CA2110235C - At least partially blocked organic polyisocyanates, a process for their preparation and their use in coating compositions - Google Patents
At least partially blocked organic polyisocyanates, a process for their preparation and their use in coating compositions Download PDFInfo
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- CA2110235C CA2110235C CA002110235A CA2110235A CA2110235C CA 2110235 C CA2110235 C CA 2110235C CA 002110235 A CA002110235 A CA 002110235A CA 2110235 A CA2110235 A CA 2110235A CA 2110235 C CA2110235 C CA 2110235C
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- organic polyisocyanate
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- polyisocyanate
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
- C08G18/72—Polyisocyanates or polyisothiocyanates
- C08G18/80—Masked polyisocyanates
- C08G18/8061—Masked polyisocyanates masked with compounds having only one group containing active hydrogen
- C08G18/8096—Masked polyisocyanates masked with compounds having only one group containing active hydrogen with two or more compounds having only one group containing active hydrogen
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/08—Processes
- C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
- C08G18/72—Polyisocyanates or polyisothiocyanates
- C08G18/80—Masked polyisocyanates
- C08G18/8061—Masked polyisocyanates masked with compounds having only one group containing active hydrogen
- C08G18/807—Masked polyisocyanates masked with compounds having only one group containing active hydrogen with nitrogen containing compounds
- C08G18/808—Monoamines
-
- 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
- C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
- C09D175/04—Polyurethanes
Abstract
The present invention relates to organic polyisocyanates which have a content of unblocked and blocked isocyanate groups (calculated as NCO) of 5 to 20 wt.%, preferably 7 to 15 wt.%, wherein at least 95%, preferably 100%, of the isocyanate groups are present in blocked form and wherein the blocking agent contains A) 30 to 70 equivalent-% of diisopropylamine, B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B), wherein the percentages of A), B) and C) add up to 100.
The present invention also relates to a process for the production of these organic polyisocyanates and their use as crosslinking agents for organic polyhydroxyl compounds in polyurethane coating compositions.
The present invention also relates to a process for the production of these organic polyisocyanates and their use as crosslinking agents for organic polyhydroxyl compounds in polyurethane coating compositions.
Description
~~ ~_ ~ '~~~', ~ ~ Mo3982 L.eA 29 462-US
AT LEAST PARTIALLY BLOCKED ORGANIC
POLYISOCYANATES, A PROCESS FOR THEIR
PREPARATION AND THEIR USE IN COATING COMPOSITIONS
BACKGROUND OF THE INVENTION
Field of the Invention The present invention relates to novel organic polyisocyanates having predominantly or entirely blocked isocyanate groups, in which at least two different blocking agents are present, to a process for their production and to their use as crosslinking agents in heat curable, polyurethane coating compositions.
Description of the Prior Art Blocking organic polyisocyanates with blocking agents and the use of the blocked polyisocyanates as a crossiinking resin for polyurethane baking lacquers are known. Thus, for example, S. Petersen in Liebigs Ann. Chem. 562 (1949), p. 205 et seq mentions the possibility of blocking 1,6-diisocyanatohexane with blocking agents such as malonic acid diethyl ester, acetoacetic acid diethyl ester or piperidine. However, the resultant reaction products display a marked tendency to crystallize and for this reason alone are unusable as crosslinking resins for baking lacquers dissolved in lacquer solvents.
DE-OS 2,436,872 describes liquid, blocked polyisocyanates, which are prepared from isophorone diisocyanate and malonic acid esters.
Analogous liquid polyisocyanates are also described in DE-OS
3,001,060. These are malonic or acetoacetic ester blocked trimers of isophorone diisocyanate with isocyanurate groups. The use of such polyisocyanates which are entirely blocked with CH-acid esters as crosslinking resins for polyhydroxyl compounds results, after crosslinking, in an amide-ester compound instead of urethane groups as is known from Wicks, Kostyk J. Coat. Techn. 49, 1977, p. 77. This is also apparent LeA 29 462-US
. 6~ ~ ~.. ~ v' ~' from slightly poorer properties of the resulting coatings and, in particular, in reduced storage stability of the coating compositions (c.f. examples 10 and 11 ).
EP-A-0,096,210 describes one-component binders wherein the isocyanate component is blocked entirely with secondary amines, for example diisopropylamine. Based on the disclosure, these blocked polyisocyanates are primarily useful as solid products for powder coating applications.
EP-A-0,125,438 also describes one-component binders wherein the isocyanate component is blocked with secondary amines. Since, as may be seen from the examples, the intermediately produced isocyanate components are formulated into the ready-to-use lacquers, it is not apparent to what extent these isocyanate components are stable in terms of crystallization.
DE-OS 2,812,252 describes polyisocyanate crosslinking agents blocked with 1,2,4-triazole. Again, the emphasis is on the production of powder coatings. Polyisocyanates blocked with 1,2,4-triazole generally have a marked tendency to crystallize.
EP-A-0,403,044 describes blocked polyisocyanates with at least two blocking agents wherein the unblocking temperatures are at least 40°C apart. The intended objective is step-wise crosslinking. The disclosed blocking agents include E-caprolactam, oximes and butanol, which crosslink at significantly above 150°C.
The industrially and economically important polyisocyanates having isocyanurate groups and prepared from 1,6-diisocyanatohexane have to date remained without commercial importance when blocked with blocking agents which are released at low temperatures such as malonic esters or diisopropylamine. This is because, when dissolved in lacquer Mo3982 ~~~~~3~
AT LEAST PARTIALLY BLOCKED ORGANIC
POLYISOCYANATES, A PROCESS FOR THEIR
PREPARATION AND THEIR USE IN COATING COMPOSITIONS
BACKGROUND OF THE INVENTION
Field of the Invention The present invention relates to novel organic polyisocyanates having predominantly or entirely blocked isocyanate groups, in which at least two different blocking agents are present, to a process for their production and to their use as crosslinking agents in heat curable, polyurethane coating compositions.
Description of the Prior Art Blocking organic polyisocyanates with blocking agents and the use of the blocked polyisocyanates as a crossiinking resin for polyurethane baking lacquers are known. Thus, for example, S. Petersen in Liebigs Ann. Chem. 562 (1949), p. 205 et seq mentions the possibility of blocking 1,6-diisocyanatohexane with blocking agents such as malonic acid diethyl ester, acetoacetic acid diethyl ester or piperidine. However, the resultant reaction products display a marked tendency to crystallize and for this reason alone are unusable as crosslinking resins for baking lacquers dissolved in lacquer solvents.
DE-OS 2,436,872 describes liquid, blocked polyisocyanates, which are prepared from isophorone diisocyanate and malonic acid esters.
Analogous liquid polyisocyanates are also described in DE-OS
3,001,060. These are malonic or acetoacetic ester blocked trimers of isophorone diisocyanate with isocyanurate groups. The use of such polyisocyanates which are entirely blocked with CH-acid esters as crosslinking resins for polyhydroxyl compounds results, after crosslinking, in an amide-ester compound instead of urethane groups as is known from Wicks, Kostyk J. Coat. Techn. 49, 1977, p. 77. This is also apparent LeA 29 462-US
. 6~ ~ ~.. ~ v' ~' from slightly poorer properties of the resulting coatings and, in particular, in reduced storage stability of the coating compositions (c.f. examples 10 and 11 ).
EP-A-0,096,210 describes one-component binders wherein the isocyanate component is blocked entirely with secondary amines, for example diisopropylamine. Based on the disclosure, these blocked polyisocyanates are primarily useful as solid products for powder coating applications.
EP-A-0,125,438 also describes one-component binders wherein the isocyanate component is blocked with secondary amines. Since, as may be seen from the examples, the intermediately produced isocyanate components are formulated into the ready-to-use lacquers, it is not apparent to what extent these isocyanate components are stable in terms of crystallization.
DE-OS 2,812,252 describes polyisocyanate crosslinking agents blocked with 1,2,4-triazole. Again, the emphasis is on the production of powder coatings. Polyisocyanates blocked with 1,2,4-triazole generally have a marked tendency to crystallize.
EP-A-0,403,044 describes blocked polyisocyanates with at least two blocking agents wherein the unblocking temperatures are at least 40°C apart. The intended objective is step-wise crosslinking. The disclosed blocking agents include E-caprolactam, oximes and butanol, which crosslink at significantly above 150°C.
The industrially and economically important polyisocyanates having isocyanurate groups and prepared from 1,6-diisocyanatohexane have to date remained without commercial importance when blocked with blocking agents which are released at low temperatures such as malonic esters or diisopropylamine. This is because, when dissolved in lacquer Mo3982 ~~~~~3~
solvents, such blocked polyisocyanates are not stable in storage (see also comparative examples 1 and 2).
An object of the present invention is to provide novel, blocked lacquer polyisocyanates which may be used for the production of baking lacquers which have a maximum baking temperature of 140°C and which may be dissolved in known lacquer solvents to produce storage stable solutions.
This object may be achieved with the polyisocyanates according to the invention which are described in greater detail below.
SUMMARY OF THE INVENTION
The present invention relates to organic polyisocyanates which have a content of unblocked and blocked isocyanate groups (calculated as NCO) of 5 to 20 wt.%, preferably 7 to 15 wt.%, wherein at least 95%, preferably 100%, of the isocyanate groups are present in blocked form and wherein the blocking agent contains A) 30 to 70 equivalent-% of diisopropylamine, B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B), wherein the percentages of A), B) and C) add up to 100.
