Long-lasting watercolor pen water-based ink and method for preparing the same

Abstract

The application relates to the technical field of ink preparation, and discloses long-acting dry-resistant water-based ink for watercolor pens, which is composed of the following raw materials in parts by mass: water 50-65 parts, polyhydric alcohol 10-35 parts, preservative 0.2-2 parts, and dye 0.1-10 parts. The long-acting dry-resistant water-based ink for watercolor pens significantly inhibits the problems of microbial breeding and dye sedimentation in the moisture evaporation process of the ink in the uncapped state by optimizing the component proportion in the ink formula and the preservative system and utilizing the synergistic effect of the hydrogen peroxide and potassium sorbate composite preservative system. Laboratory verification shows that the uncapped dry-resistant time of the ink is prolonged from 30-60 minutes in the prior art to more than 4 months, and the long-term pain point that the pen tip is dried and blocked due to the user forgetting to cover the pen cap is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of ink preparation technology, and in particular to a long-lasting, dry-resistant water-based watercolor pen ink and its preparation method. Background Technology

[0002] Watercolor pens, as a commonly used tool for children's drawing and office marking, are characterized by their bright colors, ease of use, and rich brushstrokes. They have been widely used in art education, office marking, and handicraft production. Watercolor pen ink is usually a water-based system made by using deionized water as the main solvent, combined with water-soluble dyes or pigments, polyol humectants, and a small amount of additives.

[0003] In existing technologies, to ensure the smooth writing and color saturation of watercolor pens, a certain amount of polyol humectants (such as ethylene glycol, propylene glycol, glycerin, etc.) are usually added to the ink formula. The hygroscopic properties of polyols slow down the evaporation of water from the pen tip, maintaining the flow of ink within the capillary channels of the pen tip. However, this technical solution has the following inherent drawbacks: 1) The ink dries quickly after the cap is removed, and the nib is easily clogged. In existing watercolor inks, the moisturizing effect of polyols largely depends on the ambient humidity. In low humidity environments, the moisture absorption and moisturizing ability of polyols decreases significantly, and the water in the ink continues to evaporate, causing dye or pigment particles to deposit and clump in the gaps between the nib fibers, clogging the capillary channels. Ordinary watercolor inks will stop writing after 30-60 minutes of being left uncapped, and will completely dry and become unusable after more than 2 hours, seriously affecting the user experience. Children often forget to put the cap back on when using watercolor pens, resulting in a large number of watercolor pens being wasted due to the nib drying out, causing a waste of resources.

[0004] 2) Poor water resistance; the ink is prone to smudging when wet. Existing watercolor inks use water as a solvent. When the ink dries and then comes into contact with water or moisture, the dye will dissolve again and spread and smudge, resulting in a blurred picture and color bleeding, which cannot meet the requirements for long-term preservation of paintings.

[0005] 3) Core performance characteristics are mutually restrictive and difficult to balance. To address the above issues, existing improvement technologies typically increase the amount of polyols to enhance moisturizing effects or add water-soluble resins to improve the water resistance of the ink after drying. However, increasing the amount of polyols leads to increased ink viscosity, increased writing resistance, uneven ink flow, and a sticky feeling. While adding water-soluble resins can improve water resistance, the resin film can cause the pen tip fibers to stick together, further accelerating pen tip clogging. More importantly, the effective pore size of the capillary channels decreases after resin film formation, reducing the ink replenishment rate and resulting in thinner writing lines or even ink breaks. Furthermore, resin film on the pen tip surface hinders continuous ink wetting and even spreading, further exacerbating the conflict between writing smoothness and water resistance. Therefore, existing technical solutions cannot fundamentally resolve the core contradiction between long-lasting dryness resistance and writing smoothness / water resistance. Summary of the Invention

[0006] In view of the problems of the above-mentioned existing technical solutions, such as short drying time after cap removal, easy clogging of pen tip, poor water resistance, easy smudging when writing with water, and mutual constraints on core performance, it is difficult to achieve all the requirements at the same time. Therefore, this invention is proposed.

[0007] Therefore, the purpose of this invention is to provide a long-lasting, dry-resistant watercolor pen ink, which aims to achieve long-lasting dry-resistant, excellent water resistance and good writing smoothness, while having a simple preparation process, controllable cost and suitability for large-scale production.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a long-lasting, dry-resistant water-based ink for watercolor pens, comprising the following raw materials in parts by weight: 50-65 parts water, 10-35 parts polyol, 0.2-2 parts preservative, and 0.1-10 parts dye.

