阅读说明：本技术 一种pu透明底漆及其制备方法与应用 (PU transparent primer and preparation method and application thereof ) 是由 程亚明 方学平 邱纳新 于 2021-07-15 设计创作，主要内容包括：本发明公开了一种PU透明底漆及其制备方法与应用。所述PU透明底漆包括主剂、固化剂和稀释剂,其中,所述主剂的制备原料包括净味醇酸树脂、醋酸丁酯、脂肪酸锌粉、颗粒粉、防沉浆半成品和VAGH液半成品。本发明方案的底漆中含有主剂、固化剂和稀释剂,直接将三者充分搅拌均匀后,即可进行底漆涂装,使用简单方便且适用性强。具有净味、高柔韧性、抗开裂、高透明性、打磨性、填充性好、让木皮装饰面不易色变、褪色、防下陷性等优点,尤其适用于乌金木制品的制备。(The invention discloses a PU transparent primer and a preparation method and application thereof. The PU transparent primer comprises a main agent, a curing agent and a diluent, wherein the main agent is prepared from raw materials including odor-purifying alkyd resin, butyl acetate, fatty acid zinc powder, particle powder, an anti-settling slurry semi-finished product and a VAGH liquid semi-finished product. The primer of the scheme of the invention contains the main agent, the curing agent and the diluent, and can be used for primer coating after the main agent, the curing agent and the diluent are directly and fully stirred uniformly, so that the primer is simple and convenient to use and has strong applicability. The wood veneer has the advantages of being odorless, high in flexibility, cracking resistance, transparency, polishing performance, good in filling performance, and the like, and the wood veneer decorative surface is not prone to color change, color fading and sinking resistance, and is particularly suitable for preparation of the black gold wood products.)

1. A PU transparent priming paint is characterized in that: the main agent comprises a main agent, a curing agent and a diluent, wherein the main agent is prepared from raw materials including odor-removing alkyd resin, butyl acetate, fatty acid zinc powder, granular powder, an anti-settling slurry semi-finished product and a VAGH liquid semi-finished product; preferably, in the main agent, the mass part ratio of the odor-purifying alkyd resin, the butyl acetate, the fatty acid zinc powder, the granular powder, the anti-settling slurry semi-finished product and the VAGH liquid semi-finished product is 62-84: 5-10: 1-5: 3-8: 2-6.

2. The PU clear primer according to claim 1, wherein: the odor-removing alkyd resin is modified odor-removing alkyd resin; preferably, the modified neat acid resin consists of a monobasic acid; more preferably, the modified neat alkyd resin is selected from modified neat alkyd resins from the company pasteur a 1428-68; preferably, the fatty acid zinc powder is zinc stearate powder; preferably, the granular powder is a sand flour.

3. The PU clear primer according to claim 1, wherein: the anti-settling semi-finished product comprises odor-removing alkyd resin, butyl acetate, bentonite and polyamide wax pulp; preferably, the polyamide wax slurry is modified polyethylene micropowder wax slurry; more preferably, the bentonite is an organobentonite; further preferably, in the anti-settling semi-finished product, the ratio of the odor-removing alkyd resin, the butyl acetate, the bentonite and the polyamide wax pulp in parts by weight is 40-60: 20-30: 5-10: 10-20.

4. The PU clear primer according to claim 1, wherein: the VAGH liquid semi-finished product comprises VAGH, methyl isobutyl ketone, propylene glycol monomethyl ether acetate and butyl acetate; preferably, in the VAGH liquid semi-finished product, the ratio of the parts by weight of VAGH, methyl isobutyl ketone, propylene glycol methyl ether acetate and butyl acetate is 20-40: 10-20: 20-30: 20-40.

5. The PU clear primer according to claim 1, wherein: the preparation raw material of the main agent also comprises a dispersant; preferably a polymeric dispersant; preferably, the preparation raw material of the main agent also comprises a defoaming agent; more preferably, the defoamer is a foam breaking polymer and/or a polysiloxane solution; preferably, the preparation raw materials of the main agent further comprise a leveling agent; more preferably, the leveling agent is polyether modified polydimethylsiloxane.

