阅读说明：本技术 一种具有光滑龟纹纹理效果的gma体系粉末涂料 (GMA system powder coating with smooth moire texture effect ) 是由 张皓 陶月红 李卓衡 徐斌 童乃斌 于 2021-04-19 设计创作，主要内容包括：本发明公开了一种具有光滑龟纹纹理效果的GMA体系粉末涂料,涉及粉末涂料技术领域,其原料包括：环氧基官能度组合物、羧基官能度组合物、流平剂、除气剂和/或颜填料；其中,环氧基官能度组合物由环氧树脂、异氰尿酸三缩水甘油酯中的至少一种与含缩水甘油基的丙烯酸树脂组成。本发明粉末涂料中不含龟纹剂并且可以通过一步挤出的施工工艺制备,原料中含有环氧基官能度组合物,其作为固化剂与羧基官能度组合物发生交联反应后能够提供一种光滑龟纹纹理,且龟纹纹理清晰均匀、连续性好,龟纹内部平整,装饰效果显著,重现性好。(The invention discloses GMA system powder coating with smooth moire texture effect, relating to the technical field of powder coating, and the raw materials comprise: epoxy-functional compositions, carboxyl-functional compositions, levelling agents, deaerators and/or pigments and fillers; wherein, the epoxy group functional composition consists of at least one of epoxy resin and triglycidyl isocyanurate and acrylic resin containing glycidyl. The powder coating does not contain a moire agent and can be prepared by a one-step extrusion construction process, the raw materials contain the epoxy group functionality composition, the epoxy group functionality composition serving as a curing agent can provide a smooth moire texture after being subjected to a crosslinking reaction with the carboxyl group functionality composition, and the moire texture is clear, uniform, good in continuity, smooth in moire, remarkable in decorative effect and good in reproducibility.)

1. A GMA system powder coating with smooth moire texture effect is characterized by comprising the following raw materials: epoxy-functional compositions, carboxyl-functional compositions, deaerators, levelling agents and/or pigments and fillers; wherein, the epoxy group functional composition consists of at least one of epoxy resin and triglycidyl isocyanurate and acrylic resin containing glycidyl.

2. GMA-system powder coating with smooth moire texture effect according to claim 1, characterised in that said epoxy-based functionality composition consists of the following components in weight percent: 0-60% of epoxy resin, 0-25% of triglycidyl isocyanurate and 40-95% of glycidyl group-containing acrylic resin.

3. The GMA-based powder coating with smooth moire texture effect as claimed in claim 1 or 2, characterized in that said glycidyl group containing acrylic resin has an epoxy equivalent of 300-1000 and a glass transition temperature of 30-110 ℃.

4. The GMA system powder coating with smooth moire texture effect as claimed in claim 1 or 2, characterized in that said epoxy resin is bisphenol A type epoxy resin with weight average molecular weight of 1200-2500, epoxy value range of 0.09-0.18mol/100g and softening point of 70-110 ℃.

5. The GMA system powder coating with smooth moire texture effect of claim 1, characterized in that the carboxyl functional composition comprises at least a carboxyl functional polyester resin; preferably, an aliphatic dibasic acid or an aliphatic polyanhydride is also included.

6. GMA-system powder coating with smooth moire texture effect according to claim 5, characterised in that the carboxyl functionality composition consists of the following components in weight percent: 97-100% of carboxyl functionality polyester resin, 0-3% of aliphatic dibasic acid and 0-2% of aliphatic polyanhydride.

7. The GMA-system powder coating with smooth moire texture effect as claimed in claim 5 or 6, characterized in that said carboxyl-functional polyester resin has a weight average molecular weight of 1000-40000, an acid value in the range of 10-100mg KOH/g and a glass transition temperature Tg of 40-80 ℃.

8. The GMA-based powder coating having a smooth moire texture effect as claimed in claim 5 or 6 wherein said aliphatic dibasic acid has the formula (I):

wherein x is an integer of 4 to 18.