The present invention also relates to a process for the production of these organic polyisocyanates by reacting at 20 to 120°C at least 95 equivalent-% of the isocyanate groups of the polyisocyanates with a blocking agent mixture containing, based on the total equivalents of blocking agents, A) 30 to 70 equivalent-% of diisopropylamine, Mo3982 -4- ~~.~~1 B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B).
The present invention finally relates to the use of the blocked polyisocyanates as crosslinking agents for organic polyhydroxyl compounds in polyurethane coating compositions.
DETAILED DESCRIPTION OF THE INVENTION
The polyisocyanates from which the blocked polyisocyanates according to the invention are prepared are known from polyurethane chemistry and include polyisocyanates having aliphatically, cycloaliphatically and/or aromatically bound isocyanate groups and an isocyanate content of 30 to 50 wt.%. Examples include 1,6-diisocyanatohexane; 1-isocyanato-3,3,5-trimethyl-5-isocyanato-methylcyclohexane (isophorone diisocyanate or IPDI); 4,4'-diisocyanato-dicyclohexylmethane; 2,4- andlor 2,6-diisocyanatotoluene; 4.4'-diiso-cyanatodiphenylmethane; mixtures thereof with up to 50 wt.%, preferably up to 40 wt.%, based on the weight of the mixture, of 2,4'-diisocyanato-diphenylmethane and up to 5 wt.%, based on the weight of the mixture, of 2,2'-diisocyanatodiphenylmethane; and mixtures of the diisocyanato-diphenylmethane isomers with their higher homologs having more than two isocyanate groups, wherein these mixtures preferably contain at least 80 wt.% of the diisocyanatodiphenylmethane isomers. Mixtures of the preceding polyisocyanates andlor other polyisocyanates may also be used.
Also suitable as starting material for the process according to the invention are derivatives of the monomeric diisocyanates having biuret, isocyanurate andlor uretidione groups, in particular those with Mo3982 aliphatically andlor cycloaliphatically bound isocyanate groups, and especially the corresponding derivatives of 1,6-diisocyanatohexane.
Particularly preferred starting materials for preparing the polyisocyanates according to the invention are, (i) derivatives of 1,6 diisocyanatohexane containing isocyanurate groups and having an NCO
content of 19 to 25 wt.%, (ii) mixtures of polyisocyanates (i) with 4,4'-diisocyanatodicyclohexylmethane in a weight ratio of 10:1 to 1:10, (iii) mixtures of polyisocyanates (i) with polyisocyanates containing isocyanurate groups, prepared from IPDI and having an NCO content of 17 to 20 wt.% in a weight ratio of 10:1 to 1:10 and (iv) commercial MDI
mixtures containing 75 to 80 wt.% of 4,4'-diisocyanatodiphenylmethane, 8 to 12 wt.% of 2,4'-diisocyanatodiphenylmethane, 0 to 3 wt.% of 2,2'-diisocyanatodiphenylmethane, wherein the remainder may optionally contain higher homologs of these diisocyanates.
The starting polyisocyanates may also be in prepolymer form by reacting the preceding polyisocyanates with polyhydric alcohols having an OH number of from 56 to 1900. To prepare the prepoly-mers 0,05 to 0,6 equivalents of OH compounds are reacted per equivalent of NCO groups. Examples of such polyols are 1,4-dihydroxybutane, 2-ethyl-1,3-hexanediol, tri- and tetrapropylene glycol, other polypropylene glycols or polypropylene glycol mixtures having the necessary OH number and the addition product of 2 moles of propylene carbonate onto 1 mole of hydrazine. Trifunctional polyols such as glycerol or trimethylol propane may also be used, optionally in admixture with the diols exemplified hereinbefore. Among the preferred prepolymers are those which are based on 2,4-diisocyanato toluene and a polyol mixture comprising (i) polypropylene glycol having an OH
number of from 56 to 112, (ii) from 50 to 150 OH-equivalent-%, based on (i), of diethylene glycol and (iii) from 150 to 250 OH-equivalent-%, Sa based on (i), of trimethylol propane and which are prepared at an NCO/OH-equivalent ratio of from 1,6:1 to 2:1. Prepolymer formation of the starting polyisocyanates may proceed either simultaneously with the blocking reaction, for example, by reacting the starting polyisocyanates with a mixture of blocking agents and polyol, or sequentially by reacting the starting polyisocyanate with the blocking agents and the polyol in any desired order. The blocking agents to be used in the process according to the -6- ~1~.~~~
invention contain, based on the total equivalents of blocking agent, 30 to 70, preferably 40 to 60, equivalent-% of blocking agent A), 30 to 70, preferably 40 to 60 equivalent-%, of blocking agent B) and 0 to 20, preferably 0, equivalent-% of blocking agent C).
Diisopropylamine is used as blocking agent A). Suitable blocking agents B) include (i) CH-acidic esters, preferably malonic acid diethyl ester or acetoacetic acid ethyl ester, and more preferably malonic acid diethyl ester, (ii) 1,2,4-triazole and (iii) mixtures of these blocking agents.
Other suitable blocking agents which may be used in conjunction with blocking agents A) and B) are known and include butanone oxime and E-caprolactam.
In accordance with the process according to the invention, the blocking agents are used in a quantity which corresponds to an equivalent ratio of blocking agent to isocyanate groups of the starting polyisocyanate, minus the isocyanate groups optionally required for in situ prepolymer formation with diols, of 0.95:1 to 1.2:1, preferably 1:1 to 1.1:1.
The process according to the invention is generally carried out at a temperature of 20 to 120°C, preferably 50 to 100°C, in the absence or the presence of solvents. Suitable solvents include n-butyl acetate, methoxypropyl acetate, toluene, xylene or higher aromatic solvent mixtures such as those sold by Exxon under the trade name Solvesso.
In a preferred embodiment the process according to the invention is carried out by introducing the liquid or dissolved isocyanate component into a vessel along with first portion of the blocking agent, for example component A). The reaction with diisopropylamine proceeds rapidly even at relatively low temperatures of, for example, 40°C. The calculated NCO
content is exactly reached. Then, the other portion of blocking agent, for Mo3982 -7- ~ l ~ ~ w e~.3 example component B), is added. If malonic acid esters are used, the total quantity of malonic ester is mixed with approx. 1.5% of a strong base, for example sodium methylate. This mixture is stirred into the partially blocked polyisocyanate such that a slightly exothermic reaction is observed. The reaction is continued at 70°C for approx. 1 to 2 hours until an NCO content is no longer detectable by IR spectrometry. The mixture is then adjusted to the desired viscosity with the previously disclosed solvents.
The predominantly or completely blocked polyisocyanates according to the invention are those with the previously disclosed characteristics. In general, these blocked polyisocyanates are used as 50 to 80 wt.%, preferably 60 to 75 wt.%, solutions in lacquer solvents. In the preferred embodiment for preparing the compounds according to the invention, the quantity of solvent is preferably selected in such a manner that such solutions are directly obtained.
In accordance with the invention, it is possible for the first time to convert practically any desired polyisocyanate into the corresponding blocked polyisocyanate, which are storage stable in conventional lacquer solvents and enable the production of baking lacquers having a maximum crosslinking temperature of 140°C. The "crosslinking temperature" means the temperature at which maximum crosslinking is observed after heating for 20 minutes in the presence of equivalent quantities of non-volatile alcoholic polyhydroxyl compounds. The cross-linking temperature of aliphatic polyisocyanates which are blocked according to the invention with equimolar quantities of diisopropylamine and 1,2,4-triazole is 139°C, without the addition of a catalyst.
Polyisocyanates according to the invention with aliphatically bound isocyanate groups which are blocked with an equimolar mixture of Mo3982 _g_ diisopropylamine and malonic acid diethyl ester have a crosslinking temperature of 130°C.
Compared with IPDI or IPDI derivatives exclusively blocked with malonic acid diethyl ester, the polyisocyanates according to the invention are not exclusively blocked with malonic acid diethyl ester so that when the compounds according to the invention are used as crosslinking agents for polyhydroxyl compounds at least some urethane groups are produced. Therefore, the technical properties of the resulting coatings are improved when compared to coatings containing only amide groups which are obtained from the use of prior art polyisocyanates exGusively blocked with CH-acid compounds. The proportion of amide groups, which impairs properties, is thus reduced to a tolerable level by using the compounds according to the invention. In addition, the storage stability of the coating compositions containing a polyisocyanate component which is partially blocked with CH-acidic esters and partially blocked with diisopropylamine, is distinctly improved (see comparative examples 10 and 11 ).
Further, the yellowing of coatings prepared from compositions containing the blocked polyisocyanates according to the invention is less than when polyisocyanates blocked with, for example, butanone oxime, are used.
The predominantly or completely blocked polyisocyanates according to the invention constitute valuable crosslinking resins for organic polyhydroxyl compounds in the production of baking lacquers.
They may be used in place of the blocked polyisocyanates previously used for this purpose. Suitable polyhydroxyl compounds for this purpose, together with further details relating to the production and use of such baking lacquers may be found in the relevant literature, for example Z.W. Wicks, Progr. Org. Coat. 9, 20 (applications) 1981.
Mo3982 ~2~~0235 _g_ In the following examples, all parts and percentages are by weight unless otherwise indicated.
EXAMPLES
Starting materials Polyisocyanate I:
An isocyanurate group-containing polyisocyanate prepared by the catalytic trimerization of 1,6-diisocyanatohexane and having an NCO
content of 21.5%, a monomeric 1,6-diisocyanato-hexane content of 0.2% and a viscosity (23°C) of 3000 mPa.s.
