CN106189514B - Water-based dispersant of black blue and white colorant for inkjet printing and its preparation method and application - Google Patents

Abstract

The invention specifically relates to a water-based dispersant of black blue and white color material for inkjet printing, a preparation method and an application method thereof. The dispersant contains a flexible polysiloxane main chain, which contains dopamine units and primary amino groups, and also has polyether side chains containing carboxyl groups. The dopamine unit and the primary amino group can firmly cooperate with the surface of manganese, iron, and chromium oxide pigment particles; the polysiloxane main chain can ensure that the dispersant molecules are attached to the surface of the pigment particles as much as possible, and It can reduce the surface tension of ceramic ink; the polyether side chain containing carboxyl group can be dispersed in water, and at the same time, under slightly alkaline conditions, the carboxyl group is ionized to generate a negative charge layer on the surface of the colorant particles, further inhibiting the agglomeration and sedimentation of the colorant particles .

Description

Water-based dispersant of black blue and white colorant for inkjet printing and its preparation method and application

technical field

The invention belongs to the technical field of organic/inorganic composite functional materials, and in particular relates to a water-based dispersant of black blue and white color material for inkjet printing, a preparation method thereof and its application in the field of inkjet printing.

Background technique

Ceramic digital inkjet printing technology is a new type of ceramic printing technology developed in the past five years. It has the advantages of realistic and delicate printing effect, low printing cost and damage rate, and can realize the personalized design and manufacture of ceramic products. The preparation of ceramic ink is a key link in inkjet printing technology. Colorants and dispersants are two important components of ceramic inks, and their quality greatly determines the quality of ceramic inks.

Dispersant is a kind of polymer with amphiphilicity, which can effectively reduce the interfacial energy between the pigment particles and the solvent. The molecular structure of the dispersant is usually composed of two or more components, namely the anchor group Divide and disperse components. Compared with the dispersing component, the anchoring component usually has a stronger polarity, and can coordinate or attract metal oxide ions on the surface of the colorant particles, so that the dispersant molecules are adsorbed on the surface of the colorant particles. The dispersing components are usually of weak polarity, and they themselves can be well dissolved in solvents.

Dispersants can be divided into oil-based dispersants and water-based dispersants according to their solubility, and ceramic inks prepared from them can also be divided into oil-based inks and water-based inks. As a solvent for ceramic ink, water has the unique advantage of being environmentally friendly. At the same time, during the production process, the production equipment of water-based ink is also easy to clean and wash. However, compared with oil solvents, water has a higher surface tension, which is not conducive to fine inkjet printing.

On the other hand, for different types of colorants, the molecular structure of the dispersant is also different. The black blue color pigment in the ceramic ink is mainly composed of manganese oxides, iron oxides and chromium oxides. Compared with pigments of other colors, the performance of the dispersant matching the black blue and white color pigments currently on the market still needs to be improved, and the solid content of the ink still needs to be strengthened. The main reasons are: 1) the anchoring effect of the anchoring component of the dispersant on manganese, iron, and chromium oxides is not ideal; 2) the anti-agglomeration effect of the dispersing component in the dispersant still needs to be improved.

Contents of the invention

The object of the present invention is to provide a kind of novel graft copolymer as dispersing agent, this dispersing agent can effectively improve the dispersing effect to black blue and white pigment particle in water solvent, and the surface tension of this black blue and white ink also obtains certain decrease.

Another object of the present invention is to provide the preparation method of the above-mentioned black blue and white pigment water-based dispersant;

Another object of the present invention is to provide an application method of the above-mentioned aqueous dispersant of black blue and white colorant in the field of inkjet printing.

A kind of black blue and white pigment aqueous dispersant for inkjet printing, structure has the structural characteristics of the graft copolymer as shown below:

PHMS-g-(DOPA-r-EDA-r-PEGDMA)

Among them, g stands for grafting, r stands for random distribution; PHMS stands for hydrogen-containing polysiloxane polymer chain; DOPA stands for dopamine unit; EDA stands for ethylenediamine; .

Further, the mass molar ratio of DOPA and EDA is 1.0:1.0˜1.0:5.0, and the mass molar ratio of DOPA and PEGDMA is 1.0:0.1˜1.0:2.0.

