AU716848B2

AU716848B2 - Curable compositions for coatings

Info

Publication number: AU716848B2
Application number: AU68049/96A
Authority: AU
Inventors: Brian D. Bammel; Paul J Harris; John D. Mcgee; Gregory G Menovcik; Walter H Ohrbom; John W Rehfuss; Todd A Seaver
Original assignee: BASF Corp
Current assignee: BASF Corp
Priority date: 1995-10-06
Filing date: 1996-10-04
Publication date: 2000-03-09
Anticipated expiration: 2016-10-04
Also published as: KR970021229A; JPH09169839A; KR100432946B1; BR9605019A; AU6804996A; CN1150946A

Description

A

-1- P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990

SUBSTITUTE

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: CURABLE COMPOSITIONS FOR COATINGS a a a .f a.f ft f ft f o oo oo a a o ooo ft ft ft*f tf ft ft ft fttftf ft f ft t f ft ft f ft ft ft tf f The following statement is a full description of this invention, including the best method of performing it known to us: GH REF: P19343-BR:DAA:RK 1A- CURABLE COMPOSITIONS FOR COATINGS Field of the Invention This invention relates to methods of preparing carbamate- or urea-functional compounds and to their use in curable coating compositions, particularly to curable compositions utilizing a carbamate- or urea-functional compound as one of the components of the composition.

Background of the Invention Curable coating compositions such as thermoset coatings are widely used in the coatings art.

Carbamate- or urea-functional compositions have been described for uses such as curable compositions, particularly curable coating compositions. They are 15 often used for topcoats in the automotive and industrial coatings industry. Color-plus-clear composite coatings are particularly useful as topcoats where exceptional gloss, depth of color, distinctness of image, or special metallic effects are desired. The 20 automotive industry has made extensive use of these coatings for automotive body panels. Color-plus-clear composite coatings, however, require an extremely high S: degree of clarity in the clearcoat to achieve the desired visual effect. High-gloss coatings also require a low degree of visual aberrations at the surface of the coating in order to achieve the desired visual effect such as high distinctness of image (DOI).

-2- Such coatings are especially susceptible to a phenomenon known as environmental etch. Environmental etch manifests itself as spots or marks on or in the finish of the coating that often cannot be rubbed out.

Curable coating compositions based on curable components having carbamate or urea functionality have been proposed have been described in the art to provide etch-resistant coatings, U.S. Patent 5,356,669 and WO 94/10211.

In addition to resistance to environmental etch, a number of other characteristics can be desirable. For example, it may be desirable to provide a coating having a high degree of flexibility. This can be particularly •advantageous if the substrate on which the coating is placed is itself flexible, as in the case of plastic, ••leather, or textile substrates.

a a S.It is also desirable to reduce the amount of solvent required in coating compositions in order to reduce the volatile organic content (VOC), which is better for the oe 20 environment.

ooe.

Finally, it is desirable to provide a variety of S"carbamate- or urea-functional materials to provide coatings with a good combination of properties such as adurability, hardness, and resistance to scratching, 25 marring, solvents, and acids.

Summary of the Invention According to the first aspect of the present invention, there is provided a method of preparing carbamate- or urea-functional compounds capable of providing one or more of the above-described properties.

This method comprises a method of making a carbamate- or Surea-functional compound having at least one ester or Q '\-amide group comprising the step of reacting a lactone or -2ahydroxy carboxylic acid with a compound comprising a carbamate or urea group or a group that can be converted to a carbamate or urea group, and an active hydrogen group capable of reacting with the hydroxy ooo* i oo o *oo *o oo *o* o* o *oo oo*oo* 29526 i 3 carboxylic acid or in a ring-opening reaction with a lactone.

Compounds prepared according to the present invention can provide coatings having a good combination of properties such as durability, hardness, and resistance to scratching, marring, solvents, and acids. Such coating compositions can also provide low VOC levels, and can be used to prepare coatings having good flexibility for use over flexible substrates.

From a second aspect the present invention provides a coating composition comprising a compound comprising a plurality of functional crosslinking groups, at least one of which is a carbamate or urea functional group, which compound also includes at least one ester or amide group derived from a reaction of an active hydrogen group with a lactone ring or a hydroxy carboxylic acid, and a curing agent comprising a plurality of groups that are reactive with the functional groups on 20 compound The present invention provides coatings having a good combination of properties such as durability, hardness, and resistance to scratching, marring, solvents, and acids. Coating compositions according to the invention can also provide low VOC levels, and can be used to prepare coatings having good flexibility for use over flexible substrates.

Description of the Preferred Embodiments According to the present invention, compound *o 30 has carbamate or urea functionality, and may be formed in a number of ways. In one embodiment, the o: compound is formed by reaction of a compound having at least one carbamate or urea group (or a group that can be converted to carbamate or urea) and an active hydrogen group with a lactone or hydroxy carboxylic acid Carbamate groups can generally be 4 characterized by the formula 0

IIN

-0---C-NHR wherein R is H or alkyl, preferably of 1 to 4 carbon atoms. Preferably, R is H or methyl, and more preferably R is H. Urea groups can generally be characterized by the formula 0

II

NR '-C--NHR" wherein R' and R" each independently represents H or alkyl, preferably of 1 to 4 carbon atoms, or R' and R" may together form a heterocyclic ring structure where R' and R" form an ethylene bridge).

The compound can be formed by reacting a lactone or hydroxy carboxylic acid with a compound having an active hydrogen group capable of ring-opening a lactone hydroxyl, primary amine, acid) or undergoing a condensation reaction with a hydroxy carboxylic acid and a carbamate or urea group or a group that can be converted to carbamate or urea.

When a compound having an active hydrogen group and a group that can be converted to carbamate or urea is used to react with the lactone or hydroxy carboxylic acid, conversion of the group to a carbamate or urea can be accomplished during or after such reaction.

