Method of producing natural latex rubber condom

Abstract

The present application relates to the technical field of condom production, in particular to a natural latex rubber condom production method; S1: all used raw materials are inspected, and raw latex is prepared and its performance is tested, and the qualified product of raw latex is obtained after testing; S2: solution preparation; S3: preparation of vulcanized latex; S4: vulcanized latex ripening, storage and filtration; S5: sent to a condom linkage machine production line; after mold washing treatment is completed, latex dipping treatment is entered, after the latex dipping treatment is completed, demolding is performed to obtain a semi-finished product; after the condom demolding is completed, a finished product post-treatment process is entered; after the semi-finished product bubble isolation agent is completed, a final drying process is entered; after drying, a condom finished product is obtained. The process method can effectively ensure the uniformity of dipping and the forming effect in the production process of the condom, ensure the toughness and overall tensile strength of the obtained condom product, and improve the use performance of the product.

Description

Technical Field

[0001] This invention relates to the field of condom manufacturing technology, and in particular to a method for producing natural latex rubber condoms. Background Technology

[0002] Condoms are circular, thin-film products with the opening edge rolled into a ring. The film is transparent and elastic, used for male contraception, and also prevents the transmission of sexually transmitted diseases (during intercourse). The main requirement for the product is that the effective part of the film is waterproof, and it can be made into various types such as roughened, irregularly shaped, and colored films.

[0003] Currently, condoms are mainly made from natural rubber or polyurethane. Current improvements to condoms primarily focus on enhancing comfort, such as reducing the reject rate through improvements to the rubber formula or reducing the thickness through mold improvements to enhance sensory stimulation.

[0004] After comparing similar products on the market, our company found that some existing condom manufacturing processes also exist. For example, patent document CN109223292A discloses a method for producing sterilized condoms. Its main steps include condom sterilization: bare condoms from the forming line are transferred to a Class 100,000 cleanroom for electrical testing and inner packaging to control the initial contamination count, followed by sterilization. Condoms packaged using this method are then sterilized using ethylene oxide, gamma ray irradiation, high-energy electron beam or X-ray, moist heat sterilization, and low-temperature plasma sterilization. The sterilization steps are described as follows: ethylene oxide... Ethane gaseous disinfectant sterilization: The ethylene oxide sterilization chamber utilizes steam for heating, heat preservation, and humidification, and is a sealed space with negative pressure. Completely packaged condoms are placed according to the chamber's capacity requirements, and the chamber's inlet door is closed. The condoms are preheated within the sterilization chamber… During sterilization, a 58% hydrogen peroxide solution is ionized at low temperatures, inactivating various microorganisms on the medical devices, thus achieving sterilization. The single-pot sterilization dosage is 2ml, injected via a needle-prick capsule inhalation method. The sterilization temperature is maintained at 40-50℃, and the sterilization cycle is 50 minutes, meeting the standard requirement of a sterilization assurance level of 10⁻³.

[0005] In summary, the existing technologies described above mainly optimize and improve the sterilization process when producing condoms. However, the overall production of condoms still uses the existing processes. As a result, the condoms produced using the existing processes have poor shaping effects and are easily damaged during demolding. Overall, the performance of the condoms produced is relatively insufficient.

[0006] Therefore, this invention addresses the problems existing in the existing condom production process and proposes a new method for producing natural latex rubber condoms that can improve the quality of condom products, thereby better solving the problems existing in the prior art. Summary of the Invention

[0007] To solve one of the aforementioned technical problems, the present invention provides a method for producing natural latex rubber condoms, comprising the following steps:

[0008] S1: Inspect all raw materials used, prepare raw latex and test its properties. After testing, qualified raw latex is obtained.

[0009] First, inspect all raw materials used, identifying the product packaging markings, model number, weight, and place of origin. Then, open the packaging and verify that the appearance of the raw materials conforms to the technical requirements before weighing and using them. After use, keep accurate records of the preparation process.

[0010] S2: Solution preparation:

[0011] Prepare stabilizer solutions, dispersant solutions, and complexing agent dispersions as needed;

[0012] The stabilizer used is a 10% casein solution, and the dispersant used is a 10% NF solution.

[0013] Stabilizers and dispersants are mainly used here to improve the stability of latex and facilitate the dispersion of various compounding agents during grinding; the compounding agent dispersion can enhance the physical and mechanical properties of rubber and improve its antioxidant and anti-aging properties.