A kind of black blue and white pigment aqueous dispersant for inkjet printing is prepared by the following method:

(1) Dissolve PHMS and glycidyl methacrylate (GMA) in solvent A, wherein the mass ratio of PHMS and GMA is 1:1 to 1:15, and then add platinum catalyst, wherein the relative ratio of catalyst and epoxy unit The mass fraction is 0.01% to 0.1%, and then use inert gas to deoxygenate by bubbling for 10 to 60 minutes, heat and reflux at 40 to 100°C for 2 to 12 hours, after the reaction is completed, pour 0.5 to 5 times the volume of solvent B to wash , and then stand still to separate the liquid for 5-30 minutes, collect the lower layer liquid, and dry it in vacuum at room temperature to obtain epoxy-functionalized PHMS;

(2) Take a certain amount of epoxy-functionalized PHMS, dissolve it in solvent C, and the mass concentration after dissolving is 10% to 40%, and add dicarboxypolyethylene dicarboxylate 1 to 10 times the mass of epoxy-functionalized PHMS Alcohol, then add dopamine hydrochloride 0.05 to 0.5 times the mass of the epoxy-functionalized PHMS, and finally add 0.1% to 2.0% NaOH solution relative to the mass of the epoxy-functionalized PHMS, heat and reflux at 40 to 80°C for 0.5 ～6 hours, then add ethylenediamine 0.01～0.2 times the mass of epoxy-functionalized PHMS, and continue to heat and reflux at 40～80°C for 0.5～6 hours. After the reaction is completed, the entire solution is concentrated to the original 1/10 to 1/2 of the volume to obtain a water-based dispersant of black blue and white color material for inkjet printing.

Wherein, the molecular weight of the PHMS described in the step (1) is 500～10000Da, and the hydrogen substitution degree is 40%～80%; The described solvent A is a kind of in xylene, toluene, benzene; The described solvent B It is one of methanol, ethanol, isopropanol and n-hexane;

Solvent C described in step (2) is a kind of in dimethylformamide, dimethylacetamide, benzene, toluene, xylene, methylene chloride, chloroform; The molecular weight of alcohol is 2000-20000Da.

A kind of water-based dispersant of black blue and white color material for inkjet printing can be applied to the preparation of black blue and white ink, and the black and blue and white ink is realized by the following technical means:

a. Add the dispersant to the black blue color pigment, wherein the mass fraction of the dispersant in the pigment is 10% to 20%, add distilled water, wherein the total mass of the pigment and the dispersant accounts for 30% in the system % to 50%, set the speed of the stirrer at 60 to 240 rpm, and perform a pre-stirring operation for 15 to 120 minutes.

b. Add the pre-stirred mixture into the ball mill, set the rotation speed to 6000-12000 rpm, and ball mill for 30-150 minutes. During the ball milling process, use dilute lye to continuously and slowly adjust the pH value of the mixture to 7.0-9.0. Get a black cyan ink for inkjet printing.

Principle of the present invention is:

A water-based dispersant of black cyan colorant for inkjet printing, the synthesis method of which is based on hydrosilylation reaction and epoxy ring-opening reaction. During the ball milling process, the dopamine anchoring group and the primary amino group contained in the main chain of the dispersant are combined with the soft siloxane main chain to produce stable multi-point synergistic adsorption on the surface of the black blue color pigment particles, and the dispersant Firmly fixed on the surface of black cyan color pigment particles. The carboxyl group contained in the dispersed chain of the dispersant is in a negative ion state under slightly alkaline conditions, which can form an electrostatic layer on the surface of the colorant particles, enhance the repulsion effect between the colorant particles, and prevent the agglomeration and sedimentation of the colorant. On the other hand, the introduction of siloxane main chain can also reduce the surface tension of ceramic ink products to a certain extent.

Compared with the prior art, the present invention has the following advantages and effects:

(1) The main chain of the dispersant is polysiloxane, which has excellent flexibility, so that the dispersant molecules can fully contact the surface of the colorant particles, enhance the adsorption probability, and reduce the surface tension of the ceramic ink;

(2) The dopamine and primary amine groups in the dispersant have an excellent anchoring effect on manganese, iron, and chromium oxide particles, making the adsorption of the dispersant stable for a long time;

(3) The main chain of the dispersant contains multiple dopamine and primary amine units, which can effectively realize the synergistic adsorption on the surface of the colorant particles and enhance the adsorption effect of the dispersant;

(4) The end of the dispersion chain of the dispersant contains carboxyl functional groups, which are ionized under slightly alkaline conditions, can form a negative charge layer, and effectively prevent the collision and agglomeration of colorant particles.

Description of drawings

Fig. 1 is a kind of synthesizing route synoptic diagram of the black blue and white pigment aqueous dispersant that is used for ink-jet printing;

Fig. 2 is a ¹ H NMR spectrogram of an aqueous dispersant of black cyan colorant prepared in Example 4 for inkjet printing.