•and Compounds having a carbamate or urea group and an active hydrogen group are known in the art.

Hydroxypropyl carbamate and hydroxyethyl ethylene urea, for example, are well known and commercially available.

Amino carbamates are described in U.S. Patent 2,842,523. Hydroxyl ureas may also be prepared by reacting an oxazolidone with ammonia or a primary amine or by reacting ethylene oxide with ammonia to form an amino alcohol and then reacting the amine group of that compound or any other amino alcohol with hydrochloric acid, then urea to form a hydroxy urea. Amino ureas can

P

5 be prepared, for example, by reacting a ketone with a diamine having one amine group protected from reaction by steric hindrance), followed by reaction with HNCO the product of the thermal decomposition of urea), and then water. Alternatively, these compounds can be prepared by starting with a compound having an active hydrogen and a group that can be converted to carbamate or urea as described below, and then converting that group to the carbamate or urea prior to reaction with the lactone or hydroxy carboxylic acid.

Groups that can be converted to carbamate include cyclic carbonate groups, epoxy groups, and unsaturated bonds. Cyclic carbonate groups can be converted to carbamate groups by reaction with ammonia or a primary amine, which ring-opens the cyclic carbonate to form a P-hydroxy carbamate. Epoxy groups can be converted to carbamate groups by first converting to a cyclic carbonate group by reaction with

CO

2 This can be done at any pressure from atmospheric 20 up to supercritical CO 2 pressures, but is preferably under elevated pressure 60-150 psi). The temperature for this reaction is preferably 60-150 0

C.

Useful catalysts include any that activate an oxirane ring, such as tertiary amine or quaternary salts tetramethyl ammonium bromide), combinations of complex organotin halides and alkyl phosphonium halides

(CH

3 3 SnI, Bu 4 SnI, Bu 4 PI, and (CH 3 4 PI, potassium salts

K

2

CO

3 KI) preferably in combination with crown Sethers, tin octoate, calcium octoate, and the like.

30 The cyclic carbonate group can then be converted to a carbamate group as described above. Any unsaturated S: bond can be converted to carbamate groups by first reacting with peroxide to convert to an epoxy group, then with CO 2 to form a cyclic carbonate, and then with ammonia or a primary amine to form the carbamate.

Other groups, such as hydroxyl groups or isocyanate groups can also be converted to carbamate or 6 urea groups to form the compound However, if such groups were to be present on the compound and then converted to carbamate after the reaction with the lactone or hydroxy carboxylic acid, they would.have to be blocked so that they would not react with the lactone, the hydroxy carboxylic acid, or with other active hydrogen groups. When blocking these groups is not feasible, the conversion to carbamate or urea would have to be completed prior to reaction with the lactone or hydroxy carboxylic acid. Hydroxyl groups can be converted to carbamate groups by reaction with a monoisocyanate methyl isocyanate) to form a secondary carbamate group or with cyanic acid (which may be formed in situ by thermal decomposition of urea) to form a primary carbamate group unsubstituted carbamates). This reaction preferably occurs in the presence of a catalyst as is known in the art. A hydroxyl group can also be reacted with phosgene and then ammonia to form a compound having primary •20 carbamate group(s) or by reaction of a hydroxyl with phosgene and then a primary amine to form a compound having secondary carbamate groups. Another approach is to react an isocyanate with a compound such as hydroxyalkyl carbamate to form a carbamate-capped isocyanate derivative. For example, one isocyanate group on toluene diisocyanate can be reacted with :::hydroxypropyl carbamate, followed by reaction of the S, other isocyanate group with an excess of polyol to form a hydroxy carbamate. Finally, carbamates can be 30 prepared by a transesterification approach where hydroxyl group reacted with an alkyl carbamate methyl carbamate, ethyl carbamate, butyl carbamate) to form a primary carbamate group-containing compound.

This reaction is performed under heat, preferably in the presence of a catalyst such as an organometallic catalyst dibutyltin dilaurate). Other techniques for preparing carbamates are also known in 7 the art and are described, for example, in P. Adams F. Baron, "Esters of Carbamic Acid", Chemical Review, v. 65, 1965.

Groups such as oxazolidone can also be converted to urea after reaction with the lactone or hydroxy carboxylic acid. For example, hydroxyethyl oxazolidone can be used to initiate the reaction withthe lactone or hydroxy carboxylic acid, followed by reaction of ammonia or a primary amine with the oxazolidone to generate the urea functional group.

Other groups, such as amino groups or isocyanate groups can also be converted to urea groups to form a compound However, if such groups were to be present on the compound and then converted to urea after reaction with the lactone or hydroxy carboxylic acid, they would have to be blocked so that they would not react with the lactone, the hydroxy carboxylic acid, or with the other hydrogen groups present. When blocking these groups is not 20 feasible, the conversion to carbamate or urea would have to be completed prior to reaction with the lactone or hydroxy carboxylic acid. Amino groups can be converted to urea groups by reaction with a monoisocyanate methyl isocyanate) to form a secondary urea group or with cyanic acid (which may be formed in situ by thermal decomposition of urea) to form a primary urea group. This reaction preferably occurs in the presence of a catalyst as is known in the art. An amino group can also be reacted with phosgene 30 and then ammonia to form a compound having primary urea group(s), or by reaction of an amino group with phosgene and then a primary amine to form a compound having secondary urea groups. Another approach is to react an isocyanate with a hydroxy urea compound to form a urea-capped isocyanate derivative. For example, one isocyanate group on toluene diisocyanate can be reacted with hydroxyethyl ethylene urea, followed by t 8 reaction of the other isocyanate group with an excess of polyol to form a hydroxy carbamate.

One preferred class of compounds having an active hydrogen group and a group that can be converted to carbamate is the hydroxyalkyl cyclic carbonates.

