A process for the production of medical surgical gloves using low ammonia latex

Abstract

The application relates to the technical field of latex gloves, and discloses an application process for producing medical surgical gloves by using low-ammonia latex, which comprises the following steps: S1, latex pre-vulcanization: performing pre-vulcanization treatment on low-ammonia concentrated natural latex; S2, mold pretreatment: performing cleaning, drying and preheating on the mold; S3, mold dipping: dipping the pre-vulcanized latex in the mold; and S4, vulcanization forming: performing post-treatment on the latex film after drying vulcanization, so that the finished gloves are obtained. The medical surgical gloves are prepared by sequentially performing the steps of latex pre-vulcanization, mold pretreatment, mold dipping and vulcanization forming; the medical surgical gloves have the advantages that the elastic deformation capacity is good, the gloves are convenient to wear; the tensile property is good, and the gloves are not prone to tearing; the aging resistance is good, the comprehensive performance is stable under long-time harsh environment; the puncture resistance is good, the gloves are not prone to being broken due to being cut by surgical equipment when being worn by doctors, the safety is high, and infection is avoided.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of latex gloves, in particular to an application process for producing medical surgical gloves by using low-ammonia latex. BACKGROUND

[0002] Medical surgical gloves can well protect the safety of users due to the barrier protection effect and have been widely applied to the production and life of people. Natural latex gloves are comfortable and soft in hand feeling, practical in wear and practical, and thus are widely loved by consumers. At present, high-NH3 (0.7%) concentrated latex is generally used as a production raw material in rubber glove production. However, the volatility and irritancy of ammonia have a bad influence on the production environment and seriously affect the physical and mental health of workers. Therefore, under the premise of not affecting the strength, elasticity, tensile property, aging resistance and other properties and processing technology of existing latex products such as medical gloves, the application of low-ammonia and ammonia-free natural latex in latex products is one of the key problems to be solved.

[0003] A manufacturing method of sulfur-free and nitrosamine-free latex gloves is disclosed in a Chinese patent (authorized publication number CN104097339A). The patent technology comprises a radiation vulcanized rubber emulsion preparation process, a model preparation process, an immersion coagulant process, an immersion latex process, an immersion separating agent process and a post-processing process. The natural rubber emulsion initial green strength selected in the radiation vulcanized rubber emulsion preparation process is at least 8 MPa. After radiation vulcanization by a low-energy electron accelerator or a gamma irradiation device, 0.5-2 parts of superfine silicon dioxide and 0.5-2 parts of zinc oxide are added according to the mass ratio of the obtained radiation vulcanized emulsion, and after stirring for 60 minutes, the mixture is sent to the immersion latex process tank for glove production. The method has the advantages of low cost, high mechanical strength of latex glove products and industrialized production. The prepared latex glove product is soft, sulfur-free, nitrosamine-free, non-toxic and convenient to wear, but the tensile strength and tear resistance of the produced gloves are not good, and the aging resistance is also not good. The comprehensive performance is not stable enough in a long time in a harsh environment. SUMMARY

[0004] The application aims to provide an application process for producing medical surgical gloves by using low-ammonia latex to solve the problems in the background technology.

[0005] To achieve the above-mentioned purpose, the application provides the following technical scheme.

[0006] An application process for producing medical surgical gloves by using low-ammonia latex comprises the following steps.

[0007] S1, latex pre-vulcanization: take 900-1100 parts by mass concentration of 60% low ammonia concentrated natural latex, and add 18-22 parts by mass concentration of 20% potassium hydroxide solution, 10-14 parts by mass concentration of 50% sulfur solution, 8-10 parts by mass concentration of 50% zinc oxide solution, 65-75 parts by mass concentration of 50% calcium carbonate solution, 9-11 parts of accelerator, 10-14 parts of antioxidant, 1.5-2.5 parts of surfactant and 18-22 parts by mass concentration of 60% natural silk glue, stir evenly; then the mixed latex is placed in a 54±1℃ water bath, slowly stirred, and the vulcanization degree of the latex is monitored, and the latex is taken out when the vulcanization degree of the latex reaches the end of the under-vulcanization stage and the beginning of the normal vulcanization stage; and after standing and settling for 48h, filter and reserve for use;

[0008] S2, mold pretreatment: clean the mold and preheat it in 85-95℃ hot water, dry it, immerse the coagulant, and dry it in an oven at 85-100℃ for standby;

[0009] S3, mold dipping: take out the pre-vulcanized latex in step S1, clean the surface skin, and stir evenly at 280-320r / min; immerse the latex in the mold at 25-30℃, take it out after 15-20s of immersion, dry it in 60-110℃ hot air, then apply a coating, and roll up the bottom of the glue film after standing for 1-1.5min;

[0010] S4, vulcanization forming: dry and vulcanize the glue film prepared in step S3 at 90-110℃ for 15-30min to form the surface of the glue film, then perform post-processing, and the finished glove is obtained.

