A flame retardant synergist for water-based coatings and its preparation method and application

Abstract

The present invention discloses a flame retardant synergist for water-based paint, a preparation method and application thereof, wherein the raw materials for preparation include: a zirconium source, an organic ligand and a phosphorus source; the organic ligand includes at least one of terephthalic acid and aminoterephthalic acid; and the phosphorus source includes phytic acid. The flame retardant synergist for water-based paint proposed by the present invention has excellent transparency, can perfectly retain and highlight the natural texture and color of wood, and has excellent flame retardant properties, can rapidly expand when heated to form a solid heat insulation layer, and mitigate the impact of fire.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a flame retardant synergist for water-based coatings, a preparation method and an application thereof. Background Art

[0002] Paint is a substance applied to the surface of an object for the protection, decoration and certain properties of the coated object. With the acceleration of the global industrialization process, environmental problems are becoming increasingly severe, and environmental protection has become a consensus. In the coatings industry, traditional solvent-based coatings have caused serious pollution to the atmospheric environment due to their high volatile organic compounds (VOCs) emissions. VOCs are not only harmful to human health, but also one of the main causes of photochemical smog and ozone layer depletion. Therefore, the development of environmentally friendly coatings, especially water-based coatings with low or even no VOCs emissions, has become an inevitable choice for the transformation and upgrading of the coatings industry. As a widely used building material and raw material for furniture manufacturing, the flammability of wood has become a major challenge in the field of fire safety. In order to improve the flame retardant properties of wood products and reduce the risk of fire, it is particularly important to develop high-performance water-based flame retardant coatings. This type of coating can effectively slow down the spread of fire when a fire occurs, buying valuable time for personnel evacuation and fire rescue. Therefore, the research and development of high-performance water-based flame-retardant coatings is of great significance. It is not only an inevitable trend of green development in the coatings industry, but also an important way to improve the safety performance of wood products. As an important member of the field of modern environmentally friendly coatings, water-based intumescent flame-retardant coatings have received extensive attention and research in recent years. However, while improving the flame retardant performance, water-based intumescent wood flame-retardant coatings often affect their transparency. How to ensure that the coating has good flame retardant properties while maintaining its high transparency is a major challenge facing current technology. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention proposes a flame retardant synergist for water-based coatings, and the coating prepared by the present invention not only has excellent transparency, can perfectly preserve and highlight the natural texture and color of wood, but also has excellent flame retardant properties, can quickly expand when heated to form a solid heat insulation layer, and reduce the impact of fire.

[0004] The present invention also provides an intumescent flame retardant, wherein the raw materials for preparing the intumescent flame retardant include the flame retardant synergist.

[0005] The present invention also provides a water-based flame-retardant coating, wherein the raw materials for preparing the water-based flame-retardant coating include the intumescent flame retardant.

[0006] The first aspect of the present invention provides a flame retardant synergist for water-based coatings, the preparation raw materials including: a zirconium source, an organic ligand and a phosphorus source;

[0007] The organic ligand comprises at least one of terephthalic acid and aminoterephthalic acid;

[0008] The phosphorus source includes phytic acid.

[0009] The zirconium source reacts with terephthalic acid to form MOF, which itself has flame retardant properties. After adding phytic acid, on the one hand, the catalytic carbonization of MOF is brought into play, promoting condensed phase flame retardancy. On the other hand, the presence of phytic acid ligands can greatly increase phosphorus free radicals, play a role in capturing gas phase free radicals, and promote the release of inert gases during combustion, achieving gas phase flame retardancy. Phytic acid has a high phosphorus content and contains 6 negatively charged phosphate groups, which give phytic acid excellent flame retardant properties. At the same time, phytic acid can coordinate with metal ions. This material can catalyze the rapid carbonization of the substrate during the combustion process, forming a more stable and effective carbon layer protective layer.

[0010] The phosphorus-containing UiO-66 flame retardant synergist of the present invention can be used for water-based flame retardant coatings, so that the coatings have high transparency and excellent flame retardant properties.

