阅读说明：本技术 一种利于上粉且抗固化滑落的粉末涂料及其应用 (Powder coating facilitating powdering and resisting solidification and sliding and application thereof ) 是由 汪志成 糜震宇 于 2019-11-29 设计创作，主要内容包括：本发明公开了一种利于上粉且抗固化滑落的粉末涂料,其原料包括增电剂和耐析出助剂,增电剂用于粉末涂料在静电喷涂时的增电上粉,消除或减少粉末涂料在静电喷涂时的法拉第笼效应；同时耐析出助剂用于避免粉末涂料在进行熔融固化过程中迁移析出,增电剂与耐析出助剂相同或不相同；本发明还提出将粉末涂料应用于具有凹凸结构和/或安装孔和/或不规则边角结构的工件或汽车轮毂螺栓安装孔的涂装；本发明可以实现在静电喷涂时的良好增电上粉,以及在后续进行熔融固化时,避免粉末涂料发生迁移析出,同时实现良好的抗固化滑落效果。(The invention discloses a powder coating which is beneficial to powdering and resistant to solidification and sliding, which comprises raw materials of an electrizer and a precipitation-resistant auxiliary agent, wherein the electrizer is used for electrifying and powdering the powder coating during electrostatic spraying, so that the Faraday cage effect of the powder coating during electrostatic spraying is eliminated or reduced; meanwhile, the precipitation-resistant auxiliary is used for preventing the powder coating from migrating and precipitating in the process of melting and curing, and the electrization accelerator and the precipitation-resistant auxiliary are the same or different; the invention also provides a method for coating the bolt mounting hole of the automobile hub or the workpiece with the concave-convex structure and/or the mounting hole and/or the irregular corner structure by using the powder coating; the invention can realize good electrification and powdering in electrostatic spraying, prevent the powder coating from migrating and separating out in the subsequent melting and solidification, and simultaneously realize good anti-curing and anti-sliding effects.)

1. The powder coating which is beneficial to powdering and resists solidification and sliding is characterized in that raw materials of the powder coating comprise an energizer and a precipitation-resistant auxiliary agent, wherein the energizer is used for electrifying and powdering the powder coating during electrostatic spraying to eliminate or reduce the Faraday cage effect of the powder coating during electrostatic spraying; and meanwhile, the precipitation-resistant auxiliary is used for preventing the powder coating from migrating and precipitating in the process of melting and curing, and the electrization accelerator is the same as or different from the precipitation-resistant auxiliary.

2. Powder coating facilitating powdering and being resistant to curing and sliding according to claim 1, characterised in that the electrization accelerator comprises monoglycerides, and/or that the monoglycerides act as the precipitation-resistant aid at the same time.

3. The powderous, powderous coating facilitating powdering and resistant to curing and sliding according to claim 1, wherein said precipitation-resistant aid comprises a polyacrylic or polyethylene wax powder, which simultaneously acts as a degassing agent.

4. Advantageous powdering and cure slip resistant powder coating according to claim 1 or 2 or 3, wherein the molecular weight of the bleed assistant is not higher than 20000.

5. The powdering-facilitated and solidification slip-resistant powder coating according to claim 1, 2 or 3, wherein the electrization agent is not less than 0.02% by weight of said powder coating, and the precipitation-resistant aid is not less than 0.02% by weight of said powder coating.

6. The powdering-facilitated and solidification slip-resistant powder coating according to claim 1, 2 or 3, wherein the electrization accelerator is present in an amount ranging from 0.05 to 0.5% by weight of said powder coating, and wherein the precipitation-resistant aid is present in an amount ranging from 0.05 to 1.5% by weight of said powder coating.

7. A powderous, curable slip-resistant powder coating according to claim 1, 2 or 3, wherein said powder coating raw materials comprise epoxy resins and polyester resins, said epoxy resins and said polyester resins being capable of undergoing a cross-linking curing reaction.

8. The powdering paint of claim 7, wherein the epoxy resin is present in an amount ranging from 10 to 50% by weight of the powder coating, and the polyester resin is present in an amount ranging from 25 to 80% by weight of the powder coating.

9. Use of a powder coating according to any one of claims 1 to 8, characterized in that the powder coating is applied to the coating of workpieces having a relief structure and/or mounting holes and/or irregular corner structures.

10. The application of the powder coating as claimed in any one of claims 1 to 8, wherein the powder coating is applied to coating of an automobile hub, the automobile hub comprises mounting holes, the bolt mounting holes comprise bolt mounting holes located on the outer side and bolt mounting holes located on the inner side, the powder coating is sprayed and cured on the automobile hub, a base coating is formed on a base material of the automobile hub, and a mounting hole protective coating is formed on the inner periphery of the bolt mounting holes.

