A heat-sensitive water-based liquid ink and a method for preparing the same

Abstract

The application discloses a kind of heat-sensitive water-based direct liquid ink and its preparation method, including the following weight percentage of raw materials are made: 78.17% deionized water, 16% humectant, 0.02% filler, 5% microcapsule color paste, 0.1% preservative, 0.5% main dispersant, 0.1% auxiliary dispersant, 0.1% ph regulator, 0.01% thickener.The humectant is glycerol and ethylene glycol, wherein the mass ratio of glycerol and ethylene glycol is 3:1.The filler is acrylic resin;The main dispersant is alkyl ammonium salt;Alkyl ammonium salt is dodecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium bromide or octadecyl trimethyl ammonium bromide.The auxiliary dispersant is anionic surfactant;Anionic surfactant is sodium dodecyl sulfate.By modifying HEC, and at the same time as a suspending agent, help pigments or other solid ingredients evenly suspended in ink, to prevent precipitation and agglomeration.Through its dispersion, it can be ensured that the ink still remains uniform and stable after long-term storage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of direct liquid ink, in particular to a kind of heat-sensitive water-based direct liquid ink and preparation method thereof. BACKGROUND

[0002] Direct liquid water-based pen is more and more favored in stationery writing pen due to its smooth writing, suitable hand feeling, and less prone to broken line. The ink matched with it is mostly based on ethylene glycol as main solvent, which is toxic to animals and harmful to the body in long-term use. In addition, direct liquid water-based ink is divided into water-based dye type ink and water-based pigment type ink. Although the latter has more water-resistant and sun-resistant writing, long storage time, its pigment is mainly organic compound, and the use of organic solvent has strong volatility, which is not conducive to the health of children who use it all year round to absorb volatile organic gases. The water-based dye type ink can improve its safety performance by selecting environmentally friendly dyes, but its storage durability, dry resistance and leakage resistance are poor. Therefore, it is necessary to develop a direct liquid ink that can ensure the safe use of water-based ink while improving its performance.

[0003] With the development of pigment microcapsule technology, it is widely used in printing, textile and ink industry. Heat-sensitive color-changing ink controls color change by temperature difference, which has the characteristics of color development at room temperature, complete color fading at high temperature (65℃) and complete color development at low temperature (-18℃) compared with traditional ink.

[0004] Its preparation process is different from that of traditional ink. First, heat-sensitive color-changing color paste is prepared, then modified, followed by subsequent production, and finally heat-sensitive color-changing ink is prepared. The heat-sensitive color-changing color paste is a microcapsule system with large particle size, and the average particle size is also 1-3 microns, which is much larger than the nanoscale of ordinary pen ink. Due to the large particle size, the heat-sensitive color-changing pen ink system has poor stability, easy to block pen tip, and prone to writing single side, hollow and broken line, which seriously affects the writing feeling and performance and reduces the quality of ink.

[0005] The patent technology "a pigment type neutral ink and its production method" (publication number: CN103333552) provides a pigment type neutral ink, which is a slightly alkaline ink suitable for neutral pen structure. However, it is not suitable for pen in terms of composition and ink performance.

[0006] Therefore, the inventor has improved the existing technology and deficiencies, and provided a heat-sensitive water-based direct liquid ink, in order to achieve the purpose of having more practical value. SUMMARY

[0007] In order to solve the problems mentioned in the background art, the present application provides a kind of heat-sensitive water-based direct liquid ink.

[0008] To achieve the above object, the present application adopts the following technical solutions:

[0009] A kind of heat-sensitive water-based direct liquid ink, including the following raw materials made with percentage by weight:

[0010] 75-80% deionized water, 10-20% humectant, 0.02-0.05% filler, 3-7% microcapsule color paste, 0.1-0.3% preservative, 0.3-0.7% main dispersant, 0.1-0.5% auxiliary dispersant, 0.1-0.5 ph regulator, 0.01-0.05% thickening agent.

[0011] Preferably, including the following raw materials made with percentage by weight: 78.17% deionized water, 16% humectant, 0.02% filler, 5% microcapsule color paste, 0.1% preservative, 0.5% main dispersant, 0.1% auxiliary dispersant, 0.1% ph regulator, 0.01% thickening agent.

[0012] Preferably, the humectant is glycerol and ethylene glycol, and the mass ratio of glycerol and ethylene glycol is 3:1.

[0013] Preferably, the filler is acrylic resin.

[0014] The main dispersant is alkyl ammonium salt; the alkyl ammonium salt is dodecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium bromide or octadecyl trimethyl ammonium bromide.