[0011] As a further scheme of the application: the accelerator in step S1 is a zinc diethyldithiocarbamate solution with a mass concentration of 50%; the antioxidant is a 2,6-di-tert-butyl-p-cresol solution with a mass concentration of 50%; and the surfactant is a peregal O solution with a mass concentration of 10%.

[0012] As a further scheme of the application: the preparation method of the low ammonia concentrated natural latex in step S1 is as follows:

[0013] The raw latex is separated into concentrated latex with a dry glue mass fraction of 60% by centrifugal separation, a deproteinization treatment agent containing protease is added for protein decomposition, then filtered to remove the protein in the latex, and the low ammonia concentrated natural latex is obtained.

[0014] As a further scheme of the application: the coagulant in step S2 is one of hydrochloric acid with a mass fraction of 37%-38%, sodium silicofluoride solution with a mass fraction of 20%-25%, and polyvinyl methyl ether with a mass fraction of 40%-45%.

[0015] As a further scheme of the present application: the coating acrylate, polyurethane, polypropylene urethane, paraffin oil and silicone oil in the S3 step, the mass ratio is (55-65):(8-12):(18-22):(4-6):(4-6).

[0016] As a further scheme of the present application: the post-processing in the S4 step includes hot water vulcanization, hot water soaking and drying.

[0017] As a further scheme of the present application: the hot water vulcanization, hot water soaking and drying method is as follows:

[0018] After the surface of the adhesive film is shaped, the mold is immersed in 85-95℃ hot water for heating for 30s, and after being taken out, it is placed for drying for 3min, and the mold is placed in an oven for air blowing heating at 90℃ until it is completely dry, and after being taken out, it is demolded; the demolded glove is placed in 100-105℃ hot water for water bath vulcanization for 2h, and then is treated by sodium hypochlorite oxidation, and then is immersed in 75-85℃ hot water for soaking and cleaning, and then is dried, and the finished glove is prepared.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] The present application sequentially prepares the medical surgical glove through latex pre-vulcanization, mold pretreatment, mold dipping and vulcanization shaping; the medical surgical glove has good elastic deformation capacity, is convenient to wear, has good tensile property and is not prone to tearing; has good aging resistance, stable comprehensive performance in long time harsh environment; has good puncture resistance, is not prone to rupture due to being cut by surgical equipment when worn by a doctor, has high safety and avoids infection. Embodiment Example

[0021] In the embodiment of the present application, an application process for producing a medical surgical glove using low ammonia latex includes the following steps:

[0022] S1, latex pre-vulcanization: 900 parts of low ammonia concentrated natural latex with a mass concentration of 60% and removed protein are taken, and 18 parts of a potassium hydroxide solution with a mass concentration of 20%, 10 parts of a sulfur solution with a mass concentration of 50%, 8 parts of a zinc oxide solution with a mass concentration of 50%, 65 parts of a calcium carbonate solution with a mass concentration of 50%, 9 parts of a zinc diethyl dithiocarbamate solution with a mass concentration of 50%, 10 parts of a 2,6-di-tert-butyl-p-cresol solution with a mass concentration of 50%, 1.5 parts of a peregal O solution with a mass concentration of 10% and 18 parts of natural silk glue with a mass concentration of 60% are added, and stirring is uniform; then the mixed latex is placed in a 53℃ water bath, slowly stirred, and the vulcanization degree of the latex is monitored, and the latex is taken out when the vulcanization degree of the latex reaches the end of the under-vulcanization stage and the beginning of the normal-vulcanization stage; and after being placed and settled for 48h, the latex is filtered for standby use;

[0023] S2, mold pretreatment: clean the mold, and preheat in 85℃ hot water, dry, then immerse in hydrochloric acid with mass fraction of 37%-38%, and dry in oven at 85℃ for standby;

