Antistatic water-based ink as well as preparation method and application thereof

Abstract

The invention discloses antistatic water-based ink, and belongs to the field of ink. The antistatic water-based ink comprises 40-80 parts of waterborne polyurethane emulsion; 5 to 50 parts of a carbon nitride nanoparticle dispersion liquid; 0.4-5 parts of a proper amount of other auxiliary agents; the carbon nitride nano particles are oxygen doped nitrogen carbide nano particles; the invention also discloses a preparation method of the ink. The preparation method comprises the following steps: S1, preparing the waterborne polyurethane emulsion; s2, preparing an oxygen-doped nitrogen carbide nano particle dispersion liquid; s3, mixing the prepared waterborne polyurethane emulsion, the prepared nitrogen carbide nanoparticle dispersion liquid, a flatting agent, a wetting agent, a defoaming agent and a thickening agent to prepare the antistatic waterborne ink.

Description

Technical Field

[0001] The invention relates to antistatic water-based ink. Background Art

[0002] Graphite is often used as an antistatic agent for inks due to its low price and good conductivity. However, since graphite is black, it is mostly used in black ink systems and is not suitable for other color systems. Carbon nitride has a two-dimensional layered structure similar to graphite, has good conductivity, and is lighter in color, which has little effect on the color of the ink system. It is expected to be used to prepare antistatic inks of various colors. In addition, similar to graphite, conventionally structured carbon nitride has poor dispersibility in aqueous solutions, which limits its application in inks, resulting in limited improvement in the antistatic ability of inks and also reduces other properties of inks. Summary of the invention

[0003] The purpose of the present invention is to solve the problems in the prior art and disclose an antistatic water-based ink, which comprises, by weight:

[0004] Water-based polyurethane emulsion: 40-80 parts;

[0005] Carbon nitride nanoparticle dispersion: 5-50 parts;

[0006] Other appropriate additives: 0.4-5 parts.

[0007] The carbon nitride nanoparticles are oxygen-doped carbonized nitrogen nanoparticles.

[0008] In some preferred embodiments, the other appropriate amount of auxiliary agents include:

[0009] Leveling agent: 0.1-1 part;

[0010] Wetting: 0.1-1 part;

[0011] Defoaming agent: 0.1-1 part;

[0012] Thickener 0.1-2 parts.

[0013] The present application also discloses a method for preparing an antistatic water-based ink, the steps of which are as follows:

[0014] S1: preparing aqueous polyurethane emulsion;

[0015] S2: preparing oxygen-doped carbonized nitrogen nanoparticle dispersion;

[0016] S3: The prepared aqueous polyurethane emulsion, carbonized nitrogen nanoparticle dispersion, leveling agent, wetting agent, defoaming agent, and thickener are mixed to prepare an antistatic aqueous ink.

[0017] In some preferred embodiments, the preparation method of the aqueous polyurethane emulsion is as follows: polyethylene glycol, 2,2-dihydroxymethylpropionic acid, isophorone diisocyanate and dibutyltin dilaurate are added to a reaction container, and the temperature is controlled to react under stirring; then, dihydroxy-terminated polypropylene adipate is added, the temperature is controlled to continue the reaction, and then trihydroxypropane is added to control the temperature to continue the reaction; after the reaction is completed, the temperature is lowered, an appropriate amount of triethylamine is added for neutralization, the temperature is continued to be lowered, a certain amount of distilled water is slowly added under high-speed and vigorous stirring for dispersion, and an appropriate amount of ethylenediamine is added for chain extension to obtain an aqueous polyurethane emulsion.

[0018] In some preferred embodiments, the raw materials for preparing the aqueous polyurethane emulsion are as follows:

[0019] Polyethylene glycol: 20-70 parts;

[0020] 2,2-dimethylolpropionic acid: 0.1-2 parts;

[0021] Isophorone diisocyanate: 1-15 parts;

[0022] Dibutyltin dilaurate: 0.1-1.0 parts;

[0023] Dihydroxy-terminated poly(propylene adipate): 20-70 parts;

[0024] Trihydroxypropane: 0.01-0.1 parts;

[0025] Triethylamine: 0.1-2 parts;

[0026] Ethylenediamine: 0.1-2 parts.