[0015] The auxiliary dispersant is an anionic surfactant; the anionic surfactant is sodium dodecyl sulfate.

[0016] The microcapsule color paste is 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide (CVL).

[0017] The preservative is 2-butyl-1,2-benzisothiazolin-3-one.

[0018] The ph regulator is triethanolamine.

[0019] Preferably, the thickening agent is modified hydroxyethyl cellulose, and the preparation method of the modified hydroxyethyl cellulose comprises the following steps:

[0020] S1, add glacial acetic acid, LiCl and N,N-dimethylacetamide (DMAc) to construct a LiCl / DMAc system in a container, and then add hydroxyethyl cellulose and stir until completely dissolved;

[0021] S2, add chitosan, anhydride and anhydrous sodium acetate, and use microwave radiation to control the reaction.

[0022] S3, after the reaction, the reaction was terminated with deionized water and concentrated hydrochloric acid, and the reaction was fully shaken;

[0023] S4, the reaction was slowly poured into excess 50-70℃ deionized water and stirred to obtain white flocculent; after filtration, washed with deionized water until pH> 5, the washed product was placed in an oven to dry and ground to obtain modified hydroxyethyl cellulose.

[0024] Preferably, the acid anhydride is one or more of acetic anhydride, monochloroformic anhydride, propionic anhydride, succinic anhydride.

[0025] Preferably, the mass ratio of LiCl and N,N-dimethylacetamide (DMAc) in S1 is 1:1.1-1.3.

[0026] Preferably, the temperature is controlled by microwave radiation in S2 for 20-60min.

[0027] Preferably, the washed product is placed in an oven at 85-90℃ for 3-5h in S4.

[0028] When hydroxyethyl cellulose is dissolved in LiCl / DMAc system, LiCl is first mixed with DMAc and ionized to form anions and cations, in which free Cl- and hydroxyl groups on hydroxyethyl cellulose form hydrogen bonds to break the hydrogen bond network of original cellulose, and Li+ forms a cationic complex [Li(DMAc)]+ with DMAc, which promotes the penetration of solvent into the crystal region of hydroxyethyl cellulose by charge effect and volume effect, thereby promoting the homogeneous solvent dissolution of hydroxyethyl cellulose.

[0029] Chitosan is insoluble in water, alkali and general organic solvents, but chloroalkane acid can react with the hydroxyl or amino groups on chitosan to obtain the corresponding carboxylated chitosan derivatives, which have good water solubility and green environmental protection. At the same time, the hydroxyl and amino groups on chitosan can undergo acylation reaction with acid anhydride to generate derivatives with N-acylated structure and O-acylated structure, which improves the solubility of the derivatives and promotes the further dissolution of chitosan.

[0030] Chitosan and its derivatives have biocompatibility and biodegradability, and have significant antibacterial properties, good inhibition effect on Escherichia coli, Pseudomonas fluorescens, Staphylococcus aureus, Bacillus subtilis, etc., and can prevent the growth of bacteria in ink during storage and use to some extent. Moreover, chitosan is an excellent natural antibacterial antioxidant for unsaturated fatty acids.

[0031] Hydroxyethyl cellulose (HEC) has good thickening properties, can significantly improve the viscosity of the ink, HEC is a water-soluble non-ionic compound, which has good thickening ability to water, which makes the ink more smoothly through the pen point when in use, while reducing the possibility of dripping and leakage.

[0032] By modifying HEC, and at the same time as a suspending agent, it is helpful for pigments or other solid components to be uniformly suspended in the ink, preventing sedimentation and agglomeration. Through its dispersion effect, it can ensure that the ink remains uniform and stable after long-term storage. And the modified hydroxyethyl cellulose can form a protective film, effectively preventing the pigments and other components in the ink from being oxidized or decomposed, thereby prolonging the service life of the ink and meeting different writing needs.

[0033] A kind of heat-sensitive water-based direct liquid ink and its preparation method further comprise the following steps:

[0034] S1, pre-0.8% modified hydroxyethyl cellulose mixed solution;

[0035] S2, under the condition of stirring, deionized water, glycerol, ethylene glycol, anionic surfactant, alkyl ammonium salt, acrylic resin are added in turn, after stirring for 30min, 3, 3-bis (4-dimethylaminophenyl) -6-dimethylaminophenyl peptide and 2-butyl-1, 2-benzisothiazoline-3-ketone are added, continue to stir for 20-40min;

[0036] S3, sample test viscosity and ph value, respectively with 0.8% hydroxyethyl cellulose mixed solution and triethanolamine adjustment, wherein the viscosity requirement is: 20-30cp, ph value requirement: 7.00-8.30, surface tension: 27-32mN / m.