11. The use of a powder coating according to claim 10, wherein the primer coating has a thickness in the range of 100-150 microns and the mounting hole protective coating has a thickness in the range of 20-80 microns.

Technical Field

The invention belongs to the field of thermosetting powder coatings, and particularly relates to a powder coating which is beneficial to powdering and resistant to solidification and sliding.

Background

With the enhancement of domestic environmental protection consciousness, people increasingly hope to replace liquid paint with environment-friendly thermosetting powder coating to realize environment-friendly coating protection. Particularly, automobile wheel hub also is thermosetting powder coating's main application field, and along with powder coating in automobile wheel hub's continuous deep application, automobile coating producer has fed back some application technical problem, mainly embodies: because automobile wheel hub bolt hole department is darker, is unfavorable for the powdering, and in powder coating carries out the melt solidification process in bolt hole department simultaneously, the powder coating that is in the molten state is easy to be followed bolt hole (its maximum hole depth usually reaches 4-6cm) and is located the landing, leads to being located the relative weakness of coating protection department of bolt hole department, and this obviously can cause negative effects to automobile wheel hub's life.

As the applicant knows the conventional technology of the technical personnel in the field, β -hydroxyalkyl amide is usually adopted as a charging agent to improve the charging and powdering capability of the powder coating in order to improve the charging and powdering problem in the bolt hole of the automobile hub in the prior art, but the technical scheme has obvious slipping problem when the subsequent melt crosslinking and curing are carried out.

The applicant consults a large amount of prior art documents and finds that research on the technical problem is carried out in the field of powder coating, so the applicant particularly sets up research and development subjects to research and develop the technical problem.

Disclosure of Invention

In view of the above, the present invention provides a powder coating with good powder-adding and anti-sliding properties and an application thereof, which can achieve good powder-adding during electrostatic spraying, prevent migration and precipitation of the powder coating during subsequent melt-curing, and achieve good anti-sliding properties.

The technical scheme adopted by the invention is as follows:

the powder coating which is beneficial to powdering and resists solidification and slipping comprises raw materials of an energizer and a precipitation-resistant auxiliary agent, wherein the energizer is used for electrifying and powdering the powder coating during electrostatic spraying, so that the Faraday cage effect of the powder coating during electrostatic spraying is eliminated or reduced; and meanwhile, the precipitation-resistant auxiliary is used for preventing the powder coating from migrating and precipitating in the process of melting and curing, and the electrization accelerator is the same as or different from the precipitation-resistant auxiliary.

Preferably, the current enhancer comprises monoglyceride,/and the monoglyceride simultaneously serves as the precipitation-resistant aid.

Preferably, the precipitation-resistant auxiliary agent comprises polyacrylic acid wax powder or polyethylene wax powder, and the polyacrylic acid wax powder or the polyethylene wax powder simultaneously serves as a degassing agent.

Preferably, the powder coating material does not comprise EBS amide wax or polytetrafluoroethylene wax.

Preferably, the molecular weight of the bleed-out resistance aid is not higher than 20000.

Preferably, the weight portion of the electrization accelerator in the powder coating is not less than 0.02%, and the weight portion of the precipitation-resistant auxiliary in the powder coating is not less than 0.02%.

Preferably, the weight portion range of the energizer in the powder coating is 0.05-0.5%, and the weight portion range of the precipitation-resistant auxiliary in the powder coating is 0.05-1.5%.

Preferably, the powder coating material comprises an epoxy resin and a polyester resin, and the epoxy resin and the polyester resin can perform a crosslinking curing reaction.

Preferably, the epoxy resin accounts for 10-50% of the weight of the powder coating, and the polyester resin accounts for 25-80% of the weight of the powder coating; more preferably, the epoxy resin accounts for 30-35% of the powder coating, and the polyester resin accounts for 45-52% of the powder coating.

Preferably, the powder coating is applied to the coating of the workpiece with the concave-convex structure and/or the mounting hole and/or the irregular corner structure.

Preferably, the application of the powder coating is to apply the powder coating to the coating of an automobile hub, the automobile hub comprises a mounting hole, the bolt mounting hole comprises a bolt mounting hole located on the outer side and a screw mounting hole located on the inner side, the powder coating is sprayed and cured on the automobile hub, a base coating is formed on the automobile hub substrate, and a mounting hole protective coating is formed on the inner periphery of the bolt mounting hole.

Preferably, the thickness of the primary coating is in the range of 100-150 microns, and the mounting hole protective coating is in the range of 20-80 microns.

In the process of research and development of a subject of special research and development, the applicant also discovers a new functional application of monoglyceride, and quite surprisingly discovers that the monoglyceride has a very excellent power increasing function and simultaneously has an excellent precipitation resistance function.

