CN100500773C - A kind of digital inkjet printing ink and preparation method thereof - Google Patents

Abstract

The present invention uses polycarboxylic acid type high-molecular copolymer as dispersing agent and fixing agent to prepare superfine pigment ink as ink-jet printing ink. It is characterized by that the pigment dispersing agent and fixing agent are made into the same compound, after it is jetted and printed, the high temperature can be used to fix the pigment on the fibre and obtain required fastness. The average grain size of pigment granules prepared by said method is less than 300 nm.

Description

A kind of digital inkjet printing ink and preparation method thereof

technical field

A digital inkjet printing ink and a preparation method thereof relate to the technical fields of polymer chemistry and textile inkjet printing.

technical background

Digital inkjet printing is a new frontier topic for the future development of computer inkjet printing technology. Compared with traditional printing technology, digital inkjet printing technology for textiles has the following main advantages: (1) High printing fineness, resolution can reach 1440dpi, get photo effects, while the traditional screen printing can only reach 200dpi. The substantial increase in printing fineness provides designers with a wealth of imagination space, making it possible to produce high-definition printed textiles. (2) There is no need for plate making, and the batch size is flexible. It can realize single-piece production or mass production, and the delivery speed is fast. Traditional printing requires plate making, color matching, and proofing in advance. The more colors of the pattern, the more editions are required, and the longer the preparation time. When the production batch is small, the production cost is higher and the delivery speed is slower. Therefore, traditional printing methods cannot produce single pieces or small batches according to customer requirements, and cannot meet the individual needs of modern consumers. (3) Personalized e-commerce consumption can be realized through the Internet. Consumers can transmit the patterns, personal data and requirements they need to the manufacturer through the Internet, and the manufacturer can immediately arrange production and send the product to the consumer. (4) No waste and waste of dyes and additives, no sewage discharge. Traditional printing needs to wash the pattern, and the printed fabric needs to be washed and soaped to remove floating colors, which not only causes waste of dyes, auxiliaries, water resources and energy, but also causes serious pollution. (5) It occupies a small area and can be printed in offices and homes. Traditional printing requires a special drawing room, a plate making room, a large printing workshop and a post-washing treatment workshop, and the cost of the production plant is high and the investment is large. These unique advantages of textile digital inkjet printing have fundamentally innovated people's concept of traditional textile production and management, solved the problem of environmental pollution in textile production, and organically combined traditional textile industry with modern high-tech, making it from The development from labor-intensive to technology-intensive has greatly promoted the upgrading and technological level of the textile industry. Textile digital inkjet printing technology will be the key technology for the revolution of the textile industry in the 21st century. The research and development of printing ink is one of the key issues that need to be solved in the popularization and application of this technology.

In terms of inkjet printing inks for textiles, dye inks are still the main ones. Due to the increasingly prominent shortcomings of dye inks in digital inkjet printing of textiles, such as (1) inks are not universal, different fibers need to use different inks, and ink replacement requires cleaning nozzles and pipelines. (2) The production process is complicated, and it is necessary to pre-treat the fabric to apply dye fixing agents and catalysts on the fabric. After printing, the fabric needs to be steamed, washed and other post-treatments to fix the dye on the fiber and remove unfixed dyes, etc., there is a certain degree of environmental pollution. These shortcomings of dye inks have seriously hindered the popularization and application of textile digital inkjet printing technology, so IBM, Xerox (XEROX), Hewlett-Packard (HEWLETT-PACKARD), Kodak (EASTMAN KODAK), DuPont (DUPONT) in the United States, Bayer ( BAYER), BASF (BASF), Japan's Epson (EPSON), Konica (KONIKA), Switzerland's Ciba (CIBA), South Korea's Samsung (SAMSUNG) and other multinational companies have invested heavily in digital inkjet printing pigments. Ink research and development.

