A water-based color rubbing paint for artificial leather and preparation method thereof

Abstract

The invention relates to the technical field of coatings, and discloses a water-based rubbing paint for artificial leather and a preparation method thereof. The water-based rubbing paint for artificial leather comprises the following components by weight: 30 to 40 parts of polyurethane, 30 to 50 parts of wax mixture, 50 to 90 parts of deionized water, 3 to 5 parts of filler, 0.5 to 2 parts of leveling agent, and 0.5 to 2 parts of hand feeling agent. The water-based rubbing paint uses polyurethane to form a dense and continuous film layer on the leather, and the wax mixture is used to improve the hand feeling, glossiness, and waterproof performance of the coating, so as to improve the waterproof performance and wet rubbing resistance of the coating; and fillers, leveling agents, and hand feeling agents are added as additives to improve the glossiness, leveling, scratch resistance, and wear resistance of the coating.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, in particular to a water-based color rubbing coating for artificial leather and a preparation method thereof. Background Art

[0002] As people's awareness of environmental protection continues to increase and their requirements for product safety increase, the application of water-based coatings in various fields has received more and more attention, and the field of artificial leather rubbing paint is no exception.

[0003] Traditional solvent-based rubbing paints, especially those with nitrocellulose varnish as the main ingredient, show good adhesion on synthetic leather and genuine leather. This is mainly attributed to the fact that the organic solvents contained in nitrocellulose varnish solvent-based paints can effectively penetrate into the fiber structure of the leather, forming an "anchoring" effect after drying, which makes the paint tightly bonded to the leather surface, thereby ensuring good adhesion.

[0004] However, this type of solvent-based paint has many disadvantages. First, the large-scale use of organic solvents will not only cause serious environmental pollution, but also organic solvents are flammable and explosive, which poses a great safety hazard during production, storage and use. Secondly, from a performance perspective, although its adhesion performance is excellent, the chemical bonding method between the film-forming substance of the solvent-based paint and the leather is relatively simple, mainly relying on physical penetration and some weaker chemical bonds.

[0005] In contrast, water-based rubbing paint uses water as a dispersion medium, and has the advantages of being environmentally friendly, non-toxic, and non-flammable, which is in line with the sustainable development trend of modern industry. However, at present, there is a significant gap between water-based rubbing paint and solvent-based rubbing paint in terms of waterproof performance and wet rubbing resistance. This is mainly due to the molecular structure characteristics of water-based resins. Water-based resin molecules usually contain more hydrophilic groups, such as carboxyl and hydroxyl groups. These hydrophilic groups will make the coating surface have a certain hydrophilicity after the coating film is formed. When encountering water or a humid environment, water molecules can easily penetrate into the coating through these hydrophilic groups, destroying the bonding force between the coating and the leather, and then causing the waterproof performance and wet rubbing resistance of the coating to decrease. In addition, during the drying process of water-based paint, the volatilization rate of water is relatively slow, which may affect the density of the coating, resulting in more pores and defects in the coating, further reducing its resistance to water and friction.

[0006] In summary, although water-based rubbing paint has environmental advantages, how to improve its waterproof performance and wet-rubbing resistance so that it can be comparable to or even surpass solvent-based rubbing paint in comprehensive performance has become a key technical problem that needs to be urgently solved in the current field of artificial leather rubbing paint. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a water-based rubbing paint for artificial leather and a preparation method thereof, aiming to improve the waterproof performance and wet rubbing resistance of the water-based rubbing paint in artificial leather applications.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A water-based color rubbing paint for artificial leather comprises the following components by weight: 30-40 parts of polyurethane, 30-50 parts of wax mixture, 50-90 parts of deionized water, 3-5 parts of filler, 0.5-2 parts of leveling agent and 0.5-2 parts of hand feeling agent.

[0010] The water-based rubbing paint for artificial leather, wherein the polyurethane is one of polyester resin and polyether resin; the glossiness of the polyester resin and the polyether resin is 70-90gu, and the modulus is 1-5MPa.

[0011] The water-based color rubbing paint for artificial leather comprises: the solid content of the polyester resin is 40%, and the solid content of the polyether resin is 25%.

