Quick-dry low-odor offset printing ink and preparation method thereof

Abstract

The invention discloses quick-dry low-odor offset printing ink and a preparation method thereof. The quick-drying low-odor offset printing ink is prepared from the following raw materials in parts by weight: 15 to 30 parts of pigments in various colors, 25 to 35 parts of specific modified resin, 3 to 10 parts of extender pigment, 5 to 10 parts of quick-drying alkyd resin, 10 to 20 parts of epoxy linseed oil, 5 to 10 parts of mineral oil, 0.2 to 5 parts of zinc isoocatanoate, 0.2 to 5 parts of iron isoocatanoate and 0.2 to 5 parts of cerium isoocatanoate. According to the invention, the drying principle of the ink is thoroughly changed and innovated, a technical route mainly based on absorptive drying is adopted to replace a traditional drying mode mainly based on oxidation drying, and the ink is prepared through a specific raw material ratio and a preparation process. The prepared quick-dry low-odor offset printing ink has excellent performance characteristics and printing effects such as low odor and quick drying, keeps good fluidity and stability, and is suitable for large-scale industrial production.

Description

Technical Field

[0001] The present invention relates to the technical field of printing inks, and particularly to a quick-drying low-odor offset printing ink and a preparation method thereof. Background Art

[0002] Offset printing ink is one of the commonly used ink types in the printing industry. Characteristics such as the odor, drying speed, color vividness, adhesion, and abrasion resistance of the ink are particularly important and directly affect the printing quality and production efficiency. With the improvement of living standards, people's environmental protection requirements for printed books, newspapers, and periodicals have become increasingly strict. There was once a case in Guangzhou where a batch of printed textbooks had to be recalled due to excessive odor.

[0003] However, the current single-sheet offset printing ink generally has a serious odor and can no longer meet the market demand. The ink odor mainly comes from two aspects: one is that during the drying process, due to the use of Co, Mn series metal driers, these driers can play a good role in promoting the oxidation reaction, but at the same time, it will also cause peroxidation of the ink during the drying process, and finally decompose to produce a certain amount of aldehyde and ketone gases. These gases have a strong pungent odor, such as hexanal or n-hexanal. The other is that in order to enhance the initial drying performance and fluidity of the ink, some substances with strong volatility are used in the ink, such as methylated soybean oil. Methylated soybean oil has a strong pungent odor and gradually volatilizes after printing, which is also an important reason affecting the ink odor.

[0004] Therefore, the present invention provides a quick-drying low-odor offset printing ink with low odor and fast drying and a preparation method thereof to improve the performance and printing effect of the ink. Summary of the Invention

[0005] The purpose of the present invention is to provide a quick-drying low-odor offset printing ink and a preparation method thereof to solve the problems raised in the above background art. To achieve the above purpose, the present invention provides the following technical solutions: In the first aspect of the present invention, a quick-drying low-odor offset printing ink is provided, which comprises the following raw materials in parts by weight: 15 - 30 parts of various color pigments, 25 - 35 parts of a specific modified resin, 3 - 10 parts of extender pigments, 5 - 10 parts of a quick-drying alkyd resin, 10 - 20 parts of epoxy linseed oil, 5 - 10 parts of mineral oil, 0.2 - 5 parts of zinc isooctanoate, 0.2 - 5 parts of iron isooctanoate, 0.2 - 5 parts of cerium isooctanoate, and 0 - 5 parts of other additives.

[0006] Preferably, the solubility of the specific modified resin is 3 - 5, and the acid value ≤ 10.

[0007] Preferably, the specific modified resin is made from the following raw materials: phenolic modified resin, polyurethane resin, mineral oil, vegetable oil, methylated soybean oil, and aluminum diisopropoxyacetoacetate.

[0008] Preferably, the molecular formula of the specific modified resin is: (C15H16O2·C3H8O3·CH2O·W99)x.

[0009] Preferably, the viscosity of the specific modified resin at 25 °C is 5000 - 6000 mPa·s.

[0010] Preferably, the fast-drying alkyd resin is made from the following raw materials: linseed oil, glycerol, diethylene glycol, lithium hydroxide, phthalic anhydride, maleic anhydride, and hydroquinone.