9. The GMA-based powder coating having a smooth moire texture effect as claimed in claim 5 or 6 wherein said aliphatic polyanhydride has the formula (II):

wherein y is an integer of 4 to 8, and z is an integer of 2 to 18;

preferably, the aliphatic polyanhydride has an acid value in the range of 250-400mg KOH/g and a melting range of 50-170 ℃.

10. GMA-system powder coating with smooth moire texture effect, according to any of the claims 1-9, characterized in that its raw materials, in weight percentage, comprise: 15-35% of epoxy group functionality composition, 53-84% of carboxyl functionality composition, 0.5-0.6% of degasifier, 0-1% of flatting agent and 0-26% of pigment and filler.

Technical Field

The invention relates to the technical field of powder coatings, in particular to a GMA system powder coating with a smooth moire texture effect.

Background

The powder coating is a coating with 100 percent of solid components, is different from the traditional solvent-based and water-based coatings, has almost zero VOC (Volatile Organic Compounds), is free from solvent pollution, is more energy-saving and environment-friendly, and is an environment-friendly coating. Also because of this, the market share of powder coatings is growing rapidly today with increasingly stringent VOC emission standards and driven by the trend of "paint to powder".

With the continuous development of powder coatings, people have not satisfied with the common planar powder coatings, and increasingly demand texture powder coatings with beautiful appearance and strong decorative effect. Such as anti-theft doors, safe cases, hardware tools, office supplies, artware and the like. These powder coatings with a textured decorative effect are mainly wrinkled, lined, snakeskin, hammered, cracked, sanded, etc.

It is well known that for special textures, especially for moir powder coatings as defined in the present invention, curing systems using hydroxy polyester + amino resin (Aminoplast) crosslinkers and special catalysts are customary, which is also a preferred option in the art, since most other powder coating systems such as pure epoxy, epoxy/polyester hybrid, polyester/TGIC, polyester/Hydroxyalkylamide (HAA) and polyester/GMA systems are not easily achievable.

For example, patent CN107151475A discloses a powder coating composition with moire effect. Which consists essentially of one or more hydroxy polyester resins, an amino resin cross-linking agent, a sulfonic acid imide type catalyst, a leveling/degassing agent and a pigment filler, and is incorporated herein by reference in its entirety.

For example, US5695852 discloses the preparation of a coating in the form of a powder with moir e, using a hydroxy polyester, an amino resin cross-linking agent, a diethylamine triflate as catalyst, and a small amount of an epoxy compound.

In addition, patent CN110819189A discloses a base powder prepared from fluorine-modified carboxyl acrylic resin, silicon-modified carboxyl acrylic resin, carboxyl acrylic resin and curing agent TGIC and/or HAA, and then a moire powder coating is prepared by dry blending texturing agent, which is incorporated herein by reference.

At present, the preparation process of the texture powder coating mainly comprises two processes, one is a dry mixing process, and the other is a one-step extrusion process.

The preparation steps of the dry mixing process comprise: (a) preparing base powder meeting the performance requirement in advance, wherein the base powder can contain or not contain a leveling agent; (b) dry blended additives are added to the base powder by dry blending. Dry blending processes are the most widely used technology and many dry blending additives have been developed to suit this type of processing. The dry mixing process needs to prepare specific base powder and/or dry mixing additive in advance, and has complex operation process, high processing difficulty and poor reproducibility of texture. The obtained moire pattern is visually rough, the moire pattern is not smooth enough, the continuity of the moire pattern is difficult to control, and the situation of discontinuous texture is easy to occur.

Patent CN107151475A discloses a dry-mixed additive for powder coating and a texture powder coating provided by the dry-mixed additive, wherein the dry-mixed process is adopted, and the moire powder coating can be obtained by mixing the additive and base powder according to a certain proportion, which is incorporated by reference in the entirety.

It would therefore be highly desirable to develop a new class of powder coatings which are stable to shaping, which improve the disadvantages of the prior art and which can be produced by a one-step extrusion process with a smooth surface and a moir e effect.

Disclosure of Invention

Based on the technical problems in the background art, the invention provides the GMA system powder coating with the smooth moire texture effect, and the obtained coating has clear and uniform moire texture, good continuity, smooth moire inside and obvious decorative effect.

