Immersive quiet PU leather and preparation method thereof

Abstract

The invention relates to the technical field of artificial leather, in particular to immersion type quiet PU leather and a preparation method thereof.The immersion type quiet PU leather comprises base cloth, one face of the base cloth is bonded with a middle layer through a high-stripping-force bonding layer, and the face, away from the base cloth layer, of the middle layer is coated with a water-based coating layer; the water-based coating layer is prepared from the following raw materials in parts by weight: 50 to 90 parts of a matting surface treatment agent, 10 to 50 parts of a brightening surface treatment agent, 5 to 8 parts of a cross-linking agent, 3 to 6 parts of a wear-resistant agent, 0.5 to 2 parts of a flatting agent, 0.1 to 0.5 part of a penetrating agent, 0.1 to 3 parts of a mutual solvent, 3 to 10 parts of a noise reduction auxiliary agent and 10 to 40 parts of water; the penetrating agent is alkyl glycoside; the method has the advantage of improving the noise reduction performance of the PU leather.

Description

Technical Field

[0001] The present application relates to the technical field of artificial leather, and in particular to an immersive quiet PU leather and a preparation method thereof. Background Art

[0002] Since natural leather has a long production cycle, limited quantity, and is expensive, synthetic leather has become its substitute. As a high-quality substitute for natural leather, PU leather is widely used in people's production and life. PU leather produced by traditional methods mostly uses water-based polyurethane resin as raw material and water, acetone or DMF as solvent. The finished PU leather has the characteristics of non-flammability and good toughness, and is widely used in furniture, outdoor leather goods, shoes and bags, car interiors, etc.

[0003] With the development of production economy, there are new requirements for PU leather used in car interiors. In the past, the main work of automobile NVH was to reduce vibration and noise. With the development of technology, the radiated noise of most sound sources has been reduced. The traditional sound pressure level and 1 / 3 octave evaluation standards can no longer reflect people's subjective judgment on noise. Although some sounds have a high sound pressure level, they make people feel more pleasant. Under such circumstances, the concept of sound quality came into being. The "sound" in the definition does not refer to a physical process such as a simple sound wave, but to the auditory perception process of the human ear. "Quality" refers to the subjective judgment made by the human ear on the perception process of sound events. This concept emphasizes the subjectivity of people's judgment on sound characteristics.

[0004] Although in the era of roaring fuel, car manufacturers have achieved the ultimate in quietness in cars, but with the increasing share of new energy in the automotive market, the previous "ultimate" can no longer meet the needs of an era without engine roar, so car manufacturers and consumers need an interior covering material that can better meet the high quietness of the new automotive era; and the current PU leather cannot meet this requirement well. Summary of the invention

[0005] In order to improve the sound-absorbing and noise-reducing performance of PU leather, the present application provides an immersive and quiet PU leather and a preparation method thereof.

[0006] In the first aspect, the present application provides an immersive and quiet PU leather, which adopts the following technical solutions: An immersive quiet PU leather, comprising a base fabric, one side of the base fabric is bonded with a middle layer through a high peeling force adhesive layer, and the side of the middle layer away from the base fabric layer is coated with a water-based finishing layer; the water-based finishing layer comprises the following raw materials in parts by weight: 50-90 parts of a matte surface treatment agent, 10-50 parts of a gloss-enhancing surface treatment agent, 5-8 parts of a cross-linking agent, 3-6 parts of an anti-wear agent, 0.5-2 parts of a leveling agent, 0.1-0.5 parts of a penetrant, 0.1-3 parts of a mutual solvent, 3-10 parts of a sound-absorbing and noise-reducing auxiliary agent, and 10-40 parts of water; The noise reduction auxiliary agent is vermiculite, and the penetrant is alkyl polyglycoside.

[0007] By adopting the above technical scheme, vermiculite has a large specific surface area and internal pores. Adding it to the water-based coating layer can play an auxiliary role in sound insulation and noise reduction; alkyl glycoside has low surface tension, good solubility in water, and strong wetting ability. By using alkyl glycoside as a penetrant, it can be adsorbed on the surface of the sound insulation and noise reduction auxiliary agent, promote the mutual penetration between the organic raw materials and the inorganic raw materials of the water-based coating layer, make the integrity of the water-based coating layer stronger, and greatly reduce the dynamic friction coefficient of the surface of the PU leather, thereby improving its sound insulation and noise reduction performance.