[0012] The water-based color rubbing paint for artificial leather, wherein the wax mixture is a mixture of palm wax, burnt black wax and waterproof wax.

[0013] The water-based color rubbing paint for artificial leather, wherein the filler is silicon dioxide powder.

[0014] The water-based color rubbing paint for artificial leather, wherein the particle size of the silicon dioxide powder is 7-20nm.

[0015] The water-based color rubbing paint for artificial leather, wherein the leveling agent is an organosilicon leveling agent.

[0016] The water-based color rubbing paint for artificial leather, wherein the hand feeling agent is ultra-high molecular weight polydimethylsiloxane.

[0017] A method for preparing a water-based color rubbing coating for artificial leather comprises the following steps:

[0018] Add the above-mentioned polyurethane and wax mixture in parts by weight and 30% to 50% of deionized water in a mixing tank and stir evenly;

[0019] Add filler, leveling agent and feel agent into the mixing tank and mix well;

[0020] According to the requirements of the viscosity and solid content of the coating, the remaining deionized water is added and stirred evenly to obtain the water-based color rubbing coating for artificial leather.

[0021] The method for preparing the water-based color rubbing paint for artificial leather further comprises the step of sieving the prepared paint, wherein the mesh number of the sieve is 100-200 meshes.

[0022] Beneficial effects:

[0023] The invention provides a water-based rubbing paint for artificial leather and a preparation method thereof. The water-based rubbing paint uses polyurethane to form a dense and continuous film layer on the leather, and is supplemented with a wax mixture to improve the feel, glossiness and waterproof performance of the coating, so as to improve the waterproof performance and wet rubbing resistance of the coating; and fillers, leveling agents and hand feeling agents are added as additives to improve the glossiness, leveling and scratch resistance and wear resistance of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a real picture of artificial leather treated with the coating prepared in Example 1. DETAILED DESCRIPTION

[0025] The present invention provides a water-based color rubbing paint for artificial leather and a preparation method thereof. In order to make the purpose, technical scheme and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the scope of protection of the present invention.

[0026] See also Figure 1 The present invention provides a water-based color rubbing paint for artificial leather, which comprises the following components by weight: 30 to 40 parts of polyurethane, 30 to 50 parts of wax mixture, 50 to 90 parts of deionized water, 3 to 5 parts of filler, 0.5 to 2 parts of leveling agent, and 0.5 to 2 parts of hand feeling agent.

[0027] Polyurethane acts as an adhesive in the coating system. It has certain flexibility and wear resistance. Its molecular structure can form a stable, dense, continuous and elastic film layer on the leather surface. This film can block the intrusion of water to a certain extent. At the same time, when it is subjected to wet rubbing, it can buffer the damage to the coating caused by external forces and reduce the possibility of the coating being rubbed off, thereby improving the wet rubbing resistance. In addition, polyurethane has good adhesion to the leather surface, which helps the entire coating system to adhere to the leather, ensures the integrity of the coating under various use conditions, and indirectly enhances the waterproof and wet rubbing resistance.

[0028] The wax mixture in the system plays a role in improving the feel and glossiness of the coating, as well as improving the waterproof performance of the coating. Specifically, after drying, it can form a hydrophobic wax layer on the leather surface, which can appropriately improve the waterproof effect of the coating.

[0029] Deionized water, as a dispersion medium, ensures the stability and uniformity of the coating system, enables the components to be fully mixed and evenly distributed on the leather surface, helps to form a complete and continuous coating, and avoids the degradation of waterproof and wet-rub resistance due to local defects.

[0030] The right amount of filler can fill the tiny pores inside the coating, making the coating denser and reducing the channels for water penetration, thereby improving the waterproof performance. At the same time, fillers can also increase the hardness and wear resistance of the coating, and improve the wet rubbing resistance to a certain extent. In addition, it can also be used to adjust the glossiness of the layer on the leather.

[0031] The leveling agent can make the coating spread evenly on the leather surface to form a smooth and flat coating. The smooth coating surface can reduce the accumulation and penetration of water on the coating, which is beneficial to improve the waterproof performance. In the wet rubbing process, it reduces the friction resistance caused by the uneven surface, reduces the risk of coating damage, and improves the wet rubbing resistance.

