Flame-retardant artificial leather and method for producing the same

Abstract

The application relates to a flame-retardant artificial leather and a preparation method thereof, and relates to the field of artificial leather technology. The flame-retardant artificial leather comprises a base cloth layer, a bottom layer and a surface layer which are sequentially attached; the thickness of the surface layer is 0.1-0.3 mm, and the thickness of the bottom layer is 0.3-0.5 mm; the surface layer comprises the following raw materials in parts by weight: 100-120 parts of PVC resin, 60-100 parts of plasticizer, 10-60 parts of flame retardant, 1-5 parts of stabilizer and 1-10 parts of color masterbatch; and the bottom layer comprises the following raw materials in parts by weight: 100-120 parts of PVC resin, 40-90 parts of plasticizer, 10-180 parts of flame retardant, 1-5 parts of stabilizer and 1-10 parts of color masterbatch. The bottom layer and the surface layer formula of the PVC resin layer in the artificial leather are separately designed, the adding amount of the surface layer flame retardant is reduced, the adding amount of the bottom layer flame retardant is increased, the overall flame-retardant effect of the product is kept at a high level, and the aging resistance of the product is effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of artificial leather technology, in particular to a flame-retardant artificial leather and a preparation method thereof. BACKGROUND

[0002] Artificial leather is a plastic product that looks and feels like leather and can replace it. Artificial leather is usually made of fabric as the base, coated with synthetic resin and various plastic additives, mainly including PVC artificial leather and PU artificial leather. Artificial leather can be processed according to different strength, wear resistance, cold resistance, color, gloss, pattern and other requirements, and has the characteristics of various colors, good waterproof performance, neat edges, high utilization rate and relatively low price compared with real leather. Therefore, artificial leather is widely used in the fields of automobiles, furniture, home furnishing, etc.

[0003] Artificial leather itself has the characteristic of not being resistant to fire, especially when used in the fields of automobiles, home furnishing, etc. Artificial leather that is not resistant to fire is easy to be ignited and even cause a fire, bringing great risk to life and property safety. Although PVC resin in PVC artificial leather has certain flame-retardant properties, a large amount of plasticizer is added during the manufacture of artificial leather in order to improve its plasticity, and the addition of plasticizer reduces the chlorine content in PVC resin. In addition, since the base cloth of artificial leather is generally flammable, the flame-retardant performance of conventional PVC artificial leather is poor, which limits its application in places with high flame-retardant requirements.

[0004] In order to improve the flame-retardant performance of artificial leather in the prior art, a certain amount of flame retardant is usually added to the resin layer to inhibit combustion through the effects of heat absorption, covering, chain reaction inhibition, non-flammable gas suffocation, etc. However, the addition of a large amount of flame retardant also causes the aging resistance of artificial leather products to decrease, affecting the durability of the products. SUMMARY

[0005] Based on the above technical problems, the present application provides a flame-retardant artificial leather and a preparation method thereof, in order to improve the flame-retardant effect of artificial leather while improving its aging resistance and improving the durability of the product.

[0006] In a first aspect, the present application provides a flame-retardant artificial leather, which adopts the following technical solution:

[0007] A flame-retardant artificial leather, comprising a base cloth layer, a bottom layer and a surface layer which are sequentially attached; the surface layer has a thickness of 0.1-0.3mm, and the bottom layer has a thickness of 0.3-0.5mm;

[0008] The surface layer comprises the following raw materials by weight: 100-120 parts of PVC resin, 60-100 parts of plasticizer, 10-60 parts of flame retardant, 1-5 parts of stabilizer and 1-10 parts of color masterbatch;

[0009] The bottom layer includes the following raw materials by weight: PVC resin 100-120 parts, plasticizer 40-90 parts, flame retardant 10-180 parts, stabilizer 1-5 parts, color masterbatch 1-10 parts.