[0011] Preferably, the raw materials of the quick-drying low-odor offset printing ink further include plant-extracted fragrant oil.

[0012] The second aspect of the present invention provides a method for preparing a quick-drying low-odor offset printing ink, comprising the following steps: A1. Wet the various color pigments and extender pigments with deionized water; A2. Use the specific modified resin and the fast-drying alkyd resin to displace the water at a certain temperature; A3. Stir under negative pressure at 150 °C for 6 hours to obtain a semi-finished product for producing the ink; A4. Grind the semi-finished product until the fineness reaches the specified specification; A5. Add zinc isooctanoate, iron isooctanoate, cerium isooctanoate, and other additives, and use mineral oil to adjust the product specifications to the specified range to obtain the finished ink.

[0013] Preferably, the preparation method of the specific modified resin comprises the following steps: B1. Dissolve the specified phenolic modified resin and polyurethane resin with a certain weight portion of mineral oil and vegetable oil at 180 °C; B2. Add methyl esterified soybean oil to adjust the viscosity of the diluted resin to the specified range; B3. Cool down to 110 °C and add aluminum diisopropoxyacetoacetate; B4. Under the condition of constant temperature of 110 °C, continue the reaction until the viscosity reaches the specified viscosity.

[0014] Preferably, the preparation method of the fast-drying alkyd resin comprises the following steps: C1. Mix a certain weight portion of linseed oil, glycerol, diethylene glycol, and lithium hydroxide, and under an oxygen-free environment, heat up to 240 °C and keep it at a constant temperature for 2 hours; C2. Cool down to 160 °C and add phthalic anhydride, maleic anhydride, and hydroquinone; C3. Heat up to 230 °C and keep it at a constant temperature for 2 hours; C4. Heat up to 240 °C and keep it at a constant temperature until the viscosity reaches the specified range.

[0015] The beneficial effects of the present invention are as follows: The present invention makes a complete change and innovation in the drying principle of the ink. It adopts a technical route mainly based on absorptive drying to replace the traditional drying mode mainly based on oxidative drying. Through specific raw material ratios and preparation processes, the prepared quick-drying and low-odor offset printing ink has excellent performance characteristics and printing effects such as low odor and fast drying, while maintaining good fluidity and stability, and is suitable for large-scale industrial production. Detailed implementation manners

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0017] It should also be understood that the terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms.

[0018] It should be further understood that the term " / and" as used in the specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0019] The quick-drying and low-odor offset printing ink of the present invention is an innovative product that makes a complete change in the drying principle. It adopts a technical route mainly based on absorptive drying to replace the traditional drying mode mainly based on oxidative drying, making the quick-drying and low-odor offset printing ink have characteristics such as low odor and fast drying. Its main raw materials include the following parts by weight: (1) 15 - 30 parts of various color pigments, which are used to provide the color of the ink and meet the printing color requirements.

[0020] (2) 25 - 35 parts of a specific modified resin, whose main molecular formula is: (C15H16O2·C3H8O3·CH2O·W99)x; In the present invention, a phenolic aldehyde modified resin and a polyurethane resin are used to produce a binder, which is combined with mineral oil, vegetable oil, methyl esterified soybean oil and aluminum diisopropoxyacetoacetate to make a specific modified resin with a fast initial drying speed. The viscosity of this specific modified resin at an ambient temperature of 25°C is 5000 - 6000 mPa·s, and it has the advantages of low solubility (solubility is 3 - 5) and low acid value (acid value ≤ 10), enabling the ink to have the ability to complete absorption drying quickly, and effectively improving the initial drying performance and drying performance of the ink.

[0021] (3) 3 - 10 parts of extender pigment, which is used to adjust the consistency and fluidity of the ink, and improve the physical properties and printing suitability of the ink.

