Painting glue stick capable of being scribbled and preparation method thereof

Abstract

The invention relates to a scribable painting glue stick and a preparation method thereof.The scribable painting glue stick forms a double-soap-base system of sodium stearate and sodium laurate, under the cooperation of polyethylene glycol, the double-soap-base system enables the glue stick to generate the pseudoplastic fluid characteristic, namely, the glue stick is kept in a solid state during standing, and the paint.The scribable painting glue stick has the advantages that the paintable painting glue stick is not prone to cracking; the viscosity of the glue stick is reduced by 60-70% due to shear thinning during smearing, so that the tactile smoothness is improved, acrylic resin serves as a main adhesive, the basic viscosity of the glue stick is guaranteed, meanwhile, the adhesion and the tactile smoothness of the glue stick are ingeniously balanced due to the pseudoplastic fluid characteristics, and the smoothness of a smeared line of the glue stick is effectively improved; the silane coupling agent is adopted to modify the nano color paste, so that the nano color paste and a double-soap-base system form a hydrogen bond network structure, the color adhesion degree is greatly improved, and excellent color fastness is considered on the basis of high color concentration; the hydrogenated castor oil is adopted, so that the film forming efficiency and the storage durability of a painting scene are improved.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, specifically to a writeable drawing glue stick and its preparation method. Background Technology

[0002] Currently, traditional glue sticks primarily function as adhesives, and their composition is mostly based on resin systems such as PVA and PVP. However, they generally suffer from the following drawbacks: (1) Poor leveling: The colloid has insufficient extensibility, resulting in a rough surface after application, making it impossible to achieve smooth drawing lines; (2) Poor color adhesion: Existing glue sticks are difficult to load with high-concentration pigments due to formula limitations, and the pigments are easy to fall off; (3) Long drying time and brittleness after drying: The long curing time of the colloid makes the painting area easy to be contaminated, and the high hardness after curing makes the painting area easy to crack and peel off.

[0003] Therefore, further improvements are needed for the current writable drawing glue sticks. Summary of the Invention

[0004] The first technical problem to be solved by the present invention is to provide a paintable drawing stick that can cleverly balance adhesion and smoothness to improve the smoothness of the applied lines, in light of the current state of the technology.

[0005] The second technical problem to be solved by the present invention is to provide a paintable drawing stick that can improve color density while maintaining excellent color adhesion, in light of the current state of the prior art.

[0006] The third technical problem to be solved by the present invention is to provide a writeable drawing glue stick that can effectively shorten the drying time and thus improve the film-forming efficiency and preservation durability of the painting scene, in view of the current state of the prior art.

[0007] The fourth technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned writable drawing glue stick, in view of the current state of the prior art.

[0008] The technical solution adopted by the present invention to solve at least one of the above-mentioned technical problems is as follows: A type of writable drawing glue stick, comprising the following components by weight percentage: 16%-22% coconut oil; 10%-15% palm oil; 10%-15% hydrogenated castor oil; 6%-10% sodium hydroxide; 4%-7% glycerin; 1%-3% white sugar syrup; 0.1%-0.3% surfactant; 3%-6% polyethylene glycol; 6%-10% acrylic resin; 1%-2% liquid paraffin; 3%-5% stearic acid; 1%-2% lauric acid; 0.3%-0.6% silane coupling agent; 0.1%-0.3% pH buffer; 0.5%-1% talc; 0.1%-0.2% nano-pigment; 0.2%-0.3% preservative; and The remaining water; The paintable drawing glue stick product contains a double soap system of sodium stearate and sodium laurate.

[0009] Preferably, the silane coupling agent is selected from vinylsilane, aminosilane, and methacryloxysilane.

[0010] Preferably, the surfactant is one or two of alkyl glycosides and polyglycerol esters.

[0011] Preferably, the palm oil is selected from 58-degree palm oil, 52-degree palm oil, and 44-degree palm oil.

[0012] Preferably, the pH buffer is selected from triethanolamine, sodium bicarbonate, AMP-95, and sodium citrate.

[0013] Preferably, the preservative is selected from sodium benzoate, phenoxyethanol, and parabens.