[0008] Preferably, the penetrant is prepared by esterification reaction of alkyl polyglycoside, hydroxy silane coupling agent and carboxyl-terminated hyperbranched polyester, and the preparation method is as follows: Under nitrogen atmosphere, using DMF as solvent, n-butanol as water-carrying agent, and p-toluenesulfonic acid as catalyst, 13-17 parts by weight of terminal carboxyl hyperbranched polyester, 0.4-0.6 parts by weight of alkyl glycoside, and 0.2-0.6 parts by weight of hydroxy silane coupling agent are added, the temperature is raised to 145-155° C., the reaction is stirred, and the solvent is removed to obtain a penetrant.

[0009] By adopting the above technical scheme, based on the good foaming property of alkyl polyglycoside, after it is added to the water-based coating layer, the water-based coating layer has rich and delicate foam, which is not conducive to the flatness of the PU leather surface, and is prone to depression, increasing its surface dynamic friction coefficient. In addition, the alkyl polyglycoside has a strong thickening ability. After addition, it leads to poor dispersion ability in the system, and its thickening effect is not conducive to the dispersion of the sound-absorbing and noise-reducing auxiliary agent. Based on this, by grafting it with a hyperbranched polymer, due to the extremely low viscosity of the hyperbranched polymer and high solubility in water, its thickening effect can be reduced after grafting; at the same time, it is grafted with a silane coupling agent, and the effect of the organic silicon compound can reduce the foaming of the alkyl polyglycoside, and its silane coupling agent can also be coupled with the sound-absorbing and noise-reducing auxiliary agent, and the penetration effect of the alkyl polyglycoside is mutually promoted; under multiple effects, the affinity between the sound-absorbing and noise-reducing auxiliary agent and each raw material is greatly promoted, making the integrity of the water-based coating layer stronger, thereby further reducing the dynamic friction coefficient of the PU leather and improving its sound-absorbing and noise-reducing effect.

[0010] Preferably, the average molecular weight of the carboxyl-terminated hyperbranched polyester is in the range of 1000-6400.

[0011] By adopting the above technical scheme, the molecular weight of the carboxyl-terminated hyperbranched polyester is a key factor affecting the permeability of the penetrant, and its molecular weight should not be too low or too high. The technical effect is better within this range.

[0012] Preferably, the hydroxysilane coupling agent is 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane.

[0013] By adopting the above technical solution, the molecule contains two hydrogen bonds and is relatively easy to react with the terminal carboxyl hyperbranched polyester.

[0014] Preferably, the added amount of the 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane is 0.4 parts by weight.

[0015] By adopting the above technical solution, if too much silane coupling agent is added, the viscosity of the system will increase easily, which is not conducive to the dispersibility of the penetrant and the permeability of the alkyl polyglycoside; if too little silane coupling agent is added, its coupling effect is weak and the promoting effect is insufficient.

[0016] Preferably, the added amount of the penetrant is 0.3 parts by weight.

[0017] By adopting the above technical solution, the penetrant with the best penetration performance has a better technical effect when the addition amount is 0.5 parts by weight, but compared with the addition of 0.3 parts by weight, the optimization effect is smaller. Considering the comprehensive economic cost, the better addition amount is 0.3 parts by weight.

[0018] Preferably, the middle layer comprises the following raw materials in parts by weight: 95-100 parts of PU resin, 55-70 parts of DMF, 15-25 parts of ethyl acetate and 7-28 parts of color paste.

[0019] Preferably, the high release force adhesive layer comprises the following raw materials in parts by weight: 95-100 parts of solvent-free adhesive A, 100-110 parts of solvent-free adhesive B, 0.045-0.1 parts of accelerator, 0.3-0.9 parts of curing agent, 0.25-0.55 parts of leveling agent and 35-55 parts of flame retardant.