Detailed ways

The present invention will be further described in detail below in conjunction with the embodiments and the accompanying drawings, but the embodiments of the present invention are not limited thereto.

The raw material used in the embodiment is as follows:

Example 1

A kind of black blue and white pigment aqueous dispersant for inkjet printing is prepared by the following method:

(1) Get PHMS (molecular weight is 500Da, degree of hydrogen substitution 40%) and GMA are dissolved in xylene, wherein the mass ratio of PHMS and GMA is 1:15, then add platinum catalyst, wherein the relative mass of catalyst and epoxy unit The fraction is 0.01%, then use inert gas bubbling to deoxygenate for 10 minutes, heat and reflux at 40°C for 12 hours, after the reaction is completed, pour 0.5 times the volume of methanol to wash, and then let stand to separate the liquid for 30 minutes, collect the lower layer liquid, Vacuum drying at room temperature to obtain epoxy-functionalized PHMS.

(2) Take a certain amount of epoxy-functionalized PHMS, dissolve it in dimethylformamide, the mass concentration after dissolving is 10%, add dicarboxypolyethylene glycol 1 times the quality of epoxy-functionalized PHMS, Add 0.05 times the mass of epoxy-functionalized PHMS dopamine hydrochloride, and finally add 0.1% NaOH solution relative to the mass of epoxy-functionalized PHMS, heat and reflux at 40°C for 6 hours, then add 0.01 times the mass of epoxy functionalized PHMS Functionalized ethylenediamine with PHMS quality was heated and refluxed at 40°C for 6 hours. After the reaction was completed, the whole solution was concentrated to 1/10 of the original volume by rotary evaporation to obtain a black blue and white color for inkjet printing. Water-based dispersant for colorants.

In the dispersant thus prepared, the molar ratio of DOPA to EDA is 1.0:1.4, and the molar ratio of DOPA to PEGDMA is 1.0:0.16˜1.0:2.0.

Example 2

A kind of black blue and white pigment aqueous dispersant for inkjet printing is prepared by the following method:

(1) Get PHMS (molecular weight is 2000Da, hydrogen substitution degree 60%) and GMA are dissolved in toluene, wherein the mass ratio of PHMS and GMA is 1:10, then add platinum catalyst, wherein the relative mass fraction of catalyst and epoxy unit 0.03%, then use inert gas bubbling to deoxygenate for 20 minutes, heat and reflux at 60°C for 6 hours, after the reaction is completed, pour 2 times the volume of ethanol to wash, and then let it stand for 20 minutes to separate the liquid, collect the lower liquid, and store it at room temperature Vacuum drying to obtain epoxy-functionalized PHMS.

(2) Get a certain amount of epoxy-functionalized PHMS, dissolve it in dimethylacetamide, the mass concentration after dissolving is 20%, add 4 times the dicarboxypolyethylene glycol of the epoxy-functionalized PHMS quality, Then add 0.1 times the mass of epoxy-functionalized PHMS dopamine hydrochloride, and finally add 0.5% NaOH solution relative to the mass of epoxy-functionalized PHMS, heat and reflux at 60 ° C for 4 hours, and then add 0.05 times the mass of epoxy functionalized PHMS Functionalized ethylenediamine with PHMS quality was heated and refluxed at 60°C for 4 hours. After the reaction was completed, the whole solution was concentrated to 1/5 of the original volume by rotary evaporation to obtain a black blue flower for inkjet printing. Water-based dispersant for colorants.

The dispersants thus prepared had a molar ratio of DOPA to EDA of 1.0:2.9 and a molar ratio of DOPA to PEGDMA of 1.0:0.52.

Example 3

A kind of black blue and white pigment aqueous dispersant for inkjet printing is prepared by the following method:

(1) Get PHMS (molecular weight is 5000Da, hydrogen substitution degree 80%) and GMA are dissolved in toluene, wherein the mass ratio of PHMS and GMA is 1:5, then add platinum catalyst, wherein the relative mass fraction of catalyst and epoxy unit After the reaction is completed, pour 0.5 to 5 times the volume of isopropanol to wash, then let it stand for 10 minutes to separate the liquid, and collect The lower liquid was vacuum-dried at room temperature to obtain epoxy-functionalized PHMS.

(2) Get a certain amount of epoxy-functionalized PHMS, dissolve it in dichloromethane, and the mass concentration after dissolving is 30%, add 8 times the dicarboxypolyethylene glycol of epoxy-functionalized PHMS quality, then add 0.3 times the mass of epoxy-functionalized PHMS dopamine hydrochloride, finally add 1.0% NaOH solution relative to the mass of epoxy-functionalized PHMS, heat and reflux at 80°C for 2 hours, then add 0.1 times the mass of epoxy-functionalized PHMS Ethylenediamine of PHMS quality was heated and refluxed at 80°C for 2 hours. After the reaction was completed, the entire solution was concentrated to 2/5 of the original volume by rotary evaporation to obtain a black blue and white coloring material for inkjet printing. Aqueous dispersant.

The dispersant thus prepared had a molar ratio of DOPA to EDA of 1.0:3.6 and a molar ratio of DOPA to PEGDMA of 1.0:1.2.

Example 4

A kind of black blue and white pigment aqueous dispersant for inkjet printing is prepared by the following method:

(1) Get PHMS (molecular weight is 10000Da, hydrogen substitution degree 80%) and GMA are dissolved in benzene, wherein the mass ratio of PHMS and GMA is 1:1, then add platinum catalyst, wherein the relative mass fraction of catalyst and epoxy unit 0.1%, then use inert gas bubbling to deoxygenate for 60 minutes, heat and reflux at 100°C for 2 hours, after the reaction is completed, pour 5 times the volume of n-hexane to wash, and then stand for 5 minutes to separate the liquid, collect the lower layer liquid, Vacuum drying at room temperature to obtain epoxy-functionalized PHMS.

(2) Get a certain amount of epoxy-functionalized PHMS, dissolve it in chloroform, and the mass concentration after dissolving is 40%, add 10 times the dicarboxypolyethylene glycol of epoxy-functionalized PHMS quality, then add 0.5 times the mass of epoxy-functionalized PHMS dopamine hydrochloride, finally add 2.0% NaOH solution relative to the mass of epoxy-functionalized PHMS, heat and reflux at 80°C for 0.5 hours, then add 0.2 times the mass of epoxy-functionalized PHMS Ethylenediamine of PHMS quality was heated and refluxed at 80°C for 0.5 hours. After the reaction was completed, the entire solution was concentrated to 1/2 of the original volume by rotary evaporation to obtain a black blue and white coloring material for inkjet printing. Aqueous dispersant.

The dispersants thus prepared had a molar ratio of DOPA to EDA of 1.0:4.7 and a molar ratio of DOPA to PEGDMA of 1.0:1.8.

Example 5

An application method of a black blue and white pigment water-based dispersant for inkjet printing is realized by the following technical means:

(1) The dispersant is added to the black and blue color pigment, wherein the dispersant accounts for 10% of the mass fraction of the pigment, and distilled water is added, wherein the total mass of the pigment and the dispersant accounts for 30% of the mass fraction in the system, The stirrer speed was set to 60 rpm, and a pre-stirring operation was performed for 15 minutes.

(2) Add the pre-stirred mixture into the ball mill, set the rotating speed to 6000 rpm, and ball mill for 150 minutes. During the ball milling process, use dilute lye to adjust the pH value of the mixture to 7.0 continuously and slowly to obtain a Black cyan ink for inkjet printing.

Example 6

An application method of a black blue and white pigment water-based dispersant for inkjet printing is realized by the following technical means:

(1) The dispersant is added to the black and blue color pigment, wherein the dispersant accounts for 15% of the mass fraction of the pigment, and distilled water is added, wherein the total mass of the pigment and the dispersant accounts for 40% of the mass fraction in the system, The speed of the stirrer was set to 120 rpm, and a pre-stirring operation was performed for 60 minutes.

(2) Add the pre-stirred mixture into the ball mill, set the rotating speed to 8000 rpm, and ball mill for 90 minutes. During the ball milling process, use dilute lye to adjust the pH value of the mixture slowly to 7.0 to obtain a Black cyan ink for inkjet printing.

Example 7

An application method of a black blue and white pigment water-based dispersant for inkjet printing is realized by the following technical means:

(1) The dispersant is added to the black and blue color pigment, wherein the dispersant accounts for 20% of the mass fraction of the pigment, and distilled water is added, wherein the total mass of the pigment and the dispersant accounts for 40% of the mass fraction in the system, The stirrer speed was set to 180 rpm, and a pre-stirring operation was performed for 90 minutes.

(2) Add the pre-stirred mixture into the ball mill, set the rotating speed to 10000 rpm, and ball mill for 60 minutes. During the ball milling process, use dilute lye to adjust the pH value of the mixture to 8.0 continuously and slowly to obtain a Black cyan ink for inkjet printing.