[0009] As a preferred embodiment of the long-lasting, dry-resistant watercolor ink of the present invention, the preservative is one or a combination of two of hydrogen peroxide and potassium sorbate; the dye is selected from one or a combination of one or more of brilliant blue, lemon yellow, sunset yellow, eosin Y, acid red 18, acid red 52, and acid red 92.

[0010] As a preferred embodiment of the long-lasting, dry-resistant watercolor ink of the present invention, the polyol is one or more of ethylene glycol, propylene glycol, and glycerin, and the mass fraction of the polyol is 25-35 parts.

[0011] As a preferred embodiment of the present invention, a method for preparing the long-lasting, dry-resistant watercolor ink is characterized by comprising the following steps: Step 1, Solvent preparation: At room temperature, add water to a container and turn on the shear mixer; Step 2: Dissolving the preservative: Add the preservative to the container and stir continuously until the preservative is completely dissolved; Step 3: Adding polyol: Add polyol to the container and stir continuously to ensure that the polyol and water are fully mixed; Step 4: Dye Dissolution and Dispersion: Add the dye to the container and stir at high speed with a shear stirrer to ensure that the dye is fully dissolved and dispersed in the system. Step 5: Homogenization: Keep stirring for at least 40 minutes to ensure that all ingredients are fully mixed and homogeneous, thus obtaining long-lasting, dry-resistant water-based watercolor ink.

[0012] In a preferred embodiment of the present invention, the ambient temperature conditions in steps one to four are 20-30℃; and the rotation speed of the shear mixer is 1000-3000 r / min.

[0013] In a preferred embodiment of the present invention, the stirring time is 3-5 minutes in step two; 3-5 minutes in step three; 5-10 minutes in step four; and 40-90 minutes in step five.

[0014] In a preferred embodiment of the present invention, in step five, the system is stirred until it is uniform and transparent, with no visible insoluble particles or stratification, thus reaching the homogenization endpoint.

[0015] As a preferred embodiment of the present invention, after step five is completed, a step of settling and defoaming is further included: the homogenized ink is settling for 20-40 minutes to allow the air bubbles introduced by stirring to escape naturally.

[0016] As a preferred embodiment of the present invention, after standing and defoaming, the method further includes a filtration step: filtering the ink through a 200-400 mesh filter to remove undissolved large particulate impurities and insoluble matter, and collecting the filtrate to obtain the finished ink.

[0017] As a preferred embodiment of the present invention, the long-lasting, dry-resistant watercolor ink is characterized in that the ink has a drying time of ≥4 months after the cap is removed, and does not smudge or fade when exposed to water after writing.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects: 1. This invention optimizes the component ratios and preservative system in the ink formulation, utilizing the synergistic effect of a composite preservative system of hydrogen peroxide and potassium sorbate to significantly inhibit microbial growth and dye sedimentation during the water evaporation process of ink in the cap-free state. Laboratory verification shows that the cap-free drying time of the ink of this invention is extended from 30-60 minutes in existing technologies to over 4 months, effectively solving the long-standing pain point of users forgetting to cap their pens, leading to dry and clogged nibs.

[0019] 2. The ink of this invention does not smudge or fade when exposed to water after writing and drying, exhibiting excellent color retention. It effectively overcomes the defects of traditional watercolor inks, such as easy smudging and blurring when exposed to water, thus meeting the requirements for long-term preservation of artwork. At the same time, while significantly improving dryness and water resistance, it maintains stable ink viscosity and good fluidity, resulting in smooth writing, even ink flow, and no skimming. It achieves a synergistic unity of long-lasting dryness resistance, excellent water resistance, and smooth writing, solving the technical problem of mutual constraints among the three core performance characteristics in existing technologies.

[0020] 3. The ink of this invention can be prepared simply by mixing the components in proportion and stirring at high speed under normal temperature conditions. No special production equipment is required, the preparation process has low production cost, and it can be directly mass-produced on existing ink production lines, showing good prospects for industrial application. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the steps in preparing the long-lasting, dry-resistant water-based ink for watercolor pens according to the present invention. Detailed Implementation

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] I. Core Formula of Ink This invention provides a long-lasting, dry-resistant water-based watercolor ink, the core of which is as follows: By weight, water 50-65 parts, polyol 10-35 parts, preservative 0.2-2 parts, dye 0.1-10 parts.

