Oil-resistant polyvinyl chloride glove and preparation process thereof

Abstract

The invention relates to the technical field of polyvinyl chloride glove preparation, and discloses an oil-resistant polyvinyl chloride glove and a preparation process thereof, the oil-resistant polyvinyl chloride glove comprises the following raw materials by weight: 100-120 parts of polyvinyl chloride paste resin, 20-60 parts of a plasticizer, 2-10 parts of a stabilizer, and 5-15 parts of a combined additive; the preparation method of the combined additive comprises the following steps: drying the nano silicon dioxide at 110 DEG C for 3 hours to remove moisture; adding the dried nano silicon dioxide into a high-speed mixer, and stirring for 7 minutes at the rotating speed of 900 revolutions per minute; slowly adding the maleic anhydride grafted polyolefin elastomer into the high-speed mixer, continuously mixing and stirring with the nano silicon dioxide for 13 minutes, and controlling the mixing temperature at 140 DEG C to obtain the combined additive. According to the oil-resistant polyvinyl chloride glove and the preparation process thereof, the tensile strength of the glove is improved through the specially designed combined additive.

Description

Technical Field

[0001] The invention relates to the technical field of polyvinyl chloride gloves preparation, in particular to oil-resistant polyvinyl chloride gloves and a preparation process thereof. Background Art

[0002] In the existing field of glove materials, rubber gloves such as nitrile rubber gloves have good oil resistance, but the cost is relatively high, and some people may be allergic to rubber. Ordinary polyvinyl chloride gloves are prone to swelling, softening, and even cracking when in contact with oily substances. This is mainly due to the molecular structure of polyvinyl chloride and the lack of optimization for oil resistance in traditional formulas. In order to improve the oil resistance of polyvinyl chloride gloves, previous studies have focused on the selection of plasticizers and stabilizers. Some studies have tried to use special plasticizers, such as phosphate plasticizers. Although the oil resistance has been improved to a certain extent, it often leads to a decrease in other properties, such as poor flexibility and poor low-temperature performance. In terms of stabilizers, different types of stabilizers have different effects on the thermal stability and weather resistance of polyvinyl chloride gloves, but relying solely on stabilizers is not enough. In addition, for the application of additives in polyvinyl chloride gloves, although some studies involve additives such as nanomaterials and elastomers, there are still deficiencies in the combined use and targeted modification of them to synergistically improve the tensile strength and oil resistance. For example, the dispersion problem of nanomaterials in polyvinyl chloride matrix often leads to the inability to fully exert its reinforcing effect, and the compatibility of elastomers with polyvinyl chloride and the balance between their own structure and oil resistance have not been well solved. Therefore, it is necessary to develop a new oil-resistant polyvinyl chloride glove and its preparation process. By rationally designing the combination of additives and optimizing the preparation process, while ensuring the comprehensive properties of the gloves such as good flexibility and tensile strength, its oil resistance is significantly improved to meet the growing needs of industrial protection and special applications. Summary of the invention

[0003] To achieve the above objectives, the present invention is implemented by the following technical scheme: an oil-resistant polyvinyl chloride glove and a preparation process thereof, comprising the following raw materials by weight: 100-120 parts of polyvinyl chloride paste resin, 20-60 parts of plasticizer, 2-10 parts of stabilizer, and 5-15 parts of combined additives; The preparation method of the combined additive comprises: The nano-silica was dried at 110°C for 3 hours to remove moisture; Add the dried nano-silica into a high-speed mixer and stir at 900 rpm for 7 minutes; The maleic anhydride grafted polyolefin elastomer was slowly added into a high-speed mixer, and was continuously mixed and stirred with the nano-silicon dioxide for 13 minutes, with the mixing temperature being controlled at 140° C., to obtain the composite additive.

[0004] Preferably, the plasticizer is one or more of dioctyl phthalate, dioctyl terephthalate, and dioctyl adipate.

[0005] Preferably, the stabilizer is one or more of a calcium-zinc stabilizer, a barium-zinc stabilizer, and an organic tin stabilizer.

[0006] Preferably, the combined additive consists of nano-silicon dioxide and modified polyolefin elastomer, and the modified polyolefin elastomer is maleic anhydride grafted polyolefin elastomer.

