Smooth wear-resistant gel pen ink and preparation method thereof

Abstract

According to the smooth wear-resistant gel pen ink and the preparation method thereof, a lubricant A is high-molecular polymer particles, spherical nanoparticles can convert sliding between friction surfaces into rolling and reduce the friction coefficient, and meanwhile, the micro-nanoparticles are small in particle size and can be directly filled into large pits in the surface of a ball seat; due to the fact that the ball is an elastic body, in the rolling process of the ball, the ball can be flattened and filled into small pits in the surface of the ball seat, the surface roughness is further reduced, and the friction coefficient is reduced; a phosphate group in the lubricant B or a hydroxyl group in the organic matter can be adsorbed on the surface of the ball seat through chemical or physical action to form a lubricating film, so that direct contact between the ball bead and the ball seat is reduced, mutual friction force is further reduced, and writing smoothness is improved; through interaction of the lubricant A and the lubricant B, flatness of the surface of the ball seat is improved, direct contact between the ball beads and the ball seat is reduced, abrasion between the ball beads and the ball seat is reduced, and therefore writing smoothness is improved.

Description

Technical Field

[0001] This invention relates to the field of water-based gel pen ink, specifically to a smooth and durable gel pen ink and its preparation method. Background Technology

[0002] The ballpoint pen was first developed in 1984 by SAKURA Co., Ltd. of Japan, and named Ballsign. In 1988, Pentel Co., Ltd. of Japan developed a product called Hybrid, thus giving birth to the ballpoint pen. Compared with traditional oil-based and water-based ballpoint pens, ballpoint pens have advantages such as smooth writing, clear handwriting, and water and light resistance, leading to their rapid development and making them one of the mainstream writing tools in my country. With the development of ballpoint pens, the writing feel of the ink has become a key focus for consumers.

[0003] Most ballpoint pens on the market offer a poor writing experience, exhibiting a feeling of resistance and insufficient smoothness. Therefore, to improve writing smoothness, researchers have focused on both the pen tip structure and the ink. The writing smoothness of the pen tip is directly related to the frictional resistance between the ball and the base. The surface roughness of the ball and base affects the consumer's writing experience. However, due to limitations in pen tip manufacturing processes, current technology cannot further improve this aspect from the pen tip structure perspective. Therefore, researchers have focused on the ink. Lubricants are the main raw material affecting ink smoothness. They are mainly adsorbed onto the base surface through physical and chemical methods, reducing the frictional resistance between the ball and base, thereby improving writing smoothness.

[0004] Chinese invention patent ZL202111387148.1 discloses a pigment-based water-based ink and a ballpoint pen containing the ink. This patent comprises a pigment-based colorant, a functional mixture, and an acrylic polymer dispersant with multiple pigment affinity groups. The pigment particles are dispersed and stabilized by the pigment affinity groups on the dispersant's main chain. Simultaneously, the alkoxyphosphate side chains on the dispersant's main chain adsorb onto the surfaces of the ball and the ball base. The dispersed submicron-sized pigment particles separate the friction pair between the ball and the ball base, acting as a micro-bearing, thereby effectively improving lubrication and reducing wear. However, this invention uses a single organic substance adsorbed onto the ball base surface. When the frictional resistance is too high, the adsorbed lubricating film can easily detach, leaving the ball base surface without adsorption. This results in mutual friction between the ball, the ball base, and the pigment particles, thus exacerbating wear on the ball base. Summary of the Invention

[0005] The first technical problem to be solved by the present invention is to provide a smooth and wear-resistant gel pen ink that can improve the flatness of the ball seat surface, reduce the direct contact between the ball and the ball seat, thereby reducing the wear of the ball and the ball seat and improving the writing smoothness, in light of the existing technology.

[0006] The second technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned neutral pen ink, in view of the current state of the prior art.