[0024] The polyol is one or more of ethylene glycol, propylene glycol, and glycerin, used to adjust the moisturizing properties and viscosity of the ink. Preferably, the polyol has a mass fraction of 25-35 parts.

[0025] The preservative is one or a combination of two of hydrogen peroxide and potassium sorbate, used to inhibit microbial growth in the ink during storage and use, thereby extending the ink's shelf life and decapping resistance time. Preferably, the preservative is present in an amount of 0.5-1.5 parts by weight.

[0026] The dyes are selected from one or more combinations of Brilliant Blue, Lemon Yellow, Sunset Yellow, Eosin Y, Acid Red 18, Acid Red 52, and Acid Red 92, and are selected and compounded according to the desired color. The dyes can be used alone or in combination of two or more.

[0027] II. Ink Preparation Method The method for preparing the ink of the present invention includes the following steps: 1) Solvent preparation: Weigh each raw material according to the formula ratio. Under normal temperature (20-30℃) conditions, add water to the container, turn on the shear mixer, and set the stirring speed to 1000-3000r / min.

[0028] 2) Dissolving the preservative: Add the preservative to the container and stir continuously for 3-5 minutes to completely dissolve the preservative in the water.

[0029] 3) Adding polyols: Add polyols to the container and stir continuously for 3-5 minutes to fully mix the polyols with water and form a uniform mixed solvent system.

[0030] 4) Dye dissolution and dispersion: Add the dye to the container and stir continuously for 5-10 minutes to fully dissolve and disperse the dye in the system, thus initially forming colored ink.

[0031] 5) Homogenization treatment: Keep stirring for 40-90 minutes to ensure that all raw materials are fully mixed and uniform. Stir until the system is uniform and transparent, with no visible insoluble particles or stratification, which is the endpoint of homogenization.

[0032] 6) Let it stand to defoam: Let the homogenized ink stand for 20-40 minutes to allow the air bubbles introduced by stirring to escape naturally.

[0033] 7) Filtration: Filter the ink through a 200-400 mesh filter to remove undissolved large particles and insoluble matter. Collect the filtrate to obtain the finished ink. Example

[0034] Example 1 (Yellow Ink) A long-lasting, dry-resistant water-based watercolor pen ink material, by weight, consists of 65 parts water, 30 parts polyol, 1 part preservative, and 4 parts lemon yellow.

[0035] Preparation method: At room temperature, add water to a container and turn on a shear mixer at 2000 rpm. Add the preservative and stir for 5 minutes until completely dissolved. Add the polyol and stir for 5 minutes. Add lemon yellow and stir for 8 minutes. Continue stirring for 50 minutes until the system is uniform and transparent. Let stand for 30 minutes to defoam. Filter through a 300-mesh filter and collect the filtrate to obtain yellow, long-lasting, dry-resistant watercolor ink.

[0036] Example 2 (Orange Ink) A long-lasting, dry-resistant water-based watercolor pen ink material, by weight, consists of 66 parts water, 30 parts polyol, 1 part preservative, 1 part sunset yellow, and 2 parts eosin Y.

[0037] The same preparation method as in Example 1 was used to obtain orange long-lasting, dry-resistant watercolor ink.

[0038] Example 3 (Orange-red ink) A long-lasting, dry-resistant water-based watercolor ink material, by weight, comprises 61 parts water, 30 parts polyol, 1 part preservative, 3 parts lemon yellow, and 5 parts eosin Y.

[0039] The preparation method is the same as in Example 1, and orange-red long-lasting, dry-resistant water-based watercolor ink is obtained.

[0040] Example 4 (Pink Ink) A long-lasting, dry-resistant water-based ink material for watercolor pens, comprising, by weight, 67 parts water, 30 parts polyol, 1 part preservative, and 2 parts eosin Y.

[0041] The same preparation method as in Example 1 was used to obtain pink, long-lasting, dry-resistant watercolor pen ink.

[0042] Example 5 (Blue Ink) A long-lasting, dry-resistant water-based watercolor pen ink material, by weight, consists of 63 parts water, 30 parts polyol, 1 part preservative, 3 parts brilliant blue, and 3 parts acid red 18.

