Breathable light silica gel chest pad and preparation method thereof

Abstract

The invention relates to the technical field of bras, and particularly discloses a breathable light silica gel breast pad and a preparation method thereof.The silica gel breast pad is prepared from a component A and a component B. The component A is prepared from, by weight, 16-24 parts of vinyl silicone oil, 8-16 parts of dimethyl silicone oil, 32-44 parts of white carbon black, 32-46 parts of MQ silicon resin, 0.01-0.02 part of catalyst and 1-3 parts of foaming agent; the component B comprises 55-65 parts of modified vinyl silicone oil, 35-45 parts of hydroxyl silicone oil and 32-44 parts of an inhibitor, the vinyl MQ silicone resin and the platinum catalyst take effect synergistically, and the reinforcing effect is effectively achieved; meanwhile, through the modified vinyl silicone oil, the elasticity of the silica gel is enhanced by means of the improvement of the flexibility of a chain, the silica gel chest pad which is light in weight, good in elasticity, high in breathability and safe is obtained, the production process is non-toxic and harmless, harmful substances are not generated, and good experience is provided for consumers.

Description

Technical Field

[0001] The invention belongs to the technical field of bras, and particularly relates to a breathable and lightweight silicone breast pad and a preparation method thereof. Background Art

[0002] Bra pads are an important part of underwear, and their design and materials have undergone a transformation from single to diversified. Bra pads on the market are mainly divided into silicone pads and sponge pads. Sponge products have the defects of yellowing easily and not easy to dry after washing, so consumers are increasingly inclined to choose silicone pads that are both comfortable and convenient. In the current market, with the increase in women's demand for underwear comfort and personalization, the design and function of bra pads are also constantly innovating. Various functional bra pads have appeared on the market, such as anti-exposure, invisible, gathering, health care, etc., to meet different occasions and needs.

[0003] At present, the technical improvements on breast pads are mainly focused on integrating added values ​​such as medical care. For example, patent CN105394826B obtains a Chinese medicine health-care silicone breast pad by injecting Chinese medicine powder into the inner film bag. Another example is patent CN107467726B which provides a multifunctional composite breast pad containing a drug layer and a drug-dissolving volatile layer. The heat generated by the solid-liquid phase change volatilizes the water-soluble and fat-soluble drug components to play a health-care role.

[0004] Although the above-mentioned breast pads with health care functions have a certain market share, the products are too niche. The function of the mainstream silicone breast pads on the market is still mainly support, and the feeling of use is relatively stuffy. Therefore, there is an urgent need for a breathable, lightweight and elastic silicone breast pad on the market. Summary of the invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the present invention uses vinyl MQ silicone resin and platinum catalysts to work synergistically to effectively play a reinforcing role. At the same time, through modified vinyl silicone oil, the elasticity of silicone is enhanced by improving the flexibility of the chain, thereby obtaining a lightweight, elastic, highly breathable and safe silicone breast pad. The production process is non-toxic, harmless and does not produce harmful substances, providing consumers with a good experience.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] On the one hand, the present invention provides a breathable and lightweight silicone breast pad. The raw materials include component A and component B in a mass ratio of 1: (6-9). In parts by weight, the component B includes 55-65 parts of modified vinyl silicone oil, 35-45 parts of hydroxy silicone oil and 32-44 parts of inhibitor; the component A includes 16-24 parts of vinyl silicone oil, 8-16 parts of dimethyl silicone oil, 32-44 parts of white carbon black, 32-46 parts of MQ silicone resin, 0.01-0.02 parts of catalyst and 1-3 parts of foaming agent.

[0008] In some embodiments, the elastic elongation of the breathable lightweight silicone breast pad is ≥380%, and the oxygen permeability T0 is ≥300cm 3 / m 2 ·24h·0.1MPa.

[0009] In some embodiments, the catalyst is any one of a platinum catalyst, an amine catalyst and an organotin catalyst.