[0011] In some embodiments of the present invention, the method for preparing the flame retardant synergist for water-based coatings comprises: mixing and dispersing a zirconium source, an organic ligand and a phosphorus source, and then ball milling and removing impurities.

[0012] In some embodiments of the present invention, the dispersing step includes adding a dispersant.

[0013] In some embodiments of the present invention, the dispersant comprises ethanol, methanol or acetone.

[0014] In some embodiments of the present invention, the amount of the dispersant added is 0.5 to 1.5 ml of dispersant per gram of reaction raw material.

[0015] In some embodiments of the present invention, the rotation speed of the ball mill is 900-1200 r / min.

[0016] In some embodiments of the present invention, the ball milling time is 10 to 40 minutes.

[0017] In some embodiments of the present invention, the step of removing impurities includes washing and then drying.

[0018] In some embodiments of the present invention, the drying temperature is 140-180°C.

[0019] In some embodiments of the present invention, the drying time is 5 to 8 hours.

[0020] In some embodiments of the present invention, the molar ratio of the zirconium source, the organic ligand and the phosphorus source is 2-4:2-4:1.

[0021] The invention adopts a mechanochemical method to synthesize a phosphorus-containing UiO-66 flame retardant synergist by coordinating zirconium metal ions with phytic acid. The method has the advantages of simple operation, environmental protection, energy saving, high efficiency and rapidity.

[0022] In some embodiments of the present invention, the raw materials for preparing the intumescent flame retardant include a flame retardant synergist.

[0023] In some embodiments of the present invention, the raw materials for preparing the intumescent flame retardant further include: silane-modified ammonium polyphosphate and a char-forming flame retardant aid.

[0024] In some embodiments of the present invention, the amount ratio of the flame retardant synergist, the silane-modified ammonium polyphosphate and the char-forming flame retardant aid is 3 to 1:5 to 3:1.

[0025] In some embodiments of the present invention, the method for preparing the intumescent flame retardant comprises: mixing and ball-milling the flame retardant synergist, the silane-modified ammonium polyphosphate and the char-forming flame retardant aid to obtain the intumescent flame retardant.

[0026] The silane-modified ammonium polyphosphate used in the present invention is different from conventional polyphosphate amines and has a higher degree of polymerization, so it has a better carbon-forming effect. The silane-modified ammonium polyphosphate is modified by surface treatment and can have good compatibility with water-based resins. The transparent carbon-forming flame retardant auxiliary agent used in the present invention has both carbon-forming and acid-source flame-retardant functional auxiliary agents, has excellent carbon-forming performance, and has good compatibility with water-based resins after ball milling ultrafine treatment. The dispersibility and compatibility of flame retardants in water-based resins are improved by surface treatment technology. By means of fine ball milling, surface modification and the like, the flame retardant particles are evenly dispersed in the resin to avoid agglomeration, thereby maintaining the transparency of the coating.

[0027] The composition of intumescent flame retardants mainly includes three basic elements: acid source (also called dehydrating agent or carbonization accelerator), carbon source (also called carbonizing agent) and gas source (also called foaming source). These components each play an important role in the flame retardant process and work together to achieve efficient flame retardant effect. Ammonium polyphosphate is an acid source, which is a key part of the flame retardant system. Its main function is to promote and change the thermal decomposition process of the matrix polymer. It can release inorganic acids (such as phosphoric acid) at the beginning of combustion. These acids can act as dehydrating agents to promote the carbonization of the substrate and form a three-dimensional carbon layer that is not easy to burn. At the same time, the acid source can also reduce the combustible tar and low-molecular combustibles produced by thermal decomposition, thereby enhancing the flame retardant effect. The silicon and phosphorus elements in silane-modified ammonium polyphosphate can produce a synergistic effect during the combustion process. The phosphorus element can promote the dehydration and carbonization reaction of the substrate, while the silicon element can enhance the stability of the carbon layer by forming a silicon-containing protective layer. Ammonium polyphosphate with a high degree of polymerization can more efficiently promote the carbonization reaction of the substrate during combustion. Longer molecular chains and more cross-linking points enable the ammonium polyphosphate molecules to better bond with the substrate, forming a more stable and denser carbon layer.