[0007] Preferably, the combination additive may also be replaced by a modified combination additive, and the preparation method of the modified combination additive comprises: The first step is to graft the surface of nano-silicon dioxide, disperse the nano-silicon dioxide in an organic solvent, add a silane coupling agent, stir and react at 70°C for 5 hours, filter, wash and dry after the reaction to obtain the surface-grafted nano-silicon dioxide; the silane coupling agent is vinyl triethoxysilane or γ-methacryloxypropyl trimethoxysilane; The second step is to synthesize the modified polyolefin elastomer, wherein the maleic anhydride grafted polyolefin elastomer and the small molecule compound containing an amino functional group are subjected to a grafting reaction in a solution in the presence of an initiator, the reaction temperature is 130° C., the reaction time is 4 hours, and after the reaction is completed, the solvent is removed to obtain the modified polyolefin elastomer; the small molecule compound containing an amino functional group is aminopropyltrimethoxysilane or N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane; The third step is to dry the surface-grafted nano-silica at 110°C for 3 hours to remove moisture; Step 4: Add the dried surface-grafted nano-silica into a high-speed mixer and stir at a speed of 900 rpm for 7 minutes; Step 5: slowly add the modified polyolefin elastomer into the high-speed mixer, and continue to mix and stir with the surface-grafted nano-silicon dioxide for 13 minutes, with the mixing temperature controlled at 140° C., to obtain the modified composite additive.

[0008] A preparation process of oil-resistant polyvinyl chloride gloves comprises the following steps: Step 1, after weighing the polyvinyl chloride paste resin, plasticizer, stabilizer, and modified combined additive by weight, first add the polyvinyl chloride paste resin into a closed mixing kettle with heating and stirring functions, turn on the stirring device, set the stirring speed to 300-500 rpm, and heat the mixing kettle at the same time to raise the temperature in the kettle to 30-60°C; then slowly add the stabilizer to the mixing kettle, and continue stirring for 3-5 minutes to ensure that the stabilizer is evenly dispersed in the polyvinyl chloride paste resin; then add the plasticizer to the mixing kettle at a uniform flow rate, and during the process of adding the plasticizer, continue stirring and monitor the temperature to maintain the temperature at 30-60°C. After the plasticizer is added, continue stirring for 5-8 minutes; finally, add the modified combined additive to the mixing kettle in equal amounts three times, with an interval of 2-3 minutes between each addition, and stir for 10-30 minutes after all are added to obtain a uniform mixture with good fluidity; Step 2: The mixture is transported to a dipping tank through a pipeline, and the pre-prepared glove mold is dipped into the mixture at a uniform and slow speed for 20-80 seconds to ensure that the surface of the mold is evenly covered with a layer of the mixture; Step 3: The impregnated glove blanks are transferred together with the mold to a plasticizing furnace for plasticizing treatment. The plasticizing furnace adopts segmented heating control. First, the glove blanks are kept in a low temperature section of 180-200°C for 1-3 minutes to initially plasticize and shape the glove blanks. Then, the glove blanks are kept in a medium temperature section of 200-220°C for 1-3 minutes to further promote the plasticizing reaction of the material and the regularity of the arrangement of the molecular chains. Finally, the glove blanks are kept in a high temperature section of 220-240°C for 1-4 minutes to ensure that the glove blanks are completely plasticized and various properties are stable. The entire plasticizing time is 3-10 minutes. Step 4: The plasticized gloves are transferred together with the mold to a cooling and demolding device for demolding. The demolded gloves are then trimmed, inspected and other post-processing steps to remove excess parts and defective products on the edge of the gloves to obtain oil-resistant polyvinyl chloride gloves.

[0009] Preferably, the temperature of the mixture in the dipping tank in step 2 is maintained at 20-80° C. by a constant temperature control system.

[0010] Preferably, in step 4, air cooling is first used to quickly cool the gloves to 80-100° C. to preliminarily shape the gloves, and then demoulding is performed.

