CN113354980A

CN113354980A - Universal water-based white ink and preparation method thereof

Info

Publication number: CN113354980A
Application number: CN202110707304.1A
Authority: CN
Inventors: 郝自娟; 闫银凤; 黄晓谨; 王宏磊; 张银宝; 杨武涛; 李勇敢; 袁永浩; 聂夕然
Original assignee: Henan Functional Polymer Membrane Material Innovation Center Co ltd
Current assignee: Henan Functional Polymer Membrane Material Innovation Center Co ltd
Priority date: 2021-06-24
Filing date: 2021-06-24
Publication date: 2021-09-07

Abstract

The invention belongs to the field of novel environment-friendly water-based ink, and relates to universal water-based white ink and a preparation method thereof. The composition is prepared from the following raw materials in parts by weight: modified polyurethane emulsion 1: 25-35 parts of modified polyurethane emulsion 2: 5-15 parts of isopropanol: 3-5 parts of ethanol: 8-13 parts of water: 4-8 parts of titanium dioxide: 35-45 parts of defoaming agent: 0.004 part, leveling agent: 0.01-0.03 part of ED30 matte powder (selenium dioxide): 1-2 parts. The water-based white ink has good printability, is safe and environment-friendly, and has high printing speed, high adhesive force, difficult fading, friction resistance and high peel strength. The ink is applied to PE, PA, OPP/VMCPP and the like, can ensure low cost and simultaneously has the printing speed of more than 150m/min, and is environment-friendly water-based ink.

Description

Universal water-based white ink and preparation method thereof

Technical Field

The invention belongs to the field of novel environment-friendly water-based ink, and relates to universal water-based white ink for surface printing and inner printing packaging and a preparation method thereof.

Background

At present, 90% of enterprises in the thin film flexible packaging industry of China adopt gravure process, most of the enterprises use solvent type ink, but the ink is subject to displacement and limitation under increasingly severe environmental conditions, and even is prohibited in certain economically developed areas. Particularly, in the last two years, a series of policy and regulations for reducing VOCs are introduced by environmental protection departments of provinces and cities in the center and in places of China, a flexible package enterprise has to additionally install an organic waste gas treatment device at the tail end of production, the tail end treatment technology is rapidly developed in the years, but the problem cannot be really solved from the source, and the application of the tail end treatment technology is greatly restricted.

In recent years, with the increasing awareness of environmental protection, research and development of water-based inks have attracted much attention. The water-based ink takes water as a solvent, and the water as the solvent has the advantages of no toxicity, no peculiar smell, no combustion, greatly reduced waste gas discharge amount and reduced environmental pollution, thereby achieving rapid development and having very wide development prospect.

Aqueous polyurethane emulsions (WPU) and aqueous acrylate copolymers (PA) are currently widely used in the market as binders for aqueous inks. Compared with other solvent-based coatings, PU and PA have the advantages of low price, no toxicity, no environmental pollution and wide application in the aspects of leather, adhesives, coatings and the like. Polyurethane has excellent organic solvent resistance, cold resistance, temperature adaptability and elasticity, but has defects in the aspects of gloss retention, water resistance (surface print), adhesive force (surface print), peeling strength (inner print) and the like, and is high in price; the acrylate emulsion has the properties of low price, high mechanical strength, ageing resistance, no yellowing, good water resistance (surface printing), strong adhesive force (surface printing) and high peel strength (inner printing), but the pH value of the ink prepared from the acrylate is low, an amine reagent needs to be added for adjustment, and the general amine reagent has pungent smell and causes harm to the workshop environment and personnel, so that the improvement is urgently needed.

Disclosure of Invention

Aiming at the problems in the application of the water-based ink and combining the printing characteristics of gravure, the invention aims to provide the water-based white ink for universal surface printing and internal printing packaging and the preparation method thereof.

In order to realize the purpose of the invention, the technical scheme is as follows:

the composition is prepared from the following raw materials in parts by weight:

modified polyurethane emulsion 1: 25 to 35 portions of the total weight of the composition,

modified polyurethane emulsion 2: 5-15 parts of (A) a stabilizer,

isopropyl alcohol: 3-5 parts of (A) a water-soluble polymer,

ethanol: 8-13 parts of (by weight),

water: 4 to 8 portions of

Titanium dioxide: 30-45 parts of (a) a water-soluble polymer,

defoaming agent: 0.004 portion of the above-mentioned raw material,

leveling agent: 0.01 to 0.03 portion of,

ED30 matte powder (selenium dioxide): 1-3 parts.

The modified polyurethane emulsion 1 is modified by polyether, and a plurality of side groups (methyl) are introduced to improve the water resistance, the viscosity is 800-1000, and the acid value is 6.9-7.2; the modified polyurethane emulsion 2 is prepared by introducing carbonate radical into polyurethane molecule, the viscosity is 1000-1200, and the acid value is 7.0-7.5

The method for preparing the universal water-based white ink for surface printing and inner printing packaging comprises the following specific steps:

1) adding the modified polyurethane emulsion 1, isopropanol and ethanol into a reaction vessel according to a certain proportion, then adding a defoaming agent, and stirring for dissolving;

2) then adding titanium dioxide, water, a leveling agent and ED30 matte powder, and continuing stirring;

3) taking out the reaction product obtained in the step 2), adding the reaction product into a ball mill for grinding, wherein the particle size of white ink obtained after ball milling is 10-15 μm.