[0037] Compared with the prior art, the beneficial effects of the present application are:

[0038] The present application modifies hydroxyethyl cellulose, and at the same time uses modified hydroxyethyl cellulose as a suspending agent, which helps pigments or other solid components to be uniformly suspended in the ink, preventing sedimentation and agglomeration. Through its dispersion effect, it can ensure that the ink remains uniform and stable after long-term storage. Modified hydroxyethyl cellulose can form a protective film, effectively preventing the pigments and other components in the ink from being oxidized or decomposed, thereby prolonging the service life of the ink and meeting different writing needs, which has high social use value and application prospect. DETAILED DESCRIPTION

[0039] The technical solutions of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of the present application.

[0040] Unless otherwise specified, the raw materials used in the present application are all from the conventional products purchased in the market. Among them, glycerol CAS No. 56-81-5, ethylene glycol CAS No. 107-21-1, acrylic resin CAS No. 9003-01-4, 3,3-bis (4-dimethylaminophenyl) -6-dimethylaminophenyl CAS No. 1552-42-7, triethanolamine CAS No. 102-71-6, 2-butyl-1,2-benzisothiazolin-3-one CAS No. 4299-07-4, hydroxyethyl cellulose CAS No. 9004-62-0, dodecyl trimethyl ammonium bromide CAS No. 1119-94-4, hexadecyl trimethyl ammonium bromide CAS No. 57-09-0, octadecyl trimethyl ammonium bromide CAS No. 1120-02-1, sodium dodecyl sulfate CAS No. 151-21-3, and all are purchased from Aldrich.

[0041] Preparation Example 1

[0042] The preparation method of the modified hydroxyethyl cellulose comprises the following steps:

[0043] S1, 100 ml of glacial acetic acid, 10 g of LiCl and 11 g of N, N-dimethylacetamide are added to a container to construct a LiCl / DMAc system, and then 20 g of hydroxyethyl cellulose is added and stirred until completely dissolved;

[0044] S2, 20 g of chitosan, 16 g of succinic anhydride and 10 g of anhydrous sodium acetate are added, and microwave radiation is used to control the temperature at 35℃ for 25 min;

[0045] S3, after the reaction is completed, 30 ml of deionized water and 4 ml of concentrated hydrochloric acid are used to terminate the reaction, and the reaction is fully shaken;

[0046] S4, the reaction is slowly poured into excess 50℃ deionized water and stirred to obtain white flocculent material; after being washed with deionized water to pH greater than 5, the washed product is placed in a 85℃ oven for drying for 5 h, and then ground to obtain the modified hydroxyethyl cellulose.

[0047] Preparation Example 2

[0048] The preparation method of the modified hydroxyethyl cellulose comprises the following steps:

[0049] S1, add 100 ml of glacial acetic acid, 10 g of LiCl and 12 g of N, N- dimethylacetamide in a container to build a LiCl / DMAc system, then add 20 g of hydroxyethyl cellulose, and stir until completely dissolved;

[0050] S2, add 20 g of chitosan, 8 g of monochloroformic anhydride, 8 g of propionic anhydride and 10 g of anhydrous sodium acetate, and use microwave radiation to control the temperature at 40°C for 35 min;

[0051] S3, after the reaction is completed, terminate the reaction with 30 ml of deionized water and 4 ml of concentrated hydrochloric acid, and fully shake the reaction product;

[0052] S4, slowly pour the reaction product into excess 60°C deionized water and stir to obtain white flocculent material; after filtration, wash with deionized water until the pH is greater than 5, place the washed product in a 88°C oven to dry for 4 h, and then grind and crush to obtain modified hydroxyethyl cellulose.

[0053] Preparation Example 3

[0054] The preparation method of the modified hydroxyethyl cellulose comprises the following steps:

[0055] S1, add 100 ml of glacial acetic acid, 10 g of LiCl and 13 g of N, N- dimethylacetamide in a container to build a LiCl / DMAc system, then add 20 g of hydroxyethyl cellulose, and stir until completely dissolved;

[0056] S2, add 20 g of chitosan, 8 g of acetic anhydride, 8 g of succinic anhydride and 10 g of anhydrous sodium acetate, and use microwave radiation to control the temperature at 45°C for 40 min;

[0057] S3, after the reaction is completed, terminate the reaction with 30 ml of deionized water and 4 ml of concentrated hydrochloric acid, and fully shake the reaction product;

[0058] S4, slowly pour the reaction product into excess 60°C deionized water and stir to obtain white flocculent material; after filtration, wash with deionized water until the pH is greater than 5, place the washed product in a 90°C oven to dry for 3 h, and then grind and crush to obtain modified hydroxyethyl cellulose.

