Oil-resistant nitrile rubber stopper for cosmetics and preparation method thereof

Abstract

The present invention discloses an oil-resistant nitrile butadiene rubber stopper for cosmetics and a preparation method thereof. The oil-resistant nitrile butadiene rubber stopper for cosmetics is prepared from the following raw materials, measured by mass: 90 to 110 parts of nitrile butadiene rubber, 50 to 65 parts of calcined kaolin, 0.1 to 4 parts of titanium dioxide, 0.1 to 0.5 parts of carbon black, 1 to 4 parts of vaseline, and 6 to 14.1 parts of a vulcanizing component; the raw materials of the vulcanizing component include 2 to 5 parts of phenolic resin HY-2055, 0.5 to 1.4 parts of stearic acid, 3 to 6 parts of zinc oxide, and 0.5 to 1.7 parts of antioxidant 1076. The present invention is based on nitrile butadiene rubber and improves the oil resistance of the prepared rubber stopper by using a specific ratio of titanium dioxide, carbon black, and vaseline, while optimizing the formula of the vulcanizing component.

Description

Technical Field

[0001] The invention relates to the technical field of cosmetics, in particular to a nitrile butadiene rubber stopper for oil-resistant cosmetics and a preparation method thereof. Background Art

[0002] Currently, most cosmetics are packaged in bottles. During use or storage, the emulsion inside the bottle frequently comes into contact with the top stopper. To prevent oily or water-based cosmetics from deteriorating due to prolonged contact with the stopper, stoppers must be made of materials with good oil or water resistance. Furthermore, the stopper must not affect the stability, effectiveness, or safety of the cosmetic itself during prolonged contact. This places high demands on rubber stoppers used in cosmetics.

[0003] For the packaging plugs of cosmetics and other preparations, butyl rubber with excellent moisture permeability resistance is usually used as the plug material to prevent them from being stored in the container. However, traditional nitrile rubber plugs will swell, deform, and precipitate after long-term contact with oily cosmetics. These phenomena are not conducive to the long-term storage of oily cosmetics. Therefore, it is necessary to propose a new rubber plug preparation process to solve the above-mentioned existing problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a nitrile butadiene rubber stopper for oil-resistant cosmetics and a preparation method thereof, so as to solve the problem that the existing nitrile butadiene rubber stopper will swell, deform, precipitate and the like after long-term contact with oily cosmetics.

[0005] To solve the above technical problems, the first solution provided by the present invention is: an oil-resistant nitrile rubber stopper for cosmetics, which is made from the following raw materials, in parts by mass: 90 to 110 parts of nitrile rubber, 50 to 65 parts of calcined kaolin, 0.1 to 4 parts of titanium dioxide, 0.1 to 0.5 parts of carbon black, 1 to 4 parts of vaseline, and 6 to 14.1 parts of vulcanizing components; the vulcanizing components include phenolic resin HY-2055, stearic acid, zinc oxide and antioxidant 1076.

[0006] The raw materials of the vulcanization component are as follows: 2 to 5 parts of phenolic resin HY-2055, 0.5 to 1.4 parts of stearic acid, 3 to 6 parts of zinc oxide and 0.5 to 1.7 parts of antioxidant 1076.

[0007] Preferably, the composition is prepared from the following raw materials, calculated by weight: 95-105 parts of nitrile butadiene rubber, 56-60 parts of calcined kaolin, 1-3 parts of titanium dioxide, 0.1-0.5 parts of carbon black, 1-3 parts of vaseline, and 8.4-13.4 parts of a vulcanizing component. The raw materials for the vulcanizing component are, calculated by weight, 3-5 parts of phenolic resin HY-2055, 0.8-1.2 parts of stearic acid, 4-6 parts of zinc oxide, and 0.6-1.2 parts of antioxidant 1076.

[0008] More preferably, the following raw materials are used, by weight: 100 parts nitrile rubber, 58 parts calcined kaolin, 2 parts titanium dioxide, 0.3 parts carbon black, 2 parts vaseline, and 11 parts vulcanizing component. The raw materials for the vulcanizing component are, by weight: 4 parts phenolic resin HY-2055, 1 part stearic acid, 5 parts zinc oxide, and 1 part antioxidant 1076.