[0024] S3, mold dipping: take out the pre-vulcanized latex in step S1, clean the surface skin, and stir uniformly at 280r / min; immerse the latex in the mold at 25℃, take out after 15s of immersion, dry in 60℃ hot air, then apply a coating layer composed of acrylate, polyurethane, polypropylene urethane, paraffin oil and silicone oil with mass ratio of 55:8:18:4:4, and roll up the bottom of the latex film after 1min of standing;

[0025] S4, vulcanization forming: dry and vulcanize the latex film prepared in step S3 at 90℃ for 15min, after the surface of the latex film is formed, immerse the mold in 85℃ hot water for heating for 30s, take out and stand for drying for 3min, place the mold in the oven and heat to complete dryness by blowing air at 90℃, take out and demold; after demolding, place the glove in 100℃ hot water for water bath vulcanization for 2h, then oxidize by sodium hypochlorite, immerse in 75℃ hot water for cleaning, then dry, and obtain the finished glove. Embodiment

[0026] In the embodiment of the application, an application process for producing medical surgical gloves using low ammonia latex includes the following steps:

[0027] S1, latex pre-vulcanization: take 1000 parts of low ammonia concentrated natural latex with mass concentration of 60% and remove protein, and add 20 parts of potassium hydroxide solution with mass concentration of 20%, 12 parts of sulfur solution with mass concentration of 50%, 9 parts of zinc oxide solution with mass concentration of 50%, 70 parts of calcium carbonate solution with mass concentration of 50%, 10 parts of zinc diethyl dithiocarbamate solution with mass concentration of 50%, 2 parts of peregal O solution with mass concentration of 10%, and 20 parts of natural silk glue with mass concentration of 60%, and stir uniformly; then place the mixed latex in a 54℃ water bath, slowly stir, and monitor the vulcanization degree of the latex, take out the latex when the vulcanization degree of the latex reaches the end of the under-vulcanization stage and the beginning of the normal-vulcanization stage; and stand for 48h after filtration for standby;

[0028] S2, mold pretreatment: clean the mold, and preheat in 90℃ hot water, dry, then immerse in sodium silicofluoride solution with mass fraction of 20%-25%, and dry in oven at 95℃ for standby;

[0029] S3, mold dipping: take out the pre-vulcanized latex in S1 step, clean the surface skin, and stir uniformly at 300 r / min; dip the latex in the mold at 28℃, take out after 18s, dry in 80℃ hot air, then coat with a coating layer composed of acrylate, polyurethane, polypropylene urethane, paraffin oil and silicone oil in a mass ratio of 12:2:4:1:1, and roll up the bottom of the film after 1.2min;

[0030] S4, vulcanization forming: dry and vulcanize the film prepared in S3 step at 100℃ for 25min, after the surface of the film is formed, immerse the mold in 90℃ hot water for heating for 30s, take out and dry for 3min, place the mold in an oven and heat to complete dryness at 90℃ with air blowing, take out and demold; after demolding, place the glove in 102℃ hot water for water bath vulcanization for 2h, then oxidize with sodium hypochlorite, immerse in 80℃ hot water for cleaning, then dry, and obtain the finished glove. Embodiment

[0031] In the embodiment of the application, an application process for producing medical surgical gloves using low ammonia latex includes the following steps:

[0032] S1, latex pre-vulcanization: take 1100 parts by mass of low ammonia concentrated natural latex with a mass concentration of 60% and remove the protein, and add 22 parts by mass of a potassium hydroxide solution with a mass concentration of 20%, 14 parts by mass of a sulfur solution with a mass concentration of 50%, 10 parts by mass of a zinc oxide solution with a mass concentration of 50%, 75 parts by mass of a calcium carbonate solution with a mass concentration of 50%, 11 parts by mass of a zinc diethyl dithiocarbamate solution with a mass concentration of 50%, 14 parts by mass of a 2,6-di-tert-butyl-p-cresol solution with a mass concentration of 50%, 2.5 parts by mass of a peregal O solution with a mass concentration of 10%, and 22 parts by mass of natural silk glue with a mass concentration of 60%, and stir uniformly; then place the mixed latex in a 55℃ water bath, stir slowly, and monitor the vulcanization degree of the latex, take out the latex when the vulcanization degree of the latex reaches the end of the under-vulcanization stage and the beginning of the normal-vulcanization stage; and after standing and settling for 48h, filter and reserve for use;

[0033] S2, mold pretreatment: clean the mold, preheat in 95℃ hot water, dry, and then immerse in polyvinyl methyl ether with a mass fraction of 40%-45%, and dry in an oven at 100℃ for standby;

[0034] S3, mold dipping: take out the pre-vulcanized latex in S1 step, clean the surface skin, and stir uniformly at 320 r / min; dip the latex in the mold at 30℃, take out after 20s, dry in 110℃ hot air, then coat with a coating layer composed of acrylate, polyurethane, polypropylene urethane, paraffin oil and silicone oil in a mass ratio of 65:12:22:6:6, and roll up the bottom of the film after 1.5min;

[0035] S4, vulcanization molding: dry vulcanize the film prepared in step S3 at 110℃ for 30min, after the surface of the film is shaped, immerse the mold in hot water at 95℃ for heating for 30s, take it out and stand for drying for 3min, place the mold in an oven and blow heat at 90℃ until completely dry, take it out and demold; immerse the demolded glove in hot water at 105℃ for water bath vulcanization for 2h, then treat with sodium hypochlorite oxidation, immerse in hot water at 85℃ for washing, then dry, and obtain the finished glove.

[0036] In order to better illustrate the technical effects of the present application, the following experiments are described:

[0037] The glove prepared by the method for manufacturing a latex glove without sulfur and nitrosamine disclosed by the patent network (publication number: CN104097339A, publication date: October 15, 2014) is used as Comparative Example 1, and the glove prepared by the method for manufacturing a safety dipped glove disclosed by the patent network (publication number: CN109864373A, publication date: June 11, 2019) is used as Comparative Example 2.

[0038] Take the glove samples prepared in Example 1, Example 2, Example 2, Comparative Example 1 and Comparative Example 2, the glove samples are medium gloves, the average double-layer thickness is 0.28mm, and the performance indicators of the gloves before and after accelerated aging are tested, including: puncture resistance test, tensile property test and tensile stress test.

[0039] The accelerated aging test should be carried out according to the method specified in ISO188: the sample is cut from the glove after accelerated aging at (70±2)℃×(168±2)h.

[0040] I. Puncture resistance test:

[0041] The puncture resistance test is carried out according to the provisions of ISO 374-1; the glove sample is fixed on the bottle opening, and the conical probe is moved downward at a speed of 100mm / min to penetrate the sample, the peak load of the punctured glove is calculated, and the puncture strength of each test piece is recorded, and the puncture strength (unit: N) of Example 1, Example 2, Example 2, Comparative Example 1 and Comparative Example 2 is obtained, respectively.

[0042] II. Tensile property test:

[0043] The tensile property test was carried out according to ISO 37, and a type 2 dumbbell-shaped cutting tool was used to cut test pieces from the palm of each glove; the test pieces of Example 1, Example 2, Example 2, Comparative Example 1 and Comparative Example 2 were placed on the clamps of the tensile testing machine, and the tensile property test was carried out; the tensile strength and elongation at break of each test piece were recorded, and the tensile strength (unit: MPa) and elongation at break (unit: 100%) of Example 1, Example 2, Example 2, Comparative Example 1 and Comparative Example 2 were obtained, respectively;

[0044] III. Constant-stress test:

[0045] The 300% constant-stress test was carried out according to ISO 37, and a type 2 dumbbell-shaped cutting tool was used to cut test pieces from the palm of each glove; the test pieces of Example 1, Example 2, Example 2, Comparative Example 1 and Comparative Example 2 were placed on the tensile testing machine, and the tensile property test was carried out; the stress required when the elongation of the sample was 300% (unit: MPa) was recorded.

[0046] The results obtained from the puncture resistance test, tensile property test and constant-stress test were recorded in Table 1 below;

[0047] Table 1, Puncture Resistance, Tensile and Constant-Stress Test Table

[0048] From Table 1, it can be seen that the puncture strength, tensile strength, elongation at break and 300% constant-stress of Example 1, Example 2, Example 2 are all greater than those of Comparative Example 1 and Comparative Example 2, both before and after the accelerated aging test; and the change in puncture strength, tensile strength and elongation at break of Example 1, Example 2, Example 2 before and after the accelerated aging test is less than that of Comparative Example 1 and Comparative Example 2, and meets the requirements of GB / T 7543-2020 "Disposable Sterilized Rubber Surgical Gloves";

[0049] It can be concluded that the medical surgical gloves prepared by the present application have good elastic deformation ability, are easy to wear; have good tensile properties and are not prone to tearing; have good aging resistance and stable comprehensive performance when worn for a long time; have good puncture resistance, and doctors are not prone to rupture when wearing due to the cutting of surgical equipment, have high safety and avoid infection.