The invention provides GMA system powder coating with smooth moire texture effect, which comprises the following raw materials: epoxy-functional compositions, carboxyl-functional compositions, deaerators, levelling agents and/or pigments and fillers; wherein, the epoxy group functional composition consists of at least one of epoxy resin and triglycidyl isocyanurate and acrylic resin containing glycidyl.

Preferably, the epoxy-functional composition consists of the following components in weight percent: 0-60% of epoxy resin, 0-25% of triglycidyl isocyanurate and 40-95% of glycidyl group-containing acrylic resin.

Preferably, the glycidyl group-containing acrylic resin has an epoxy equivalent of 300-1000 and a glass transition temperature of 30-110 ℃.

In the present invention, the glycidyl group-containing acrylic resin may be prepared by adding an epoxy group-containing monomer to an acrylate comonomer for copolymerization;

the structural formula of the epoxy group-containing monomer is as follows:

wherein R is₁、R₂Is selected from any one of H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl, preferably R₁Is H or methyl, more preferably methyl, preferably R₂Is H;

the acrylic comonomer comprises at least one of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, octyl acrylate, octyl methacrylate, dodecyl acrylate, dodecyl methacrylate, benzyl acrylate and benzyl methacrylate; preferably, the acrylate comonomer further comprises a vinyl monomer, and more preferably, the vinyl monomer is one or two of styrene and methyl styrene.

The glycidyl group-containing acrylic resin is prepared from 15-70 wt% of epoxy group-containing monomer and 30-85 wt% of acrylic comonomer, based on the total weight of the epoxy group-containing monomer and the acrylic comonomer; preferably, the weight percentage of the epoxy group-containing monomer is 25 to 50%, and the weight percentage of the acrylic acid comonomer is 50 to 75%.

The glycidyl group-containing acrylic resin has an epoxy equivalent of 300-; the vitrification conversion temperature is 30-110 ℃, preferably 60-90 ℃.

In the present invention, the above glycidyl group-containing acrylic resin may be obtained by commercially available routes, for example: YH-208 of Wuhan Yanhuang chemical industry, AHA7700 and AHA7570 of Huaan import and export Limited, Anhui province, SA550 and SA580 of Liu' an Jietongda new material Limited, G700 of Wuhan silver science and technology Limited, and the like. As to such glycidyl group-containing acrylic resins, those skilled in the art are well known.

Preferably, the epoxy resin is bisphenol A type epoxy resin, the weight average molecular weight of the epoxy resin is 1200-2500, the epoxy value range is 0.09-0.18mol/100g, and the softening point is 70-110 ℃.

In the present invention, the bisphenol a epoxy resin may be prepared by condensation polymerization of epichlorohydrin and bisphenol a (4, 4' -dihydroxydiphenyl propane) under the action of sodium hydroxide. The bisphenol A type epoxy resin has the weight average molecular weight of 1200-2500, preferably 1300-2400, more preferably 1429-2222; an epoxy value in the range of 0.09 to 0.18mol/100g, preferably 0.09 to 0.14mol/100g, more preferably 0.09 to 0.12mol/100 g; the softening point is 70-110 deg.C, preferably 75-105 deg.C, and more preferably 85-95 deg.C.

In the present invention, the above bisphenol a type epoxy resin can be obtained by a commercially available route, for example: e-12 of Anhuifu New Material science and technology, Inc., and the like. Such epoxy resins are well known to those skilled in the art.

In the present invention, the triglycidyl isocyanurate is TGIC.

The triglycidyl isocyanurate mentioned above is commercially available, for example: araldite PT810 by Huntsman, TEPIC G by Nissan, AHA6810 by Anhui Huaan, and the like. Such triglycidyl isocyanurate is well known to those skilled in the art.

Preferably, the carboxyl-functional composition comprises at least a carboxyl-functional polyester resin; preferably, an aliphatic dibasic acid or an aliphatic polyanhydride is also included.