[0011] The present invention provides an oil-resistant polyvinyl chloride glove and a preparation process thereof, which has the following beneficial effects: The oil-resistant polyvinyl chloride gloves and the preparation process thereof have significantly improved tensile strength. The tensile strength of the gloves can be increased to 20-35 MPa through the synergistic effect of specially designed combined additives, such as surface-grafted nano-silica and maleic anhydride-grafted polyolefin elastomers with further modified molecular chains. Compared with traditional polyvinyl chloride gloves, the gloves are significantly enhanced and can better withstand external tensile forces, reduce the risk of damage due to force during use, effectively extend the service life of the gloves, and broaden their application scenarios. The gloves are particularly suitable for working environments with high requirements for mechanical properties. While improving the tensile strength, the gloves can still maintain an elongation at break of 300%-600% through reasonable allocation of the proportions of various components and optimization of the interaction between the additives and the polyvinyl chloride body, and have good flexibility, ensuring that the user's hands can move freely during operation, and the accuracy and flexibility of the operation will not be affected by the gloves being too hard. After the gloves prepared by the special formula and process are immersed in specific oils and solvents for 48 hours, the performance index change rate does not exceed 20%, showing excellent oil and solvent resistance. This makes the gloves widely used in industries involving frequent contact with oil products, such as chemical, petroleum, and mechanical maintenance, effectively preventing oil products from corroding and penetrating the glove materials, providing users with reliable hand protection, and reducing the risk of skin damage and safety accidents caused by oil contact. The detailed and optimized preparation process, such as the precise control of the order of adding each raw material, stirring speed, temperature and time in the raw material mixing step, strict control of temperature and time during the dipping process, segmented heating control in the plasticizing stage, and reasonable setting of the cooling and demoulding process, make the entire production process highly controllable and stable. This is not only conducive to ensuring the consistency and stability of the quality of each batch of gloves, reducing the defective rate, and improving production efficiency, but also facilitates the flexible adjustment of process parameters according to actual needs, further optimizes product performance, and provides a strong guarantee for industrial large-scale production. DETAILED DESCRIPTION

[0012] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0013] In the first embodiment, the present invention provides a technical solution: an oil-resistant polyvinyl chloride glove, composed of the following raw materials by weight: 100 parts of polyvinyl chloride paste resin, 20 parts of plasticizer, 2 parts of stabilizer, and 5 parts of combined additives; The preparation method of the combined additive comprises: The nano-silica was dried at 110°C for 3 hours to remove moisture; Add the dried nano-silica into a high-speed mixer and stir at 900 rpm for 7 minutes; Slowly adding the maleic anhydride grafted polyolefin elastomer into a high-speed mixer, and continuing to mix and stir with the nano-silicon dioxide for 13 minutes, with the mixing temperature controlled at 140° C., to obtain the combined additive; A preparation process of oil-resistant polyvinyl chloride gloves comprises the following steps: Step 1, after weighing the polyvinyl chloride paste resin, plasticizer, stabilizer, and modified combined additive by weight, first add the polyvinyl chloride paste resin into a closed mixing kettle with heating and stirring functions, turn on the stirring device, set the stirring speed to 300 rpm, and heat the mixing kettle at the same time to raise the temperature in the kettle to 30°C; then slowly add the stabilizer to the mixing kettle, and continue stirring for 3 minutes to ensure that the stabilizer is evenly dispersed in the polyvinyl chloride paste resin; then add the plasticizer to the mixing kettle at a uniform flow rate, and during the addition of the plasticizer, continue stirring and monitor the temperature to maintain the temperature at 30°C. After the plasticizer is added, continue stirring for 5 minutes; finally, add the modified combined additive to the mixing kettle in equal amounts three times, with an interval of 2 minutes between each addition, and stir for 10 minutes after all are added to obtain a uniform mixture with good fluidity; Step 2: The mixture is transported to a dipping tank through a pipeline, and the pre-prepared glove mold is dipped into the mixture at a uniform and slow speed. The temperature of the mixture in the dipping tank is maintained at 20° C. by a constant temperature control system. The dipping time is 80 seconds to ensure that the surface of the mold is evenly covered with a layer of the mixture. Step 3: The impregnated glove blanks are transferred together with the mold to a plasticizing furnace for plasticizing treatment. The plasticizing furnace adopts segmented heating control. First, the glove blanks are kept in a low temperature section of 180°C for 3 minutes to initially plasticize and shape the glove blanks. Then, they are kept in a medium temperature section of 200°C for 3 minutes to further promote the plasticizing reaction of the material and the regularity of the arrangement of the molecular chains. Finally, they are kept in a high temperature section of 220°C for 4 minutes to ensure that the glove blanks are completely plasticized and all properties are stable. The entire plasticizing time is 10 minutes. Step 4: The plasticized gloves are transferred together with the mold to a cooling and demoulding device, and are first quickly cooled to 80°C by air cooling to preliminarily shape the gloves, and then demoulding is performed. The demoulding gloves are then trimmed, inspected, and other post-processing steps to remove excess parts and defective products on the edge of the gloves to obtain oil-resistant polyvinyl chloride gloves.