6. The PU clear primer according to claim 1, wherein: the raw materials for preparing the curing agent comprise butyl acetate, aliphatic polyisocyanate and isocyanate prepolymer; preferably, the aliphatic polyisocyanate is HDI trimer; preferably, the isocyanate prepolymer is hexamethylene diisocyanate based polyisocyanate; more preferably, in the curing agent, the ratio of the butyl acetate to the HDI trimer to the isocyanate prepolymer in parts by mass is 40-60: 15-25: 20-40.

7. The PU clear primer according to claim 1, wherein: the diluent is a non-reactive diluent; preferably, the diluent is prepared from butyl acetate, propylene glycol methyl ether acetate, cyclohexanone and dimethyl carbonate; more preferably, in the diluent, the mass part ratio of butyl acetate, propylene glycol methyl ether acetate, cyclohexanone and dimethyl carbonate is 35-55: 35-45: 2-5: 13-20.

8. The PU clear primer according to any one of claims 1 to 7, wherein: the PU transparent primer comprises 100 parts by mass of a main agent, 40-50 parts by mass of a curing agent and 60-100 parts by mass of a diluent; preferably, the PU transparent primer comprises 100 parts by mass of a main agent, 40-50 parts by mass of a curing agent and 80-100 parts by mass of a diluent.

9. The process for producing a PU clear primer according to any one of claims 1 to 8, wherein: the method comprises the following steps:

mixing the preparation raw materials of the main agent to obtain the main agent;

mixing the preparation raw materials of the curing agent to obtain the curing agent;

mixing the diluent preparation raw materials to obtain the diluent.

10. A wood product characterized by: comprises a wood body and a coating layer arranged on the surface of the wood body, wherein the coating layer is prepared from the PU transparent primer according to any one of claims 1 to 8; preferably, the wood body is a coal body.

Technical Field

The invention belongs to the technical field of coatings, and particularly relates to a PU transparent primer as well as a preparation method and application thereof.

Background

The coating is traditionally named as paint in China. The coating is a continuous film which is coated on the surface of an object to be protected or decorated and can form firm adhesion with the object to be coated, and is a viscous liquid which is prepared by taking resin, oil or emulsion as a main material, adding or not adding pigments and fillers, adding corresponding auxiliaries and using an organic solvent or water.

The wood products are widely used in various places of human life, such as furniture, doors and windows, wall panels, floors, daily necessities, wooden musical instruments, sports goods, stationery, children toys and the like, and can be made of wood. Unlike other materials, wood has a range of variability, including density, durability, dimensional stability and absorbency, which makes direct application of the wood difficult, and must be surface treated to make the properties stable for long term use as an industrial material. The coating is a common technique for wood surface treatment, and the coating applied on the wood products is called wood coating in general. In the related art, common wood coatings include polyester paint and polyurethane Paint (PU), wherein the polyurethane paint is widely applied to wood furniture and wood floors due to its tough paint film, full gloss, strong adhesion, water resistance, wear resistance and corrosion resistance.

Blackwood (african zebra wood), also known as ebony, has an extremely beautiful texture, a better texture, is resistant to decay, is not easily damaged by worms, and is a valuable timber. However, it is also prone to deformation and cracking due to changes in water content, and is difficult to adapt to use environments such as supercooling, overheating, overdrying, or overwetting. The method for coating the PU transparent primer on the surface of the ebony is a common processing method, and the PU transparent primer can better improve the problems. However, the PU transparent primer on the market at present has the problems of peculiar smell, poor gloss and the like, so that the using effect is still not ideal.

Therefore, the PU transparent primer which is well filled and is prevented from color change and sinking has important significance.

Statements in this background are not admitted to be prior art to the present disclosure.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art described above. Therefore, the invention provides the PU transparent primer which can be odorless and has good glossiness.

The invention also provides a preparation method of the PU transparent primer.

The invention also provides an application of the PU transparent primer.

According to one aspect of the invention, the PU transparent primer comprises a main agent, a curing agent and a diluent, wherein the main agent is prepared from raw materials including odor-purifying alkyd resin, butyl acetate, fatty acid zinc powder, particle powder, a semi-finished product for preventing slurry sedimentation and a semi-finished product for vinyl chloride-Vinyl Acetate (VAGH) liquid.