Preferably, the carboxyl functionality composition consists of the following components in weight percent: 97-100% of carboxyl functionality polyester resin, 0-3% of aliphatic dibasic acid and 0-2% of aliphatic polyanhydride.

Preferably, the weight average molecular weight of the carboxyl-functional polyester resin is 1000-40000, the acid value is in the range of 10-100mg KOH/g, and the glass transition temperature Tg is in the range of 40-80 ℃.

In the present invention, the weight average molecular weight of the carboxyl-functional polyester resin is preferably 1500-; the acid value is preferably in the range from 20 to 80mg KOH/g, more preferably from 20 to 40mg KOH/g; the glass transition temperature Tg is preferably from 45 to 65 ℃ and more preferably from 50 to 65 ℃.

In the present invention, the above-mentioned carboxyl-functional polyester resin may be formed by condensation of the corresponding dibasic acid and polyhydric alcohol; wherein the dibasic acid is terephthalic acid, isophthalic acid, 1, 4-cyclohexyl dicarboxylic acid, adipic acid, succinic acid, etc.; the polyhydric alcohol includes ethylene glycol, diethylene glycol, propylene glycol, hexanediol, neopentyl glycol, cyclohexyl dimethanol, trimethylolpropane, etc.

In the present invention, the above-mentioned polyester resins of carboxyl functionality are obtainable by commercially available routes, such as: SJ5122, SJ5101 and SJ4# ET of Anhui Shenjian, and Uralac P5200 and Uralac P5201 of DSM company. Such carboxyl-functional polyester resins are well known to those skilled in the art.

Preferably, the aliphatic dibasic acid has a structural formula shown in formula (I):

wherein x is an integer of 4 to 18.

In the present invention, the aliphatic dibasic acid is a saturated linear aliphatic dibasic acid, and preferably adipic acid, pimelic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, or the like.

Preferably, the aliphatic polyanhydride has a structural formula as shown in formula (II):

wherein y is an integer of 4 to 8, and z is an integer of 2 to 18;

preferably, the aliphatic polyanhydride has an acid value in the range of 250-400mg KOH/g and a melting range of 50-170 ℃.

The acid value of the aliphatic acid anhydride is preferably 300-350mg KOH/g, and the melting range is preferably 70-100 ℃.

In the present invention, the above-mentioned aliphatic acid anhydride can be obtained by a commercially available route, for example: of AllnexP791. Such aliphatic polyanhydrides are well known to those skilled in the art.

In the present invention, leveling agents (e.g., AHA1088P, etc.), deaerators (e.g., benzoin, etc.), and such additives are well known to those skilled in the art.

In the present invention, pigments and fillers include, but are not limited to, red iron oxide, yellow iron oxide, chromium pigments, carbon black, titanium dioxide, phthalocyanine blue, phthalocyanine green, azo, anthraquinone, thioindigo, precipitated barium sulfate, and the like.

Preferably, the raw materials comprise, by weight: 15-35% of epoxy group functionality composition, 53-84% of carboxyl group functionality composition, 0.5-0.6% of degasifier, 0-1% of flatting agent and 0-26% of pigment and filler.

In the invention, the preparation method of the GMA system powder coating with smooth moire texture effect comprises the following steps: mixing all the raw materials, hot melting, mixing, tabletting, pulverizing, and sieving. Wherein the mesh number of the screen for sieving is 80-120 meshes, preferably 100-120 meshes.

In the invention, the construction method of the GMA system powder coating with smooth moire texture effect comprises the following steps: the coating can be adhered to a substrate by electrostatic gun spraying, friction gun spraying, fluidized bed dip coating and the like, and then a coating film with smooth moire texture effect is formed by heating or radiation curing. The thickness of the coating film is 100-200 μm, preferably 110-150 μm.

The substrate according to the invention can be an uncoated substrate or a coated substrate which has already been coated.

The substrate with the coating is coated with a smooth powder coating.

The coating of the above coated substrate is a cured or partially cured powder coating.

