JPS59230069A - Granular or powdery epoxy resin composition - Google Patents

Abstract

PURPOSE:The titled composition providing a film having improved weather resistance, consisting of an epoxy group-containing polyester resin obtained from a specific polyester carboxylic acid and a diepoxide compound, and a carboxyl group-containing resin. CONSTITUTION:The desired composition obtained by blending (A) a polyester resin having two or more epoxy groups at the ends prepared by reacting (i) a polyester polycarboxylic acid having 400-10,000 molecular weight, 10-300mg KOH/g acid value, and two or more carboxyl groups at the end with (ii) a diepoxide shown by the formula (R and R' are H, or lower alkyl) with (B) a solid resin having two or more carboxyl groups in one molecule in a ratio of number of carboxyl groups in the component B to number of epoxy groups in the component A of about 0.3-3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an epoxy powder resin composition that can form a coating film with excellent weather resistance.

More specifically, the terminal force μ of polyester polycarboxylic acid
By reacting one phoxyl group with 1 moμ of diepoxide having a specific structure, a polyester μ resin having an epoxy group at the end and a group at 11 is used. The present invention relates to a powder resin composition containing a solid resin having a phoxyl group.

In general, epoxy resins are widely used as components for powder coatings because they have excellent physical properties such as adhesiveness and chemical resistance, and do not generate by-product gas or gas during use.

For example, solid epoxy resins derived from the most typical epoxy resins, shrimp chlorohydrin and bisphenol/l/A, are currently used as powder coating components, but they must be completely cured. The resulting coating film is not necessarily satisfactory in terms of weather resistance, impact resistance, etc.

In addition, as a method for obtaining solid epoxy resin, for example, the terminal carboxylic acid of polyester polycarboxylic acid
A method is known in which a low molecular weight bifunctional epoxy resin is added to the base, but in this reaction, a polymeric resin in which polyester polycarboxylic acid and epoxy resin are alternately bonded is produced, and the product is However, if it is used as a powder coating, it may cause gelation, or even if it does not cause gelation, it may contain unreacted epoxy resin and have a wide molecular weight distribution. There was a problem with the appearance of the painted film surface being poor.

The present inventors investigated epoxy resin components for powder coatings with excellent weather resistance, and found that when polyester polycarboxylic acid is reacted with diepoxide having a specific structure, the formation of high molecular weight resin can be avoided. Therefore, the terminal power of polyester polycarboxylic acid (epoxy) V
It has been found that a solid resin to which 1 mole of diepoxide is added per group is extremely useful as a component for powder coatings, and as a result of further studies, the present invention has been arrived at.

That is, the present invention provides (a) a molecular weight of 400-10.000 and an acid value of 1;
0 to 300 Da KOH/f, polyester polycarbonate having two or more force μ boxy μ groups at the end (wherein R and B′ are the same or different and represent a hydrogen atom or a lower aμ group) A polyester μ resin having at least two or more epoxy groups at the end obtained by reacting with a diepoxide represented by (b) a solid resin having two or more force μ boxy μ groups in one molecule. This is a powder resin composition in which the number of epoxy groups in component (a) is approximately 0.3 to 3 relative to the number of poxy μ groups in component (b).

The component (&) used in the present invention has a molecular weight of 400-1
0,000 and the acid value is 10-300! One carboxyl group of a polyester polycarboxylic acid (hereinafter simply referred to as polyester polycarboxylic acid) having two or more carboxy μ groups at the terminals of KOH/g, the general formula (wherein R and IR' are the same or jepoxide 1, which is differentiatingly represented by a hydrogen atom or a lower aμ
It can be manufactured by adding moμ. The reaction for adding jepoxide is carried out by mixing and heating both raw materials. The heating temperature depends on the melt viscosity of the polyester polycarboxylic acid, but is usually 80°C.
~230'C, preferably 130-200'
It is C.

Although this reaction proceeds without the use of a catalyst, it is usually carried out using, for example, benzyldimethylamine, 2,4.6-tris(dimethylaminomethy/I/)pheno-/L'.