Preferably, the monoglyceride comprises the following molecular structural formula:

preferably, the weight portion of the electrization agent in the powder coating ranges from 0.02% to 0.5%.

Preferably, the weight portion of the electrization agent in the powder coating ranges from 0.05% to 0.2%.

Preferably, the powder coating is applied to the coating of the workpiece with the concave-convex structure and/or the mounting hole and/or the irregular corner structure.

Preferably, the powder coating is applied to coating of an automobile hub, the automobile hub comprises a mounting hole, the bolt mounting hole comprises a bolt mounting hole located on the outer side and a bolt mounting hole located on the inner side, the powder coating is sprayed and cured on the automobile hub, a base coating is obtained by molding on an automobile hub substrate, and a mounting hole protective coating is obtained by molding on the inner periphery of the bolt mounting hole.

Preferably, the powder coating comprises raw materials of thermosetting resin and a curing agent for curing the thermosetting resin, and the raw materials also comprise the charging agent.

Preferably, the raw materials comprise thermosetting resin and a curing agent, and the thermosetting resin is selected from one or a mixture of more of pure epoxy resin, polyester resin, polyurethane resin, acrylic resin and fluorocarbon resin.

Preferably, the automobile hub comprises a mounting hole, the bolt mounting hole comprises a bolt mounting hole located on the outer side and a bolt mounting hole located on the inner side, the automobile hub is coated and protected by the powder coating, a base coating is obtained by molding on an automobile hub substrate, and a mounting hole protective coating is obtained by molding in the bolt mounting hole.

In the process of carrying out special research and development, the applicant finds that two technical schemes need to be adopted simultaneously to solve the technical problem of coating deep holes or anisotropic corner workpieces: adding an electrifier into the powder coating for electrifying and powdering during electrostatic spraying, and simultaneously eliminating or reducing the Faraday cage effect of the powder coating during electrostatic spraying; in a second aspect: meanwhile, a precipitation-resistant auxiliary agent is required in the powder coating for preventing the powder coating from migrating and precipitating in the melting and curing process, and by the design and combination of the technical schemes in the two aspects, good power-increasing and powder-feeding can be finally realized, and when the powder coating is melted and cured after good power-increasing and powder-feeding is realized, the powder coating is prevented from migrating and precipitating, and finally, a good anti-curing and anti-sliding effect is realized; the applicant particularly finds that EBS amide wax or polytetrafluoroethylene wax is often used as a degassing agent in the powder coating formula in the prior art, and the EBS amide wax and the polytetrafluoroethylene wax can cause obvious migration and precipitation problems of the powder coating during melting and solidification, and further cause the problem of slipping, so that the EBS amide wax and the polytetrafluoroethylene wax are not suitable for being used as raw materials of the powder coating which is beneficial to powdering and resists solidification and slipping;

the invention also creatively provides a monoglyceride as an electrizer of the powder coating, and the applicant surprisingly finds that the monoglyceride which is conventionally used as a surfactant or a dispersant is used as the electrizer of the powder coating, so that not only can more excellent electrizationpowdering effect be realized, but also the monoglyceride has excellent migration-precipitation resistance function due to good compatibility with a thermosetting resin curing system in the melting and curing process, and therefore, the monoglyceride can also be directly used as a precipitation-resistance auxiliary agent as a preferred scheme; the applicant has also found that polyacrylic acid wax powder or polyethylene wax powder can be used as the precipitation-resistant aid of the present invention, and the same technical effects can be achieved by using polyacrylic acid wax powder or polyethylene wax powder as the degassing agent of the present invention.

Drawings

FIG. 1 is a photograph showing the powdering effect of the powder coating of this embodiment 1 after electrostatic spraying in the mounting hole of the bolt of the automobile hub;

FIG. 2 is a schematic view of a coating forming structure of the powder coating in the mounting hole of the automobile hub bolt in this embodiment 1;

FIG. 3 is a photograph showing the powdering effect of the powder coating of this embodiment 3 after electrostatic spraying in the mounting hole of the automobile hub bolt;

FIG. 4 is a photograph showing the powdering effect of the powder coating of comparative example 3 after electrostatic spraying in the mounting hole of the automobile hub bolt.

Detailed Description

The embodiment of the invention discloses a powder coating which is beneficial to powdering and resistant to solidification and sliding, and the raw materials of the powder coating comprise an electrizer and a precipitation-resistant auxiliary agent, wherein the electrizer is used for electrifying and powdering the powder coating during electrostatic spraying, so that the Faraday cage effect of the powder coating during electrostatic spraying is eliminated or reduced; and meanwhile, the precipitation-resistant auxiliary is used for preventing the powder coating from migrating and precipitating in the process of melting and curing, and the electrization accelerator is the same as or different from the precipitation-resistant auxiliary.