[0043] The same preparation method as in Example 1 was used to prepare blue, long-lasting, dry-resistant watercolor pen ink.

[0044] Example 6 (Green Ink) A long-lasting, dry-resistant water-based watercolor pen ink material, by weight, comprises 59 parts water, 30 parts polyol, 1 part preservative, 4 parts brilliant blue, 3 parts sunset yellow, and 3 parts acid red.

[0045] The preparation method is the same as in Example 1, and green, long-lasting, dry-resistant water-based watercolor ink is obtained.

[0046] Example 7 (Yellow-green ink) A long-lasting, dry-resistant water-based watercolor pen ink material, by weight, consists of 62 parts water, 30 parts polyol, 1 part preservative, 2 parts brilliant blue, and 5 parts lemon yellow.

[0047] The same preparation method as in Example 1 was used to obtain a yellow-green, long-lasting, dry-resistant watercolor pen ink.

[0048] Example 8 (Dark Red Ink) A long-lasting, dry-resistant water-based watercolor ink material, by weight, comprises 60 parts water, 30 parts polyol, 1 part preservative, 5 parts Acid Red 18, and 4 parts Acid Red 92.

[0049] The same preparation method as in Example 1 was used to obtain a deep red, long-lasting, dry-resistant watercolor pen ink.

[0050] Example 9 (purple-blue ink) A long-lasting, dry-resistant water-based watercolor pen ink material, by weight, consists of 64 parts water, 30 parts polyol, 1 part preservative, 2 parts brilliant blue, and 3 parts acid red 18.

[0051] The same preparation method as in Example 1 was used to obtain a purple-blue long-lasting, dry-resistant watercolor pen ink.

[0052] Example 10 (purple-red ink) A long-lasting, dry-resistant water-based watercolor pen ink material, by weight, consists of 64 parts water, 30 parts polyol, 1 part preservative, 3 parts brilliant blue, and 2 parts eosin Y.

[0053] The same preparation method as in Example 1 was used to obtain a purple-red, long-lasting, dry-resistant watercolor pen ink.

[0054] IV. Comparative Example Comparative Example 1 (Preservative-free control ink) By weight, use 65 parts water, 30 parts polyol, and 4 parts lemon yellow, without adding any preservatives.

[0055] The preparation method is the same as in Example 1.

[0056] Comparative Example 2 (Commercially available ordinary watercolor ink) We selected a commercially available brand of ordinary watercolor pen blue ink as a comparison sample.

[0057] V. Performance Testing and Evaluation (1) Hat-free drying time test Test method: In a constant temperature and humidity chamber, the test environment was set to 23°C and 50% humidity. The watercolor pen sample with the ink of this invention assembled was placed flat in the constant temperature and humidity chamber with the cap removed. The test pen was taken out at regular intervals and written on A4 white paper to observe the ink flow and whether the writing lines were consistent. The results showed that the decapping and drying time of Examples 1-10 of the present invention all reached more than 4 months. After the 4-month test period, the writing effect of the drying-resistant ink in the watercolor pen was consistent with the writing effect before the test, the ink flow remained smooth, the writing lines did not show any breaks, and the writing color remained bright. The addition of preservatives significantly extended the decapping and drying time of the ink. The comparison between Example 1 and Comparative Example 1 showed that the composite preservative system of hydrogen peroxide and potassium sorbate played a key synergistic role.

[0058] (2) Water resistance test Test method: Draw lines on A4 white paper using the inks of Examples 1-10 and Comparative Example 2. After the inks are completely dry, add deionized water to the surface of the lines with a dropper and observe the smudging of the lines. The results show that the water resistance of the ink of this invention is significantly better than that of commercially available ordinary watercolor inks. After writing and drying, it does not smudge or fade when exposed to water, and its color retention is excellent.

[0059] (3) Evaluation of writing fluency Five testers conducted blind tests on Examples 1-10 and Comparative Example 2. The evaluation indicators included: writing smoothness, ink uniformity, presence of white streaks, and presence of ink breaks. The results show that the present invention achieves long-lasting dryness resistance and excellent water resistance while maintaining good writing smoothness, smooth writing, uniform ink output, and no white streaking.