[0022] (4) 5 - 10 parts of a fast-drying alkyd resin. In the present invention, a fast-drying alkyd resin with a low acid value and high solubility is adopted. It is made with linseed oil as the base material, combined with glycerol, diethylene glycol, lithium hydroxide, phthalic anhydride, maleic anhydride and hydroquinone. Since linseed oil has a large number of unsaturated bonds and relatively strong oxidation-reduction properties, for an alkyd resin based on linseed oil, due to its relatively large molecular weight, it only needs a small number of sites to undergo cross-linking reactions to form a film; therefore, the alkyd resin based on linseed oil has a stronger advantage in terms of drying compared to the alkyd resin based on soybean oil, realizing a drying mode where the ink uses absorption drying instead of oxidative film-forming drying; making the drying performance of this fast-drying alkyd resin shorten the drying time by 50% compared to the commonly used alkyd resins on the market, accelerating the drying process of the ink, and improving the drying performance and printing efficiency of the ink.

[0023] (5) 10 - 20 parts of epoxy linseed oil. In the present invention, epoxy linseed oil is used to replace traditional methyl esterified soybean oil and soybean oil. Compared with methyl esterified soybean oil, epoxy linseed oil is almost odorless and can prevent the generation of odors; at the same time, the initial drying performance of epoxy linseed oil is similar to that of methyl esterified soybean oil and better than that of soybean oil; more importantly, the drying performance of epoxy linseed oil is stronger than that of methyl esterified soybean oil, which can effectively make up for the problem of insufficient drying caused by replacing the drier.

[0024] (6) 5 - 10 parts of mineral oil, which is used as a diluent and regulator to improve the fluidity of the ink.

[0025] (7) 0.2 - 5 parts each of zinc octoate, iron octoate, and cerium octoate are used as driers simultaneously. Among them, cerium octoate has the functions of surface drying and internal drying, while zinc octoate and iron octoate mainly promote internal drying. At the same time, in the present invention, zinc octoate, iron octoate, and cerium octoate are used to replace the traditional manganese octoate and cobalt octoate driers. Since the redox properties of zinc octoate, iron octoate, and cerium octoate are weaker than those of manganese octoate and cobalt octoate, the phenomenon of peroxidation during drying can be avoided, and the generation of odorous substances such as aldehydes and ketones can be significantly reduced. Through the combined action of these three driers, both the drying of the ink can be ensured and the generation of odors can be prevented.

[0026] (8) 0 - 5 parts of other additives, such as anti-settling agents, dispersants, etc., are used to improve the stability and dispersibility of the ink.

[0027] In addition, in order to enhance the reader experience, a certain amount of plant extract essential oil with a natural aroma is added to the raw materials of the quick-drying and low-odor offset printing ink of the present invention, endowing the ink with a special natural fragrance property, and the smell emitted by the book can make the reader feel as if they are in nature.

[0028] The preparation method of the quick-drying and low-odor offset printing ink of the present invention includes the following steps: A1. Wet the various color pigments and extender pigments with deionized water; A2. Use a specific modified resin and a quick-drying alkyd resin to displace the water at a certain temperature; A3. Stir under negative pressure at 150 °C for 6 hours to obtain a semi-finished product for producing the ink; A4. Grind the semi-finished product until the fineness reaches the specified specification; A5. Add zinc octoate, iron octoate, cerium octoate, and other additives, and use mineral oil to adjust the product specifications to the specified range to obtain the finished ink.

[0029] The preparation method of the specific modified resin of the present invention includes the following steps: B1. Dissolve the specified phenolic modified resin and polyurethane resin with a certain weight part of mineral oil and vegetable oil at 180 °C; B2. Add methyl esterified soybean oil to adjust the viscosity of the diluted resin to the specified range; B3. Cool down to 110 °C and add aluminum diisopropoxyacetoacetate; B4. Under the condition of constant temperature at 110 °C, continue the reaction until the viscosity reaches the specified viscosity.