[0009] In order to solve the above technical problems, the second solution provided by the present invention is: a preparation method of nitrile butadiene rubber stoppers for oil-resistant cosmetics, which is used to prepare the nitrile butadiene rubber stoppers for oil-resistant cosmetics in the aforementioned first solution, comprising the following steps: S1, uniformly mixing nitrile butadiene rubber, calcined kaolin, titanium dioxide, carbon black, vaseline, and vulcanizing components according to a proportion to obtain a mixture; S2, the mixture is subjected to internal mixing and open mixing in sequence to obtain a preformed body; S3, the preformed body is vulcanized by an injection vulcanization molding process, and the oil-resistant nitrile butadiene rubber stoppers for cosmetics are obtained after punching and cleaning.

[0010] Preferably, in step S1, a stirrer is used for stirring and mixing, with a rotation speed of 900 to 1200 rpm and a stirring time of 10 to 20 minutes.

[0011] In step S2, the mixed materials in step S1 are further mixed evenly using an internal mixer, and then introduced into an open mixer to produce a preformed embryo.

[0012] Preferably, the temperature of the internal mixer is set at 80-100°C, and the outlet discharge temperature of the open mixer is 70-80°C.

[0013] Preferably, the residence time ratio of the materials in the internal mixer and the open mixer is 1-1.2:1, and the total residence time of the materials in the internal mixer and the open mixer is 15-20 minutes.

[0014] Preferably, in step S3, the conditions of the injection vulcanization molding process are: vulcanization temperature of 180-190°C, vulcanization pressure of 220-240 bar, and injection tube temperature of 75-95°C.

[0015] The beneficial effects of the present invention are as follows: Different from the prior art, the present invention provides an oil-resistant nitrile rubber stopper for cosmetics and a preparation method thereof. Based on nitrile rubber, the oil resistance of the prepared rubber stopper is improved by adopting a specific ratio of titanium dioxide, carbon black, and vaseline, and optimizing the formula of the vulcanization component. DETAILED DESCRIPTION

[0016] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0017] The first solution provided by the present invention provides an oil-resistant nitrile butadiene rubber stopper for cosmetics, which is made from the following raw materials, calculated by weight: 90-110 parts nitrile butadiene rubber, 50-65 parts calcined kaolin, 0.1-4 parts titanium dioxide, 0.1-0.5 parts carbon black, 1-4 parts petrolatum, and 6-14.1 parts of a vulcanizing component; the vulcanizing component includes phenolic resin HY-2055, stearic acid, zinc oxide, and antioxidant 1076. The raw materials for the vulcanizing component are as follows: 2-5 parts phenolic resin HY-2055, 0.5-1.4 parts stearic acid, 3-6 parts zinc oxide, and 0.5-1.7 parts antioxidant 1076.

[0018] The preferred raw material formula for oil-resistant nitrile rubber stoppers for cosmetics is, by weight, 95-105 parts nitrile rubber, 56-60 parts calcined kaolin, 1-3 parts titanium dioxide, 0.1-0.5 parts carbon black, 1-3 parts petrolatum, and 8.4-13.4 parts of a vulcanizing component. The vulcanizing component comprises 3-5 parts phenolic resin HY-2055, 0.8-1.2 parts stearic acid, 4-6 parts zinc oxide, and 0.6-1.2 parts antioxidant 1076.

[0019] A further preferred formula for oil-resistant nitrile rubber stoppers for cosmetics is, by weight, 100 parts nitrile rubber, 58 parts calcined kaolin, 2 parts titanium dioxide, 0.3 parts carbon black, 2 parts petrolatum, and 11 parts of a vulcanizing component. The vulcanizing component comprises, by weight, 4 parts phenolic resin HY-2055, 1 part stearic acid, 5 parts zinc oxide, and 1 part antioxidant 1076.

[0020] The second solution provided by the present invention provides a method for preparing an oil-resistant nitrile butadiene rubber stopper for cosmetics. The method is used to prepare the oil-resistant nitrile butadiene rubber stopper for cosmetics in the first solution, comprising the following steps:

[0021] S1, nitrile butadiene rubber, calcined kaolin, titanium dioxide, carbon black, vaseline, and a vulcanizing component are uniformly mixed according to a proportion to obtain a mixture. In this step, a stirrer is used to stir and mix the nitrile butadiene rubber, calcined kaolin, titanium dioxide, carbon black, vaseline, and a vulcanizing component according to a proportion at a rotation speed of 900 to 1200 rpm for 10 to 20 minutes to obtain a mixture.