[0010] By adopting the technical scheme, the resin layer of the PVC artificial leather in the prior art generally includes two layers, the two layers of resin are designed with the same raw material ratio and are coated separately to obtain higher strength, hand feeling and wear resistance. Since the top layer and the bottom layer are not designed separately, the addition amount of the flame retardant in the top layer of the product is high, although the flame retardation effect meets the requirements, but the overall aging resistance of the product is not good, which affects the durability and service life of the product. In the technical scheme, the formula of the bottom layer and the top layer of the resin layer is designed separately, the addition amount of the flame retardant in the top layer is reduced, and the addition amount of the flame retardant in the bottom layer is increased, so that the overall flame retardation effect of the product is kept at a high level, and the aging resistance is effectively improved. In addition, in the technical scheme, the thickness of the bottom layer is appropriately increased, and the addition amount of the flame retardant in the bottom layer is increased, so that the flame retardation performance of the bottom layer is kept at a high level, and the decrease of the flame retardation performance caused by the decrease of the addition amount of the flame retardant in the top layer is compensated, and then the overall flame retardation performance of the artificial leather is kept at a good level.

[0011] Optionally, the top layer includes the following raw materials by weight: PVC resin 100 parts, plasticizer 60-100 parts, flame retardant 20-45 parts, stabilizer 1-5 parts, color masterbatch 1-10 parts.

[0012] The bottom layer includes the following raw materials by weight: PVC resin 100-120 parts, plasticizer 40-90 parts, flame retardant 60-120 parts, stabilizer 1-5 parts, color masterbatch 1-10 parts.

[0013] By adopting the technical scheme, the addition amount of the flame retardant in the bottom layer is higher than that in the top layer by further limiting the addition amount of the flame retardant in the top layer and the bottom layer, and the thickness of the bottom layer and the top layer is further adapted, so that the overall flame retardation performance of the artificial leather is kept unchanged while the weather resistance is improved.

[0014] Optionally, the flame retardant includes one or more of a phosphorus-nitrogen type flame retardant, a solid-phase flame retardant and a gas-phase flame retardant.

[0015] Optionally, in the top layer, the flame retardant includes: phosphorus-nitrogen type flame retardant 1-20 parts, solid-phase flame retardant 1-30 parts, gas-phase flame retardant 1-10 parts.

[0016] Optionally, in the bottom layer, the flame retardant includes: phosphorus-nitrogen type flame retardant 5-50 parts, solid-phase flame retardant 10-100 parts, gas-phase flame retardant 1-20 parts.

[0017] By adopting the technical scheme, the phosphorus-nitrogen flame retardant, the solid-phase flame retardant and the gas-phase flame retardant are compounded to form a composite flame retardant, the phosphorus-nitrogen flame retardant, the solid-phase flame retardant and the gas-phase flame retardant can inhibit combustion at different parts of the combustion reaction to play a flame-retardant effect, and better flame-retardant effect is achieved. According to the different adjustment of the ratio of various flame retardants in the surface layer and the bottom layer, the flame-retardant performance of the artificial leather product can be better improved. In the combustion reaction process, the solid-phase flame retardant reacts with the polymer to promote the formation of a carbon layer with a shielding property on the surface of the polymer, thereby reducing the release of polymer internal decomposition gas into the environment and reducing the transmission of flame heat to the inside of the polymer, and finally achieving the effect of flame retardation. The gas-phase flame retardant releases phosphorus-containing and other flame-quenching substances into the flame during combustion. These substances form free radical quenchers at high temperatures, quench high-energy radicals in the flame during combustion, and block the chain reaction in the flame during combustion to achieve the effect of flame retardation.

[0018] Optionally, in the surface layer, the mass ratio of the phosphorus-nitrogen flame retardant, the solid-phase flame retardant and the gas-phase flame retardant is (1-20):(1-30):(1-10).

[0019] Optionally, in the bottom layer, the mass ratio of the phosphorus-nitrogen flame retardant, the solid-phase flame retardant and the gas-phase flame retardant is (5-50):(10-100):(1-20).

[0020] By adopting the above technical scheme, the addition amount of various flame retardants is further limited within the above range, and better flame-retardant performance and weather resistance can be obtained.

[0021] Optionally, the solid-phase flame retardant comprises one or more of triphenyl phosphate, melamine and melamine polyphosphate.

