Leather lining sealing agent with low atomization value and formaldehyde removal function and preparation method of leather lining sealing agent

Abstract

The invention provides a low-fogging-value formaldehyde-removing leather lining sealing agent and a preparation method thereof. The lining sealing agent comprises 30-60 parts of a water-based resin emulsion; 30 to 60 parts of water; 5-15 parts of an organosilicon hand feeling auxiliary agent; 2-8 parts of a wax emulsion; 5 to 15 parts of an aldehyde removal material; 1-3 parts of a wetting leveling agent; 0.5 to 2 parts of a thickening agent; and 0.1 to 0.5 part of an anti-settling auxiliary agent. The water-based resin emulsion with low odor is mainly adopted, so that the overall odor of the sealing agent is low, a conventional casein component is removed, and the atomization value is low. Meanwhile, the formaldehyde removal material can effectively reduce the content of formaldehyde and acetaldehyde, so that the overall VOC is low, and the interior sealing performance is high mainly through the water-based resin emulsion with high adhesive force and other materials. The leather lining sealing agent disclosed by the invention is excellent in performance and suitable for being used in airtight spaces such as automobile seats and the like.

Description

Technical Field

[0001] The invention belongs to the field of leather sealing agents, and in particular relates to a leather sealing agent with low atomization value and formaldehyde removal and a preparation method thereof. Background Art

[0002] In the process of leather product preparation, raw hides generally go through the preparation, tanning and retanning stages in sequence, and then enter the finishing stage. One step in the finishing process is to treat the fuzz on the back of the leather, also known as lining (back sealing); through lining treatment, the fuzz on the back of the leather can be sealed to prevent the fuzz and leather scraps from falling off and contaminating the coating during the finishing process. The lining effect can also make the leather fiber fuzz arranged in an orderly manner, which is conducive to subsequent bonding and other processing steps.

[0003] At present, most leather sealants on the market are mainly composed of casein, acrylic resin and modified silicone oil. However, most leather sealants on the market have problems such as strong odor and high volatile organic compounds (VOC). The strong odor is mainly caused by acrylic resin, and the high VOC is mainly reflected in the excessive volatile substances such as formaldehyde, which has an adverse effect on production, processing and application.

[0004] There are some leather finishing agents with low VOC content in the prior art. For example, a Chinese patent document with publication number CN 114181592A discloses a water-based leather finishing agent, which includes component A and component B. Component A includes a bisphenol A epoxy resin water-based emulsion, and component B includes a water-based plasticizer emulsion containing a plasticizer and castor oil. The leather finishing agent is made by compounding and mixing a water-based epoxy resin and a water-based plasticizer. It is mainly used before spraying an anti-sticking layer on the leather surface during the embossing process to improve the leather gloss. It is a water-based product, so it reduces the irritating odor caused by the volatilization of organic solvents during use. However, the performance of the above-mentioned leather finishing agent for lining treatment is general, and the fluff in the lining is difficult to fall down in an orderly manner. Summary of the invention

[0005] In view of the above problems, the present invention provides a leather sealing agent with low fogging value and formaldehyde removal and a preparation method thereof. The leather sealing agent of the present invention has excellent sealing performance and lower VOC, and is suitable for use in enclosed space products such as car seats.

[0006] The present invention provides a leather sealing agent with low fogging value and formaldehyde removal, comprising the following raw materials in parts by weight:

[0007] 30-60 parts of water-based resin emulsion;

[0008] 30-60 parts water;

[0009] 5-15 parts of silicone feel additives;

[0010] 2-8 parts of wax emulsion;

[0011] 5-15 parts of formaldehyde removal materials;

[0012] 1-3 parts of wetting and leveling agent;

[0013] 0.5-2 parts of thickener;

[0014] 0.1-0.5 parts of anti-settling agent;

[0015] The water-based resin emulsion is one or more of water-based polyurethane emulsion, water-based acrylic emulsion, silicone-modified polyurethane emulsion and silicone-modified acrylic emulsion; the formaldehyde-removing material is one or more of nano-photocatalyst titanium dioxide water dispersion, negative ion aqueous solution and tea polyphenol powder.

[0016] In an embodiment of the present invention, the aqueous resin emulsion has low odor and a solid content of 15-40%.

[0017] In an embodiment of the present invention, the silicone hand feel additive is one or more of isomeric methyl silicone oil emulsion, amino silicone oil emulsion and polyether siloxane copolymer; the wax emulsion is paraffin emulsion and / or oxidized polyethylene wax emulsion.