Hydroxyalkyl cyclic carbonates can be prepared by a number of approaches. Certain hydroxyalkyl cyclic carbonates like 3-hydroxypropyl carbonate glycerine carbonate) are commercially available.

Cyclic carbonate compounds can be synthesized by any of several different approaches. One approach involves reacting an epoxy group-containing compound with CO 2 under conditions and with catalysts as described hereinabove. Useful catalysts include any that activate an oxirane ring, such as tertiary amine quaternary salts tetramethyl ammonium bromide), tin and/or phosphorus complex salts (CH 3 3 SnI,

(CH

3 4 PI). Epoxides can also be reacted with butyrolactone in the presence of such catalysts. In 20 another approach, a glycol like glycerine is reacted at temperatures of at least 80 0 C. with diethyl carbonate in the presence of a catalyst potassium carbonate) to form a hydroxyalkyl carbonate.

Alternatively, a functional compound containing a ketal of a 1,2-diol having the structure: 0 0

R

30 can be ring-opened with water, for example at temperatures of 60 0 C. or more, preferably with a trace amount of acid, to form a 1,2-glycol, which is then further reacted with diethyl carbonate to form the cyclic carbonate.

Cyclic carbonates typically have 5-6-membered 9 rings, as is known in the art. Five-membered rings are preferred, due to their ease of synthesis and greater degree of commercial availability. Six-membered rings can be synthesized by reacting phosgene with 1,3propane diol under conditions known in the art for the formation of cyclic carbonates. Preferred hydroxyalkyl cyclic carbonates used in the practice can be represented by the formula: 0 0 0 (R)n where R (or each instance of R if n is more than 1) is a hydroxyalkyl group of 1-18 carbon atoms, preferably 1-6 carbon atoms, and more preferably 1-3 carbon atoms, which may be linear or branched and may have substituents in addition to the hydroxyl (which itself may be primary, secondary, or tertiary), and n is 1 or 20 2, which may be substituted by one or more other substituents such as blocked amines or unsaturated groups. More preferably, R is -CmH 2 mOH where the hydroxyl may be primary or secondary and m is 1 to 8, and even more preferably, R is -(CH 2 )p-OH where the 25 hydroxyl is primary and p is 1 to 2.

0o* Lactones that can be ring opened by an active hydrogen are well-known in the art. They include, for example, e-caprolactone, y-caprolactone, 3butyrolactone, P-propriolactone, y-butyrolactone, a- 30 methyl-7-butyrolactone, S-methyl-y-butyrolactone, 7valerolactone, 6-valerolactone, y-nonanoic lactone, yoctanoic lactone, and pentolactone. In one preferred embodiment, the lactone is e-caprolactone. Lactones useful in the practice of the invention can also be characterized by the formula: 10 R O wherein n is a positive integer of 1 to 7 and R is one or more H atoms, or substituted or unsubstituted alkyl groups of 1-7 carbon atoms.

The lactone ring-opening reaction is typically conducted under elevated temperature 80-150 0 The reactants are usually liquids so a solvent is not necessary. However, a solvent may be useful in promoting good conditions for the reaction even if the reactants are liquid. Any non-reactive solvent may be used, including both polar and nonpolar organic solvents. Examples of useful solvents include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and the like. A catalyst is preferably present. Useful catalysts include proton acids octanoic acid, Amberlyst® 15 (Rohm Haas)), tin 00 0* catalysts stannous octoate). Alternatively, the 20 reaction can be initiated by forming a sodium salt of the hydroxyl group on the molecules that react will react with the lactone ring.

The lactone ring-opening reaction provides chain extension of the molecule if sufficient amounts 25 of the lactone are present. The relative amounts of the carbamate or urea compound and the lactone can be varied to control the degree of chain extension. The opening of the lactone ring with a Shydroxyl or amine group results in the formation of an ester or amide and an OH group. The OH group can then 0 ce react with another available lactone ring, thus resulting in chain extension. The reaction is thus controlled by the proportion of lactone in the reaction mixture to the amount of initiator compound In the practice of the present invention1 the ratio of equivalents of lactone from to equivalents of 11 active hydrogen groups on is preferably from 0.1:1 to 10:1, and more preferably from 1:1 to 5:1.

When the lactone is opened with an acid, the resulting compound has an acid group, which can then be converted to a hydroxyl group by well-known techniques such as reaction with ethylene oxide.

A compound having a hydroxyl active hydrogen group can also be reacted with a hydroxy carboxylic acid to form the carbamate- or ureafunctional compound Useful hydroxy carboxylic acids include dimethylhydroxypropionic acid, hydroxy stearic acid, tartaric acid, lactic acid, 2hydroxyethyl benzoic acid, and N-(2hydroxyethyl)ethylene diamine triacetic acid. The reaction can be conducted under typical transesterification conditions, temperatures from room temperature to 150 0 C. with transesterification catalysts such as such as calcium octoate, metal hydroxides KOH), Group I or II metals Na, 20 Li), metal carbonates K 2

CO

3 which may be enhanced by use in combination with crown ethers, metal oxides dibutyltin oxide), metal alkoxides (e.g, NaOCH 3 Al(OC 3

H

7 3 metal esters stannous octoate, calcium octoate, or protic acids 25 H 2 S0 4 MgCO 3 or Ph 4 SbI. The reaction may also be Sconducted at room temperature with a polymer-supported catalyst such as Amberlyst-15® (Rohm Haas) as described by R. Anand, Synthetic Communications, 24(19), 2743-47 (1994), the disclosure of which is incorporated herein by reference.