According to a preferred embodiment of the present invention, at least the following advantages are provided: the primer of the scheme of the invention contains the main agent, the curing agent and the diluent, and can be used for primer coating after the main agent, the curing agent and the diluent are directly and fully stirred uniformly, so that the primer is simple and convenient to use and has strong applicability; wherein, in the main agent, the odor-removing alkyd resin is used as the main component, so that the primer has the advantages of excellent odor removal and cracking resistance, and effectively solves the problems of odor removal and cracking resistance of the existing primer; the zinc powder can effectively improve the polishing performance of the primer; the particle powder can effectively fill pores of wood, prevent the primer from sinking, and simultaneously improve the transparency of the primer; butyl acetate is used as a solvent, so that the environment is protected; after the main agent, the curing agent and the diluent are mixed, the pure-flavor PU ultra-clear particle transparent primer which has the advantages of pure flavor, cracking resistance, good filling property, high transparency, color change prevention, sinking prevention and rib swelling prevention can be prepared, the problems of color change, film sinking and the like caused by easy deformation and cracking, poor filling and inconsistent visible light oxidation of the existing wood paint can be effectively solved, the primer coating method can be suitable for primer coating of solid wood furniture such as various black gold wood and the like or other products, the coating problems of furniture factories and the like are effectively solved, the coating quality is improved, and the added value of products is increased.

In some embodiments of the invention, the ratio of the mass parts of the main agent, the odor-purifying alkyd resin, the butyl acetate, the fatty acid zinc powder, the particle powder, the anti-settling semi-finished product and the vinyl chloride-Vinyl Acetate (VAGH) liquid semi-finished product is 62-84: 5-10: 1-5: 3-8: 2-6.

In some embodiments of the invention, the neat alkyd resin is a modified neat alkyd resin; preferably, the modified neat acid resin consists of a monobasic acid; more preferably, the modified neat alkyd resin is selected from modified neat alkyd resin a1428-68, from badji corporation.

In some embodiments of the invention, the fatty acid zinc powder is zinc stearate powder.

In some embodiments of the invention, the granular powder is a sand flour. The transparency of the primer can be better improved.

In some embodiments of the invention, the anti-settling semi-finished product comprises a neat alkyd resin, butyl acetate, bentonite, and polyamide wax; preferably, the polyamide wax slurry is modified polyethylene micropowder wax slurry; more preferably, in the anti-settling semi-finished product, the ratio of the odor-removing alkyd resin, the butyl acetate, the bentonite and the polyamide wax pulp in parts by weight is 40-60: 20-30: 5-10: 10-20. The anti-settling semi-finished product containing bentonite and polyamide wax slurry is adopted, so that the thixotropy and viscosity of the primer can be effectively improved, and the filler can be effectively prevented from settling in the construction process to cause uneven gloss of a paint film after the paint film is dried; the polyamide wax slurry can effectively prevent the precipitation problem of the particle powder and the zinc powder in the use process of paint mixing, and avoids the influence on the construction operability.

In some preferred embodiments of the invention, the bentonite is an organobentonite.

In some embodiments of the invention, the VAGH liquid intermediate comprises VAGH, methyl isobutyl ketone, propylene glycol methyl ether acetate, and butyl acetate; preferably, in the VAGH liquid semi-finished product, the ratio of the parts by weight of VAGH, methyl isobutyl ketone, propylene glycol methyl ether acetate and butyl acetate is 20-40: 10-20: 20-30: 20-40. The VAGH has strong adhesive force, so that the paint is not easy to drop after the primer is formed into a film.

In some preferred embodiments of the present invention, the preparation raw material of the main agent further comprises a dispersant; preferably a polymeric dispersant. The addition of the dispersing agent is favorable for shortening the dispersing time of the primer, preventing flocculation and sedimentation and being favorable for long-term stable storage.

In some preferred embodiments of the present invention, the preparation raw material of the main agent further comprises an antifoaming agent; preferably, the defoaming agent is a defoaming polymer and/or a polysiloxane solution. The addition of the defoaming agent can effectively remove bubbles generated in the production process of the primer and can inhibit the bubbles generated in the construction process of the primer.