[0028] In some embodiments of the present invention, the rotation speed of the ball mill is 900-1200 r / min, and the time of the ball mill is 5-20 min.

[0029] In some embodiments of the present invention, the raw materials for preparing the water-based flame retardant coating include an intumescent flame retardant.

[0030] In some embodiments of the present invention, the raw materials for preparing the water-based flame retardant coating further include water-based acrylic emulsion, intumescent flame retardant, film-forming aid, defoamer, thickener and wetting agent.

[0031] In some embodiments of the present invention, the raw materials for preparing the water-based flame retardant coating include, by weight, 55-75 parts of water-based acrylic emulsion, 15-35 parts of intumescent flame retardant, 2-6 parts of film-forming aid, 0.1-0.3 parts of defoaming agent, 0.1-1 parts of thickener and 0.1-0.5 parts of wetting agent.

[0032] The present invention selects a flame retardant with high flame retardant performance and little effect on the transparency of the coating. At the same time, the dispersibility and compatibility of the flame retardant in the water-based resin are improved. Through fine ball milling, the flame retardant particles are evenly dispersed in the resin, thereby maintaining the transparency of the coating, and then the phosphorus-containing UiO-66 flame retardant synergist, silane-modified ammonium polyphosphate and transparent carbon-forming flame retardant additive are put into a stainless steel ball mill for ball milling to obtain an intumescent flame retardant. Finally, it is applied to a water-based flame retardant coating, which not only has excellent transparency, can perfectly retain and highlight the natural texture and color of the wood, but also has excellent flame retardant properties, can rapidly expand when heated to form a solid insulation layer, and mitigate the impact of the fire. DETAILED DESCRIPTION

[0033] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0034] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0035] Unless otherwise specified, "room temperature" in the present invention means 25°C±5°C.

[0036] Unless otherwise specified, "about" in the present invention means that the allowable error is within ±2%.

[0037] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0038] The first aspect of the present invention provides a flame retardant synergist for water-based coatings, the preparation raw materials comprising: a zirconium source, an organic ligand and a phosphorus source;

[0039] The organic ligand comprises at least one of terephthalic acid and aminoterephthalic acid;

[0040] The phosphorus source includes phytic acid.

[0041] Combined with the first aspect, the zirconium source reacts with terephthalic acid to generate MOF, which itself has flame retardant properties. After adding phytic acid, on the one hand, the catalytic carbonization of MOF is exerted to promote condensed phase flame retardancy. On the other hand, the presence of phytic acid ligands can greatly increase phosphorus free radicals, play a role in capturing gas phase free radicals, and promote the release of inert gases during combustion to achieve gas phase flame retardancy. Phytic acid has a high phosphorus content and contains 6 negatively charged phosphate groups, which give phytic acid excellent flame retardant properties. At the same time, phytic acid can coordinate with metal ions. This material can catalyze the rapid carbonization of the substrate during the combustion process to form a more stable and effective carbon layer protective layer.

[0042] A second aspect of the present invention provides an intumescent flame retardant, wherein the raw materials for preparing the intumescent flame retardant include the flame retardant synergist.

[0043] A third aspect of the present invention provides a water-based flame-retardant coating, wherein the raw materials for preparing the water-based flame-retardant coating include the intumescent flame retardant.

[0044] The present invention selects a flame retardant with high flame retardant performance and little effect on the transparency of the coating. At the same time, the dispersibility and compatibility of the flame retardant in the water-based resin are improved. Through fine ball milling, the flame retardant particles are evenly dispersed in the resin, thereby maintaining the transparency of the coating, and then the phosphorus-containing UiO-66 flame retardant synergist, silane-modified ammonium polyphosphate and transparent carbon-forming flame retardant additive are put into a stainless steel ball mill for ball milling to obtain an intumescent flame retardant. Finally, it is applied to a water-based flame retardant coating, which not only has excellent transparency, can perfectly retain and highlight the natural texture and color of the wood, but also has excellent flame retardant properties, can rapidly expand when heated to form a solid insulation layer, and mitigate the impact of the fire.