Polvisocvanate II:
4,4'-diisocyanatodicyclohexylmethane.
Polyisocyanate III:
A polyisocyanate mixture of the diphenylmethane series having an NCO content of 31.4% and containing 80% of 4,4'-diisocyanato-diphenylmethane, 9% of 2,4'-diisocyanato-diphenylmethane, 1 % of 2,2'-diisocyanatodiphenylmethane and 10% of higher functional homologs of these diisocyanates.
Polyisocyanate IV:
A 70% solution in Solvesso*100 solvent of an isocyanurate group-containing polyisocyanate prepared from IPDI and having an NCO
content of the solution of 11.6%.
Polyisocyanate V:
An isocyanurate group-containing polyisocyanate prepared from 1,6-diisocyanatohexane and having an NCO-content of 21.0%, a monomeric 1,6-diisocyanatohexane content of 0.1 % and a viscosity (23°C) of 3300 mPa.s.
Dihydroxy compound I:
An adduct prepared by adding 2 moles of propylene carbonate *trade-mark Mo3982 onto 1 mole of hydrazine and having the formula I .
Example 1 (Comparative example) Formulation:
195 g (1.0 equiv) polyisocyanate I
176 g (1.1 moles} malonic acid diethyl ester 2.7 g sodium methylate solution (30%) in methanol 160.1 g (70%) methoxypropyl acetate 533.8 g (1.0 equiv) blocked NCO groups Pertormance:
Polyisocyanate I was introduced into a vessel and stirred at room temperature. The distilled malonic ester and sodium methylate solution were stirred together in a glass beaker. This slightly turbid mixture was poured into the stirred polyisocyanate. An exothermic reaction was observed. The reacting mixture was heated to approx. 60°C. Using an oil bath, the temperature was raised to 70°C and the reaction was continued at this temperature for approx. 4 hours until the NCO band had disappeared from the IR spectrum. The reaction product was diluted with the solvent and an almost colorless, clear solution was obtained which had a viscosity of approx. 1000 mPa.s at 23°C.
After storage for approx. 1 week at room temperature, the viscosity of this solution increased dramatically. The solution became gel-like and finally solidified into a glassy, transparent gel after storage for 14 days storage. The product could be reliquefied by melting (approx. 60°C).
Mo3982 Example 2 (comparative example) Formulation:
195 g (1 equiv) polyisocyanate 1 106 g (1.05 moles) diisopropylamine 129 g (70%) methoxypropyl acetate 430 g (1.0 equiv) blocked NCO groups Pertormance:
Polyisocyanate I and solvent were introduced into a vessel.
Diisopropylamine was added dropwise at room temperature while the mixture was being stirred. The mixture was heated to 70°C for approx.
minutes to complete the reaction. No NCO content was detectable by IR
spectrometry. A colorless, clear solution having a viscosity at 23°C of approx. 6000 mPa.s was obtained. Over a period of several days, the solution started to flow in a gel-like manner down the sides of the vessel.
After two weeks, the product began to crystallize out into whitish crystals.
Example 3 (according to the invention) Formulation:
390 g (2.0 equiv) polyisocyanate I
160 g (1.0 mote) malonic acid diethyl ester 2.4 g sodium methylate solution (30%) 111.1 g (1.1 moles) diisopropylamine 284.4 g methoxypropyl acetate 947.9 g (2.0 equiv} blocked NCO groups Performance:
Polyisocyanate I was introduced into a vessel at room temperature and stirred. The mixture of malonic ester and sodium methylate solution was then added. On completion of addition, the temperature had risen to approx. 50°C. The mixture was heated to 70°C and stirred for a further Mo3982 ~~~~r 20 minutes. The measured NCO content was just below the calculated content of 7.6%. The mixture was diluted with methoxypropyl acetate and cooled to approx. 40°C, and diisopropylamine was added dropwise. 10 minutes after completion of the addition, no NCO content was detectable by IR spectrometry. A clear, almost colorless solution was obtained having a viscosity at 23°C of 2500 mPa.s and an NCO content in blocked form of 8.7%. The solution had a storage life of at least 6 months without crystallization.
Example 4 (according to the invention) Formulation:
195.0 g (1.0 equiv)polyisocyanate I
131.0 g (1.0 equiv) polyisocyanate II
75.8 g (0.75 moles) diisopropylamine 104.0 (0.8 moles) acetoacetic ester 2,p g sodium methylate solution (30%) 59.0 g (0.50 equiv) dihydroxy compound I
243.0 g (70%) butyl acetate 809.8 g (1.5 equiv) blocked NCO groups Pertormance:
Both polyisocyanates were introduced into a vessel in butyl acetate.
To the stirred solution was added dropwise the stated quantity of diiso-propylamine, wherein a slight exothermic reaction was observed. Then, the highly viscous, colorless dihydroxy compound I was added and the reaction mixture was heated to 100°C. After a reaction time of approx.
hours, the calculated NCO content of 4.5% was achieved. The mixture was cooled to 70°C and the solution of acetoacetic acid ethyl ester with sodium methylate was added in portions. After a reaction time of approx. 12 hours no NCO content was detectable by IR spectrometry. A clear, light yellow solution was obtained having a viscosity at 23°C of approx. 3000 mPa.s and an NCO
content in Mo3982 blocked form of 7.7%. The solution had a storage life of at least 6 months.
Example 5 (according to the invention) Formulation:
804.0 g (6.0 equiv) polyisocyanate III
336.0 g (3.0 equiv) of a polypropylene glycol with an OH
number of 500 240.0 g (1.5 moles) malonic acid diethyl ester 2.4 g sodium methylate solution (30%) 151.0 g (1.5 moles) diisopropylamine 654.0 g (approx. 30%) methoxypropyl acetate 2187.4 g (3.0 equiv) blocked NCO groups Performance:
Polyisocyanate III, solvent and polypropylene glycol (OH number 500) were introduced into a vessel and heated to 100°C while being stirred. After a reaction time of approx. 30 minutes, the calculated NCO
content of 7.0% was reached. The mixture was cooled to 70°C and the solution of malonic ester and sodium methylate was added in portions.
The mixture was stirred for approx. 1 hour at 70°C and the NCO
content was found to be slightly less than the calculated value of 3.09%.
Diisopropylamine was then added dropwise over 50 minutes without further heating. A sample shows no NCO content was detectable by IR
spectrometry. A reddish-brown, clear solution was obtained having a viscosity at 23°C of 6000 mPa.s. The blocked polyisocyanate solution had a storage life of at least 6 months without crystallization. The blocked NCO group content was 5.7%.
Mo3982 Example 6 (according to the invention) Formulation:
724 g (2.0 equiv) polyisocyanate IV
69 g (1.0 mole) 1,2,4-triazole 106 g (1.05 moles) diisopropylamine 343 g (55%) methoxypropyl acetate 1242 g (2.0 equiv) blocked NCO groups Performance:
Polyisocyanate IV was introduced into a vessel and mixed with the crystalline 1,2,4-triazole. The mixture was heated to 110°C while being stirred and reacted for approx. 3 hours until the calculated NCO content of 5.29% was reached. The mixture was then diluted with methoxypropyl acetate and cooled. At approx. 50°C, the diisopropylamine was added dropwise to the solution. A slight exothermic reaction was observed. On completion of diisopropylamine addition, no NCO content was detectable by IR spectrometry. The 55% solution of this blocked polyisocyanate had a viscosity at 23°C of 2300 mPa.s and an NCO content in blocked form of 6.76%. The solution had a storage life of at least 6 months without crystallization.
Example 7 (according to the invention) Formulation:
280.0 g (1.4 equiv) polyisocyanate V
362.0 g (1.0 equiv) polyisocyanate IV
69.0 g (1.0 mole) 1,2,4-triazole 101.0 g (1.0 mole) diisopropylamine 47.2 g (0.4 equiv) diol I
302.0 g (65%) methoxypropyl acetate 1161.2 g (2.0 equiv) blocked NCO groups Mo3982 Performance:
Both polyisocyanate components, the methoxypropyl acetate and the crystalline 1,2,4-triazole (flakes) were introduced into a vessel and heated to 100°C while being stirred. After approx. 30 minutes, the NCO
content of the reaction mixture had fallen to the calculated value of 4.1 %.
The mixture was cooled to 60°C, diisopropylamine was added dropwise and diol I added. The mixture was then reacted for approx. 2 hours at 100°C until no further NCO groups were detectable by IR spectroscopy.
A clear, light yellow solution of a co-blocked polyisocyanate was obtained. The solution had a storage life of at least 6 months without crystallization. The viscosity at 23°C was approx. 7800 mPa.s.
Example 8 (according to the invention) Formulation:
362.0 g (1.0 equiv) polyisocyanate IV
280.0 g (1.4 equiv) polyisocyanate V
156.0 g (1.2 moles) acetoacetic ester 1.2 g sodium methylate solution (30%) 121.2 g (1.2 moles) diisopropylamine 155.0 g methoxypropyl acetate 1055.4 (1.4 equiv) blocked NCO groups Performance:
The isocyanate mixture was blocked in a manner analogous to that described in Example 4. A clear, light yellow solution (75%) was obtained having a viscosity at 23°C of approx. 14,500 mPa.s and an NCO group content in blocked form of 9.3%. The solution had a storage life of at least 6 months without crystallization.
Mo3982 w 211035 Example 9 - Ready-to-spray, pigmented baking filler (according to the invention) 71.3 parts by weight of a polyester solution (I) present at 65%
solids in a mixture of Solvesso*100 solvent/isobutanol (weight ratio 31.5:3.5), having a hydroxyl content, based on solution, of 1.7%, an acid value of 5 and a viscosity of 2700 mPa.s at 23°C (Alkynol*1665, manufacturer: Bayer, Leverkusen) were combined with 216.4 parts by weight of barium sulphate (Blanc fixe micro* manufacturer. Sachtleben-Chemie, Duisberg), 54.1 parts by weight of titanium dioxide (Bayertitan*
R-KB-2, manufacturer: Bayer, Leverkusen), 18.0 parts by weight of a pigment (light blue 2 R, manufacturer: Bayer, Leverkusen), 3.6 parts by weight of a dispersing auxiliary (Antiterra U, present as a 50% solution, manufacturer: Byk-Chemie, Wesel), 3.6 parts by weight of silica gel (Aerosil*R 972, manufacturer: Degussa, Frankfurt am Main), 16.0 parts by weight of 1-methoxypropyl acetate-2, 15.9 parts by weight of butyl acetate and 15.9 carts by weight of xylene. The mixture was dispersed for 45 minutes in a bead mill (model: VSME, manufacturer: Vollrath, Cologne) such that the temperature of the material being dispersed did not exceed 50°C.
The resulting paste was combined by stirring with a further 171.7 parts by weight of polyester solution I, 80.5 parts by weight of a polyester solution (II) present at 80% solids in butyl acetate and having a hydroxyl content of 3.4%, an acid value of <_ 2 and a viscosity of 2500 to 3500 mPa.s at 23°C (Desmophen*670, 80%, manufacturer: Bayer, Leverkusen), 3.6 parts by weight of a flow control auxiliary (Byk*358, present as a 50% solution, manufacturer: Byk Chemie, Wesel), 81.4 parts by weight of an amino resin (Maprenai*MF 890, 62% in n-butanol, manufacturer: Cassella, Frankfurt am Main), 117.1 parts by weight of the *trade-mark Mo3982 _17_ polyisocyanate solution of Example 8, 43.6 parts by weight of 1-methoxypropyl acetate-2, 43.6 parts by weight of butyl acetate and 43.7 parts by weight of xylene.
The resulting coating composition was readily sprayable and displayed good flow-out on heat-resistant polyester film, glass, sheet iron and electrocoated sheet metal.
Solids content according to weighed portion: 65.6%.
Viscosity as draining time: 30 seconds in 4 mm DIN cup (DIN 53 211).
The coating composition was sufficiently reactive at a baking temperature of 130°C to cure without catalysis. Properties of the coating after baking for 30 minutes in a circulating air drying cabinet at 130°C:
Konig pendulum hardness: 142 sec (DIN 53 157) Erichsen indentation to DIN 53 156: 10.5 mm Dry film thicknesses of up to 45 Nm were achieved in a single operation without blistering or surface defects on electrocuted metal sheets (cathodically electrocuted metal sheet, lacquer test sheets from Mercedes Benz AG, Sindelfingen).
Within the coating structure, the filler exhibited good adhesion to the substrate (electrocoating) and good intercoat adhesion to basecoat and topcoat lacquers.
Stone impact testing:
A cathodically dipcoated t metal sheet was coated with the filler produced according to the invention (dry film thickness 35 Nm, baked for minutes at 130°C), overcoated with a commercial alkydlamino based 25 topcoat (Tornado*red, PPG, Wuppertal) and baked for 25 minutes at 155°C (dry film thickness 45 Nm). The coating displayed high resistance to stone impact when subjected to the VDA (Verband der Automobilindustrie = automotive industry association) stone impact test *trade-mark Mo3982 _18- 2~:~~~ ~~
(model 508, 2 times 500 g steel pellets, 1.5 bar), having a rating of 1 or 2 according to the prescribed VDA assessment method.
Storage stability:
After 3 months' storage at room temperature, the viscosity of the coating composition was unchanged.
After storage for 30 days in a drying cabinet at 50°C, the viscosity to DIN 53 211 (see above) had risen to a draining time of 42 seconds from a 4 mm DIN cup. The Konig pendulum hardness (see above) after baking in an circulating air drying cabinet (30 minutes at 130°C) was sec.
Example 10 (comparative example) Formulation:
362.0 g (1.0 equiv) poiyisocyanate IV
280.0 g (1.4 equiv) polyisocyanate V
156.0 g (1.2 moles) acetoacetic ester 192.0 g (1.2 moles) malonic acid diethyl ester 3.2 g sodium methylate solution (30%) 180.0 g methoxypropyl acetate 1173.2 g (2.4 equiv) blocked NCO groups Performance:
The polyisocyanates were combined while being stirred at room temperature with the mixture of the two CH-acidic esters and sodium methylate. Addition was made in portions, so that the exothermic reaction was controlled. On completion of the addition, the temperature of the reaction mixture had risen to approx. 60°C. The reaction was continued for a further 5 hours at 70°C, until the NCO band in the IR spectrum was scarcely detectable. The mixture was then diluted with methoxypropyl acetate. A clear, light yellow solution (approx. 75%) was obtained having Mo3982 -19- ~ 2 1 1 0 2 3 5 a viscosity at 23°C of approx. 10,000 mPa.s and an NCO group content in blocked form of 8.5°~.
Examele 11 - Comparison Example Comparison of increase in viscosity in clear lacquers a) According to the invention 503.6 parts by weight of polyester solution ( from Example 9 were combined with 226.4 parts by weight of the polyisocyanate solution from Example 8, 1.8 parts by weight of a flow control auxiliary (Byk*358), 178.8 parts by weight of 1-methoxypropyl acetate-2 and 89.4 parts by weight of xylene and homogenized by stirring.
(Blocked) NCO/OH ratio = 1Ø
Solids content according to weighed portion: approx. 49.8%
Viscosity as draining time: 30 sec (DIN 53 211).
b) Comparison Example 11 a) was repeated with the sole exception that the polyisocyanate Solution of Example 8 was substituted by the equivalent quantity of the polyisocyanate solution according to Example 10.
(Blocked) NCO/OH ratio = 1Ø
Solids content according to weighed portion: approx. 55.7%
Viscosity as draining time: 30 sec (DIN 53 211).
Storage at 50°C:
After storage for 14 days in a circulating air drying cabinet at 50°C, the viscosity (measured as draining time, see above) of coating composition 11 a) was 36 sec; after 30 days the draining time had not increased further. However, Coating composition 11 b) had a draining time of 60 sec after only 14 days.
Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is *trade-mark Mo3982 -20- 2~.1~23~
solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims.
Mo3982
An object of the present invention is to provide novel, blocked lacquer polyisocyanates which may be used for the production of baking lacquers which have a maximum baking temperature of 140°C and which may be dissolved in known lacquer solvents to produce storage stable solutions.
This object may be achieved with the polyisocyanates according to the invention which are described in greater detail below.
SUMMARY OF THE INVENTION
The present invention relates to organic polyisocyanates which have a content of unblocked and blocked isocyanate groups (calculated as NCO) of 5 to 20 wt.%, preferably 7 to 15 wt.%, wherein at least 95%, preferably 100%, of the isocyanate groups are present in blocked form and wherein the blocking agent contains A) 30 to 70 equivalent-% of diisopropylamine, B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B), wherein the percentages of A), B) and C) add up to 100.
The present invention also relates to a process for the production of these organic polyisocyanates by reacting at 20 to 120°C at least 95 equivalent-% of the isocyanate groups of the polyisocyanates with a blocking agent mixture containing, based on the total equivalents of blocking agents, A) 30 to 70 equivalent-% of diisopropylamine, Mo3982 -4- ~~.~~1 B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B).
The present invention finally relates to the use of the blocked polyisocyanates as crosslinking agents for organic polyhydroxyl compounds in polyurethane coating compositions.
DETAILED DESCRIPTION OF THE INVENTION
The polyisocyanates from which the blocked polyisocyanates according to the invention are prepared are known from polyurethane chemistry and include polyisocyanates having aliphatically, cycloaliphatically and/or aromatically bound isocyanate groups and an isocyanate content of 30 to 50 wt.%. Examples include 1,6-diisocyanatohexane; 1-isocyanato-3,3,5-trimethyl-5-isocyanato-methylcyclohexane (isophorone diisocyanate or IPDI); 4,4'-diisocyanato-dicyclohexylmethane; 2,4- andlor 2,6-diisocyanatotoluene; 4.4'-diiso-cyanatodiphenylmethane; mixtures thereof with up to 50 wt.%, preferably up to 40 wt.%, based on the weight of the mixture, of 2,4'-diisocyanato-diphenylmethane and up to 5 wt.%, based on the weight of the mixture, of 2,2'-diisocyanatodiphenylmethane; and mixtures of the diisocyanato-diphenylmethane isomers with their higher homologs having more than two isocyanate groups, wherein these mixtures preferably contain at least 80 wt.% of the diisocyanatodiphenylmethane isomers. Mixtures of the preceding polyisocyanates andlor other polyisocyanates may also be used.
Also suitable as starting material for the process according to the invention are derivatives of the monomeric diisocyanates having biuret, isocyanurate andlor uretidione groups, in particular those with Mo3982 aliphatically andlor cycloaliphatically bound isocyanate groups, and especially the corresponding derivatives of 1,6-diisocyanatohexane.