Tertiary amines (or salts thereof) such as 2-ethyl/l/-4-methyimidazo-μ, quaternary ammonium compounds such as triammonium phenotate, or e.g. sodium hexanetriozutate, etc. By using a catalyst such as an alkali metal alcoholade, the reaction can proceed more smoothly. The amount of these catalysts used is 0.0 based on the total weight of the above two raw materials.
1 to 1 weight fi% is suitable. Furthermore, if necessary, there is no problem in carrying out the reaction in a solvent such as methane, ethyl glycol acetate, butyl acetate, etc. In this case, the bath agent may be concentrated and removed after the reaction. The reaction time may be precipitated in a non-solvent.The reaction time is usually 10 minutes to 5 hours, depending on whether a catalyst is added or not.

The amount of raw materials used is theoretically such that the number of epoxy groups in the diepoxide is 2 relative to the number of Vp groups in the polyester polycarboxylic acid, but in actual reactions it is approximately 1.5 or more. , preferably in the range of about 1.8 to 4. If excess dieboxide is used, it may be removed after the reaction, for example, by extraction or vacuum distillation. In addition, polyester polycarboxylic acid is a combination of polybasic acid or its anhydride and polyhydric alcohol.
It is a well-known resin that can be produced by a conventional method using as a raw material. Examples of polybasic acids include tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, methyl-hexahydro-7ter-mu acid, maleic acid, and 7-mer μ-acid.

Succinic acid, glycolic acid, adipic acid, azelaic acid, sepacic acid, decanedicarboxylic acid, hepatic acid, terephthalic acid, isophthalic acid, trimellitic acid, etc. can be mentioned, and these polybasic acids ( or anhydrides thereof) may be used.

Examples of the polyhydric alcohol-μ include 1,4-cyclohexanedimethanol yv+1.4-yy lohexanedioe μ, hydrogenated bisphenol/l/A, spiroglyco-μ,
Ethyl L' glycol A/, propylene glyco-μ, gtylene glycol/I/, hexylene glyco-〃, decanedio μ, neopenty μ glycol, glycerin, trimethylo=lv propane, hydroxypipalic acid neobenchi μ glycol ester, bispheno- 1vA, etc., and mixtures of these polyhydric alcohols may also be used.

Various polyester polycarboxylic acids can be produced by appropriately combining these polybasic acids (anhydrides thereof) and polyhydric alcohols.

Among such polyester polycarboxylic acids, particularly preferred are those having 2 to 4 force μ boxy μ groups at the end, a donor weight of 800 to 4000, and an acid value of 50 to 50.
It has 2009KOH/f.

Furthermore, as the jepoxide represented by the general formula (1), R'+ I? Examples of lower alkyl μ represented by / include jepoxides such as methi μ and ethyl μ, specifically, for example, vinyl cyclohexene dioxide (11?, R′ is both water Xi).

Examples include limonene dioxide (both R and R' are methi/I/).

The polyester μ resin (resin) having at least two or more epoxy groups at the end produced by the method described above is a solid resin having an epoxy fij of 1300 to 500 (1). ) Even if heated for a long time (10 to 20 hours), it is stable without any quality change such as thickening.

Next, component (b) used in the present invention will be explained.

The solid resin (b) having two or more poxy groups in one molecule is, for example, one having two or more poxy groups, a molecular weight of 400 to 10,000, and an acid value of 10. ~30
Polyester μ resin with 05IyKOH/y and a melting point of 50 to 200°C, power of hydrolyzed ethylene/vinyl acetate copolymer Poki V/L/modified product (HE'1-C)
, ethylene and acrylic monomers (e.g. acrylic μ
A copolymer (EAA) containing a force μ boxy μ group obtained by copolymerizing with an acrylic monomer (acrylic acid, methacrylic acid, etc.), and a copolymer containing a force μ boxy μ group obtained by polymerizing an acrylic monomer. Examples include acrylic resin.

As the polyester μ resin, for example, the polyester polycarboxylic acid described in component (a), or the polyester μ polyol-μ, such as phthalic anhydride, succinic anhydride, maleic anhydride, hexahydrophthalic anhydride, etc. For example, the terminus can be modified into a μboxyμ group by addition of an acid anhydride. HEVA-C has a hydrolysis rate of 10-100% and a vinyl acetate μ content of 10-100%.
50% by weight, melt index (M) 1-500F
/ 10 min of hydrolyzed ethylene/vinyl acetate copolymer (HEVA) with μ boxy μ group-containing vinyl μ monomers (e.g. acrylic acid, methacrylic acid.

maleic acid) or acid anhydrides (e.g. succinic anhydride, maleic anhydride, zuma-μ acid anhydride, citraconic anhydride, itaconic anhydride, diconic anhydride, methic anhydride ,
Chlorendic anhydride, phthalo-μ acid anhydride, hexahydrophtha-μ acid anhydride, tetrahydrophthalo-μ acid anhydride, methi-μ anhydride
Modified products obtained by adding aliphatic, alicyclic, or aromatic acid anhydrides such as hexahydro-7-teracic acid, anhydrous methyμ-tetrahydrophthalic acid, or methylhimic acid anhydride are Those having a body acid value of 10 to 150 can be used.