[0007] The technical solution adopted by the present invention to solve at least one of the above-mentioned technical problems is as follows:

[0008] A smooth, durable gel pen ink, comprising the following components by percentage:

[0009] Deionized water 5%–60%,

[0010] Moisturizer 10%–40%,

[0011] Rust inhibitor 0.01%–5%,

[0012] Lubricant 0.01%–5%,

[0013] pH adjuster 0.01%–5%,

[0014] Thickener 0.01%–5%,

[0015] Preservatives: 0.01%–5%

[0016] Color paste 10%–40%;

[0017] The lubricant is composed of lubricant A and lubricant B, wherein lubricant A is spherical high molecular polymer particles and lubricant B is a higher fatty acid.

[0018] Preferably, the lubricant A is selected from low-density polyethylene resin, polyethylene wax, and polytetrafluoroethylene with a molecular weight of 1-50000; the lubricant B is selected from oleic acid and nonionic surfactants with long-chain alkyl groups.

[0019] Preferably, the lubricant A has a particle size of D90 ≤ 10 μm and a hardness of ≤ 50. More preferably, the lubricant A has a particle size of D90 ≤ 5 μm and a hardness of ≤ 40.

[0020] Preferably, the lubricant B is a monophosphate ester of polyoxyethylene alkyl ether or polyoxyethylene aryl ether, or a diester of polyoxyethylene alkyl ether or polyoxyethylene aryl ether.

[0021] Preferably, the mass ratio of lubricant A to lubricant B is (0.1-10):1, and more preferably (1-10):1.

[0022] Preferably, the humectant is at least one selected from triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, 1,2-propanediol, 1,3-propanediol, glycerin, and polyethylene glycol with a molecular weight of 200-1000.

[0023] Preferably, the rust inhibitor is at least one of dodecenylsuccinic acid and 2-amino-5-mercapto-1-2-3-thiadiazole;

[0024] The preservative is at least one of methylisothiazolinone, chloromethylisothiazolinone, octylisothiazolinone, and dichlorooctylisothiazolinone;

[0025] The pH adjuster is at least one of monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, 2-amino-2-methyl-1-propanol, dimethylethanolamine, N-methylethanolamine, ammonia, sodium hydroxide, and sodium carbonate.

[0026] The thickener is a cellulose-based thickener selected from carboxymethyl cellulose, hydroxyethyl cellulose, sodium carboxymethyl cellulose, hydroxypropyl cellulose, methyl cellulose, and ethyl cellulose; hydrophobically modified acrylic thickeners, such as Dow's TT-615 and TT-935, and BASF's HS1152 and HS1212; alkali-swellable acrylic thickeners, such as BASF's AS1130 and AS1125, and Dow's DR-72; or a natural polymer thickener, such as maltodextrin, xanthan gum, and starch, or a mixture of two or more of these.

[0027] Preferably, the pigment is carbon black with a particle size of D50≤500nm, D90≤1000nm, pH of 7-9, and blackness ≤40. More preferably, it has D50≤250nm, D90≤500nm, pH of 7.5-9, and blackness ≤35, such as LGD2000 from DIC Japan.

[0028] A method for preparing a smooth and abrasion-resistant gel pen ink, using the above-mentioned formula for a smooth and abrasion-resistant gel pen ink, includes the following preparation steps:

[0029] (1) Batching process: Add deionized water, humectant, rust inhibitor and lubricant to the mixing tank and stir at 100-500 r / min for 5-60 min; then add pH adjuster and stir at 100-500 r / min for 5-30 min to adjust the pH to 7-9. Then add thickener, preservative and color paste and stir at 100-500 r / min for 30-90 min. Test the viscosity.

[0030] (2) Viscosity adjustment stage: Turn on the stirrer and set the speed to 100-500 r / min. Add thickener and pH adjuster until the viscosity at 1 rpm is 500-1500 mPa.s and the pH is 7-9. Finally, add water to make up 100% and continue stirring for 5-60 min. After stirring is completed, test the viscosity. If it meets the requirement of viscosity at 1 rpm of 500-1500 mPa.s, discharge and bottle.