Particularly preferred starting materials for preparing the polyisocyanates according to the invention are, (i) derivatives of 1,6 diisocyanatohexane containing isocyanurate groups and having an NCO
content of 19 to 25 wt.%, (ii) mixtures of polyisocyanates (i) with 4,4'-diisocyanatodicyclohexylmethane in a weight ratio of 10:1 to 1:10, (iii) mixtures of polyisocyanates (i) with polyisocyanates containing isocyanurate groups, prepared from IPDI and having an NCO content of 17 to 20 wt.% in a weight ratio of 10:1 to 1:10 and (iv) commercial MDI
mixtures containing 75 to 80 wt.% of 4,4'-diisocyanatodiphenylmethane, 8 to 12 wt.% of 2,4'-diisocyanatodiphenylmethane, 0 to 3 wt.% of 2,2'-diisocyanatodiphenylmethane, wherein the remainder may optionally contain higher homologs of these diisocyanates.
The starting polyisocyanates may also be in prepolymer form by reacting the preceding polyisocyanates with polyhydric alcohols having an OH number of from 56 to 1900. To prepare the prepoly-mers 0,05 to 0,6 equivalents of OH compounds are reacted per equivalent of NCO groups. Examples of such polyols are 1,4-dihydroxybutane, 2-ethyl-1,3-hexanediol, tri- and tetrapropylene glycol, other polypropylene glycols or polypropylene glycol mixtures having the necessary OH number and the addition product of 2 moles of propylene carbonate onto 1 mole of hydrazine. Trifunctional polyols such as glycerol or trimethylol propane may also be used, optionally in admixture with the diols exemplified hereinbefore. Among the preferred prepolymers are those which are based on 2,4-diisocyanato toluene and a polyol mixture comprising (i) polypropylene glycol having an OH
number of from 56 to 112, (ii) from 50 to 150 OH-equivalent-%, based on (i), of diethylene glycol and (iii) from 150 to 250 OH-equivalent-%, Sa based on (i), of trimethylol propane and which are prepared at an NCO/OH-equivalent ratio of from 1,6:1 to 2:1. Prepolymer formation of the starting polyisocyanates may proceed either simultaneously with the blocking reaction, for example, by reacting the starting polyisocyanates with a mixture of blocking agents and polyol, or sequentially by reacting the starting polyisocyanate with the blocking agents and the polyol in any desired order. The blocking agents to be used in the process according to the -6- ~1~.~~~
invention contain, based on the total equivalents of blocking agent, 30 to 70, preferably 40 to 60, equivalent-% of blocking agent A), 30 to 70, preferably 40 to 60 equivalent-%, of blocking agent B) and 0 to 20, preferably 0, equivalent-% of blocking agent C).
Diisopropylamine is used as blocking agent A). Suitable blocking agents B) include (i) CH-acidic esters, preferably malonic acid diethyl ester or acetoacetic acid ethyl ester, and more preferably malonic acid diethyl ester, (ii) 1,2,4-triazole and (iii) mixtures of these blocking agents.
Other suitable blocking agents which may be used in conjunction with blocking agents A) and B) are known and include butanone oxime and E-caprolactam.
In accordance with the process according to the invention, the blocking agents are used in a quantity which corresponds to an equivalent ratio of blocking agent to isocyanate groups of the starting polyisocyanate, minus the isocyanate groups optionally required for in situ prepolymer formation with diols, of 0.95:1 to 1.2:1, preferably 1:1 to 1.1:1.
The process according to the invention is generally carried out at a temperature of 20 to 120°C, preferably 50 to 100°C, in the absence or the presence of solvents. Suitable solvents include n-butyl acetate, methoxypropyl acetate, toluene, xylene or higher aromatic solvent mixtures such as those sold by Exxon under the trade name Solvesso.
In a preferred embodiment the process according to the invention is carried out by introducing the liquid or dissolved isocyanate component into a vessel along with first portion of the blocking agent, for example component A). The reaction with diisopropylamine proceeds rapidly even at relatively low temperatures of, for example, 40°C. The calculated NCO
content is exactly reached. Then, the other portion of blocking agent, for Mo3982 -7- ~ l ~ ~ w e~.3 example component B), is added. If malonic acid esters are used, the total quantity of malonic ester is mixed with approx. 1.5% of a strong base, for example sodium methylate. This mixture is stirred into the partially blocked polyisocyanate such that a slightly exothermic reaction is observed. The reaction is continued at 70°C for approx. 1 to 2 hours until an NCO content is no longer detectable by IR spectrometry. The mixture is then adjusted to the desired viscosity with the previously disclosed solvents.
The predominantly or completely blocked polyisocyanates according to the invention are those with the previously disclosed characteristics. In general, these blocked polyisocyanates are used as 50 to 80 wt.%, preferably 60 to 75 wt.%, solutions in lacquer solvents. In the preferred embodiment for preparing the compounds according to the invention, the quantity of solvent is preferably selected in such a manner that such solutions are directly obtained.
In accordance with the invention, it is possible for the first time to convert practically any desired polyisocyanate into the corresponding blocked polyisocyanate, which are storage stable in conventional lacquer solvents and enable the production of baking lacquers having a maximum crosslinking temperature of 140°C. The "crosslinking temperature" means the temperature at which maximum crosslinking is observed after heating for 20 minutes in the presence of equivalent quantities of non-volatile alcoholic polyhydroxyl compounds. The cross-linking temperature of aliphatic polyisocyanates which are blocked according to the invention with equimolar quantities of diisopropylamine and 1,2,4-triazole is 139°C, without the addition of a catalyst.
Polyisocyanates according to the invention with aliphatically bound isocyanate groups which are blocked with an equimolar mixture of Mo3982 _g_ diisopropylamine and malonic acid diethyl ester have a crosslinking temperature of 130°C.
Compared with IPDI or IPDI derivatives exclusively blocked with malonic acid diethyl ester, the polyisocyanates according to the invention are not exclusively blocked with malonic acid diethyl ester so that when the compounds according to the invention are used as crosslinking agents for polyhydroxyl compounds at least some urethane groups are produced. Therefore, the technical properties of the resulting coatings are improved when compared to coatings containing only amide groups which are obtained from the use of prior art polyisocyanates exGusively blocked with CH-acid compounds. The proportion of amide groups, which impairs properties, is thus reduced to a tolerable level by using the compounds according to the invention. In addition, the storage stability of the coating compositions containing a polyisocyanate component which is partially blocked with CH-acidic esters and partially blocked with diisopropylamine, is distinctly improved (see comparative examples 10 and 11 ).
Further, the yellowing of coatings prepared from compositions containing the blocked polyisocyanates according to the invention is less than when polyisocyanates blocked with, for example, butanone oxime, are used.
The predominantly or completely blocked polyisocyanates according to the invention constitute valuable crosslinking resins for organic polyhydroxyl compounds in the production of baking lacquers.
They may be used in place of the blocked polyisocyanates previously used for this purpose. Suitable polyhydroxyl compounds for this purpose, together with further details relating to the production and use of such baking lacquers may be found in the relevant literature, for example Z.W. Wicks, Progr. Org. Coat. 9, 20 (applications) 1981.
Mo3982 ~2~~0235 _g_ In the following examples, all parts and percentages are by weight unless otherwise indicated.
EXAMPLES
Starting materials Polyisocyanate I:
An isocyanurate group-containing polyisocyanate prepared by the catalytic trimerization of 1,6-diisocyanatohexane and having an NCO
content of 21.5%, a monomeric 1,6-diisocyanato-hexane content of 0.2% and a viscosity (23°C) of 3000 mPa.s.
Polvisocvanate II:
4,4'-diisocyanatodicyclohexylmethane.
Polyisocyanate III:
A polyisocyanate mixture of the diphenylmethane series having an NCO content of 31.4% and containing 80% of 4,4'-diisocyanato-diphenylmethane, 9% of 2,4'-diisocyanato-diphenylmethane, 1 % of 2,2'-diisocyanatodiphenylmethane and 10% of higher functional homologs of these diisocyanates.
Polyisocyanate IV:
A 70% solution in Solvesso*100 solvent of an isocyanurate group-containing polyisocyanate prepared from IPDI and having an NCO
content of the solution of 11.6%.
Polyisocyanate V:
An isocyanurate group-containing polyisocyanate prepared from 1,6-diisocyanatohexane and having an NCO-content of 21.0%, a monomeric 1,6-diisocyanatohexane content of 0.1 % and a viscosity (23°C) of 3300 mPa.s.
Dihydroxy compound I:
An adduct prepared by adding 2 moles of propylene carbonate *trade-mark Mo3982 onto 1 mole of hydrazine and having the formula I .
Example 1 (Comparative example) Formulation:
195 g (1.0 equiv) polyisocyanate I
176 g (1.1 moles} malonic acid diethyl ester 2.7 g sodium methylate solution (30%) in methanol 160.1 g (70%) methoxypropyl acetate 533.8 g (1.0 equiv) blocked NCO groups Pertormance:
Polyisocyanate I was introduced into a vessel and stirred at room temperature. The distilled malonic ester and sodium methylate solution were stirred together in a glass beaker. This slightly turbid mixture was poured into the stirred polyisocyanate. An exothermic reaction was observed. The reacting mixture was heated to approx. 60°C. Using an oil bath, the temperature was raised to 70°C and the reaction was continued at this temperature for approx. 4 hours until the NCO band had disappeared from the IR spectrum. The reaction product was diluted with the solvent and an almost colorless, clear solution was obtained which had a viscosity of approx. 1000 mPa.s at 23°C.