[0022] Optionally, the gas-phase flame retardant comprises one or more of brominated imine, decabromodiphenyl ethane and tetrabromobisphenol A.

[0023] By adopting the above technical scheme, by compounding the above gas-phase flame retardant, solid-phase flame retardant and phosphorus-nitrogen flame retardant, the artificial leather prepared has better flame-retardant performance and good weather resistance, and the overall performance of the product can be further improved.

[0024] Optionally, the plasticizer is one or more of phthalate plasticizers, phosphate plasticizers and epoxy plasticizers.

[0025] In a second aspect, the present application provides a preparation method of flame-retardant artificial leather, which adopts the following technical scheme:

[0026] A preparation method of flame-retardant artificial leather, comprising the following steps:

[0027] S1, the raw materials of the surface layer and the bottom layer are respectively weighed according to the proportion and mixed separately to obtain the surface layer glue and the bottom layer glue;

[0028] S2, the bottom layer glue and the surface layer glue are respectively put into the mixing mill for mixing, and then transferred to the open mill for plasticizing after mixing, and then calendered to obtain the bottom layer sheet and the surface layer sheet;

[0029] S3, the bottom layer sheet and the surface layer sheet are sequentially attached to the base cloth, and then foamed and embossed to obtain the flame-retardant artificial leather.

[0030] Optionally, in step S1, the mixing temperature of the surface layer glue is 80-110℃, and the mixing time is 3-5min; the mixing temperature of the bottom layer glue is 100-130℃, and the mixing time is 5-10min.

[0031] Optionally, in step S2, the mixing temperature is 100-150℃, and the plasticizing temperature is 100-150℃.

[0032] Optionally, in the step, the foaming and embossing temperature is 150-200℃.

[0033] By adopting the above technical scheme, the bottom layer and the surface layer of the PVC resin layer are combined by pre-preparing and calendering and then attached to the base cloth, and the surface layer glue and the bottom layer glue are mixed at different temperatures, so that the flame retardant and each component in the raw materials are fully mixed and uniform, the performance of each part of the product after calendering is more uniform, and the overall performance is improved.

[0034] In summary, the present application has at least one of the following beneficial technical effects:

[0035] 1. In the technical scheme of the present application, the formula of the bottom layer and the surface layer of the PVC resin layer in the artificial leather is designed separately, the addition amount of the surface layer flame retardant is reduced, the addition amount of the bottom layer flame retardant is increased, the overall flame retardant effect of the product is maintained at a high level, and the aging resistance is effectively improved; and the thickness of the bottom layer is appropriately increased, and the addition amount of the flame retardant in the bottom layer is increased, so that the flame retardant performance of the bottom layer is maintained at a high level, and the decrease of the flame retardant performance caused by the decrease of the addition amount of the flame retardant in the surface layer is compensated, and the overall flame retardant performance of the artificial leather is maintained at a good level.

[0036] 2. In the technical scheme of the present application, the flame retardant is a gas-phase flame retardant, a solid-phase flame retardant and a phosphorus-nitrogen flame retardant, which are used in a specific ratio, can inhibit the flame at different positions of combustion, form a shielding layer on the surface of the combustion material, and release flame-retardant gas at the same time, so that the overall flame-retardant performance of the artificial leather is further improved. DETAILED DESCRIPTION

[0037] The application will be further described in detail below in connection with specific examples. It should be noted that, in the following examples, if not specified, the conditions are all in accordance with the conventional conditions or the conditions recommended by the manufacturer; and the raw materials used in the following examples can be sourced from the general market, unless otherwise specified. Example

[0038] A flame-retardant artificial leather comprises a base cloth layer, a bottom layer and a surface layer which are sequentially attached, the base cloth layer is a non-woven fabric, the thickness of the bottom layer is 0.4mm, and the thickness of the surface layer is 0.1mm, the raw material ratio of the bottom layer and the surface layer is shown in Table 1, and the specific preparation method is as follows:

[0039] S1, according to the ratio, the surface layer and the bottom layer raw materials are respectively weighed and put into a high-speed mixer for mixing, the surface layer raw material is mixed at 100℃ for 4min, and the bottom layer raw material is mixed at 120℃ for 8min, to obtain the surface layer glue and the bottom layer glue respectively; the mass ratio of phosphorus-nitrogen flame retardant, solid-phase flame retardant and gas-phase flame retardant in the flame retardant is 1:1:1;