[0031] Compared with existing technologies, the advantages of this invention are as follows: During the writing process, the friction generated by the ball and the base determines the smoothness of the pen tip. The lubricant A of this invention is a high-molecular polymer particle. The spherical nanoparticles can transform the sliding between the friction surfaces into rolling, reducing the coefficient of friction. At the same time, the micro-nano particles have a small particle size and can directly fill the larger pits on the base surface. As it is an elastomer, it can be flattened during the ball's rolling process and fill the smaller pits on the base surface, further reducing surface roughness and the coefficient of friction. Meanwhile, the phosphate groups in lubricant B or the hydroxyl groups in organic matter can be adsorbed onto the base surface through chemical or physical action to form a lubricating film, reducing the direct contact between the ball and the base, thereby reducing mutual friction and improving writing smoothness. The interaction between lubricant A and lubricant B improves the flatness of the base surface, reduces the direct contact between the ball and the base, reduces wear on the ball and the base, thereby improving writing smoothness and preventing blank spaces or ink leakage in the writing lines. Detailed Implementation

[0032] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0033] The specifications of the raw materials used in the embodiments of the present invention are as follows:

[0034] Moisturizers: polyethylene glycol (molecular weight 200-1000), purchased from Yoshida Chemical (horse oil); tetraethylene glycol, purchased from Guangzhou Tongjie Chemical Co., Ltd.; triethylene glycol, purchased from Guangzhou Tongjie Chemical Co., Ltd.; 1,3-propanediol, purchased from Guangzhou Tongjie Chemical Co., Ltd.

[0035] Rust inhibitors: dodecenylsuccinic acid, purchased from Shanghai Gaoming Chemical Co., Ltd.; 2-amino-5-mercapto-1-2-3-thiadiazole, purchased from Shanghai Gaoming Chemical Co., Ltd.

[0036] Lubricants: Lubricant A was selected from cetyl polyoxyethylene ether phosphate monoester, purchased from Jiangsu Haian Petrochemical Plant; dodecyl polyoxyethylene ether phosphate monoester, purchased from Jiangsu Haian Petrochemical Plant; dodecyl alcohol ether phosphate, purchased from Jiangsu Haian Petrochemical Plant; Lubricant B was selected from low-density polyethylene resin, purchased from Guangdong Southern BASF Wax Industry Co., Ltd.; polyethylene wax, purchased from Guangdong Southern BASF Wax Industry Co., Ltd.

[0037] pH adjusters: monoethanolamine, purchased from Jiangsu Haian Petrochemical Plant; diethanolamine, purchased from Jiangsu Haian Petrochemical Plant; 2-amino-2-methyl-1-propanol, purchased from Shanghai Kaiyin Chemical Co., Ltd.; ammonia water, purchased from Shanghai Kaiyin Chemical Co., Ltd.

[0038] Thickeners: TT-615, hydrophobic modified acrylic thickener, purchased from Dow Chemical; HS1152, hydrophobic modified acrylic thickener, purchased from BASF; HS1212, hydrophobic modified acrylic thickener, purchased from BASF; maltodextrin, purchased from Weifang Shengtai Pharmaceutical Co., Ltd.; carboxymethyl cellulose, purchased from Weifang Shengtai Pharmaceutical Co., Ltd.

[0039] Preservatives: Methylisothiazolinone, purchased from Shanghai Borui'ao Trading Co., Ltd.; Octylisothiazolinone, purchased from Shanghai Borui'ao Trading Co., Ltd.; Dichlorooctylisothiazolinone, purchased from Shanghai Borui'ao Trading Co., Ltd.

[0040] Pigment paste: LGD 2000, pigment-type pigment paste, DIC (Diocesan International Co., Ltd.)

[0041] Example 1:

[0042] The preparation method of the smooth and abrasion-resistant neutral pen ink in this embodiment includes the following preparation steps:

[0043] (1) Ingredient preparation process: 500g of deionized water, 250g of polyethylene glycol (molecular weight of 200), 10g of dodecenyl succinic acid, 10g of hexadecyl polyoxyethylene ether phosphate monoester, and 10g of low-density polyethylene resin were added to a mixing tank and stirred at 200r / min for 30min; then 10g of monoethanolamine was added and stirred at 200r / min for 5min. The pH value was tested to be 8. Then 10g of TT-615, 10g of methylisothiazolinone and 80g of LGD 2000 were added and stirred at 500r / min for 60min. The viscosity was tested to be 1000mPa.s (1rpm).