[0014] S3: Preparation of vulcanized latex:

[0015] Check if the mechanical equipment is working properly, remove the rubber from the vulcanizing tank, close the valve, and press the material to the pre-marked scale. Two people must be present during the pressing process to prevent rubber from leaking out.

[0016] Add tap water to the hot water tank and heat it to 50℃-65℃. Turn on the agitator of the vulcanizing tank, add an appropriate amount of soft water, and add stabilizer casein, NF, and ammonia water to the vulcanizing tank. Turn on the circulating hot water valve and hot water circulation pump and start heating to 43℃-55℃. Then add various dispersions in sequence, requiring accurate weighing and verification. Add them slowly while stirring. The order of addition is: sulfur, accelerator, antioxidant, zinc oxide.

[0017] S4: Vulcanized latex maturation, storage, and filtration;

[0018] S5: Feed into the condom production line;

[0019] Install the impregnation tank mixer, clean the filter screen and add it to the tank, start the mixer, scrape off the rubber, lumps, and debris, flush the rubber inlet pipe to ensure it is unobstructed, adjust the rubber temperature and rubber level, and maintain the relative humidity of the impregnation chamber at ≥30%;

[0020] Once the temperature of each part meets the process requirements, raise the impregnation tank to start production. The glue temperature must reach above 25℃, and the impregnation length should be adjusted in time.

[0021] Mold cleaning treatment: The mold is first cleaned with tap water, and then soaked in soft water at 65-75℃ or above. The requirements for the preparation of soft water are: conductivity ≤40.

[0022] After the mold washing process is completed, the latex impregnation process begins. The impregnation involves impregnating both sides and then curling the edges. A film drying process is carried out in conjunction with each impregnation.

[0023] The impregnation environment needs to be measured daily, and adjustments should be made promptly if it fails to meet the requirements. The glue temperature should be maintained at 28-35℃, and the impregnation environment in the impregnation chamber (reference item) should be tested at 30-42℃; steam pressure: ≥0.50MPa; impregnation speed (180-220) pieces / min; impregnation height: (210+5) mm for the first pass, and about 5 mm shorter for the second pass. The specific impregnation height of the produced products shall be determined by the workshop to ensure that the products reach the specified length; among which, the requirements for the impregnation glue are: in the first impregnation, the total solids content is 43-50%, the chloroform value is 3-4%, and in the second impregnation, the total solids content is 43-50%, the chloroform value is 3-4%, and the total alkalinity (%) is 0.4-0.6.

[0024] During impregnation, keep the adhesive flowing and the adhesive surface clean. Remove any air bubbles, impurities, oil stains, etc., and ensure that the adhesive tube is kept unobstructed, the flow rate is appropriate, and a certain adhesive level is maintained.

[0025] The specific drying process for the adhesive film is as follows: one pass of hot air: 160-180℃; two passes of hot air: 160-180℃; one pass of drying: 80-100℃; two passes of drying: 80-110℃; drying after edge rolling: 40-70℃.

[0026] After the latex impregnation process is completed, the product is demolded to obtain a semi-finished product;

[0027] After the condom is demolded, it enters the post-processing technology of this finished product;

[0028] The semi-finished product obtained from the above demolding process is treated with a foam release agent;

[0029] The integrated vulcanizing machine is used for soaking and washing treatment; the processing capacity is one batch for every 40 minutes of production on the continuous machine; the processing time is 30-50 minutes; the initial preparation method of the release agent is as follows: the release agent water in the release agent tank is prepared once a week. For the first preparation, add the release agent and water according to formula 1, and turn on the agitator to disperse the release agent evenly; the release agent composition formula includes 30kg of white carbon and the remainder of water, totaling 1000kg; during normal production, 15-20kg of release agent and an appropriate amount of water are added to the release agent tank each shift. Each time the product is produced, the release agent is added to the integrated vulcanizing machine according to the formula requirements. The amount of release agent water pumped into the vulcanizing machine each time is about 1 / 2-2 / 3 of the drum volume. 100-150g of emulsified silicone oil is added to the release agent each time the product is produced.

[0030] Each shift must drain 1 / 4 of the water in the preparation tank and replenish it with tap water to 1000 kg before use. Add 5 kg of white carbon black.

[0031] After the semi-finished foam release agent is completed, it is sent to the final drying process;

[0032] After drying, the condoms are sent to the packaging process for packaging to obtain the finished condoms.