In some preferred embodiments of the present invention, the preparation raw material of the main agent further comprises a leveling agent; preferably, the leveling agent is polyether modified polydimethylsiloxane. The addition of the leveling agent can reduce the surface tension of the primer, can quickly promote self-leveling in the construction process, and cannot generate the morbid phenomena of orange peel, shrinkage cavity and the like.

In some embodiments of the present invention, the raw materials for preparing the curing agent include butyl acetate, aliphatic polyisocyanate, and isocyanate prepolymer; preferably, the aliphatic polyisocyanate is Hexamethylene Diisocyanate (HDI) trimer; preferably, the isocyanate prepolymer is hexamethylene diisocyanate based polyisocyanate; more preferably, in the curing agent, the ratio of the butyl acetate to the HDI trimer to the isocyanate prepolymer in parts by mass is 40-60: 15-25: 20-40. The HDI tripolymer and the isocyanic acid prepolymer which are taken as the curing agent are normal-temperature curing agents, namely the curing can be realized at normal temperature, and the curing agent is energy-saving, environment-friendly and convenient to use.

In some embodiments of the invention, the diluent is a non-reactive diluent; preferably, the diluent is prepared from butyl acetate, propylene glycol methyl ether acetate, cyclohexanone and dimethyl carbonate; more preferably, in the diluent, the mass part ratio of butyl acetate, propylene glycol methyl ether acetate, cyclohexanone and dimethyl carbonate is 35-55: 35-45: 2-5: 13-20. The diluent is prepared by adopting solvents such as butyl acetate, propylene glycol methyl ether acetate and the like, the butyl acetate, the propylene glycol methyl ether acetate, cyclohexanone, dimethyl carbonate and the like can be used as a main agent and a curing agent in the clear PU ultra-clear particle transparent primer of the Uygur honeysuckle for dilution and blending, and further promote the dissolution of other components in the diluent and the formulation of an environment-friendly benzene-free solvent, and the parameters such as VOC and the like are far lower than the new national standard.

In some embodiments of the invention, the PU transparent primer comprises 100 parts by mass of a main agent, 40-50 parts by mass of a curing agent and 60-100 parts by mass of a diluent; preferably, the PU transparent primer comprises 100 parts by mass of a main agent, 40-50 parts by mass of a curing agent and 80-100 parts by mass of a diluent. The coating is better in coating effect by mixing the components in parts by mass.

According to another aspect of the present invention, a method for preparing the primer is provided, which comprises the following steps:

mixing the preparation raw materials of the main agent to obtain the main agent;

mixing the preparation raw materials of the curing agent to obtain the curing agent;

mixing the diluent preparation raw materials to obtain the diluent.

The preparation method according to a preferred embodiment of the present invention has at least the following advantageous effects: the primer of the scheme of the invention has simple and convenient preparation operation and good industrial application prospect; the three are stored separately, and when in use, the product can be prepared, and has stable performance and convenient use.

In some embodiments of the invention, the preparation raw materials of the main agent comprise butyl acetate odor-free alkyd resin, a dispersing agent, a defoaming agent, fatty acid zinc powder, granular powder, butyl acetate, a leveling agent, an anti-settling semi-finished product, a VAGH liquid semi-finished product and butyl acetate, wherein the butyl acetate is added in three times, the odor-free alkyd resin is firstly mixed with the dispersing agent and the defoaming agent, and the butyl acetate I is added; adding fatty acid zinc powder, particle powder and butyl acetate II, and finally adding a leveling agent, an anti-settling slurry semi-finished product, a VAGH liquid semi-finished product and butyl acetate III; wherein the weight ratio of butyl acetate I is 50-70%, the weight ratio of butyl acetate II is about 5-15%, and the balance is butyl acetate III. The effect of dissolving is better when the solution is added for three times.

In some embodiments of the invention, the weight ratio of butyl acetate I is 50% to 60%, the weight ratio of butyl acetate II is about 10%, and the balance butyl acetate III.

According to a further aspect of the invention, the use of the above primer in the production of wood products is proposed.