[0010] Preferably, the catalyst is a platinum catalyst.

[0011] More preferably, the platinum catalyst is a Karstedt catalyst.

[0012] The final product of the silicone rubber produced by the present invention is a chest pad, which is in direct contact with the human body, so the selection of the catalyst is very strict. The present invention preferably uses the Karstedt catalyst among the platinum catalysts, whose main component is a zero-valent platinum-vinylsiloxane complex, which has high reactivity, is non-toxic, harmless, and does not produce harmful substances during the production process. In particular, in liquid silicone rubber, its high activity and high selectivity can quickly catalyze the cross-linking reaction of silicone rubber at a relatively low temperature without producing side reactions and harmful gases.

[0013] In some embodiments, the particle size of the white carbon black is 5 to 50 nm.

[0014] In some embodiments, the MQ silicone resin is one or more of methyl MQ silicone resin, vinyl MQ silicone resin or phenyl MQ silicone resin.

[0015] Preferably, the MQ silicone resin is vinyl MQ silicone resin.

[0016] The present invention specifically selects the vinyl MQ silicone resin, which can react with the SiH cross-linking agent under the action of a platinum catalyst to undergo a silylation reaction and chemically bond with the raw rubber, thereby forming a three-dimensional network structure to play a reinforcing role, while not causing the viscosity of the system to increase too quickly, which is beneficial to subsequent operations.

[0017] In some embodiments, the preparation steps of the modified vinyl silicone oil are as follows:

[0018] Under nitrogen protection, 1,4-bis(dimethylhydroxysilyl)benzene, 4,4'-bis(dimethylhydroxysilyl)diphenyl ether, cyclotetrasiloxane mixture and vinyl double cap are stirred at 90-120° C. for 20-40 min, then tetramethylammonium hydroxide is added, and after stirring for 0.5-1 h, vacuum is evacuated, and the mixture is kept warm for 1-2 h. The mixture is then heated to 150-160° C. and kept warm for 0.5-1 h, and then heated to 170-180° C. and kept warm for 1-2 h, and then cooled to room temperature to obtain the modified vinyl silicone oil.

[0019] Preferably, the viscosity of the vinyl silicone oil in component A is 5000-5500 mm at 25°C. 2 / s.

[0020] The modified vinyl silicone oil prepared by the present invention introduces rigid groups such as phenyl ether group and phenyl group, and a random copolymer of silylbenzene and methylsiloxane is obtained by reaction. The interaction between the chain structure of the random copolymer and the main chain of the silicone rubber improves the flexibility of the chain, increases the deformation between the silicon oxygen bond and the organic group, and thus increases the elasticity; in addition, the modified vinyl silicone oil can also react with the hydroxyl group on the surface of white carbon black, reduces the number of surface silicon hydroxyl groups, increases the structure of white carbon black, increases the contact surface between the particles and the rubber material, and increases the number of bonding points.

[0021] In some embodiments, the mass ratio of 1,4-bis(dimethylhydroxysilyl)benzene to 4,4'-bis(dimethylhydroxysilyl)diphenyl ether is 1:(0.8-1.2).

[0022] The present invention controls the viscosity of the obtained modified vinyl silicone oil to be between 3000 and 5000 mm by controlling the ratio of 1,4-bis(dimethylhydroxysilyl)benzene to 4,4'-bis(dimethylhydroxysilyl)diphenyl ether. 2 / s, so that the vinyl silicone oil of component A and component B forms a high and low viscosity combination, which not only improves the processability of liquid silicone but also makes the prepared silicone breast pad have better mechanical properties.

[0023] In some embodiments, the cyclotetrasiloxane mixture comprises octamethylcyclotetrasiloxane and tetramethyltetraphenylcyclotetrasiloxane.

[0024] Preferably, the mass ratio of octamethylcyclotetrasiloxane to tetramethyltetraphenylcyclotetrasiloxane is 1:(1.0-1.5).