[0014] In the second embodiment, the present invention provides a technical solution: an oil-resistant polyvinyl chloride glove, composed of the following raw materials by weight: 110 parts of polyvinyl chloride paste resin, 40 parts of plasticizer, 6 parts of stabilizer, and 10 parts of combined additives; The preparation method of the combined additive comprises: The nano-silica was dried at 110°C for 3 hours to remove moisture; Add the dried nano-silica into a high-speed mixer and stir at 900 rpm for 7 minutes; Slowly adding the maleic anhydride grafted polyolefin elastomer into a high-speed mixer, and continuing to mix and stir with the nano-silicon dioxide for 13 minutes, with the mixing temperature controlled at 140° C., to obtain the combined additive; A preparation process of oil-resistant polyvinyl chloride gloves comprises the following steps: Step 1, after weighing the polyvinyl chloride paste resin, plasticizer, stabilizer, and modified combined additive by weight, first add the polyvinyl chloride paste resin into a closed mixing kettle with heating and stirring functions, turn on the stirring device, set the stirring speed to 300 rpm, and heat the mixing kettle at the same time to raise the temperature in the kettle to 30°C; then slowly add the stabilizer to the mixing kettle, and continue stirring for 3 minutes to ensure that the stabilizer is evenly dispersed in the polyvinyl chloride paste resin; then add the plasticizer to the mixing kettle at a uniform flow rate, and during the addition of the plasticizer, continue stirring and monitor the temperature to maintain the temperature at 30°C. After the plasticizer is added, continue stirring for 5 minutes; finally, add the modified combined additive to the mixing kettle in equal amounts three times, with an interval of 2 minutes between each addition, and stir for 10 minutes after all are added to obtain a uniform mixture with good fluidity; Step 2: The mixture is transported to a dipping tank through a pipeline, and the pre-prepared glove mold is dipped into the mixture at a uniform and slow speed. The temperature of the mixture in the dipping tank is maintained at 20° C. by a constant temperature control system. The dipping time is 80 seconds to ensure that the surface of the mold is evenly covered with a layer of the mixture. Step 3: The impregnated glove blanks are transferred together with the mold to a plasticizing furnace for plasticizing treatment. The plasticizing furnace adopts segmented heating control. First, the glove blanks are kept in a low temperature section of 180°C for 3 minutes to initially plasticize and shape the glove blanks. Then, they are kept in a medium temperature section of 200°C for 3 minutes to further promote the plasticizing reaction of the material and the regularity of the arrangement of the molecular chains. Finally, they are kept in a high temperature section of 220°C for 4 minutes to ensure that the glove blanks are completely plasticized and all properties are stable. The entire plasticizing time is 10 minutes. Step 4: The plasticized gloves are transferred together with the mold to a cooling and demoulding device, and are first quickly cooled to 80°C by air cooling to preliminarily shape the gloves, and then demoulding is performed. The demoulding gloves are then trimmed, inspected, and other post-processing steps to remove excess parts and defective products on the edge of the gloves to obtain oil-resistant polyvinyl chloride gloves.