[0018] In an embodiment of the present invention, the wetting and leveling agent is an anionic surfactant and / or a nonionic surfactant; the thickener is one or more of polyacrylate, associative polyurethane thickener and hydroxyethyl cellulose.

[0019] In an embodiment of the present invention, the anti-settling aid is one or more of sepiolite, bentonite and montmorillonite.

[0020] In an embodiment of the present invention, the leather sealing agent further comprises 0.1-2 parts of a pH regulator and / or 0.1-1 parts of an antibacterial preservative.

[0021] In an embodiment of the present invention, the antibacterial preservative is benzisothiazolinone and / or 2-methyl-4-isothiazolin-3-one; the pH regulator is 2-amino-2-methyl-1-propanol and / or sodium hydroxide aqueous solution.

[0022] The present invention provides a method for preparing the leather sealing agent as described above, comprising the following steps:

[0023] The aqueous resin emulsion and water are mixed according to weight parts, and then silicone feel additives, wax emulsion, formaldehyde removal materials, wetting and leveling agents, optional antibacterial and antiseptic additives and pH adjusters are added in sequence under stirring conditions, and finally thickeners and anti-settling additives are added, and the material is filtered to obtain the leather sealing agent.

[0024] In an embodiment of the present invention, the stirring speed is 100 to 300 rpm / min; the mixing and stirring temperature is 15 to 35°C;

[0025] The stirring speed for adding the thickener and the anti-settling aid is 300-700 rpm / min, the stirring time is 30-90 min, and the viscosity is 500-2000 mPa.s.

[0026] The present invention provides application of the leather lining agent as mentioned above in the treatment of seat leather lining.

[0027] Currently, most of the sealing agents on the market have high VOCs, such as formaldehyde and acetaldehyde content exceeding the standard, which is difficult to meet the requirements of car seats (VOC≤100ppm); and they have a strong odor, and some of the irritating odors are mainly the smell of acrylic acid monomers and some solvents. These commercially available products have poor adhesion and average sealing performance.

[0028] Compared with the prior art, the present invention provides a leather sealing agent with low odor and formaldehyde removal, which uses a specific water-based resin emulsion as the main resin component, water as the solvent, and adds some formaldehyde-removing materials, silicone feel additives, wax emulsions and other raw material components. The present invention mainly uses a water-based resin emulsion with low odor, so that the overall odor of the sealing agent is low, and the conventional casein component is removed, and the atomization value is low. At the same time, the formaldehyde-removing material in the present invention can effectively reduce the content of formaldehyde and acetaldehyde, so that the overall VOC is low, and the strong sealing performance is mainly achieved by the water-based resin emulsion with strong adhesion and other materials. The leather sealing agent described in the present invention has excellent performance and is suitable for use in closed spaces such as car seats. DETAILED DESCRIPTION

[0029] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the technical scheme of the present invention is now described in detail below in conjunction with specific embodiments. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0030] The first object of the present invention is to provide a leather sealing agent with low fogging value and formaldehyde removal, comprising the following raw materials in parts by weight:

[0031] 30-60 parts of water-based resin emulsion;

[0032] 30-60 parts water;

[0033] 5-15 parts of silicone feel additives;

[0034] 2-8 parts of wax emulsion;

[0035] 5-15 parts of formaldehyde removal materials;

[0036] 1-3 parts of wetting and leveling agent;

[0037] 0.5-2 parts of thickener;

[0038] 0.1-0.5 parts of anti-settling agent;

[0039] The water-based resin emulsion is one or more of water-based polyurethane emulsion, water-based acrylic emulsion, silicone-modified polyurethane emulsion and silicone-modified acrylic emulsion; the formaldehyde-removing material is one or more of nano-photocatalyst titanium dioxide water dispersion, negative ion aqueous solution and tea polyphenol powder.

[0040] The leather sealing agent provided by the present invention has excellent sealing performance, lower VOC and low atomization value, and is suitable for application in closed space products such as car seats.

[0041] The leather sealing agent described in the embodiment of the present invention includes the following preparation raw materials: aqueous resin emulsion, water (usually deionized water), silicone feel additives, wax emulsion, formaldehyde removal materials, wetting and leveling agents, antibacterial and preservative additives, pH adjusters, thickeners and anti-settling additives.

[0042] In an embodiment of the present invention, the raw materials for preparing the leather sealing agent are: in parts by weight, 30-60 parts of aqueous resin emulsion, 30-60 parts of water, 5-15 parts of silicone feel additives, 2-8 parts of wax emulsion, 5-15 parts of formaldehyde-removing materials, 1-3 parts of wetting and leveling agents, 0-1 parts of antibacterial and preservative additives, 0-2 parts of pH adjusters, 0.5-2 parts of thickeners, and 0.1-0.5 parts of anti-settling additives.