The GMA system powder coating construction method with the smooth moire texture effect can also be used for adhering the transparent powder coating with the smooth moire texture effect on the substrate with the coating by a method of covering with light, such as electrostatic gun spraying, friction gun spraying, fluidized bed dip coating and the like, and then forming a coating film with the smooth moire texture effect in a heating or radiation curing mode.

Has the advantages that: the inventor accidentally finds that when GMA resin in the formula is partially replaced by epoxy resin or TGIC in the early ice flower texture research work, a moire texture plate with completely different ice flower effects can be obtained, and therefore the technical scheme of the invention is obtained. Compared with the standard TMMGU (1174) powder system which adopts a hydroxy polyester + amino resin curing system and is known in the prior art, the invention provides a novel GMA system powder coating with smooth moire texture effect, the raw materials of the GMA system powder coating contain an epoxy functionality composition, and the applicant finds that the GMA system powder coating can provide smooth moire texture after being used as a curing agent and subjected to crosslinking reaction with a carboxyl functionality composition; in addition, compared with the prior art that the viscosity of the system is increased by adding the pigment and the filler so as to be beneficial to obtaining the texture plate surface, the method can obtain the clear moire plate surface even if the pigment and the filler are not added. The powder coating does not contain a moire agent and can be prepared by a one-step extrusion construction process, the moire powder coating has a smooth moire texture effect after being cured, the moire texture is clear and uniform, the continuity is good, the moire is smooth in the interior, the decoration effect is obvious, and the reproducibility is good.

Drawings

FIG. 1 is a graph showing the effect of applying a GMA system powder coating having a smooth moire pattern effect prepared in example 2 of the present invention to a workpiece;

FIG. 2 is a graph showing the effect of applying GMA system powder coating having smooth moire pattern effect prepared in example 3 of the present invention to a workpiece;

FIG. 3 is a graph showing the effect of applying GMA system powder coating having smooth moire pattern effect prepared in example 7 of the present invention to a workpiece;

FIG. 4 is a graph showing the effect of applying GMA system powder coating having smooth moire pattern effect prepared in example 8 of the present invention to a workpiece;

FIG. 5 is a graph showing the effect of applying a GMA-based powder coating having a smooth moire pattern effect prepared in example 9 of the present invention to a workpiece;

FIG. 6 is a graph showing the effect of applying onto a workpiece a GMA-based powder coating having a smooth moire pattern effect prepared in example 12 of the present invention;

FIG. 7 is a graph showing the effect of applying onto a workpiece a GMA-based powder coating having a smooth moire pattern effect prepared in example 16 of the present invention;

FIG. 8 is a graph showing the effect of applying onto a workpiece a GMA-based powder coating having a smooth moire pattern effect prepared in example 19 of the present invention;

fig. 9 is a graph showing the effect of applying a GMA system powder coating having a smooth moire pattern effect on a workpiece, prepared in example 23 of the present invention.

Detailed Description

The technical solution of the present invention will be described in detail below with reference to specific examples.

Example 1

The substrate with the coating comprises the following raw materials in parts by weight: 295 parts of polyester resin with carboxyl functionality SJ4# ET, 22.5 parts of curing agent AHA6810, 1 part of carbon black, 5 parts of flatting agent AHA1088P, 3 parts of benzoin AHA4100 and 175 parts of precipitated barium sulfate.

The preparation method comprises the following steps: placing the above raw materials in a plastic bag, manually mixing for 3-5min, adding into a twin-screw extruder (model: SLJ-30A, Nicotiana tabacum), melting, homogenizing, tabletting, cooling, grinding into fine powder, sieving with 120 mesh sieve, respectively electrostatically spraying on a degreased cold-rolled steel plate, and solidifying at 200 deg.C for 15 min.

Example 2

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 360 parts of carboxyl polyester resin SJ4# ET, 68 parts of glycidyl group-containing acrylic resin AHA7700, 68 parts of epoxy resin E-12 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the raw materials are placed in a plastic bag and manually mixed for 3-5min, added into a double-screw extruder (model: SLJ-30A, Tokyo), melted and homogenized, tableted, cooled, ground into fine powder, sieved by a 120-mesh sieve, coated on the coated base plate obtained in example 1 in an electrostatic spraying mode, and solidified for 15min at 200 ℃.