4) Adding the ground product obtained in the step 3) into the modified polyurethane emulsion 2, and stirring and mixing.

The principle of the invention is as follows: the modified polyurethane resin 1 has good water resistance and covering power due to the modification of the groups, can resist friction, has good temperature resistance, but has poor adhesive force; the modified polyurethane resin 2 has better dispersibility and adhesion fastness by introducing carbonate, but has no friction resistance and poor temperature resistance. The adhesion force can be greatly improved by adding the modified polyurethane resin 2 into the modified polyurethane resin 1. The defoaming agent can eliminate bubbles and promote better dispersion of the connecting material, and the leveling agent also plays a good role in dispersion and fusion. The ED30 matte powder (selenium dioxide) can play a role in weather resistance, so that the adhesion fastness and the color phase are stable.

The invention has the advantages that: 1. the modified polyurethane resins 1 and 2 are used, so that the two polyurethane resin materials are matched with each other, the excellent performance of the waterborne polyurethane is combined, and the water resistance, the adhesive force and the peel strength of the waterborne polyurethane are improved. 2. The water-based white ink is suitable for surface printing and inner printing of packages, has good printability, is safe and environment-friendly, and is high in printing speed, high in adhesive force, not easy to fade, friction-resistant and high in peel strength. The ink is applied to PE, PA, OPP/VMCPP and the like, can ensure low cost and simultaneously has the printing speed of more than 150m/min, and is environment-friendly water-based ink.

Detailed Description

To better illustrate the invention, the following examples are given:

example 1:

the universal water-based white ink for surface printing and inner printing packaging is prepared from the following raw materials in parts by weight:

modified polyurethane emulsion 1: 30 parts of modified polyurethane emulsion 2: 13 parts of (a) to (b),

isopropyl alcohol: 3 parts of ethanol: 9 parts of water: 5 parts, titanium dioxide: 37 parts of (a) to (b),

defoaming agent: 0.004 part, leveling agent: 0.03, ED30 matte powder (selenium dioxide): 2.966 parts.

1) Adding the modified polyurethane emulsion 1, isopropanol and ethanol into a reaction vessel according to a certain proportion, then adding a defoaming agent, and dispersing and stirring for 20 minutes by using a high-speed dispersion machine for full dissolution;

2) then adding titanium dioxide, water, a leveling agent and ED30 matte powder (selenium dioxide), and continuing stirring for 50 minutes;

3) taking out the reaction product obtained in the step 2), adding the reaction product into a ball mill for grinding for 60 minutes,

the particle size of the white ink obtained was 10 μm.

Example 2:

modified polyurethane emulsion 1: 33 parts, modified polyurethane emulsion 2: 12 parts of (a) to (b),

isopropyl alcohol: 4 parts, ethanol: 10 parts of water: 6 parts of titanium dioxide: 32 parts of (a) to (b),

defoaming agent: 0.004 part, leveling agent: 0.016, ED30 matte powder (selenium dioxide): 2.98 parts.

The preparation method is the same as example 1.

Application example

The universal water-based white ink for surface printing and inner printing packaging has the following test indexes in practical application:

1. the drying speed is high, and the printing speed reaches 180 m/min;

2. the adhesive force is good: 3M adhesive tape detection shows that the PE film prepared by the water-based white ink for universal surface printing and inner printing packaging does not lose ink, and the PE film prepared by the solvent-based white ink has ink loss;

3. friction resistance: the PE film prepared by the water white ink for the universal surface printing and inner printing packaging is subjected to 30 g/eraser test, and is repeatedly erased for 1 ten thousand times, and the characters and the patterns have no obvious color difference change; clearly identifiable without falling off and broken lines;

PE film made with solvent white ink: the characters and the patterns have obvious color difference change after being repeatedly erased for 1 thousand times; it was recognized that there was little separation and disconnection.

4. The peel strength is high: the average value of the peel strength at 180 ℃ of the OPP/VMCPP composite film prepared by the water-based white ink for the universal surface printing and inner printing packaging reaches 1.33N; the average value of the peeling strength at 180 ℃ of the OPP/VMCPP composite film prepared from the solvent type white ink reaches 1.03N.

Claims

1. The water-based printing white ink is characterized by being prepared from the following raw materials in parts by weight:

modified polyurethane emulsion 2: 5-15 parts of (A) a stabilizer,

isopropyl alcohol: 3-5 parts of (A) a water-soluble polymer,

ethanol: 8-13 parts of (by weight),

water: 4-8 parts of (A), by weight,

titanium dioxide: 30-45 parts of (a) a water-soluble polymer,

defoaming agent: 0.004 portion of the above-mentioned raw material,

leveling agent: 0.01 to 0.03 portion of,

ED30 matte powder: 1-3 parts;

the modified polyurethane emulsion 1 is polyether modified polyurethane, a plurality of side methyl groups are introduced into the molecule, the viscosity is 800-1000, and the acid value is 6.9-7.2; the modified polyurethane emulsion 2 is prepared by introducing carbonate radical into polyurethane molecule, the viscosity is 1000-1200, and the acid value is 7.0-7.5.