In addition to these multinational companies, the governments of developed countries such as the United States and Japan also attach great importance to the research and development of digital inkjet printing universal inks. Ink research, through the modification of the existing reactive dyes, the dye ink that can be polymerized has been prepared, thus overcoming some shortcomings of ordinary dye inks. However, the technology used in inkjet printing also has shortcomings such as insufficient color depth and poor ink stability. Although there are researches and reports on dye inks in China, there is still a big gap between the product level and foreign products, and there are still many problems to be solved in practical application. In terms of research and development of general-purpose pigment inks, there are domestic explorations on polyacrylic binders for pigment inks.

Ink with pigment instead of dye has become the trend of ink development. The key to the manufacture of pigment inks is the ultra-fine processing technology of pigments and the color fixing technology of pigments on fibers, because the diameter of the nozzle is small, and the large pigment particles are easy to block the nozzle. Moreover, the stability of the pigment dispersion system with coarse particle size is relatively poor, and it is easy to stratify or precipitate during storage and use, which affects the service life of the equipment. On the other hand, when the particle size of the pigment is below 500 nanometers, it has the highest tinting strength, vividness and transparency. Different from inkjet printing on paper, the pigment printed on the fiber must have sufficient color fastness to washing and rubbing, so how to permanently fix the pigment on the fiber is an important issue that must be considered. The color fixing technology of digital inkjet printing pigments cannot adopt the general pigment printing method, because there are many essential differences between inkjet printing ink and pigment printing paste.

Contents of the invention

The object of the present invention is to provide a kind of digital ink-jet printing ink and preparation method thereof, the ink-jet printing ink prepared by the method of the present invention has good dispersion stability and storage stability, and can obtain realistic image effect when used in fabric printing and excellent color fastness.

Technical solution of the present invention: the digital inkjet printing ink provided by the present invention is stirred and mixed by pigment, polycarboxylic acid polymer dispersant, water-soluble co-solvent, nonionic surfactant and deionized water, emulsified and crushed at high speed The water-based pigment ink-jet printing ink is prepared, the prepared ink has a viscosity of 2-8cP, a surface tension of 25-35mN/m, a Z-average particle diameter of pigment particles of 35-300nm, a Zeta potential of -20--40mV, and a pH value of 6-9.

The preparation method of the digital inkjet printing ink is as follows: 1-15% pigment, 1-10% polycarboxylic acid copolymer, 10-50% water-soluble co-solvent, 0.1-3% non-ionic surfactant, 25- 75% deionized water, add alkali to the polycarboxylic acid copolymer according to the formula, the amount of alkali is 10-20% of the mass of the copolymer, add deionized water, heat to completely dissolve the polymer, and hydrolyze it into water-soluble polycarboxylic acid Type polymer dispersant, then add pigment, water-soluble co-solvent and non-ionic surfactant, after mixing, stir with a mixer at 500-1000 rpm for 20-50 minutes, then use an emulsifier at 8000-30000 rpm for 30- After 80 minutes, crush it with a sand mill for 20-300 minutes, finally adjust the pH value to 6-9, and filter it with a 0.5-1 μm microporous membrane to obtain the water-based pigment ink.

Types of pigments used in the ink:

Black pigments include C.I. Pigment Black 7, C.I. Pigment Black 11; yellow pigments include C.I. Pigment Yellow 3, C.I. Pigment Yellow 12, C.I. Pigment Yellow 17, C.I. Pigment Yellow 23, C.I. Pigment Yellow 34, C.I. Pigment Yellow 42, C.I. Yellow 55, C.I. Pigment Yellow 95, C.I. Pigment Yellow 100, C.I. Pigment Yellow 104, C.I. Pigment Yellow 108, C.I. Pigment Yellow 120, C.I. Pigment Yellow 153; red pigments include C.I. Pigment Red 1, C.I. Pigment Red 2, C.I. Pigment Red 5. C.I. Pigment Red 7, C.I. Pigment Red 23, C.I. Pigment Red 38, C.I. Pigment Red 48:2, C.I. Pigment Red 48:4, C.I. Pigment Red 49:1, C.I. Pigment Red 52:2, C.I. Pigment Red 57: 1. C.I. Pigment Red 63:1, C.I. Pigment Red 64:1, C.I. Pigment Red 81, C.I. Pigment Red 88, C.I. Pigment Red 92, C.I. Pigment Red 101, C.I. Pigment Red 104, C.I. Pigment Red 105, C.I. Pigment Red 106 , C.I. Pigment Red 108, C.I. Pigment Red 112, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 146, C.I. Pigment Red 149, C.I. Pigment Red 166, C.I. Pigment Red 168, C.I. , C.I. Pigment Red 185, C.I. Pigment Red 190, C.I. Pigment Red 209, C.I. Pigment Red 219; blue pigment varieties include C.I. Pigment Blue 1, C.I. Pigment Blue 15, C.I. Pigment Blue 15:1, C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, C.I. Pigment Blue 15:6, C.I. Pigment Blue 16, C.I. Pigment Blue 17:1, C.I. Pigment Blue 56, C.I. Pigment Blue 63.

1. Polycarboxylate polymer dispersant for pigment modification:

The polymer dispersant prepared by the present invention is a copolymer of ethylene monomers, and the copolymer forming the dispersant has the following chemical structural formula:

In the above formula, M ₁ =H ⁺ , Na ⁺ , NH ₄ ⁺ , K ⁺ , M ₂ =H ⁺ , Na ⁺ , NH ₄ ⁺ , K ⁺ , CH ₃ , CH ₂ CH ₃ , R ₁ =H, CH ₃ , R=COOH, CN, CONH ₂ , COOCH ₃ , COOCH ₂ CH ₃ , COOC ₄ H ₉ , C ₆ H ₅ , R ₂ =COOH, CN, CONH ₂ , COOCH ₃ , COOCH ₂ CH ₃ , COOC ₄ H ₉ , C ₆ H ₅ .

The number-average molecular weight of the dispersant is 1000-50000, the dosage of the dispersant in the ink is 1-10%, and the applicable pH range is 6-9.

2. Non-ionic surfactants in ink:

The above-mentioned polymer dispersant is used in conjunction with a nonionic surfactant, and the nonionic surfactant used in the ink is polyoxyethylene alkylphenol condensate: OP-7, OP-10 or OP-15; polyoxyethylene fatty alcohol Condensate: Pingpinga O-10, Pingpinga O-20, Pingpinga O-25 or Pingpinga A-20; polyoxyethylene polyol ether fatty acid ester: such as Tween40, Tween60, Tween65 or Tween80; polyoxygen of fatty acid Vinyl esters: such as SG-10, SE-10, OE-15; these surfactants can be used alone or in combination.

3. Water-soluble co-solvent in ink:

Ethanol, n-propanol, isopropanol, n-butanol, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, diethylene glycol Ethylene glycol, tetraethylene glycol, polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, glycerol, triethanolamine, pentaerythritol, 2-pyrrolidone, N-methyl-2-pyrrolidone Three to eight of them.

Beneficial effects of the present invention: the present invention uses polycarboxylic acid polymer copolymers as dispersants and fixatives to prepare ultra-fine pigment inks, makes pigment dispersants and color fixatives into the same component, and after inkjet printing, undergoes high-temperature use. The pigment is fixed on the fiber to obtain the required fastness, which shortens the inkjet printing process. The average particle size of the pigment particles prepared by this method is less than 300nm. Since the ultrafine pigment particle size is only one percent of the nozzle aperture, the pigment particle size is small and easy to pass through the nozzle. The polycarboxylate polymer dispersant makes the ultrafine pigment ink have good dispersion stability and storage stability by virtue of the combined effect of steric hindrance and electric double layer. Polycarboxylate is a liquid that is difficult to dry and crystallization is difficult to form due to the polydispersity of molecular weight. Therefore, when used in inkjet printing ink, even if the water at the nozzle volatilizes, it is difficult to precipitate or form a film, and it has good compatibility with other components in the ink system. Polycarboxylic acid is very soluble in water. The carboxyl group in the water is ionized and is in a dissolved state. The carboxyl group in the polycarboxylic acid molecule can form hydrogen bonds and van der Waals forces with polar groups such as hydroxyl, carbonyl, and amino groups in pigment molecules. Due to the partial ionization of the carboxyl group, these pigment particles are partially negatively charged, which causes electrostatic repulsion between the pigment particles, thus avoiding the collision between the pigment particles due to Brownian motion, which occurs Aggregation, making the particle diameter larger, or causing precipitation. Therefore, polycarboxylic acid can increase the dispersion stability of the pigment in the ink.