[0040] S2, the bottom layer glue and the surface layer glue are respectively put into a mixing mill for mixing at 120℃, and then transferred to an open mill for plasticizing at 130℃, and then conveyed to a calender for calendering, to obtain the bottom layer sheet and the surface layer sheet respectively; the mass ratio of phosphorus-nitrogen flame retardant, solid-phase flame retardant and gas-phase flame retardant in the flame retardant is 1:1:1;

[0041] S3, the bottom layer sheet and the surface layer sheet are sequentially attached to the base cloth, and then conveyed to a foaming embossing machine for foaming embossing treatment at 180℃, to obtain the flame-retardant artificial leather.

[0042] Among them, the phosphorus-nitrogen flame retardant is ammonium polyphosphate, the solid-phase flame retardant is melamine, and the gas-phase flame retardant is brominated imine. Example

[0043] The difference between this example and Example 1 is that the raw material component ratio is different, and the specific reference is shown in Table 1, and the rest is consistent with Example 1. Example

[0044] The difference between this example and Example 1 is that the raw material component ratio is different, and the specific reference is shown in Table 1, and the rest is consistent with Example 1.

[0045] Table 1: Raw material component ratio of Examples 1-3 (unit: kg)

[0046]

[0047] The difference between this example and Example 3 is that the addition amount of the flame retardant in the surface layer is 120kg, and the addition amount of the flame retardant in the bottom layer is 60kg, and the rest is consistent with Example 3.

[0048] The difference between the present comparative example and Example 3 is that the addition amount of the flame retardant in the surface layer is 120 kg, and the rest is consistent with Example 3.

[0049] The difference between the present comparative example and Example 3 is that the thickness of the bottom layer and the surface layer is 0.1 mm, and the rest is consistent with Example 3.

[0050] The difference between the present comparative example and Example 3 is that the thickness of the surface layer is 0.5 mm, and the rest is consistent with Example 3.

[0051] The flame-retardant artificial leather prepared in the examples and comparative examples is subjected to performance detection, and the specific methods are as follows:

[0052] Mechanical properties: The tensile strength of the sample is detected according to QB / T 2710-2018; the peel strength of the sample is detected according to GB / T 8808-1988, and the sample size is A method, the sample width is 15 mm, and the length is 200 mm.

[0053] Flame-retardant properties: The limiting oxygen index of the sample during combustion is detected according to ASTM D 2863-2000, and the sample type is II.

[0054] Aging resistance: The elongation retention rate of the sample is tested after the sample is continuously irradiated under 40 W ultraviolet light for 2500 h.

[0055] The performance detection results of Examples 1-3 and Comparative Examples 1-4 are shown in Table 2 below.

[0056] Table 2: Performance detection results of Examples 1-3 and Comparative Examples 1-4

[0057]

[0058] As can be seen from the data in Table 2, by separately designing the bottom layer and the surface layer, appropriately reducing the addition amount of the flame retardant in the surface layer and increasing the addition amount of the flame retardant in the bottom layer, the aging resistance of the overall product is obviously improved while the flame-retardant effect meets the requirements. As can be seen from the data in Examples 3 and Comparative Examples 1-4, too high addition amount of the flame retardant in the surface layer will obviously affect the aging resistance of the overall product, and the change in the thickness of the surface layer and the bottom layer will also cause changes in the flame-retardant and aging-resistant properties of the artificial leather product.

[0059] The difference between the present example and Example 3 is that the mass ratio of the phosphorus-nitrogen flame retardant, the solid-phase flame retardant and the gas-phase flame retardant in the surface layer and the bottom layer is 1:2:1, and the rest is consistent with Example 3.

[0060] The difference between the present example and example 3 is that the mass ratio of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant in the surface layer is 2:4:1, the mass ratio of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant in the bottom layer is 3:6:1, and the rest is consistent with example 3.