[0032] While improving the feel of the coating, the hand feel agent also helps to improve the coating's scratch resistance, wear resistance and wet rub resistance. It can form a lubricating layer on the coating surface to reduce the friction when the coating is wet rubbed, thereby reducing the wear of the coating and maintaining the integrity and waterproof performance of the coating.

[0033] Through the synergistic effect of the above components, the water-based rubbing paint can effectively solve the problems of poor waterproof performance and wet rubbing resistance, making it closer to or even better than traditional solvent-based rubbing paint in performance.

[0034] Specifically, the polyurethane is one of polyester resin or polyether resin; the gloss of the polyester resin and polyether resin is 70-90gu and the modulus is 1-5MPa. After film formation, the high-gloss low-modulus polyester resin and polyether resin can form a continuous and dense polymer film on the surface of artificial leather. This film has certain flexibility and barrier properties, which can effectively block the invasion of water molecules and reduce the direct contact between water and the leather surface, thereby improving the waterproof performance. In addition, the polymer material formed by the reaction of polyester polyol and polyisocyanate, polyether polyol and polyisocyanate contains a variety of active groups in its molecular structure, which can chemically bond or physically adsorb with the groups on the leather surface, so that the coating is firmly attached to the surface of artificial leather. During the wet rubbing process, good adhesion can ensure that the coating is not easily wiped off, maintain the integrity of the coating, and thus improve the wet rubbing resistance.

[0035] More specifically, the polyester resin may be a product of Guangdong Yinyang Environmental Protection New Materials Co., Ltd., model PU-303. The polyether resin may be a product of Guangdong Yinyang Environmental Protection New Materials Co., Ltd., model 69208.

[0036] Specifically, the solid content of the polyester resin is 40%, and the solid content of the polyether resin is 25%. If the solid content of the resin is too high or too low, the film-forming effect will be affected. If the solid content is too high, the distance between the resin particles is small, and the movement of the molecular chain is restricted during the film-forming process, which will lead to uneven film formation and defects such as shrinkage holes and orange peel, thereby affecting the waterproof and wet-rubbing resistance of the coating; if the solid content is too low, the coating will be thin and poor in density after film formation, and it will not be able to effectively block moisture and resist friction, which will also reduce the waterproof and wet-rubbing resistance. In addition, the appropriate solid content can make the polymer network structure formed by the resin more regular and stable, thereby giving the coating good mechanical properties, such as hardness, flexibility and adhesion. Inappropriate solid content may cause the coating to be too hard or too soft. A coating that is too hard has poor flexibility and is easy to crack and fall off when wet-rubbing; a coating that is too soft cannot withstand friction, affecting the wet-rubbing resistance, and may also reduce the adhesion to the leather, thereby affecting the overall performance. Appropriate solid content also helps the resin to better compatibility and synergy with other components in the coating, such as fillers, leveling agents, and feel agents.

[0037] Specifically, the wax mixture is a mixture of palm wax, burnt black wax and waterproof wax. Palm wax and burnt black wax have the effect of polishing and burnt black, and waterproof wax can be used to improve the waterproof effect of the coating. After the coating dries, the mixture of palm wax, burnt black wax and waterproof wax will migrate to the surface of the coating to form a highly hydrophobic wax layer. This wax layer can significantly reduce the surface energy of the coating surface, making it difficult for water molecules to spread and penetrate on the coating surface, just like putting a layer of "waterproof clothing" on the coating, greatly enhancing the waterproof performance of the coating. The wax layer itself has good wear resistance. When wet rubbing, it can reduce the damage to the coating caused by external friction, and play a buffering and protective role. At the same time, the low friction coefficient characteristics of the wax layer reduce the friction on the coating surface during wet rubbing, further reducing the risk of wear of the coating, thereby improving the wet rubbing resistance.

[0038] Specifically, the filler is silica powder. As a filler, silica powder can fill tiny pores and defects in the coating, making the coating more dense and uniform. This not only reduces the channels for water penetration and improves the waterproof performance, but also increases the hardness and mechanical strength of the coating, making the coating less likely to be damaged during wet rubbing and enhancing the wet rubbing resistance.