[0044] (2) Viscosity adjustment stage: Turn on the stirrer, set the speed to 500r / min, add 10g of TT-615 and 20g of monoethanolamine until the viscosity is 1200mPa.s at 1rpm and the pH is around 8.2. Finally, add water to make up 100% and continue stirring for 60min. After stirring is completed, test the viscosity to be 1100mPa.s (1rpm) and then discharge and bottle.

[0045] Example 2:

[0046] The preparation method of the smooth and abrasion-resistant neutral pen ink in this embodiment includes the following preparation steps:

[0047] (1) Ingredient preparation process: 600g of deionized water, 50g of tetraethylene glycol, 20g of 2-amino-5-mercapto-1-2-3-thiadiazole, 5g of dodecyl polyoxyethylene ether phosphate monoester, and 1g of polyethylene wax were added to a mixing tank and stirred at 100r / min for 5min. Then, 30g of diethanolamine was added and stirred at 100r / min for 5min. After adjusting the pH to 7, 20g of HS1152, 15g of octylisothiazolinone, and 100g of LGD 2000 were added and stirred at 100r / min for 30min. The viscosity was tested to be 810mPa.s (1rpm).

[0048] (2) Viscosity adjustment stage: Turn on the stirrer, set the speed to 100r / min, add 15g of HS1152 and 18g of diethanolamine until the viscosity is 850mPa.s at 1rpm and the pH is around 7. Finally, add water to make up 100% and continue stirring for 30min. After stirring is completed, test the viscosity to be 860mPa.s (1rpm) and then discharge and bottle.

[0049] Example 3:

[0050] The preparation method of the smooth and abrasion-resistant neutral pen ink in this embodiment includes the following preparation steps:

[0051] (1) Ingredient preparation process: 200g of deionized water, 400g of triethylene glycol, 50g of 2-amino-5-mercapto-1-2-3-thiadiazole, 20g of dodecyl ether phosphate, and 3g of low-density polyethylene resin were added to a mixing tank and stirred at 500r / min for 60min; then 30g of 2-amino-2-methyl-1-propanol were added and stirred at 500r / min for 30min. After adjusting the pH to 9, 20g of maltodextrin, 1g of dichlorooctylisothiazolinone, and 210g of LGD 2000 were added and stirred at 500r / min for 90min. The viscosity was tested to be 600mPa.s (1rpm).

[0052] (2) Viscosity adjustment stage: Turn on the stirrer and set the speed to 500 r / min. Add 30 g of maltodextrin and 5 g of 2-amino-2-methyl-1-propanol until the viscosity is 900 mPa.s at 1 rpm and the pH is around 9. Finally, add water to make up the volume to 100% and continue stirring for 30 min. After stirring is completed, test the viscosity at 860 mPa.s (1 rpm) and discharge the material into a bottle.

[0053] Example 4:

[0054] The preparation method of the smooth and abrasion-resistant neutral pen ink in this embodiment includes the following preparation steps:

[0055] (1) Ingredient preparation process: 480g of deionized water, 100g of 1,3-propanediol, 100g of tetraethylene glycol, 10g of dodecenyl succinic acid, 10g of 2-amino-5-mercapto-1-2-3-thiadiazole, 50g of dodecyl polyoxyethylene ether phosphate monoester, and 1g of polyethylene wax were added to a mixing tank and stirred at 300r / min for 10min; then 16g of ammonia water was added and stirred at 200r / min for 15min. After adjusting the pH to 8, 10g of carboxymethyl cellulose, 10g of dichlorooctylisothiazolinone, and 200g of LGD 2000 were added and stirred at 200r / min for 45min. The viscosity was tested to be 1300mPa.s (1rpm).

