Preparation method and application of high-strength hydrophobic membrane on inner wall of glass bottle
By forming a silica film on the inner wall of glass bottles using dimethyl silicone oil and volatile organic solvents, the problems of insufficient mechanical strength and easy contamination of the inner wall of glass bottles are solved, achieving efficient and safe hydrophobic treatment, which is suitable for food and drug packaging and large-scale production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-02
- Publication Date
- 2026-04-03
AI Technical Summary
Existing glass bottles lack mechanical strength and are prone to contamination on the inner wall. Current hydrophobic treatment methods have poor adhesion, high cost, and are not suitable for large-scale production.
A stable silica film is formed on the inner wall of a glass bottle by mixing dimethyl silicone oil with a volatile organic solvent and heat treatment. This film penetrates microcracks and imparts hydrophobicity. Temperature and viscosity control are combined to ensure chemical bonding.
It significantly improves the mechanical strength of glass bottles, achieves long-lasting hydrophobicity and stain resistance, is suitable for food and pharmaceutical packaging, and is suitable for large-scale industrial production.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of glass product surface treatment technology, specifically relating to a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle and its application. Background Technology
[0002] Glass is a widely used amorphous inorganic non-metallic material, generally made from a variety of inorganic minerals as the main raw materials, with the addition of a small amount of auxiliary materials. Glass is also used in the manufacture of glass bottles. Glass bottles are packaging containers for food, beverages and many other products, and are widely used. They have advantages such as good chemical stability, high barrier properties, and good transparency. They can be reused multiple times, are heat-resistant, pressure-resistant, and easy to clean. They can be sterilized at high temperatures or stored at low temperatures. However, glass bottles have two inherent defects: (1) Insufficient mechanical strength: During production and transportation, micron- or submicron-sized microcracks are easily generated on the surface and inner wall of the glass bottle. These microcracks become stress concentration points and are easily expanded under external force, resulting in the mechanical strength of the glass bottle (such as internal pressure resistance and impact resistance) being far lower than its theoretical value. (2) Hydrophilic surface that is easily contaminated: The surface of glass is rich in silanol groups, which are hydrophilic and have high surface energy. When containing viscous liquids (such as syrups, honey, lotions, and protein-based medications), the contents easily wet and adhere to the bottle walls, causing residue buildup, leading to waste, inaccurate dosage, and difficulty in cleaning. Current technologies cannot simultaneously and effectively solve both the problems of insufficient strength and easy contamination of the inner walls of glass bottles. Existing hydrophobication treatments for glass bottles result in weak adhesion between the formed film and the glass substrate, typically relying on physical adsorption, leading to poor durability and easy failure under friction or immersion in contents. Furthermore, some hydrophobication treatment methods use chemical reagents that may pose biosafety risks and are unsuitable for food and pharmaceutical packaging. Existing hydrophobication treatment methods are complex and costly, making them unsuitable for rapid, large-scale industrial production of glass bottles. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle and its application. The method for preparing the high-strength hydrophobic film on the inner wall of a glass bottle is simple in process, has significant effect, and can simultaneously enhance the mechanical strength of the glass bottle and give its inner wall durable strong hydrophobicity and stain resistance.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle, comprising the following steps: S1. Mix dimethyl silicone oil with a volatile organic solvent and stir until dissolved to obtain a coating solution; S2. Coat the inner wall of the glass bottle with the coating solution; S3. Cure and cool the coated glass bottle.
[0005] Through extensive experiments, the inventors of this application discovered that coating the inner wall of a glass bottle with a solution obtained by mixing dimethyl silicone oil with a volatile organic solvent and then heat-curing it forms a stable "siloxane film." This film can penetrate and anchor in the microcracks of the glass inner wall, effectively preventing crack propagation and thus significantly improving mechanical strength. At the same time, the stable methyl groups on the film surface face inward, giving the inner wall a durable and strong hydrophobic and antifouling ability.
[0006] In a preferred embodiment of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle according to the present invention, the viscosity of the dimethyl silicone oil is 40-60 cs. The present invention uses dimethyl silicone oil with a viscosity of 40-60 cs, which provides suitable fluidity, allowing it to effectively penetrate into microcracks while ensuring both coating effectiveness and safety.
[0007] In a preferred embodiment of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle according to the present invention, the volatile organic solvent includes at least one of ethyl acetate, acetone, n-hexane, or isopropanol.
[0008] More preferably, the volatile organic solvent is food-grade ethyl acetate.
[0009] In a preferred embodiment of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle according to the present invention, the volume ratio of dimethyl silicone oil to volatile organic solvent is dimethyl silicone oil: volatile organic solvent = 2: 50-150. The inventors of this application have discovered that the volume ratio of dimethyl silicone oil to volatile organic solvent ensures film uniformity and suitable thickness.