As FAA, an acrylic acid content of 1 to 20% and a M process of 1 to 500 f/10 min (D can be used.As an acrylic resin containing a force μ boxy μ group, an acrylic Acid, methacrylic acid, acrylic acid-
2-Hydroxyethyl.

Examples include copolymerization of methacrylic acid methyl/L', ethyl methacrylic acid, styrene, vinyl chloride, vinyl acetate, acrylonitrium, etc., and their acid value is 1.
0-300 qKOH/II and melting point 50-20
A temperature of 0°C can be used.

Components (a) and (b) in the resin composition of the present invention are such that the ratio of the number of power μ-pokin μ groups in component (b) to the number of power μ-pokin μ groups in the component color is approximately 0, 3 to 3, preferably 0.8 to 1.2.

In addition to components (a) and (b), the resin composition of the present invention contains fillers, leveling agents, antifoaming agents, surfactants, antiblocking agents, antioxidants, It can contain pigments, dyes, curing catalysts, etc.

The granular resin composition of the present invention can be prepared using a conventionally known method. For example, after adding various additives as necessary to component (a) and components], these are melt-kneaded using an extruder. A granular resin composition can be obtained by pulverizing the obtained mixed material with a pulverizer or freeze-pulverizing it. In addition, heating low μ
After mixing, it may be crushed. Further, each component may be dissolved or dispersed in a solvent and mixed, and then pulverized by spray drying or freeze drying, or pulverized after removing dissolved substances under reduced pressure and heating. Furthermore, each component can be powdered and mixed to form a powder composition. The particle size of the powder after pulverization is usually 5 to 500 microns. The resin composition of the present invention can also be used as granules. Such granules can be produced using a granulator, and the particle size is usually 1 to 10.

A method known per se can be used to apply the granular resin composition of the present invention to the surface of an object to be coated or an adherend. For example, electrostatic powder coating equipment, electric field curtain type powder coating equipment,
It can be applied using a hot-medium applicator or the like. Further, a coating film can also be formed using a fluidized dipping method or a thermal spraying method.

After painting, a hardened film is formed by heating in a heating furnace. The baking curing temperature is usually 100 to 220° C. at the temperature of the object to be coated, and the time is about 10 to 120 minutes, although it depends on the presence or absence of a catalyst. Furthermore, when baking at a high temperature, the baking time can be shortened.

The powder resin composition according to the present invention is useful for coating or adhering various materials such as metal, glass, concrete, cefmic, tiles, etc.

In particular, the coating film made from the composition of the present invention has excellent weather resistance as well as excellent physical properties in terms of adhesion, chemical resistance, and water resistance.
Guardley μ, coatings for outdoor play equipment, fences, etc., anti-corrosion resin linings for iron pipes, anti-rust coatings for steel frames, sealing of electrical parts, adhesives, etc.
It is particularly suitable as an impregnating agent.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 Neoplier μ glycol/l/7 mol + Futa μ acid anhydride 4
Polyester polycarboxylic acid (m,
p90-95℃, acid value 62.4, molecular weight 1800) 90
Add 140i of vinyl cyclohexene dioxide while maintaining 0F at 180°C, and react at 185°C for 1 hour to form a solid polyester μm1 resin having epoxy groups.
, p 90-95°C1 acid value 3.8, epoxy equivalent 1
,035) was obtained. Neopentyl glyco-/'5 mol, (limethyl-propane 2
mol, polyester polyester obtained by reacting 7-μ acid fimol < acid value 2.3.0H (iI
li73.6, molecular weight 1560) and phthalic anhydride 4m
Polyester resin (m, p 95-100°C, acid value 52.5) with a poxy-μ group at the terminal obtained by addition reaction of 01 (Of, 300 g of titanium oxide, Modaflow 10F and imidazo-/ I/3f/ was added and melt-mixed, and the molten mixture was pulverized to obtain a powdered resin composition (particle size: 100 mesh).This powdered resin composition was coated with an electrostatic powder coating machine (model GEMA 720). ) was applied electrostatically onto an iron plate, and then cured in a baking oven at 190°C for 20 minutes.