[0056] (2) Viscosity adjustment stage: Turn on the stirrer, set the speed to 400r / min, add 10g of carboxymethyl cellulose and 17g of ammonia water until the viscosity is 1500mPa.s at 1rpm and the pH is around 8. Finally, add water to make up 100% and continue stirring for 60min. After stirring is completed, test the viscosity at 1500mPa.s (1rpm) and discharge the material into a bottle.

[0057] Example 5:

[0058] The preparation method of the smooth and abrasion-resistant neutral pen ink in this embodiment includes the following preparation steps:

[0059] (1) Ingredient preparation process: 50g of deionized water, 50g of polyethylene glycol (molecular weight 1000), 50g of tetraethylene glycol, 50g of triethylene glycol, 50g of 1,3-propanediol, 10g of dodecenyl succinic acid, 15g of hexadecyl polyoxyethylene ether phosphate monoester, and 5g of polyethylene wax were added to a mixing tank and stirred at 400r / min for 15min; then 10g of monoethanolamine was added and stirred at 200r / min for 25min. After adjusting the pH to 8.5, 8g of TT-615, 7g of HS1152, 1g of methylisothiazolinone and 400g of LGD 2000 were added and stirred at 400r / min for 75min. The viscosity was tested to be 1200mPa.s (1rpm).

[0060] (2) Viscosity adjustment stage: Turn on the stirrer and set the speed to 300r / min. Add 6g of TT-615, 15g of HS1152 and 20g of monoethanolamine until the viscosity is 1000mPa.s at 1rpm and the pH is around 8.5. Finally, add water to make up 100% and continue stirring for 10min. After stirring is completed, test the viscosity to be 990mPa.s (1rpm) and then discharge and bottle.

[0061] Comparative Example 1:

[0062] The preparation method of the smooth and wear-resistant neutral pen ink in this comparative example is as follows: 10g of hexadecyl polyoxyethylene ether phosphate monoester in Example 1 is removed, and deionized water is used to make up to 100%, while other conditions remain unchanged.

[0063] Comparative Example 2:

[0064] The preparation method of the smooth and wear-resistant neutral pen ink in this comparative example is as follows: 10g of low-density polyethylene resin was removed from the 1g of resin in Example 1, and deionized water was used to make up the amount of resin, while other conditions remained unchanged.

[0065] Comparative Example 3:

[0066] The preparation method of the smooth and wear-resistant neutral pen ink in this comparative example is as follows: remove 10g of hexadecyl polyoxyethylene ether phosphate monoester and 10g of low-density polyethylene resin from Example 1, and replenish the amount with deionized water to make up the percentage, while keeping other conditions unchanged.

[0067] The inks obtained from the various embodiments of the present invention and the comparative examples were subjected to functional tests. A bullet-shaped pen tip with a 0.5mm ballpoint diameter was used to make the pen core for relevant tests. The main testing methods involved are as follows:

[0068] (1) Smoothness: The writing lubrication tester was used, in accordance with the GB 37853-2019 standard.

[0069] (2) Wear: Using a microscope, the difference between the data of the exposed ball in the pen tip and the initial data was measured.

[0070] (3) Viscosity: A Bollerfeld E-type viscometer (1 rpm, 25℃) was selected. 1.1 g of the sample to be tested was added to the test dish and the test was carried out at a temperature of 25℃.

[0071] (4) pH: Same as QB T4434-2012 standard.

[0072] The test results are shown in Table 1.

[0073] Table 1

[0074]

[0075]

[0076] Table 1 shows that the interaction between the polymer particles and the long-chain alkyl nonionic surfactant improves the writing smoothness and reduces wear on the pen refill, preventing issues such as ink not flowing out or leaving blank spaces during writing. Specifically:

[0077] Comparing Comparative Example 1 with Example 1, it can be seen that single polymer particles have an improving effect on pen tip wear, but are significantly less effective in improving writing smoothness. Comparing Comparative Example 2 with Example 1, it can be seen that single long-chain alkyl nonionic surfactant has an improving effect on smoothness, but has no effect on wear. Comparing Comparative Example 3 with Example 1, the test results verify that the effects of polymer particles and long-chain alkyl nonionic surfactants on pen tip writing smoothness and wear are relatively important.