Example 3

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 369 parts of carboxyl polyester resin SJ4# ET, 81 parts of glycidyl group-containing acrylic resin AHA7700, 54 parts of epoxy resin E-12 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 4

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 364 parts of carboxyl polyester resin SJ4# ET, 56 parts of glycidyl group-containing acrylic resin AHA7700, 84 parts of epoxy resin E-12, 5 parts of flatting agent AHA1088P and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 5

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 360 parts of carboxyl polyester resin SJ4# ET, 68 parts of glycidyl group-containing acrylic resin YH208, 68 parts of epoxy resin E-12 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 6

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 360 parts of carboxyl polyester resin SJ4# ET, 68 parts of glycidyl group-containing acrylic resin AHA7570, 68 parts of epoxy resin E-12 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 7

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 360 parts of carboxyl polyester resin SJ5122, 68 parts of glycidyl group-containing acrylic resin AHA7700, 68 parts of epoxy resin E-12 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 8

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 360 parts of carboxyl polyester resin CC @2441-2, 68 parts of glycidyl-containing acrylic resin AHA7700, 68 parts of epoxy resin E-12 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 9

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 380 parts of carboxyl polyester resin SJ4# ET, 64 parts of glycidyl-containing acrylic resin AHA7700, 54 parts of epoxy resin E-12, 5 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 10

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 383 parts of carboxyl polyester resin SJ4# ET, 64 parts of glycidyl group-containing acrylic resin AHA7700, 42 parts of epoxy resin E-12, 7 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 11

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 340 parts of carboxyl polyester resin SJ4# ET, 78 parts of glycidyl group-containing acrylic resin AHA7700, 78 parts of epoxy resin E-12, 5 parts of dodecanedioic acid and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 12

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 320 parts of carboxyl polyester resin SJ4# ET, 87 parts of glycidyl group-containing acrylic resin AHA7700, 87 parts of epoxy resin E-12, 10 parts of dodecanedioic acid and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 13

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 400 parts of carboxyl polyester resin SJ4# ET, 82 parts of glycidyl group-containing acrylic resin AHA7700, 12 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 14

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 395 parts of carboxyl polyester resin SJ4# ET, 93 parts of glycidyl group-containing acrylic resin AHA7700, 9 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 15

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 390 parts of carboxyl polyester resin SJ4# ET, 100 parts of glycidyl group-containing acrylic resin AHA7700, 7 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 16

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 415 parts of carboxyl polyester resin SJ4# ET, 72 parts of glycidyl group-containing acrylic resin AHA7700, 15 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 17

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 425 parts of carboxyl polyester resin SJ4# ET, 62 parts of glycidyl group-containing acrylic resin AHA7700, 18 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 18

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 350 parts of carboxyl polyester resin SJ4# ET, 75 parts of glycidyl-containing acrylic resin AHA7700, 75 parts of epoxy resin E-12, 3 parts of benzoin AHA4100 and 5 parts of polyanhydrideP791。

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Example 19

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 369 parts of carboxyl polyester resin SJ4# ET, 81 parts of glycidyl group-containing acrylic resin AHA7700, 54 parts of epoxy resin E-12 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

Example 20

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 380 parts of carboxyl polyester resin SJ4# ET, 64 parts of glycidyl-containing acrylic resin AHA7700, 54 parts of epoxy resin E-12, 5 parts of triglycidyl isocyanurate AHA6810 and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

Example 21

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 309 parts of a polyester resin with carboxyl functionality SJ4# ET, 58 parts of an acrylic resin AHA7700 containing glycidyl groups, 58 parts of an epoxy resin E-12, 3 parts of benzoin AHA4100, 3 parts of carbon black and 75 parts of precipitated barium sulfate.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

Example 22

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 320 parts of a polyester resin with carboxyl functionality SJ4# ET, 60 parts of an acrylic resin AHA7700 containing glycidyl groups, 60 parts of an epoxy resin E-12, 3 parts of benzoin AHA4100, 3 parts of carbon black and 50 parts of precipitated barium sulfate.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