[0030] The preparation method of the quick-drying alkyd resin of the present invention includes the following steps: C1. Mix a certain weight portion of linseed oil, glycerol, diethylene glycol, and lithium hydroxide, and under an oxygen-free environment, heat the mixture to 240 °C and keep it at a constant temperature for 2 hours; C2. Cool down to 160 °C, and add phthalic anhydride, maleic anhydride, and hydroquinone; C3. Heat up to 230 °C and keep it at a constant temperature for 2 hours; C4. Heat up to 240 °C and keep it at a constant temperature until the viscosity reaches the specified range. Example

[0031] (I) Example 1: This example prepares a specific modified resin, which includes the following steps: Under the condition of 180 °C, dissolve a certain weight portion of mineral oil and vegetable oil in the specified phenolic modified resin and polyurethane resin; Add methylated soybean oil to adjust the viscosity of the diluted resin to the specified range; Cool down to 110 °C, and add aluminum diisopropoxyacetoacetate; Under the condition of a constant temperature of 110 °C, continue the reaction until the viscosity reaches the specified viscosity.

[0032] (II) Example 2: This example prepares a quick-drying alkyd resin, which includes the following steps: Mix a certain weight portion of linseed oil, glycerol, diethylene glycol, and lithium hydroxide, and under an oxygen-free environment, heat the mixture to 240 °C and keep it at a constant temperature for 2 hours; Cool down to 160 °C, and add phthalic anhydride, maleic anhydride, and hydroquinone; Heat up to 230 °C and keep it at a constant temperature for 2 hours; Heat up to 240 °C and keep it at a constant temperature until the viscosity reaches the specified range.

[0033] (III) Example 3: This example 3.1 to 3.4 prepares a quick-drying and low-odor offset printing ink. The raw materials and the amounts of each raw material for each example are shown in Table 1. The preparation method includes the following steps: Moisten various color pigments and extender pigments with deionized water; Use the specific modified resin prepared in Example 1 and the quick-drying alkyd resin prepared in Example 2 to displace the water at a certain temperature; Stir under negative pressure at 150 °C for 6 hours to obtain a semi-finished product for producing ink; Grind the semi-finished product until the fineness reaches the specified specification; Add zinc isooctanoate, iron isooctanoate, cerium isooctanoate, and other additives, and use mineral oil to adjust the product specifications to the specified range to obtain the finished ink.

[0034] Table 1: Raw materials and the dosage of each raw material in Examples 3.1 to 3.4 Raw material components Example 3.1 Example 3.2 Example 3.3 Example 3.4 Various color pigments 30 22 18 15 Specific modified resin 35 31 28 25 Extender pigment 7 7 7 7 Fast-drying alkyd resin 5 6.5 8 10 Epoxy linseed oil 10 14 17 20 Mineral oil 5 6.5 9 10 Zinc isooctanoate 2 3.2 1.8 1 Cerium isooctanoate 2 1 3.2 1.8 Iron isooctanoate 2 1.8 1 3.2 Other additives 5 5 5 5 (IV) Comparative examples: Comparative example 1: A lithographic ink was prepared in this comparative example. The difference from Example 3 was that manganese isooctanoate and cobalt isooctanoate were used as driers, and the remaining steps were the same as those in Example 3.

[0035] Comparative example 2: A lithographic ink was prepared in this comparative example. The difference from Example 3 was that resin - Arakawa Chemical Synthetic Resin 3876 with a technical route mainly based on surface oxidation and film formation was used to replace the specific modified resin in Example 3, and the remaining steps were the same as those in Example 3.

[0036] Comparative example 3: A lithographic ink was prepared in this comparative example. The difference from Example 3 was that an alkyd resin based on soybean oil was used to replace the fast - drying alkyd resin, and the remaining steps were the same as those in Example 3.

[0037] Comparative example 4: A lithographic ink was prepared in this comparative example. The difference from Example 3 was that methyl - esterified soybean oil and soybean oil were used to replace epoxy linseed oil, and the remaining steps were the same as those in Example 3.

[0038] (V) Performance testing: Testing method: According to the preparation methods of the lithographic inks in Examples 3.1 to 3.4 and Comparative examples 1 to 4, a variety of lithographic inks were prepared, and then they were tested according to the following testing methods. The test results are shown in Table 2.

[0039] Odor value: Seal a paper of the same area size and put it into an oven at 80 °C. After heating for 30 min each time, use a highly sensitive indium oxide - based hot - wire - type sintered semiconductor instrument produced in Japan to test the odor of the sample, and record the sum of the values after heating for 120 min (a total of 4 times). Judgment: The larger the evaluation result value, the greater the odor.