In another embodiment, the above-described compound that is the reaction product of a compound having at least one carbamate or urea group (or a group that can be converted to carbamate or urea) and an active hydrogen group with a lactone or hydroxy carboxylic acid may be further reacted with a compound that is reactive with the hydroxyl 12 groups on a plurality of molecules of that reaction product, but that is not reactive with the carbamate or urea groups thereon. Thus, in the final product, the residue of compound can be described as a core to which a plurality of carbamate- or urea-functional residues of reaction product are attached. It is also contemplated that the reaction product may be admixed with other compounds comprising a hydroxyl group plus a carbamate or urea group hydroxypropyl carbamate) prior to the reaction with compound In such a case, the resulting reaction product mixture will reflect the stoichiometric ratio of reaction product to such other compounds.

15 Compounds that are useful as include polyisocyanates, dialkyl carbonates, cyclic carbonates,

CO

2 phosgene, acetals, cyclic or linear phosphazene, substituted or unsubstituted cyclic siloxanes or silanes, or substituted or unsubstituted linear 20 siloxanes or silanes, which may be described by the formula SiXmRn where X is a group that is reactive with protons, such as a halide, alkoxy, hydride, or acetate, C R is a group that is non-reactive with protons such as alkyl, silane, or siloxane, m=2-4, and m+n=4, SO 2 25 POC1 3 POC12R where R is alkyl or aryl. With certain of the compounds a diol may also be included in the reaction mixture to obtain chain extension with carbamate or urea termination. Tbis can be done, for example, with phosgene where the phosgene/diol reaction results in chain extension and the reaction of phosgene with the reaction product results in chain termination with a carbamate or urea group.

The polyisocyanate can be an aliphatic polyisocyanate, including a cycloaliphatic polyisocyanate or an aromatic polyisocyanate. Useful aliphatic polyisocyanates include aliphatic diisocyanates such as ethylene diisocyanate, 1,2-

I

13 diisocyanatopropane, 1,3-diisocyanatopropane, 1,6diisocyanatohexane, 1,4-butylene diisocyanate, lysine diisocyanate, 1,4-methylene bis-(cyclohexyl isocyanate) and isophorone diisocyanate. Useful aromatic diisocyanates and araliphatic diisocyanates include the various isomers of toluene diisocyanate, metaxylylenediioscyanate and para-xylylenediisocyanate, also 4-chloro-l,3-phenylene diisocyanate, tetrahydro-naphthalene diisocyanate, 4,4'-dibenzyl diisocyanate and 1,2,4-benzene triisocyanate can be used. In addition, the various isomers of tetramethyl xylylene diisocyanate can be used.

Oligomeric or polymeric polyisocyanates prepared by reaction of an excess of monomeric polyisocyanates with 15 a polyol may be used. Also, isocyanurates such as the isocyanurate of isophorone diisocyanate or the isocyanurate of hexamethylene diisocyanate may be used.

Biurets of isocyanates such as DESMODUR® N100 from Mobay may also be useful.

20 Dialkyl carbonates, cyclic carbonates, CO 2 diphenyl carbonates, or phosgene may be used as compound to react with and link two reaction product compounds via a carbonate linking group. When phosgene is used, 25 phosgene may be added to a solution of the reaction product at a molar ratio of about 1 mole phosgene to 2 moles reaction product (or 2 moles reaction product plus other hydroxy carbamate or urea- compounds such as hydroxypropyl carbamate). This reaction may be conducted at temperatures of less than 7°C. or under pressure in order to maintain phosgene in its liquid state, or alternatively, gaseous phosgene may be bubbled through the system. A salting base NaOH) may be used to help drive the reaction. The reaction may be conducted in virtually any aprotic solvent at temperatures of -20"C. to 80 0 C. and 14 pressures of atmospheric to 40 psi.

Cyclic carbonates or dialkyl carbonates may be used as compound to react with the reaction product by heating 200°C.) the appropriate molar mixture (2 moles reaction product plus any other hydroxy carbamate or urea and 1 mole cyclic carbonate or dialkyl carbonate) with a transesterification catalyst such as calcium octoate. Useful dialkyl carbonates include diethyl carbonate, dimethyl carbonate, dipropyl carbonate, diphenyl carbonate, and dibutyl carbonate.

Useful cyclic carbonates include propylene carbonate, glycerine carbonate, and dimethyl ethylene carbonate.

Cyclic carbonates may also be formed from any 15 unsaturated bond by reaction of the unsaturated bond with peroxide to form an oxirane ring, followed by reaction with CO 2 to form the cyclic carbonate. Useful catalysts include metal hydroxides KOH), Group I or II metals Na, Li), metal carbonates 20 K 2

CO

3 which may be enhanced by use in combination with crown ethers, metal oxides dibutyltin oxide), metal alkoxides NaOCH 3 Al(OC 3

H

7 3 metal esters stannous octoate, calcium octoate), or protic acids H 2 S0 4 MgCO 3 or Ph 4 SbI. Any 25 solvents used should be inert to transesterification.

The catalysts and/or reaction conditions may need to be adjusted to minimize transesterification of the ester groups from the ester groups in the reaction product. CO 2 may also be used as compound (A) under similar conditions with similar catalysts plus it may be used at pressures of 1 to 40 atm.

Compounds having inorganic reactive groups may also be used to react with the hydroxyl groups of the reaction product. These include phosphorus compounds such as POC13 or hexachlorocyclotriphosphazene, SO 2 sources such as SO 3 or SO 2 C1 2 or silane-based systems such as substituted 15 or unsubstituted cyclic siloxanes or silanes, or substituted or unsubstituted linear siloxanes or silanes, which may be described by the formula SiXmRn where X is a group that is reactive with protons, such as a halide, alkoxy, hydride, or acetate, R is a group that is non-reactive with protons such as alkyl, silane, or siloxane, m=2-4, and m+n=4.