[0043] Wherein, the aqueous resin emulsion is one or more of aqueous polyurethane emulsion, aqueous acrylic emulsion, organosilicon-modified polyurethane emulsion and organosilicon-modified acrylic emulsion, preferably aqueous polyurethane emulsion and aqueous acrylic emulsion; its weight parts can be 30 parts, 35 parts, 50 parts, 60 parts, etc. The aqueous resin emulsion is a carrier resin, which is used in the sealing agent to play the role of film-forming bonding, etc., and can make scattered leather fibers gather into bundles microscopically, while fixing other effective ingredients and providing film-forming, improving physical properties and other functions. The aqueous resin emulsion of the embodiment of the present invention is a commercially available product with a solid content of 15-40%. It is preferred to use the low-odor aqueous resin emulsion product produced by Sichuan Dawei Co., Ltd., which is conducive to reducing odor. The polyurethane and acrylic acid in the aqueous resin emulsion of the preferred embodiment of the present invention have a strong bonding effect, which can fix the leather back fluff and is not easy to stain.

[0044] Specifically, the solid content of the aqueous polyurethane emulsion can be 15-18%, and the polyurethane has low odor and good anti-stickiness, which can improve the sealing performance to a certain extent, such as the NU 2580 model product produced by Sichuan Dawe Co., Ltd. The solid content of the aqueous acrylic emulsion can be 30-40%, and it has a trace of acrylic monomer odor, good sealing performance, and can reduce the overall odor when combined with other resins, such as the RA 1210 model product produced by Sichuan Dawe Co., Ltd. The organosilicon-modified polyurethane emulsion has 80% silicon monomer content (the proportion of Si-C bonds on the molecule reaches about 80%), and the total solid content can be 30%; it feels comfortable, has certain sealing performance, and has low odor. The organosilicon-modified acrylic emulsion has 50% silicon monomer content, and the total solid content can be 40%; it has good wear resistance, smooth feel, and low odor.

[0045] The leather sealing agent component preferably includes 5-12 parts of silicone feel additives, such as 6 parts, 10 parts, 11 parts, etc.; it preferably includes one or more of isomeric methyl silicone oil emulsion, amino silicone oil emulsion and polyether siloxane copolymer, all of which can be corresponding commercial products. In addition, the sealing agent preferably includes 3-7 parts of wax emulsion, further 4-6 parts; the wax emulsion is preferably one or two of paraffin emulsion and oxidized polyethylene wax emulsion. The silicone feel additives described in the embodiments of the present invention have the characteristics of dense, soft, smooth and moisturizing feel. They and wax emulsions provide a certain moisturizing and delicate feel, and can also improve wear resistance and other properties.

[0046] Specifically, the isomeric methyl silicone oil emulsion, amino silicone oil emulsion and polyether siloxane copolymer are respectively the F8255, F8257 and F8291 products produced by Sichuan Dawe Co., Ltd. The paraffin wax emulsion is generally emulsified by 52# refined paraffin wax and non-ionic emulsifier, and has a smooth feel. The oxidized polyethylene wax emulsion is emulsified by high melting point oxidized polyethylene wax and anionic and non-ionic emulsifiers, and has a comfortable feel. The two can be the 5059 and 5178 products produced by Sichuan Dawe Co., Ltd. (the melting point of the paraffin wax in the paraffin wax emulsion can be 50-60°C, the melting point of the high melting point oxidized polyethylene wax is between 120-130°C, and the viscosity is 500-1000mPas (62#, 6r, Brookfield viscometer test)). The embodiment of the present invention can give the leather a moisturizing and comfortable feel by compounding wax emulsion and silicone feel additives, making it comfortable and natural to touch.

[0047] The leather sealing agent of the embodiment of the present invention comprises 5-15 parts of formaldehyde-removing materials, such as 5 parts, 6 parts, 8 parts, 10 parts, 15 parts, etc. The formaldehyde-removing materials are one or more of nano-photocatalyst titanium dioxide (TiO2) water dispersion, negative ion aqueous solution and tea polyphenol powder, preferably a composite of two. The formaldehyde-removing materials can reduce the release of VOCs in the component system of the present invention, remove formaldehyde and acetaldehyde on leather, and reduce irritating odors.