[0045] Example 1

[0046] This embodiment prepares a flame retardant synergist for water-based coatings, and the specific steps are as follows:

[0047] Zirconium chloride, terephthalic acid and phytic acid (the molar ratio of the three substances is 3:3:1) are placed in a stainless steel ball mill, ethanol is added dropwise at a ratio of 1.3 mL / g, stainless steel ball mill beads are added, the mixture is placed in a QM-3C high-speed vibration ball mill, and then ball milled at 1100 r / min for 30 min to obtain a solid powder; the solid powder is washed with ethanol and vacuum dried to obtain a phosphorus-containing UiO-66 flame retardant synergist.

[0048] This embodiment also prepares an intumescent flame retardant, and the specific steps are:

[0049] The phosphorus-containing UiO-66 flame retardant synergist, silane-modified ammonium polyphosphate FR-AP1001G and transparent carbon-forming flame retardant additive CFA-T (the mass ratio of the three is 3:4:1) are placed in a stainless steel ball mill, stainless steel ball milling beads are added, and placed in a high-speed vibration ball mill. Then the speed of the ball mill is set to 1200r / min, and ball milling is carried out for 20 minutes to obtain an intumescent flame retardant.

[0050] This embodiment also prepares a water-based flame retardant coating, and the specific steps are:

[0051] The following components are included by weight: 60 parts of water-based acrylic emulsion, 35 parts of intumescent flame retardant, 2 parts of film-forming aid propylene (glycol butyl ether), 0.2 parts of defoaming agent (TEGO-815), 0.3 parts of thickener (TT-935), 0.5 parts of wetting agent (TEGO-500) and 2 parts of deionized water.

[0052] The intumescent flame retardant is added to the water-based acrylic emulsion, and then the film-forming aid, defoamer, thickener, water and wetting agent are added in sequence, dispersed for 10-30 minutes, and the material is filtered to obtain a water-based ultra-thin wood flame retardant coating.

[0053] Example 2

[0054] This embodiment prepares a flame retardant synergist for water-based coatings, and the specific steps are as follows:

[0055] Zirconium chloride, terephthalic acid and phytic acid (the molar ratio of the three substances is 3:3:1) are placed in a stainless steel ball mill, ethanol is added dropwise at a ratio of 1.3 mL / g, stainless steel ball milling beads are added, the mixture is placed in a high-speed vibration ball mill, and then ball milled at 1000 r / min for 20 min to obtain a solid powder; the solid powder is washed with ethanol and vacuum dried to obtain a phosphorus-containing UiO-66 flame retardant synergist.

[0056] This embodiment also prepares an intumescent flame retardant, and the specific steps are:

[0057] The phosphorus-containing UiO-66 flame retardant synergist, silane-modified ammonium polyphosphate FR-AP1001G and transparent carbon-forming flame retardant additive CFA-T (the mass ratio of the three is 3:2:1) are placed in a stainless steel ball mill, stainless steel ball milling beads are added, and placed in a high-speed vibration ball mill. The speed of the ball mill is set to 900r / min, and ball milling is carried out for 10 minutes to obtain an intumescent flame retardant.

[0058] This embodiment also prepares a water-based flame retardant coating, and the specific steps are:

[0059] The composition comprises the following components by weight: 70 parts of water-based acrylic emulsion, 25 parts of intumescent flame retardant, 2 parts of film-forming aid, 0.2 parts of defoaming agent, 0.3 parts of thickener, 0.5 parts of wetting agent and 2 parts of deionized water.

[0060] The intumescent flame retardant is added to the water-based acrylic emulsion, and then the film-forming aid, defoamer, thickener, water and wetting agent are added in sequence, dispersed for 10-30 minutes, and the material is filtered to obtain a water-based ultra-thin wood flame retardant coating.