Polyhydric alcohols in ink can adjust ink viscosity, reduce ink surface tension, increase the dispersion stability of pigment particles, etc. In addition, the ink system composed of polycarboxylic acid and polyhydric alcohol has a relatively strong intermolecular interaction with cellulose fibers force. On the other hand, the carboxyl group in the polycarboxylic acid can also undergo esterification and crosslinking with the polyol hydroxyl group under high temperature conditions, and fix the pigment particles sprayed on the substrate on the substrate, so that it has the required color fastness.

Advantages of the present invention are summarized as follows:

(1) The particle size of the pigment particles modified by the polymer dispersant in the ink is less than 300nm, and it is not easy to produce large particles of insoluble matter during storage, ensuring the long-term stability of the ink system.

(2) Due to the addition of co-solvent, the surface tension, viscosity, moisturizing performance and foaming performance of the ink are adjusted. According to different printing equipment, ink mixtures with different surface tension and viscosity are prepared, which have excellent printing performance and are not Blocking the nozzle, good printability, and can effectively control the line width of the printed pattern, reduce the feathering phenomenon, and improve the printing quality. Suitable for Mimaki inkjet printers, Mutoh inkjet printers and other printing equipment suitable for water-based inks.

(3) Due to the addition of polyols in the co-solvent, the carboxyl groups in the polycarboxylic acid polymer dispersant can undergo esterification and crosslinking with the hydroxyl groups of polyols under high temperature conditions, and the pigment particles sprayed on the fabric are fixed on the fabric On, so that it has the required color fastness.

Detailed ways

The preparation of embodiment 1 red ink

Get 4g maleic anhydride-methyl acrylate-butyl methacrylate copolymer ( $\stackrel{\‾}{m_{\mathrm{no}}}=10000\±100,$ Molar ratio maleic anhydride: methyl acrylate: butyl methacrylate=1:0.5:1), add 0.4g sodium hydroxide, 51g deionized water, heat and make polymer dissolve completely, then add the CI pigment red of 5g successively 112, 1g of OP-15 emulsifier, 3g of ethanol, 15g of diethylene glycol, 10g of ethylene glycol, 10g of glycerol, and 1g of n-butanol were stirred with a mixer at 600 rpm for 25 minutes, emulsified Stir at a high speed of 10,000 rpm for 50 minutes, pulverize with a sand mill for 30 minutes, adjust the pH value to 8, and filter with a 0.5-1 μm microporous membrane to obtain a water-based pigment magenta ink. The physical properties of this ink at 20°C are as follows: surface tension σ=28.7mN/m, viscosity η=5.5cP, particle Z average particle size d=120nm, Zeta potential ξ=-37.5mV.

The preparation of embodiment 2 yellow ink

Get 3g methyl methacrylate-maleic anhydride-acrylonitrile-butyl acrylate copolymer ( $\stackrel{\‾}{m_{\mathrm{no}}}=30000\±200,$ Molar ratio methyl methacrylate: maleic anhydride: acrylonitrile: butyl acrylate = 1:1.5:0.3:1), add 0.5g potassium hydroxide, 54g deionized water, heat to dissolve the polymer completely, and then add 6g of CI Pigment Yellow 17, 1.5g of Tween 80, 5g of N-methyl-2-pyrrolidone, 5g of 1,3-propylene glycol, 10g of polyethylene glycol 200, 10g of triethylene glycol, 5g of iso Propanol was stirred with a mixer at 500 rpm for 50 minutes, an emulsifier at 15,000 rpm at a high speed for 70 minutes, and a sand mill for 120 minutes. Finally, adjust the pH value to 7 and filter with a 0.5-1 μm microporous membrane. That is, the water-based pigment yellow ink is obtained. The physical properties of this ink at 20°C are as follows: surface tension σ=32.2mN/m, viscosity η=6.5cP, particle Z average particle size d=137nm, Zeta potential ξ=-34.2mV.