[0033] After the integrated vulcanizing machine is turned on, it rotates at (8-12) rpm to remove excess moisture from the product (about 2-5 minutes).

[0034] Turn on the blower (hot air) to dry the product. During the drying process, the speed will be increased (but not more than 36 rpm).

[0035] Drying temperature: 75℃-110℃; time: 40-60 minutes.

[0036] During the drying process, the products inside the drying chamber must not be piled up or clump together;

[0037] Regularly check the changes in drying temperature to prevent the product from being over-sulfurized or under-sulfurized;

[0038] After drying, shake the product to below 50℃, remove the product from the shaker, and place it in the designated product basket, ensuring that the product does not touch the ground.

[0039] Fill out labels, weigh the products, then send them for pre-inspection, and finally send them to the raw materials room to be neatly stacked.

[0040] If edge cracks occur, the speed of the post-vulcanizing machine should be relatively slowed down during the soaking and final drying processes;

[0041] During the transfer process after the demolding process, the products must not touch the ground, and the loading container must be clean.

[0042] In any of the above solutions, it is preferred that during demolding, the temperature of the alkaline water bath is 40℃-50℃, the concentration of the alkaline water is ≤1.0%, and the immersion height in the alkaline water should reach the edge of the film.

[0043] When raising the tank, the cationic soap in the anti-stick tank should first be prepared into a 1.0-1.5% solution. During normal production, 300-500ml of 30% cationic soap solution should be added every hour.

[0044] The concentration of positive soap in the stripping tank is 0.1%-0.3%;

[0045] If excessive bubbles appear in the stripping tank, add 50g-100g of silicone oil per hour to quickly remove the bubbles.

[0046] In any of the above schemes, the preferred method is that the preparation process of the 10% casein solution includes the following steps: (1) Weigh the casein and moisten it with soft water for more than four hours to expand it, observe that it is fully dissolved and there are no large particles; (2) Add ammonia and borax and stir until completely dissolved; (3) The ammonia should be used according to the actual concentration; (4) Cover the prepared solution and wait for use; The weight ratio of each component of the above 10% casein solution is as follows: 7 parts casein, 3 parts 15% ammonia, and 90 parts soft water.

[0047] In any of the above schemes, the preferred method for preparing the 10% NF solution includes the following steps: accurately weighing NF, dissolving it in soft water, stirring intermittently until completely dissolved, stirring evenly and filtering before use; the weight ratio of each component of the above 10% NF solution is as follows: NF 12.38 parts, soft water 100 parts.

[0048] In any of the above schemes, the preferred method is that during the curing, storage, and filtration of vulcanized latex, the latex should be stored for more than 72 hours, filtered with a screen filter, and centrifuged at 15,000 rpm in a high-speed tubular centrifuge to remove residues. After processing, the latex should continue to be stored for more than 6 hours, filtered again with a 200-mesh stainless steel mesh, placed in the glue-adding tank of the machine, and conditioning agents should be added to adjust the total solids. Samples should be taken for rapid testing to meet the requirements of the condom process formula. The latex should be stored for more than 8 hours before use, and if the ammonia content is lower than the target, it should be adjusted in time. In addition, it is required to be delivered to the glue-adding tank of the machine 8 hours before use.

[0049] In any of the above schemes, it is preferred that when preparing vulcanized latex for heat treatment, the time is ≤5 hours, and the water temperature during the heat treatment process shall not exceed 65℃. The vulcanization process is continuously stirred, the total solids content of the vulcanized rubber is controlled at (45±5)%, and the chloroform value of the vulcanized rubber is controlled at the initial to final stage.

[0050] Measure its chloroform value, and release the material when it meets the requirements. After releasing the material, check whether the valves of each storage tank are closed and secured. After the material is released, rinse the vulcanizing tank and the release pipe with a small amount of soft water.

[0051] During the heat treatment and vulcanization process, carefully observe the temperature changes and the condition of the rubber compound, and wait for the process to be completed.

[0052] After the above processing is completed, turn off the water, electricity and heating valves, seal the rubber material with plastic sheeting, turn on the circulating cooling water if necessary, hang the vulcanization card, and clean up.

[0053] After centrifugation, samples are taken for testing, and the results should meet the requirements of the quality control specifications for the condom production process.

[0054] In any of the above schemes, it is preferred that the compounding agent dispersion mainly includes 50% sulfur dispersion, 40% accelerator PX, 40% ZDC dispersion, 50% zinc oxide dispersion, and 264 mixed dispersion.