[0040] VOCs(%) : According to the test standard in GB 38507 - 2020 "Limits of volatile organic compounds (VOCs) content in inks", the VOC content of the lithographic ink was determined.

[0041] Initial drying performance: Use 0.1 cc of ink to make four-segment proofs on an RI proofing machine. Then, immediately cover it with a blank Jindong coated paper on the 128 g Jindong coated paper, put it into a Japanese-made solidifying tester, and conduct an embossing test under a specific weight. The embossing is intermittent, and the intermittent time can be adjusted. When the color of the test ink is still shown on the blank paper covered on it, it is judged that the surface drying is not complete; otherwise, it can be judged that the surface drying is completed. Judgment: The shorter the time, the faster the surface drying time.

[0042] Abrasion resistance: It is measured by an arc-shaped abrasion wiping tester, and the score ranges from 1 to 5. The higher the score, the better the abrasion resistance.

[0043] Drying time: Use 0.1 cc of ink to make four-segment proofs on an RI proofing machine. Then, immediately cover it with a blank sulfuric acid paper on the 128 g Jindong coated paper, and put it into a Japanese-made rotary drying tester for testing. (Principle: The Japanese-made rotary drying tester will periodically draw across the sulfuric acid paper. If the printed sample is not dry, there will be obvious scratches with the test color; if the printed sample is completely dry, there will be no colored scratches). Judgment: The shorter the time, the faster the drying time.

[0044] Film-forming time: Use a wet film 50 μm preparation instrument to coat the ink on the glass, and then put it into a constant temperature and humidity box with the temperature set at 35 °C and the humidity at 60%, and observe the film-forming time on their surfaces. Judgment: The longer the film-forming time, the better.

[0045] Test results: Table 2: Test results of the offset inks prepared in Examples 3.1 - 3.4 and Comparative Examples 1 - 4 Testing items Odor value (PPM) VOCs (%) Initial drying performance (min) Wear resistance Drying time (h) Film-forming time (h) Example 3.1 423 0.19 9 4.5 10.7 60 Example 3.2 472 0.26 11 4.0 12.2 83 Example 3.3 512 0.31 10 4.0 11.9 68 Example 3.4 501 0.28 8 4.0 12.6 75 Comparative example 1 1396 0.29 10 3.0 10.9 28 Comparative example 2 531 0.38 24 3.0 14.3 51 Comparative example 3 552 0.65 24 3.0 15.2 56 Comparative example 4 687 2.2 20 3.0 14.6 46 Analysis of test results: By comparing and analyzing the performance test results of Examples 3.1 to 3.4 and Comparative Examples 1 to 4, it can be clearly seen that the offset ink prepared by the method for preparing a quick-drying and low-odor offset ink of the present invention has been significantly improved in terms of odor value, VOCs content, initial drying performance, abrasion resistance, drying time, etc.

[0046] By comparing Example 3 with Comparative Example 1, it can be seen that the present invention uses zinc isooctanoate, iron isooctanoate, and cerium isooctanoate together as driers. Compared with the traditional manganese isooctanoate and cobalt isooctanoate driers, it can not only ensure the drying of the ink but also prevent the generation of odor.

[0047] By comparing Example 3 with Comparative Example 2, it can be seen that the specific modified resin used in the present invention has the ability to quickly complete absorptive drying compared with the resin with a technical route mainly based on surface oxidation film formation, and can effectively improve the initial drying performance and drying performance of the ink.

[0048] Combining Example 3 and Comparative Example 3, it can be seen that the quick-drying alkyd resin used in the present invention has stronger advantages in terms of drying property compared with the alkyd resin based on soybean oil. It realizes the drying mode of replacing oxidative film-forming drying with absorptive drying of the ink, accelerates the drying process of the ink, and improves the drying property and printing efficiency of the ink.