[0020] In the second aspect, the present application provides a method for preparing an immersive quiet PU leather, which adopts the following technical solution: A method for preparing immersive quiet PU leather comprises the following steps: S1. Mix the raw materials of the middle layer to obtain a middle layer mixture, apply the middle layer mixture on the release paper, heat and dry it to obtain a drying layer; apply the middle layer mixture on the drying layer again, heat and dry it to obtain a middle layer; S2, mixing the raw materials of the high release force adhesive layer to obtain a high release force adhesive layer mixture, applying the high release force adhesive layer mixture to the surface of the middle layer, and then pre-baking it to a semi-dry pasting state, and then laminating it with the base fabric, drying it, and then separating the release paper, the one side of the separated release paper is a PU texture surface, and the applied high release force adhesive layer mixture forms a high release force adhesive layer; S3. Stir and mix the raw materials of the water-based coating layer to obtain a water-based coating layer mixture, apply the mixture to the PU texture surface with a roller, and dry it to obtain an immersive quiet PU leather.

[0021] By adopting the above technical scheme, the preparation method of the present application does not require special processes or equipment modification, is easy to operate, has low technical requirements for workers, has a high qualified rate of the prepared products, and is suitable for large-scale production.

[0022] In summary, the present application includes at least one of the following beneficial technical effects: 1. Vermiculite has a large specific surface area and internal pores. Adding it to the water-based coating layer can play an auxiliary role in sound insulation and noise reduction. Alkyl polyglycoside has low surface tension, good solubility in water, and strong wetting ability. By using alkyl polyglycoside as a penetrant, it can be adsorbed on the surface of the sound insulation and noise reduction additive, promoting the mutual penetration between the organic raw materials and inorganic raw materials of the water-based coating layer, making the integrity of the water-based coating layer stronger, and greatly reducing the dynamic friction coefficient of the surface of the PU leather, thereby improving its sound insulation and noise reduction performance.

[0023] 2. The longitudinal dynamic friction coefficient of the PU leather prepared in the present application is 0.34 or less, and the lateral dynamic friction coefficient is 0.35 or less; and through testing, its RPN is ≤1, which is far lower than the industry standard; this shows that the PU leather prepared in the present application has excellent sound-absorbing and noise-reducing performance, and its application potential has been greatly improved. DETAILED DESCRIPTION

[0024] The present application is further described in detail below in conjunction with the specific contents.

[0025] raw material The raw materials of this application are all purchased from the market, among which the model of the matte surface treatment agent is Tosoh E-1011; the model of the gloss-enhancing surface treatment agent is DX-1030; the model of the cross-linking agent is S8610; the model of the wear-resistant agent is W3351; the model of the leveling agent is KMT-5510; the mutual solvent is silane coupling agent KH550; the sound-absorbing and noise-reducing auxiliary agent is vermiculite powder with a particle size of 800 mesh; the model of the PU resin is PU-8202; the color paste is purchased from Guangzhou Mok Chemical Co., Ltd.; the curing agent is dicalcium phosphate; the model of the flame retardant is 6502-1; and the model of the accelerator is TIN-22.

[0026] Preparation Example Preparation Example 1 A penetrant, the preparation method of which is as follows: Under nitrogen atmosphere, 15 g of terminal carboxyl hyperbranched polyester was added to 200 mL of DMF, 60 mL of n-butanol was added as a water-carrying agent, 0.3 g of p-toluenesulfonic acid was added as a catalyst, and then 0.5 g of alkyl glycoside and 0.4 g of 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane were added, the temperature was raised to 150°C, the reaction was stirred for 15 hours, and the solvent was removed by reduced pressure distillation to obtain a penetrant; wherein, the average molecular weight of the terminal carboxyl hyperbranched polyester was 2600, and the corresponding specification model was HyPer C102; the alkyl glycoside was APG0810.

[0027] Preparation Example 2 A penetrant, which is different from Preparation Example 1 in that the average molecular weight of its carboxyl-terminated hyperbranched polyester is 1000, and the corresponding specification model is HyPer C101, and the remaining steps are the same as Preparation Example 1.

[0028] Preparation Example 3 A penetrant, which is different from Preparation Example 1 in that the average molecular weight of its terminal carboxyl hyperbranched polyester is 6400, the corresponding specification model is HyPer C103, and the remaining steps are the same as Preparation Example 1.