[0025] The basis for the modified vinyl silicone oil of the present invention to improve the elasticity of silicone lies in the high phenyl content. For this reason, the present invention introduces more phenyl groups through a specifically selected cyclotetrasiloxane mixture, so that the interaction between the obtained modified vinyl silicone oil and the main chain of silicone is enhanced; at the same time, by controlling the amount of phenyl groups introduced, the degree of vulcanization is maintained and the occurrence of a decrease in resilience caused by the large volume steric hindrance of phenyl groups is avoided; in addition, the cyclotetrasiloxane mixture also helps to uniformly foam the silicone in the later stage, thereby improving the air permeability.

[0026] In some embodiments, the hydroxyl content of the hydroxy silicone oil is 1-2%.

[0027] Another aspect of the present invention provides a method for preparing the above-mentioned silicone breast pad, which specifically comprises the following steps:

[0028] (1) Material preparation: mixing component A and component B to obtain liquid silicone rubber; (2) Molding: injecting the liquid silicone rubber obtained in step (1) to obtain a silicone breast pad body; (3) Trimming: trimming and punching the silicone breast pad body obtained in step (2) in turn to obtain the breathable and lightweight silicone breast pad.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The present invention provides a silicone breast pad which is light, elastic, highly breathable and safe, and the production process is non-toxic, harmless and does not produce any harmful substances.

[0031] 2. The present invention utilizes vinyl MQ silicone resin and platinum catalyst to work synergistically, effectively exerting a reinforcing effect, while not causing the viscosity of the system to increase too quickly, which is beneficial to subsequent operations.

[0032] 3. The present invention introduces rigid groups such as phenyl ether and phenyl into the vinyl silicone oil, and the interaction between the formed chain structure and the main chain of the silicone rubber improves the flexibility of the chain, increases the deformation between the silicon oxygen bond and the organic group, and further improves the elasticity of the silicone breast pad; the vinyl silicone oil also reacts with the hydroxyl groups on the surface of silica, reduces the number of surface silanol groups, increases the structure of silica, increases the contact area between the particles and the rubber, and increases the number of bonding points.

[0033] 4. The present invention controls the viscosity of the modified vinyl silicone oil so that the vinyl silicone oils of component A and component B form a high-low viscosity combination, which not only improves the processability of the liquid silicone but also enables the prepared silicone breast pad to have better mechanical properties.

[0034] 5. The present invention improves the elasticity and air permeability of the silicone breast pad by using a specifically selected cyclotetrasiloxane mixture. DETAILED DESCRIPTION

[0035] The present invention will be described below in conjunction with specific embodiments. It should be noted that the following embodiments are examples of the present invention and are only used to illustrate the present invention, but not to limit the present invention. Other combinations and various modifications within the concept of the present invention may be performed without departing from the spirit or scope of the present invention.

[0036] In order to facilitate those skilled in the art to implement the present invention, some raw materials and manufacturers of the embodiments are described as follows:

[0037] Vinyl MQ silicone resin was purchased from Hubei Longsheng Sihai New Materials Co., Ltd. with the brand name SH-5202N;

[0038] The model of white carbon black is Wacker N20, with a particle size of 12nm;

[0039] The hydroxyl content of hydroxy silicone oil is 1.6%;

[0040] Double-terminated vinyl silicone oil was purchased from Ningbo Runhe High-tech Materials Technology Co., Ltd., model RH-Vi304, viscosity 5250±250mm 2 / s;

[0041] Vinyl double head was purchased from Guangzhou Shuangtao Fine Chemical Co., Ltd.;

[0042] The dimethyl silicone oil model is 201-1000 and can be purchased from any manufacturer.