[0015] In the third embodiment, the present invention provides a technical solution: an oil-resistant polyvinyl chloride glove, composed of the following raw materials by weight: 120 parts of polyvinyl chloride paste resin, 60 parts of plasticizer, 10 parts of stabilizer, and 15 parts of combined additives; The preparation method of the combined additive comprises: The nano-silica was dried at 110°C for 3 hours to remove moisture; Add the dried nano-silica into a high-speed mixer and stir at 900 rpm for 7 minutes; Slowly adding the maleic anhydride grafted polyolefin elastomer into a high-speed mixer, and continuing to mix and stir with the nano-silicon dioxide for 13 minutes, with the mixing temperature controlled at 140° C., to obtain the combined additive; A preparation process of oil-resistant polyvinyl chloride gloves comprises the following steps: Step 1, after weighing the polyvinyl chloride paste resin, plasticizer, stabilizer, and modified combined additive by weight, first add the polyvinyl chloride paste resin into a closed mixing kettle with heating and stirring functions, turn on the stirring device, set the stirring speed to 300 rpm, and heat the mixing kettle at the same time to raise the temperature in the kettle to 30°C; then slowly add the stabilizer to the mixing kettle, and continue stirring for 3 minutes to ensure that the stabilizer is evenly dispersed in the polyvinyl chloride paste resin; then add the plasticizer to the mixing kettle at a uniform flow rate, and during the addition of the plasticizer, continue stirring and monitor the temperature to maintain the temperature at 30°C. After the plasticizer is added, continue stirring for 5 minutes; finally, add the modified combined additive to the mixing kettle in equal amounts three times, with an interval of 2 minutes between each addition, and stir for 10 minutes after all are added to obtain a uniform mixture with good fluidity; Step 2: The mixture is transported to a dipping tank through a pipeline, and the pre-prepared glove mold is dipped into the mixture at a uniform and slow speed. The temperature of the mixture in the dipping tank is maintained at 20° C. by a constant temperature control system. The dipping time is 80 seconds to ensure that the surface of the mold is evenly covered with a layer of the mixture. Step 3: The impregnated glove blanks are transferred together with the mold to a plasticizing furnace for plasticizing treatment. The plasticizing furnace adopts segmented heating control. First, the glove blanks are kept in a low temperature section of 180°C for 3 minutes to initially plasticize and shape the glove blanks. Then, they are kept in a medium temperature section of 200°C for 3 minutes to further promote the plasticizing reaction of the material and the regularity of the arrangement of the molecular chains. Finally, they are kept in a high temperature section of 220°C for 4 minutes to ensure that the glove blanks are completely plasticized and all properties are stable. The entire plasticizing time is 10 minutes. Step 4: The plasticized gloves are transferred together with the mold to a cooling and demoulding device, and are first quickly cooled to 80°C by air cooling to preliminarily shape the gloves, and then demoulding is performed. The demoulding gloves are then trimmed, inspected, and other post-processing steps to remove excess parts and defective products on the edge of the gloves to obtain oil-resistant polyvinyl chloride gloves.

[0016] In the fourth embodiment, the present invention provides a technical solution: the combined additive in the first embodiment is replaced by a modified combined additive, and the other steps are the same as those in the first embodiment. The preparation method of the modified combined additive is as follows: The first step is to graft the surface of nano-silicon dioxide, disperse the nano-silicon dioxide in an organic solvent, add a silane coupling agent, stir and react at 70°C for 5 hours, filter, wash and dry after the reaction to obtain the surface-grafted nano-silicon dioxide; the silane coupling agent is vinyl triethoxysilane or γ-methacryloxypropyl trimethoxysilane; The second step is to synthesize the modified polyolefin elastomer, wherein the maleic anhydride grafted polyolefin elastomer and the small molecule compound containing an amino functional group are subjected to a grafting reaction in a solution in the presence of an initiator, the reaction temperature is 130° C., the reaction time is 4 hours, and after the reaction is completed, the solvent is removed to obtain the modified polyolefin elastomer; the small molecule compound containing an amino functional group is aminopropyltrimethoxysilane or N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane; The third step is to dry the surface-grafted nano-silica at 110°C for 3 hours to remove moisture; Step 4: Add the dried surface-grafted nano-silica into a high-speed mixer and stir at a speed of 900 rpm for 7 minutes; Step 5: slowly add the modified polyolefin elastomer into a high-speed mixer, and continue to mix and stir with the surface-grafted nano-silicon dioxide for 13 minutes, with the mixing temperature controlled at 140° C., to obtain the modified composite additive; In a fifth embodiment, the present invention provides a technical solution: the amount of the modifying additive in the fourth embodiment is replaced with 10 parts, and the other steps are the same as those in the fourth embodiment; In the sixth embodiment, the present invention provides a technical solution: the amount of the modifying additive in the fourth embodiment is replaced by 15 parts, and the other steps are the same as those in the fourth embodiment.