[0010] In a preferred embodiment of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle according to the present invention, the curing temperature in step S3 is 300℃-400℃. Research has found that the heat treatment temperature range is crucial for forming strong Si-O-Si covalent bonds and stabilizing the "siloxane film." Too low a temperature results in insufficient cross-linking and poor adhesion, while too high a temperature causes the organic groups to decompose, leading to loss of hydrophobic properties. When the curing temperature is 300℃-400℃, the formed silica film is chemically bonded to the glass substrate, exhibiting extremely strong adhesion, making it difficult to detach, and its durability is far superior to physically adsorbed coatings.
[0011] In a preferred embodiment of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle according to the present invention, the curing time in step S3 is 10-30 min.
[0012] As a preferred embodiment of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle according to the present invention, the coating method in step S2 includes spraying, brushing or dipping.
[0013] In a preferred embodiment of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle according to the present invention, the cooling in step S3 is cooling to room temperature.
[0014] The present invention also provides the application of the method for preparing the high-strength hydrophobic film on the inner wall of the glass bottle in the preparation of glass bottles.
[0015] The present invention also provides a glass bottle prepared by the method described above for preparing a high-strength hydrophobic film on the inner wall of the glass bottle.
[0016] The beneficial effects of this invention are as follows: This invention provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. By heat-treating dimethyl silicone oil within a specific viscosity range at a specific temperature, this invention achieves a synergistic effect of simultaneously repairing microcracks and constructing a strong hydrophobic film on the inner wall of the glass bottle, thus solving the two major problems of strength and stain resistance in glass bottles. The core reagents (dimethyl silicone oil and food-grade ethyl acetate) used in the preparation method of the high-strength hydrophobic film on the inner wall of the glass bottle are physiologically inert and form a stable silica film after high-temperature curing. This film is safe and non-toxic, suitable for food and pharmaceutical packaging. The preparation method of the high-strength hydrophobic film on the inner wall of the glass bottle uses high-speed automatic atomization spraying, combined with a drying oven, enabling online, continuous, and automated production of glass bottles with high efficiency and controllable costs. Detailed Implementation
[0017] To more concisely and clearly demonstrate the technical solution, purpose, and advantages of the present invention, the technical solution of the present invention is described in detail below with reference to specific embodiments. Unless otherwise specified, the reagents involved in the embodiments of the present invention are all commercially available products and can be purchased through commercial channels.
[0018] Example 1 This embodiment provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle, including the following steps: S1. Accurately weigh 2.0 ml of Dow Corning PMX-200 silicone oil (viscosity 50 cs), and then measure 100.0 ml of food-grade ethyl acetate conforming to GB 1886.190-2016 standard. Slowly add the silicone oil to the ethyl acetate while stirring with a magnetic stirrer at 500 rpm for 5 minutes until a completely homogeneous and transparent solution is obtained; S2. Transfer the above solution to the storage tank of the automatic spraying equipment. The equipment is equipped with a high-speed atomizing nozzle suitable for compressed air, and the compressed air is set to 0.5MPa. When the glass bottle (100 700mL food packaging soda-lime glass bottles, cleaned with deionized water and thoroughly dried in a 120℃ oven) enters the neck spraying position, the photoelectric detection track is aligned with the nozzle, and the high-speed solenoid valve is opened to spray for 0.2s to spray the mouth and neck. After the glass bottle continues to enter the bottom spraying position, the high-speed solenoid valve is opened to spray for 0.2s to spray the body and bottom of the bottle. After two sprayings, ensure that the inner wall of the bottle is uniformly and comprehensively sprayed. S3. After spraying, the glass bottles are immediately sent into a tunnel drying oven via a conveyor belt. The temperature inside the oven is kept constant at 320℃, and the glass bottles stay in the oven for 20 minutes. After drying, the glass bottles are removed from the drying oven via a conveyor belt and allowed to cool naturally at room temperature.
[0019] Example 2 This embodiment provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Embodiment 1, except that the silicone oil used in step S1 is different. The silicone oil used in this embodiment is Dow Corning PMX-200 silicone oil (viscosity 20cs).
[0020] Example 3 This embodiment provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Embodiment 1, except for step S1. In this embodiment, step S1 specifically involves: accurately weighing 2.0 ml of Dow Corning PMX-200 silicone oil (viscosity 50 cs) and measuring 100.0 ml of acetone. The silicone oil is slowly added to the acetone while simultaneously stirring with a magnetic stirrer at 500 rpm for 5 minutes until a completely homogeneous and transparent solution is obtained.
[0021] Example 4 This embodiment provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle, including the following steps: S1. Accurately weigh 2.0 ml of Dow Corning PMX-200 silicone oil (viscosity 50 cs), and then measure 70.0 ml of food-grade ethyl acetate conforming to GB1886.190-2016 standard. Slowly add the silicone oil to the ethyl acetate while stirring with a magnetic stirrer at 500 rpm for 5 minutes until a completely homogeneous and transparent solution is obtained; S2. Transfer the above solution to the storage tank of the automatic spraying equipment. The equipment is equipped with a high-speed atomizing nozzle suitable for compressed air, and the compressed air is set to 0.5MPa. When the glass bottle (100 700mL food packaging soda-lime glass bottles, cleaned with deionized water and thoroughly dried in a 120℃ oven) enters the neck spraying position, the photoelectric detection track is aligned with the nozzle, and the high-speed solenoid valve is opened to spray for 0.2s to spray the mouth and neck. After the glass bottle continues to enter the bottom spraying position, the high-speed solenoid valve is opened to spray for 0.2s to spray the body and bottom of the bottle. After two sprayings, ensure that the inner wall of the bottle is uniformly and comprehensively sprayed. S3. After spraying, the glass bottles are immediately sent into a tunnel drying oven via a conveyor belt. The temperature inside the oven is kept constant at 320℃, and the glass bottles stay in the oven for 20 minutes. After drying, the glass bottles are removed from the drying oven via a conveyor belt and allowed to cool naturally at room temperature.
[0022] Example 5 This embodiment provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Embodiment 1, except for step S1. In this embodiment, step S1 specifically involves: accurately weighing 2.0 ml of Dow Corning PMX-200 silicone oil (viscosity 50 cs) and measuring 50.0 ml of acetone. The silicone oil is slowly added to the acetone while simultaneously stirring with a magnetic stirrer at 500 rpm for 5 minutes until a completely homogeneous and transparent solution is obtained.
[0023] Example 6 This embodiment provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Embodiment 1, except for step S1. In this embodiment, step S1 specifically involves: accurately weighing 2.0 ml of Dow Corning PMX-200 silicone oil (viscosity 50 cs) and measuring 150.0 ml of acetone. The silicone oil is slowly added to the acetone while simultaneously stirring with a magnetic stirrer at 500 rpm for 5 minutes until a completely homogeneous and transparent solution is obtained.
[0024] Example 7 This embodiment provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Embodiment 1, except for step S3. In this embodiment, step S3 is as follows: the coated glass bottle is immediately fed into a tunnel drying oven via a conveyor belt. The temperature inside the oven is kept constant at 250°C, and the glass bottle stays in the oven for 20 minutes. After drying, the glass bottle is removed from the drying oven via a conveyor belt and allowed to cool naturally at room temperature.
[0025] Comparative Example 1 This comparative example provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Example 1, except for step S1. In this example, step S1 specifically involves: accurately weighing 2.0 ml of monobutyltin trichloride and measuring 100.0 ml of ethanol. The monobutyltin trichloride solution is slowly added to the ethanol while simultaneously stirring with a magnetic stirrer at 500 rpm for 5 minutes until a completely homogeneous and transparent solution is obtained.
[0026] Comparative Example 2 This comparative example provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Example 1, except for step S3. Specifically, step S3 in this comparative example is as follows: the coated glass bottle is immediately fed into a tunnel drying oven via a conveyor belt. The temperature inside the oven is kept constant at 200°C, and the glass bottle stays in the oven for 20 minutes. After drying, the glass bottle is removed from the drying oven via a conveyor belt and allowed to cool naturally at room temperature.
[0027] Comparative Example 3 This comparative example provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Example 1, except for step S3. Specifically, step S3 in this comparative example is as follows: the coated glass bottle is immediately fed into a tunnel drying oven via a conveyor belt. The temperature inside the oven is kept constant at 500°C, and the glass bottle stays in the oven for 20 minutes. After drying, the glass bottle is removed from the drying oven via a conveyor belt and allowed to cool naturally at room temperature.
[0028] Comparative Example 4 This comparative example provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Example 1, except that the silicone oil used in step S1 is different. The silicone oil used in this comparative example is Dow Corning PMX-200 silicone oil (viscosity 10cs).
[0029] Comparative Example 5 This comparative example provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Example 1, except that the silicone oil used in step S1 is different. The silicone oil used in this comparative example is Dow Corning PMX-200 silicone oil (viscosity 100cs).
[0030] Comparative Example 6 This comparative example provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Example 1, except that the amount of ethyl acetate used in step S1 is 30.0 ml.