[0048] Wherein, the nano-photocatalyst TiO2 aqueous dispersion contains titanium dioxide, which can electronically transition under light conditions, react with aldehyde substances, and reduce VOC, but is easy to settle, and needs to add anti-settling aids to maintain stability; the particle size of titanium dioxide in the nano-titanium dioxide aqueous dispersion is 10-100nm, and the mass concentration is between 1-5%, and the material products produced by Hangzhou Jikang New Materials Co., Ltd. can be used. The negative ion aqueous solution is the product of water-soluble formaldehyde-removing substances (such as high-purity ethylene urea) and water dispersion, and the mass concentration is between 10-20%. The pH of the negative ion aqueous solution is about 7, which is a neutral solution with good compatibility, high formaldehyde removal efficiency, and can reduce odor. It can be a product produced by Shijiazhuang Zhouting Mineral Products Co., Ltd. and others. The tea polyphenol powder is mainly tea polyphenol components, which can react with formaldehyde to reduce VOC volatilization, and can be a product produced by Shanghai Guchen Biological Co., Ltd. and others; the particle size of the tea polyphenol powder is between 100-200nm.

[0049] In the embodiments of the present invention, the formaldehyde-removing materials have a strong formaldehyde-removing effect, which can significantly reduce the overall formaldehyde and acetaldehyde release of leather, reduce VOC while ensuring the performance of the sealing agent. In addition, the preferred formaldehyde-removing materials in the present invention have a certain synergistic effect when used in combination, which is better than the formaldehyde-removing effect of using a single one.

[0050] In addition, the leather sealing agent described in the specific embodiment of the present invention includes, by weight: 1-3 parts of a wetting and leveling agent, 0.1-1 parts of an antibacterial and preservative aid, 0.1-2 parts of a pH adjuster, 0.5-2 parts of a thickener, and 0.1-0.5 parts of an anti-settling aid.

[0051] The wetting and leveling agent mainly provides wetting performance for the substrate, and can be one or both of anionic surfactants and nonionic surfactants. The embodiments of the present invention can use corresponding commercially available wetting and leveling agent products, such as silicone or non-silicone products of BASF.

[0052] The antibacterial and preservative additive mainly serves to impart antibacterial and anti-corruption functions to the material as a whole, and is preferably 0.2-1 parts, more preferably 0.5-0.9 parts; the antibacterial and preservative additive is preferably one or both of benzisothiazolinone and 2-methyl-4-isothiazoline-3-one.

[0053] The pH adjuster is usually used to adjust the pH value to facilitate subsequent thickening and stabilization; preferably, 0.5-2 parts of the pH adjuster are included, and more preferably 0.6-1.8 parts. The pH adjuster is preferably one or both of 2-amino-2-methyl-1-propanol and sodium hydroxide aqueous solution, and commercially available products can be used.

[0054] The thickener described in the embodiment of the present invention is preferably one or more of polyacrylate, associative polyurethane thickener and hydroxyethyl cellulose, and commercially available products can be used, such as polyacrylate products provided by Dow, associative polyurethane thickener products provided by Wanhua, and hydroxyethyl cellulose products provided by Shandong Yutian Chemical Co., Ltd.; its weight parts can be 0.5 parts, 0.6 parts, 1.1 parts, 1.5 parts, 1.7 parts, etc. Specifically, the pH value of the polyacrylate thickener is 2-3, and the room temperature viscosity is less than 500mPas; the main components of the associative polyurethane thickener are hydrophobically modified polyurethane, diethylene glycol butyl ether and water, and the room temperature viscosity is between 20000-30000. Hydroxyethyl cellulose is generally solid and soluble in water, making it gel-like.

[0055] The anti-settling aid is preferably one or more of sepiolite, bentonite and montmorillonite, and more preferably a combination of two of them, such as the raw material components provided by Changan Renheng Company. The anti-settling aid is mainly a gray or white powder, which can be dispersed in water and has a particle size between 100-500nm. The thickener and the anti-settling aid work together to prevent the material components from stratifying and precipitating and becoming unstable.

[0056] Accordingly, the second object of the embodiment of the present invention is to provide a method for preparing the leather sealing agent as described above, comprising the following steps:

[0057] The aqueous resin emulsion and water are mixed according to weight parts, and then silicone feel additives, wax emulsion, formaldehyde removal materials, wetting and leveling agents, optional antibacterial and antiseptic additives and pH adjusters are added in sequence under stirring conditions, and finally thickeners and anti-settling additives are added, and the material is filtered to obtain the leather sealing agent.

[0058] Some embodiments of the present invention specifically include the following steps:

[0059] 1. Accurately weigh various raw materials and set them aside; clean the dispersing equipment, add component A-resin aqueous emulsion and component B-water (deionized water) into the dispersing kettle, the temperature condition is preferably one of 15°C, 25°C, and 35°C, the speed can be one of 100, 200, and 300 rpm / min, and the stirring time is one of 20, 30, and 40 min.