[0061] Example 3

[0062] This embodiment prepares a flame retardant synergist for water-based coatings, and the specific steps are as follows:

[0063] Preparation of phosphorus-containing UiO-66 flame retardant synergist: zirconium chloride, terephthalic acid and phytic acid (the molar ratio of the three substances is 3:3:1) are placed in a stainless steel ball mill, ethanol is added dropwise at a ratio of 1.0 mL / g, stainless steel ball mill beads are added, and the mixture is placed in a high-speed vibration ball mill, and then ball milled at 900 r / min for 20 minutes to obtain a solid powder; the solid powder is washed with ethanol and vacuum dried to obtain a phosphorus-containing UiO-66 flame retardant synergist.

[0064] This embodiment also prepares an intumescent flame retardant, and the specific steps are:

[0065] The phosphorus-containing UiO-66 flame retardant synergist, silane-modified ammonium polyphosphate FR-AP1001G and transparent carbon-forming flame retardant additive CFA-T (the mass ratio of the three is 3:2:1) are placed in a stainless steel ball mill, stainless steel ball milling beads are added, and placed in a high-speed vibration ball mill. The speed of the ball mill is set to 900r / min, and ball milling is carried out for 10 minutes to obtain an intumescent flame retardant.

[0066] This embodiment also prepares a water-based flame retardant coating, and the specific steps are:

[0067] The composition comprises the following components in parts by weight: 75 parts of aqueous acrylic emulsion, 20 parts of intumescent flame retardant, 2 parts of film-forming aid, 0.2 parts of defoaming agent, 0.3 parts of thickener, 0.5 parts of wetting agent and 2 parts of deionized water.

[0068] The intumescent flame retardant is added to the water-based acrylic emulsion, and then the film-forming aid, defoamer, thickener, water and wetting agent are added in sequence, dispersed for 10-30 minutes, and the material is filtered to obtain a water-based ultra-thin wood flame retardant coating.

[0069] Comparative Example 1

[0070] The difference between this comparative example and Example 1 is that no phosphorus-containing UiO-66 flame retardant synergist is added during the preparation of the intumescent flame retardant.

[0071] Comparative Example 2

[0072] The difference between this comparative example and Example 2 is that no phosphorus-containing UiO-66 flame retardant synergist is added during the preparation of the intumescent flame retardant.

[0073] Comparative Example 3

[0074] The difference between this comparative example and Example 3 is that no phosphorus-containing UiO-66 flame retardant synergist is added during the preparation of the intumescent flame retardant.

[0075] Comparative Example 4

[0076] The difference between this comparative example and Example 1 is that phosphoric acid is used instead of phytic acid, and the other conditions are the same.

[0077] Comparative Example 5

[0078] The difference between this comparative example and Example 1 is that dipentaerythritol is used to replace the transparent char-forming flame retardant additive, and the other conditions are the same.

[0079] Comparative Example 6

[0080] The difference between this comparative example and Example 1 is that conventional ammonium polyphosphate is used instead of silane-modified ammonium polyphosphate, and the other conditions are the same.

[0081] Comparative Example 7

[0082] The difference between this comparative example and Example 1 lies in zirconium chloride, terephthalic acid and phytic acid (the molar ratio of the three is 1:3:1), and the other conditions are the same.

[0083] Test Example 1

[0084] The water-based flame retardant coating obtained in the embodiment and the comparative example was applied on the surface of a 200mmX300mmX5mm wooden board (sample) with a dry film thickness of about 0.2mm, and then a butane spray gun was used to burn the coating for 30s for qualitative evaluation. The light transmittance of the coating was tested using a light transmittance meter, the limiting oxygen index was tested using an oxygen index tester, and the test methods for the remaining test items were referred to GB / T 12441-2018 "Decoration Fire Retardant Coatings", and the results are shown in Table 1.