After storage for approx. 1 week at room temperature, the viscosity of this solution increased dramatically. The solution became gel-like and finally solidified into a glassy, transparent gel after storage for 14 days storage. The product could be reliquefied by melting (approx. 60°C).
Mo3982 Example 2 (comparative example) Formulation:
195 g (1 equiv) polyisocyanate 1 106 g (1.05 moles) diisopropylamine 129 g (70%) methoxypropyl acetate 430 g (1.0 equiv) blocked NCO groups Pertormance:
Polyisocyanate I and solvent were introduced into a vessel.
Diisopropylamine was added dropwise at room temperature while the mixture was being stirred. The mixture was heated to 70°C for approx.
minutes to complete the reaction. No NCO content was detectable by IR
spectrometry. A colorless, clear solution having a viscosity at 23°C of approx. 6000 mPa.s was obtained. Over a period of several days, the solution started to flow in a gel-like manner down the sides of the vessel.
After two weeks, the product began to crystallize out into whitish crystals.
Example 3 (according to the invention) Formulation:
390 g (2.0 equiv) polyisocyanate I
160 g (1.0 mote) malonic acid diethyl ester 2.4 g sodium methylate solution (30%) 111.1 g (1.1 moles) diisopropylamine 284.4 g methoxypropyl acetate 947.9 g (2.0 equiv} blocked NCO groups Performance:
Polyisocyanate I was introduced into a vessel at room temperature and stirred. The mixture of malonic ester and sodium methylate solution was then added. On completion of addition, the temperature had risen to approx. 50°C. The mixture was heated to 70°C and stirred for a further Mo3982 ~~~~r 20 minutes. The measured NCO content was just below the calculated content of 7.6%. The mixture was diluted with methoxypropyl acetate and cooled to approx. 40°C, and diisopropylamine was added dropwise. 10 minutes after completion of the addition, no NCO content was detectable by IR spectrometry. A clear, almost colorless solution was obtained having a viscosity at 23°C of 2500 mPa.s and an NCO content in blocked form of 8.7%. The solution had a storage life of at least 6 months without crystallization.
Example 4 (according to the invention) Formulation:
195.0 g (1.0 equiv)polyisocyanate I
131.0 g (1.0 equiv) polyisocyanate II
75.8 g (0.75 moles) diisopropylamine 104.0 (0.8 moles) acetoacetic ester 2,p g sodium methylate solution (30%) 59.0 g (0.50 equiv) dihydroxy compound I
243.0 g (70%) butyl acetate 809.8 g (1.5 equiv) blocked NCO groups Pertormance:
Both polyisocyanates were introduced into a vessel in butyl acetate.
To the stirred solution was added dropwise the stated quantity of diiso-propylamine, wherein a slight exothermic reaction was observed. Then, the highly viscous, colorless dihydroxy compound I was added and the reaction mixture was heated to 100°C. After a reaction time of approx.
hours, the calculated NCO content of 4.5% was achieved. The mixture was cooled to 70°C and the solution of acetoacetic acid ethyl ester with sodium methylate was added in portions. After a reaction time of approx. 12 hours no NCO content was detectable by IR spectrometry. A clear, light yellow solution was obtained having a viscosity at 23°C of approx. 3000 mPa.s and an NCO
content in Mo3982 blocked form of 7.7%. The solution had a storage life of at least 6 months.
Example 5 (according to the invention) Formulation:
804.0 g (6.0 equiv) polyisocyanate III
336.0 g (3.0 equiv) of a polypropylene glycol with an OH
number of 500 240.0 g (1.5 moles) malonic acid diethyl ester 2.4 g sodium methylate solution (30%) 151.0 g (1.5 moles) diisopropylamine 654.0 g (approx. 30%) methoxypropyl acetate 2187.4 g (3.0 equiv) blocked NCO groups Performance:
Polyisocyanate III, solvent and polypropylene glycol (OH number 500) were introduced into a vessel and heated to 100°C while being stirred. After a reaction time of approx. 30 minutes, the calculated NCO
content of 7.0% was reached. The mixture was cooled to 70°C and the solution of malonic ester and sodium methylate was added in portions.
The mixture was stirred for approx. 1 hour at 70°C and the NCO
content was found to be slightly less than the calculated value of 3.09%.
Diisopropylamine was then added dropwise over 50 minutes without further heating. A sample shows no NCO content was detectable by IR
spectrometry. A reddish-brown, clear solution was obtained having a viscosity at 23°C of 6000 mPa.s. The blocked polyisocyanate solution had a storage life of at least 6 months without crystallization. The blocked NCO group content was 5.7%.
Mo3982 Example 6 (according to the invention) Formulation:
724 g (2.0 equiv) polyisocyanate IV
69 g (1.0 mole) 1,2,4-triazole 106 g (1.05 moles) diisopropylamine 343 g (55%) methoxypropyl acetate 1242 g (2.0 equiv) blocked NCO groups Performance:
Polyisocyanate IV was introduced into a vessel and mixed with the crystalline 1,2,4-triazole. The mixture was heated to 110°C while being stirred and reacted for approx. 3 hours until the calculated NCO content of 5.29% was reached. The mixture was then diluted with methoxypropyl acetate and cooled. At approx. 50°C, the diisopropylamine was added dropwise to the solution. A slight exothermic reaction was observed. On completion of diisopropylamine addition, no NCO content was detectable by IR spectrometry. The 55% solution of this blocked polyisocyanate had a viscosity at 23°C of 2300 mPa.s and an NCO content in blocked form of 6.76%. The solution had a storage life of at least 6 months without crystallization.
Example 7 (according to the invention) Formulation:
280.0 g (1.4 equiv) polyisocyanate V
362.0 g (1.0 equiv) polyisocyanate IV
69.0 g (1.0 mole) 1,2,4-triazole 101.0 g (1.0 mole) diisopropylamine 47.2 g (0.4 equiv) diol I
302.0 g (65%) methoxypropyl acetate 1161.2 g (2.0 equiv) blocked NCO groups Mo3982 Performance:
Both polyisocyanate components, the methoxypropyl acetate and the crystalline 1,2,4-triazole (flakes) were introduced into a vessel and heated to 100°C while being stirred. After approx. 30 minutes, the NCO
content of the reaction mixture had fallen to the calculated value of 4.1 %.
The mixture was cooled to 60°C, diisopropylamine was added dropwise and diol I added. The mixture was then reacted for approx. 2 hours at 100°C until no further NCO groups were detectable by IR spectroscopy.
A clear, light yellow solution of a co-blocked polyisocyanate was obtained. The solution had a storage life of at least 6 months without crystallization. The viscosity at 23°C was approx. 7800 mPa.s.
Example 8 (according to the invention) Formulation:
362.0 g (1.0 equiv) polyisocyanate IV
280.0 g (1.4 equiv) polyisocyanate V
156.0 g (1.2 moles) acetoacetic ester 1.2 g sodium methylate solution (30%) 121.2 g (1.2 moles) diisopropylamine 155.0 g methoxypropyl acetate 1055.4 (1.4 equiv) blocked NCO groups Performance:
The isocyanate mixture was blocked in a manner analogous to that described in Example 4. A clear, light yellow solution (75%) was obtained having a viscosity at 23°C of approx. 14,500 mPa.s and an NCO group content in blocked form of 9.3%. The solution had a storage life of at least 6 months without crystallization.
Mo3982 w 211035 Example 9 - Ready-to-spray, pigmented baking filler (according to the invention) 71.3 parts by weight of a polyester solution (I) present at 65%
solids in a mixture of Solvesso*100 solvent/isobutanol (weight ratio 31.5:3.5), having a hydroxyl content, based on solution, of 1.7%, an acid value of 5 and a viscosity of 2700 mPa.s at 23°C (Alkynol*1665, manufacturer: Bayer, Leverkusen) were combined with 216.4 parts by weight of barium sulphate (Blanc fixe micro* manufacturer. Sachtleben-Chemie, Duisberg), 54.1 parts by weight of titanium dioxide (Bayertitan*
R-KB-2, manufacturer: Bayer, Leverkusen), 18.0 parts by weight of a pigment (light blue 2 R, manufacturer: Bayer, Leverkusen), 3.6 parts by weight of a dispersing auxiliary (Antiterra U, present as a 50% solution, manufacturer: Byk-Chemie, Wesel), 3.6 parts by weight of silica gel (Aerosil*R 972, manufacturer: Degussa, Frankfurt am Main), 16.0 parts by weight of 1-methoxypropyl acetate-2, 15.9 parts by weight of butyl acetate and 15.9 carts by weight of xylene. The mixture was dispersed for 45 minutes in a bead mill (model: VSME, manufacturer: Vollrath, Cologne) such that the temperature of the material being dispersed did not exceed 50°C.
The resulting paste was combined by stirring with a further 171.7 parts by weight of polyester solution I, 80.5 parts by weight of a polyester solution (II) present at 80% solids in butyl acetate and having a hydroxyl content of 3.4%, an acid value of <_ 2 and a viscosity of 2500 to 3500 mPa.s at 23°C (Desmophen*670, 80%, manufacturer: Bayer, Leverkusen), 3.6 parts by weight of a flow control auxiliary (Byk*358, present as a 50% solution, manufacturer: Byk Chemie, Wesel), 81.4 parts by weight of an amino resin (Maprenai*MF 890, 62% in n-butanol, manufacturer: Cassella, Frankfurt am Main), 117.1 parts by weight of the *trade-mark Mo3982 _17_ polyisocyanate solution of Example 8, 43.6 parts by weight of 1-methoxypropyl acetate-2, 43.6 parts by weight of butyl acetate and 43.7 parts by weight of xylene.