[0060] 2. Add component C-silicone feel additive, component D-wax emulsion (wax dispersion), component E-formaldehyde removal material, component F-wetting and leveling agent, and component G-antibacterial and antiseptic additive to the dispersion equipment in sequence (stir for 20 minutes after adding each component, and then add the next component). The temperature condition can be one of 15°C, 25°C, and 35°C, the rotation speed can be one of 100, 200, and 300 rpm / min, and the stirring time can be one of 20, 30, and 40 min.

[0061] 3. Add component H-pH regulator, maintain the speed, stir evenly, and test the pH. The pH range is preferably in the range of 7-8 or 8-9. The temperature condition is preferably one of 15°C, 25°C, and 35°C. The speed can be one of 100, 200, and 300 rpm / min, and the stirring time is one of 20, 30, and 40 min.

[0062] 4. Add component I-thickener and component J-anti-settling aid (stir for 20 minutes after each component is added, and then add the next component), increase the speed, stir evenly, and test the viscosity with a Brookfield viscometer. The viscosity range can be one of 500-1000, 1000-1500, 1000-2000mPa.s (preferably 1000-1500mPa.s), the temperature condition is one of 15°C, 25°C, and 35°C, the speed is preferably one of 300, 500, and 700rpm / min, and the stirring time can be one of 30, 50, and 80min. The viscosity, pH, and speed in the preparation process of the embodiment of the present invention have a great influence on the performance of the product. Under appropriate process conditions, qualified finishing agent products can be efficiently prepared. If the pH is too low, the thickening effect is poor, the viscosity is insufficient, and it is easy to delaminate; if the speed is too fast, it is easy to cause too many bubbles in the product, affecting the appearance and performance.

[0063] 5. Take samples, determine the solid content (solid content is between 20-25%) and appearance. After the sampling test meets the standards, filter the material. The filter screen is one of 120 mesh, 200 mesh, and 300 mesh.

[0064] 6. After passing the inspection, the products are filled, packaged and put into storage.

[0065] The leather sealing agent prepared in the embodiment of the present invention can effectively reduce VOC (mainly formaldehyde, acetaldehyde) and odor, and has very good hand feel and sealing performance. The sealing agent material components used in the embodiment of the present invention have low odors and do not have the irritating odor of products sold on the market. In addition, the leather sealing agent has a low atomization value and is suitable for use in car seats without affecting driving.

[0066] The embodiment of the present invention also provides the application of the leather sealing agent as described above in the treatment of seat leather sealing; the leather sealing agent can be called a leather auto seat sealing agent, etc., and is applied to the leather finishing process, which can effectively reduce VOC, odor and atomization value. It not only does not release VOC, but also can reduce the emission of formaldehyde and acetaldehyde in the leather itself.

[0067] In the embodiment of the present invention, the leather sealing agent formula contains nano-photocatalyst TiO2 water dispersion, negative ion aqueous solution, tea polyphenol powder and other components. After being sprayed on the suede surface of the leather back, it can absorb aldehydes or react with aldehydes to reduce the release of VOCs such as formaldehyde and acetaldehyde, and play a role in reducing odor and being environmentally friendly. At the same time, it has very good hand feel and sealing performance, low atomization value, and is conducive to application.

[0068] In order to further understand the present invention, the present invention is described in detail below in conjunction with the examples, and the protection scope of the present invention is not limited by the following examples. In the examples, each raw reagent and material can be obtained commercially, as shown below; the experimental methods without specifying specific experimental conditions are conventional methods and conditions known in the art.

[0069] Table 1 Aqueous resin emulsions involved in the examples

[0070]

[0071]

[0072] Table 2 Silicone feel additives and wax emulsions involved in the examples

[0073]

[0074] The solid content of the hand-feeling agent is about 20%, the pH is between 5-6, and it is weakly cationic;

[0075] The solid content of the wax emulsion is between 15-20%, the pH is between 9-11, and the ionicity is anionic / non-ionic.

[0076] Table 3 Formaldehyde removal materials involved in the examples

[0077]

[0078]

[0079] Table 4 Thickeners involved in the examples

[0080] Outsourcing Company Polyacrylate Dow, ASE-60 Associative polyurethane thickener Wanhua Corporation, U605 Hydroxyethyl Cellulose Shandong Yutian Chemical Co., Ltd.