[0085] Table 1 Performance test results of water-based flame retardant coatings of Examples 1-3 and Comparative Examples 1-7

[0086]

[0087]

[0088] As can be seen from Table 1, the addition of phosphorus-containing UiO-66 flame retardant synergist is conducive to improving the expansion and integrity of the carbon layer. The carbon layer formed by heating the wood surface can block the spread of flames and the transfer of heat, thereby improving the flame retardancy of the wood. Among them, the water-based flame retardant coating obtained in Example 1 not only has a high light transmittance, but also can ensure that the natural texture and color of the wood are fully displayed. At the same time, the limiting oxygen index is 45%, which belongs to the flame retardant level, indicating that the flame retardant synergist of the present invention can be used in water-based flame retardant coatings. It can well play the heat insulation and oxygen isolation effect of the expansion type flame retardant system, and has good fire retardant properties. Therefore, the present invention has developed a water-based flame retardant coating that integrates high performance, environmental protection, transparency and flame retardancy. The coating will be widely used in the fields of furniture, floors, doors and windows and other wood products to meet the market's urgent demand for safe, beautiful and environmentally friendly coatings.

[0089] In Comparative Example 4, phosphoric acid is used instead of phytic acid, which results in the inability to form a phosphorus-containing UiO-66 flame retardant synergist, and lacks sufficient expansion and carbonization properties during combustion, resulting in a decrease in the expansion ratio and the limiting oxygen index.

[0090] In Comparative Example 5, dipentaerythritol seriously affects the transparency of the coating, resulting in a decrease in light transmittance. At the same time, it has poor compatibility with the water-based resin, thereby affecting the expansion ratio and limiting oxygen index of the coating.

[0091] In Comparative Example 6, conventional ammonium polyphosphate is used to replace silane-modified ammonium polyphosphate. Conventional ammonium polyphosphate does not have a higher degree of polymerization and therefore does not have a better carbon-forming effect, thereby affecting the expansion ratio and limiting oxygen index of the coating.

[0092] In comparative example 7, the flame retardant synergist prepared by the ratio of the amount of zirconium source, organic ligand and other substances of phosphorus source has an incomplete crystal structure, which makes it unable to fully exert its catalytic carbonization effect, thereby reducing the expansion ratio and limiting oxygen index performance of its coating.

[0093] The above is a detailed description of the embodiments of the present invention, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. A flame retardant synergist for water-based coatings, characterized in that: The preparation raw materials include: a zirconium source, an organic ligand and a phosphorus source; The organic ligand comprises at least one of terephthalic acid and aminoterephthalic acid; The phosphorus source includes phytic acid.

2. The flame retardant synergist for water-based coatings according to claim 1, characterized in that: The amount ratio of the zirconium source, the organic ligand and the phosphorus source is 4-2:4-2:

1.

3. An intumescent flame retardant, characterized in that: The raw materials for preparing the intumescent flame retardant include the flame retardant synergist according to claim 1 or 2.

4. The intumescent flame retardant according to claim 3, characterized in that The raw materials for preparing the intumescent flame retardant further include: silane-modified ammonium polyphosphate and a char-forming flame retardant auxiliary agent.

5. The intumescent flame retardant according to claim 4, characterized in that The amount ratio of the flame retardant synergist, the silane-modified ammonium polyphosphate and the char-forming flame retardant auxiliary agent is 3 to 1:5 to 3:

1.

6. The intumescent flame retardant according to claim 4, characterized in that The preparation method of the intumescent flame retardant comprises: mixing and ball-milling the flame retardant synergist, the silane-modified ammonium polyphosphate and the char-forming flame retardant auxiliary agent to obtain the intumescent flame retardant.

7. The intumescent flame retardant according to claim 6, characterized in that The rotation speed of the ball mill is 900-1200 r / min, and the time of the ball mill is 5-20 min.

8. A water-based flame retardant coating, characterized in that: The raw materials for preparing the water-based flame-retardant coating include the intumescent flame retardant according to any one of claims 3 to 7.

9. The water-based flame-retardant coating according to claim 8, characterized in that: The raw materials for preparing the water-based flame-retardant coating also include water-based acrylic emulsion, intumescent flame retardant, film-forming aid, defoamer, thickener and wetting agent.

10. The water-based flame-retardant coating according to claim 9, characterized in that: By weight, the raw materials for preparing the water-based flame retardant coating include 55-75 parts of water-based acrylic emulsion, 15-35 parts of intumescent flame retardant, 2-6 parts of film-forming aid, 0.1-0.3 parts of defoaming agent, 0.1-1 parts of thickener and 0.1-0.5 parts of wetting agent.

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