Development of the hottest water-based ink and its

The development of water-based ink and the surface tension value of ink (2)

2 results and discussion

2.1 colorant

the colorants commonly used in the preparation of ink are dyes and pigments. Using dyes as colorants has the advantages of convenient preparation, low cost, good stability, bright color and not easy to block, but the ink has poor water fastness and light fastness; Using pigments as colorants, the ink has excellent light resistance, water resistance, heat resistance and oxidation resistance, but the pigments are easy to aggregate, Poor ink stability [31. Dyes are commonly used as colorants for water-based inks, including direct dyes and acid dyes. At present, there is no special dye for inks at home and abroad. The commercially available dyes cannot be directly used to prepare inks due to the high content of metal ions and need further treatment. Here, membrane separation technology is used to further treat the dyes. Table 1 shows the content of the main metal ions of the dyes treated by membrane separation technology and the special dyes for inks of foreign ball pen factories. From the table It can be seen that after further treatment by membrane separation technology, the content of main metal ions in the dye has been very low, which can meet the requirements of water-based ink. The prepared ink has good stability and fluent writing

Table 1 content of main metal ions of dye (PPM)

table content of main metals of dye

element CA CD Cu Fe K Mg Mn Na Pb SR zn

preparation of dye 158.7090.5533.7155.332.38

imported ink dye 391.10 2.54 216.543.1 641 3.97 88170 5.95 17.5 0.53

2.2 solvent

in addition to water, a certain amount of water-soluble organic solvent is often added to the ink as a solvent, It mainly plays the role of wetting, preventing the ink from drying due to water evaporation during long-term storage, affecting the writing performance of the ink, and making the ink have good anti drying and decapping properties. In addition, the water-soluble organic solvent can also prevent the ink from freezing and lubricating at low temperature. Commonly used water-soluble organic solvents include ethylene glycol, glycerol, diethylene glycol, etc., and the amount is often% of the total amount of ink [1]. Table 2 shows the relationship between solvent dosage and ink performance. It can be seen from the table that the classification of the friction and wear testing machine with the amount of solvent and the precautions in operation increase, and the viscosity of the ink increases. When the amount of solvent exceeds 35%, the writing performance of the ink becomes poor, and it is easy to break the lines, and the ink is difficult to dry, easy to feather and stain the paper and other articles. At the same time, it will increase the cost of the ink, so the solvent content should not be too large. However, the solvent content should not be too small, otherwise the ink is volatile, not suitable for long-term storage, and also affects the writing fluency. Therefore, the solvent content should be% as appropriate

Table 2 Relationship between solvent dosage and ink performance

table2 solvent concentration vs.ink properties

solvent content (%) 15253545

viscosity (CP) 2.85 4.02 6.27 9.80

poor hatchability good good good good

ink drying speed is fast and slow

permeability no paper penetration no paper penetration slightly paper penetration slightly paper penetration slightly anti eclosion good slight eclosion slightly eclosion

Table 3 Relationship between solvent and ink performance and unique important technical skills and professional knowledge

table3 solvent vs.inkproperties

solvent glycol diethylene glycol glycerol glycol glycol Glycol propanol compound solvent (13:12)

viscosity (CP) 3.13 4.02 9.91 6.94

ink drying speed is fast and slow

slightly permeable, no paper, no paper, no paper

permeable, no leakage, no leakage, no leakage

smooth and fluent writing performance, smooth and smooth flow, sharp and slightly broken line

table 3 shows the relationship between different solvents and ink performance when the solvent dosage is 25%. It can be seen from the table that when ethylene glycol is used as solvent, the ink viscosity is low, resulting in leakage, penetration and other problems; When glycerin is used as solvent, the ink viscosity is large and the drying is slow, resulting in problems such as broken lines and ink stains that are difficult to dry and stain the paper; When using glycol and glycerol compound solvent, the ink writing performance is poor. 4. Building foundation, marking off; When diethylene glycol is used as solvent, the overall performance of the ink is good, so diethylene glycol is used as solvent here

2.3 main physical properties of ink

the main physical properties of ink include viscosity, surface tension, pH value and specific gravity. Viscosity will seriously affect the writing performance of ink. Low viscosity ink can write fluently, but it will bring problems such as penetration, illegibility and leakage. High viscosity can avoid penetration and ink spots from the pen tip, but it is easy to produce problems such as broken lines and blocked pen heads. The viscosity of aqueous ink is usually 2-8cp. Surface tension mainly affects the permeability of ink in paper and other media, and also affects the moisture retention and stability of ink. The surface tension is small, the ink is easy to penetrate into the paper or other media, and the ink dries quickly; The surface tension is large, the ink permeability to the medium is small, and the ink is too slow to write on the paper. The surface tension of water-based ink is usually 25-40mn/m

the pH value of the ink will affect the solubility and stability of the dye and the corrosiveness of the ink to the pen head. Too high or too low pH value will accelerate the corrosion of the ink to the pen head

Table 4 main physical properties of inks

table4 physical properties index of ink

item viscosity (CP) surface tension (Mn/M) pH specific gravity (g/M1)

prepared inks 4.0232.7 9.32 1.05

national treasure inks 4.4387.6 1.10

Table 4 is the main physical properties of prepared inks. It can be seen from the table that the main physical performance indexes of the prepared ink are within the required range

2.4 ink writing performance

table 5 will build Ningbo into an international first-class and domestic leading new material innovation center, which is the writing performance of prepared ink and imported ink. It can be seen from the table that the main writing performance of the prepared ink has approached or reached that of imported ink, Meet the Chinese light industry standard [1) and Japanese industrial standard [2) for water-based ball point pen.

table 5 ink writing properties of ink

project preparation ink imported ink ① imported ink ②

writing performance ≥ 400m ≥ 400m

ink output (mg/M) 1.159 1.127 1.237

drying time (s) 555

good copying performance

permeability no paper no paper no paper no paper no paper

hat removal no slip no slip no slip

project preparation ink import ink import ink

water resistance visual inspection of writing lines visual inspection of writing lines visual inspection of writing lines

ethanol resistance visual inspection of writing lines visual inspection of writing lines visual inspection of writing lines visual inspection of writing lines

Salt and acid resistance visible writing lines visible writing lines visible ammonia water resistance visible writing lines invisible writing lines no writing lines slightly better eclosion resistance slightly better eclosion conclusion

1) dyes can be used as colorants for water-based inks after membrane separation technology. The prepared inks are stable and have good writing performance

2) when diethylene glycol is used as solvent, the ink has good properties, and the appropriate dosage is 20-35%

3) the main physical properties of the prepared ink are within the required range

4) the main writing performance of the prepared ink has approached or reached that of the imported ink, and meets the Chinese light industry standard and the Japanese industry standard for water-based ball pen

reference

[1] water-based ballpoint pen and its refill, light industry standard of the people's Republic of China (discussion draft).

[2] water-based ballpoint pen and its refill, Japanese industrial standard.Jis s 6054--2000.

[3] a direct addition ink for ballpoint pen,.X.

[4] water-based ink composition,.5.

[5] pseudoplastic water-based ink for ballpoint pen, .8.

information source: fine chemicals in the 21st century