Phosphorus-containing compounds such as phosphazene-based compounds hexachlorocyclotriphosphazene) or POC13 may be used as compound to react with the reaction product. In a typical reaction, one equivalent (based on chlorine content) of the phosphorus reagent is dissolved in a dry ether solvent 15 such as diethyl ether of tetrahydrofuran to form a solution of approximately 50%. 1.5 equivalents of sodium hydride are added followed by one equivalent of the reaction product (or (2) "reaction product plus other hydroxy carbamate or urea 20 compounds). The mixture is allowed to exotherm to the reflux temperature of the solvent, with the reaction temperature controlled by the addition rate of the reaction product. After addition of the reaction product is complete, the 25 reaction mixture is heated to reflux and held for 2-3 hours. The mixture is then cooled, filtered to remove sodium chloride and any unreacted sodium hydride, and the solvent removed under vacuum.

Silane-based compounds may also be used as compound Such compounds may be described by the formula SiXmRn where X is a group that is reactive with protons, such as a halide, alkoxy, hydride, or acetate, R is a group that is nonreactive with protons such as alkyl, silane, or siloxane, m=2-4, and m+n=4.

These compounds may react with the reaction product in any dry aprotic solvent tetrahydrofuran) under conditions known in the art, 16 which may depend on the nature of the X group. When X is a hydride, the reaction is preferably begun with chilled reactants under an inert atmosphere using catalysts such as tin catalysts.

After the addition of materials is complete, and dry methanol is added to react with any free remaining Si-H bonds. If X is a halide, the reaction is preferably begun under an inert atmosphere at room temperature.

The mixture is then heated to reflux to drive the reaction to completion. HC1 is given off as a byproduct. If X is alkoxy, the reaction is preferably begun under an inert atmosphere at room temperature, which may be maintained for the duration of the reaction. A molecular sieve may be used to absorb the 15 alcohol side product that is formed. Slightly basic or acidic pH will accelerate this reaction; however, it will also accelerate the formation of Si-O-Si bonds.

For SO 2 sources, the SO 3 can be reacted with the by bubbling SO 3 through the (2) 20 reaction product if it is in liquid form or by dissolving the compound in a solvent and then bubbling SO 3 through the solution. The reaction 'of SO 2 C1 2 with the compound may be assisted by the pre-reaction of compound 25 with Na or NaOR (where R is an organic radical).

In another embodiment, the hydroxyl group on the reaction product may be converted to .carbamate or urea by reaction with a compound which is reactive with the reaction product to convert a hydroxyl group thereon to a carbamate or urea group, or which comprises a group that is reactive with a hydroxyl group thereon and also a carbamate or urea group or group that can be converted to carbamate or urea.

A number of compounds may be used as compound to convert a hydroxyl group on the reaction product to a carbamate group. Hydroxyl 17 groups can be converted to carbamate groups by reaction with a monoisocyanate methyl isocyanate) to form a secondary carbamate group or with cyanic acid to form a primary carbamate group unsubstituted carbamates). This reaction is performed preferably in the presence of a catalyst as is known in the art. A hydroxyl group can also be reacted with phosgene and then ammonia to form a compound having primary carbamate group(s), or by reaction of a hydroxyl with phosgene and then a primary amine to form a compound having secondary carbamate groups.

Various compounds can be used as compound that have a group that is reactive with the hydroxyl group on the reaction product 15 and also a carbamate or urea group or a group that can be converted to carbamate or urea. Alkyl carbamates methyl carbamate, butyl carbamate) or substituted alkyl carbamates hydroxypropyl carbamate) can be transesterified with the hydroxyl 20 group on the reaction product. This reaction is performed under heat, preferably in the presence of a catalyst such as an organometallic catalyst dibutyltin dilaurate). A methylol acrylamide can be reacted with the hydroxyl group on 25 the reaction product and then converted to carbamate. In this reaction, the unsaturated bond is then reacted with peroxide, CO 2 and ammonia as described above. The epoxy groups are then reacted with CO 2 to form cyclic carbonate groups, which are converted to carbamate groups by reaction with ammonia.

Partially-blocked toluene diisocyanate can also be used as compound In one embodiment, the unblocked isocyanate on the partially-blocked toluene diisocyanate can be reacted with the hydroxyl group on the reaction product. The other isocyanate can then be unblocked and reacted with a hydroxyalkyl carbamate hydroxypropyl carbamate) 18 or a hydroxy area hydroxyethyl ethylene urea).

Alternatively, the unblocked isocyanate can be reacted with a hydroxyalkyl carbamate hydroxypropyl carbamate) or a hydroxy urea hydroxyethyl ethylene urea), followed by unblocking of the other isocyanate group and reaction with the hydroxyl group on the reaction product. Other polyisocyanates can be used to append carbamate or urea groups onto the hydroxyl group on the reaction product, but they will result in competing side reactions where the polyisocyanate reacts with more than one molecule or more than one hydroxyalkyl carbamate or hydroxy urea.

In yet another embodiment, a polyol, amino 15 alcohol, or polyamine (typically a diol or diamine, although polyols or polyamines of higher functionality may also be used) is reacted with a lactone or a hydroxy carboxylic acid to form a polyol having at least one ester or amide group derived from the lactone 20 ring-opening reaction or the hydroxy carboxylic acid condensation reaction. The hydroxyl groups thereon can then be converted to carbamate or urea groups or reacted with a compound having carbamate or urea groups or groups that can be converted to carbamate or urea by "i 25 any of the techniques described above. Polyols derived from lactone ring-opening reactions are commercially available under the Tone® polyol product line of Union Carbide Corporation, such as Tone® 0200, Tone® 2221, Tone® 0301, or Tone® 0310) or may be prepared by ring opening a lactone with virtually any polyol or polyamine under the conditions described above for lactone ring opening. Useful polyols can include 1,4butane diol, 1,6-hexane diol, urethane polyols (which may be formed by reaction of polyisocyanates with an excess of polyol or by the techniques described in U.S.