Table 1 shows the physical properties of the obtained film.

Example 2 Ethylene/vinyl acetate copolymer [vinyl acetate μ content 28%, melt index (M) 400g/10m
1n) hydrolyzate (saponification rate 90%, M process 200)
100F was dissolved in 200 g of xylene, and 13.5 g of anhydrous hexahydro-7 tar acid was added thereto to give a solution of 100 to 10
The reaction was carried out at 5°C for 60 minutes. Then add 500g to the reaction solution.
Methanol and V were added to precipitate the reaction product, and the precipitate was filtered and dried under reduced pressure to obtain a modified HEVA (HEiVA-C) (M process 140, acid value 37°4). ).

On the other hand, a polyester polycarboxylic acid (m, p 110-115°C, acid Price: 86.0
, molecular weight 1270) While keeping 652F at 185°C, add vinyl cyclohexene dioxide 1401,
Polyester resin having solid epoxy groups by reacting at 90℃ for 1 hour (m, p 105-110℃, acid value 4
．． 9, epoxy equivalent weight 785) was obtained.

Power! 54f of polyester resin with epoxy group for 100g of boxy μ modified product! and titanium oxide 20F were added, melted and mixed, and then frozen and crushed.

A powdered resin composition (particle size, +00M) was obtained. This powdered resin composition was coated with an electrostatic powder coating machine (model GEMAT20).
The coating was electrostatically coated on an iron plate using a varnish, and then cured in a baking oven at 200°C for 20 minutes.

Table 1 shows the physical properties of the obtained film.

Example 3 40 parts of styrene, 30 m of methyl methacrylate, 17.2 parts of n-butyl acrylate, and 12.8 parts of acrylic acid.
To 55 parts of acrylic μ resin with an acid value of 100 and a melting point of 113°C obtained by copolymerizing 55 parts of polyester resin with an epoxy group obtained in Example 1, 50 parts of titanium oxide, and 1 part of Modaflow were added. Melt mix and grind to obtain powdered resin composition (particle size: +00M)
I got it. This powdered resin composition was electrostatically coated onto an iron plate using an electrostatic powder coating machine (model GEMA720), and then baked at 200'C for 15 minutes.

Table 1 shows the physical properties of the obtained film.

Example 4 Ethylene/acrylic acid copolymer EAA from Dow Chemical Company
435 (M, T 11., O, acid a27) 100
40 parts of the epoxy group-containing polyester resin obtained in Example 2 were melt-mixed and freeze-pulverized to obtain a powdered resin composition, 48 M>. This powdered resin composition was coated onto an iron plate using a fluidized dipping method and then baked at 200°C for 15 minutes.

Table 1 shows the physical properties of the obtained film.

Table 1 Procedural Amendment (Voluntary) 1985 July Oni? Day 2, Name of the invention: Epoxy powder/granule resin composition 3, Relationship with the amended person's case Patent applicant address: 2-27 Doshomachi, Higashi-ku, Osaka Name (
293) Takeda Pharmaceutical Co., Ltd. Representative Hayashi Kura
Iku 4 Department 4, Agent address: 2-17-85 Jusanhonmachi, Yodoyo-ku, Osaka, Tokyo Contact information (Patent Laws and Regulations Division) Telephone: 278-2219, 2-5, Details of the invention in the specification to be amended W ! B, Contents of correction s Page 11, lines 10-11, ``The force of component (b) μ boxy for the number of groups μ pokin! of the group...
・" is corrected to ``For the number of epoxy groups in component (&) for the force μpoki V/I/number of groups in minute (b)...''.

that's all

Claims (1)

[Claims] One molecular weight is 400 to 10,000, and the acid value is 10 to 10.
300111/KOH/f Polyester polycarboxylic acid having ter, K terminal K 2 or more groups, and represented by the general formula (wherein R2y is the same or different and represents a hydrogen atom or lower alkyl) A polyene teμ resin having at least two or more epoxy groups at the end obtained by reacting with diepoxide and a solid resin having two or more phoxyl groups in the molecule are combined with the component (
A granular resin composition blended so that the number of epoxy groups in b) is 110.3 to 3.