[0059] Example 1

[0060] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0061] S1, slowly add 0.1 g of the modified hydroxyethyl cellulose prepared in Preparation Example 1 to 12.5 ml of deionized water, and stir until completely dissolved to prepare a 0.8% modified hydroxyethyl cellulose mixture;

[0062] S2, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were sequentially added, and stirring was continued for 20 min;

[0063] S3, viscosity and pH were tested, and 0.8% hydroxyethyl cellulose mixture prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 21 cp, the pH was 7.10, and the surface tension was 28.5 mN / m.

[0064] Example 2

[0065] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0066] S1, 0.2 g of modified hydroxyethyl cellulose prepared in Preparation Example 1 was slowly added to 25 ml of deionized water, and stirring was continued until complete dissolution, and 0.8% modified hydroxyethyl cellulose mixture was prepared;

[0067] S2, under stirring, 760 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 2 g of sodium dodecyl sulfate, 4 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were sequentially added, and stirring was continued for 20 min;

[0068] S3, viscosity and pH were tested, and 0.8% hydroxyethyl cellulose mixture prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 21 cp, the pH was 7.10, and the surface tension was 28.5 mN / m.

[0069] Example 3

[0070] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0071] S1, 0.3 g of modified hydroxyethyl cellulose prepared in Preparation Example 1 was slowly added to 25 ml of deionized water, and stirring was continued until complete dissolution, and 0.8% modified hydroxyethyl cellulose mixture was prepared;

[0072] S2, under stirring, 800 ml of deionized water, 90 g of glycerol, 30 g of ethylene glycol, 3 g of sodium dodecyl sulfate, 5 g of dodecyl trimethyl ammonium bromide, 0.3 g of acrylic resin, 50 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1.5 g of 2-butyl-1,2-benzisothiazolin-3-one were added in sequence, and stirring was continued for 20 min;

[0073] S3, viscosity and pH were tested by sampling, and 0.8% hydroxyethyl cellulose mixture prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 25 cp, the pH was 7.20, and the surface tension was 31.8 mN / m.

[0074] Example 4

[0075] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0076] S1, 0.1 g of modified hydroxyethyl cellulose prepared in Preparation Example 2 was slowly added to 12.5 ml of deionized water, and stirring was continued until complete dissolution, and 0.8% modified hydroxyethyl cellulose mixture was prepared;

[0077] S2, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were added in sequence, and stirring was continued for 20 min;

[0078] S3, viscosity and pH were tested by sampling, and 0.8% hydroxyethyl cellulose mixture prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 21 cp, the pH was 7.20, and the surface tension was 28.3 mN / m.

[0079] Example 5

[0080] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0081] S1, 0.2 g of modified hydroxyethyl cellulose prepared in Preparation Example 2 was slowly added to 25 ml of deionized water, and stirring was continued until complete dissolution, and 0.8% modified hydroxyethyl cellulose mixture was prepared;

[0082] S2, under stirring, 760 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 2 g of sodium dodecyl sulfate, 4 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin, 35 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenylalanine and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were added in sequence, and stirring was continued for 20 min;

[0083] S3, viscosity and pH were tested by sampling, and 0.8% hydroxyethyl cellulose mixture prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 22 cp, the pH was 7.10, and the surface tension was 31.2 mN / m.

[0084] Example 6

[0085] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0086] S1, 0.3 g of modified hydroxyethyl cellulose prepared in Preparation Example 2 was slowly added to 25 ml of deionized water, and stirring was continued until complete dissolution, and 0.8% modified hydroxyethyl cellulose mixture was prepared;

[0087] S2, under stirring, 800 ml of deionized water, 90 g of glycerol, 30 g of ethylene glycol, 3 g of sodium dodecyl sulfate, 5 g of dodecyl trimethyl ammonium bromide, 0.3 g of acrylic resin, 50 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenylalanine and 1.5 g of 2-butyl-1,2-benzisothiazolin-3-one were added in sequence, and stirring was continued for 20 min;

[0088] S3, viscosity and pH were tested by sampling, and 0.8% hydroxyethyl cellulose mixture prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 26 cp, the pH was 7.30, and the surface tension was 31.5 mN / m.