[0029] Preparation Example 4 A penetrant, which is different from Preparation Example 1 in that the added amount of 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane is 0.1 g, and the remaining steps are the same as Preparation Example 1.

[0030] Preparation Example 5 A penetrant, which is different from Preparation Example 1 in that the added amount of 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane is 0.6 g, and the remaining steps are the same as Preparation Example 1. Example

[0031] Example 1 An immersive quiet PU leather comprises a base fabric layer, one side of the base fabric layer is bonded with a middle layer through a high peeling force adhesive layer, and the side of the middle layer away from the base fabric layer is coated with a water-based finishing layer; the raw materials of each layer of the PU leather and the amount of each raw material are shown in Table 1, and the specific preparation method of the PU leather is as follows: S1. According to the raw material addition amounts in Table 1, DMF, ethyl acetate and color paste are added to the PU resin to obtain a middle layer mixture, and a release paper is taken; after stirring evenly, the middle layer mixture is applied to the release paper, and the coating thickness is 0.20±0.01mm. The vehicle speed is controlled at 10±1m / min, and the mixture is heated and dried. The oven is heated in a stepwise manner, and the temperatures are 70, 80, 100, 110, 125, and 125°C, respectively. The drying time is 4min in total, and a drying layer is obtained; The middle layer mixture is coated on the drying layer again, the coating thickness is 0.25±0.01mm, the vehicle speed is controlled at 10±1m / min, heated and dried, the oven temperature is increased step by step, the temperature is 70, 80, 100, 110, 125, 125℃, the drying time is 4min in total, and the middle layer is obtained; S2. According to the raw material addition amounts in Table 1, the raw materials of the high release force bonding layer are mixed to obtain a high release force bonding layer mixture, and the high release force bonding layer mixture is applied to the surface of the middle layer, and the coating thickness is 0.35±0.01mm, and the vehicle speed is controlled at 10±1m / min; the high release force bonding layer mixture is pre-baked to a semi-dry pasting state, and the semi-dry pasting step temperature is 100, 100, 100, 110, 125, and 125°C; then it is laminated to the base fabric and dried, and the oven is heated in a stepwise manner, and the temperatures are 135, 135, 135, 140, 140, 140, 140, 140, 145, 145, 145, 145, 145°C, and the drying time is 12min in total, and then the release paper is separated, and one side of the separated release paper is a PU texture surface, and the applied high release force bonding layer mixture forms a high release force bonding layer; S3. According to the raw material addition amounts in Table 1, the raw materials of the water-based finishing layer are stirred and mixed to obtain a water-based finishing layer mixture, and the mixture is rolled onto the PU texture surface using a roller coater. The speed is controlled at 9±2 m / min, and the mixture is dried. The drying temperatures are 125, 130, 130, 130, 130, 130°C, respectively, and the drying time is 4 min. After drying, the mixture is curled to obtain an immersive quiet PU leather. Among them, the penetrant in the water-based coating layer is alkyl polyglycoside APG0810; the solvent-free adhesive material A is a mixture of 60 kg of polyhexane adipate diol, 7 kg of 1,4-butanediol and 33 kg of diphenylmethane diisocyanate; and the solvent-free adhesive material B is stannous octoate.

[0032] Table 1 Raw materials and amounts of raw materials in Example 1 (kg) Example 2 An immersive quiet PU leather, which is different from Example 1 in that its penetrant comes from Preparation Example 1, and the remaining steps are the same as Example 1.

[0033] Example 3 An immersive quiet PU leather, which is different from Example 1 in that its penetrant comes from Preparation Example 2, and the remaining steps are the same as Example 1.

[0034] Example 4 An immersive quiet PU leather, which is different from Example 1 in that its penetrant comes from Preparation Example 3, and the remaining steps are the same as Example 1.

[0035] Example 5 An immersive quiet PU leather, which is different from Example 1 in that its penetrant comes from Preparation Example 4, and the remaining steps are the same as Example 1.

[0036] Example 6 An immersive quiet PU leather, which is different from Example 1 in that its penetrant comes from Preparation Example 5, and the remaining steps are the same as Example 1.