A wood product comprises a wood body and a coating arranged on the surface of the wood body, wherein the coating is prepared from the primer.

In some preferred embodiments of the invention, the wood body is a blackwood body. The primer disclosed by the scheme of the invention is particularly suitable for preparing a hard gold wood product.

The application according to a preferred embodiment of the invention has at least the following advantageous effects: various performance indexes of the primer basically meet the technical requirements of new national standards GB18581-2020 and GB/T23997-2009; the coating agent can be suitable for primer coating of various solid wood furniture such as black gold and the like, has the advantages of being odorless, high in flexibility, crack resistant, high in transparency, good in polishing performance and filling performance, enabling the wood veneer decorative surface not to be prone to color change, fading, sinking resistance and the like, can practically solve the coating problem in the preparation process of wooden products such as furniture factories and the like, and improves the coating quality and the added value of products.

Detailed Description

The concept and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments to fully understand the objects, features and effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention. The test methods used in the examples are all conventional methods unless otherwise specified; the materials, reagents and the like used are commercially available reagents and materials unless otherwise specified. The sources of reagents used in the following examples and comparative examples are as follows: the odor-removing alkyd resin is purchased from Shandong Bad and has the model number of A1428-68; the dispersant is purchased from Effkona and has the model number of AFCONA 4010; defoamer available from digao corporation, model TEGO Airex 931; zinc fatty acid powder was purchased from huamingtai technologies, zinc stearate BT 1839; the granular powder is purchased from longhai chemical company, model number sand flour 380; the leveling agent is purchased from Digao corporation, model TEGO 300; bentonite for the anti-settling slurry semi-finished product was purchased from Fenghong corporation BS-1B, and polyamide wax slurry was purchased from Disbaron corporation, model number wax slurry 6900-20X; VAGH for the VAGH liquid semi-finished product is purchased from Jiangmen Riyeye, model number of vinyl chloride-vinyl acetate resin; HDI trimer was purchased from Pasteur corporation, model HI 100; isocyanate prepolymer was purchased from kossi corporation, model IL 1351; butyl acetate, propylene glycol methyl ether acetate, cyclohexanone, dimethyl carbonate were purchased from jiang courtship.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

In the description of the present invention, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Example 1

This example prepares a PU clear primer, which is composed of 100 parts by weight of a main agent, 40 parts by weight of a curing agent and 80 parts by weight of a diluent.

The main agent is prepared from the following components in percentage by weight: 77.8 percent of odor-free alkyd resin, 0.3 percent of dispersant, 0.3 percent of defoamer, 3 percent of fatty acid zinc powder, 5 percent of particle powder, 0.1 percent of flatting agent, 3 percent of anti-settling slurry semi-finished product, 3 percent of VAGH liquid semi-finished product and butyl acetate (the rest).

The anti-settling slurry semi-finished product is prepared from the following components in percentage by weight: 50% of odor-removing alkyd resin, 30% of butyl acetate, 5% of bentonite and 15% of polyamide wax slurry.

The VAGH liquid semi-finished product is prepared from the following components in percentage by weight: 40% of VAGH, 20% of methyl isobutyl ketone, 20% of propylene glycol methyl ether acetate and 20% of butyl acetate.

The curing agent is prepared from the following components in percentage by weight: 50% of butyl acetate, 25% of HDI trimer and 25% of isocyanate prepolymer.

The diluent is prepared from the following components in percentage by weight: 37% of butyl acetate, 43% of propylene glycol methyl ether acetate, 3% of cyclohexanone and 17% of dimethyl carbonate.

The preparation process comprises the following steps: the raw materials are weighed according to the proportion and are uniformly mixed (the speed of 800rpm is uniform for stirring) to prepare the main agent, the curing agent and the diluent for standby. The butyl acetate in the main agent is divided into butyl acetate I, II and III which are added for three times, the odor-removing alkyd resin is mixed with the dispersant and the defoamer, and the butyl acetate I is added; adding fatty acid zinc powder, particle powder and butyl acetate II, and finally adding a leveling agent, an anti-settling slurry semi-finished product, a VAGH liquid semi-finished product and butyl acetate III; wherein the weight ratio of butyl acetate I (the weight ratio of the total butyl acetate in the main agent) is 53.3%, the weight ratio of butyl acetate II is about 13.3%, and the balance is butyl acetate III. And then uniformly mixing the main agent, the curing agent and the diluent to prepare the PU transparent primer.