[0049] Combining Example 3 and Comparative Example 4, it can be seen that the epoxy linseed oil used in the present invention is almost odorless compared with methyl esterified soybean oil and soybean oil, and can prevent the generation of odor. At the same time, the initial drying property and drying property of epoxy linseed oil are stronger than those of methyl esterified soybean oil, and can effectively make up for the problem of insufficient drying property caused by replacing the drier.

[0050] Thus, it can be seen that the quick-drying low-odor offset printing ink prepared by the present invention has excellent performance characteristics and printing effects such as low odor and fast drying, while maintaining good fluidity and stability. It is suitable for large-scale industrial production and has high practical value and popularization prospects.

[0051] Regarding the embodiments of the present invention, it should also be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0052] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. The protection scope of the present invention should be subject to the protection scope of the claims. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to obtain equivalent embodiments with equivalent changes, but as long as it does not depart from the technical content of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A quick-drying and low-odor offset printing ink, characterized in that, It includes the following raw materials in parts by weight: 15-30 parts of various pigments, 25-35 parts of a specific modified resin, 3-10 parts of extender pigment, 5-10 parts of fast-drying alkyd resin, 10-20 parts of epoxy linseed oil, 5-10 parts of mineral oil, 0.2-5 parts of zinc isooctanoate, 0.2-5 parts of iron isooctanoate, and 0.2-5 parts of cerium isooctanoate.

2. The quick-drying and low-odor offset printing ink according to claim 1, wherein, The solubility of the specific modified resin is 3-5, and the acid value ≤10.

3. The quick-drying and low-odor offset printing ink according to claim 2, wherein The specific modified resin is made from the following raw materials: phenolic modified resin, polyurethane resin, mineral oil, vegetable oil, methyl esterified soybean oil, and aluminum diisopropoxyacetoacetate.

4. The quick-drying and low-odor offset printing ink according to claim 1, wherein, The molecular formula of the specific modified resin is: (C15H16O2·C3H8O3·CH2O·W99)x.

5. The quick-drying and low-odor offset printing ink according to claim 1, wherein The viscosity of the specific modified resin at 25°C is 5000-6000 mPa·s.

6. The quick-drying and low-odor offset printing ink according to claim 1, wherein The fast-drying alkyd resin is made from the following raw materials: linseed oil, glycerol, diethylene glycol, lithium hydroxide, phthalic anhydride, maleic anhydride, and hydroquinone.

7. The quick-drying and low-odor offset printing ink according to claim 1, characterized in that, The raw materials of the fast-drying and low-odor offset printing ink further include plant-extracted essential oil.

8. A preparation method of a quick-drying and low-odor offset printing ink, characterized in that, It includes the following steps: Wet various pigments and extender pigment with deionized water; Use the specific modified resin and fast-drying alkyd resin to displace the water at a certain temperature; Stir under negative pressure at 150°C for 6 hours to obtain a semi-finished product for producing ink; Grind the semi-finished product until the fineness reaches the specified specification; Add zinc isooctanoate, iron isooctanoate, cerium isooctanoate, and other additives, and use mineral oil to adjust the product specification to the specified range to obtain the finished ink.

9. The method for preparing a quick-drying and low-odor offset printing ink according to claim 8, characterized in that, The preparation method of the specific modified resin includes the following steps: At 180°C, use a certain weight of mineral oil and vegetable oil to dissolve the specified phenolic modified resin and polyurethane resin; Add methyl esterified soybean oil to adjust the viscosity of the diluted resin to the specified range; Cool down to 110°C and add aluminum diisopropoxyacetoacetate; Under the condition of constant temperature at 110°C, continue to react until the viscosity reaches the specified viscosity.

10. The method for preparing a quick-drying and low-odor offset printing ink according to claim 8, wherein The preparation method of the fast-drying alkyd resin includes the following steps: Mix a certain weight of linseed oil, glycerol, diethylene glycol, and lithium hydroxide, and under the environment of oxygen isolation, heat up to 240°C and keep it at a constant temperature for 2 hours; Cool down to 160°C and add phthalic anhydride, maleic anhydride, and hydroquinone; Heat up to 230°C and keep it at a constant temperature for 2 hours; Heat up to 240°C and keep it at a constant temperature until the viscosity reaches the specified range.