[0050] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can make equivalent substitutions or changes within the technical scope disclosed by the present application according to the technical solution and inventive concept of the present application, which should be covered within the protection scope of the present application.

Claims

1. An application process for producing medical surgical gloves using low-ammonia latex, characterized in that: The following steps are involved: S1. Latex pre-vulcanization: 900-1100 parts by mass of 60% low-ammonia concentrated natural rubber latex are added thereto, 18-22 parts by mass of 20% potassium hydroxide solution, 10-14 parts by mass of 50% sulfur solution, 8-10 parts by mass of 50% zinc oxide solution, 65-75 parts by mass of 50% calcium carbonate solution, 9-11 parts by mass of accelerator, 10-14 parts by mass of antioxidant, 1.5-2.5 parts by mass of surfactant, and 18-22 parts by mass of 60% natural sericin, and stirred evenly; the mixed latex is then placed in a 54±1°C water bath, stirred slowly, and the vulcanization degree of the latex is monitored. When the vulcanization degree of the latex reaches the end of the under-vulcanization stage and the beginning of the normal vulcanization stage, the latex is removed; the latex is allowed to settle for 48 hours, and then filtered for use; S2. Mold pretreatment: clean the mold, preheat it in hot water at 85-95°C, dry it, soak it in a coagulant, and dry it in an oven at 85-100°C for later use; S3, mold dipping: Take out the pre-vulcanized latex in step S1, clean the surface skin, and stir it evenly at 300r / min; dip the latex into the mold at 25-30°C for 15-20s, take it out, dry it in hot air at 60-110°C, then apply the coating, let it stand for 1-1.5 minutes, and then curl the bottom edge of the film; S4. Vulcanization molding: The film prepared in step S3 is dried and vulcanized at 90-110°C for 15-30 minutes until the film surface is formed, and then post-processed to obtain the finished gloves.

2. The process for producing medical surgical gloves using low-ammonia latex according to claim 1, characterized in that: In step S1, the accelerator is a zinc diethyldithiocarbamate solution with a mass concentration of 50%; the antioxidant is a 2,6-di-tert-butyl-p-cresol solution with a mass concentration of 50%; and the surfactant is a peregal O solution with a mass concentration of 10%.

3. The process for producing medical surgical gloves using low-ammonia latex according to claim 1, characterized in that: The preparation method of the low-ammonia concentrated natural rubber latex in step S1 is as follows: The raw latex is separated into concentrated latex with a dry rubber mass fraction of 60% by centrifugal separation, and then a deproteinizing agent containing protease is added to decompose the protein; then the latex is filtered to remove the protein to obtain low-ammonia concentrated natural latex.

4. The process for producing medical surgical gloves using low-ammonia latex according to claim 1, characterized in that: In the step S2, the coagulant is one of 37% to 38% by mass of hydrochloric acid, 20% to 25% by mass of sodium silicofluoride solution, and 40% to 45% by mass of polyvinyl methyl ether.

5. The process for producing medical surgical gloves using low-ammonia latex according to claim 1, characterized in that: The coating in step S3 is composed of acrylate, polyurethane, polyacrylamide, paraffin oil and silicone oil, and the mass ratio thereof is (55-65): (8-12): (18-22): (4-6): (4-6).

6. The process for producing medical surgical gloves using low-ammonia latex according to claim 1, characterized in that: The post-treatment in step S4 includes hot water vulcanization, hot water soaking and drying.

7. The process for producing medical surgical gloves using low-ammonia latex according to claim 6, characterized in that: The method of hot water vulcanization, hot water soaking and drying is as follows: After the film surface is formed, the mold is immersed in 85-95°C hot water and heated for 30 seconds. After being taken out, it is left to dry for 3 minutes. The mold is placed in an oven and heated with air at 90°C until completely dry. After being taken out, it is demoulded. The demoulded gloves are placed in 100-105°C hot water for water bath vulcanization for 2 hours, then oxidized with sodium hypochlorite, and then immersed in 75-85°C hot water for soaking and washing, and then dried to produce finished gloves.