[0061] The difference between the present example and example 3 is that the mass ratio of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant in the surface layer is 1:2:4, the mass ratio of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant in the bottom layer is 1:3:3, and the rest is consistent with example 3.

[0062] The difference between the present example and example 3 is that the mass ratio of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant in the surface layer is 4:1:4, the mass ratio of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant in the bottom layer is 6:1:3, and the rest is consistent with example 3.

[0063] The difference between the present example and example 3 is that the mixing temperature of the surface layer compound is 120℃, and the mixing time is 5min; the mixing temperature of the bottom layer compound is 90℃, and the mixing time is 3min, and the rest is consistent with example 3.

[0064] The performance detection results of examples 4-8 are shown in table 3 below.

[0065] Table 3: Performance detection results of examples 4-8

[0066]

[0067] From the data in table 3, it can be seen that the ratio of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant in the flame retardant has a great influence on the flame retardation and aging resistance of the artificial leather. Specifically, when the three components of phosphorus-nitrogen type flame retardant, solid-phase flame retardant and gas-phase flame retardant are within the range defined in the technical scheme of the present application, the flame retardation and aging resistance of the artificial leather can reach a high level, and when the ratio of the three components is changed, the flame retardation and aging resistance of the artificial leather both decrease obviously, especially when the component ratio of the flame retardant in the surface layer is changed. In example 7, the addition amount of solid-phase flame retardant in the surface layer and the bottom layer is reduced, and although the flame retardation of the artificial leather does not decrease obviously, its aging resistance changes greatly.

[0068] In Example 8, the temperature and mixing time of the surface coating compound and the bottom layer compound during the preparation of the flame-retardant artificial leather are adjusted. When the temperature and mixing time of the surface coating compound are increased and the temperature and mixing time of the bottom layer compound are decreased, the flame-retardant performance and aging resistance of the flame-retardant artificial leather product are both decreased to a certain extent. This may be caused by the incompatibility between the mixing temperature and mixing time of the compound and the component ratio of the raw materials, especially the uneven mixing of the bottom layer compound, which leads to the decrease of the flame-retardant performance.

[0069] The above are preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, any equivalent changes made on the basis of the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A flame-retardant artificial leather, characterized by, The invention discloses a flame-retardant artificial leather, which comprises a base cloth layer, a bottom layer and a surface layer which are sequentially attached; the thickness of the surface layer is 0.1-0.3mm, and the thickness of the bottom layer is 0.3-0.5mm; the surface layer comprises the following raw materials in parts by weight: PVC resin 100 parts, plasticizer 60-100 parts, flame retardant 20-30 parts, stabilizer 1-3 parts and color masterbatch 1-10 parts; the bottom layer comprises the following raw materials in parts by weight: PVC resin 100-120 parts, plasticizer 60-90 parts, flame retardant 100-120 parts, stabilizer 1-3 parts and color masterbatch 1-10 parts; the surface layer flame retardant is ammonium polyphosphate, melamine and brominated imine with a mass ratio of 2:4:1; and the bottom layer flame retardant is ammonium polyphosphate, melamine and brominated imine with a mass ratio of 3:6:

1.

2. A process for the production of a flame-retardant artificial leather according to any one of claims 1, characterized in that, The invention discloses a method for preparing the flame-retardant artificial leather, which comprises the following steps: S1, raw materials of the surface layer and the bottom layer are respectively weighed according to the proportion and mixed separately to prepare surface layer glue and bottom layer glue; S2, the bottom layer glue and the surface layer glue are respectively put into a mixing mill for mixing, and then transferred to an open mill for plasticizing after mixing; after plasticizing, the bottom layer sheet and the surface layer sheet are obtained by calendering; S3, the bottom layer sheet and the surface layer sheet are sequentially attached to the base cloth, and then foaming and embossing are performed to obtain the flame-retardant artificial leather.

3. A process for the preparation of a flame-retardant artificial leather according to claim 2, characterized in that, In step S1, the mixing temperature of the surface layer glue is 80-110℃, and the mixing time is 3-5min; the mixing temperature of the bottom layer glue is 100-130℃, and the mixing time is 5-10min.

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