[0043] Preparation Example 1

[0044] The preparation steps of modified vinyl silicone oil-A are as follows:

[0045] Under nitrogen protection, 100g of 1,4-bis(dimethylhydroxysilyl)benzene, 100g of 4,4'-bis(dimethylhydroxysilyl)diphenyl ether, 200g of octamethylcyclotetrasiloxane, 200g of tetramethyltetraphenylcyclotetrasiloxane and 15g of vinyl double-capped were stirred at 100°C for 30min, and then 13.5g of tetramethylammonium hydroxide was added. After stirring for 40min, the mixture was evacuated and kept warm for 2h, then heated to 155°C for 1h, then heated to 175°C for 1h, and cooled to room temperature to obtain modified vinyl silicone oil-A.

[0046] Preparation Example 2

[0047] The preparation steps of modified vinyl silicone oil-B are as follows:

[0048] Under nitrogen protection, 100g of 1,4-bis(dimethylhydroxysilyl)benzene, 100g of 4,4'-bis(dimethylhydroxysilyl)diphenyl ether, 400g of octamethylcyclotetrasiloxane and 15g of vinyl double-capped were stirred at 100°C for 30min, and then 13.5g of tetramethylammonium hydroxide was added. After stirring for 40min, the mixture was evacuated and kept warm for 2h, then heated to 155°C for 1h, then heated to 175°C for 1h, and cooled to room temperature to obtain modified vinyl silicone oil-B.

[0049] Preparation Example 3

[0050] The preparation steps of modified vinyl silicone oil-C are as follows:

[0051] Under nitrogen protection, 100g of 1,4-bis(dimethylhydroxysilyl)benzene, 100g of 4,4'-bis(dimethylhydroxysilyl)diphenyl ether, 400g of tetramethyltetraphenylcyclotetrasiloxane and 15g of vinyl double-capped were stirred at 100°C for 30min, and then 13.5g of tetramethylammonium hydroxide was added. After stirring for 40min, the mixture was evacuated and kept warm for 2h, then heated to 155°C for 1h, then heated to 175°C for 1h, and cooled to room temperature to obtain modified vinyl silicone oil-C.

[0052] Preparation Example 4

[0053] The preparation steps of modified vinyl silicone oil-D are as follows:

[0054] The difference between this preparation example and preparation example 1 is that 75 g of 4,4'-bis(dimethylhydroxysilyl)diphenyl ether was used.

[0055] Preparation Example 5

[0056] The preparation steps of modified vinyl silicone oil-E are as follows:

[0057] The difference between this preparation example and preparation example 1 is that 125 g of 4,4'-bis(dimethylhydroxysilyl)diphenyl ether was used.

[0058] Table 1 Viscosity of modified vinyl silicone oil

[0059] Modified vinyl silicone oil A B C D E <![CDATA[Viscosity at 25°C (mm 2 / s)]]> 4120±50 3370±50 4610±50 2890±50 5450±50

[0060] Example 1

[0061] A breathable and lightweight silicone breast pad, comprising a component A and a component B in a mass ratio of 1:8. In parts by weight, component A comprises 20 parts of double-terminal vinyl silicone oil, 12 parts of dimethyl silicone oil, 38 parts of white carbon black, 38 parts of vinyl MQ silicone resin, 0.015 parts of Karstedt catalyst and 2 parts of azodicarbonamide; component B comprises 60 parts of modified vinyl silicone oil-A, 40 parts of hydroxy silicone oil and 38 parts of diethyl fumarate.

[0062] The preparation method of the silicone breast pad in this embodiment specifically comprises the following steps:

[0063] (1) Material preparation: Mix component A and component B to obtain liquid silicone rubber;

[0064] (2) Molding: The liquid silicone rubber obtained in step (1) is subjected to injection molding to obtain a silicone breast pad body;

[0065] (3) Trimming: The silicone breast pad body obtained in step (2) is trimmed and punched in sequence to obtain a breathable and lightweight silicone breast pad.