[0060] VI. Results Analysis Based on the above test results, the present invention has the following technical effects: 1) Significantly extended drying time after cap removal. The drying time after cap removal in the embodiments of this invention reaches more than 4 months, while that of commercially available ordinary watercolor inks is only 30-60 minutes, and Comparative Example 1 (without preservatives) is about 45 days. This shows that the present invention, through formula optimization, especially the introduction of the composite preservative system of hydrogen peroxide and potassium sorbate, has produced a significant synergistic effect, effectively inhibiting the problems of dye sedimentation and pen tip clogging during the water evaporation process of ink in the cap-free state.

[0061] 2) Significantly improved water resistance. The ink of this invention does not smudge or fade when exposed to water after writing and drying, overcoming the inherent defect of traditional watercolor inks that are prone to smudging when exposed to water.

[0062] 3) Synergistic unity of core performance. While significantly improving dryness resistance and water resistance, this invention maintains stable ink viscosity, smooth writing, and uniform ink flow, achieving a synergistic unity of long-lasting dryness resistance, excellent water resistance, and smooth writing.

[0063] 4) Color diversity. This invention can prepare inks of various colors by compounding different dyes to meet different usage needs.

[0064] 5) Simple preparation process. The ink of this invention has a simple preparation process, requires no special production equipment, has low production cost, and is suitable for large-scale production.

[0065] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A long-lasting, dry-resistant water-based ink for watercolor pens, characterized in that, It is composed of the following raw materials in parts by weight: 50-65 parts water, 10-35 parts polyol, 0.2-2 parts preservative, and 0.1-10 parts dye.

2. The long-lasting, dry-resistant water-based watercolor ink according to claim 1, characterized in that: The preservative is one or a combination of two of hydrogen peroxide and potassium sorbate; the dye is selected from one or a combination of one of brilliant blue, lemon yellow, sunset yellow, eosin Y, acid red 18, acid red 52, and acid red 92.

3. The long-lasting, dry-resistant water-based ink for watercolor pens according to claim 2, characterized in that: The polyol is one or more of ethylene glycol, propylene glycol, and glycerol, and the mass fraction of the polyol is 25-35 parts.

4. A method for preparing a long-lasting, dry-resistant watercolor pen ink as described in any one of claims 1 to 3, characterized in that, Includes the following steps: Step 1, Solvent preparation: At room temperature, add water to a container and turn on a shear mixer; Step 2: Dissolving the preservative: Add the preservative to the container and stir continuously until the preservative is completely dissolved; Step 3: Adding polyol: Add polyol to the container and stir continuously to ensure that the polyol and water are fully mixed; Step 4: Dye Dissolution and Dispersion: Add the dye to the container and stir at high speed with a shear stirrer to ensure that the dye is fully dissolved and dispersed in the system. Step 5: Homogenization: Keep stirring for at least 40 minutes to ensure that all ingredients are fully mixed and homogeneous, thus obtaining long-lasting, dry-resistant water-based watercolor ink.

5. The method for preparing long-lasting, dry-resistant watercolor ink according to claim 4, characterized in that: The ambient temperature conditions in steps one to four are 20-30℃; the rotation speed of the shear mixer is 1000-3000 r / min.

6. The method for preparing long-lasting, dry-resistant watercolor ink according to claim 5, characterized in that: In step two, the stirring time is 3-5 minutes; in step three, the stirring time is 3-5 minutes; in step four, the stirring time is 5-10 minutes; and in step five, the stirring time is 40-90 minutes.

7. The method for preparing long-lasting, dry-resistant watercolor ink according to claim 6, characterized in that: In step five, the system is stirred until it is uniform and transparent, with no visible insoluble particles or stratification, which marks the end point of homogenization.

8. The method for preparing long-lasting, dry-resistant watercolor ink according to claim 7, characterized in that: After step five is completed, a settling and defoaming step is also included: let the homogenized ink stand for 20-40 minutes to allow the air bubbles introduced by stirring to escape naturally.

9. The method for preparing long-lasting, dry-resistant watercolor ink according to claim 8, characterized in that: After the settling and defoaming process, a filtration step is also included: the ink is filtered through a 200-400 mesh filter to remove undissolved large particles and insoluble matter, and the filtrate is collected to obtain the finished ink.

10. The long-lasting, dry-resistant water-based watercolor ink according to any one of claims 1 to 3, characterized in that: The ink has a drying time of ≥4 months after the cap is removed, and it does not smudge or fade when exposed to water after writing.

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