[0014] A method for preparing a writeable drawing glue stick includes the following steps: Step S1: According to the above formula for the paintable drawing stick, add coconut oil, palm oil and hydrogenated castor oil to a reaction vessel equipped with a stirring device at room temperature, start the stirring device and heat to 75-80℃ to melt the oil and mix evenly. Step S2: Dissolve NaOH in ice water, and then cool it to below 40°C; Step S3: Slowly pour the NaOH solution obtained in step S2 into the reaction vessel and keep stirring until the mixture reaches a light trace state. The light trace state refers to a consistency similar to thin yogurt. The light trace state is a specific consistency reached by stirring the soap solution during the cold process of making handmade soap. The soap solution can leave a brief trace on the surface of the soap solution, but it will disappear quickly. This term is an existing mature technology and will not be elaborated here. Step S4: Adjust the temperature of the reactor to between 60-70℃, add polyethylene glycol, glycerin and white sugar syrup to the reactor, and stir for 40-60 minutes until completely mixed; the above temperature is controlled between 60-70℃ to prevent yellowing after adding sugar syrup due to excessive temperature, which would affect saponification. Step S5: Keep the system in a water bath at 60-70℃ for 1-2 hours to ensure complete saponification. Step S6: After saponification is complete, raise the temperature of the reactor to 70-80℃ (preferably 75℃), and then add acrylic resin and stir thoroughly. Step S7: Add lauric acid, stearic acid, and liquid paraffin to the reactor. Adjust the temperature to 80-85℃ to melt them. Then add a 30% sodium hydroxide solution and a pH buffer to control the pH of the system between 8.5 and 9.5. Stir for 1-2 hours for secondary saponification, and then keep the temperature at 70-80℃ (preferably 75℃) to control the pH of the system between 8.5 and 9.5 to ensure complete saponification. Step S8: At room temperature, the nano pigment is mixed evenly with a portion of deionized water, then the silane coupling agent and surfactant are added, and the mixture is stirred at 200 rpm for 30 minutes until it is evenly mixed. Step S9: Add the nano-color paste premix obtained in step S8 to the colloidal system kept warm in step S7, and emulsify it at 1000 rpm for 20 min at 70-80℃ (preferably 75℃) until the nano-color paste is dispersed and mixed evenly. Step S10: Add talc to the system and stir to disperse it evenly. Finally, add the preservative and maintain a stirring speed of 50 rpm for vacuum degassing treatment at 55-65℃ for 2-3 hours. The addition of talc makes the glue stick coloring more textured and the coating smoother. During the heat preservation and degassing process, it is necessary to keep the stirring speed slow to prevent the talc from settling due to prolonged standing. Step S11: While the liquid after stirring and degassing is still hot, fill it into containers and cool it to obtain the paintable drawing stick.

[0015] Preferably, the dissolved NaOH solution in step S2 needs to be cooled to below 40°C to prevent the high temperature from affecting the saponification process when added to the reaction vessel.

[0016] Preferably, in step S8, the nano-color paste is modified and pretreated with a silane coupling agent and a surfactant. After surface treatment, the nano-color paste forms a network structure with the soap base through hydrogen bonding. This structure can effectively improve the color adhesion of the pigment, thereby greatly improving the color fastness while maintaining a high color concentration.

[0017] Compared with the prior art, the advantages of the present invention are as follows: This invention forms a dual-soap system of sodium stearate and sodium laurate. With the cooperation of polyethylene glycol, this dual-soap system gives the glue stick pseudoplastic fluid properties, that is, it remains solid when standing, but undergoes shear thinning when applied, reducing the viscosity of the glue stick by 60%-70% to improve the silky smoothness. While using acrylic resin as the main binder to ensure its basic tackiness, the above-mentioned pseudoplastic fluid properties achieve a clever balance between the adhesiveness and the silky smoothness of the glue stick, effectively improving the smoothness of the glue stick application lines. Meanwhile, this invention uses a silane coupling agent to modify the nano-color paste, so that it forms a hydrogen bond network structure with the double soap system, which greatly improves the adhesion of color, thus achieving excellent color fastness while maintaining high color concentration. In addition, this invention uses hydrogenated castor oil, which can work with the dual-soap system to build a three-dimensional network structure inside the colloid, shortening the drying time by 50% after the glue stick is applied. While facilitating bonding, it improves the film-forming efficiency and preservation durability of the painting scene, avoiding the problems of long drying time and brittleness after drying in the prior art. Attached Figure Description

[0018] Figure 1 This is a structural diagram of the product obtained in Embodiment 1 of the present invention; Figure 2 for Figure 1 Coating effect diagram of the corresponding product; Figure 3 This is a coating effect diagram of the product obtained in Comparative Case 2 of the present invention; Figure 4 This is a colloidal state diagram of the product obtained in Comparative Case 2 of the present invention; Figure 5 This is a diagram showing the appearance of the product obtained in Comparative Case 4 of the present invention. Detailed Implementation

[0019] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. 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.