The resulting coating composition was readily sprayable and displayed good flow-out on heat-resistant polyester film, glass, sheet iron and electrocoated sheet metal.
Solids content according to weighed portion: 65.6%.
Viscosity as draining time: 30 seconds in 4 mm DIN cup (DIN 53 211).
The coating composition was sufficiently reactive at a baking temperature of 130°C to cure without catalysis. Properties of the coating after baking for 30 minutes in a circulating air drying cabinet at 130°C:
Konig pendulum hardness: 142 sec (DIN 53 157) Erichsen indentation to DIN 53 156: 10.5 mm Dry film thicknesses of up to 45 Nm were achieved in a single operation without blistering or surface defects on electrocuted metal sheets (cathodically electrocuted metal sheet, lacquer test sheets from Mercedes Benz AG, Sindelfingen).
Within the coating structure, the filler exhibited good adhesion to the substrate (electrocoating) and good intercoat adhesion to basecoat and topcoat lacquers.
Stone impact testing:
A cathodically dipcoated t metal sheet was coated with the filler produced according to the invention (dry film thickness 35 Nm, baked for minutes at 130°C), overcoated with a commercial alkydlamino based 25 topcoat (Tornado*red, PPG, Wuppertal) and baked for 25 minutes at 155°C (dry film thickness 45 Nm). The coating displayed high resistance to stone impact when subjected to the VDA (Verband der Automobilindustrie = automotive industry association) stone impact test *trade-mark Mo3982 _18- 2~:~~~ ~~
(model 508, 2 times 500 g steel pellets, 1.5 bar), having a rating of 1 or 2 according to the prescribed VDA assessment method.
Storage stability:
After 3 months' storage at room temperature, the viscosity of the coating composition was unchanged.
After storage for 30 days in a drying cabinet at 50°C, the viscosity to DIN 53 211 (see above) had risen to a draining time of 42 seconds from a 4 mm DIN cup. The Konig pendulum hardness (see above) after baking in an circulating air drying cabinet (30 minutes at 130°C) was sec.
Example 10 (comparative example) Formulation:
362.0 g (1.0 equiv) poiyisocyanate IV
280.0 g (1.4 equiv) polyisocyanate V
156.0 g (1.2 moles) acetoacetic ester 192.0 g (1.2 moles) malonic acid diethyl ester 3.2 g sodium methylate solution (30%) 180.0 g methoxypropyl acetate 1173.2 g (2.4 equiv) blocked NCO groups Performance:
The polyisocyanates were combined while being stirred at room temperature with the mixture of the two CH-acidic esters and sodium methylate. Addition was made in portions, so that the exothermic reaction was controlled. On completion of the addition, the temperature of the reaction mixture had risen to approx. 60°C. The reaction was continued for a further 5 hours at 70°C, until the NCO band in the IR spectrum was scarcely detectable. The mixture was then diluted with methoxypropyl acetate. A clear, light yellow solution (approx. 75%) was obtained having Mo3982 -19- ~ 2 1 1 0 2 3 5 a viscosity at 23°C of approx. 10,000 mPa.s and an NCO group content in blocked form of 8.5°~.
Examele 11 - Comparison Example Comparison of increase in viscosity in clear lacquers a) According to the invention 503.6 parts by weight of polyester solution ( from Example 9 were combined with 226.4 parts by weight of the polyisocyanate solution from Example 8, 1.8 parts by weight of a flow control auxiliary (Byk*358), 178.8 parts by weight of 1-methoxypropyl acetate-2 and 89.4 parts by weight of xylene and homogenized by stirring.
(Blocked) NCO/OH ratio = 1Ø
Solids content according to weighed portion: approx. 49.8%
Viscosity as draining time: 30 sec (DIN 53 211).
b) Comparison Example 11 a) was repeated with the sole exception that the polyisocyanate Solution of Example 8 was substituted by the equivalent quantity of the polyisocyanate solution according to Example 10.
(Blocked) NCO/OH ratio = 1Ø
Solids content according to weighed portion: approx. 55.7%
Viscosity as draining time: 30 sec (DIN 53 211).
Storage at 50°C:
After storage for 14 days in a circulating air drying cabinet at 50°C, the viscosity (measured as draining time, see above) of coating composition 11 a) was 36 sec; after 30 days the draining time had not increased further. However, Coating composition 11 b) had a draining time of 60 sec after only 14 days.
Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is *trade-mark Mo3982 -20- 2~.1~23~
solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims.
Mo3982
Claims (11)
1. An organic polyisocyanate which has a content of unblocked and blocked isocyanate groups (calculated as NCO) of 5 to 20 wt.%, wherein at least 95% of the isocyanate groups are present in blocked form and wherein the blocking agent consists essentially of A) 30 to 70 equivalent % of diisopropylamine, B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B), wherein the percentages of A), B) and C) add up to 100.
2. The organic polyisocyanate of Claim 1 wherein 100% of the isocyanate groups are present in blocked form.
3. The organic polyisocyanate of Claim 1 wherein the blocking agent consists essentially of A) 30 to 70 equivalent % of diisopropylamine and B) 30 to 70 equivalent-% of malonic acid diethyl ester.
4. The organic polyisocyanate of Claim 2 wherein the blocking agent comprises A) 30 to 70 equivalent-% of diisopropylamine and B) 30 to 70 equivalent-% of malonic acid diethyl ester.
5. The organic polyisocyanate of Claim 1 wherein said organic polyisocyanate is based on 1,6-diisocyanatohexane.
6. The organic polyisocyanate of Claim 2 wherein said organic polyisocyanate is based on 1,6-diisocyanatohexane.
7. The organic polyisocyanate of Claim 3 wherein said organic polyisocyanate is based on 1,6-diisocyanatohexane.
8. The organic polyisocyanate of Claim 4 wherein said organic polyisocyanate is based on 1,6-diisocyanatohexane.
9. The organic polyisocyanate of Claim 1 wherein said organic polyisocyanate is present in the form of a 50 to 80 wt.% solution in one or more organic solvents.
10. A process for the production of an organic polyisocyanate which comprises reacting at 20 to 120°C at least 95 equivalent-% of the isocyanate groups of an organic polyisocyanate with a blocking agent mixture containing, based on the total equivalents of blocking agents, A) 30 to 70 equivalent-% of diisopropylamine, B) 30 to 70 equivalent-% of at least one other blocking agent selected from CH-acidic esters and 1,2,4-triazole and C) 0 to 20 equivalent-% of blocking agents other than those set forth in A) and B).
11. A coating composition containing the organic polyisocyanate of Claim 1 and an organic polyhydroxyl compound.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4240480A DE4240480A1 (en) | 1992-12-02 | 1992-12-02 | Organic polyisocyanates with at least partially blocked isocyanate groups |
| DEP4240480.0 | 1992-12-02 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2110235A1 CA2110235A1 (en) | 1994-06-03 |
| CA2110235C true CA2110235C (en) | 2003-02-25 |
Family
ID=6474179
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002110235A Expired - Fee Related CA2110235C (en) | 1992-12-02 | 1993-11-29 | At least partially blocked organic polyisocyanates, a process for their preparation and their use in coating compositions |
Country Status (13)
| Country | Link |
|---|---|
| US (1) | US5350825A (en) |
| EP (1) | EP0600314B1 (en) |
| JP (1) | JP3189997B2 (en) |
| KR (1) | KR100292134B1 (en) |
| AT (1) | ATE143393T1 (en) |
| BR (1) | BR9304906A (en) |
| CA (1) | CA2110235C (en) |
| CZ (1) | CZ287133B6 (en) |
| DE (2) | DE4240480A1 (en) |
| ES (1) | ES2092207T3 (en) |
| FI (1) | FI103579B (en) |
| MX (1) | MX9307189A (en) |
| PL (1) | PL172821B1 (en) |
Families Citing this family (38)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4416750A1 (en) * | 1994-05-13 | 1995-11-16 | Bayer Ag | Mixed blocked polyisocyanates |
| DE19516400A1 (en) * | 1995-05-04 | 1996-11-07 | Bayer Ag | Blocked polyisocyanates and their use |
| US6730150B1 (en) * | 1996-06-28 | 2004-05-04 | Xerox Corporation | Phase change ink formulation containing a combination of a urethane resin, a mixed urethane/urearesin, a mono-amide and a polyethylene wax |