Patent 5,134,205 of Blank), dimer fatty alcohol, and the like. Useful polyamines can include isophorone 19 diamine, bis-[diaminomethyl cyclohexane], bis-[4aminophenyl methane], polyethylene imine (sold as Polymin® by BASF), and triaminononane. Useful amino alcohols include hydroxyethyl amine, ol, and aminomethyl propanol.

The composition of the invention is cured by a reaction of the carbamate- or urea-functional compound with a component that is a compound having a plurality of functional groups that are reactive with the carbamate or urea groups on component Such reactive groups include active methylol or methylalkoxy groups on aminoplast crosslinking agents or on other compounds such as phenol/formaldehyde adducts, siloxane or silane groups, and anhydride 15 groups. Examples of compounds include melamine formaldehyde resin (including monomeric or polymeric melamine resin and partially or fully alkylated melamine resin), urea resins methylol ureas such as urea formaldehyde resin, alkoxy ureas such as 20 butylated urea formaldehyde resin), N-methylol acrylamide emulsions, isobutoxy methyl acrylamide emulsions, polyanhydrides polysuccinic anhydride), and siloxanes or silanes dimethyldimethoxy silane). Aminoplast resin such as melamine formaldehyde resin or urea formaldehyde resin are especially preferred. Also preferred are aminoplast resins where one or more of the amino nitrogens is substituted with a carbamate group for use in a process with a curing temperature below 150 0 as described in U.S. patent 5,300,328.

A solvent may optionally be utilized in the coating composition used in the practice of the present invention. The coating composition according to the present invention can be applied without solvent, especially if the degree of chain extension for component is limited. However, in many cases, it is desirable to use a solvent in the coating 20 composition as well. This solvent should act as a solvent with respect to both the carbamate- or ureafunctional compound as well as the component In general, depending on the solubility characteristics of components and the solvent can be any organic solvent and/or water. In one preferred embodiment, the solvent is a polar organic solvent.

More preferably, the solvent is a polar aliphatic solvent or polar aromatic solvents. Still more preferably, the solvent is a ketone, ester, acetate, aprotic amide, aprotic sulfoxide, or aprotic amine.

Examples of useful solvents include methyl ethyl ketone, methyl isobutyl ketone, amyl acetate, ethylene glycol butyl ether-acetate, propylene glycol monomethyl 15 ether acetate, xylene, N-methylpyrrolidone, or blends of aromatic hydrocarbons. In another embodiment, the solvent can be water or a mixture of water with co- *solvents.

The coating composition used in the practice 20 of the invention may include a catalyst to enhance the cure reaction. For example, when aminoplast compounds, especially monomeric melamines, are used as component S: a strong acid catalyst may be utilized to enhance the cure reaction. Such catalysts are well-known in 25 the art and include, for example, R-toluenesulfonic S: acid, dinonylnaphthalene disulfonic acid, dodecylbenzenesulfonic acid, phenyl acid phosphate, monobutyl maleate, butyl phosphate, and hydroxy phosphate ester. Other catalysts that may be useful in the composition of the invention include Lewis acids, zinc salts, and tin salts.

Although a solvent may be present in the coating composition in an amount of from about 0.01 weight percent to about 99 weight percent, it is preferably present in an amount of less than 30%, more preferably less than 20% and most preferably less than The coating composition preferably has a VOC (VOC 1 21 is defined herein as VOC according to ASTM D3960) of less than 3.0 Ibs/gal, more preferably less than Ibs/gal, and most preferably less than 1.0 Ibs/gal.

Coating compositions can be coated on the article by any of a number of techniques well-known in the art. These include, for example, spray coating, dip coating, roll coating, curtain coating, and the like. For automotive body panels, spray coating is preferred. One advantage that can be achieved with coating compositions according to the invention is that coatings with a high degree of flexibility can be prepared. Accordingly, in a preferred embodiment, the substrate onto which the coating is applied is flexible, such as plastic, leather, or textile 15 substrates.

Any additional agent used, for example, surfactants, fillers, stabilizers, wetting agents, dispersing agents, adhesion promoters, UV absorbers, HALS, etc. may be incorporated into the coating 20 composition. While the agents are well-known in the prior art, the amount used must be controlled to avoid adversely affecting the coating characteristics.

S In one preferred embodiment, the coating composition according to the invention is preferably 25 utilized in a high-gloss coating and/or as the clearcoat of a composite color-plus-clear coating.

.o High-gloss coatings as used herein are coatings having a 200 gloss (ASTM D523-89) or a DOI (ASTM E430-91) of at least 80. In other preferred embodiments, the coating composition may be utilized to prepare highgloss or low-gloss primer or enamel coatings.

When the coating composition of the.invention is used as a high-gloss pigmented paint coating, the pigment may be any organic or inorganic compounds or colored materials, fillers, metallic or other inorganic flake materials such as mica or aluminum flake, and other materials of kind that the art normally names as 22 pigments. Pigments are usually used in the composition in an amount of 2% to 350%, based on the total weight (not including solvent) of components A and B a P:B ratio of 0.02 to When the coating composition according to the invention is used as the clearcoat of a composite color-plus-clear coating, the pigmented basecoat composition may any of a number of types well-known in the art, and does not require explanation in detail herein. Polymers known in the art to be useful in basecoat compositions include acrylics, vinyls, polyurethanes, polycarbonates, polyesters, alkyds, and siloxanes. Preferred polymers include acrylics and polyurethanes. In one preferred embodiment of the *15 invention, the basecoat composition also utilizes a carbamate-functional acrylic polymer. Basecoat polymers are preferably crosslinkable, and thus 9 comprise one or more type of cross-linkable functional S. groups. Such groups include, for example, hydroxy, 20 isocyanate, amine, epoxy, acrylate, vinyl, silane, and acetoacetate groups. These groups may be masked or blocked in such a way so that they are unblocked and available for the cross-linking reaction under the desired curing conditions, generally elevated 25 temperatures. Useful cross-linkable functional groups Sinclude hydroxy, epoxy, acid, anhydride, silane, and acetoacetate groups. Preferred crosslinkable o functional groups include hydroxy functional groups and amino functional groups.

