Food-grade anti-slip silent silica gel coating and preparation method thereof

Abstract

The application discloses a food-grade anti-skid and mute silica gel coating and a preparation method thereof, and belongs to the technical field of food-grade organic silicon materials. The silica gel coating is formed by mixing and curing an A agent and a B agent. The A agent comprises a base polymer, hydrogen-containing silicone oil, MQ silicone resin and low-viscosity silicone oil. The B agent comprises a base polymer, a platinum gold catalyst, a composite tackifier and low-viscosity silicone oil. The base polymer is formed into a gradient system by compounding different-viscosity vinyl silicone oils, and the composite tackifier is composed of a silane coupling agent and triethoxysiloxane. The two-component silica gel material is prepared through vacuum mixing, vacuum degassing and dispensing processes. When used, the two-component silica gel material is mixed in proportion and coated on the surface of a ceramic, glass, stainless steel or plastic substrate, and an anti-skid and mute coating is formed after curing. The coating has excellent anti-skid property, mute property, adhesion and wear resistance, and has good food safety and high and low temperature resistance, and can be widely applied to the surface of tableware, cupware and cup mat food contact products.

Description

Technical Field

[0001] This invention belongs to the technical field of food-grade organosilicon materials, specifically relating to a food-grade anti-slip and sound-absorbing silicone coating and its preparation method. Background Technology

[0002] As people's living standards improve, ceramic cups, glass cups, bowls, plates, coasters, and various food contact utensils are becoming increasingly common in homes, restaurants, and offices. However, these utensils are mostly made of materials such as ceramic, glass, stainless steel, or hard plastic, and their bottom surfaces are usually quite smooth. During use, they are prone to slipping on the table, affecting stability and causing noise when moved or placed, thus reducing the user experience. Furthermore, prolonged friction between the bottom of the utensil and the table can easily scratch the surface, affecting the appearance and lifespan of the furniture.

[0003] To address these issues, existing technologies typically employ methods such as attaching rubber or silicone pads or pre-fabricated anti-slip rings to the bottom of the vessel to increase the coefficient of friction and reduce noise. While these methods can improve anti-slip and noise reduction effects to some extent, they still have many shortcomings. For example, adhesive pads are prone to detachment and curling after long-term use, and their anti-slip and noise-reducing performance significantly decreases as the adhesive layer ages; dirt easily accumulates in the gaps between the pad and the vessel, and these residues are difficult to clean, easily breeding bacteria and resulting in poor hygiene; furthermore, anti-slip accessories often require specialized equipment for molding and secondary coating, leading to high production costs and poor product versatility.

[0004] However, most silicone materials currently available are industrial-grade silicone, which has a high residual content of low-molecular-weight cyclic siloxanes. Some products may also contain heavy metal catalyst residues or other harmful substances, making it difficult to meet the safety requirements for food contact materials. Direct application to the surfaces of tableware, cups, and other products that come into close contact with food poses certain safety risks. Furthermore, existing silicone products generally suffer from uneven dispensing, poor leveling, insufficient adhesion after curing, and a tendency to produce bubbles and pinholes, resulting in unstable anti-slip and durability properties of the coating.

[0005] Therefore, developing a food-grade silicone coating that meets food contact safety standards, possesses excellent anti-slip and noise-reducing properties, strong adhesion, and is wear- and temperature-resistant, along with its preparation method, is of great significance for improving the user experience of utensils and expanding the application fields of food-grade silicone materials. The above-mentioned content is precisely the technical problem that this invention aims to solve. Summary of the Invention

[0006] To overcome the problems of slippery surfaces, noise generation, and scratching of tabletops in existing technologies, as well as the insufficient food safety, poor adhesion, and poor coating durability of existing silicone materials, the present invention aims to provide a food-grade anti-slip and noise-reducing silicone coating and its preparation method. The silicone coating is formed by curing a two-component food-grade addition-cure silicone system. Component A includes a base polymer, hydrogen-containing silicone oil, MQ silicone resin, and low-viscosity silicone oil; Component B includes a base polymer, platinum catalyst, composite tackifier, and low-viscosity silicone oil. Component A and Component B are mixed in a predetermined ratio and applied to the surface of a substrate, then cured to form a food-grade silicone coating with anti-slip, noise-reducing, and wear-resistant properties. The present invention also provides a method for preparing the above-mentioned food-grade anti-slip and noise-reducing silicone coating. By employing a gradient viscosity vinyl silicone oil compound system, an MQ silicone resin reinforcing system, and a composite tackifier system working synergistically, combined with vacuum mixing, vacuum degassing, and grouped storage processes, a two-component food-grade silicone material with excellent workability and performance is obtained. The food-grade anti-slip and noise-reducing silicone coating obtained by this invention has excellent food safety, anti-slip properties, noise reduction, adhesion, and wear resistance. It can be applied to the surface of various utensils and has the advantages of simple application, fast curing, and long service life.

[0007] The objective of this invention can be achieved through the following technical solutions: A food-grade anti-slip and sound-absorbing silicone coating is formed by mixing agent A and agent B in a 1:1 weight ratio and then curing. Agent A, by weight, comprises: 60-75 parts of base polymer; 1.6-2 parts of hydrogen-containing silicone oil; 12-18 parts of MQ silicone resin; and 8-15 parts of low-viscosity silicone oil. Agent B, by weight, comprises: 60-75 parts of base polymer; 0.2-0.3 parts of platinum catalyst; 0.6-0.9 parts of composite tackifier; and 8-15 parts of low-viscosity silicone oil.

[0008] Optionally, the base polymer is vinyl silicone oil, which is compounded from vinyl silicone oils with viscosities of 2000 mPa·s, 5000 mPa·s and 8000 mPa·s in a mass ratio of 6:3:1.

[0009] Optionally, the hydrogen content of the hydrogen-containing silicone oil is 0.18% to 0.22%.

[0010] Optionally, the M / Q ratio of the MQ silicone resin is 0.6 to 0.8, and the vinyl content is 1.5% to 2.5%.

[0011] Optionally, the composite tackifier is composed of a silane coupling agent and a triethoxysiloxane in a mass ratio of 1:1 to 2:1.

[0012] Optionally, the viscosity of the low-viscosity silicone oil is 100–500 mPa·s; the total residual amount of low-molecular-weight cyclic siloxanes in the food-grade anti-slip and sound-absorbing silicone coating is 100–1000 ppm.

[0013] Optionally, a method for preparing a food-grade anti-slip and sound-absorbing silicone coating includes the following steps: S1, add the base polymer, low viscosity silicone oil and MQ silicone resin into the reactor, mix at 50-60°C, and stir at 800-1200 rpm for 40-60 min under a vacuum of -0.095 to -0.098 MPa. After cooling and degassing, agent A is obtained. S2, the base polymer, low viscosity silicone oil and composite tackifier are added to the reactor and mixed at 40-50°C. Then platinum catalyst is added and stirred at 800-1000 rpm for 30-45 min under a vacuum of -0.095 to -0.098 MPa. After cooling, degassing and filtration, agent B is obtained. S3. Fill and store agent A and agent B separately.

[0014] Optionally, the platinum catalyst in step S2 is a Karstedt type platinum catalyst with a platinum content of 3000-5000 ppm; the filtration is performed using a 200-mesh filter.

[0015] Optionally, the viscosities of Agent A and Agent B obtained in steps S1 and S2 are both 8000–15000 mPa·s.

[0016] Optionally, food-grade anti-slip and sound-absorbing silicone coatings are used in the anti-slip and sound-absorbing treatment of ceramic products, glass products, stainless steel products, plastic products, tableware, cups and coasters.

[0017] The beneficial effects of this invention are: This invention employs a base polymer system composed of vinyl silicone oils of varying viscosities, giving the silicone material both excellent flowability and post-curing flexibility. This allows for rapid leveling and uniform film formation during coating, reducing uneven coating thickness, sagging, and cracking, thus improving coating quality. Furthermore, by introducing MQ silicone resin to reinforce the silicone network structure, this invention increases the crosslinking density and structural stability of the coating, resulting in excellent wear resistance and compressive strength. Even under long-term friction and repeated use, the coating maintains its intact structure and stable anti-slip effect. Finally, this invention utilizes a composite tackifying system composed of a silane coupling agent and triethoxysiloxane, which forms a stable bonding interface on substrates such as ceramics, glass, stainless steel, and plastics, significantly improving coating adhesion and effectively preventing peeling, curling, and cracking during use.

[0018] This invention uses hydrogen-containing silicone oil and vinyl silicone oil to form a three-dimensional network structure through addition crosslinking, and combines vacuum mixing and vacuum degassing processes to make the resulting coating structure uniform and dense with a smooth surface. It is not prone to bubbles and pinhole defects, and has excellent anti-slip and noise reduction properties, effectively reducing the noise generated by the sliding and collision of utensils.

[0019] This invention controls the residual content of low-molecular-weight cyclic siloxanes to ensure that the resulting coating meets the safety requirements for food contact materials, while also exhibiting good high and low temperature resistance and water resistance, thus meeting the long-term use needs of food contact products such as tableware and cups. Attached Figure Description

[0020] The invention will now be further described with reference to the accompanying drawings.

[0021] Figure 1 A comparison chart showing the anti-slip performance test results of samples with different formulation ratios. Detailed Implementation

[0022] The present invention will be further described below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. Equivalent adjustments made without departing from the spirit and essence of the present invention should also be considered to fall within the protection scope of the present invention.

[0023] Example 1: The purpose of this example is to verify the feasibility of preparing the food-grade anti-slip and sound-absorbing silicone coating of the present invention when using a lower component ratio.

[0024] (1) Preparation of Agent A: 60 parts of base polymer and 8 parts of low viscosity silicone oil were added to the reactor, heated to 50°C and stirred. Then, 12 parts of MQ silicone resin and 1.6 parts of hydrogen-containing silicone oil were added in batches. The vacuum was drawn to -0.095MPa and stirred at 800rpm for 40min. After cooling to 25°C, the mixture was allowed to stand under vacuum for 20min to remove bubbles, and Agent A was obtained.

[0025] (2) Preparation of Agent B: 60 parts of base polymer and 8 parts of low viscosity silicone oil were added to the reactor and heated to 40°C. Then 0.6 parts of composite thickener were added; 0.2 parts of Karstedt type platinum catalyst were added dropwise and stirred for 15 min; vacuum was drawn to -0.095 MPa and stirred at 800 rpm for 30 min; the temperature was lowered to 25°C and degassed for 20 min. Agent B was obtained after filtration through a 200-mesh filter.

[0026] (3) Coating preparation: Mix agent A and agent B in a 1:1 mass ratio and apply to the bottom surface of ceramic cup or coaster. Cure at 80℃ for 20 minutes and cool naturally to obtain a food-grade non-slip and silent silicone coating.

[0027] Example 2: The purpose of this example is to verify the overall performance of the food-grade anti-slip and sound-absorbing silicone coating of the present invention when using an intermediate ratio.

[0028] (1) Preparation of Agent A: 68 parts of base polymer and 12 parts of low viscosity silicone oil were added to the reactor, heated to 55°C and stirred and mixed. Then, 15 parts of MQ silicone resin and 1.8 parts of hydrogen-containing silicone oil were added in batches. The vacuum was drawn to -0.097MPa and stirred at 1000rpm for 50min. After cooling to 28°C, the mixture was allowed to stand under vacuum for 25min to remove bubbles, and Agent A was obtained.

[0029] (2) Preparation of Agent B: 68 parts of base polymer and 12 parts of low viscosity silicone oil were added to the reactor and heated to 45°C. Then 0.75 parts of composite thickener were added; 0.25 parts of Karstedt type platinum catalyst were added dropwise and stirred for 18 min; vacuum was drawn to -0.097 MPa and stirred at 900 rpm for 40 min; the temperature was lowered to 28°C and degassed for 25 min. Agent B was obtained after filtration through a 200-mesh filter.