[0022] S2: The mixture is then subjected to internal and external mixing to obtain a preformed body. In this step, the mixture from step S1 is further mixed uniformly using an internal mixer, and then introduced into an open mixer to produce a preformed body. The internal mixer is set to a temperature of 80-100°C, the outlet temperature of the open mixer is 70-80°C, the residence time of the materials in the internal mixer and the open mixer is a ratio of 1-1.2:1, and the total residence time of the materials in the internal mixer and the open mixer is 15-20 minutes.

[0023] S3, vulcanize the preformed body by injection vulcanization molding process, and after punching and cleaning, obtain the oil-resistant nitrile butadiene rubber stopper for cosmetics. In this step, the preformed body is vulcanized by injection vulcanization molding process. The conditions of injection vulcanization molding process are: vulcanization temperature of 180-190℃, vulcanization pressure of 220-240bar, and injection tube temperature of 75-95℃. After vulcanization, punching is performed as required and then cleaned to obtain the oil-resistant nitrile butadiene rubber stopper for cosmetics.

[0024] The following examples describe in detail the preparation method and effects of the oil-resistant nitrile rubber stopper for cosmetics. The raw materials used in the following examples are: nitrile rubber JSR N240S (Japan); calcined kaolin (Lixin, Inner Mongolia); anatase titanium dioxide (Nanjing Taibai Chemical); vaseline (Jinxin Chemical, Guangdong); phenolic resin HY-2055 (Shanxi Chemical Research Institute); zinc oxide (Jinghua Chemical, Shanghai); antioxidant 1076 (Kain Chemical, Shanghai); stearic acid (Xindongyi Chemical, Wuhan); and carbon black N774 (Yakla, Xinjiang).

[0025] Example 1

[0026] The specific steps for preparing the rubber stopper in this embodiment are as follows:

[0027] (1) 100 parts of nitrile rubber, 58 parts of calcined kaolin, 2 parts of titanium dioxide, 0.3 parts of carbon black, 2 parts of vaseline, and 11 parts of vulcanizing components (the raw materials of the vulcanizing components are as follows: 4 parts of phenolic resin HY-2055, 1 part of stearic acid, 5 parts of zinc oxide, and 1 part of antioxidant 1076) are taken as raw materials for preparation.

[0028] (2) The above raw materials were stirred and mixed using a stirrer at a rotation speed of 1200 rpm for 10 min to obtain a mixture.

[0029] (3) The above-mentioned mixture is further mixed uniformly by using an internal mixer, the temperature of the internal mixer is set to 90°C, and the residence time of the material in the internal mixer is 8 minutes; then the mixed material is introduced into an open mixer to produce a preformed embryo, the outlet discharge temperature of the open mixer is 75°C, and the residence time of the material in the open mixer is 8 minutes.

[0030] (4) The preformed body is vulcanized by injection vulcanization molding process, with a vulcanization temperature of 180°C, a vulcanization pressure of 240 bar, and an injection tube temperature of 80°C (specifically, the tube body temperature is tested); after vulcanization is completed, punching is performed as required, and then cleaned to obtain a rubber stopper sample.

[0031] Example 2

[0032] The specific steps for preparing the rubber stopper in this embodiment are as follows:

[0033] (1) 100 parts by mass of nitrile rubber, 60 parts by mass of calcined kaolin, 2 parts by mass of titanium dioxide, 0.3 parts by mass of carbon black, 1 part by mass of vaseline, and 11 parts by mass of vulcanizing component (the raw materials of the vulcanizing component are as follows: 4 parts by mass of phenolic resin HY-2055, 1 part by mass of stearic acid, 5 parts by mass of zinc oxide, and 1 part by mass of antioxidant 1076) are used as raw materials for preparation.

[0034] (2) The above raw materials were stirred and mixed using a stirrer at a rotation speed of 1200 rpm for 10 min to obtain a mixture.

[0035] (3) The above-mentioned mixture is further mixed uniformly by using an internal mixer, the temperature of the internal mixer is set to 90°C, and the residence time of the material in the internal mixer is 8 minutes; then the mixed material is introduced into an open mixer to produce a preformed embryo, the outlet discharge temperature of the open mixer is 75°C, and the residence time of the material in the open mixer is 8 minutes.

[0036] (4) The preformed body is vulcanized by injection vulcanization molding process, with a vulcanization temperature of 180°C, a vulcanization pressure of 240 bar, and an injection tube temperature of 80°C (specifically, the tube body temperature is tested); after vulcanization is completed, punching is performed as required, and then cleaned to obtain a rubber stopper sample.