[0031] Comparative Example 7 This comparative example provides a method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle. The specific steps are the same as in Example 1, except that the amount of ethyl acetate used in step S1 is 200.0 ml.
[0032] Example of effect This example demonstrates the effectiveness of testing the glass bottles prepared in Examples 1-7 and Comparative Examples 1-7: Strength test: Ten glass bottles treated according to each example and comparative example and ten untreated blank bottles were randomly selected for hydraulic burst test. The test method is GB / T 4546-2008 Test method for internal pressure resistance of glass containers.
[0033] Hydrophobicity test: The inner walls of the glass bottles after treatment in each embodiment and comparative example were tested using a contact angle meter. Each sample was tested three times and the average value was taken.
[0034] Anti-fouling test: Inject equal amounts of simulated 30% concentration syrup (a high-viscosity solution containing pigments) into glass bottles of the treatment group and the blank group, then pour them out completely, invert them and let them stand for 300 seconds, visually observe and weigh the residual amount.
[0035] The results are shown in Table 1.
[0036] Table 1 As shown in Table 1, the glass bottles treated with the high-strength hydrophobic film preparation method of Examples 1-7 exhibit significantly improved burst strength and hydrophobic properties, with a maximum increase of 24% in burst pressure and a water contact angle of over 115° on the inner wall, demonstrating strong hydrophobicity. They also show good stain resistance, with residue reduction reaching up to 79%. Comparing Example 1 with Comparative Example 1, the use of non-silicone oil-based materials for coating improves the strength of the glass bottle to some extent, indicating a certain ability to repair cracks. However, the water contact angle is only 65°, indicating moderate hydrophobicity, and the film layer is unstable with poor stain resistance. Comparing Example 1 with Comparative Examples 2 and 3, the heat treatment temperature significantly affects the crosslinking, curing, and chemical bonding of silicone oil to the glass surface, forming a strong silica film. At lower temperatures (Comparative Example 2), the burst pressure only increases by 5%, showing a weak strengthening effect; the water contact angle is 85°, and drops below 60° after wiping with a cotton swab, indicating that the film layer is physically adsorbed, poorly bonded, and has poor durability. When the temperature is too high (Comparative Example 3), the burst pressure increases by 20%, and the strengthening effect is acceptable, but the water contact angle is only 50°, and the hydrophobic properties are lost. This is because the high temperature causes the methyl groups (-CH3) in the silicone oil to be oxidized and decomposed, destroying the low surface energy structure. Comparing Example 1 with Comparative Examples 4 and 5, it can be seen that the viscosity of dimethyl silicone oil has a significant impact on the formation of a stable silica film and the penetration and repair of microcracks. When the viscosity is not within the range of 40-60 cs, the formed film is uneven, and the improvement in the strength and hydrophobicity of the glass bottle is poor. Comparing Example 1 with Comparative Examples 6 and 7, it can be seen that the volume ratio of dimethyl silicone oil to volatile organic solvent affects the film uniformity and thickness. When the ratio is too low, the film layer is too thick, and after drying, it turns white in some areas. The water contact angle is good, but the appearance is unacceptable. When the ratio is too high, the burst pressure only increases by 8%.
[0037] Finally, 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 the scope of protection of the present invention. 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 essence and scope of the technical solutions of the present invention.
Claims
1. A method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle, characterized in that, Includes the following steps: S1. Mix dimethyl silicone oil with a volatile organic solvent and stir until dissolved to obtain a coating solution; S2. Coat the inner wall of the glass bottle with the coating solution; S3. Cure and cool the coated glass bottle.
2. The method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to claim 1, characterized in that, The viscosity of the dimethyl silicone oil is 40-60 cs.
3. The method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to claim 1, characterized in that, The volatile organic solvent includes at least one of ethyl acetate, acetone, n-hexane, or isopropanol.
4. The method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to claim 1, characterized in that, The volume ratio of the dimethyl silicone oil to the volatile organic solvent is dimethyl silicone oil: volatile organic solvent = 2: 50-150.
5. The method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to claim 1, characterized in that, The curing temperature in step S3 is 300℃-400℃.
6. The method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to claim 1, characterized in that, The curing time in step S3 is 10-30 minutes.
7. The method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to claim 1, characterized in that, The coating method in step S2 includes spraying, brushing, or dipping.
8. The method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to claim 1, characterized in that, The cooling in step S3 is cooling to room temperature.
9. The application of the method for preparing the high-strength hydrophobic film on the inner wall of a glass bottle according to any one of claims 1-8 in the preparation of glass bottles.
10. A glass bottle prepared by the method for preparing a high-strength hydrophobic film on the inner wall of a glass bottle according to any one of claims 1-8.