Example 23

A GMA system powder coating with smooth moire texture effect comprises the following raw materials in parts by weight: 347 parts of a polyester resin with carboxyl functionality SJ4# ET, 65 parts of a glycidyl group-containing acrylic resin AHA7700, 65 parts of an epoxy resin E-12, 3 parts of benzoin AHA4100, 3 parts of carbon black and 25 parts of precipitated barium sulfate.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

Comparative example 1

A transparent polyester/GMA formula comprises the following raw materials in parts by weight: 123 parts of glycidyl group-containing acrylic resin AHA7700, 370 parts of carboxyl functionality polyester resin SJ4# ET, 5 parts of leveling agent AHA1088P and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Comparative example 2

A polyester/GMA formula comprises the following raw materials in parts by weight: 80 parts of glycidyl group-containing acrylic resin AHA7700, 240 parts of carboxyl functionality polyester resin SJ4# ET, 5 parts of leveling agent AHA1088P, 3 parts of benzoin AHA4100, 1 part of carbon black and 175 parts of precipitated barium sulfate.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

Comparative example 3

A transparent polyester/TGIC formula comprises the following raw materials in parts by weight: 460 parts of a carboxyl-functional polyester resin SJ4# ET, 35 parts of TGIC, 5 parts of a levelling agent AHA1088P, 1 part of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Comparative example 4

A polyester/TGIC formula comprises the following raw materials in parts by weight: 300 parts of polyester resin with carboxyl functionality SJ4# ET, 22.6 parts of TGIC, 5 parts of flatting agent AHA1088P, 1 part of benzoin AHA4100, 100 parts of titanium dioxide and 75 parts of precipitated barium sulfate.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

Comparative example 5

A transparent polyester/E-12 mixed system formula comprises the following raw materials in parts by weight: 345 parts of polyester resin with carboxyl functionality SJ4# ET, 148 parts of epoxy resin E-12, 5 parts of flatting agent AHA1088P and 3 parts of benzoin AHA 4100.

The preparation method comprises the following steps: the coating was applied to the coated substrate obtained in example 1 by electrostatic spraying as in example 2.

Comparative example 6

The formula of a polyester/E-12 mixed system comprises the following raw materials in parts by weight: 220 parts of polyester resin with carboxyl functionality SJ4# ET, 95 parts of epoxy resin E-12, 5 parts of flatting agent AHA1088P, 3 parts of benzoin AHA4100, 1 part of carbon black and 175 parts of precipitated barium sulfate.

The preparation method comprises the following steps: it was coated on the degreased cold rolled steel sheet by means of electrostatic spraying as in example 1.

The powder coatings prepared in examples 1 to 23 according to the invention and comparative examples 1 to 6 were tested for their properties.

Test item and method

1. Texture of moire

Expressed by visual observation.

2. Thickness of coating film

Measured directly with a magnetic thickness meter (thickness meter Q Nix4500 from Automation dr. Nix GmbH, germany).

3. Gloss of

The reflectance was measured directly at 60 ℃ according to GB/T1743-89 using Micro-gloss 60 ℃ 4442 from BYK, Germany.

Secondly, the raw material source

The suppliers of each raw material in examples 1 to 23 and comparative examples 1 to 6 are shown in table 1.

TABLE 1 suppliers of the respective raw materials

Third, the detection result

TABLE 2 results of the performance test of the coatings prepared in examples 2-23 and comparative examples 1-6

As can be seen from Table 2, the moire patterns obtained in examples 2-23 of the present invention are clear and uniform in texture, good in continuity, flat in the moire pattern, remarkable in decorative effect, and good in reproducibility. In comparative examples 1 to 6, the moire patterns could not be obtained by using only any one of the epoxy resin, triglycidyl isocyanurate, and glycidyl group-containing acrylic resin as the epoxy functional material.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and equivalent substitutions or changes according to the technical solution and the inventive concept of the present invention should be covered by the scope of the present invention.