Basecoat polymers may be self-cross-linkable, or may require a separate cross-linking agent that is reactive with the functional groups of the polymer.

When the polymer comprises hydroxy functional groups, for example, the cross-linking agent may be an aminoplast resin, isocyanate and blocked isocyanates (including isocyanurates), and acid or anhydride functional cross-linking agents.

23 The coating compositions described herein are preferably subjected to conditions so as to cure the coating layers. Although various methods of curing may be used, heat-curing is preferred. Generally, heat curing is effected by exposing the coated article to elevated temperatures provided primarily by radiative heat sources. Curing temperatures will vary depending on the particular blocking groups used in the crosslinking agents, however they generally range between 93°C. and 177 0 C. The coating composition according to the present invention is curable even at relatively low cure temperatures. Thus, in a preferred embodiment, the cure temperature is preferably between 115°C. and 150 0 and more preferably at temperatures between 15 115 0 C. and 1380C. for a blocked acid catalyzed system.

For an unblocked acid catalyzed system, the cure temperature is preferably between 82 0 C. and 99 0 C. The curing time will vary depending on the particular components used, and physical parameters.such as the thickness of the layers, however, typical curing times range from 15 to 60 minutes, and preferably 15-25 minutes for blocked acid catalyzed systems and 10-20 minutes for unblocked acid catalyzed systems.

goo*: •The invention is further described in the 25 following examples.

Preparation 1 O A clean 5-liter three-necked round bottomed flask was equipped with an agitator, condenser, thermocouple, and nitrogen line. To this apparatus was added 1735.0 g e-caprolactone, 761.9 g hydroxypropyl carbamate, 234 g xylene, and 4.4 g stannous octoate.

The mixture was stirred under nitrogen atmosphere and heated to a temperature of 130"C. Temperature was maintained for a period of 6 hours to complete the synthesis, and then cooled.

24 Example 1 Coating Composition A clearcoat composition was prepared by mixing 1000 g of Preparation 1, 337.4 g monomeric fully metholated melamine, and 6.1 g dodecylbenzyl sulfonic acid.

This composition was spray-applied to a variety of substrates using a conventional air atomization siphon gun. Both rigid and flexible substrates were coated. A portion of the panels were applied wet on wet over conventional high solids basecoat. For these systems, the basecoat (an industry standard high-solids OH acrylic/melamine system) was applied, followed by a 10-minute ambient flash, at which point the above-described coating composition was applied. After an additional 5 minutes ambient flash, the panels were baked at 250 0 F. for 30 minutes.

The coating composition of the Example resulted in a contiguous cured hard clear film. The measured VOC of the clearcoat mixture was found to be 20 1.2 lbs/gal (140 kg/m 3 Preparation 2 A clean 12-liter three-necked round bottomed flask was equipped with an agitator, condenser, thermocouple, and nitrogen line. To this apparatus 25 were added 6033 g E-caprolactone, 2516 g hydroxypropyl carbamate, 450 g toluene, and 15 g stannous octoate.

The mixture was stirred under nitrogen atmosphere and heated to a temperature of 130 0 C. Temperature was maintained for a period of 6 hours to complete the synthesis, and then cooled.

Preparation 3 2092 g of the component prepared according to Preparation 2, 412 g 1,6-hexamethylene diisocyanate was added under nitrogen atmosphere to a 5-liter threenecked round bottomed flask was equipped with an agitator, condenser, thermocouple, and nitrogen line.

The mixture was slowly heated to 60°C. at which point 25 the mixture exothermed. The mixture was cooled such that a maximum exotherm temperature of 99°C. was reached, after which a batch temperature of 86 0 C. was maintained for a period of 4.25 hours. The mixture was cooled and diluted with 286.7 g n-butyl acetate.

Example 2 A clearcoat was prepared by mixing 166 g ofthe material prepared according to Preparation 3, 33.7 g monomeric fully methylated melamine, 5.22 g of a solution of blocked dodecylbenzyl sulfonic acid active), 5.22 g Tinuvin® 1130, 0.87 g polyacrylate additive solution, 1.45 g surface modifier additive solution, 4.25 g n-butyl acetate and 42.5 g ethylene glycol butyl ether acetate.

The coating composition was spray-applied to a variety of substrates using a conventional air atomization siphon gun. Both rigid and flexible substrates were coated. A portion of the panels were applied wet on wet over conventional high solids basecoat. For these systems, the basecoat (an industry standard high-solids OH acrylic/melamine system) was applied, followed by a 10 minute 200 0 F. (93.5 0

C.)

flash. After cooling, the coating mixture was applied directly to the basecoat. After an additional 25 minutes ambient flash, the panels were baked at 250 0

F.

•(121 0 for 30 minutes.

The coating composition of the Example resulted in a contiguous cured hard clear film. The measured VOC of the clearcoat mixture was found to be 3.07 lbs/gal (36.8 kg/m3).

Preparation 4 A three-necked 1-liter flask was equipped with an agitator, thermocouple, nitrogen line, and condenser. To the flask were added 59.5 parts Hydroxypropyl carbamate, 171.2 parts E-caprolactone, 98.8 parts xylene, and 0.4 parts stannous octoate under nitrogen atmosphere. The mixture was heated to 130 0

C.

26 for a period of 10 hours, at which point 0.2 parts additional stannous octoate were added. The mixture was heated to 145 0 C. for a period of 1 hour and cooled.