[0039] Specifically, the particle size of the silicon dioxide powder is 7 to 20 nm. The silicon dioxide in this particle size range has good transparency and stability, and can be used in water-based rubbing paint to make the coating more delicate and smooth, and help improve the gloss and transparency of the coating.

[0040] Specifically, the leveling agent is an organosilicon leveling agent. The organosilicon leveling agent can make the coating spread quickly on the surface of the artificial leather and form a flat and smooth coating. The smooth coating surface is not easy to accumulate water, which can reduce the residence time and penetration opportunity of water on the coating, which is conducive to improving the waterproof performance. At the same time, the flat coating can reduce the local stress concentration and friction resistance caused by the uneven surface during the wet rubbing process, reduce the possibility of the coating being rubbed off, and improve the wet rubbing resistance.

[0041] More specifically, the organosilicon leveling agent is a polyether-modified organopolysiloxane or an alkyl-modified organopolysiloxane. By introducing a polyether segment into the polysiloxane molecule, the compatibility and surface activity of the polyether-modified organopolysiloxane can be adjusted, so that it has good solubility and dispersibility in the water-based system, can effectively reduce the surface tension of the coating, and promote the coating to form a flat and smooth coating during the film-forming process. Alkyl-modified organosiloxane uses alkyl groups to modify polysiloxane, which can improve its thermal stability, compatibility and foam instability, and even has a defoaming function, which helps to improve the leveling and construction performance of the coating.

[0042] Specifically, the hand feeling agent is ultra-high molecular weight polydimethylsiloxane. While improving the hand feeling of the coating, the hand feeling agent can also form a lubricating film on the surface of the coating, which can reduce the friction between the coating and the wiped object during wet wiping, reduce the wear of the coating, and help maintain the integrity and waterproof performance of the coating. For example, a product of Dow Corning, model DC-51, can be used.

[0043] The present invention also provides a method for preparing a water-based color rubbing coating for artificial leather, comprising the following steps:

[0044] (1) Add the above-mentioned polyurethane and wax mixture in parts by weight and deionized water accounting for 30% to 50% of the total water volume into a stirring tank and stir for 5 to 10 minutes. Premix the polyurethane and wax mixture first to allow the resin and wax mixture to swell and disperse fully, which is conducive to forming a uniform resin emulsion mixture.

[0045] (2) Add filler, leveling agent and feel agent into the mixing tank and stir for 5 to 10 minutes to ensure that the additives are evenly dispersed in the coating system.

[0046] (3) According to the requirements of the viscosity and solid content of the coating, the remaining deionized water is added and stirred for 10 to 20 minutes to obtain the water-based rubbing paint for artificial leather. This step is used to adjust the viscosity of the coating to a suitable construction viscosity range.

[0047] (4) Filtering the prepared water-based color rubbing paint for artificial leather through a filter screen with a mesh size of 100 to 200 meshes. The purpose of this step is to remove impurities, undispersed particles, etc. in the paint to ensure the quality and stability of the paint.

[0048] In order to further illustrate the water-based color rubbing coating for artificial leather and the preparation method thereof provided by the present invention, the following examples are provided.

[0049] Example 1

[0050] The invention discloses a water-based color rubbing paint for artificial leather, which comprises the following components by weight: 30-40 parts of polyurethane (polyester resin with a solid content of 40%, a glossiness of the resin of 78gu and a modulus of 3MPa), 30-50 parts of wax mixture, 50-90 parts of deionized water, 3-5 parts of silicon dioxide powder, 0.5-2 parts of an organosilicon leveling agent and 0.5-2 parts of a hand feeling agent.

[0051] A method for preparing a water-based color rubbing coating for artificial leather comprises the following steps:

[0052] (1) Add the above-mentioned polyurethane and wax mixture in parts by weight and deionized water accounting for 45% of the total water volume into a stirring tank and stir for 10 minutes.

[0053] (2) Add filler, leveling agent and feel agent into the mixing tank and stir for 10 minutes.

[0054] (3) Add the remaining deionized water according to the viscosity and solid content requirements of the coating and stir for 10 minutes.

[0055] (4) The prepared water-based rubbing paint for artificial leather is filtered through a filter screen having a mesh size of 200 meshes.