[0037] Example 3

[0038] (1) 100 parts by mass of nitrile rubber, 58 parts by mass of calcined kaolin, 2 parts by mass of titanium dioxide, 0.3 parts by mass of carbon black, 2 parts by mass of vaseline, and 7 parts by mass of a vulcanizing component (the raw materials of the vulcanizing component are as follows: 2 parts by mass of phenolic resin HY-2055, 1 part by mass of stearic acid, 3 parts by mass of zinc oxide, and 1 part by mass of antioxidant 1076) are used as raw materials for preparation.

[0039] (2) The above raw materials were stirred and mixed using a stirrer at a rotation speed of 1200 rpm for 10 min to obtain a mixture.

[0040] (3) The above-mentioned mixture is further mixed uniformly by using an internal mixer, the temperature of the internal mixer is set to 90°C, and the residence time of the material in the internal mixer is 8 minutes; then the mixed material is introduced into an open mixer to produce a preformed embryo, the outlet discharge temperature of the open mixer is 75°C, and the residence time of the material in the open mixer is 8 minutes.

[0041] (4) The preformed body is vulcanized by injection vulcanization molding process, with a vulcanization temperature of 180°C, a vulcanization pressure of 240 bar, and an injection tube temperature of 80°C (specifically, the tube body temperature is tested); after vulcanization is completed, punching is performed as required, and then cleaned to obtain a rubber stopper sample.

[0042] Comparative Example 1

[0043] The specific steps for preparing the rubber stopper in this comparative example are as follows:

[0044] (1) 100 parts by mass of nitrile rubber, 58 parts by mass of calcined kaolin, 2 parts by mass of titanium dioxide, 0.3 parts by mass of carbon black, and 11 parts by mass of a vulcanizing component (the raw materials of the vulcanizing component are as follows: 4 parts by mass of phenolic resin HY-2055, 1 part by mass of stearic acid, 5 parts by mass of zinc oxide, and 1 part by mass of an antioxidant 1076) are used as raw materials for preparation.

[0045] (2) The above raw materials were stirred and mixed using a stirrer at a rotation speed of 1200 rpm for 10 min to obtain a mixture.

[0046] (3) The above-mentioned mixture is further mixed uniformly by using an internal mixer, the temperature of the internal mixer is set to 90°C, and the residence time of the material in the internal mixer is 8 minutes; then the mixed material is introduced into an open mixer to produce a preformed embryo, the outlet discharge temperature of the open mixer is 75°C, and the residence time of the material in the open mixer is 8 minutes.

[0047] (4) The preformed body is vulcanized by injection vulcanization molding process, with a vulcanization temperature of 180°C, a vulcanization pressure of 240 bar, and an injection tube temperature of 80°C (specifically, the tube body temperature is tested); after vulcanization is completed, punching is performed as required, and then cleaned to obtain a rubber stopper sample.

[0048] Comparative Example 2

[0049] The specific steps for preparing the rubber stopper in this comparative example are as follows:

[0050] (1) 100 parts by mass of nitrile rubber, 58 parts by mass of calcined kaolin, 2 parts by mass of titanium dioxide, 2 parts by mass of vaseline, and 11 parts by mass of a vulcanizing component (the raw materials of the vulcanizing component are as follows: 4 parts by mass of phenolic resin HY-2055, 1 part by mass of stearic acid, 5 parts by mass of zinc oxide, and 1 part by mass of an antioxidant 1076) are used as raw materials for preparation.

[0051] (2) The above raw materials were stirred and mixed using a stirrer at a rotation speed of 1200 rpm for 10 min to obtain a mixture.

[0052] (3) The above-mentioned mixture is further mixed uniformly by using an internal mixer, the temperature of the internal mixer is set to 90°C, and the residence time of the material in the internal mixer is 8 minutes; then the mixed material is introduced into an open mixer to produce a preformed embryo, the outlet discharge temperature of the open mixer is 75°C, and the residence time of the material in the open mixer is 8 minutes.

[0053] (4) The preformed body is vulcanized by injection vulcanization molding process, with a vulcanization temperature of 180°C, a vulcanization pressure of 240 bar, and an injection tube temperature of 80°C (specifically, the tube body temperature is tested); after vulcanization is completed, punching is performed as required, and then cleaned to obtain a rubber stopper sample.