[0030] (3) Coating preparation: Mix agent A and agent B in a 1:1 mass ratio and coat the bottom surface of the glass cup. Cure at 80℃ for 20 minutes and cool naturally to obtain a food-grade anti-slip and silent silicone coating.

[0031] Example 3: The purpose of this example is to verify the preparation effect of the food-grade anti-slip and sound-absorbing silicone coating of the present invention when a higher component ratio is used.

[0032] (1) Preparation of Agent A: 75 parts of base polymer and 15 parts of low viscosity silicone oil were added to the reactor, heated to 60°C and stirred. Then, 18 parts of MQ silicone resin and 2 parts of hydrogen-containing silicone oil were added in batches. The vacuum was drawn to -0.098MPa and stirred at 1200rpm for 60min. After cooling to 30°C, the mixture was allowed to stand under vacuum for 30min to remove bubbles, thus obtaining Agent A.

[0033] (2) Preparation of Agent B: 75 parts of base polymer and 15 parts of low viscosity silicone oil were added to the reactor and heated to 50°C. Then 0.9 parts of composite thickener were added; 0.3 parts of Karstedt type platinum catalyst were added dropwise and stirred for 20 min; vacuum was drawn to -0.098 MPa and stirred at 1000 rpm for 45 min; the temperature was lowered to 30°C and degassed for 30 min. Agent B was obtained after filtration through a 200-mesh filter.

[0034] (3) Coating preparation: Mix agent A and agent B at a mass ratio of 1:1 and apply to the bottom surface of stainless steel cup. Curing is carried out at 90℃ for 30 minutes. After natural cooling, a food-grade anti-slip and silent silicone coating is obtained.

[0035] Comparative Example 1: The purpose of this comparative example is to verify the effect of MQ silicone resin on the performance of food-grade anti-slip and noise-reducing silicone coating.

[0036] Except for the absence of MQ silicone resin, the composition of the raw materials and the preparation process are the same as in Example 2. Specifically, Agent A consists of 68 parts of base polymer, 1.8 parts of hydrogen-containing silicone oil, and 12 parts of low-viscosity silicone oil; Agent B consists of 68 parts of base polymer, 0.25 parts of platinum catalyst, 0.75 parts of composite tackifier, and 12 parts of low-viscosity silicone oil. Agents A and B were prepared according to the method of Example 2, mixed in a 1:1 mass ratio, and coated onto the bottom surface of a glass cup. After curing at 80°C for 20 minutes, a non-slip and silent silicone coating was obtained.

[0037] Comparative Example 2: The purpose of this comparative example is to verify the effect of the composite tackifier on the adhesion performance of the food-grade anti-slip and silent silicone coating. Except for the absence of the composite tackifier, the composition of the raw materials and the preparation process were the same as in Example 2. Specifically, Agent A consisted of 68 parts of base polymer, 1.8 parts of hydrogen-containing silicone oil, 15 parts of MQ silicone resin, and 12 parts of low-viscosity silicone oil; Agent B consisted of 68 parts of base polymer, 0.25 parts of platinum catalyst, and 12 parts of low-viscosity silicone oil. Agents A and B were prepared according to the method of Example 2, mixed in a 1:1 mass ratio, and coated onto the bottom surface of a glass cup. The mixture was cured at 80°C for 20 minutes to obtain the anti-slip and silent silicone coating.

[0038] Comparative Example 3: The purpose of this comparative example is to verify the effect of the gradient viscosity vinyl silicone oil compound system on the performance of food-grade anti-slip and noise-reducing silicone coating.

[0039] Except for the use of a single-viscosity vinyl silicone oil instead of a gradient-blended vinyl silicone oil as the base polymer, the composition of the raw materials and the preparation process are the same as in Example 2. Specifically, the base polymer in Agent A is 68 parts of 5000 mPa·s vinyl silicone oil; the base polymer in Agent B is also 68 parts of 5000 mPa·s vinyl silicone oil; the remaining components and amounts of Agents A and B are consistent with those in Example 2. Agents A and B are prepared according to the method of Example 2, mixed at a 1:1 mass ratio, and coated onto the bottom surface of a glass cup. After curing at 80°C for 20 minutes, a non-slip and silent silicone coating is obtained.

[0040] Performance testing: 1. Anti-slip performance test The silicone coating samples prepared in Examples 1-3 and Comparative Examples 1-3 were coated onto the bottoms of glass cups of the same size and left at room temperature for 24 hours. The static friction coefficient between the samples and the wooden tabletop was measured using a friction coefficient tester. Each group of samples was tested 5 times, and the average value was taken as the final test result. The higher the static friction coefficient, the better the anti-slip performance of the coating.

[0041] 2. Adhesion test The silicone coating samples prepared in Examples 1-3 and Comparative Examples 1-3 were coated onto the surface of a glass substrate and allowed to fully cure. Adhesion was tested using the cross-cut adhesion test according to GB / T9286 standard. One hundred squares were drawn on the coating surface using a cross-cutting tool, then standard adhesive tape was applied and quickly peeled off. The extent of coating peeling was observed, and the adhesion grade was determined based on the area of ​​peeling. A higher adhesion grade indicates better bonding performance between the coating and the substrate.

[0042] 3. Wear resistance test The silicone coating samples prepared in Examples 1-3 and Comparative Examples 1-3 were fixed on an abrasion testing machine and subjected to 1000 cycles of reciprocating friction tests under a CS-10 grinding wheel and a load of 500g. After the test, the mass loss rate of the samples was measured, and the wear condition of the coating surface was observed. The lower the mass loss rate, the better the abrasion resistance of the coating.

[0043] 4. Noise Reduction Performance Test The silicone coating samples prepared in Examples 1-3 and Comparative Examples 1-3 were coated onto the bottoms of glass cups of the same size. These cups were then gently placed on a wooden tabletop at the same height. A sound level meter was used to measure the maximum noise level generated at the moment of contact between the cup and the tabletop. Each group of samples was tested five times, and the average value was taken as the final test result. A lower noise level indicates better sound-absorbing and damping performance of the coating.

[0044] Table 1. Performance test results of the examples and comparative examples.

[0045] According to Table 1, the food-grade anti-slip and noise-reducing silicone coatings prepared in Examples 1-3 and Comparative Examples 1-3 showed significant differences in anti-slip performance, adhesion, wear resistance, and noise reduction performance. The overall performance of the Example group was better than that of the Comparative Example group, indicating that the gradient vinyl silicone oil compound system, MQ silicone resin reinforcement system, and composite tackifying system constructed in this invention can effectively improve the comprehensive performance of the coating.

[0046] Based on the anti-slip performance test results Figure 1 The static friction coefficient of Example 2 reached 1.08, the highest among all samples, indicating that it can provide greater contact friction and effectively reduce the slippage of the vessel on the table. Examples 1 and 3 also had high static friction coefficients, while the static friction coefficients of Comparative Examples 1 and 3 decreased significantly, indicating that the MQ silicone resin and gradient viscosity vinyl silicone oil system plays an important role in improving the surface friction performance of the coating.

[0047] The adhesion test results show that both Examples 2 and 3 achieved an adhesion level of 0, indicating a very strong interfacial bonding ability between the coating and the substrate. In contrast, Comparative Example 2, due to the absence of a composite tackifier, experienced an adhesion level of 4, with significant peeling. This demonstrates that the composite tackifier can significantly enhance the bonding strength between the silicone coating and substrates such as glass and ceramics, improving the long-term stability of the coating.

[0048] The wear resistance test results show that Example 2 has a mass loss rate of only 2.6%, significantly lower than other samples, indicating that it has the best wear resistance. Comparative Example 1 showed a mass loss rate that increased to 8.9% after the removal of MQ silicone resin, indicating that MQ silicone resin can effectively improve the crosslinking density and structural stability of the silicone network structure, thereby enhancing the coating's wear resistance and service life.