[0055] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0056] 1. This process involves two dipping processes in the production of condoms, which effectively ensures the uniformity of the dipping and the molding effect, guarantees the toughness and overall tensile strength of the resulting condom product, and improves the product's performance.

[0057] 2. In this invention, the method of conveying and drying the condom in a horizontal state during the impregnation and edge rolling process, combined with the method of fixed-axis rotation and edge rolling in a horizontal state and then drying, can ensure the uniform shaping effect of the product. This changes the problem of uneven condom wall thickness caused by the downward accumulation of adhesive due to the vertical drying and edge rolling in the traditional form.

[0058] 3. The addition of stabilizers, dispersant solutions, compounding agent dispersions, and anti-sticking agents can ensure product quality and achieve smooth demolding, avoiding damage to the condom products during demolding and improving demolding effect and efficiency. Attached Figure Description

[0059] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or components are generally identified by similar reference numerals. In the drawings, the elements or components are not necessarily drawn to scale.

[0060] Figure 1 This is a schematic diagram of the production process of the present invention. Detailed Implementation

[0061] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore merely examples and should not be used to limit the scope of protection of the present invention. The specific structure of the present invention is as follows: Figure 1 As shown in the image.

[0062] Example: A method for producing natural latex rubber condoms, comprising the following steps:

[0063] S1: Inspect all raw materials used, prepare raw latex and test its properties. After testing, qualified raw latex is obtained.

[0064] First, inspect all raw materials used, identifying the product packaging markings, model number, weight, and place of origin. Then, open the packaging and verify that the appearance of the raw materials conforms to the technical requirements before weighing and using them. After use, keep accurate records of the preparation process.

[0065] S2: Solution preparation:

[0066] Prepare stabilizer solutions, dispersant solutions, and complexing agent dispersions as needed;

[0067] The stabilizer used is a 10% casein solution, and the dispersant used is a 10% NF solution.

[0068] Stabilizers and dispersants are mainly used here to improve the stability of latex and facilitate the dispersion of various compounding agents during grinding; the compounding agent dispersion can enhance the physical and mechanical properties of rubber and improve its antioxidant and anti-aging properties.

[0069] S3: Preparation of vulcanized latex:

[0070] Check if the mechanical equipment is working properly, remove the rubber from the vulcanizing tank, close the valve, and press the material to the pre-marked scale. Two people must be present during the pressing process to prevent rubber from leaking out.

[0071] Add tap water to the hot water tank and heat it to 50℃-65℃. Turn on the agitator of the vulcanizing tank, add an appropriate amount of soft water, and add stabilizer casein, NF, and ammonia water to the vulcanizing tank. Turn on the circulating hot water valve and hot water circulation pump and start heating to 43℃-55℃. Then add various dispersions in sequence, requiring accurate weighing and verification. Add them slowly while stirring. The order of addition is: sulfur, accelerator, antioxidant, zinc oxide.

[0072] S4: Vulcanized latex maturation, storage, and filtration;

[0073] S5: Feed into the condom production line;

[0074] Install the impregnation tank mixer, clean the filter screen and add it to the tank, start the mixer, scrape off the rubber, lumps, and debris, flush the rubber inlet pipe to ensure it is unobstructed, adjust the rubber temperature and rubber level, and maintain the relative humidity of the impregnation chamber at ≥30%;

[0075] Once the temperature of each part meets the process requirements, raise the impregnation tank to start production. The glue temperature must reach above 25℃, and the impregnation length should be adjusted in time.

[0076] Mold cleaning treatment: The mold is first cleaned with tap water, and then soaked in soft water at 65-75℃ or above. The requirements for the preparation of soft water are: conductivity ≤40.

[0077] After the mold washing process is completed, the latex impregnation process begins. The impregnation involves impregnating both sides and then curling the edges. A film drying process is carried out in conjunction with each impregnation.

[0078] Among them, the method of keeping the condom in a horizontal position during the impregnation and edge rolling process, and then rolling the edge while maintaining the horizontal position and then drying it, can ensure the uniform shaping effect of the product.