[0017] The elongation at break, tensile strength, oil resistance and solvent resistance of the gloves prepared in the above embodiments were measured by a Vickers microhardness tester and an electronic universal testing machine. After the measurement, it was found that the elongation at break, tensile strength, oil resistance and solvent resistance of the gloves prepared in the fifth embodiment all had better performance. Therefore, the content of the fifth embodiment is the optimal preparation process of polyvinyl chloride gloves.

[0018] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. An oil-resistant polyvinyl chloride glove, characterized in that: The invention is composed of the following raw materials by weight: 100-120 parts of polyvinyl chloride paste resin, 20-60 parts of plasticizer, 2-10 parts of stabilizer and 5-15 parts of combined additives; The preparation method of the combined additive comprises: The nano-silica was dried at 110°C for 3 hours to remove moisture; Add the dried nano-silica into a high-speed mixer and stir at 900 rpm for 7 minutes; The maleic anhydride grafted polyolefin elastomer was slowly added into a high-speed mixer, and was continuously mixed and stirred with the nano-silicon dioxide for 13 minutes, with the mixing temperature being controlled at 140° C., to obtain the composite additive.

2. The oil-resistant polyvinyl chloride glove according to claim 1, characterized in that: The plasticizer is one or more of dioctyl phthalate, dioctyl terephthalate and dioctyl adipate.

3. The oil-resistant polyvinyl chloride glove according to claim 1, characterized in that: The stabilizer is one or more of a calcium-zinc stabilizer, a barium-zinc stabilizer, and an organic tin stabilizer.

4. The oil-resistant polyvinyl chloride glove according to claim 1, characterized in that: The combined additive consists of nano silicon dioxide and modified polyolefin elastomer, and the modified polyolefin elastomer is maleic anhydride grafted polyolefin elastomer.

5. The oil-resistant polyvinyl chloride glove according to claim 1, characterized in that: The combination additive may also be replaced by a modified combination additive, and the preparation method of the modified combination additive includes: The first step is to graft the surface of nano-silicon dioxide; Step 2: Synthesis of modified polyolefin elastomer; The third step is to dry the surface-grafted nano-silicon dioxide to remove moisture; Step 4: Add the dried surface-grafted nano-silicon dioxide into a high-speed mixer; Step 5: slowly add the modified polyolefin elastomer into the high-speed mixer, and continue to mix and stir with the surface-grafted nano-silicon dioxide to obtain the modified composite additive.

6. A process for preparing oil-resistant polyvinyl chloride gloves, characterized in that: The steps include: Step 1: After weighing the polyvinyl chloride paste resin, plasticizer, stabilizer, and modified combination additive in parts by weight, first add the polyvinyl chloride paste resin into a closed mixing kettle with heating and stirring functions, turn on the stirring device, and heat the mixing kettle at the same time; Step 2: transport the mixture to a dipping tank through a pipeline, and dip the pre-prepared glove mold into the mixture at a uniform and slow speed; Step 3: The impregnated glove blanks together with the mold are transferred to a plasticizing furnace for plasticizing treatment. The plasticizing furnace adopts segmented heating control; Step 4: The plasticized gloves are transferred together with the mold to a cooling and demolding device for demolding. The demolded gloves are then trimmed, inspected and other post-processing steps to remove excess parts and defective products on the edge of the gloves to obtain oil-resistant polyvinyl chloride gloves.

7. The process for preparing oil-resistant polyvinyl chloride gloves according to claim 6, characterized in that: In the step 2, the temperature of the mixture in the dipping tank is maintained at 20-80° C. by a constant temperature control system.

8. The process for preparing oil-resistant polyvinyl chloride gloves according to claim 6, characterized in that: In step 4, the gloves are first cooled rapidly to 80-100° C. by air cooling to preliminarily shape the gloves, and then demoulding is performed.