[0056] Example 2

[0057] The invention discloses a water-based color rubbing paint for artificial leather, which comprises the following components by weight: 30-40 parts of polyurethane (polyester resin with a solid content of 40%, a glossiness of the resin of 78gu and a modulus of 3MPa), 30-50 parts of wax mixture, 50-90 parts of deionized water, 3-5 parts of silicon dioxide powder, 0.5-2 parts of an organosilicon leveling agent and 0.5-2 parts of a hand feeling agent.

[0058] Example 3

[0059] The invention discloses a water-based color rubbing paint for artificial leather, which comprises the following components by weight: 30-40 parts of polyurethane (polyether resin with a solid content of 25%, a glossiness of the resin of 87gu and a modulus of 2MPa), 30-50 parts of a wax mixture, 50-90 parts of deionized water, 3-5 parts of silicon dioxide powder, 0.5-2 parts of an organosilicon leveling agent and 0.5-2 parts of a hand feeling agent.

[0060] Take the water-based rubbing paint prepared in Example 1, add water-based color paste, add appropriate amount and color according to your needs, use a three-plate printing machine with 100 mesh to dry once, and then use 150 mesh to dry once, the drying temperature is 100-130°C. Then, according to the required effect, partially or fully throw out the retro features you need on the polishing machine, as shown in the actual picture Figure 1 shown.

[0061] Performance Testing

[0062] Glossiness: According to GB / T 9754-2007 Paints and varnishes without metallic pigments Waterproof performance of paint film: According to GB / T 1733-1993 Determination of water resistance of paint film

[0063] Wet rub resistance: According to QB / T 2714-2005 leather physical and mechanical test surface color fastness

[0064] Adhesion: Adopting the 100-grid method for adhesion test

[0065] The results are shown in the following table:

[0066]

[0067] from Figure 1 As can be seen from the above data, the water-based rubbing paint of the present invention can achieve high oil wax gloss while satisfying the visual effect of leather. The waterproof performance, wet rubbing resistance, and adhesion of the coating formed after the water-based rubbing paint is dried are comparable to those of traditional solvent-based rubbing paint.

[0068] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the present invention.

Claims

1. A water-based color rubbing paint for artificial leather, characterized in that: The composition includes the following components by weight: 30-40 parts of polyurethane, 30-50 parts of wax mixture, 50-90 parts of deionized water, 3-5 parts of filler, 0.5-2 parts of leveling agent and 0.5-2 parts of hand feeling agent.

2. The water-based color rubbing paint for artificial leather according to claim 1, characterized in that: The polyurethane is one of polyester resin and polyether resin; the glossiness of the polyester resin and the polyether resin is 70-90gu and the modulus is 1-5MPa.

3. The water-based color rubbing paint for artificial leather according to claim 2, characterized in that: The solid content of the polyester resin is 40%, and the solid content of the polyether resin is 25%.

4. The water-based color rubbing paint for artificial leather according to claim 1, characterized in that: The wax mixture is a mixture of palm wax, burnt black wax and waterproof wax.

5. The water-based color rubbing paint for artificial leather according to claim 1, characterized in that: The filler is silicon dioxide powder.

6. The water-based color rubbing paint for artificial leather according to claim 5, characterized in that: The particle size of the silicon dioxide powder is 7 to 20 nm.

7. The water-based color rubbing paint for artificial leather according to claim 1, characterized in that: The leveling agent is an organosilicon leveling agent.

8. The water-based color rubbing paint for artificial leather according to claim 1, characterized in that: The hand feeling agent is ultra-high molecular weight polydimethylsiloxane.

9. A method for preparing a water-based color rubbing coating for artificial leather, characterized in that: The steps include: Add the above-mentioned polyurethane and wax mixture in parts by weight and 30% to 50% of deionized water in a mixing tank and stir evenly; Add filler, leveling agent and feel agent into the mixing tank and mix well; According to the requirements of the viscosity and solid content of the coating, the remaining deionized water is added and stirred evenly to obtain the water-based rubbing coating for artificial leather as claimed in any one of claims 1 to 8.

10. The method for preparing the water-based color rubbing paint for artificial leather according to claim 9, characterized in that: The method also includes the step of sieving the prepared coating, wherein the mesh number of the sieve is 100 to 200 meshes.

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