[0081] Example 1

[0082] A leather auto seat sealant of the present embodiment is made of the following raw materials: 45kg of water-based resin emulsion, 40kg of deionized water, 5kg of silicone feel additive, 3kg of wax emulsion, 5kg of formaldehyde removal material, 1kg of wetting and leveling agent, 0.5kg of antibacterial preservative, 0.3kg of pH adjuster, 1kg of thickener, and 0.2kg of anti-settling agent.

[0083] Among them, the water-based resin emulsion is a water-based acrylic resin and a water-based polyurethane resin, which are mixed in a mass ratio of 1:2; the silicone feel additive is a polyether siloxane copolymer; the wax emulsion is a paraffin emulsion, and the formaldehyde-removing material is a negative ion aqueous solution and a nano-TiO2 photocatalyst aqueous solution, which are mixed in a mass ratio of 3:1; the wetting and leveling agent is a non-ionic surfactant (BASF, WE3220, polyether modified silicone, the same as in the following embodiments); the antibacterial preservative is benzisothiazolinone and 2-methyl-4-isothiazoline-3-one, which are mixed in a mass ratio of 1:1; the pH adjuster is a sodium hydroxide aqueous solution (Shandong Chicheng Chemical Co., Ltd., NaOH concentration 15%); the thickener is a polyurethane thickener and a polyacrylate thickener, which are mixed in a mass ratio of 1:3; the anti-settling additive is bentonite (Changan Renheng Company).

[0084] The preparation method of the leather seat sealant of the present embodiment comprises the following steps:

[0085] (1) Weighing the raw materials according to their weight for later use;

[0086] (2) Mix and stir the aqueous acrylic resin emulsion, aqueous polyurethane resin emulsion and deionized water uniformly at a stirring rate of 200 rpm / min for a dispersion time of 30 min, then add polyether siloxane copolymer, paraffin emulsion, negative ion aqueous solution and nano-TiO2 photocatalyst aqueous solution, nonionic surfactant, benzisothiazolinone, 2-methyl-4-isothiazoline-3-one in sequence at an addition interval of 20 min, keep the rotation speed during the period, the second stirring rate is 200-300 rpm / min, stir for 120 min, after stirring uniformly, add sodium hydroxide aqueous solution to adjust the pH to between 8 and 9, then add polyurethane thickener, polyacrylate thickener and bentonite, increase the rotation speed to 500 rpm / min, stir for 50 min, the viscosity is between 1000-1500 mPas, and the leather seat sealing agent is obtained, with a solid content of between 20-25%.

[0087] Example 2

[0088] A leather auto seat sealant of the present embodiment is made of the following raw materials: 50kg of water-based resin emulsion, 30kg of deionized water, 5kg of silicone feel additive, 5kg of wax emulsion, 8kg of formaldehyde removal material, 0.6kg of wetting and leveling agent, 0.2kg of antibacterial preservative, 0.2kg of pH adjuster, 0.8kg of thickener, and 0.2kg of anti-settling additive.

[0089] Among them, the water-based resin emulsion is a silicone-modified acrylic resin and a silicone-modified polyurethane resin, which are mixed in a ratio of 1:4; the silicone feel additive is a methyl silicone oil emulsion; the wax emulsion is an oxidized polyethylene wax emulsion; the formaldehyde-removing material is a negative ion aqueous solution and tea polyphenol powder, which are mixed in a ratio of 1:1; the wetting and leveling agent is a non-ionic surfactant (BASF); the antibacterial preservative is benzisothiazolinone and 2-methyl-4-isothiazoline-3-one, which are mixed in a ratio of 1:1; the pH adjuster is 2-amino-2-methyl-1-propanol (Dow Chemical); the thickener is hydroxyethyl cellulose and polyacrylate thickener, which are added in a ratio of 1:1; the anti-settling additive is sepiolite (Changan Renheng Company).

[0090] The preparation method of the leather seat sealant of the present embodiment comprises the following steps:

[0091] (1) Weighing the raw materials according to their weight for later use;

[0092] (2) The organic silicon modified acrylic resin and organic silicon modified polyurethane resin emulsions and deionized water are mixed and stirred uniformly at a stirring rate of 300 rpm / min and a dispersion time of 30 minutes. Then, methyl silicone oil emulsion, oxidized polyethylene wax emulsion, negative ion aqueous solution and tea polyphenol powder, nonionic surfactant, benzisothiazolinone, 2-methyl-4-isothiazoline-3-one are added in sequence at an interval of 10 minutes. The rotation speed is maintained during the period. The second stirring rate is 100-200 rpm / min and the stirring is performed for 120 minutes. After stirring uniformly, 2-amino-2-methyl-1-propanol is added to adjust the pH to between 8 and 9. Then, hydroxyethyl cellulose, polyacrylate thickener and sepiolite are added. The rotation speed is increased to 500 rpm / min and stirred for 50 minutes. The viscosity is between 1000 and 1500 mPas to obtain the leather seat sealing agent with a solid content of between 20 and 25%.