Example 2

This example prepares a PU clear primer, which is composed of 100 parts by weight of a main agent, 50 parts by weight of a curing agent and 80 parts by weight of a diluent.

The main agent is prepared from the following components in percentage by weight: 68 percent of odor-free alkyd resin, 1 percent of dispersing agent, 1 percent of defoaming agent, 5 percent of fatty acid zinc powder, 7 percent of particle powder, 0.5 percent of flatting agent, 5 percent of anti-settling slurry semi-finished product, 5 percent of VAGH liquid semi-finished product and butyl acetate (the rest).

The anti-settling slurry semi-finished product is prepared from the following components in percentage by weight: 45% of odor-free alkyd resin, 25% of butyl acetate, 8% of bentonite and 22% of polyamide wax slurry.

The VAGH liquid semi-finished product is prepared from the following components in percentage by weight: 40% of VAGH, 20% of methyl isobutyl ketone, 20% of propylene glycol methyl ether acetate and 20% of butyl acetate.

The curing agent is prepared from the following components in percentage by weight: 42% butyl acetate, 18% HDI trimer and 40% isocyanate prepolymer.

The diluent is prepared from the following components in percentage by weight: 50% of butyl acetate, 35% of propylene glycol methyl ether acetate, 5% of cyclohexanone and 10% of dimethyl carbonate.

The preparation process comprises the following steps: the raw materials are weighed according to the proportion and are uniformly mixed (the speed of 800rpm is uniform for stirring) to prepare the main agent, the curing agent and the diluent for standby. The butyl acetate in the main agent is divided into butyl acetate I, II and III which are added for three times, the odor-removing alkyd resin is mixed with the dispersant and the defoamer, and the butyl acetate I is added; adding fatty acid zinc powder, particle powder and butyl acetate II, and finally adding a leveling agent, an anti-settling slurry semi-finished product, a VAGH liquid semi-finished product and butyl acetate III; wherein the weight ratio of the butyl acetate I (the weight ratio of the butyl acetate in the main agent) is 66.7%, the weight ratio of the butyl acetate II is about 6.7%, and the balance is butyl acetate III. And then uniformly mixing the main agent, the curing agent and the diluent to prepare the PU transparent primer.

Example 3

This example prepares a PU clear primer, which is composed of 100 parts by weight of a main agent, 30 parts by weight of a curing agent and 100 parts by weight of a diluent.

The main agent is prepared from the following components in percentage by weight: 68 percent of odor-free alkyd resin, 1 percent of dispersing agent, 1 percent of defoaming agent, 5 percent of fatty acid zinc powder, 7 percent of particle powder, 0.5 percent of flatting agent, 5 percent of anti-settling slurry semi-finished product, 5 percent of VAGH liquid semi-finished product and butyl acetate (the rest).

The anti-settling slurry semi-finished product is prepared from the following components in percentage by weight: 45% of odor-free alkyd resin, 25% of butyl acetate, 8% of bentonite and 22% of polyamide wax slurry.

The VAGH liquid semi-finished product is prepared from the following components in percentage by weight: 40% of VAGH, 20% of methyl isobutyl ketone, 20% of propylene glycol methyl ether acetate and 20% of butyl acetate.

The curing agent is prepared from the following components in percentage by weight: 42% butyl acetate, 18% HDI trimer and 40% isocyanate prepolymer.

The diluent is prepared from the following components in percentage by weight: 50% of butyl acetate, 35% of propylene glycol methyl ether acetate, 5% of cyclohexanone and 10% of dimethyl carbonate.