[0079] The impregnation environment needs to be measured daily, and adjustments should be made promptly if it fails to meet the requirements. The glue temperature should be maintained at 28-35℃, and the impregnation environment in the impregnation chamber (reference item) should be tested at 30-42℃; steam pressure: ≥0.50MPa; impregnation speed (180-220) pieces / min; impregnation height: (210+5) mm for the first pass, and about 5 mm shorter for the second pass. The specific impregnation height of the produced products shall be determined by the workshop to ensure that the products reach the specified length; among which, the requirements for the impregnation glue are: in the first impregnation, the total solids content is 43-50%, the chloroform value is 3-4%, and in the second impregnation, the total solids content is 43-50%, the chloroform value is 3-4%, and the total alkalinity (%) is 0.4-0.6.

[0080] During impregnation, keep the adhesive flowing and the adhesive surface clean. Remove any air bubbles, impurities, oil stains, etc., and ensure that the adhesive tube is kept unobstructed, the flow rate is appropriate, and a certain adhesive level is maintained.

[0081] The specific drying process for the adhesive film is as follows: one pass of hot air: 160-180℃; two passes of hot air: 160-180℃; one pass of drying: 80-100℃; two passes of drying: 80-110℃; drying after edge rolling: 40-70℃.

[0082] After the latex impregnation process is completed, the product is demolded to obtain a semi-finished product;

[0083] After the condom is demolded, it enters the post-processing technology of this finished product;

[0084] The semi-finished product obtained from the above demolding process is treated with a foam release agent;

[0085] The integrated vulcanizing machine is used for soaking and washing treatment; the processing capacity is one batch for every 40 minutes of production on the continuous machine; the processing time is 30-50 minutes; the initial preparation method of the release agent is as follows: the release agent water in the release agent tank is prepared once a week. For the first preparation, add the release agent and water according to formula 1, and turn on the agitator to disperse the release agent evenly; the release agent composition formula includes 30kg of white carbon and the remainder of water, totaling 1000kg; during normal production, 15-20kg of release agent and an appropriate amount of water are added to the release agent tank each shift. Each time the product is produced, the release agent is added to the integrated vulcanizing machine according to the formula requirements. The amount of release agent water pumped into the vulcanizing machine each time is about 1 / 2-2 / 3 of the drum volume. 100-150g of emulsified silicone oil is added to the release agent each time the product is produced.

[0086] Each shift must drain 1 / 4 of the water in the preparation tank and replenish it with tap water to 1000 kg before use. Add 5 kg of white carbon black.

[0087] After the semi-finished product is foamed with the release agent, it is sent to the final drying process; after drying, the condoms are sent to the packaging process to obtain the finished condoms.

[0088] After the integrated vulcanizing machine is turned on, it rotates at (8-12) rpm to remove excess moisture from the product (about 2-5 minutes).

[0089] Turn on the blower (hot air) to dry the product. During the drying process, the speed will be increased (but not more than 36 rpm).

[0090] Drying temperature: 75℃-110℃; time: 40-60 minutes.

[0091] During the drying process, the products inside the drying chamber must not be piled up or clump together;

[0092] Regularly check the changes in drying temperature to prevent the product from being over-sulfurized or under-sulfurized;

[0093] After drying, shake the product to below 50℃, remove the product from the shaker, and place it in the designated product basket, ensuring that the product does not touch the ground.

[0094] Fill out labels, weigh the products, then send them for pre-inspection, and finally send them to the raw materials room to be neatly stacked.

[0095] If edge cracks occur, the speed of the post-vulcanizing machine should be relatively slowed down during the soaking and final drying processes;

[0096] During the transfer process after the demolding process, the products must not touch the ground, and the loading container must be clean.

[0097] In any of the above solutions, it is preferred that during demolding, the temperature of the alkaline water bath is 40℃-50℃, the concentration of the alkaline water is ≤1.0%, and the immersion height in the alkaline water should reach the edge of the film.

[0098] When raising the tank, the cationic soap in the anti-stick tank should first be prepared into a 1.0-1.5% solution. During normal production, 300-500ml of 30% cationic soap solution should be added every hour.

[0099] The concentration of positive soap in the stripping tank is 0.1%-0.3%;

[0100] If excessive bubbles appear in the stripping tank, add 50g-100g of silicone oil per hour to quickly remove the bubbles.

[0101] In any of the above schemes, the preferred method is that the preparation process of the 10% casein solution includes the following steps: (1) Weigh the casein and moisten it with soft water for more than four hours to expand it, observe that it is fully dissolved and there are no large particles; (2) Add ammonia and borax and stir until completely dissolved; (3) The ammonia should be used according to the actual concentration; (4) Cover the prepared solution and wait for use; The weight ratio of each component of the above 10% casein solution is as follows: 7 parts casein, 3 parts 15% ammonia, and 90 parts soft water.

[0102] In any of the above schemes, the preferred method for preparing the 10% NF solution includes the following steps: accurately weighing NF, dissolving it in soft water, stirring intermittently until completely dissolved, stirring evenly and filtering before use; the weight ratio of each component of the above 10% NF solution is as follows: NF 12.38 parts, soft water 100 parts.

[0103] In any of the above schemes, the preferred method is that during the curing, storage, and filtration of vulcanized latex, the latex should be stored for more than 72 hours, filtered with a screen filter, and centrifuged at 15,000 rpm in a high-speed tubular centrifuge to remove residues. After processing, the latex should continue to be stored for more than 6 hours, filtered again with a 200-mesh stainless steel mesh, placed in the glue-adding tank of the machine, and conditioning agents should be added to adjust the total solids. Samples should be taken for rapid testing to meet the requirements of the condom process formula. The latex should be stored for more than 8 hours before use, and if the ammonia content is lower than the target, it should be adjusted in time. In addition, it is required to be delivered to the glue-adding tank of the machine 8 hours before use.

[0104] In any of the above schemes, it is preferred that when preparing vulcanized latex for heat treatment, the time is ≤5 hours, and the water temperature during the heat treatment process shall not exceed 65℃. The vulcanization process is continuously stirred, the total solids content of the vulcanized rubber is controlled at (45±5)%, and the chloroform value of the vulcanized rubber is controlled at the initial to final stage.

[0105] Measure its chloroform value, and release the material when it meets the requirements. After releasing the material, check whether the valves of each storage tank are closed and secured. After the material is released, rinse the vulcanizing tank and the release pipe with a small amount of soft water.

[0106] During the heat treatment and vulcanization process, carefully observe the temperature changes and the condition of the rubber compound, and wait for the process to be completed.

[0107] After the above processing is completed, turn off the water, electricity and heating valves, seal the rubber with plastic sheeting, turn on the circulating cooling water if necessary, hang the vulcanization card, and clean up.

[0108] After centrifugation, samples are taken for testing, and the results should meet the requirements of the quality control specifications for the condom production process.

[0109] In any of the above schemes, it is preferred that the compounding agent dispersion mainly includes 50% sulfur dispersion, 40% accelerator PX, 40% ZDC dispersion, 50% zinc oxide dispersion, and 264 mixed dispersion.

[0110] In any of the above schemes, the preferred method is that the preparation process of 50% sulfur dispersion includes the following steps: sand mill volume 250dm3, fine bead particle size 2-5mm, dosage 100kg; grinding time: ≥6 hours; records: usage records should be kept.

[0111] The weight proportions of the components of the above 50% sulfur dispersion are as follows: 50 parts sulfur, 10 parts 10% casein, 20 parts 10% NF, and 20 parts soft water.

[0112] In any of the above schemes, the preferred method is that the preparation process of 40% accelerator PX includes the following steps: the volume of the sand mill is 250dm3, the particle size of the fine beads is 2-5mm, and the dosage is 100kg; the grinding time is ≥6 hours; the inspection items are: no odor or abnormal thickening in appearance, and no control items are required; the records are: the usage records should be kept.

[0113] The weight proportions of the components of the above-mentioned 40% accelerator PX are as follows: 40 parts PX, 20 parts 10% casein, 10 parts 10% NF, and 30 parts soft water.

[0114] In any of the above schemes, the preferred method is that the preparation process of 40% ZDC dispersion includes the following steps: the volume of the sand mill is 250 dm3, the particle size of the fine beads is 2-5 mm, and the dosage is 100 kg; the grinding time is more than 6 hours; the inspection items are: no odor or abnormal thickening phenomenon in appearance, which is not a control item; the records are: the usage records should be kept.

[0115] The weight proportions of the components of the above 40% ZDC dispersion are as follows: 4 parts ZDC, 10 parts 10% casein, 10 parts 10% NF, and 30 parts soft water.

[0116] In any of the above schemes, the preferred method is that the preparation process of 50% zinc oxide dispersion includes the following steps: sand mill volume 250dm3, fine bead particle size 2-5mm, dosage 100kg; grinding time: ≥6 hours; inspection items: no odor or abnormal thickening in appearance, no control items; records: usage records should be kept.

[0117] The weight proportions of the components of the above 50% zinc oxide dispersion are as follows: 50 parts zinc oxide, 20 parts 10% casein, 10 parts 10% NF, and 20 parts soft water.