[0093] Example 3

[0094] A leather auto seat sealant of the present embodiment is made of the following raw materials: 40kg of water-based resin emulsion, 35kg of deionized water, 10kg of silicone feel aid, 5kg of wax emulsion, 10kg of formaldehyde removal material, 1kg of wetting and leveling agent, 0.5kg of antibacterial preservative, 0.2kg of pH adjuster, 1kg of thickener, and 0.4kg of anti-settling agent.

[0095] Among them, the water-based resin emulsion is acrylic resin and silicone-modified polyurethane resin, mixed in a ratio of 1:1; the silicone feel additives are amino silicone oil emulsion and methyl silicone oil emulsion, mixed in a ratio of 3:7; the wax emulsion is oxidized polyethylene wax emulsion; the formaldehyde-removing material is nano-TiO2 photocatalyst aqueous solution and tea polyphenol powder, mixed in a ratio of 2:1; the wetting and leveling agent is a non-ionic surfactant (BASF); the antibacterial preservative is benzisothiazolinone and 2-methyl-4-isothiazoline-3-one, mixed in a ratio of 1:1; the pH adjuster is 2-amino-2-methyl-1-propanol; the thickener is a polyurethane thickener and a polyacrylate thickener, added in a ratio of 1:2; the anti-settling additive is bentonite (Changan Renheng Company).

[0096] The preparation method of the leather seat sealant of the present embodiment comprises the following steps:

[0097] (1) Weighing the raw materials according to their weight for later use;

[0098] (2) The acrylic resin and the silicone-modified polyurethane resin emulsion and deionized water are mixed and stirred uniformly at a stirring rate of 300 rpm / min and a dispersion time of 30 minutes. Then, a mixed solution of methyl silicone oil emulsion and amino silicone oil emulsion, oxidized polyethylene wax emulsion, nano-TiO2 photocatalyst aqueous solution and tea polyphenol powder, anionic surfactant, benzisothiazolinone, 2-methyl-4-isothiazolin-3-one are added in sequence at an interval of 10 minutes. The rotation speed is maintained during the period. The second stirring rate is 200-300 rpm / min and the stirring is performed for 120 minutes. After stirring uniformly, 2-amino-2-methyl-1-propanol is added to adjust the pH to between 8 and 9. Then, a polyurethane thickener and a polyacrylate thickener are added. The rotation speed is increased to 700 rpm / min and stirred for 50 minutes. The viscosity is between 1000 and 1500 mPas to obtain the leather seat sealing agent with a solid content of between 20 and 25%.

[0099] The present invention compares the performance and process of the sealing agent prepared above with commercial products, as follows. The main component of the commercial product is resin emulsion; the blank is a leather sample that is not sprayed with sealing. Compared with the commercial products and blank samples, Examples 1-3 have better performance, mainly in terms of hand feel, VOC release, atomization value, sealing performance, etc. Through the adjustment of the process, it can be seen that the stability of the product of the present invention is higher than that of the commercial products, with fewer bubbles and good operating performance.

[0100] Table 5 Performance comparison of Examples 1-3

[0101]

[0102] Note: Please refer to the table below for specific evaluation criteria.

[0103] Table 6 Process comparison of Examples 1-3

[0104] Contrast effect Commercially available products Example 1 Example 2 Example 3 blank bubble part none none none —— stability Layering Stablize Stablize Stablize —— Leveling generally good good good ——

[0105] The present invention also compares film-forming properties, and the film-forming related test methods include: forming a film after water volatilization, and then conducting a mechanical property test (stretching machine), a water swelling resistance test (immersed in water), and a solvent swelling resistance test (immersed in solvent). From the film-forming properties in Table 7, the performance of Examples 1-3 is also better than that of commercially available products and blank samples.

[0106] Table 7 Comparison of film forming properties of Examples 1-3

[0107]

[0108] Table 8 is a comparison of the fogging values ​​of a single resin component; the test method includes: placing the leather in a sealed container, drying it in an oven at 50°C for 7 days, then weighing it, and comparing the mass before and after the test. The reduced mass is the part that is fogged and volatilized. From the results, the fogging values ​​of some resins and hand-feeling agents are very low, and they can maintain extremely low fogging values ​​without adding casein.