The preparation process comprises the following steps: the raw materials are weighed according to the proportion and are uniformly mixed (the speed of 800rpm is uniform for stirring) to prepare the main agent, the curing agent and the diluent for standby. The butyl acetate in the main agent is divided into butyl acetate I, II and III which are added for three times, the odor-removing alkyd resin is mixed with the dispersant and the defoamer, and the butyl acetate I is added; adding fatty acid zinc powder, particle powder and butyl acetate II, and finally adding a leveling agent, an anti-settling slurry semi-finished product, a VAGH liquid semi-finished product and butyl acetate III; wherein the weight ratio of butyl acetate I (the weight ratio of the total butyl acetate in the main agent) is 53.3%, the weight ratio of butyl acetate II is about 13.3%, and the balance is butyl acetate III. And then uniformly mixing the main agent, the curing agent and the diluent to prepare the PU transparent primer.

Example 4

This example prepares a PU clear primer, which is composed of 100 parts by weight of a main agent, 50 parts by weight of a curing agent and 80 parts by weight of a diluent.

The main agent is prepared from the following components in percentage by weight: 68 percent of odor-free alkyd resin, 1 percent of dispersing agent, 1 percent of defoaming agent, 5 percent of fatty acid zinc powder, 7 percent of particle powder, 0.5 percent of flatting agent, 5 percent of anti-settling slurry semi-finished product, 5 percent of VAGH liquid semi-finished product and butyl acetate (the rest).

The anti-settling slurry semi-finished product is prepared from the following components in percentage by weight: 68.5% xylene, 20% high molecular weight short oil alkyd resin, 1.5% EFCONA 5054 dispersant, and 10% BENTONE 34 bentonite.

The VAGH liquid semi-finished product is prepared from the following components in percentage by weight: 40% of VAGH, 20% of methyl isobutyl ketone, 20% of propylene glycol methyl ether acetate and 20% of butyl acetate.

The curing agent is prepared from the following components in percentage by weight: 42% butyl acetate, 18% HDI trimer and 40% isocyanate prepolymer.

The diluent is prepared from the following components in percentage by weight: 50% of butyl acetate, 35% of propylene glycol methyl ether acetate, 5% of cyclohexanone and 10% of dimethyl carbonate.

The preparation process comprises the following steps: the raw materials are weighed according to the proportion and are uniformly mixed (the speed of 800rpm is uniform for stirring) to prepare the main agent, the curing agent and the diluent for standby. The butyl acetate in the main agent is divided into butyl acetate I, II and III which are added for three times, the odor-removing alkyd resin is mixed with the dispersant and the defoamer, and the butyl acetate I is added; adding fatty acid zinc powder, particle powder and butyl acetate II, and finally adding a leveling agent, an anti-settling slurry semi-finished product, a VAGH liquid semi-finished product and butyl acetate III; wherein the weight ratio of butyl acetate I (the weight ratio of the total butyl acetate in the main agent) is 53.3%, the weight ratio of butyl acetate II is about 13.3%, and the balance is butyl acetate III. And then uniformly mixing the main agent, the curing agent and the diluent to prepare the PU transparent primer.

Comparative example 1

This comparative example prepared a PU clear primer, which differs from example one in that the absence of fatty acid zinc powder was replaced with an equal amount of silica powder.

Comparative example 2

This example prepared a PU clear primer, which differs from example one in that no particulate powder was used, and an equal amount of talc was used instead.

The PU transparent primers prepared in the above examples and comparative examples were sprayed on the surface of ebony gold by a manipulator according to the conventional setting, and the corresponding paint film properties were tested. The detection is carried out according to the standard of GB18581-2020 Limited amount of harmful substances in solvent type wood coatings of interior decoration and finishing materials, and the results are shown in the following table 1.

TABLE 1

As can be seen from the above table, when the content of the curing agent is lower, the drying time is obviously prolonged, and when the components of the anti-settling semi-finished product are changed, the effect is reduced, but the requirements of GB18581-2020 are basically met; the primer does not contain fatty acid zinc powder, even if other fillers are used for replacing the primer, the sanding property is poor, the drying time of the primer does not contain the particle powder, and therefore the particle powder and other components have a certain synergistic effect in the drying time; the primer added with the particle powder has better anti-sinking performance, if not added, the performance is poorer, and meanwhile, the zinc powder also has a certain synergistic effect on the anti-sinking performance.

While the embodiments of the present invention have been described in detail with reference to the specific embodiments, the present invention is not limited to the embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.