| DE19738497A1 (en) * | 1997-09-03 | 1999-03-04 | Bayer Ag | Amine-blocked polyisocyanates |
| DE19813352A1 (en) * | 1998-03-26 | 1999-09-30 | Bayer Ag | Malonic ester-blocked polyisocyanates with formaldehyde against thermal yellowing |
| FR2781804B1 (en) * | 1998-07-29 | 2000-11-03 | Rhodia Chimie Sa | (POLY) ISOCYANATES MIXED MASKS |
| FR2784113B1 (en) * | 1998-10-02 | 2002-06-07 | Rhodia Chimie Sa | MODIFIED ISOCYANATES |
| US6559264B1 (en) | 1998-12-07 | 2003-05-06 | Bayer Aktiengesellschaft | Malonic acid ester/triazole mixed blocked HDI trimer/formaldehyde stabilization |
| JP4614036B2 (en) * | 2001-08-31 | 2011-01-19 | Ｄｉｃ株式会社 | Leather-like manufacturing method |
| DE10156897A1 (en) * | 2001-11-20 | 2003-05-28 | Bayer Ag | A blocked isocyanate mixture containing epsilon-caprolactam blocking agent, diisopropylamine, and 1,2,4-triazole useful for coil coating and for coating wood, metals, glass, ceramics, and plastics |
| DE10160570A1 (en) * | 2001-12-10 | 2003-06-18 | Bayer Ag | A single component PUR binder containing cycloaliphatic polyisocyanate enamel, isocyanate group blocking agent, polymeric OH component useful for production of stoving enamels by coil coating processes |
| EP1359202A1 (en) | 2002-05-03 | 2003-11-05 | Sika Schweiz AG | Temperature curable epoxy resin composition |
| DE10226925A1 (en) * | 2002-06-17 | 2003-12-24 | Bayer Ag | Blocked polyisocyanates |
| DE10253482A1 (en) * | 2002-11-18 | 2004-06-03 | Bayer Ag | Solidified stable blocked polyisocyanates |
| EP1431325A1 (en) | 2002-12-17 | 2004-06-23 | Sika Technology AG | Heat-curable epoxy resin composition with improved low-temperatur impact strength |
| DE10260298A1 (en) * | 2002-12-20 | 2004-07-01 | Bayer Ag | Hydrophilized blocked polysocyanates |
| EP1498441A1 (en) | 2003-07-16 | 2005-01-19 | Sika Technology AG | Temperature curable compositions with low temperature impact strength modifier |
| US7772307B2 (en) * | 2003-08-27 | 2010-08-10 | Great Eastern Resins Industrial Co., Ltd. | Water dispersible polyisocyanate composition and its uses |
| DE10348380A1 (en) * | 2003-10-17 | 2005-06-02 | Bayer Materialscience Ag | Polyisocyanates with biuret structure blocked with secondary amines |
| US20060089480A1 (en) * | 2004-10-21 | 2006-04-27 | Roesler Richard R | Biuretized isocyanates and blocked biuretized isocyanates |
| US20060089481A1 (en) * | 2004-10-21 | 2006-04-27 | Roesler Richard R | Blocked biuretized isocyanates |
| EP1741734A1 (en) | 2005-07-05 | 2007-01-10 | Sika Technology AG | Heat curable epoxy resin composition having low temperature impact strength comprising solid epoxy resins |
| EP1876194A1 (en) * | 2006-06-30 | 2008-01-09 | Sika Technology AG | Heat curing composition usable as an adhesive for coated substrates |
| EP1916269A1 (en) * | 2006-10-24 | 2008-04-30 | Sika Technology AG | Blocked polyurethane prepolymers and heat curing epoxy resin compositions |
| EP2085426B1 (en) * | 2008-01-30 | 2010-10-13 | Sika Technology AG | Wash-resistant thermo hardening epoxy resin adhesives |
| JP5775660B2 (en) * | 2009-06-03 | 2015-09-09 | 旭化成ケミカルズ株式会社 | High elongation, low temperature curable block polyisocyanate composition |
| BR112012019717A2 (en) * | 2010-02-08 | 2023-11-21 | Asahi Kasei Chemicals Corp | BLOCKED POLYISOCYANATE COMPOSITION, COATING COMPOSITION, COATING FILM, AND, METHOD FOR PRODUCING A BLOCKED POLYISOCYANATE COMPOSITION |
| JP5572567B2 (en) * | 2010-02-08 | 2014-08-13 | 旭化成ケミカルズ株式会社 | Method for producing a block polyisocyanate composition |
| JP5572565B2 (en) * | 2010-02-08 | 2014-08-13 | 旭化成ケミカルズ株式会社 | Method for producing a block polyisocyanate composition |
| JP5572566B2 (en) * | 2010-02-08 | 2014-08-13 | 旭化成ケミカルズ株式会社 | Block polyisocyanate composition and coating composition containing the same |
| JP5562267B2 (en) * | 2010-02-08 | 2014-07-30 | 旭化成ケミカルズ株式会社 | Block polyisocyanate composition and coating composition containing the same |
| JP5562271B2 (en) * | 2010-06-04 | 2014-07-30 | 旭化成ケミカルズ株式会社 | Method for producing block polyisocyanate composition |
| JP5777351B2 (en) * | 2010-06-07 | 2015-09-09 | 旭化成ケミカルズ株式会社 | Method for producing coating composition |
| US11091584B2 (en) | 2015-07-31 | 2021-08-17 | Covestro Deutschland Ag | Blocked polyisocyanate composition based on pentamethylene 1,5-diisocyanate |
| EP3556789A1 (en) | 2018-04-16 | 2019-10-23 | Evonik Degussa GmbH | Hydrophilic crosslinkers containing alkoxysilane groups |
| CN109627422B (en) * | 2018-11-19 | 2021-04-20 | 万华化学集团股份有限公司 | Preparation method of butanone oxime closed polyisocyanate |
| EP4282894A1 (en) | 2022-05-25 | 2023-11-29 | Covestro Deutschland AG | Single-component stoving system |
| EP4282893A1 (en) | 2022-05-25 | 2023-11-29 | Covestro Deutschland AG | Blocked polyisocyanates |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2436872C3 (en) * | 1974-07-31 | 1980-04-10 | Basf Ag, 6700 Ludwigshafen | 1 - (Bis-ethoxycarbonyl) -acetylamino-S-bis-ethoxycarbonyO-acetyl-aminomethyl-333-trimethyl-cyclohexane |
| DE2812252A1 (en) * | 1978-03-21 | 1979-10-04 | Bayer Ag | 1,2,4-TRIAZOLE-BLOCKED POLYISOCYANATE AS CROSS-LINKING AGENTS FOR PAINT BINDERS |
| DE3001060A1 (en) * | 1980-01-12 | 1981-07-16 | Chemische Werke Hüls AG, 4370 Marl | Poly isocyanato-isocyanurate blocked by malonic acid ester - or acetoacetic acid ester, used as hardener for thermoplast, esp. in one-component lacquer |
| US4495229A (en) * | 1982-06-08 | 1985-01-22 | Chemische Werke Huls A.G. | One-component, heat-curing polyurethane-coatings, stable in storage |
| DE3221558A1 (en) * | 1982-06-08 | 1983-12-08 | Chemische Werke Hüls AG, 4370 Marl | STORAGE POLYURETHANE COMPONENT BURNING VARNISHES |
| DE3311516A1 (en) * | 1983-03-30 | 1984-10-04 | Basf Farben + Fasern Ag, 2000 Hamburg | HEAT-CURABLE COATING AGENTS AND THEIR USE |
| JPH0676567B2 (en) * | 1986-06-16 | 1994-09-28 | 関西ペイント株式会社 | Resin composition for cationic electrodeposition coating |
| GB8913859D0 (en) * | 1989-06-16 | 1989-08-02 | Hunter Douglas Ind Bv | Blocked isocyanates and their production and use |
-
1992
- 1992-12-02 DE DE4240480A patent/DE4240480A1/en not_active Withdrawn
-
1993
- 1993-11-17 MX MX9307189A patent/MX9307189A/en unknown
- 1993-11-18 AT AT93118592T patent/ATE143393T1/en not_active IP Right Cessation
- 1993-11-18 EP EP93118592A patent/EP0600314B1/en not_active Expired - Lifetime
- 1993-11-18 DE DE59303960T patent/DE59303960D1/en not_active Expired - Lifetime
- 1993-11-18 ES ES93118592T patent/ES2092207T3/en not_active Expired - Lifetime
- 1993-11-23 US US08/157,350 patent/US5350825A/en not_active Expired - Lifetime
- 1993-11-29 CA CA002110235A patent/CA2110235C/en not_active Expired - Fee Related
- 1993-11-30 PL PL93301254A patent/PL172821B1/en not_active IP Right Cessation
- 1993-11-30 FI FI935357A patent/FI103579B/en active
- 1993-12-01 KR KR1019930026023A patent/KR100292134B1/en not_active IP Right Cessation
- 1993-12-01 JP JP32573993A patent/JP3189997B2/en not_active Expired - Fee Related
- 1993-12-01 BR BR9304906A patent/BR9304906A/en not_active IP Right Cessation
- 1993-12-02 CZ CZ19932620A patent/CZ287133B6/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| MX9307189A (en) | 1994-08-31 |
| ES2092207T3 (en) | 1996-11-16 |
| FI935357A (en) | 1994-06-03 |
| KR100292134B1 (en) | 2001-09-17 |
| KR940014490A (en) | 1994-07-18 |
| DE59303960D1 (en) | 1996-10-31 |
| FI103579B1 (en) | 1999-07-30 |
| CZ262093A3 (en) | 1994-06-15 |
| BR9304906A (en) | 1994-07-26 |
| ATE143393T1 (en) | 1996-10-15 |
| EP0600314A1 (en) | 1994-06-08 |
| CZ287133B6 (en) | 2000-09-13 |
| CA2110235A1 (en) | 1994-06-03 |
| DE4240480A1 (en) | 1994-08-25 |
| EP0600314B1 (en) | 1996-09-25 |
| PL301254A1 (en) | 1994-06-13 |
| JP3189997B2 (en) | 2001-07-16 |
| US5350825A (en) | 1994-09-27 |
| FI935357A0 (en) | 1993-11-30 |
| JPH06211771A (en) | 1994-08-02 |
| FI103579B (en) | 1999-07-30 |
| PL172821B1 (en) | 1997-11-28 |
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| EEER | Examination request | ||
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