[0037] Example 7 An immersive quiet PU leather is different from Example 2 in that the amount of penetrant added is 0.1 kg, and the remaining steps are the same as Example 2.

[0038] Example 8 An immersive quiet PU leather is different from Example 2 in that the amount of penetrant added is 0.5 kg, and the remaining steps are the same as Example 2.

[0039] Comparative Example Comparative Example 1 An immersive quiet PU leather is different from Example 2 in that no penetrant is added to its water-based coating layer, and the remaining steps are the same as Example 2.

[0040] Performance testing Detection method / test method Immersive quiet PU leather was prepared according to the preparation methods of Examples 1-8 and Comparative Example 1, and then tested according to the following testing method. The test results are shown in Table 2.

[0041] RPN: Tested according to the test method in VDA 230-206-2005, RPN is a description of the stick-slip tendency, describing the tendency of the material to stick-slip under given conditions. For the treatment of the material pair, the smaller the RPN, the better the sound-absorbing and noise-reducing effect. RPN greater than 6 means that audible noise can be expected; the industry standard for sound-absorbing and noise-reducing PU leather is RPN≤3.

[0042] Dynamic friction coefficient: The lower the dynamic friction coefficient, the less likely it is to generate noise. The detection method refers to the invention patent with application number 201810791678.4.

[0043] Table 2 Test results of Examples 1-8 and Comparative Example 1 It can be seen from Examples 1-8 and Comparative Example 1, as well as the test data in Table 2, that the longitudinal dynamic friction coefficients of the PU leather prepared in the present application are all 0.34 and below, and the lateral dynamic friction coefficients are all 0.35 and below; and through testing, their RPNs are all ≤1, which is far lower than the industry standard; this indicates that the PU leather prepared in the present application has excellent sound-absorbing and noise-reducing performance, and its application potential has been greatly improved.

[0044] Alkyl polyglycoside has low surface tension, good solubility in water, and strong wetting ability. By using alkyl polyglycoside as a penetrant, it can be adsorbed on the surface of the sound-absorbing and noise-reducing additive, promoting the mutual penetration between the organic raw materials and the inorganic raw materials of the water-based coating layer, making the integrity of the water-based coating layer stronger, and greatly reducing the dynamic friction coefficient of the surface of the PU leather, thereby improving its sound-absorbing and noise-reducing performance. It can be seen from the test data of Example 1 and Comparative Example 1.

[0045] However, due to the good foaming property of alkyl polyglycoside, after it is added to the water-based coating layer, the water-based coating layer has rich and delicate foam, which is not conducive to the smoothness of the PU leather surface, and is prone to depression, increasing its surface dynamic friction coefficient. In addition, alkyl polyglycoside has a strong thickening ability. After addition, it leads to poor dispersion ability in the system, and its thickening effect is not conducive to the dispersion of the sound-absorbing and noise-reducing additive. Based on this, by grafting it with a hyperbranched polymer, due to the extremely low viscosity of the hyperbranched polymer and its high solubility in water, its thickening effect can be reduced after grafting; at the same time, it is grafted with a silane coupling agent, and the effect of the organic silicon compound can reduce the foaming of the alkyl polyglycoside. The silane coupling agent can also be coupled with the sound-absorbing and noise-reducing additive, and the penetration effect of the alkyl polyglycoside is mutually promoted; under multiple effects, the affinity between the sound-absorbing and noise-reducing additive and each raw material is greatly promoted, making the integrity of the water-based coating layer stronger, thereby further reducing the dynamic friction coefficient of the PU leather and improving its sound-absorbing and noise-reducing effect. This can be seen from the test data of Example 1 and Example 2.

[0046] It can be seen from the test data of Examples 2-4 that the molecular weight of the carboxyl-terminated hyperbranched polyester is a key factor affecting the permeability of the penetrant, and its molecular weight should not be too low or too high, and the effect is better when it is 2600. Combined with Examples 5-6, the addition amount of the silane coupling agent is preferably in the range of 0.2-0.6 kg. If the silane coupling agent is added too much, the viscosity of the system is easily increased, which is not conducive to the dispersibility of the penetrant and the permeability of the alkyl polyglycoside; if the silane coupling agent is added too little, its coupling effect is weak and the promotion effect is insufficient.

[0047] Based on the best permeation performance of the permeation agent in Example 2, the addition amount of 0.5 kg is a better technical effect, but compared with the addition of 0.3 kg, the optimization effect is smaller. Considering the comprehensive economic cost, the better addition amount is 0.3 kg.

[0048] This specific embodiment is merely an explanation of the present invention and is not a limitation of the present invention. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. An immersive and quiet PU leather, characterized by: The invention comprises a base fabric, one side of the base fabric is bonded with a middle layer through a high peeling force adhesive layer, and the side of the middle layer away from the base fabric layer is coated with a water-based coating layer; the water-based coating layer comprises the following raw materials in parts by weight: 50-90 parts of a matte surface treatment agent, 10-50 parts of a gloss-enhancing surface treatment agent, 5-8 parts of a cross-linking agent, 3-6 parts of an anti-wear agent, 0.5-2 parts of a leveling agent, 0.1-0.5 parts of a penetrant, 0.1-3 parts of a mutual solvent, 3-10 parts of a sound-absorbing and noise-reducing auxiliary agent, and 10-40 parts of water; The noise reduction auxiliary agent is vermiculite, and the penetrant is alkyl polyglycoside.

2. The immersive quiet PU leather according to claim 1, characterized in that: The penetrant is prepared by esterification reaction of alkyl polyglycoside, hydroxy silane coupling agent and carboxyl-terminated hyperbranched polyester, and the preparation method thereof is as follows: Under nitrogen atmosphere, using DMF as solvent, n-butanol as water-carrying agent, and p-toluenesulfonic acid as catalyst, 13-17 parts by weight of terminal carboxyl hyperbranched polyester, 0.4-0.6 parts by weight of alkyl glycoside, and 0.2-0.6 parts by weight of hydroxy silane coupling agent are added, the temperature is raised to 145-155° C., the reaction is stirred, and the solvent is removed to obtain a penetrant.

3. The immersive quiet PU leather according to claim 2, characterized in that: The average molecular weight of the carboxyl-terminated hyperbranched polyester is in the range of 1000-6400.

4. The immersive quiet PU leather according to claim 2, characterized in that: The hydroxysilane coupling agent is 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane.

5. The immersive quiet PU leather according to claim 4, characterized in that: The added amount of the 3-[bis(2-hydroxyethyl)amino]propanetriethoxysilane is 0.4 parts by weight.

6. The immersive quiet PU leather according to claim 2, characterized in that: The added amount of the penetrant is 0.3 parts by weight.

7. The immersive quiet PU leather according to claim 1, characterized in that: The middle layer comprises the following raw materials in parts by weight: 95-100 parts of PU resin, 55-70 parts of DMF, 15-25 parts of ethyl acetate and 7-28 parts of color paste.

8. The immersive quiet PU leather according to claim 1, characterized in that: The high release force adhesive layer comprises the following raw materials in parts by weight: 95-100 parts of solvent-free adhesive material A, 100-110 parts of solvent-free adhesive material B, 0.045-0.1 parts of accelerator, 0.3-0.9 parts of curing agent, 0.25-0.55 parts of leveling agent and 35-55 parts of flame retardant.

9. A method for preparing the immersive quiet PU leather according to any one of claims 1 to 8, characterized in that: It includes the following steps: S1. Mix the raw materials of the middle layer to obtain a middle layer mixture, apply the middle layer mixture on the release paper, heat and dry it to obtain a drying layer; apply the middle layer mixture on the drying layer again, heat and dry it to obtain a middle layer; S2, mixing the raw materials of the high release force adhesive layer to obtain a high release force adhesive layer mixture, applying the high release force adhesive layer mixture to the surface of the middle layer, and then pre-baking it to a semi-dry pasting state, and then laminating it with the base fabric, drying it, and then separating the release paper, the one side of the separated release paper is a PU texture surface, and the applied high release force adhesive layer mixture forms a high release force adhesive layer; S3. Stir and mix the raw materials of the water-based coating layer to obtain a water-based coating layer mixture, apply the mixture to the PU texture surface with a roller, and dry it to obtain an immersive quiet PU leather.

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