[0118] In any of the above schemes, the preferred method is that the 264 mixed dispersion preparation process includes the following steps: a sand mill with a volume of 250 dm3, fine beads with a particle size of 2-5 mm, and a dosage of 100 kg; grinding time: ≥6 hours; inspection items: no odor or abnormal thickening in appearance, no control items; records: usage records should be kept.

[0119] In any of the above embodiments, it is preferred that the particle size and sedimentation amount of the sulfur and zinc oxide dispersions in the condom compounding agent dispersion effectively ensure the uniformity of film formation. The sulfur dispersion used in the condom has a particle size controlled below 2 μm (95%), a particle size distribution center of 0.7 μm (average level), and a sedimentation amount controlled at 30 mg / cm²·h. The zinc oxide dispersion has a particle size controlled below 0.8 μm (95%), a particle size distribution center of 0.4 μm (average level), and a sedimentation amount controlled at 30 mg / cm²·h.

[0120] This invention also includes an anti-sticking release agent, which is prepared by mixing and dissolving 20 kg of room temperature soft water with 30 kg of 50% cationic soap until completely dissolved. Using the anti-sticking release agent effectively prevents rubber from sticking together, facilitates product demolding, and improves processing performance.

[0121] This process employs a two-stage dipping process in condom production, effectively ensuring uniformity and molding effect, guaranteeing the toughness and overall tensile strength of the resulting condom, and improving product performance. The use of double drying followed by edge rolling during dipping and edge rolling ensures proper product shaping. The addition of stabilizers, dispersant solutions, compounding agent dispersions, and anti-sticking agents guarantees product quality and ensures smooth demolding, preventing damage to the condom during demolding and improving demolding efficiency and effectiveness.

[0122] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. For those skilled in the art, any alternative improvements or transformations made to the implementation of the present invention fall within the protection scope of the present invention.

[0123] Any aspects of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A method for producing natural latex rubber condoms, characterized in that, Includes the following steps: S1. Inspect all raw materials used, prepare raw latex and test its properties. After testing, obtain qualified raw latex. S2, Solution preparation; S3. Preparation of vulcanized latex: Check if the mechanical equipment is normal, peel off the rubber from the vulcanizing tank, close the valve, and press the material to the pre-calibrated scale. Two people must be present during pressing to prevent the latex from leaking. Add tap water to the hot water tank and heat it to 50℃-65℃. Turn on the vulcanizing tank agitator, add an appropriate amount of soft water, and add the stabilizer casein, NF, and ammonia to the vulcanizing tank. Turn on the circulating hot water valve and hot water circulation pump, and start heating to 43℃-55℃. Then add various dispersions in sequence, requiring accurate weighing and verification. Add them slowly while stirring. The order of addition is: sulfur, accelerator, antioxidant, zinc oxide. S4. Vulcanized latex maturation, storage, and filtration; S5. Feed the condom into the production line; install the impregnation tank mixer, clean the filter screen and add it to the tank, start the mixer, scrape off the rubber, lumps, and debris, flush the glue supply pipe to ensure it is unobstructed, adjust the glue temperature and glue level, and maintain the relative humidity of the impregnation chamber at ≥30%; after the temperature of each part meets the process requirements, raise the impregnation tank to start production. The glue temperature must reach above 25℃, and adjust the impregnation length in time; mold washing treatment: the mold is first washed with tap water, and then washed and soaked in soft water at 65℃-75℃ or above. The requirements for the preparation of soft water are: conductivity ≤40; after the mold washing treatment, it enters the latex impregnation treatment. The impregnation adopts double-sided impregnation and edge rolling treatment. The film drying process is carried out in conjunction with each impregnation; after the latex impregnation treatment, the condom is demolded to obtain a semi-finished product; after the condom is demolded, it enters the semi-finished product post-processing process; the semi-finished product obtained from the above demolding is soaked in a release agent; after the semi-finished product is soaked in the release agent, it is sent to the final drying process; the dried condom is sent to the packaging process for packaging to obtain the finished condom. The specific drying process for the adhesive film is as follows: one pass of hot air at 160℃-180℃; two passes of hot air at 160℃-180℃; one pass of drying at 80℃-100℃; two passes of drying at 80℃-110℃; drying after edge rolling at 40℃-70℃. The method of keeping the condom in a horizontal position during the dipping and rolling process, and drying in combination with fixed-axis rotation rolling in a horizontal position and then drying again, can ensure the uniform shaping effect of the product. This changes the problem of uneven condom wall thickness caused by the downward accumulation of adhesive due to the traditional method of drying and rolling in a vertical position. The impregnation environment needs to be measured daily, and adjustments should be made promptly if it fails to meet the requirements. The glue temperature should be maintained at 28℃~35℃, and the impregnation environment test temperature in the impregnation chamber should be 30℃~42℃; the steam pressure should be ≥0.50MPa; the impregnation speed should be 180~220 pieces / min; the impregnation height: 210±5mm for the first pass, and 5mm shorter for the second pass. The specific impregnation height for each product should be determined by the workshop to ensure that the product reaches the specified length; the requirements for the impregnation compound are: for the first impregnation, the total solids content should be 43%-50%, the chloroform value should be at least 3-4, and the total alkalinity should be 0.4%-0.6%.