[0078] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A smooth and durable gel pen ink, characterized in that: The raw materials used, by percentage, include the following components. Deionized water 5%–60%, Moisturizer 10%–40%, Rust inhibitor 0.01%–5%, Lubricant 0.01%–5%, pH adjuster 0.01%–5%, Thickener 0.01%–5%, Preservatives: 0.01%–5% Color paste 10%–40%; The lubricant is composed of lubricant A and lubricant B, wherein lubricant A is spherical high molecular polymer particles and lubricant B is a higher fatty acid.

2. The smooth and wear-resistant gel pen ink according to claim 1, characterized in that: The lubricant A is selected from low-density polyethylene resin, polyethylene wax, and polytetrafluoroethylene with a molecular weight of 1-50000; the lubricant B is selected from oleic acid and nonionic surfactants with long-chain alkyl groups.

3. The smooth and wear-resistant gel pen ink according to claim 2, characterized in that: The particle size of the lubricant A is D90≤10μm and the hardness is ≤50.

4. The smooth and wear-resistant gel pen ink according to claim 3, characterized in that: The lubricant A has a particle size of D90≤5μm and a hardness of ≤40.

5. The smooth and wear-resistant gel pen ink according to claim 2, characterized in that: The lubricant B is a monophosphate ester of polyoxyethylene alkyl ether or polyoxyethylene aryl ether, or a diester of polyoxyethylene alkyl ether or polyoxyethylene aryl ether.

6. The smooth and wear-resistant gel pen ink according to claim 2, characterized in that: The mass ratio of lubricant A to lubricant B is (0.1~10):

1.

7. The smooth, abrasion-resistant gel pen ink according to any one of claims 1 to 6, characterized in that: The moisturizer is at least one of triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, 1,2-propanediol, 1,3-propanediol, glycerin, and polyethylene glycol with a molecular weight of 200-1000.

8. The smooth, abrasion-resistant gel pen ink according to any one of claims 1 to 6, characterized in that: The rust inhibitor is at least one of dodecenyl succinic acid and 2-amino-5-mercapto-1-2-3-thiadiazole; The preservative is at least one of methylisothiazolinone, chloromethylisothiazolinone, octylisothiazolinone, and dichlorooctylisothiazolinone; The pH adjuster is at least one of monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, 2-amino-2-methyl-1-propanol, dimethylethanolamine, N-methylethanolamine, ammonia, sodium hydroxide, and sodium carbonate. The thickener is a cellulose-based agent, selected from carboxymethyl cellulose, hydroxyethyl cellulose, sodium carboxymethyl cellulose, hydroxypropyl cellulose, methyl cellulose, and ethyl cellulose.

9. The smooth, abrasion-resistant gel pen ink according to any one of claims 1 to 6, characterized in that: The pigment paste is carbon black with a particle size of D50≤500nm, D90≤1000nm, pH of 7-9, and blackness ≤40.

10. A method for preparing a smooth and durable gel pen ink, characterized in that: The formulation of the smooth and abrasion-resistant gel pen ink according to any one of claims 1 to 9 includes the following preparation steps. (1) Batching process: Add deionized water, humectant, rust inhibitor and lubricant to the mixing tank and stir at 100-500 r / min for 5-60 min; then add pH adjuster and stir at 100-500 r / min for 5-30 min to adjust the pH to 7-9. Then add thickener, preservative and color paste and stir at 100-500 r / min for 30-90 min. Test the viscosity. (2) Viscosity adjustment stage: Turn on the stirrer and set the speed to 100-500 r / min. Add thickener and pH adjuster until the viscosity at 1 rpm is 500-1500 mPa.s and the pH is 7-9. Finally, add water to make up 100% and continue stirring for 5-60 min. After stirring is completed, test the viscosity. If it meets the requirement of viscosity at 1 rpm of 500-1500 mPa.s, discharge and bottle.

Images