[0066] Example 2

[0067] A breathable and lightweight silicone breast pad, comprising a component A and a component B in a mass ratio of 1:6. In parts by weight, component A comprises 16 parts of double-terminal vinyl silicone oil, 8 parts of dimethyl silicone oil, 32 parts of white carbon black, 32 parts of vinyl MQ silicone resin, 0.01 parts of Karstedt catalyst and 1 part of azodicarbonamide; component B comprises 55 parts of modified vinyl silicone oil-A, 35 parts of hydroxy silicone oil and 32 parts of diethyl fumarate.

[0068] The preparation method of this embodiment is the same as that of embodiment 1.

[0069] Example 3

[0070] A breathable and lightweight silicone breast pad, comprising a component A and a component B in a mass ratio of 1:9. In parts by weight, component A comprises 24 parts of double-terminal vinyl silicone oil, 16 parts of dimethyl silicone oil, 44 parts of white carbon black, 46 parts of vinyl MQ silicone resin, 0.02 parts of Karstedt catalyst and 3 parts of azodicarbonamide; component B comprises 65 parts of modified vinyl silicone oil-A, 45 parts of hydroxy silicone oil and 44 parts of diethyl fumarate.

[0071] The preparation method of this embodiment is the same as that of embodiment 1.

[0072] Example 4

[0073] This embodiment provides a breathable and lightweight silicone breast pad and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified vinyl silicone oil-A in component B is replaced by an equal portion of modified vinyl silicone oil-B.

[0074] Example 5

[0075] This embodiment provides a breathable and lightweight silicone breast pad and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified vinyl silicone oil-A in component B is replaced by an equal portion of modified vinyl silicone oil-C.

[0076] Example 6

[0077] This embodiment provides a breathable and lightweight silicone breast pad and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified vinyl silicone oil-A in component B is replaced by an equal portion of modified vinyl silicone oil-D.

[0078] Example 7

[0079] This embodiment provides a breathable and lightweight silicone breast pad and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified vinyl silicone oil-A in component B is replaced by an equal portion of modified vinyl silicone oil-E.

[0080] Example 8

[0081] This embodiment provides a breathable and lightweight silicone breast pad and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified vinyl silicone oil-A in component B is replaced by an equal portion of double-terminated vinyl silicone oil.

[0082] Performance Testing

[0083] 1. Elasticity test

[0084] According to the standard ASTM D638-22 "Standard Test Method for Tensile Properties of Plastics", the elastic elongation test was performed on the silicone breast pad provided in each embodiment.

[0085] 2. Air permeability test

[0086] The liquid silicone rubber provided in step (1) of each embodiment was molded into a film of 10 cm×10 cm×1 mm, and the oxygen permeability T0 was tested according to the "Standard Test for Oxygen Permeability of Films" (ASTM D3985). The test conditions were 24 h, 0.1 MPa, and the sample area (circular): 50 cm 2 .

[0087] The results are shown in Table 2.

[0088] Table 2 Performance test results

[0089] Elastic elongation (%) <![CDATA[T0(cm 3 / m 2 ·24h·0.1MPa)]]> Example 1 554 388 Example 2 529 365 Example 3 537 371 Example 4 516 354 Example 5 492 337 Example 6 473 335 Example 7 441 323 Example 8 380 302

[0090] From the data in Table 1, it can be seen that the silicone breast pads in Examples 1 to 3 have good elasticity and air permeability. Compared with Example 1, the modified vinyl silicone oil used in Example 4 did not add tetramethyltetraphenylcyclotetrasiloxane in the preparation, and Example 5 did not add octamethylcyclotetrasiloxane. Both of the above used a single cyclotetrasiloxane, resulting in decreased air permeability. From the data changes in elastic elongation, it can be seen that the former reduces the content of phenyl, weakens the interaction between the modified vinyl silicone oil and the main chain of silicone, and reduces elasticity; the latter introduces too many phenyl groups, which may bring about a steric hindrance effect, resulting in decreased elasticity of silicone.