[0020] Implementation Case 1: Based on weight composition, the raw materials of the paintable drawing stick in this embodiment include the following components: 16% coconut oil, 13% palm oil, 13% hydrogenated castor oil, 7% sodium hydroxide, 5% glycerin, 2% white sugar syrup, 0.2% alkyl glycoside, 5% polyethylene glycol, 8% acrylic resin, 2% liquid paraffin, 4% stearic acid, 1.5% lauric acid, 0.5% silane coupling agent, 0.2% pH buffer (where the mass ratio of AMP-95 to triethanolamine is 3:1), 1% talc, 0.2% nano pigment, 0.25% preservative (where the mass ratio of sodium benzoate to parabens is 4:1), and the balance being deionized water. The total of the above components is 100%.

[0021] The method for preparing the paintable drawing glue stick in this implementation case is as follows: Step S1: At room temperature, add coconut oil, palm oil and hydrogenated castor oil to a reaction vessel equipped with a stirring device, start the stirring device and heat to 75-80℃ to melt and mix the oils evenly. Step S2: Dissolve NaOH in ice water, and then cool it to below 40°C; Step S3: Slowly pour the NaOH solution obtained in step S2 into the reaction vessel, and keep stirring until the mixture shows a light trace state; Step S4: Adjust the temperature of the reactor to between 65°C, add polyethylene glycol, glycerin and syrup to the reactor, and stir for 50 minutes until completely mixed; Step S5: Keep the system in a water bath at 60-70℃ for 2 hours to ensure complete saponification. Step S6: After saponification is complete, raise the temperature of the reactor to 75°C, then add acrylic resin and stir thoroughly. Step S7: Add lauric acid, stearic acid, and liquid paraffin to the reactor, adjust the temperature to 82°C to melt them, then add a 30% sodium hydroxide solution and a pH buffer (the mass ratio of AMP-95 to triethanolamine is 3:1) to control the pH of the system between 8.5 and 9.5. Stir for 2 hours to carry out secondary saponification, and then keep warm to 75°C. Step S8: At room temperature, the nano pigment is mixed evenly with a portion of deionized water, then the silane coupling agent and surfactant are added, and the mixture is stirred at 200 rpm for 30 minutes until it is evenly mixed. Step S9: Add the nano-color paste premix obtained in step S8 to the colloidal system kept at temperature in step S7, and emulsify it at 1000 rpm for 20 min at 75°C until the nano-color paste is dispersed and mixed evenly. Step S10: Add talc to the system and stir to disperse it evenly. Finally, add the preservative (sodium benzoate and paraben in a mass ratio of 4:1) and maintain a stirring speed of 50 rpm for vacuum degassing at 60°C for 3 hours. Step S11: While the liquid after stirring and degassing is still hot, fill it into containers and cool it to obtain the finished product of paintable and drawing glue sticks.

[0022] Implementation Case 2: Based on weight composition, the raw materials of the paintable drawing stick in this embodiment include the following components: 22% coconut oil, 10% palm oil, 15% hydrogenated castor oil, 6% sodium hydroxide, 4% glycerin, 3% white sugar syrup, 0.1% polyglycerol ester, 6% polyethylene glycol, 6% acrylic resin, 1% liquid paraffin, 3% stearic acid, 2% lauric acid, 0.6% silane coupling agent, 0.3% pH buffer (where the mass ratio of AMP-95, triethanolamine, and sodium bicarbonate is 1:1:1), 0.5% talc, 0.1% nano pigment, 0.2% preservative (where the mass ratio of sodium benzoate to parabens is 3:1), and the balance being deionized water. The total of the above components is 100%.