[0027] In some preferred embodiments, the preparation method of the oxygen-doped carbon nitride nanoparticle dispersion is as follows:

[0028] Melamine is placed in a reaction furnace and reacted at a controlled temperature without nitrogen protection; after the reaction is completed, the temperature is lowered to room temperature to obtain a solid powder; then, the obtained powder is ultrasonically dispersed in an aqueous solution of sodium dodecylbenzene sulfonate to obtain a suspension.

[0029] In some preferred embodiments, the reaction furnace is a muffle furnace.

[0030] The application also discloses the application of the antistatic water-based ink in a PET substrate. DETAILED DESCRIPTION

[0031] The present invention is described in detail below.

[0032] 1. Preparation of water-soluble polyurethane emulsion.

[0033] In a four-necked flask equipped with a stirrer, a condenser and a thermometer, a certain amount of polyethylene glycol, 2,2-dihydroxymethylpropionic acid, isophorone diisocyanate and dibutyltin dilaurate were added at room temperature, and the temperature was slowly raised to 80°C under stirring, and the reaction was carried out at a constant temperature for 2 hours; then, a measured amount of dihydroxy-terminated poly(propylene adipate) was added, and the reaction was continued at 80°C for 4 hours; then, a measured amount of trihydroxypropane was added, the temperature was raised to 100°C, and the reaction was continued for 3 hours; after the reaction was completed, the temperature was lowered to 60°C, an appropriate amount of triethylamine was added, and the mixture was neutralized and stirred for 30 minutes, and the temperature was further lowered to about 30°C, and a certain amount of distilled water was slowly added under high-speed and vigorous stirring.

[0034] Distilled water is used for dispersion, and an appropriate amount of ethylenediamine is added for chain extension to obtain an aqueous polyurethane emulsion with a solid content of about 40%. The specific embodiment formula of the aqueous polyurethane emulsion is shown in Table 1:

[0035] Table 1

[0036]

[0037]

[0038] In the table, 5000 and 2000 represent the corresponding polymer molecular weights of 5000 and 2000; the mass units are all g.

[0039] 2. Preparation of carbonized nitrogen nanoparticle dispersion.

[0040] 1. Preparation of oxygen-doped carbonized nitrogen nanoparticle dispersion (experimental group): First, weigh 100.0g of melamine and put it into a muffle furnace. In the absence of nitrogen protection, heat it to 400°C and react at a constant temperature for 8h. After the reaction is completed, the temperature is lowered to room temperature to obtain a solid powder. After that, the obtained powder is ultrasonically dispersed in an aqueous solution containing 1000.0mL of 0.1g / ml sodium dodecylbenzene sulfonate to obtain a suspension. After the ultrasound stops, no powder precipitation is found within 1 week. Ultrasonicate for 1h before use.

[0041] 2. Preparation of conventional carbonized nitrogen nanoparticle dispersion (control group): First, weigh 100.0g of melamine and put it into a muffle furnace. Under nitrogen protection, heat to 400°C and react at constant temperature for 8h. After the reaction is completed, the temperature is lowered to room temperature to obtain a solid powder. After that, the obtained powder is ultrasonically dispersed in 1000.0mL of 0.1g / ml sodium dodecylbenzene sulfonate aqueous solution. After the ultrasound stops, the powder is quickly precipitated and ultrasonicated for 1h before use.

[0042] 3. Preparation of water-based ink resin

[0043] The antistatic water-based ink was prepared by mixing the measured water-based polyurethane emulsion, the carbonized nitrogen nanoparticle dispersion prepared in the experimental group or the control group, the leveling agent, the wetting agent, the defoaming agent and other additives. The prepared antistatic ink was coated on the PET substrate by screen printing, dried in a drying oven at 60°C until the resistance value no longer changed, and tested using a surface resistance tester in accordance with the national standard GB / T 1410-2006.