[0089] Example 7

[0090] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0091] S1, 0.1 g of modified hydroxyethyl cellulose prepared in Preparation Example 3 was slowly added to 12.5 ml of deionized water, and stirring was continued until complete dissolution, and 0.8% modified hydroxyethyl cellulose mixture was prepared;

[0092] S2, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin were added in sequence, after stirring for 30 min, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were added, and stirring was continued for 20 min;

[0093] S3, viscosity and pH were tested by sampling, and 0.8% hydroxyethyl cellulose mixed solution prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 22 cp, the pH was 7.30, and the surface tension was 29.4 mN / m.

[0094] Example 8

[0095] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0096] S1, 0.1 g of modified hydroxyethyl cellulose prepared in Preparation Example 3 was slowly added to 12.5 ml of deionized water, and stirred until completely dissolved to prepare a 0.8% modified hydroxyethyl cellulose mixed solution;

[0097] S2, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin were added in sequence, after stirring for 30 min, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were added, and stirring was continued for 20 min;

[0098] S3, viscosity and pH were tested by sampling, and 0.8% hydroxyethyl cellulose mixed solution prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 22 cp, the pH was 7.30, and the surface tension was 29.4 mN / m.

[0099] Example 9

[0100] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0101] S1, 0.1 g of modified hydroxyethyl cellulose prepared in Preparation Example 3 was slowly added to 12.5 ml of deionized water, and stirred until completely dissolved to prepare a 0.8% modified hydroxyethyl cellulose mixed solution;

[0102] S2, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin are sequentially added, after stirring for 30 min, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one are added, and stirring is continued for 20 min;

[0103] S3, viscosity and pH value are tested by sampling, and 0.8% hydroxyethyl cellulose mixed solution prepared in S1 and 1 g of triethanolamine are used for adjustment, wherein the viscosity is 22 cp, the pH value is 7.20, and the surface tension is 30.1 mN / m.

[0104] Comparative Example 1

[0105] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0106] S1, 0.1 g of hydroxyethyl cellulose is slowly added to 12.5 ml of deionized water, and stirring is performed until complete dissolution, and 0.8% hydroxyethyl cellulose mixed solution is prepared;

[0107] S2, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin are sequentially added, after stirring for 30 min, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one are added, and stirring is continued for 20 min;

[0108] S3, viscosity and pH value are tested by sampling, and 0.8% hydroxyethyl cellulose mixed solution prepared in S1 and 1 g of triethanolamine are used for adjustment, wherein the viscosity is 22 cp, the pH value is 7.20, and the surface tension is 30.1 mN / m.

[0109] Comparative Example 2

[0110] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0111] S1, 0.1 g of hydroxyethyl cellulose is slowly added to 12.5 ml of deionized water, and stirring is performed until complete dissolution, and 0.8% hydroxyethyl cellulose mixed solution is prepared;

[0112] S2, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin were added in sequence, after stirring for 30 min, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were added, and stirring was continued for 20 min;

[0113] S3, viscosity and pH were tested by sampling, and 0.8% hydroxymethyl cellulose mixed solution prepared in S1 and 1 g of triethanolamine were used for adjustment, wherein the viscosity was 20 cp, the pH was 6.90, and the surface tension was 25.3 mN / m.

[0114] Comparative Example 3

[0115] A preparation method of a heat-sensitive aqueous direct liquid ink further comprises the following steps:

[0116] S1, under stirring, 750 ml of deionized water, 75 g of glycerol, 25 g of ethylene glycol, 1 g of sodium dodecyl sulfate, 3 g of dodecyl trimethyl ammonium bromide, 0.2 g of acrylic resin were added in sequence, after stirring for 30 min, 30 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 1 g of 2-butyl-1,2-benzisothiazolin-3-one were added, and stirring was continued for 20 min;

[0117] S3, viscosity and pH were tested by sampling, and 1 g of triethanolamine was used for adjustment, wherein the viscosity was 15 cp, the pH was 6.80, and the surface tension was 21.5 mN / m.

[0118] In order to further verify the performance of the ink prepared in Examples 1-9 and Comparative Examples 1-3, the ink was applied in a direct liquid pen for testing, as follows:

[0119] The pen tube has a diameter of 2.6 mm, and the pen head has a diameter of 0.5 mm.

[0120] 1, drying time

[0121] The ink was drawn on paper at a speed of 5 m / min, and the drying time of the ink was determined by using an eraser.