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment firstly provides an electrizer for powder coating, wherein the electrizer for powder coating adopts monoglyceride for electrifying and powdering the powder coating during electrostatic spraying, so as to eliminate or reduce the Faraday cage effect of the powder coating during electrostatic spraying; the monoglyceride comprises the following molecular structural formula:

preferably, the monoglyceride accounts for 0.02-0.5% of the weight of the powder coating; more preferably, the monoglyceride is present in the powder coating in an amount in the range of 0.05 to 0.2% by weight.

The embodiment proposes that the powder coating taking the monoglyceride as the charging agent is particularly suitable for being applied to coating of workpieces with concave-convex structures and/or mounting holes and/or irregular corner structures, has very good charging and powdering effects, and can avoid the problem of migration and precipitation during the melting and curing process of the powder coating, so that the problem of slipping does not occur even if the powder coating is applied to coating of workpieces with concave-convex structures and/or mounting holes and/or irregular corner structures.

In the practical application of monoglyceride as an electric conduction enhancer to powder coating, a curing combination system of thermosetting resin and a curing agent adopted by the powder coating is not particularly limited, and the curing combination system can be selected according to the coating protection requirement of a workpiece substrate to be applied in practice, specifically, the raw materials comprise thermosetting resin and the curing agent, and the thermosetting resin is selected from one or a mixture of more of pure epoxy resin, polyester resin, polyurethane resin, acrylic resin and fluorocarbon resin; when the epoxy resin and the polyester resin are applied to the automobile hub substrate, the applicant suggests that the preferred raw material system adopts the epoxy resin and the polyester resin, and the epoxy resin and the polyester resin can generate a crosslinking curing reaction to ensure the anti-corrosion effect on the hub substrate; further preferably, the epoxy resin accounts for 10-50% of the powder coating, and the polyester resin accounts for 25-80% of the powder coating.

The embodiment of the application also specifically provides a powder coating which is beneficial to powdering and resistant to solidification and slipping, the raw materials of the powder coating comprise monoglyceride as described above in the embodiment, the monoglyceride is used as an electric-increasing agent and a precipitation-resistant auxiliary agent at the same time, the electric-increasing agent is used for electrically increasing and powdering the powder coating during electrostatic spraying, and the Faraday cage effect of the powder coating during electrostatic spraying is eliminated or reduced; meanwhile, the precipitation-resistant auxiliary is used for preventing the powder coating from migrating and precipitating in the process of melting and curing, and the electrization accelerator and the precipitation-resistant auxiliary are the same or different; specifically, in order to avoid the serious slip problem caused by migration and precipitation of the powder coating during melt-curing, this example strongly suggests that the powder coating raw material does not use a raw material such as EBS amide wax or polytetrafluoroethylene wax as a degassing agent for the powder coating;

on the principle of selecting parts by weight, the part by weight of the electrization agent in the powder coating is not less than 0.02%, the part by weight of the precipitation-resistant auxiliary agent in the powder coating is not less than 0.02%, otherwise, the technical effect is not obvious enough, and the basic standard requirements of powdering and anti-curing and anti-sliding after application and coating cannot be met;

in other embodiments, polyacrylic acid wax powder or polyethylene wax powder is adopted as the precipitation-resistant auxiliary agent, and is simultaneously used as a degassing agent, and the molecular weight of the polyacrylic acid wax powder or the polyethylene wax powder is not higher than 20000 in the selection of molecular weight, and the preferable selection of the molecular weight can further contribute to the migration-resistant effect of the powder coating during melting and curing; preferably, the weight part of the electric conduction agent in the powder coating ranges from 0.05 to 0.5%, more preferably, the weight part of the electric conduction agent in the powder coating ranges from 0.05 to 0.25%, when the adding proportion is more than 0.25%, the electric conduction effect is not obvious, and meanwhile, the worse powdering effect is caused along with the increase of the weight part of the electric conduction agent; the precipitation-resistant auxiliary agent accounts for 0.05-1.5% of the weight of the powder coating.

In other embodiments, this example also does not exclude the use of β -hydroxyalkylamides or monoglycerides as an electron enhancer, and the use of these materials in combination with a migration resistant aid may also provide better technical results, but since these materials do not have a migration resistant function and are also significantly inferior to monoglycerides in terms of their electron enhancing effect, the technical effects are significantly inferior, and therefore, this example is not suggested as a preferred embodiment of the present application.

In order to further illustrate the embodiments and technical effects of the present application, the applicant has specifically designed the following examples and comparative examples: