CA2346963C - Thermosetting powder coating systems - Google Patents
Thermosetting powder coating systems Download PDFInfo
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- CA2346963C CA2346963C CA002346963A CA2346963A CA2346963C CA 2346963 C CA2346963 C CA 2346963C CA 002346963 A CA002346963 A CA 002346963A CA 2346963 A CA2346963 A CA 2346963A CA 2346963 C CA2346963 C CA 2346963C
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D167/00—Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Coating compositions based on derivatives of such polymers
- C09D167/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
Abstract
The present invention concerns thermosetting powder coating systems based on carboxyl-functional polyester resins, .beta.-hydroxyalkylamides and/or polyepoxides, as well as optionally ordinary pigments, fillers and additives, their production and use, protective layers from them and objects provided with such protective layers. The invention also concerns polyester resins that are suitable for formulation of thermosetting powder coating systems. The polyester resins have an acid number from 15 to 70 mg KOH/g, a hydroxyl number of a maximum of 10 mg KOH/g, and a glass transition point of at least 35°C. These polyester resins contain up to 80 mol%, in reference to the total amount of all employed dicarboxylic acids, isophthalic acid and 0.5 to 30 mol%, in reference to the total amount of all employed diols, 1,5-pentanediol and/or at least one 1,5-pentanediol provided with at least one alkyl substituent and/or at least one 3-oxa derivative of the aforementioned diol.
Description
Thermosetting Powder Coating Systems The invention concerns thermosetting powder coating systems based on carboxyl-functional polyester resins with a functionality of 2 and from the group of selective organic compounds that are capable of reaction with the carboxyl groups of the polyester during formation of a covalent bond, selected crosslinking agents, as well as optional suitable pigments, fillers and additives, their production and use, as well as protective layers made from these coating systems. The invention also concerns polyester resins that are suitable for formulation of thermosetting powder coating systems. 'The invention also concerns a method for production of thermosetting powder coating systems, as well as the use of the thermosetting powder coating system to produce coatings and protective layers by fluidized-bed coating, and electrostatic coating.
Since the 1970s, coating powders based on a carboxyl-functional polyester resin and the polyfunctional epoxy compound triglyci'ldyl isocyanurate (TGIC) have been considered the industry standard for production of weatherproof coatings in fagade construction, in automobile accessories, and general industrial applications. For example, DE 26 18 729 describes polyester resins with acid numbers from 50 to 100 mg KOH/g of polyester for such formulations.
An important reason for the technical supremacy of any coating powder system lies in the chemical nature of the crosslinking reaction. Since an addition reaction between the oxirane and carboxyl groups of the binder partners is involved, no cleavage products are liberated, which is advantageous for the optical appearance of the stoved coatings with higher layer thickness, but also for the environment.
Beginning a few years ago, the toxicological risk of coating powders containing TGIC
was increasingly discussed, was and is an incentive to search for epoxy-functional but also other alternative products. Although TGIC and TGIC-containing coating powder has had to be marked accordingly since then in many countries of Europe and elsewhere because of the mutagenic potential of this curing agent, it is still tiue that a substitute for TGIC
that is technically equivalent in all respects is presently not available.
Among other things, (3-hydroxyalkylamides, like Primid XL-552 (bis[N,N'-di((3--hydroxyethyl)]adipamide) or Primid QM-1260 (bis[N,N'-di((3-hydroxypropyl)]adipamide), both from EMS Chemie, are now offered as alternatives to TGIC as a curing agent for carboxyl-functional polyester resins. A special feature of these curing agents lies in their complete toxicological acceptability according to the present state of knowledge. EP 0 discloses (3-hydroxyalkylamide-group-containing polyesters that represent polymers of similar functionality and applicability.
21757-'81 Additional posslble. alternatives to TGIC as curing agents for carboxyl-functional polyester resins include thtt glycidyl esters of aromatic or cycioaliphatic dicar"boxyiic acids, see EP 0 110 ^-, 50 E l; a corresponding commercially available curing agent of similar chemical structure is Araidit~a~ PT 910 (terephthalic acid dialycidyl ester/trimellitic acid triglycidyl ester, about 75:25) from CBA Spezialitatenchemie GmbH. The presence of the trifunctional trimellitic acid ester in Araldit~~% PT 910 is dtemed advantageous for the crosslinking density of the stoved :,oatings in comparison with pure diglycidyl esters. Another possibility is offered by trie use of po,.idized oils, see EP 0 600 546 Al; binder systems of this type are offered by DS1A
Resins under the name Uranox . Another potential alternative is a polyepoxide very similar to TGIC, tris-((3-methylglycidyl) isocyanurate, see WO 96/17026. Polymer epoxides are also known as epoxide curing agents.
All the mentioned products are now gaining increasing significance in the formulation of coating powders from carboxyl-functional polyester resins, but in which TGIC
can still claim numerous markets.
Polyester resins for production of weather-stable coating powders, which are cured with polyepoxide and/or P-hydroxyalkylamide, have an acid number in the range from 15 to 70 mg KOrUg of polyester and a hydroxyl number less than or equal to 10 mg KOH/g of polyester and essentially consist of units of aromatic dicarboxylic acids, like terephthalic and isophthalic acids, in addition to which limited amounts of aliphatic and/or cycloaliphatic dicarboxylic acids also find application, like adipic and/or cyclohexanedicarboxylic acid, and aliphatic diols and preferably branched ones, like neopentyl glycol, in addition to limited fractions of linear and/or cycloaliphatic diols. The coemployment of hydroxycarboxylic acids that are functional derivatives, like their inner esters (lactones), is also possible.
Modification of such resins by using dimeric and trimeric fatty acids is also lmown. Limited amounts of trifunctional or higher functional and optionally monofunctional compounds can also be used.
It is now being observed that a generally more or less strongly pronounced phenomenon in coating powders, namely that of physical aging, also occurs, generally strongly, in those that are formulated from carboxyl-functional polyester resins and polyepoxides, and even more strongly in those formulated from carboxyl-functional polyester resins and (3-hydroxylalkylamides. Physical aging is expressed, among other things, in a distinct reduction of flexibility of the stoved coatings over days and weeks and, depending on the employed system, even when the coated and stoved parts are stored under normal climatic conditions (23 C, 50% relative humidity), as presented in detail and clearly in DE 44 01 438 Al.
The above application discloses that coating powders whose binder consists of a) more closely defined linear carboxyl-functional polyester resins and b) P-hydroxyalk-ylamide andJor polyfunctional epoxy compounds experience no recordable degradation of flexibility as a result of physical aging if the percentage of isophthalic acid in the polyester resins in reference to the total amount of employed dicarboxylic acids does not exceed 10 mol%. By means of such formulations, the high mechanical requirements that are imposed, for example, in precoating metal and coil coating technology as a result of later deformation of the coated parts can be satisfied in coating powders.
However, it has been shown that the coatings with respect to their resistance to rapid weathering in the Q-panel accelerated weathering test according to ASTM G 53-77 do not reach the level that is now generally required in coating powders for fagade applications according to the examples disclosed in DE 44 01 438 Al.
DE 40 12 020 Al discloses a method for coating of substrates with thermosetting coating powder preparations at high temperature and short times. Such coating powder and preparations consist of A) carboxyl-functional polyester resin, B) a compound capable of reaction with the carboxyl groups and C) ordinary additives.
The polyester resins A) that cont:ain hydroxyl groups can include two or more carboxyl groups per molecule and have an acid number from 10 to 70 and a hydroxyl number from 0 to 40 with the stipulation that the hydroxyl number is always lower than the acid number.
Oxirane compounds with two or more epoxide groups per molecule, in which triglycidyl isocyanurate, bisphenol glycidyl ether and/or its higher homologs are included, are disclosed as curing agent B).
Specifically, however, coemployment of compounds with the functionality greater than 2, stating a minimum fraction of 1 mol%, referred to the total formulation of the employed components A) and B) is referred to in particular. Thus, the use of significant amounts of trifunctional components trimethylpropane [sic] and trimellitic acid anhydride is disclosed in all the examples.
US 5 262 510 A discloses thermosetting coating powder masses that are obtained by a combination of a polyester resin with at least four reactive carboxyl groups per molecule with an epoxy resin based on bisphenol A diglycidyl ether.
Aliphatic or alicyclic alcohols with 2 to 3 reactive groups and 2 to 6 carbon atoms and aliphatic, alicyclic or aromatic carboxyli'lc acids with 2 to 4 carboxyl groups and 4 to 12 carbon atoms are then mentioned as monomers to produce the polyester resin. 1,5-Pentanediol without further specification of its purpose is also mentioned in the overall disclosure of US 5 262 510 A
among the alcohols with two reactive groups.
DE 43 35 845 discloses that coat:ing powder masses made from polyester resins with an acid number from 15 to 75 mg KOH/g polyester, in which isophthalic acid makes up at least 80 mol% of the total amount of all the employed dicarboxylic acids, and at least (3-hydroxy-alkylamide as curing agent exhibit extraordinarily high resistance in the rapid weathering test with UVB exposure.
EP 0 389 926 B1 discloses that coating powder masses made from polyester resins with an acid number from 15 to 70 mg KOH/g of polyester with at least 75 mol%
isophthalic acid, in reference to the total amount of all employed dicarboxylic acid, and triglycidyl isocyanurate as curing agent, have extraordinarily high resistance in the rapid weathering test with UVB
exposure.
However, it is known, on the other hand, that a weak point in coating powder masses with high percentages of isophthalic acids is precisely the flexibility and it is quite impossible in numerous color shades to appropriately deform the coated objects (even right after stoving) without damaging these paint layers (at least on their surface).
EP 0 389 926 B1 proposes the coemployment of resin raw materials with a functionality greater than 2 in a total molar amount of a maximum of 8% in coating powder masses based on carboxyl-functional polyester resin with, at least 75 mol% isophthalic acid as acid component and triglycidyl isocyanurate, which simultaneously have as objective the highest weather resistance with the best possible flexibility. Moreover, this patent offers hints that the use of isophthalic acid in comparison with terephthalic acid (in general) results in inadequate impact strength. The same is also true for the powdered coating masses disclosed in DE 43 35 845 C2 in which (3-hydroxyalkylamides are contained as curing agents.
A high percentage of terephthalic acid as the aromatic dicarboxylic acid is deemed essential to achieve high mechanical properties for carboxylated polyester resin in GB 2 189 489 A.
The formulation disclosed in the Comparative Example of DE 44 01 438 Al does provide the resistance to rapid weathering requil-ed in European fagade construction, but not the required resistance to physical aging according to the values presented in the tables of this unexamined patent application with their detrimental consequences for deformability of the coating.
The manufacturers of fagade elements who operate according to the rational precoating metal or coil coating technology therefore do not have coating powder masses from carboxyl-functional polyester resins and polyepoxides (because of the cleavage product-free nature of their crosslinking reaction) or coating powder masses from carboxyl-functional polyester resins and (3-hydroxyalkylamides (because of their full toxicological acceptability according to the present state of knowledge), which impart the weather resistance to the fagade parts being subsequently deformed that is considered the standard nowadays for fagade construction.
With respect to the high degree of environmental compatibility, which characterizes coating powders over other coatings, this is an unsatisfactory circunlstance, since the solvent-containing coatings available as alternatives require removal of the emissions for ecological reasons by costly afterburning and/or filter systems from the exhaust of the operations that process such coatings systems, which creates costs and burdens the environment.
According to the invention there is provided a coating powder formulation consisting of at least one a) carboxyl-functional polyester resin, at least b) crosslinking agents chosen from the group of organic compounds that are capable of reaction with the carboxyl groups of the polyester to produce a covalent bond, and c) ordinary additives as well as optional pigments and fillers in which the a) polyester resin has an acid number from 15 to 70 mg KOH/g of polyester resin and a hydroxyl number of 10 or less mg KOH1g polyester resin and consists of dicarboxylic acids, diols and optionally hydroxycarboxylic acids, said coating powder formulation being characterized by the fact that the polyester resin contains a maximum of 80 mol% isophthalic acid, referred to the total amount of dicarboxylic acid, at least 20 mol% of at least one other dicarboxylic acid of the group of aromatic dicarboxylic acids with 8 to 16 carbon atoms and/or aliphatic dicarboxylic acids with 4 to .22 carbon atoms and/or cycloaliphatic dicarboxylic acids with 8 to 16 carbon atoms and/or dimerized fatty acids, in reference to the total amount of dicarboxylic acids, with the stipulation of a glass transition point of at least 35 C, at least 50 mol% of at least one branched aliphatic diol with 4 to 12 carbon atoms, which can also contain an ester group, a maximum of 50 mol% of at least one linear aliphatic diol with 2 to 22 carbon atoms and/or at least one cycloaliphatic diol with 6 to 16 carbon atoms, in reference to the total amount of diols, with stipulation of a glass transition point of at least 35 C, in which the mentioned diols include 1,5-pentanediol and/or at least one 1,5-pentanediol provided with one or more side alkyl substituents, like 3-methyl-1,5-pentanediol in a total molar amount from 0.5 to 30%, referred to the amount of all diols.
A dimerized fatty alcohol is optionally additionally contained as a diol.
1,5-Pentanediol.is preferably used.
5a In one aspect, the invention provides a coating powder formulation, comprising: (a) at least one carboxyl-functional polyester resin with an acid number of from 15 to 70 mg KOH/g of the polyester resin, a hydroxyl number of 10 or less mg KOH/g of the polyester resin and a glass transition temperature of at least 35 C, wherein: (i) the polyester resin composed of difunctional monomers comprises at least one dicarboxylic acid and at least one diol monomer, (ii) the polyester resin contains a maximum of 80 mol% of isophthalic acid relative to the total amount of all dicarboxylic acids, (iii) the polyester resin contains at least 20 mol% of at least one dicarboxylic acid selected from the group consisting of an aromatic dicarboxylic acid with 8 to 16 carbon atoms, an aliphatic dicarboxylic acid with 4 to 22 carbon atoms, a cycloaliphatic dicarboxylic acid with 8 to 16 carbon atoms, a dimerized fatty acid and a mixture thereof, relative to the total amount of all dicarboxylic acids, (iv) the polyester resin contains at least 50 mol% of at least one branched aliphatic diol with 4 to 12 carbon atoms, a maximum of 50 mol% of at least one diol selected from the group consisting of a linear aliphatic diol with 2 to 22 carbon atoms, a cycloaliphatic diol with 6 to 16 carbon atoms and a mixture thereof, relative to the total amount of all diols, and (v) the polyester resin contains among the diols 1,5-pentanediol or 1,5-pentanediol with one or more side alkyl substituents at a total molar concentration of from 0.5 to 30% relative to the amount of all diols present; and (b) at least one organic compound curing agent which reacts with the carboxyl groups of the polyester resin to produce covalent bonds.
The glass transition point is preferably at least 40 C and especially at least 45 C.
= 21757-181 5b The coemployment of hydroxycarboxylic acid or their functional derivatives is naturally also possible, like their inner esters (lactones). Likewise, instead of carboxylic acids, their functional derivatives, like esters or optionally anhydrides, can be used. Polyhydric alcohols containing vicinal hydroxyl groups can be substituted by corresponding epoxide compounds.
,6-Hydroxyalkylamide or polyepoxides are used as curing agents.
Preferably 5 to 30 mol% isophthalic acid is used.
The surprising thing of the present invention is the entirely unexpected effect according to which, by coemployment of a,w-diols that have five carbon atoms in sequence between hydroxyl groups, the coating powders with more than 10 mol% isophthalic acid in reference to the total amount of dicarboxylic acids used duririg formulation of the polyester not only exhibit the resistance to the physical aging that is inherent to the coating masses according to the prior art disclosed by DE 44 01 438 Al, whose polyester component has an isophthalic acid percentage of at most 10 mol% in reference to the total employed dicarboxylic acid, but, in addition, they have a significantly improved resistance to rapid aging of the Q-panel accelerated weathering test according to ASTM G 53-77.
It must be deemed quite particularly surprising that this unexpected effect occurs clearly as a result of coemployment of a,co-diol.s that have five carbon atoms in sequence between the hydroxyl groups even at a percentage of 0.5 mol%, in reference to the total amount of the employed diol, as demonstrated by the corresponding examples and Comparative Examples.
Previous experiments were unsuccessful to stabilize against physical aging coating powders from (3-hydroxyalkylamides, like Primid XL-552 and carboxyl-functional polyester resins that have an isophthalic acid percentage of more than 10 mol% in reference to the total amount of employed carboxylic acids, by coemployment of resin raw materials whose flexibilizing action on the coating powders has been repeatedly demonstrated (see for example, the practical example in DE 43 35 845 C2, which discloses 1,4-cyclohexanedicarboxylic acid, adipic acid or 1,6-hexanediol alone or in combination) or in DE 44 01 438 Al (here adipic acid and/or 1,4-cyclohexanedicarboxylic aciii are disclosed), as demonstrated by Comparative Examples C and D.
Previous experiments failed to stabilize, against physical aging, coating powders made from a polyepoxide, like triglycidyl isocyanurate and carboxyl-functional polyester resins that contain an isophthalic fraction of more than 10 mol%, in reference to the total amount of employed dicarboxylic acid by coemployment of resin raw materials with flexibilizing action on the coating powders, as suggested, for example, according to EP 0 110 450 B1 by means of adipic acid and 1,6-hexanediol in combination or according to DE 44 01 438 Al by adipic acid and/or 1,4-cyclohexanedicarboxylic acid.
DE 44 01 438 Al does disclose the use of at least 50 mol fractions (in reference to the total amount of employed diols) and at llast one branched aliphatic diol with 4 to 12 carbon atoms, which can also be understood to include 3-methyl-l,5-pentanediol, as well as the possible coemployment of at least one linear aliphatic diol with 2 to 22 carbon atoms, which also includes 1,5-pentanediol. However, there are no indications of the special suitability of these raw materials for achieving increased resistance against physical aging (despite a higher percentage of isophthalic acid) in addition to improved resistance to rapid weathering based on increased fractions of isophthalic acid.
Very good results are obtained from the coemployment of 5.8 mol% 1,5-pentanediol in reference to the total amount of all employed diols, in a polyester that contains, among other things, 13.6 mol% isophthalic acid in reference to the total amount of employed dicarboxylic acid and is formulated with triglydicyl isocyanurate or Primid XL-552 to a coating powder. In addition to the corresponding resistance to loss of flexibility as a result of physical aging, coating powder masses of this composition after stoving provided very good resistance to rapid weathering during UVB exposure. The excellent flow and luster of the coatings also merit special emphasis. Excellent results are also obtained if 3-methyl-1,5-pentanediol is used instead of 1,5-pentanediol. It is particularly surprising that, when 1,6-hexanediol was used instead of 3-methyl-1,5-pentanediol (despite the same molecular weight of two raw materials), the formulation with 1,6-hexanediol exhibits drawbacks with respect to flexibility after storage, although a higher contribution to flexibilization of the coating could be expected from an unbranched chain of six carbon atoms than from a chain of five carbon atoms with a side methyl group. Considerations of this type are also set forth in the brochure IP-70 of Amoco Chemical Corporation (How Ingredients I.nfluence; Unsaturated Polyester Properties), page 20, first section, second paragraph.
Naturally, it is possible within the context of the present invention, by expedients used according to the prior art, to improve the mechanical properties of coating powder films with respect to flexibility and/or weather resistance stabilized against physical aging by the coemployment, according to the invention, of (substituted) 1,5-pentanediol(s) and/or substituted 3-oxa- 1,5-pentanediol(s).
Very good flow in addition to higher resistance to physical aging and very good weather resistance were found in our own expen.ments in a formulation that contains, in addition to 13.6 mol% isophthalic acid, in reference; to the total amount of employed dicarboxylic acids, 4.5 mol% 1,5-pentanediol and 3 mol% :3-methyl-1,5-pentanediol, in reference to the total employed diols, and also 0.4 mol% trimethylolpropane, in reference to the total amount of all employed raw materials.
Formulations produced according to the invention (using 1,5-pentanediol and/or 3-methyl-1,5-pentanediol) with a molar fraction of terephthalic acid >85% as well as an isophthalic fraction <10%, in reference to the total amount of all employed dicarboxylic acids, were, in comparison with the two examples mentioned from DE 44 01 438 Al, still very readily deformable in the reserve impact test in the cooled state, whereas they were not inferior to these compounds in the Q-panel accelerated vveathering test according to ASTM G 53-77. The resins so formulated therefore do lie formally within the scope of disclosure of DE
44 01 438 Al, but differ significantly in their performance from the coating masses disclosed there.
Such essential further improvements in coating properties in the favor of mechanical values and possibly with certain losses in flow or weather resistance can be desirable and advantageous in practice for different reasons. One need only consider that in the course of industrial production of coating powder raw materials (tolerances in acid number and hydroxyl number of the polyester resins, in the hydroxyl equivalent weight or epoxy equivalent weight of the (3-hydroxyalkylamides and polyepoxides, as well as their particle size distribution), and their industrial processing to coating powders (dispersing quality), their application (layer thickness) and finally deformation of the parts coated with them (possibly insufficient tempering of the parts being deformed) partial deviations fron: the ideal parameters must be reckoned with.
EP 0 548 896 Al can be mentioned as rnerely an example, where it is stated how helpful an optimal particle size and shape of the binder is for the coating powders in order to conduct the best possible dispersal process of the coating powder raw material charge in the extruder, which has a significant effect on the quality of'the finished coating powder.
(Coating layers, which have pinholes as a result of deficiencies in dispersal, owing to nonideal particle size or other reasons, also exhibit reduced suitability for use in addition to a deterioration in surface appearance, for example, lower elasticity and reduced weather resistance.
The invention also concerns a carboxyl-functional polyester resin that has an acid number from 15 to 70 mg KOH/g polyester resin and a hydroxyl number from 10 or less mg KOH/g polyester resin and is composed of difunctional monomers, namely dicarboxylic acids and diols as well as optionally hydroxycarboxylic acids, said polyester resin being characterized by the fact that it contains a maximum of 80 mol % isophthalic acid, referred to the total amount of dicarboxylic acids, at least 20 mol% of at least another dicarboxylic acid from the group of aromatic dicarboxylic acids with 8 to 16 carbon atoms and/or aliphatic dicarboxylic acids with 4 to 22 carbon atoms and/or cycloaliphatic clicarboxylic acids with 8 to 16 carbon atoms and/or dimerized fatty acids in reference to the total amount of dicarboxylic acids, with the stipulation of a glass transition point of at least 35 C, at least 50 mol% of at least one branched aliphatic diol with 4 to 12 carbon atoms, which can also contain an ester group, a maxirnum of 50 mol% of at least one linear aliphatic diol with 2 to 22 carbon atoms and/or at least one cycloaliphatic diol with 6 to 16 carbon atoms with the stipulation of a glass transition point of at least 35 C, in which the mentioned diols include 1,5-pentanediol and/or at least one 1,5-pentanediol provided with one or more side alkyl substituents, like 3-methyl-1,5-pentanediol in a total molar amount from 0.5 to 30%, referred to the amount of all diols.
1,5-pentanediol is preferably used. A dimerized fatty alcohol can also be contained as diol.
The glass transition point is preferably at least 40 C and especially at least 45 C.
The coemployment of hydroxycarboxylic acids or their functional derivatives, like their inner esters (lactones) is naturally also possible. Likewise, instead of carboxylic acids, their functional derivatives, like esters or optionally anhydrides can be used.
Polyhydric alcohols that contain vicinal hydroxyl groups are substitutable by corresponding epoxide compounds.
The (3-hydroxyalkylamides mentioned under b) as curing agents are those that contain at least two hydroxyalkylamide groups per molecule. Particularly suitable according to the invention are (bis[N,N'-di((3-hydroxyetlryl)]adipamide) and (bis[N,N'-di((3-hydroxypropyl)]-adipamide), which are available under t:he names Primid XL-552 and Primid QM-1260. To achieve good coating properties 0.5 to 1.5, preferably 0.75 to 1.25, [3-hydroxyalkylamide groups are used for each carboxyl group of the carboxylated polyester. (3-Hydroxyalkylamide group-containing polyesters are also suitable. Stoichiometrically equivalent amounts of the binder partners are used in the examples presented below.
Polyepoxides are also suitable as curing agent component b). The curing agent is then a monomeric or polymeric polyepoxide with at least two epoxide groups. It can be a glycidyl ester of a monomeric polycarboxylic acid, which can be in particular terephthalic acid and/or trimellitic acid, preferably their combination and especially their combination in a ratio of about 3:1. Such a combination is the commercially available curing agent Araldit PT
910.
The curing agent can also be a glycidyl ether of cyanuric acid or isocyanuric acid in which this triglycidyl isocyanurate (TGIC) is the commercially available Araldit PT
810 and/or tris-((3-methylglycidyl) isocyanurate. The ciuring agent, however, can also be a glycidyl ester of a carboxyl-functional polyester resin and/or a glycidyl-functional polyacrylate.
The polyepoxide compounds disclosed in EP 0 600 546 Al also exhibit particular suitability, like epoxidized oils, epoxidized modified oils and epoxidized alkyds. To achieve good coating properties, 0.5 to 2.0, pref,-rably 0.75 to 1.5, epoxide groups are used for each carboxyl group of the carboxylated polyester.
In contrast to the situation in (3-hydroxylalkylamides, in addition to the desired polyester-epoxide reaction, a certain fraction of in.trinsic polymerization of the epoxide curing agent also occurs so that empirically determined biinder ratios are used in practice instead of the strictly stoichiometric amount ratios.
The coatings according to the invention can contain, as mentioned under c), ordinary inorganic or organic pigments, fillers, waxes, and wax derivatives, micronized plastics, like polyamides, polyethylene, polypropylene or polytetrafluoroethylene, as well as ordinary additives for production of coating powders, for example, flow control agents, degassing auxiliaries, oxidation stabilizers, light protection agents in the form of UV absorbers and/or HALS
compounds, accelerators, silica and/or aluminum oxide to improve flowability or tribo additives.
Production of the carboxyl-funcilional polyester resins according to the invention occurs in known fashion, according to which in a first reaction stage with diol excess and heating of the corresponding raw materials in the presence of ordinary esterification catalysts to temperatures of about 250 C and separation of the forming reaction water, a hydroxyl-functional polyester is produced which is converted in a secon(i reaction stage with one or more dibasic carboxylic acids, in which their functional derivatives can also be involved, to a carboxyl-functional polyester.
The method for thermosetting coating powder formulations based on carboxyl-functional polyester resins consists according to the invention of the fact that at least one representative of the group of (3-hydroxyalkylamides or polyepoxides and optionally additional additives according to one or more of the preceding claims are mixed with the binder resin, extruded at 80 to 130 C, withdrawn, granulated, ground and screened to a particle size of <100 m.
The invention also concerns the use of the aforementioned coating powder masses to produce protective layers of coatings on. objects by electrostatic coating or fluidized-bed coating.
The protective layers or coatings according to the invention are heated on the objects at temperatures between 120 and 220 C, preferably 130 to 200 C, especially 140 to 160 C. In this manner coating of a) heat-sensitive substrates, like plastics, wood or products derived from wood, high-strength (light) metal alloys, b) porous substrates that have a tendency toward degassing, like (hot-dip) galvanized metal parts, parts made of metal castings, ceramics or also c) thick-walled objects of high heat capacity is made possible in a technically and/or economically satisfactory manner.
The invention also concerns objects coated with the aforementioned coating powder masses.
In principle, other methods for producing coating masses from their components can also be used; perhaps they can be produced as homogeneous mixtures by means of solvents, from which the powdered masses can be recovered by precipitation or distillative separation of the solvent (spray drying). A special form of this process in which supercritical carbon dioxide takes the part of the solvent is known from V6'O 94/09913 (PCT/US93/10289).
Application of the coating masses according to the invention occurs according to methods common for coating powders. These include electrostatic spray devices which operate according to the corona or tribo process, and fluidized bed application is also common.
The coating powders according t:o the invention have an adequate storage stability and produce, after crosslinking at temperatures from 120 to 220 C, a very good flow; a good resistance to (rapid) weathering and their high mechanical level, which withstands aging very well, has already been emphasized.
The production and properties of the polyester resins according to the invention and those also used for comparison and the coating powders produced from them are described by means of the following examples, which do not restrict the scope of the invention.
For characterization of the final properties of the polyester resin, their acid number (AN), hydroxyl number (HN), and their glass transition point (Tg) are used.
Production of carboxyl-functional polyester resins:
Comparative Example A
440.08 g(4.225 mol) 2,2-dimethyl-1,3-propanediol and 69.22 g(1.115 mol) ethylene glycol are introduced into a 2-L reactiori vessel equipped with a stirrer, temperature sensor, partial reflux column, distillation bridge, and inert gas feed (nitrogen), then melted during heating to a maximum of 140 C under a nitrogen atmosphere. During agitation, 801.63 g (4.825 mol) terephthalic acid and 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst are then added and the temperature is raised in steps to 240 C. The reaction is continued at this temperature until a distillate no longer forms and the acid number of the hydroxy-functional polyester resin is <10 mg KOH/g of polyester resin.
47.35 g isophthalic acid, 41.65 g adipic acid, and 49.08 g cyclohexane-1,4-dicarboxylic acid (0.285 mol each) are then added and esterification continued until the desired acid number is reached (about 34), the reaction being supported by the use of vacuum, about 100 mbar, the finished resin has the following characteristics: AN 33.4, HN 3.4, Tg about 55.5 C.
Comparative Example B
In similar fashion to Comparative Example A, 433.31 g (4.16 mol) 2,2-dimethyl-1,3--propanediol, 73.25 g(1.18 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 802.46 g (4.83 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted in the described manner with the addition of 70.61 g isophthalic acid and 62.11 g of adipic acid (0.425 mol each) to the finished polyester resin.
The finished resin has the following characteristics: AN 34.6, HN 2.4, Tg about 53.5 C.
Comparative Example C
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 38.49 g(0.62 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.7, HN 2.8, Tg about 58.0 C.
Comparative Example D
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethylene glycol, 36.64 g (0.31 mol) 1,6-hexanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.0, HN 4.5, Tg about 56.0 C.
Comparative Example E
In similar fashion to Comparative Example A, 445.28 g (4.275 mol) 2,2-dimethyl-1,3--propanediol, 70.15 g(1.13 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 794.98 g (4.785 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 47.35 g isophthalic acid, 41.65 g adipic acid, and 49.08 g cyclohexane-1,4-dicarboxylic acid (0.285 mol each). The finished resin has the following characteristics: AN
27.5, HN 3.7, Tg about 56.0 C.
Comparative Example F
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 38.49 g(0.62 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 777.54 g (4.68 mol) terephthalic acid are converted to a hydroxy-functional polyester resin in a first reaction stage.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 58.46 g adipic acid (0.40 mol). The finished resin has the following characteristics: AN 34.6, HN 4.5, Tg about 55.5 C.
Comparative Example G
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 36.94 g (0.595 mol) ethylene glycol, 2.95 g (0.025 mol) 1,6-hexanediol, 0.1%, in reference to the total amount of finished. resin, of an Sn-containing catalyst and 777.54 g (4.68 mol) terephthalic acid are converted to a hydroxy-functional polyester resin in a first reaction stage.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 58.46 g adipic acid (0.40 mol). The finished resin has the following characteristics: AN 34.4, HN 3.1, Tg about 55.0 C.
Example 1 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethylene glycol, 32.29 g (0.31 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finishedl resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.2, HN 3.8, Tg about 56.0 C.
Example 2 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethylene glycol, 36.64 g (0.31 mol) 3-methyl-1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.0, HN 3.8, Tg about 55.5 C.
Example 3 In similar fashion to Comparative Example A, 472.89 g (4.54 mol) 2,2-dimethyl-1,3--propanediol, 24.83 g (0.40 mol) ethylene glycol, 41.66 g (0.40 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished. resin, of an Sn-containing catalyst, and 792.49 g (4.77 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 56.49 g (0.34 mol) isophthalic acid, 68.88 g (0.40 mol) cyclohexane-1,4-dicarboxylic acid and 24.84 g adipic acid (0.17 mol). The finished resin has the following characteristics: AN 34.3, HN 4.1, Tg about 55.0 C.
Example 4 In similar fashion to Comparative Example A, 472.89 g (4.54 mol) 2,2-dimethyl-1,3--propanediol, 24.83 g (0.40 mol) ethylene glycol, 20.83 g (0.20 mol) 1,5-pentanediol, 23.64 g (0.20 mol) 3-methyl-1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 792.49 g (4.77 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 56.49 g (0.34 mol) isophthalic acid, 68.88 g (0.40 mol) cyclohexane-1,4-dicarboxylic acid, and 24.84 g(0.17 mol) adipic acid. The finiished resin has the following characteristics: AN 34.3, HN 4.1, Tg about 55.0 C.
Example 5 In similar fashion to Comparative Example A, 475.49 g (4.565 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethyleine glycol, 25.00 g (0.24 mol) 1,5-pentanediol, 18.91 g (0.16 mol) 3-methyl-1,5-pentanediol, 5.90 g (0.044 mol) trimethylolpropane, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g (0.77 mol) isophthalic acid, and 29.23 g (0.20 mol) adipic acid.
The finished resin has the following characteristics: AN 34.3, HN 3.8, Tg about 54.0 C.
Example 6 In similar fashion to Comparative Example A, 444.76 g (4.27 mol) 2,2-dimethyl-1,3--propanediol, 38.49 g (0.62 mol) ethylene glycol, 46.87 g (0.45 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 810.76 g (4.88 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 137.76 g (0.80 mol) cyclohexane-1,4-dicarboxylic acid. The finished resin has the following characteristics: AN 33.5, HN 3.0, Tg about 52.5 C.
Example 9 In similar fashion to Comparative Example A, 469.24 g (4.505 mol) 2,2-dimethyl-1,3--propanediol, 27.94 g (0.45 mol) ethylene glycol, 46.87 g (0.45 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished. resin, of an Sn-containing catalyst, and 808.27 g (4.865 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 103.84 g isophthalic acid (0.625 mol) and 14.61 g adipic acid (0.10 mol).
The finished resin has the following characteristics: AN 27.3, HN 3.9, Tg about 57.5 C.
Example 10 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 36.94 g (0.595 mol) ethylene glycol, 2.61 g (0.025 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finishedi resin, of an Sn-containing catalyst, and 777.54 g (4.68 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 58.46 g adipic acid (0.40 mol). The finished resin has the following characteristics: AN 34.6, HN 3.8, Tg about 55.2 C.
Example 11 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 33.83 g (0.545 mol) ethylene glycol, 7.81 g (0.075 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 794.15 g (4.78 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 43.84 g adipic acid (0.30 mol). The finished resin has the following characteristics: AN 34.2, HN 4.2, Tg about 55.0 C.
Example 12 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 28.87 g(0.465 mol) ethylene glycol, 16.14 g(0.155 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of fmished resin, of an Sn-containing catalyst, and 794.15 g (4.78 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g (0.60 mol) isophthalic acid and 43.84 g (0.30 mol) adipic acid. The fuushed resin has the following characteristics: AN 33.8, HN 3.0, Tg about 54 C.
Production of coating powders All coating powders listed in the tables can be produced according to the following formulations:
a) Coating powders crosslinked with P-hydroxyalkylamide:
Raw material Parts by weiQht Polyester resin 61.86 Primid XL-552 3.26 Bylr364 P (Byk Chemie) 1.30 Benzoin 0.20 Titan 23 10 (Kronos) 31.48 b) Coating powders crosslinked with polyepoxide:
Parts by weight Parts by weight Comparative Examples A, B, C Comparative Example E
Raw material Examples 1-4, 6 Example 9 Polyester resin 59.48 58.18 TM
Araldit PT 810 4.48 -TM
Araldit PT 910 - 4.68 DT 3126 (CIBA) 1.16 2.26 BykM364 P (Byk Chemie) 1.30 1.30 Benzoin 0.20 0.20 Titaii 2310 (Kronos) 31.48 31.48 The formulation components are mixed dry in a Henschel mixer at 700 rpm for 30 seconds and then extruded on a Buss Co. kneader (PLK 46) at a surface temperature of 100 C.
The obtained extrudate is cooled, crushed, ground and screened to a particle fineness of <90 m.
The coating tests occur on yellow chrome-plated aluminum sheets Al Mg 1 F 13, mill finish, thickness 0.7 mm at a stoving ternperature of 180 C and stoving time of 10 minutes (object temperature). The coating film thickness is about 80 m.
To simulate aging the coated sheets are exposed for a period of 4 weeks to an alternating climate: 4 days each at room climate (23 2 C, about 50% relative humidity) and 3 days at 55 C
in a heating cabinet. This cycle is repeated, the coated test sheets being subjected at weekly intervals at room temperature to the ball impact test according to ASTM D
2794, ball diameter '/z" at a maximum of 70 inch pound (maximum possible deformation of the sheet which still does not lead to cracking) in order to evaluatc, the flexibility of the coatings.
After performing the last such test series, the test sheets are stored for 24 hours in a refrigerator and then investigated for impact strength again at 8 C.
To test the weather resistance, the test sheets are weathered in the Q-panel accelerated weathering tester according to ASTM G 53-77 using UVB-313 lamps from the apparatus manufacturer (The Q-Panel Company) for 168 hours (formulations that contain (3-hydroxyalkyl-amide) for 336 hours (formulations containing polyepoxide). The conditions are as follows:
4 h UV at 60 C and 4 h condensation at 45 C with continuous alternation. To evaluate the weathering resistance of the test specimen, their initial and final luster according to Gardner are compared, measured under 60 .
The following tables show the obtained results a) for coating powders crosslinked with (3-hydroxyalkylamide and b) for coating powders crosslinked with polyepoxides:
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Since the 1970s, coating powders based on a carboxyl-functional polyester resin and the polyfunctional epoxy compound triglyci'ldyl isocyanurate (TGIC) have been considered the industry standard for production of weatherproof coatings in fagade construction, in automobile accessories, and general industrial applications. For example, DE 26 18 729 describes polyester resins with acid numbers from 50 to 100 mg KOH/g of polyester for such formulations.
An important reason for the technical supremacy of any coating powder system lies in the chemical nature of the crosslinking reaction. Since an addition reaction between the oxirane and carboxyl groups of the binder partners is involved, no cleavage products are liberated, which is advantageous for the optical appearance of the stoved coatings with higher layer thickness, but also for the environment.
Beginning a few years ago, the toxicological risk of coating powders containing TGIC
was increasingly discussed, was and is an incentive to search for epoxy-functional but also other alternative products. Although TGIC and TGIC-containing coating powder has had to be marked accordingly since then in many countries of Europe and elsewhere because of the mutagenic potential of this curing agent, it is still tiue that a substitute for TGIC
that is technically equivalent in all respects is presently not available.
Among other things, (3-hydroxyalkylamides, like Primid XL-552 (bis[N,N'-di((3--hydroxyethyl)]adipamide) or Primid QM-1260 (bis[N,N'-di((3-hydroxypropyl)]adipamide), both from EMS Chemie, are now offered as alternatives to TGIC as a curing agent for carboxyl-functional polyester resins. A special feature of these curing agents lies in their complete toxicological acceptability according to the present state of knowledge. EP 0 discloses (3-hydroxyalkylamide-group-containing polyesters that represent polymers of similar functionality and applicability.
21757-'81 Additional posslble. alternatives to TGIC as curing agents for carboxyl-functional polyester resins include thtt glycidyl esters of aromatic or cycioaliphatic dicar"boxyiic acids, see EP 0 110 ^-, 50 E l; a corresponding commercially available curing agent of similar chemical structure is Araidit~a~ PT 910 (terephthalic acid dialycidyl ester/trimellitic acid triglycidyl ester, about 75:25) from CBA Spezialitatenchemie GmbH. The presence of the trifunctional trimellitic acid ester in Araldit~~% PT 910 is dtemed advantageous for the crosslinking density of the stoved :,oatings in comparison with pure diglycidyl esters. Another possibility is offered by trie use of po,.idized oils, see EP 0 600 546 Al; binder systems of this type are offered by DS1A
Resins under the name Uranox . Another potential alternative is a polyepoxide very similar to TGIC, tris-((3-methylglycidyl) isocyanurate, see WO 96/17026. Polymer epoxides are also known as epoxide curing agents.
All the mentioned products are now gaining increasing significance in the formulation of coating powders from carboxyl-functional polyester resins, but in which TGIC
can still claim numerous markets.
Polyester resins for production of weather-stable coating powders, which are cured with polyepoxide and/or P-hydroxyalkylamide, have an acid number in the range from 15 to 70 mg KOrUg of polyester and a hydroxyl number less than or equal to 10 mg KOH/g of polyester and essentially consist of units of aromatic dicarboxylic acids, like terephthalic and isophthalic acids, in addition to which limited amounts of aliphatic and/or cycloaliphatic dicarboxylic acids also find application, like adipic and/or cyclohexanedicarboxylic acid, and aliphatic diols and preferably branched ones, like neopentyl glycol, in addition to limited fractions of linear and/or cycloaliphatic diols. The coemployment of hydroxycarboxylic acids that are functional derivatives, like their inner esters (lactones), is also possible.
Modification of such resins by using dimeric and trimeric fatty acids is also lmown. Limited amounts of trifunctional or higher functional and optionally monofunctional compounds can also be used.
It is now being observed that a generally more or less strongly pronounced phenomenon in coating powders, namely that of physical aging, also occurs, generally strongly, in those that are formulated from carboxyl-functional polyester resins and polyepoxides, and even more strongly in those formulated from carboxyl-functional polyester resins and (3-hydroxylalkylamides. Physical aging is expressed, among other things, in a distinct reduction of flexibility of the stoved coatings over days and weeks and, depending on the employed system, even when the coated and stoved parts are stored under normal climatic conditions (23 C, 50% relative humidity), as presented in detail and clearly in DE 44 01 438 Al.
The above application discloses that coating powders whose binder consists of a) more closely defined linear carboxyl-functional polyester resins and b) P-hydroxyalk-ylamide andJor polyfunctional epoxy compounds experience no recordable degradation of flexibility as a result of physical aging if the percentage of isophthalic acid in the polyester resins in reference to the total amount of employed dicarboxylic acids does not exceed 10 mol%. By means of such formulations, the high mechanical requirements that are imposed, for example, in precoating metal and coil coating technology as a result of later deformation of the coated parts can be satisfied in coating powders.
However, it has been shown that the coatings with respect to their resistance to rapid weathering in the Q-panel accelerated weathering test according to ASTM G 53-77 do not reach the level that is now generally required in coating powders for fagade applications according to the examples disclosed in DE 44 01 438 Al.
DE 40 12 020 Al discloses a method for coating of substrates with thermosetting coating powder preparations at high temperature and short times. Such coating powder and preparations consist of A) carboxyl-functional polyester resin, B) a compound capable of reaction with the carboxyl groups and C) ordinary additives.
The polyester resins A) that cont:ain hydroxyl groups can include two or more carboxyl groups per molecule and have an acid number from 10 to 70 and a hydroxyl number from 0 to 40 with the stipulation that the hydroxyl number is always lower than the acid number.
Oxirane compounds with two or more epoxide groups per molecule, in which triglycidyl isocyanurate, bisphenol glycidyl ether and/or its higher homologs are included, are disclosed as curing agent B).
Specifically, however, coemployment of compounds with the functionality greater than 2, stating a minimum fraction of 1 mol%, referred to the total formulation of the employed components A) and B) is referred to in particular. Thus, the use of significant amounts of trifunctional components trimethylpropane [sic] and trimellitic acid anhydride is disclosed in all the examples.
US 5 262 510 A discloses thermosetting coating powder masses that are obtained by a combination of a polyester resin with at least four reactive carboxyl groups per molecule with an epoxy resin based on bisphenol A diglycidyl ether.
Aliphatic or alicyclic alcohols with 2 to 3 reactive groups and 2 to 6 carbon atoms and aliphatic, alicyclic or aromatic carboxyli'lc acids with 2 to 4 carboxyl groups and 4 to 12 carbon atoms are then mentioned as monomers to produce the polyester resin. 1,5-Pentanediol without further specification of its purpose is also mentioned in the overall disclosure of US 5 262 510 A
among the alcohols with two reactive groups.
DE 43 35 845 discloses that coat:ing powder masses made from polyester resins with an acid number from 15 to 75 mg KOH/g polyester, in which isophthalic acid makes up at least 80 mol% of the total amount of all the employed dicarboxylic acids, and at least (3-hydroxy-alkylamide as curing agent exhibit extraordinarily high resistance in the rapid weathering test with UVB exposure.
EP 0 389 926 B1 discloses that coating powder masses made from polyester resins with an acid number from 15 to 70 mg KOH/g of polyester with at least 75 mol%
isophthalic acid, in reference to the total amount of all employed dicarboxylic acid, and triglycidyl isocyanurate as curing agent, have extraordinarily high resistance in the rapid weathering test with UVB
exposure.
However, it is known, on the other hand, that a weak point in coating powder masses with high percentages of isophthalic acids is precisely the flexibility and it is quite impossible in numerous color shades to appropriately deform the coated objects (even right after stoving) without damaging these paint layers (at least on their surface).
EP 0 389 926 B1 proposes the coemployment of resin raw materials with a functionality greater than 2 in a total molar amount of a maximum of 8% in coating powder masses based on carboxyl-functional polyester resin with, at least 75 mol% isophthalic acid as acid component and triglycidyl isocyanurate, which simultaneously have as objective the highest weather resistance with the best possible flexibility. Moreover, this patent offers hints that the use of isophthalic acid in comparison with terephthalic acid (in general) results in inadequate impact strength. The same is also true for the powdered coating masses disclosed in DE 43 35 845 C2 in which (3-hydroxyalkylamides are contained as curing agents.
A high percentage of terephthalic acid as the aromatic dicarboxylic acid is deemed essential to achieve high mechanical properties for carboxylated polyester resin in GB 2 189 489 A.
The formulation disclosed in the Comparative Example of DE 44 01 438 Al does provide the resistance to rapid weathering requil-ed in European fagade construction, but not the required resistance to physical aging according to the values presented in the tables of this unexamined patent application with their detrimental consequences for deformability of the coating.
The manufacturers of fagade elements who operate according to the rational precoating metal or coil coating technology therefore do not have coating powder masses from carboxyl-functional polyester resins and polyepoxides (because of the cleavage product-free nature of their crosslinking reaction) or coating powder masses from carboxyl-functional polyester resins and (3-hydroxyalkylamides (because of their full toxicological acceptability according to the present state of knowledge), which impart the weather resistance to the fagade parts being subsequently deformed that is considered the standard nowadays for fagade construction.
With respect to the high degree of environmental compatibility, which characterizes coating powders over other coatings, this is an unsatisfactory circunlstance, since the solvent-containing coatings available as alternatives require removal of the emissions for ecological reasons by costly afterburning and/or filter systems from the exhaust of the operations that process such coatings systems, which creates costs and burdens the environment.
According to the invention there is provided a coating powder formulation consisting of at least one a) carboxyl-functional polyester resin, at least b) crosslinking agents chosen from the group of organic compounds that are capable of reaction with the carboxyl groups of the polyester to produce a covalent bond, and c) ordinary additives as well as optional pigments and fillers in which the a) polyester resin has an acid number from 15 to 70 mg KOH/g of polyester resin and a hydroxyl number of 10 or less mg KOH1g polyester resin and consists of dicarboxylic acids, diols and optionally hydroxycarboxylic acids, said coating powder formulation being characterized by the fact that the polyester resin contains a maximum of 80 mol% isophthalic acid, referred to the total amount of dicarboxylic acid, at least 20 mol% of at least one other dicarboxylic acid of the group of aromatic dicarboxylic acids with 8 to 16 carbon atoms and/or aliphatic dicarboxylic acids with 4 to .22 carbon atoms and/or cycloaliphatic dicarboxylic acids with 8 to 16 carbon atoms and/or dimerized fatty acids, in reference to the total amount of dicarboxylic acids, with the stipulation of a glass transition point of at least 35 C, at least 50 mol% of at least one branched aliphatic diol with 4 to 12 carbon atoms, which can also contain an ester group, a maximum of 50 mol% of at least one linear aliphatic diol with 2 to 22 carbon atoms and/or at least one cycloaliphatic diol with 6 to 16 carbon atoms, in reference to the total amount of diols, with stipulation of a glass transition point of at least 35 C, in which the mentioned diols include 1,5-pentanediol and/or at least one 1,5-pentanediol provided with one or more side alkyl substituents, like 3-methyl-1,5-pentanediol in a total molar amount from 0.5 to 30%, referred to the amount of all diols.
A dimerized fatty alcohol is optionally additionally contained as a diol.
1,5-Pentanediol.is preferably used.
5a In one aspect, the invention provides a coating powder formulation, comprising: (a) at least one carboxyl-functional polyester resin with an acid number of from 15 to 70 mg KOH/g of the polyester resin, a hydroxyl number of 10 or less mg KOH/g of the polyester resin and a glass transition temperature of at least 35 C, wherein: (i) the polyester resin composed of difunctional monomers comprises at least one dicarboxylic acid and at least one diol monomer, (ii) the polyester resin contains a maximum of 80 mol% of isophthalic acid relative to the total amount of all dicarboxylic acids, (iii) the polyester resin contains at least 20 mol% of at least one dicarboxylic acid selected from the group consisting of an aromatic dicarboxylic acid with 8 to 16 carbon atoms, an aliphatic dicarboxylic acid with 4 to 22 carbon atoms, a cycloaliphatic dicarboxylic acid with 8 to 16 carbon atoms, a dimerized fatty acid and a mixture thereof, relative to the total amount of all dicarboxylic acids, (iv) the polyester resin contains at least 50 mol% of at least one branched aliphatic diol with 4 to 12 carbon atoms, a maximum of 50 mol% of at least one diol selected from the group consisting of a linear aliphatic diol with 2 to 22 carbon atoms, a cycloaliphatic diol with 6 to 16 carbon atoms and a mixture thereof, relative to the total amount of all diols, and (v) the polyester resin contains among the diols 1,5-pentanediol or 1,5-pentanediol with one or more side alkyl substituents at a total molar concentration of from 0.5 to 30% relative to the amount of all diols present; and (b) at least one organic compound curing agent which reacts with the carboxyl groups of the polyester resin to produce covalent bonds.
The glass transition point is preferably at least 40 C and especially at least 45 C.
= 21757-181 5b The coemployment of hydroxycarboxylic acid or their functional derivatives is naturally also possible, like their inner esters (lactones). Likewise, instead of carboxylic acids, their functional derivatives, like esters or optionally anhydrides, can be used. Polyhydric alcohols containing vicinal hydroxyl groups can be substituted by corresponding epoxide compounds.
,6-Hydroxyalkylamide or polyepoxides are used as curing agents.
Preferably 5 to 30 mol% isophthalic acid is used.
The surprising thing of the present invention is the entirely unexpected effect according to which, by coemployment of a,w-diols that have five carbon atoms in sequence between hydroxyl groups, the coating powders with more than 10 mol% isophthalic acid in reference to the total amount of dicarboxylic acids used duririg formulation of the polyester not only exhibit the resistance to the physical aging that is inherent to the coating masses according to the prior art disclosed by DE 44 01 438 Al, whose polyester component has an isophthalic acid percentage of at most 10 mol% in reference to the total employed dicarboxylic acid, but, in addition, they have a significantly improved resistance to rapid aging of the Q-panel accelerated weathering test according to ASTM G 53-77.
It must be deemed quite particularly surprising that this unexpected effect occurs clearly as a result of coemployment of a,co-diol.s that have five carbon atoms in sequence between the hydroxyl groups even at a percentage of 0.5 mol%, in reference to the total amount of the employed diol, as demonstrated by the corresponding examples and Comparative Examples.
Previous experiments were unsuccessful to stabilize against physical aging coating powders from (3-hydroxyalkylamides, like Primid XL-552 and carboxyl-functional polyester resins that have an isophthalic acid percentage of more than 10 mol% in reference to the total amount of employed carboxylic acids, by coemployment of resin raw materials whose flexibilizing action on the coating powders has been repeatedly demonstrated (see for example, the practical example in DE 43 35 845 C2, which discloses 1,4-cyclohexanedicarboxylic acid, adipic acid or 1,6-hexanediol alone or in combination) or in DE 44 01 438 Al (here adipic acid and/or 1,4-cyclohexanedicarboxylic aciii are disclosed), as demonstrated by Comparative Examples C and D.
Previous experiments failed to stabilize, against physical aging, coating powders made from a polyepoxide, like triglycidyl isocyanurate and carboxyl-functional polyester resins that contain an isophthalic fraction of more than 10 mol%, in reference to the total amount of employed dicarboxylic acid by coemployment of resin raw materials with flexibilizing action on the coating powders, as suggested, for example, according to EP 0 110 450 B1 by means of adipic acid and 1,6-hexanediol in combination or according to DE 44 01 438 Al by adipic acid and/or 1,4-cyclohexanedicarboxylic acid.
DE 44 01 438 Al does disclose the use of at least 50 mol fractions (in reference to the total amount of employed diols) and at llast one branched aliphatic diol with 4 to 12 carbon atoms, which can also be understood to include 3-methyl-l,5-pentanediol, as well as the possible coemployment of at least one linear aliphatic diol with 2 to 22 carbon atoms, which also includes 1,5-pentanediol. However, there are no indications of the special suitability of these raw materials for achieving increased resistance against physical aging (despite a higher percentage of isophthalic acid) in addition to improved resistance to rapid weathering based on increased fractions of isophthalic acid.
Very good results are obtained from the coemployment of 5.8 mol% 1,5-pentanediol in reference to the total amount of all employed diols, in a polyester that contains, among other things, 13.6 mol% isophthalic acid in reference to the total amount of employed dicarboxylic acid and is formulated with triglydicyl isocyanurate or Primid XL-552 to a coating powder. In addition to the corresponding resistance to loss of flexibility as a result of physical aging, coating powder masses of this composition after stoving provided very good resistance to rapid weathering during UVB exposure. The excellent flow and luster of the coatings also merit special emphasis. Excellent results are also obtained if 3-methyl-1,5-pentanediol is used instead of 1,5-pentanediol. It is particularly surprising that, when 1,6-hexanediol was used instead of 3-methyl-1,5-pentanediol (despite the same molecular weight of two raw materials), the formulation with 1,6-hexanediol exhibits drawbacks with respect to flexibility after storage, although a higher contribution to flexibilization of the coating could be expected from an unbranched chain of six carbon atoms than from a chain of five carbon atoms with a side methyl group. Considerations of this type are also set forth in the brochure IP-70 of Amoco Chemical Corporation (How Ingredients I.nfluence; Unsaturated Polyester Properties), page 20, first section, second paragraph.
Naturally, it is possible within the context of the present invention, by expedients used according to the prior art, to improve the mechanical properties of coating powder films with respect to flexibility and/or weather resistance stabilized against physical aging by the coemployment, according to the invention, of (substituted) 1,5-pentanediol(s) and/or substituted 3-oxa- 1,5-pentanediol(s).
Very good flow in addition to higher resistance to physical aging and very good weather resistance were found in our own expen.ments in a formulation that contains, in addition to 13.6 mol% isophthalic acid, in reference; to the total amount of employed dicarboxylic acids, 4.5 mol% 1,5-pentanediol and 3 mol% :3-methyl-1,5-pentanediol, in reference to the total employed diols, and also 0.4 mol% trimethylolpropane, in reference to the total amount of all employed raw materials.
Formulations produced according to the invention (using 1,5-pentanediol and/or 3-methyl-1,5-pentanediol) with a molar fraction of terephthalic acid >85% as well as an isophthalic fraction <10%, in reference to the total amount of all employed dicarboxylic acids, were, in comparison with the two examples mentioned from DE 44 01 438 Al, still very readily deformable in the reserve impact test in the cooled state, whereas they were not inferior to these compounds in the Q-panel accelerated vveathering test according to ASTM G 53-77. The resins so formulated therefore do lie formally within the scope of disclosure of DE
44 01 438 Al, but differ significantly in their performance from the coating masses disclosed there.
Such essential further improvements in coating properties in the favor of mechanical values and possibly with certain losses in flow or weather resistance can be desirable and advantageous in practice for different reasons. One need only consider that in the course of industrial production of coating powder raw materials (tolerances in acid number and hydroxyl number of the polyester resins, in the hydroxyl equivalent weight or epoxy equivalent weight of the (3-hydroxyalkylamides and polyepoxides, as well as their particle size distribution), and their industrial processing to coating powders (dispersing quality), their application (layer thickness) and finally deformation of the parts coated with them (possibly insufficient tempering of the parts being deformed) partial deviations fron: the ideal parameters must be reckoned with.
EP 0 548 896 Al can be mentioned as rnerely an example, where it is stated how helpful an optimal particle size and shape of the binder is for the coating powders in order to conduct the best possible dispersal process of the coating powder raw material charge in the extruder, which has a significant effect on the quality of'the finished coating powder.
(Coating layers, which have pinholes as a result of deficiencies in dispersal, owing to nonideal particle size or other reasons, also exhibit reduced suitability for use in addition to a deterioration in surface appearance, for example, lower elasticity and reduced weather resistance.
The invention also concerns a carboxyl-functional polyester resin that has an acid number from 15 to 70 mg KOH/g polyester resin and a hydroxyl number from 10 or less mg KOH/g polyester resin and is composed of difunctional monomers, namely dicarboxylic acids and diols as well as optionally hydroxycarboxylic acids, said polyester resin being characterized by the fact that it contains a maximum of 80 mol % isophthalic acid, referred to the total amount of dicarboxylic acids, at least 20 mol% of at least another dicarboxylic acid from the group of aromatic dicarboxylic acids with 8 to 16 carbon atoms and/or aliphatic dicarboxylic acids with 4 to 22 carbon atoms and/or cycloaliphatic clicarboxylic acids with 8 to 16 carbon atoms and/or dimerized fatty acids in reference to the total amount of dicarboxylic acids, with the stipulation of a glass transition point of at least 35 C, at least 50 mol% of at least one branched aliphatic diol with 4 to 12 carbon atoms, which can also contain an ester group, a maxirnum of 50 mol% of at least one linear aliphatic diol with 2 to 22 carbon atoms and/or at least one cycloaliphatic diol with 6 to 16 carbon atoms with the stipulation of a glass transition point of at least 35 C, in which the mentioned diols include 1,5-pentanediol and/or at least one 1,5-pentanediol provided with one or more side alkyl substituents, like 3-methyl-1,5-pentanediol in a total molar amount from 0.5 to 30%, referred to the amount of all diols.
1,5-pentanediol is preferably used. A dimerized fatty alcohol can also be contained as diol.
The glass transition point is preferably at least 40 C and especially at least 45 C.
The coemployment of hydroxycarboxylic acids or their functional derivatives, like their inner esters (lactones) is naturally also possible. Likewise, instead of carboxylic acids, their functional derivatives, like esters or optionally anhydrides can be used.
Polyhydric alcohols that contain vicinal hydroxyl groups are substitutable by corresponding epoxide compounds.
The (3-hydroxyalkylamides mentioned under b) as curing agents are those that contain at least two hydroxyalkylamide groups per molecule. Particularly suitable according to the invention are (bis[N,N'-di((3-hydroxyetlryl)]adipamide) and (bis[N,N'-di((3-hydroxypropyl)]-adipamide), which are available under t:he names Primid XL-552 and Primid QM-1260. To achieve good coating properties 0.5 to 1.5, preferably 0.75 to 1.25, [3-hydroxyalkylamide groups are used for each carboxyl group of the carboxylated polyester. (3-Hydroxyalkylamide group-containing polyesters are also suitable. Stoichiometrically equivalent amounts of the binder partners are used in the examples presented below.
Polyepoxides are also suitable as curing agent component b). The curing agent is then a monomeric or polymeric polyepoxide with at least two epoxide groups. It can be a glycidyl ester of a monomeric polycarboxylic acid, which can be in particular terephthalic acid and/or trimellitic acid, preferably their combination and especially their combination in a ratio of about 3:1. Such a combination is the commercially available curing agent Araldit PT
910.
The curing agent can also be a glycidyl ether of cyanuric acid or isocyanuric acid in which this triglycidyl isocyanurate (TGIC) is the commercially available Araldit PT
810 and/or tris-((3-methylglycidyl) isocyanurate. The ciuring agent, however, can also be a glycidyl ester of a carboxyl-functional polyester resin and/or a glycidyl-functional polyacrylate.
The polyepoxide compounds disclosed in EP 0 600 546 Al also exhibit particular suitability, like epoxidized oils, epoxidized modified oils and epoxidized alkyds. To achieve good coating properties, 0.5 to 2.0, pref,-rably 0.75 to 1.5, epoxide groups are used for each carboxyl group of the carboxylated polyester.
In contrast to the situation in (3-hydroxylalkylamides, in addition to the desired polyester-epoxide reaction, a certain fraction of in.trinsic polymerization of the epoxide curing agent also occurs so that empirically determined biinder ratios are used in practice instead of the strictly stoichiometric amount ratios.
The coatings according to the invention can contain, as mentioned under c), ordinary inorganic or organic pigments, fillers, waxes, and wax derivatives, micronized plastics, like polyamides, polyethylene, polypropylene or polytetrafluoroethylene, as well as ordinary additives for production of coating powders, for example, flow control agents, degassing auxiliaries, oxidation stabilizers, light protection agents in the form of UV absorbers and/or HALS
compounds, accelerators, silica and/or aluminum oxide to improve flowability or tribo additives.
Production of the carboxyl-funcilional polyester resins according to the invention occurs in known fashion, according to which in a first reaction stage with diol excess and heating of the corresponding raw materials in the presence of ordinary esterification catalysts to temperatures of about 250 C and separation of the forming reaction water, a hydroxyl-functional polyester is produced which is converted in a secon(i reaction stage with one or more dibasic carboxylic acids, in which their functional derivatives can also be involved, to a carboxyl-functional polyester.
The method for thermosetting coating powder formulations based on carboxyl-functional polyester resins consists according to the invention of the fact that at least one representative of the group of (3-hydroxyalkylamides or polyepoxides and optionally additional additives according to one or more of the preceding claims are mixed with the binder resin, extruded at 80 to 130 C, withdrawn, granulated, ground and screened to a particle size of <100 m.
The invention also concerns the use of the aforementioned coating powder masses to produce protective layers of coatings on. objects by electrostatic coating or fluidized-bed coating.
The protective layers or coatings according to the invention are heated on the objects at temperatures between 120 and 220 C, preferably 130 to 200 C, especially 140 to 160 C. In this manner coating of a) heat-sensitive substrates, like plastics, wood or products derived from wood, high-strength (light) metal alloys, b) porous substrates that have a tendency toward degassing, like (hot-dip) galvanized metal parts, parts made of metal castings, ceramics or also c) thick-walled objects of high heat capacity is made possible in a technically and/or economically satisfactory manner.
The invention also concerns objects coated with the aforementioned coating powder masses.
In principle, other methods for producing coating masses from their components can also be used; perhaps they can be produced as homogeneous mixtures by means of solvents, from which the powdered masses can be recovered by precipitation or distillative separation of the solvent (spray drying). A special form of this process in which supercritical carbon dioxide takes the part of the solvent is known from V6'O 94/09913 (PCT/US93/10289).
Application of the coating masses according to the invention occurs according to methods common for coating powders. These include electrostatic spray devices which operate according to the corona or tribo process, and fluidized bed application is also common.
The coating powders according t:o the invention have an adequate storage stability and produce, after crosslinking at temperatures from 120 to 220 C, a very good flow; a good resistance to (rapid) weathering and their high mechanical level, which withstands aging very well, has already been emphasized.
The production and properties of the polyester resins according to the invention and those also used for comparison and the coating powders produced from them are described by means of the following examples, which do not restrict the scope of the invention.
For characterization of the final properties of the polyester resin, their acid number (AN), hydroxyl number (HN), and their glass transition point (Tg) are used.
Production of carboxyl-functional polyester resins:
Comparative Example A
440.08 g(4.225 mol) 2,2-dimethyl-1,3-propanediol and 69.22 g(1.115 mol) ethylene glycol are introduced into a 2-L reactiori vessel equipped with a stirrer, temperature sensor, partial reflux column, distillation bridge, and inert gas feed (nitrogen), then melted during heating to a maximum of 140 C under a nitrogen atmosphere. During agitation, 801.63 g (4.825 mol) terephthalic acid and 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst are then added and the temperature is raised in steps to 240 C. The reaction is continued at this temperature until a distillate no longer forms and the acid number of the hydroxy-functional polyester resin is <10 mg KOH/g of polyester resin.
47.35 g isophthalic acid, 41.65 g adipic acid, and 49.08 g cyclohexane-1,4-dicarboxylic acid (0.285 mol each) are then added and esterification continued until the desired acid number is reached (about 34), the reaction being supported by the use of vacuum, about 100 mbar, the finished resin has the following characteristics: AN 33.4, HN 3.4, Tg about 55.5 C.
Comparative Example B
In similar fashion to Comparative Example A, 433.31 g (4.16 mol) 2,2-dimethyl-1,3--propanediol, 73.25 g(1.18 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 802.46 g (4.83 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted in the described manner with the addition of 70.61 g isophthalic acid and 62.11 g of adipic acid (0.425 mol each) to the finished polyester resin.
The finished resin has the following characteristics: AN 34.6, HN 2.4, Tg about 53.5 C.
Comparative Example C
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 38.49 g(0.62 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.7, HN 2.8, Tg about 58.0 C.
Comparative Example D
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethylene glycol, 36.64 g (0.31 mol) 1,6-hexanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.0, HN 4.5, Tg about 56.0 C.
Comparative Example E
In similar fashion to Comparative Example A, 445.28 g (4.275 mol) 2,2-dimethyl-1,3--propanediol, 70.15 g(1.13 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 794.98 g (4.785 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 47.35 g isophthalic acid, 41.65 g adipic acid, and 49.08 g cyclohexane-1,4-dicarboxylic acid (0.285 mol each). The finished resin has the following characteristics: AN
27.5, HN 3.7, Tg about 56.0 C.
Comparative Example F
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 38.49 g(0.62 mol) ethylene glycol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 777.54 g (4.68 mol) terephthalic acid are converted to a hydroxy-functional polyester resin in a first reaction stage.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 58.46 g adipic acid (0.40 mol). The finished resin has the following characteristics: AN 34.6, HN 4.5, Tg about 55.5 C.
Comparative Example G
In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 36.94 g (0.595 mol) ethylene glycol, 2.95 g (0.025 mol) 1,6-hexanediol, 0.1%, in reference to the total amount of finished. resin, of an Sn-containing catalyst and 777.54 g (4.68 mol) terephthalic acid are converted to a hydroxy-functional polyester resin in a first reaction stage.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 58.46 g adipic acid (0.40 mol). The finished resin has the following characteristics: AN 34.4, HN 3.1, Tg about 55.0 C.
Example 1 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethylene glycol, 32.29 g (0.31 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finishedl resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.2, HN 3.8, Tg about 56.0 C.
Example 2 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethylene glycol, 36.64 g (0.31 mol) 3-methyl-1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g isophthalic acid (0.77 mol) and 29.23 g adipic acid (0.20 mol).
The finished resin has the following characteristics: AN 34.0, HN 3.8, Tg about 55.5 C.
Example 3 In similar fashion to Comparative Example A, 472.89 g (4.54 mol) 2,2-dimethyl-1,3--propanediol, 24.83 g (0.40 mol) ethylene glycol, 41.66 g (0.40 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished. resin, of an Sn-containing catalyst, and 792.49 g (4.77 mol) terephthalic acid are converted in a first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 56.49 g (0.34 mol) isophthalic acid, 68.88 g (0.40 mol) cyclohexane-1,4-dicarboxylic acid and 24.84 g adipic acid (0.17 mol). The finished resin has the following characteristics: AN 34.3, HN 4.1, Tg about 55.0 C.
Example 4 In similar fashion to Comparative Example A, 472.89 g (4.54 mol) 2,2-dimethyl-1,3--propanediol, 24.83 g (0.40 mol) ethylene glycol, 20.83 g (0.20 mol) 1,5-pentanediol, 23.64 g (0.20 mol) 3-methyl-1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 792.49 g (4.77 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 56.49 g (0.34 mol) isophthalic acid, 68.88 g (0.40 mol) cyclohexane-1,4-dicarboxylic acid, and 24.84 g(0.17 mol) adipic acid. The finiished resin has the following characteristics: AN 34.3, HN 4.1, Tg about 55.0 C.
Example 5 In similar fashion to Comparative Example A, 475.49 g (4.565 mol) 2,2-dimethyl-1,3--propanediol, 19.24 g (0.31 mol) ethyleine glycol, 25.00 g (0.24 mol) 1,5-pentanediol, 18.91 g (0.16 mol) 3-methyl-1,5-pentanediol, 5.90 g (0.044 mol) trimethylolpropane, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 782.52 g (4.71 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 127.93 g (0.77 mol) isophthalic acid, and 29.23 g (0.20 mol) adipic acid.
The finished resin has the following characteristics: AN 34.3, HN 3.8, Tg about 54.0 C.
Example 6 In similar fashion to Comparative Example A, 444.76 g (4.27 mol) 2,2-dimethyl-1,3--propanediol, 38.49 g (0.62 mol) ethylene glycol, 46.87 g (0.45 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 810.76 g (4.88 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 137.76 g (0.80 mol) cyclohexane-1,4-dicarboxylic acid. The finished resin has the following characteristics: AN 33.5, HN 3.0, Tg about 52.5 C.
Example 9 In similar fashion to Comparative Example A, 469.24 g (4.505 mol) 2,2-dimethyl-1,3--propanediol, 27.94 g (0.45 mol) ethylene glycol, 46.87 g (0.45 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished. resin, of an Sn-containing catalyst, and 808.27 g (4.865 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 103.84 g isophthalic acid (0.625 mol) and 14.61 g adipic acid (0.10 mol).
The finished resin has the following characteristics: AN 27.3, HN 3.9, Tg about 57.5 C.
Example 10 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 36.94 g (0.595 mol) ethylene glycol, 2.61 g (0.025 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finishedi resin, of an Sn-containing catalyst, and 777.54 g (4.68 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 58.46 g adipic acid (0.40 mol). The finished resin has the following characteristics: AN 34.6, HN 3.8, Tg about 55.2 C.
Example 11 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 33.83 g (0.545 mol) ethylene glycol, 7.81 g (0.075 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of finished resin, of an Sn-containing catalyst, and 794.15 g (4.78 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g isophthalic acid (0.60 mol) and 43.84 g adipic acid (0.30 mol). The finished resin has the following characteristics: AN 34.2, HN 4.2, Tg about 55.0 C.
Example 12 In similar fashion to Comparative Example A, 491.64 g (4.72 mol) 2,2-dimethyl-1,3--propanediol, 28.87 g(0.465 mol) ethylene glycol, 16.14 g(0.155 mol) 1,5-pentanediol, 0.1%, in reference to the total amount of fmished resin, of an Sn-containing catalyst, and 794.15 g (4.78 mol) terephthalic acid are converted in the first reaction stage to a hydroxy-functional polyester resin.
This is converted to the finished polyester resin in the described manner with the addition of 99.68 g (0.60 mol) isophthalic acid and 43.84 g (0.30 mol) adipic acid. The fuushed resin has the following characteristics: AN 33.8, HN 3.0, Tg about 54 C.
Production of coating powders All coating powders listed in the tables can be produced according to the following formulations:
a) Coating powders crosslinked with P-hydroxyalkylamide:
Raw material Parts by weiQht Polyester resin 61.86 Primid XL-552 3.26 Bylr364 P (Byk Chemie) 1.30 Benzoin 0.20 Titan 23 10 (Kronos) 31.48 b) Coating powders crosslinked with polyepoxide:
Parts by weight Parts by weight Comparative Examples A, B, C Comparative Example E
Raw material Examples 1-4, 6 Example 9 Polyester resin 59.48 58.18 TM
Araldit PT 810 4.48 -TM
Araldit PT 910 - 4.68 DT 3126 (CIBA) 1.16 2.26 BykM364 P (Byk Chemie) 1.30 1.30 Benzoin 0.20 0.20 Titaii 2310 (Kronos) 31.48 31.48 The formulation components are mixed dry in a Henschel mixer at 700 rpm for 30 seconds and then extruded on a Buss Co. kneader (PLK 46) at a surface temperature of 100 C.
The obtained extrudate is cooled, crushed, ground and screened to a particle fineness of <90 m.
The coating tests occur on yellow chrome-plated aluminum sheets Al Mg 1 F 13, mill finish, thickness 0.7 mm at a stoving ternperature of 180 C and stoving time of 10 minutes (object temperature). The coating film thickness is about 80 m.
To simulate aging the coated sheets are exposed for a period of 4 weeks to an alternating climate: 4 days each at room climate (23 2 C, about 50% relative humidity) and 3 days at 55 C
in a heating cabinet. This cycle is repeated, the coated test sheets being subjected at weekly intervals at room temperature to the ball impact test according to ASTM D
2794, ball diameter '/z" at a maximum of 70 inch pound (maximum possible deformation of the sheet which still does not lead to cracking) in order to evaluatc, the flexibility of the coatings.
After performing the last such test series, the test sheets are stored for 24 hours in a refrigerator and then investigated for impact strength again at 8 C.
To test the weather resistance, the test sheets are weathered in the Q-panel accelerated weathering tester according to ASTM G 53-77 using UVB-313 lamps from the apparatus manufacturer (The Q-Panel Company) for 168 hours (formulations that contain (3-hydroxyalkyl-amide) for 336 hours (formulations containing polyepoxide). The conditions are as follows:
4 h UV at 60 C and 4 h condensation at 45 C with continuous alternation. To evaluate the weathering resistance of the test specimen, their initial and final luster according to Gardner are compared, measured under 60 .
The following tables show the obtained results a) for coating powders crosslinked with (3-hydroxyalkylamide and b) for coating powders crosslinked with polyepoxides:
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Claims (27)
1. A coating powder formulation, comprising:
(a) at least one carboxyl-functional polyester resin with an acid number of from 15 to 70 mg KOH/g of the polyester resin, a hydroxyl number of 10 or less mg KOH/g of the polyester resin and a glass transition temperature of at least 35°C, wherein:
(i) the polyester resin composed of difunctional monomers comprises at least one dicarboxylic acid and at least one diol monomer, (ii) the polyester resin contains a maximum of 80 mol% of isophthalic acid relative to the total amount of all dicarboxylic acids, (iii) the polyester resin contains at least 20 mol% of at least one dicarboxylic acid selected from the group consisting of an aromatic dicarboxylic acid with 8 to 16 carbon atoms, an aliphatic dicarboxylic acid with 4 to 22 carbon atoms, a cycloaliphatic dicarboxylic acid with 8 to 16 carbon atoms, a dimerized fatty acid and a mixture thereof, relative to the total amount of all dicarboxylic acids, (iv) the polyester resin contains at least 50 mol%
of at least one branched aliphatic diol with 4 to 12 carbon atoms, a maximum of 50 mol% of at least one diol selected from the group consisting of a linear aliphatic diol with 2 to 22 carbon atoms, a cycloaliphatic diol with 6 to 16 carbon atoms and a mixture thereof, relative to the total amount of all diols, and (v) the polyester resin contains among the diols 1,5-pentanediol or 1,5-pentanediol with one or more side alkyl substituents at a total molar concentration of from 0.5 to 30% relative to the amount of all diols present;
and (b) at least one organic compound curing agent which reacts with the carboxyl groups of the polyester resin to produce covalent bonds.
(a) at least one carboxyl-functional polyester resin with an acid number of from 15 to 70 mg KOH/g of the polyester resin, a hydroxyl number of 10 or less mg KOH/g of the polyester resin and a glass transition temperature of at least 35°C, wherein:
(i) the polyester resin composed of difunctional monomers comprises at least one dicarboxylic acid and at least one diol monomer, (ii) the polyester resin contains a maximum of 80 mol% of isophthalic acid relative to the total amount of all dicarboxylic acids, (iii) the polyester resin contains at least 20 mol% of at least one dicarboxylic acid selected from the group consisting of an aromatic dicarboxylic acid with 8 to 16 carbon atoms, an aliphatic dicarboxylic acid with 4 to 22 carbon atoms, a cycloaliphatic dicarboxylic acid with 8 to 16 carbon atoms, a dimerized fatty acid and a mixture thereof, relative to the total amount of all dicarboxylic acids, (iv) the polyester resin contains at least 50 mol%
of at least one branched aliphatic diol with 4 to 12 carbon atoms, a maximum of 50 mol% of at least one diol selected from the group consisting of a linear aliphatic diol with 2 to 22 carbon atoms, a cycloaliphatic diol with 6 to 16 carbon atoms and a mixture thereof, relative to the total amount of all diols, and (v) the polyester resin contains among the diols 1,5-pentanediol or 1,5-pentanediol with one or more side alkyl substituents at a total molar concentration of from 0.5 to 30% relative to the amount of all diols present;
and (b) at least one organic compound curing agent which reacts with the carboxyl groups of the polyester resin to produce covalent bonds.
2. The coating powder formulation according to claim 1, wherein (vi) the polyester resin further comprises at least one hydroxycarboxylic acid.
3. The coating powder formulation according to claim 1 or 2, wherein the at least one branched aliphatic diol with 4 to 12 carbon atoms contains an ester group.
4. The coating powder formulation according to any one of claims 1 to 3, wherein the 1,5-pentanediol with one or more side alkyl substituents is 3-methyl-1,5-pentanediol.
5. The coating powder formulation according to any one of claims 1 to 4, wherein:
(ii) the polyester resin contains a maximum of 61.5 mol% of isophthalic acid relative to the total amount of all dicarboxylic acids, (iii) the polyester resin contains at least 38.5 mol% of at least one dicarboxylic acid as defined in (iii) of claim 1; and (b) is at least one .beta.-hydroxyalkylamide.
(ii) the polyester resin contains a maximum of 61.5 mol% of isophthalic acid relative to the total amount of all dicarboxylic acids, (iii) the polyester resin contains at least 38.5 mol% of at least one dicarboxylic acid as defined in (iii) of claim 1; and (b) is at least one .beta.-hydroxyalkylamide.
6. The coating powder formulation according to any one of claims 1 to 4, wherein (b) is at least one polyepoxide.
7. The coating powder formulation according to any one of claims 1 to 5, wherein (b) is a .beta.-hydroxyalkylamide with at least two .beta.-hydroxyalkylamide groups.
8. The coating powder formulation according to claim 7, wherein (b) is bis[N,N'-di(.beta.-hydroxyethyl)]adipamide or bis[N,N'-di(.beta.-hydroxypropyl)]adipamide.
9. The coating powder formulation according to any one of claims 1 to 4 and 6, wherein (b) is a monomeric or polymeric polyepoxide with at least two epoxide groups.
10. The coating powder formulation according to claim 9, wherein (b) is a glycidyl ester of a monomeric polycarboxylic acid, which is terephthalic acid, trimellitic acid or a combination thereof.
11. The coating powder formulation according to claim 10, wherein the polycarboxylic acid is a combination of terephthalic acid and trimellitic acid in a ratio of about 3:1.
12. The coating powder formulation according to claim 9, wherein (b) is a glycidyl ether of cyanuric acid or isocyanuric acid.
13. The coating powder formulation according to claim 12, wherein (b) is triglycidyl isocyanurate, tris-(.beta.-methylglycidyl)isocyanurate or a combination thereof.
14. The coating powder formulation according to claim 9, wherein (b) is a glycidyl ester of a carboxy-functional polyester resin, a glycidyl-functional polyacrylate or a combination thereof.
15. The coating powder formulation according to any one of claims 1 to 14, wherein the polyester resin contains up to 30 mol% isophthalic acid, relative to the total amount of all dicarboxylic acids.
16. The coating powder formulation according to any one of claims 1 to 15, wherein the polyester resin at an isophthalic acid content of at least 10 mol%, relative to the total amount of all dicarboxylic acids of the polyester resin, has an .alpha.,.omega.-diol with five carbon atoms in sequence between the hydroxyl groups.
17. The coating powder formulation according to any one of claims 1 to 16, further comprising:
(c) an additive, a pigment, a filler or a mixture thereof.
(c) an additive, a pigment, a filler or a mixture thereof.
18. The coating powder formulation according to claim 17, wherein (c) is an inorganic or organic pigment, a filler, a wax or wax derivative, a micronized plastic, a flow control agent, a degassing auxiliary, an oxidation stabilizer, a light protection agent in the form of an UV
absorber, a HALS compound, or a mixture thereof, an accelerator, a silica oxide, an aluminum oxide or a mixture thereof to improve flowability, or a tribo additive.
absorber, a HALS compound, or a mixture thereof, an accelerator, a silica oxide, an aluminum oxide or a mixture thereof to improve flowability, or a tribo additive.
19. The coating powder formulation according to claim 18, wherein the micronized plastic is a polyamide, a polyethylene, a polypropylene or a polytetrafluoroethylene.
20. The coating powder formulation according to any one of claims 1 to 19, wherein (iv) further comprises a dimerized fatty alcohol.
21. The carboxyl-functional polyester resin (a) as defined in any one of claims 1 to 5, 15, 16 and 20.
22. Use of the carboxyl-functional polyester resin as defined in claim 21, for producing a coating powder formulation.
23. Use of the coating powder formulation as defined in any one of claims 1 to 20, for producing a protective layer or a coating on an object by electrostatic coating or fluidized bed coating.
24. Use according to claim 23, wherein the protective layer or coating is stoved on the object at a temperature from 120 to 220°C.
25. Use according to claim 24, wherein the temperature is from 130 to 200°C.
26. Use according to claim 25, wherein the temperature is from 140 to 160°C.
27. A method for producing a thermosetting coating powder formulation from the carboxyl-functional polyester resin as defined in any one of claims 1 to 5, 15, 16 and 20, comprising adding at least one .beta.-hydroxyalkylamide or polyepoxide and optionally (c) as defined in claim 17, 18 or 19, to the resin and wherein the resulting mass is then extruded at 80 to 130°C, discharged, granulated, ground and screened to a particle size of <100 µm.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ATA1726/98 | 1998-10-15 | ||
| AT172698A AT410095B (en) | 1998-10-15 | 1998-10-15 | Carboxy-functional polyester resin used in powder lacquer formulation is based on dicarboxylic acids and diols including pentan-1,5-diol, diethylene glycol and/or derivatives with alkyl side chains |
| ATA2054/98 | 1998-12-07 | ||
| AT205498A AT411687B (en) | 1998-12-07 | 1998-12-07 | Carboxy-functional polyester resin used in powder lacquer formulation is based on dicarboxylic acids and diols including pentan-1,5-diol, diethylene glycol and/or derivatives with alkyl side chains |
| PCT/AT1999/000243 WO2000023530A1 (en) | 1998-10-15 | 1999-10-12 | Thermosetting powder coating systems |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2346963A1 CA2346963A1 (en) | 2000-04-27 |
| CA2346963C true CA2346963C (en) | 2009-12-08 |
Family
ID=25596653
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002346963A Expired - Lifetime CA2346963C (en) | 1998-10-15 | 1999-10-12 | Thermosetting powder coating systems |
Country Status (10)
| Country | Link |
|---|---|
| EP (1) | EP1121394B1 (en) |
| CN (1) | CN1323333A (en) |
| AU (1) | AU6318599A (en) |
| CA (1) | CA2346963C (en) |
| CZ (1) | CZ297599B6 (en) |
| DE (1) | DE59910302D1 (en) |
| EG (1) | EG22520A (en) |
| MY (1) | MY122177A (en) |
| TW (1) | TW568943B (en) |
| WO (1) | WO2000023530A1 (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6555226B1 (en) * | 2000-10-26 | 2003-04-29 | Bp Corporation North America Inc. | Polyester resin for powder coating |
| AU2005201902B2 (en) * | 2004-05-11 | 2010-12-09 | Bluescope Steel Limited | Oxidation resistant coating |
| US7775716B2 (en) | 2004-05-26 | 2010-08-17 | Kee Plastics Ab | Piping bag, blank for manufacturing a piping bag and method of manufacturing a piping bag |
| CN100572472C (en) * | 2008-01-04 | 2009-12-23 | 扬州三得利化工有限公司 | A kind of polyester resin powder paint solidifying agent |
| WO2011068195A1 (en) * | 2009-12-04 | 2011-06-09 | 株式会社クラレ | Polyester fibers dyeable at ordinary pressure and process for producing same |
| US10179867B2 (en) | 2011-03-25 | 2019-01-15 | Dsm Ip Assets B.V. | Resin compositions for thermosetting powder coating compositions |
| MX2015010075A (en) * | 2013-02-08 | 2016-01-25 | Valspar Sourcing Inc | Ultra low cure powder coating. |
| CN103483989A (en) * | 2013-09-03 | 2014-01-01 | 安徽精一机械设备有限公司 | Water-boiling-resistant powder paint |
| CN106574042B (en) * | 2014-07-25 | 2020-02-18 | 帝斯曼知识产权资产管理有限公司 | Matt powder coating |
| CN105424612A (en) * | 2015-11-27 | 2016-03-23 | 辽宁凯迈石化有限公司 | Paraffin storage light stability detection device |
| CN114085363B (en) * | 2021-12-13 | 2023-01-03 | 安徽神剑新材料股份有限公司 | Polyester resin for high-filling powder coating, preparation method of polyester resin and high-filling powder coating |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3894115A (en) * | 1973-01-15 | 1975-07-08 | Chevron Res | Unsaturated polyesters having high impact strength and low water absorption |
| GB1509043A (en) * | 1975-04-29 | 1978-04-26 | Ucb Sa | Powdered epoxy resin and polyester coating compositions |
| NL8204206A (en) * | 1982-10-29 | 1984-05-16 | Dsm Resins Bv | POWDER COAT. |
| IT1231772B (en) * | 1989-08-02 | 1991-12-21 | Hoechst Sara Spa | PROCEDURE FOR THE COATING OF SUBSTRATES THROUGH HIGH TEMPERATURE AND SHORT TIME THERMOSETTING POWDER PAINTS. |
| KR950012768B1 (en) * | 1989-12-28 | 1995-10-21 | 고려화학주식회사 | Process for the preparation of low lemperatire curing polyester resin and powder paint composition |
| DE4305990A1 (en) * | 1993-02-26 | 1994-09-01 | Hoechst Ag | Acid-modified polyester and its use in stoving lacquers |
| DE4335845C3 (en) * | 1993-10-20 | 2001-06-13 | Inventa Ag | Thermosetting coating composition, its production and use |
| ATE259842T1 (en) * | 1996-07-12 | 2004-03-15 | Inventa Ag | POLYESTERS CONTAINING BETA-HYDROXYALKYLAMIDE GROUPS, THEIR PRODUCTION AND THEIR USE |
-
1999
- 1999-10-12 CA CA002346963A patent/CA2346963C/en not_active Expired - Lifetime
- 1999-10-12 DE DE59910302T patent/DE59910302D1/en not_active Expired - Lifetime
- 1999-10-12 EP EP99950378A patent/EP1121394B1/en not_active Expired - Lifetime
- 1999-10-12 CZ CZ20011340A patent/CZ297599B6/en not_active IP Right Cessation
- 1999-10-12 CN CN 99812113 patent/CN1323333A/en active Pending
- 1999-10-12 AU AU63185/99A patent/AU6318599A/en not_active Abandoned
- 1999-10-12 WO PCT/AT1999/000243 patent/WO2000023530A1/en active IP Right Grant
- 1999-10-13 EG EG128199A patent/EG22520A/en active
- 1999-10-14 TW TW88117815A patent/TW568943B/en not_active IP Right Cessation
- 1999-10-14 MY MYPI9904440 patent/MY122177A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| TW568943B (en) | 2004-01-01 |
| AU6318599A (en) | 2000-05-08 |
| EG22520A (en) | 2003-03-31 |
| DE59910302D1 (en) | 2004-09-23 |
| CA2346963A1 (en) | 2000-04-27 |
| CZ20011340A3 (en) | 2001-12-12 |
| WO2000023530A1 (en) | 2000-04-27 |
| EP1121394A1 (en) | 2001-08-08 |
| EP1121394B1 (en) | 2004-08-18 |
| CN1323333A (en) | 2001-11-21 |
| MY122177A (en) | 2006-03-31 |
| CZ297599B6 (en) | 2007-02-07 |
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