Example 8

An application method of a black blue and white pigment water-based dispersant for inkjet printing is realized by the following technical means:

(1) The dispersant is added to the black blue color color material, wherein the dispersant accounts for 20% of the mass fraction of the color material, and distilled water is added, wherein the total mass of the color material and the dispersant accounts for 50% of the mass fraction in the system, The speed of the stirrer was set at 240 rpm, and a pre-stirring operation was performed for 120 minutes.

(2) Add the pre-stirred mixture into the ball mill, set the rotating speed to 12000 rpm, and ball mill for 30 minutes. During the ball milling process, use dilute lye to adjust the pH value of the mixture slowly to 9.0 to obtain a Black cyan ink for inkjet printing.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (7)

1. the black blue and white pigment aqueous dispersion agent that is used for ink-jet printing is characterized in that, the structural formula of the graft copolymer that structure has as shown below is PHMS- g- (DOPA- r -EDA- r -PEGDMA); Specifically for: Among them, g represents grafting, r represents random distribution; PHMS represents units made from hydrogen-containing polysiloxane and glycidyl methacrylate; DOPA represents dopamine units; EDA represents ethylenediamine units; PEGDMA represents dicarboxylic acid Polyethylene glycol unit, the weight average molecular weight is 2000~20000 Da. 2. the black blue and white pigment aqueous dispersant for inkjet printing according to claim 1, is characterized in that, the mol ratio of DOPA and EDA is 1.0:1.0～1.0:5.0, and the mol ratio of DOPA and PEGDMA is 1.0 :0.1~1.0:2.0. 3. the preparation method of the black blue and white pigment aqueous dispersion agent that is used for ink-jet printing described in any one of claim 1～2, is characterized in that, comprises the steps: (1) Dissolve hydrogen-containing polysiloxane and glycidyl methacrylate in solvent A, wherein the mass ratio of hydrogen-containing polysiloxane and glycidyl methacrylate is 1:1~1:15, and then Add platinum catalyst, wherein the relative mass fraction of platinum catalyst and epoxy unit is 0.01%~0.1%; then use inert gas to deoxygenate by bubbling for 10~60 minutes, heat and reflux at 40~100 ^o C for 2~12 hours, and react After the completion, pour 0.5~5 times the volume of solvent B to wash, and then let it stand for 5~30 minutes to separate the liquid, collect the lower layer liquid, and dry it in vacuum at room temperature to obtain epoxy functionalized hydrogen-containing polysiloxane; (2) Take a certain amount of epoxy-functionalized hydrogen-containing polysiloxane, dissolve it in solvent C, and the dissolved mass concentration is 10%~40%, add 1~10 times of epoxy-functionalized Dicarboxylic acid polyethylene glycol of siloxane quality, then add dopamine hydrochloride 0.05~0.5 times the mass of epoxy-functionalized hydrogen-containing polysiloxane, and finally add relative epoxy-functionalized hydrogen-containing polysiloxane NaOH solution with an alkane mass of 0.1%~2.0%, heated and refluxed at 40~80 ^o C for 0.5~6 hours, and then added ethylenediamine 0.01~0.2 times the mass of epoxy-functionalized hydrogen-containing polysiloxane, Continue to heat and reflux at 40~80 ^o C for 0.5~6 hours. After the reaction is complete, concentrate the entire solution to 1/10~1/2 of the original volume by rotary evaporation to obtain a water-based black blue and white colorant for inkjet printing. Dispersant. 4. The preparation method of the black blue and white pigment aqueous dispersant for inkjet printing according to claim 3, characterized in that, the molecular weight of the hydrogen-containing polysiloxane described in step (1) is 500~10000 Da, the degree of hydrogen substitution is 40%~80%. 5. the preparation method of the black blue and white pigment aqueous dispersant that is used for ink-jet printing according to claim 3, is characterized in that, described solvent A is a kind of in xylene, toluene, benzene. 6. the preparation method of the black blue and white pigment aqueous dispersant that is used for inkjet printing according to claim 3, is characterized in that, described solvent B is the one in methyl alcohol, ethanol, Virahol, n-hexane . 7. the preparation method of the black blue and white pigment aqueous dispersion agent that is used for inkjet printing according to claim 3, is characterized in that, the solvent C described in step (2) is dimethyl formamide, dimethyl One of acetamide, benzene, toluene, xylene, methylene chloride, and chloroform.