[0049] Based on the noise reduction performance test results, Example 2 had a maximum noise level of only 49.5 dB, the lowest among all samples, indicating that it has the best cushioning and shock absorption effect. All the example groups significantly reduced the collision noise generated when the vessel came into contact with the table, while the comparative group generally had higher noise levels. This demonstrates that a reasonable formulation design can effectively improve the elasticity and energy absorption capacity of the coating, thereby achieving excellent noise reduction.

[0050] In summary, the present invention significantly improves the anti-slip, adhesion, wear resistance and noise reduction properties of food-grade anti-slip and noise-reducing silicone coatings through the synergistic effect of the gradient vinyl silicone oil compound system, the MQ silicone resin reinforcement system and the composite tackifying system. Among them, Example 2 shows the best comprehensive performance, which fully demonstrates the advanced nature and effectiveness of the technical solution of the present invention.

Claims

1. A food-grade anti-slip and sound-dampening silicone coating, characterized in that, The food-grade anti-slip and sound-absorbing silicone coating is formed by mixing agent A and agent B in a 1:1 weight ratio and then curing. Agent A, by weight, includes: 60-75 parts of base polymer; 1.6-2 parts of hydrogen-containing silicone oil; 12-18 parts of MQ silicone resin; and 8-15 parts of low-viscosity silicone oil. Agent B, by weight, includes: 60-75 parts of base polymer; 0.2-0.3 parts of platinum catalyst; 0.6-0.9 parts of composite tackifier; and 8-15 parts of low-viscosity silicone oil.

2. The food-grade anti-slip and sound-absorbing silicone coating according to claim 1, characterized in that, The base polymer is vinyl silicone oil, which is compounded from vinyl silicone oils with viscosities of 2000 mPa·s, 5000 mPa·s and 8000 mPa·s in a mass ratio of 6:3:

1.

3. The food-grade anti-slip and sound-absorbing silicone coating according to claim 1, characterized in that, The hydrogen content of the hydrogen-containing silicone oil is 0.18% to 0.22%.

4. The food-grade anti-slip and sound-absorbing silicone coating according to claim 1, characterized in that, The MQ silicone resin has an M / Q ratio of 0.6 to 0.8 and a vinyl content of 1.5% to 2.5%.

5. The food-grade anti-slip and sound-absorbing silicone coating according to claim 1, characterized in that, The composite tackifier is composed of a silane coupling agent and a triethoxysiloxane in a mass ratio of 1:1 to 2:

1.

6. The food-grade anti-slip and sound-absorbing silicone coating according to claim 1, characterized in that, The viscosity of the low-viscosity silicone oil is 100-500 mPa·s; the total residual amount of low-molecular-weight cyclic siloxanes in the food-grade anti-slip and sound-absorbing silicone coating is 100-1000 ppm.

7. A method for preparing a food-grade anti-slip and sound-absorbing silicone coating as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1, add the base polymer, low viscosity silicone oil and MQ silicone resin into the reactor, mix at 50-60°C, and stir at 800-1200 rpm for 40-60 min under a vacuum of -0.095 to -0.098 MPa. After cooling and degassing, agent A is obtained. S2, the base polymer, low viscosity silicone oil and composite tackifier are added to the reactor and mixed at 40-50°C. Then platinum catalyst is added and stirred at 800-1000 rpm for 30-45 min under a vacuum of -0.095 to -0.098 MPa. After cooling, degassing and filtration, agent B is obtained. S3. Fill and store agent A and agent B separately.

8. The preparation method according to claim 7, characterized in that, The platinum catalyst mentioned in step S2 is a Karstedt type platinum catalyst with a platinum content of 3000-5000 ppm; the filtration is carried out using a 200-mesh filter.

9. The preparation method according to claim 7, characterized in that, The viscosities of Agent A and Agent B obtained in steps S1 and S2 are both 8000-15000 mPa·s.

10. The application of the food-grade anti-slip and sound-absorbing silicone coating according to any one of claims 1 to 6 in the anti-slip and sound-absorbing treatment of ceramic products, glass products, stainless steel products, plastic products, tableware, cups and coasters.

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