pigment includes at least one of carbon black and organic pigment. 6. An oil-based inkjet ink according to claim 5, characterized in that the organic pigment is selected from at least one of disazo pigments, phenol AS pigments, and phthalocyanine blue. 7. An oily inkjet ink according to any one of claims 1 to 4, characterized in that, by weight percentage, the oily inkjet ink contains 1% to 15% of the pigment, 2% to 2% by weight. 10% of the dispersion aid, 2% to 15% of the modified resin, 10% to 30% of low-volatile or non-volatile fatty acid esters and the balance of low-volatile or non-volatile oil. 8. An oily inkjet ink according to any one of claims 1 to 4, characterized in that the oily inkjet ink contains 1% to 15% of the pigment, 2% to 10% of the Dispersing aid, 2% to 15% of the modified resin, 10% to 30% of low-volatile or non-volatile fatty acid esters, 3% to 15% of silicone oil and the balance of mineral oil. 9. An oily inkjet ink according to any one of claims 1 to 4, characterized in that the surface tension of the oily inkjet ink is 20mN/m to 28mN/m. 10. The preparation method of an oily inkjet ink according to any one of claims 1 to 9, characterized in that it includes mixing the pigment, the dispersion aid and the first part of the non-aqueous solvent, and then adding The modified resin and the remaining second part of the non-aqueous solvent are then mixed to obtain the oily inkjet ink. 11. The preparation method according to claim 10, characterized in that the non-aqueous solvent in the first part is mineral oil, and the non-aqueous solvent in the second part is fatty acid ester and silicone oil. 12. The preparation method according to claim 10, characterized in that mixing the pigment, the dispersion aid and the first part of the non-aqueous solvent includes mixing the pigment, the dispersion aid and the first part of the non-aqueous solvent. Grind and disperse with non-aqueous solvent. 13. The preparation method according to claim 10, characterized in that adding the modified resin and the remaining second part of the non-aqueous solvent and then mixing includes adding the modified resin and the remaining second part of the non-aqueous solvent. Add the water-based solvent and stir evenly. 14. A printed object having a printing surface formed by inkjet printing, characterized in that the printing surface is an oily inkjet ink according to any one of claims 1 to 9 or an oily inkjet ink according to any one of claims 1 to 9. The printing surface obtained by inkjet printing with the oil-based inkjet ink prepared by the preparation method according to any one of claims 10 to 13. 15. The printed object according to claim 14, characterized in that the printing surface is at least one of blue, white, yellow, and brown.