The preparation of embodiment 3 blue ink

Get 5g styrene-maleic anhydride-acrylamide-butyl methacrylate copolymer ( $\stackrel{\‾}{m_{\mathrm{no}}}=25000\±200,$ Molar ratio styrene: maleic anhydride: acrylamide: butyl methacrylate=1:2:0.5:1), add 20% ammoniacal liquor 5g, deionized water 58g, heat it to dissolve completely, then add 4g of CI Pigment blue 56, 2g Pingpingjia O-25, 3g isopropanol, 3g triethanolamine, 5g 1,6-hexanediol, 10g diethylene glycol, 5g polyethylene glycol 400, 5g 2- Pyrrolidone was stirred with a mixer at 800 rpm for 40 minutes, an emulsifier at 20,000 rpm at a high speed for 30 minutes, and pulverized with a sand mill for 80 minutes. Finally, adjust the pH value to 6 and filter with a microporous membrane of 0.5 to 1 μm. Get water-based pigment blue ink. The physical properties of this ink at 20°C are as follows: surface tension σ=29.8mN/m, viscosity η=4.85cP, particle Z average particle size d=102nm, zeta potential ξ=-31.9mV.

The preparation of embodiment 4 black ink

Get 7g styrene-maleic anhydride-ethyl methacrylate-butyl acrylate copolymer ( $\stackrel{\‾}{m_{\mathrm{no}}}=32000\±200,$ Molar ratio styrene: maleic anhydride: ethyl methacrylate: butyl acrylate=1:3:0.8:1), add 1g of sodium hydroxide, 51g of deionized water, heat it to dissolve completely, then add 10g of CI pigment black 7, 1g SE-10, 4g of ethylene glycol, 3g of n-butanol, 15g of diethylene glycol, 5g of triethylene glycol, 4g of pentaerythritol were stirred with a mixer at 600 rpm for 20 Minutes, emulsifier 10000 rpm high-speed stirring for 40 minutes, sand mill pulverization for 100 minutes, finally adjust the pH value to 7, and filter with a 0.5-1 μm microporous membrane to obtain a water-based pigment black ink. The physical properties of this ink at 20°C are as follows: surface tension σ=30.2mN/m, viscosity η=4.15cP, particle Z average particle size d=172nm, zeta potential ξ=-37.2mV.

Claims (4)

1. the preparation method of a tax stamp ink digital ink jet, it is characterized in that prescription is: 1%-15% pigment, 1%-10% polyocarboxy acid type macromolecule dispersing agent, 10%-50% water-soluble cosolvent, 0.1%-3% nonionogenic tenside, 25%-75% deionized water, by prescription carboxylic acid-based copolymer is added alkali, add deionized water, heating is dissolved polymkeric substance fully, is hydrolyzed into water miscible polyocarboxy acid type macromolecule dispersing agent, adds pigment then, water-soluble cosolvent and nonionogenic tenside, stirred 20-50 minutes for 500-1000 rev/mins with stirrer mixed back, use mulser to stir 30-80 minutes for 8000-30000 rev/mins then, pulverized 20-300 minute with sand mill again, regulate the pH value at last after 6-9, with the filtering with microporous membrane of 0.5～1 μ m, promptly obtain aqueous pigment ink;

The general structure of used polyocarboxy acid type macromolecule dispersing agent is