2. The method for producing natural latex rubber condoms according to claim 1, characterized in that: When demolding, the temperature of the alkali bath should be 40℃-50℃, the alkali concentration should be ≤1.0%, and the immersion height in alkali water should be up to the edge of the film. When raising the tank, the cationic soap in the anti-stick tank should first be prepared into a 1.0%-1.5% solution. During normal production, 300ml-500ml of 30% cationic soap solution should be added every hour. The concentration of positively charged soap in the demolding tank is 0.1%-0.3%; If excessive bubbles appear in the demolding tank, add 50g-100g of silicone oil per hour to quickly remove the bubbles.

3. The method for producing natural latex rubber condoms according to claim 2, characterized in that, The preparation process of 10% casein solution includes the following steps: (1) Weigh casein and moisten it with soft water for more than four hours to see if it is fully dissolved and without large particles; (2) Add ammonia and borax and stir until completely dissolved; (3) Ammonia should be used according to the actual concentration; (4) Cover the prepared solution and wait for use; The weight ratio of each component of the above 10% casein solution is as follows: 7 parts casein, 3 parts 15% ammonia, and 90 parts soft water.

4. The method for producing natural latex rubber condoms according to claim 3, characterized in that: The preparation process of 10% NF solution includes the following steps: accurately weigh NF, dissolve it in soft water, stir intermittently until completely dissolved, stir evenly and filter before use; the weight ratio of each component of the above 10% NF solution is as follows: NF 12.38 parts, soft water 100 parts.

5. The method for producing natural latex rubber condoms according to claim 4, characterized in that: During the curing, storage, and filtration of vulcanized latex, the rubber compound should be stored for at least 72 hours, filtered through a screen filter, and centrifuged at 15,000 rpm in a high-speed tubular centrifuge to remove residue. After processing, the latex should be stored for at least 6 more hours, filtered again through a 200-mesh stainless steel mesh, placed in the machine's rubber-adding tank, and adjusted with additives to regulate the total solids. Samples should be taken for rapid testing to ensure the latex meets the requirements of the condom manufacturing process. The latex should be stored for at least 8 hours before use. If the ammonia content is lower than the target, it should be adjusted promptly. Furthermore, the latex must be delivered to the machine's rubber-adding tank 8 hours before use.

6. The method for producing natural latex rubber condoms according to claim 5, characterized in that: When preparing vulcanized latex for heat treatment, the time should be ≤5 hours, and the water temperature during the heat treatment process should not exceed 65℃; the vulcanization process should be continuously stirred, the total solids content of the vulcanized rubber should be controlled at 45±5%, and the chloroform value of the vulcanized rubber should be controlled at the initial to final stage. Measure its chloroform value, and release the material when it meets the requirements. After releasing the material, check whether the valves of each storage tank are closed and secured. After the material is released from the discharge pipe, rinse the vulcanizing tank and the discharge pipe with a small amount of soft water. During the heat treatment and vulcanization process, carefully observe the temperature changes and the condition of the rubber compound, and wait for the process to be completed. After the above processing is completed, turn off the water, electricity and heating valves, seal the rubber with plastic sheeting, turn on the circulating cooling water if necessary, hang the vulcanization card, and clean up. After centrifugation, samples are taken for testing, and the results should meet the requirements of the quality control specifications for the condom production process.

7. The method for producing natural latex rubber condoms according to claim 6, characterized in that: The compounding agent dispersion mainly includes 50% sulfur dispersion, 40% accelerator PX, 40% ZDC dispersion, 50% zinc oxide dispersion, and 264 mixed dispersion.

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