[0023] The method for preparing the paintable drawing glue stick in this implementation case is as follows: Step S1: At room temperature, add coconut oil, palm oil and hydrogenated castor oil to a reaction vessel equipped with a stirring device, start the stirring device and heat to 75-80℃ to melt and mix the oils evenly. Step S2: Dissolve NaOH in ice water, and then cool it to below 40°C; Step S3: Slowly pour the NaOH solution obtained in step S2 into the reaction vessel, and keep stirring until the mixture shows a light trace state; Step S4: Adjust the temperature of the reactor to between 65°C, add polyethylene glycol, glycerin and syrup to the reactor, and stir for 50 minutes until completely mixed; Step S5: Keep the system in a water bath at 60-70℃ for 2 hours to ensure complete saponification. Step S6: After saponification is complete, raise the temperature of the reactor to 75°C, then add acrylic resin and stir thoroughly. Step S7: Add lauric acid, stearic acid, and liquid paraffin to the reactor, adjust the temperature to 82°C to melt them, then add a 30% sodium hydroxide solution and a pH buffer (where the mass ratio of AMP-95, triethanolamine, and sodium bicarbonate is 1:1:1) to control the pH of the system between 8.5 and 9.5. Stir for 2 hours to carry out secondary saponification, and then keep warm to 75°C. Step S8: At room temperature, the nano pigment is mixed evenly with a portion of deionized water, then the silane coupling agent and surfactant are added, and the mixture is stirred at 200 rpm for 30 minutes until it is evenly mixed. Step S9: Add the nano-color paste premix obtained in step S8 to the colloidal system kept at temperature in step S7, and emulsify it at 1000 rpm for 20 min at 75°C until the nano-color paste is dispersed and mixed evenly. Step S10: Add talc to the system and stir to disperse it evenly. Finally, add the preservative (sodium benzoate and paraben in a mass ratio of 3:1) and maintain a stirring speed of 50 rpm for vacuum degassing at 60°C for 3 hours. Step S11: While the liquid after stirring and degassing is still hot, fill it into containers and cool it to obtain the finished product of paintable and drawing glue sticks.

[0024] Comparison Case 1: The only difference between this comparative case and implementation case 1 is that stearic acid and lauric acid were not added in this comparative case.

[0025] Comparison Case 2: The only difference between this comparative case and implementation case 1 is that no silane coupling agent was added in this comparative case, that is, the nano pigment was not surface treated with silane coupling agent.

[0026] Comparison Case 3: The only difference between this comparative case and Implementation Case 1 is that hydrogenated castor oil has been replaced with castor oil in this comparative case.

[0027] Comparison Case 4: The only difference between this comparative case and implementation case 1 is that in step S7 of this comparative case, the pH of the system was not controlled between 8.5 and 9.5, but a secondary saponification was carried out directly.

[0028] The performance of the products prepared in Embodiment 1 of the present invention and Comparative Examples 1-4 was tested, and the test results are shown in Table 1 below:

[0029] This invention utilizes safe and environmentally friendly raw materials, meeting the general safety requirements of GB 6675.4-2014 for toys and GB21027-2020 for student supplies. It is safe, non-toxic, and has a wide range of applications. As can be seen from the table above, this invention, by coordinating the selection and proportioning of various substances and controlling the temperature and pH during the preparation process, ultimately yields a glue stick that integrates adhesiveness, applicability, and paintability.

[0030] Specifically, as can be clearly seen from the data in Table 1, this invention effectively achieves a precise balance between the adhesion performance and smooth feel of solid adhesive by specifically introducing a dual-soap base system and synergistically compounding it with acrylic resin and polyethylene glycol. Ultimately, this results in a product exhibiting a delicate crayon-like feel during the coating process, significantly improving the user experience. In terms of color performance optimization, this invention uses silane coupling agent and surfactant to perform composite surface modification treatment on nano color paste, which not only solves the problem of uneven dispersion of traditional color paste, making the overall color distribution of the glue stick uniform, but also significantly improves color concentration and color fastness, which can fully meet the high requirements of color performance in painting, drawing and other scenarios. In terms of colloidal structure and functional enhancement, compared with ordinary castor oil, the hydrogenated castor oil used in this invention is more likely to build a stable three-dimensional network structure inside the colloid due to its molecular structure characteristics. This improvement not only shortens the drying and curing time of the solid glue and ensures the bonding efficiency, but also simultaneously improves the film-forming speed and the preservation durability after film formation in painting scenarios, thus extending the preservation period of the artwork. Furthermore, this invention precisely controls the pH value of the system within the range of 8.5-9.5, which can further enhance the compatibility and stability of each component, ensuring that the performance of key substances such as bis-soap base, resin, and color paste is maximized, and providing an important guarantee for the stable application of the overall function of the glue stick.

[0031] from Figure 1 , 2 As can be seen, the glue stick system obtained in Embodiment 1 of this invention has a uniform and stable color, smooth coating, obvious coloring, and is more aesthetically pleasing and creative. From Figure 3 It can be seen that the coating marks and coloring effect of the glue stick obtained in Comparative Case 2 of this invention are significantly different from those in Implementation Case 1, with lower color concentration and color fastness. From Figure 4 It can be seen that the color uniformity of the glue stick obtained in Comparative Case 2 of this invention is poor. From Figure 5 It can be seen that the glue sticks obtained by the present invention have a lower hardness than those obtained by comparison with Case 4, and there is a problem of coating bending and collapse.