[0122] 2, storage stability

[0123] The pen core was directly exposed to air at a temperature of 25°C, and after being placed for 1 month, the pen core was tested for writing; the pen core was vertically placed in an oven at 50°C for 3 months, and the number of days without leakage and the leakage prevention property were observed, and the smoothness of the pen core in line drawing was tested on a writing and drawing circle instrument. The test results are shown in Table 1.

[0124]

[0125]

[0126] The present application adds appropriate components and proportions to prepare a heat-sensitive water-based direct liquid ink, improves the storage stability and writing fluency of the ink, and avoids the aggregation and sedimentation of the color paste by controlling the particle size, further improving the writing effect and stability of the ink. The obtained ink has a long storage time and stable anti-bleeding property, and can be used in direct liquid water-based pens. At the same time, due to the good anti-bleeding property, the writing length can be increased by extending the length of the pen shaft, reducing the consumption of pen shaft and pen head materials, and achieving the purpose of energy saving and environmental protection.

[0127] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A heat-sensitive water-based liquid ink, characterized by, It is made from the following raw materials by weight percentage: 75-80% deionized water, 10-20% humectant, 0.02-0.05% filler, 3-7% microencapsulated color paste, 0.1-0.3% preservative, 0.3-0.7% primary dispersant, 0.1-0.5% secondary dispersant, 0.1-0.5% pH adjuster, 0.01-0.05% thickener; The moisturizer is glycerin and ethylene glycol, wherein the mass ratio of glycerin to ethylene glycol is 3:1; The filler is acrylic resin; The main dispersant is an alkylammonium salt; The secondary dispersant is an anionic surfactant; The microcapsule pigment is 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide; The preservative is 2-butyl-1,2-benzisothiazolin-3-one; The pH adjuster is triethanolamine; The thickener is modified hydroxyethyl cellulose, and the preparation method of the modified hydroxyethyl cellulose includes the following steps: S1. Add glacial acetic acid, LiCl and N,N-dimethylacetamide to a container to construct a LiCl / DMAc system, then add hydroxyethyl cellulose and stir until completely dissolved; S2. Add chitosan, acid anhydride and anhydrous sodium acetate, and control the reaction using microwave radiation. S3. After the reaction is complete, terminate the reaction with deionized water and concentrated hydrochloric acid, and shake thoroughly to obtain the reactants; S4. Slowly pour the reactants into an excess of 50-70℃ deionized water and stir to obtain a white flocculent substance; after filtration, wash with deionized water until the pH is greater than 5, put the washing product into an oven to dry, and then grind and pulverize to obtain modified hydroxyethyl cellulose. The acid anhydride is one or more of acetic anhydride, chloroformic anhydride, propionic anhydride, and succinic anhydride.

2. The thermal water-based direct-liquid ink according to claim 1, characterized in that, It is made from the following raw materials by weight percentage: 78.17% deionized water, 16% humectant, 0.02% filler, 5% microencapsulated color paste, 0.1% preservative, 0.5% primary dispersant, 0.1% secondary dispersant, 0.1% pH adjuster, and 0.01% thickener.

3. The thermal water-based direct-liquid ink according to claim 1, characterized in that, The mass ratio of LiCl to N,N-dimethylacetamide in S1 is 1:1.1-1.

3.

4. The thermal water-based direct-liquid ink according to claim 1, characterized in that, In the S2 step, microwave radiation is used to control the temperature at 35-45℃ for a reaction time of 20-60 minutes.

5. A thermal water-based direct-liquid ink according to claim 1, characterized in that, The washing product in step S4 is dried in an oven at 85-90℃ for 3-5 hours.

6. A thermosensitive water-based direct-liquid ink and its preparation method, comprising preparing the thermosensitive water-based direct-liquid ink as described in any one of claims 1-5, characterized in that, It also includes the following steps: S1, Pre-prepared 0.8% modified hydroxyethyl cellulose mixture; S2. Under stirring, add deionized water, glycerol, ethylene glycol, anionic surfactant, alkyl ammonium salt, and acrylic resin in sequence. After stirring for 30 minutes, add 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl peptide and 2-butyl-1,2-benzisothiazolin-3-one, and continue stirring for 20-40 minutes. S3. Sampling and testing viscosity and pH value, respectively adjusted with 0.8% modified hydroxyethyl cellulose mixture and triethanolamine. Viscosity requirements: 20-30 cp, pH value requirements: 7.00-8.30, surface tension: 27-32 mN / m.

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