M in the following formula ₁=H ⁺, Na ⁺, NH ₄ ⁺, K ⁺, M ₂=H ⁺, Na ⁺, NH ₄ ⁺, K ⁺, CH ₃, CH ₂CH ₃, R ₁=H, CH ₃, R=COOH, CN, CONH ₂, COOCH. //. ₃, COOCH ₂CH ₃, COOC ₄H ₉, C ₆H ₅, R ₂=COOH, CN, CONH ₂, COOCH ₃, COOCH ₂CH ₃, COOC ₄H ₉, C ₆H ₅This dispersion agent number-average molecular weight is 1000-50000, and the consumption in ink is 1-10%, and the pH scope that is suitable for is 6-9.

2. preparation method according to claim 1 is characterized in that used pigment comprises C.I. Pigment black 7, C.I. Pigment black 11 for the black pigment kind; The yellow ultramarine kind comprises C.I. Pigment Yellow 73 3, C.I. pigment Yellow 12, C.I. pigment yellow 17, C.I. Pigment Yellow 73 23, C.I. pigment yellow 34, C.I. Pigment Yellow 73 42, C.I. Pigment Yellow 73 55, C.I. Pigment Yellow 73 95, C.I. Pigment Yellow 73 100, C.I. Pigment Yellow 73 104, C.I. Pigment Yellow 73 108, C.I. pigment Yellow 12 0, C.I. Pigment Yellow 73 153; The red pigment kind comprises C.I. Pigment red 1, C.I. Pigment red 2, C.I. Pigment red 5, C.I. Pigment red 7, C.I. Pigment red 23, C.I. pigment red 38, C.I. pigment red 4 8:2, C.I. pigment red 4 8:4, C.I. pigment red 4 9:1, C.I. Pigment red 52:2, C.I. Pigment red 57:1, C.I. Pigment red 63:1, C.I. Pigment red 64:1, C.I. pigment red 81, C.I. pigment Red 88, C.I. Pigment Red 92, C.I. Pigment red 101, C.I. Pigment red 104, C.I. Pigment red 105, C.I. Pigment red 106, C.I. Pigment red 108, C.I. Pigment Red 112, C.I. pigment red 122, C.I. pigment red 123, C.I. pigment red 146, C.I. pigment red 149, C.I. Pigment red 166, C.I. Pigment red 168, C.I. Pigment red 170, C.I. Pigment red 172, C.I. Pigment red 185, C.I. Pigment red 190, C.I. Pigment red 209, C.I. pigment red 21 9; The blue pigments kind comprises C.I. pigment blue 1, C.I. pigment Blue 15, C.I. pigment Blue 15: 1, C.I. pigment Blue 15: 3, C.I. pigment Blue 15: 4, C.I. pigment Blue 15: 6, C.I. pigment blue 16, C.I. pigment blue 1 7:1, C.I. Pigment blue 56, C.I. Pigment blue 63.

3. preparation method according to claim 1, it is characterized in that used water-soluble cosolvent comprises ethanol, n-propyl alcohol, Virahol, propyl carbinol, ethylene glycol, 1,3-propylene glycol, 1, in 4-butyleneglycol, 1,6-hexylene glycol, glycol ether, Triethylene glycol, tetraethylene-glycol, Macrogol 200, poly(oxyethylene glycol) 400, Polyethylene Glycol-600, glycerol, trolamine, tetramethylolmethane, 2-pyrrolidone, the N-methyl-2-Pyrrolidone three to eight kinds.

4. preparation method according to claim 1 is characterized in that used ionic surfactant pack draws together polyoxyethylene alkylphenol condenses: OP-7, OP-10 or OP-15; Polyoxyethylene Fatty Alcohol(C12-C14 and C12-C18) condenses: paregal O-10, paregal O-20, paregal O-25 or peregal A-20; Polyoxyethylene polyols ether fatty acid ester: Tween 40, Tween 60, Tween 65 or Tween 80; The polyoxyethylene ester of lipid acid: SG-10, SE-10 or OE-15; Used tensio-active agent is one or more in the above-mentioned tensio-active agent.