[0054] The rubber stopper samples prepared in Examples 1 to 4 were subjected to oil resistance tests. Specifically, they were immersed in mineral oil at room temperature and the mass change rate after 30 days of immersion was tested. The results are shown in Table 1. Under normal circumstances, when the mass change rate is greater than 5%, local swelling and deformation will appear, so as to evaluate the durability of the prepared rubber stopper samples.

[0055] Table 1

[0056] Oil immersion mass change rate Is the mass change rate greater than 5%? Surface state Example 1 2.14％ no No obvious swelling was observed, no precipitates Example 2 3.05％ no No obvious swelling was observed, no precipitates Example 3 2.92％ no No obvious swelling was observed, no precipitates Comparative Example 1 6.91％ yes Local swelling and a small amount of precipitation Comparative Example 2 6.58％ yes Local swelling, no precipitation

[0057] It can be seen from Table 1 that the mass change rates of Examples 1 to 3 after 30 days of oil immersion are all less than 5%, and there is no obvious swelling phenomenon and no precipitate; while after removing the vaseline and carbon black components from Comparative Examples 1 and 2 respectively, the mass change rates after 30 days of oil immersion are greater than 5%, and local swelling and precipitation phenomena occur, indicating that the introduction of vaseline and carbon black components can enhance the oil resistance of the prepared nitrile rubber stopper.

[0058] Different from the existing technology, the present invention provides an oil-resistant nitrile rubber stopper for cosmetics and a preparation method thereof. Based on nitrile rubber, the oil resistance of the prepared rubber stopper is improved by adopting a specific ratio of titanium dioxide, carbon black, and vaseline, and optimizing the formula of the vulcanization component.

[0059] It should be noted that the above embodiments all belong to the same inventive concept, and the description of each embodiment has its own focus. For any details not described in individual embodiments, reference may be made to the description in other embodiments.

[0060] The above-described embodiments merely illustrate the implementation methods of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A nitrile rubber stopper for oil-resistant cosmetics, characterized in that: The following raw materials are prepared, in parts by mass: 100 parts of nitrile rubber, 58 parts of calcined kaolin, 2 parts of titanium dioxide, 0.3 parts of carbon black, 2 parts of vaseline, and 11 parts of a vulcanizing component; The raw materials of the vulcanization component are as follows: 4 parts of phenolic resin HY-2055, 1 part of stearic acid, 5 parts of zinc oxide and 1 part of antioxidant 1076.

2. A method for preparing the oil-resistant nitrile rubber stopper for cosmetics according to claim 1, characterized in that: The steps include: S1, uniformly mixing nitrile butadiene rubber, calcined kaolin, titanium dioxide, carbon black, vaseline, and a vulcanizing component according to a proportion to obtain a mixture; S2, the mixed material is subjected to internal mixing and open mixing in sequence to obtain a preformed body; S3, vulcanizing the preformed body by injection vulcanization molding process, and obtaining the oil-resistant nitrile rubber plug for cosmetics after punching and cleaning.

3. The method for preparing the oil-resistant nitrile rubber stopper for cosmetics according to claim 2, characterized in that: In the step S1, a stirrer is used for stirring and mixing, with a rotation speed of 900-1200 rpm and a stirring time of 10-20 min.

4. The method for preparing the oil-resistant nitrile rubber stopper for cosmetics according to claim 2, characterized in that: In step S2, the mixed materials in step S1 are further mixed uniformly using an internal mixer, and then introduced into an open mixer to extract the mixed materials into a preformed embryonic body.

5. The method for preparing the oil-resistant nitrile rubber stopper for cosmetics according to claim 2, characterized in that: The temperature of the internal mixer is set at 80-100°C, and the outlet discharge temperature of the open mixer is set at 70-80°C.

6. The method for preparing the oil-resistant nitrile rubber stopper for cosmetics according to claim 2, characterized in that: The residence time ratio of the materials in the internal mixer and the open mixer is 1-1.2:1, and the total residence time of the materials in the internal mixer and the open mixer is 15-20 min.

7. The method for preparing the oil-resistant nitrile rubber stopper for cosmetics according to claim 2, characterized in that: In step S3, the injection vulcanization molding process is carried out under the following conditions: a vulcanization temperature of 180-190° C., a vulcanization pressure of 220-240 bar, and an injection tube temperature of 75-95° C.