[0032] As can be seen, the technical system of this invention, through multi-dimensional collaboration, achieves a functional breakthrough and value upgrade of traditional glue sticks, transforming them from a single bonding tool into an innovative art tool that combines writing and drawing functions with long-term preservation performance. Furthermore, the product of this invention has passed SGS testing and fully complies with the EN71-3 / 9 EU toy safety standard, providing a safer and higher-quality solution for diverse scenarios such as handicraft creation, decorative bonding, and professional painting.

[0033] The above-described embodiments are merely examples illustrating several implementations of the present invention, and while the descriptions are relatively 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 inventive concept, 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 paintable drawing stick, characterized by: The raw materials used include the following components by weight percentage 16%-22% coconut oil; 10%-15% palm oil; 10%-15% hydrogenated castor oil; 6%-10% sodium hydroxide; 4%-7% glycerol; 1%-3% white sugar syrup; 0.1%-0.3% surfactant; 3%-6% polyethylene glycol; 6%-10% acrylic resin; 1%-2% liquid paraffin; 3%-5% stearic acid; 1%-2% lauric acid; 0.3%-0.6% silane coupling agent; 0.1%-0.3% pH buffer; 0.5%-1% talc; 0.1%-0.2% nano color paste; 0.2%-0.3% preservative; and the balance being water; wherein a double soap base system of sodium stearate and sodium laurate is formed in the finished erasable drawing glue stick.

2. The writable paint stick according to claim 1, wherein: The silane coupling agent is selected from vinyl silane, amino silane, and methacryloyloxy silane.

3. The writable paint stick of claim 2, wherein: The surfactant is one or both of alkyl glycoside and polyglycerol ester.

4. The writable paint stick according to claim 1 or 2 or 3, wherein: The palm oil is selected from 58-degree palm oil, 52-degree palm oil, and 44-degree palm oil.

5. The writable drawing crayon according to claim 1 or 2 or 3, wherein: The pH buffer is selected from triethanolamine, sodium bicarbonate, AMP-95, and sodium citrate.

6. The writable drawing crayon according to claim 1 or 2 or 3, wherein: The preservative is selected from sodium benzoate, phenoxyethanol, and nipagin.

7. A method for preparing a paintable drawing stick, characterized by The method comprises the following steps: Step S1: The formula of the erasable drawing glue stick according to any one of claims 1-6 is added to a reaction kettle equipped with a stirring device under room temperature conditions, the stirring device is started, and the temperature is raised to 75-80°C to melt the oil and fat, and the mixture is stirred until it is uniform; Step S2: The NaOH is dissolved in ice water; Step S3: The NaOH solution prepared in step S2 is slowly poured into the reaction kettle, and stirring is maintained until the mixed solution appears slightly trace; Step S4: The temperature of the reaction kettle is adjusted to between 60-70°C, polyethylene glycol, glycerol, and white sugar syrup are added to the reaction kettle, and stirring is performed for 40-60 min until complete mixing; Step S5: The system is completely saponified by maintaining a 60-70°C water bath for 1-2 hours; Step S6: After saponification is complete, the temperature of the reaction kettle is raised to 70-80°C, and acrylic resin is then added and stirred until it is uniform; Step S7: Lauric acid, stearic acid, and liquid paraffin are added to the reaction kettle, the temperature is adjusted to 80-85°C to melt them, and then sodium hydroxide solution and pH buffer are added to control the pH of the system to between 8.5-9.5, stirring is performed for 1-2 hours for secondary saponification, and then the temperature is maintained at 70-80°C; Step S8: The nano color paste is stirred uniformly with a portion of deionized water at room temperature, and then silane coupling agent and surfactant are added and stirred until the mixture is uniform; Step S9: The nano color paste premix obtained in step S8 is added to the colloidal system maintained in step S7, and high-speed shearing emulsification is performed at 70-80°C until the nano color paste is uniformly dispersed and mixed; Step S10: Talc is added to the system, and stirring is performed until it is uniformly dispersed, and finally a preservative is added, and the system is treated by vacuum degassing at a low stirring speed for 2-3 hours at 55-65°C. Step S11: the liquid after the stirring and defoaming is filled while hot, and the writing and drawing glue stick is prepared after cooling.

8. The method for preparing the writeable drawing glue stick according to claim 7, characterized in that: The NaOH solution after dissolving in step S2 needs to be cooled to below 40℃.

9. The method for preparing the writeable drawing glue stick according to claim 7, characterized in that: The nano color paste in step S8 is modified and pretreated with silane coupling agent and surfactant, and the nano color paste forms a network structure of hydrogen bond combination with the soap base after surface treatment.

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