[0044] Table 2

[0045]

[0046]

[0047] A, B, and C in the table are different water-based resin emulsions, and the mass unit is g.

[0048] IV. Results

[0049] The antistatic properties of the ink are as follows, where the surface resistance is 10 6 -10 9 It has antistatic properties.

[0050] Table 3

[0051]

[0052] It can be seen that the oxygen-doped carbon nitride nanoparticle dispersion can significantly improve the antistatic performance of the ink (more than 2 orders of magnitude) compared to the conventional carbon nitride nanoparticle dispersion (without oxygen doping). At the same time, the change in the ink formula can also significantly affect the antistatic performance (1 order of magnitude).

Claims

1. Antistatic water-based ink, characterized in that: In parts by weight, it comprises: Water-based polyurethane emulsion: 40-80 parts; Carbon nitride nanoparticle dispersion: 5-50 parts; Other appropriate additives: 0.4-5 parts. The carbon nitride nanoparticles are oxygen-doped carbonized nitrogen nanoparticles.

2. The antistatic water-based ink according to claim 1, characterized in that: The other appropriate amount of additives include: Leveling agent: 0.1-1 part; Wetting: 0.1-1 part; Defoaming agent: 0.1-1 part; Thickener 0.1-2 parts.

3. A method for preparing an antistatic water-based ink, characterized in that: Here are the steps: S1: preparing aqueous polyurethane emulsion; S2: preparing oxygen-doped carbonized nitrogen nanoparticle dispersion; S3: The prepared aqueous polyurethane emulsion, carbonized nitrogen nanoparticle dispersion, leveling agent, wetting agent, defoaming agent, and thickener are mixed to prepare an antistatic aqueous ink.

4. The method for preparing the antistatic water-based ink according to claim 3, characterized in that: The preparation method of the waterborne polyurethane emulsion is as follows: polyethylene glycol, 2,2-dihydroxymethyl propionic acid, isophorone diisocyanate and dibutyltin dilaurate are added to a reaction container, and the temperature is controlled to react under stirring; then, dihydroxy-terminated polypropylene adipate is added, the temperature is controlled to continue the reaction, and then trihydroxypropane is added to control the temperature to continue the reaction; after the reaction is completed, the temperature is lowered, an appropriate amount of triethylamine is added for neutralization, the temperature is further lowered, a certain amount of distilled water is slowly added under high-speed and violent stirring for dispersion, and an appropriate amount of ethylenediamine is added for chain extension to obtain the waterborne polyurethane emulsion.

5. The method for preparing the antistatic water-based ink according to claim 4, characterized in that: The raw materials for preparing waterborne polyurethane emulsion are as follows: Polyethylene glycol: 20-70 parts; 2,2-dimethylolpropionic acid: 0.1-2 parts; Isophorone diisocyanate: 1-15 parts; Dibutyltin dilaurate: 0.1-1.0 parts; Dihydroxy-terminated poly(propylene adipate): 20-70 parts; Trihydroxypropane: 0.01-0.1 parts; Triethylamine: 0.1-2 parts; Ethylenediamine: 0.1-2 parts.

6. The method for preparing the antistatic water-based ink according to claim 5, characterized in that: The preparation method of the oxygen-doped carbonized nitrogen nanoparticle dispersion is as follows: Melamine is placed in a reaction furnace and reacted at a controlled temperature without nitrogen protection; after the reaction is completed, the temperature is lowered to room temperature to obtain a solid powder; then, the obtained powder is ultrasonically dispersed in an aqueous solution of sodium dodecylbenzene sulfonate to obtain a suspension.

7. The method for preparing the antistatic water-based ink according to claim 6, characterized in that: The reaction furnace is a muffle furnace.

8. Use of the antistatic water-based ink according to any one of claims 1 to 7 in a PET substrate.

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