[0091] Compared with Example 1, the modified vinyl silicone oil used in Examples 6-7 changed the amount of 4,4'-bis(dimethylhydroxysilyl)diphenyl ether in the preparation. As can be seen from the data in Table 1, the viscosity of the two exceeded the control range and could not form a coordinated high-low viscosity match with the vinyl silicone oil of component A, resulting in decreased elasticity and air permeability. Compared with Example 1, Example 8 replaced the modified vinyl silicone oil with commercially available double-terminal vinyl silicone oil, resulting in a significant decrease in elasticity and air permeability.

[0092] The embodiments described above do not impose any form of limitation on the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A breathable and lightweight silicone breast pad, the raw material comprises component A and component B in a mass ratio of 1: (6-9), characterized in that: In parts by weight, the component B comprises 55 to 65 parts of modified vinyl silicone oil, 35 to 45 parts of hydroxy silicone oil and 32 to 44 parts of inhibitor; the component A comprises 16 to 24 parts of vinyl silicone oil, 8 to 16 parts of dimethyl silicone oil, 32 to 44 parts of white carbon black, 32 to 46 parts of MQ silicone resin, 0.01 to 0.02 parts of catalyst and 1 to 3 parts of foaming agent.

2. The breathable and lightweight silicone breast pad according to claim 1, characterized in that: The elastic elongation of the breathable and lightweight silicone breast pad is ≥380%, and the oxygen permeability T0 is ≥300cm 3 / m 2 ·24h·0.1MPa.

3. The breathable and lightweight silicone breast pad according to claim 1, characterized in that: The catalyst is any one of a platinum catalyst, an amine catalyst and an organotin catalyst.

4. The breathable and lightweight silicone breast pad according to claim 1, characterized in that: The particle size of the white carbon black is 5 to 50 nm.

5. The breathable and lightweight silicone breast pad according to claim 1, characterized in that: The MQ silicone resin is one or more of methyl MQ silicone resin, vinyl MQ silicone resin or phenyl MQ silicone resin.

6. The breathable and lightweight silicone breast pad according to claim 1, characterized in that: The preparation steps of the modified vinyl silicone oil are as follows: Under nitrogen protection, 1,4-bis(dimethylhydroxysilyl)benzene, 4,4'-bis(dimethylhydroxysilyl)diphenyl ether, cyclotetrasiloxane mixture and vinyl double cap are stirred at 90-120° C. for 20-40 min, then tetramethylammonium hydroxide is added, and after stirring for 0.5-1 h, vacuum is evacuated, and the mixture is kept warm for 1-2 h. The mixture is then heated to 150-160° C. and kept warm for 0.5-1 h, and then heated to 170-180° C. and kept warm for 1-2 h, and then cooled to room temperature to obtain the modified vinyl silicone oil.

7. The breathable and lightweight silicone breast pad according to claim 6, characterized in that: The mass ratio of the 1,4-bis(dimethylhydroxysilyl)benzene to 4,4'-bis(dimethylhydroxysilyl)diphenyl ether is 1:(0.8-1.2).

8. The breathable and lightweight silicone breast pad according to claim 6, characterized in that: The cyclotetrasiloxane mixture comprises octamethylcyclotetrasiloxane and tetramethyltetraphenylcyclotetrasiloxane.

9. The breathable and lightweight silicone breast pad according to claim 1, characterized in that: The hydroxyl content of the hydroxy silicone oil is 1-2%.

10. A method for preparing the breathable and lightweight silicone breast pad according to any one of claims 1 to 9, characterized in that: The specific steps include: (1) Material preparation: mixing component A and component B to obtain liquid silicone rubber; (2) Molding: injecting the liquid silicone rubber obtained in step (1) to obtain a silicone breast pad body; (3) Trimming: trimming and punching the silicone breast pad body obtained in step (2) in turn to obtain the breathable and lightweight silicone breast pad.