[0109] Table 9 is a comparison of formaldehyde and acetaldehyde removal rates; the test method includes: placing the leather in a bag, collecting volatiles, and then conducting an acetaldehyde test using a liquid phase mass spectrometer, while the formaldehyde removal rate is obtained by testing using the acetylacetone method.

[0110] Table 8 Comparison of atomization values

[0111]

[0112] Table 9 Comparison of formaldehyde and acetaldehyde removal rates

[0113]

[0114] In the embodiment of the present invention, the leather lining agent prepared is used to seal the leather blank, and the test process is as follows.

[0115] Table 10 Process flow on leather in the embodiment of the present invention

[0116]

[0117]

[0118] Table 11 Application performance indicators and evaluation methods

[0119]

[0120]

[0121] As can be seen from the above embodiments, the present invention mainly adopts a low-odor water-based resin emulsion, so that the overall odor of the sealing agent is low, and the conventional casein component is removed, and the atomization value is low. At the same time, the formaldehyde-removing material in the present invention can effectively reduce the content of formaldehyde and acetaldehyde, so that the overall VOC is low, and the strong sealing performance is mainly achieved by the water-based resin emulsion with strong adhesion and other materials. The leather sealing agent described in the present invention has excellent performance and is suitable for use in closed spaces such as car seats.

[0122] The above examples are only used to illustrate the technical features and implementation process of the present invention, rather than to limit the technical solution of the present invention. It should be pointed out that for ordinary technicians in this field, the present invention can still be modified or replaced by equivalents, and modifications or replacements that do not deviate from the principles of the present invention are all covered by the protection of the present invention.

Claims

1. A leather sealing agent with low fogging value and formaldehyde removal, characterized in that: The invention comprises the following raw materials in parts by weight: 30-60 parts of water-based resin emulsion; 30-60 parts water; 5-15 parts of silicone feel additives; 2-8 parts of wax emulsion; 5-15 parts of formaldehyde removal materials; 1-3 parts of wetting and leveling agent; 0.5-2 parts of thickener; 0.1-0.5 parts of anti-settling agent; The water-based resin emulsion is one or more of water-based polyurethane emulsion, water-based acrylic emulsion, silicone-modified polyurethane emulsion and silicone-modified acrylic emulsion; the formaldehyde-removing material is one or more of nano-photocatalyst titanium dioxide water dispersion, negative ion aqueous solution and tea polyphenol powder.

2. The leather sealing agent according to claim 1, characterized in that: The water-based resin emulsion has low odor and a solid content of 15-40%.

3. The leather sealing agent according to claim 1, characterized in that: The organosilicon hand-feeling additive is one or more of isomeric methyl silicone oil emulsion, amino silicone oil emulsion and polyether siloxane copolymer; the wax emulsion is paraffin wax emulsion and / or oxidized polyethylene wax emulsion.

4. The leather sealing agent according to claim 1, characterized in that: The wetting and leveling agent is an anionic surfactant and / or a nonionic surfactant; the thickener is one or more of polyacrylate, associative polyurethane thickener and hydroxyethyl cellulose.

5. The leather sealing agent according to claim 1, characterized in that: The anti-settling aid is one or more of sepiolite, bentonite and montmorillonite.

6. The leather sealing agent according to any one of claims 1 to 5, characterized in that: The leather sealing agent also includes 0.1-2 parts of a pH regulator and / or 0.1-1 parts of an antibacterial preservative.

7. The leather sealing agent according to claim 6, characterized in that: The antibacterial and preservative auxiliary agent is benzisothiazolinone and / or 2-methyl-4-isothiazolin-3-one; the pH regulator is 2-amino-2-methyl-1-propanol and / or a sodium hydroxide aqueous solution.

8. A method for preparing a leather sealing agent as claimed in any one of claims 1 to 7, comprising the following steps: The aqueous resin emulsion and water are mixed according to weight parts, and then silicone feel additives, wax emulsion, formaldehyde removal materials, wetting and leveling agents, optional antibacterial and antiseptic additives and pH adjusters are added in sequence under stirring conditions, and finally thickeners and anti-settling additives are added, and the material is filtered to obtain the leather sealing agent.

9. The preparation method according to claim 8, characterized in that: The stirring speed is 100-300 rpm / min; the mixing and stirring temperature is 15-35°C; The stirring speed for adding the thickener and the anti-settling aid is 300-700 rpm / min, the stirring time is 30-90 min, and the viscosity is 500-2000 mPa.s.

10. Use of the leather sealing agent according to any one of claims 1 to 7 in the treatment of seat leather lining.

Images