Preparation A three-necked 1-liter flask was equipped with agitator in the center neck, a thermocouple and nitrogen line in one neck and a trap in the third to condense and collect volatiles with a mixture of dry ice and isopropanol.

125.0 parts of Preparation 4, 11.2 parts diethyl carbonate, and 4.0 parts dibutyltin dimethoxide were added to the flask under nitrogen atmosphere.

Heat was applied such that temperature was maintained around 100°C. for three hours during which time volatiles were collected in the trap. Recovered ethanol as well as diethyl carbonate distilled to trap were monitored by gas chromatograph. Periodically, additions of diethyl carbonate were made to the flask to replenish loss to the trap. The mixture was heated 20 for an additional period of 10.5 hours at temperatures ranging from 90-132°C. with continued monitoring of recovered ethanol and replenishment of diethyl carbonate as needed.

The resulting resin was reduced with 29.8 parts amyl acetate.

Example 3 A clearcoat was prepared by combining parts Preparation 5, 2 parts Resimene® 747, 1.8 parts Solvesso® Aromatic 100 solvent mixture, and 0.48 parts dodecylbenzylsulfonic acid. Once homogeneous, the mixture was drawn over a glass plate, and cured at 250 0 F. (121°C.) for 30 minutes. The result was a tough, flexible, solvent-resistant coating.

Preparation 6 In a three necked three liter flask equipped with an agitator, thermocouple, nitrogen line, and condenser, were added 841.5 g hydroxypropyl carbamate, 27 806.9 g e-caprolactone, and 2.8g stannous octoate under nitrogen atmosphere. The mixture was heated to a temperature of 130°C. for a period of 5.5 hours.

Preparation 7 To 200 parts of Preparation 6 was added 102.7 parts of urea, and 1.6 parts of triethylene diamine. The system was heated to 130 0 C. and held for 1 hour. The system was then heated to 140 0 C. for 5.5 hours. This resulted in the formation of cyanic acid from the thermal decomposition of the urea, which reacted with the hydroxyl groups on the Preparation 1 compound to form carbamate groups. The resulting solid product was washed with ethyl acetate, dissolved in methylene chloride, and filtered. The methylene chloride was then removed by evaporation to 15 yield the final product.

Example 4 The following components were mixed and drawn down on glass substrate to form an 8 mm-thick layer: 6.2g Preparation 7 20 1.7g Resimene® 747 melamine resin 0.04g dodecylbenzene sulfonic acid 10g amyl acetate The coated glass substrate was baked at 250 0

F.

(121 0 for 30 minutes, resulting in a clear tack-free film that passed 200 methylethyl ketone double rubs with only surface scratches.

The invention has been described in detail with reference to preferred embodiments thereof. It should be understood, however, that variations and modifications can be made within the spirit and scope of the invention.

In the claims which follow and in the preceding P ALI/ description of the invention, except where the context 29526.DOC 27arequires otherwise due to express language or necessary implication, the words "comprises" and "comprising" are used in the sense of "includes" and "including", i.e. the features specified may be associated with further features in various embodiments of the invention.

.o a go 9526 4

I

292

Claims

1. A method of making a carbamate- or urea-functional compound having at least one ester or amide group comprising the step of reacting a lactone or hydroxy carboxylic acid with a compound comprising a carbamate or urea group or a group that can be converted to a carbamate or urea group, and an active hydrogen group capable of reacting with the hydroxycarboxylic acid or in a ring-opening reaction with a lactone.

2. A method according to claim 1, wherein said compound comprises a carbamate group or group that can be converted to carbamate.

3. A method according to claim 1, wherein said compound comprises a urea group or group that can be 15 converted to urea.

4. A method according to claim 1, wherein said active hydrogen group on compound is a hydroxyl group. a*

5. A method according to claim 1, wherein said active hydrogen group on compound is an amino group. 20

6. A method according to claim 1, wherein said compound is a hydroxyalkyl carbamate or hydroxyalkyl cyclic carbonate.

7. A method according to claim 1, wherein compound is a P-hydroxy carbamate that is a product of ring- opened cyclic carbonate.

8. A method according to any of the preceding claims, wherein said compound is reacted with a lactone.

9. A method according to claim 8, wherein the ratio of equivalents of lactone to equivalents of active hydrogen groups on is from 1:1 to 10:1. A method according to claim 8, wherein the ratio of equivalents of lactone to equivalents of active hydrogen N groups on is from 1:1 to 5:1.

29526.DOC -29- 11. A method according to claim 8, wherein said lactone and said compound are reacted in the presence of an acid catalyst, a base catalyst, an organometallic catalyst, or a sodium catalyst. 12. A method according to any of the preceding claims, further comprising the step of reacting the reaction product of said compound and said lactone or hydroxy carboxylic acid with a compound that is reactive with hydroxyl groups on a plurality of molecules of said reaction product, but that are now reactive with the carbamate or urea groups said reaction product. 13. A method according to claim 12, wherein said compound that is reactive with hydroxyl groups on said reaction Sproduct is a polyisocyanate. 14. A method according to claim 12, wherein said compound that is reactive with hydroxyl groups on said reaction product is carbon dioxide. e S. 15. A method according to claim 12, wherein said compound that is reactive with hydroxyl groups on said reaction 20 product is a dialkyl carbonate. 16. A method according to claim 12 wherein said compound that is reactive with hydroxyl groups on said reaction product is a multifunctional organotitanate, organo- aluminum, or organo-tin compound. 17. A method according to any of the preceding claims, further comprising the step of reacting the reaction product of said compound and said lactone or hydroxy carboxylic acid with a component to convert a hydroxyl group on said reaction product to a carbamate or urea group. 18. A method according to any of the preceding claims, further comprising the step of reacting the reaction product of said compound and said lactone or 29526.DOC -29a- hydroxy carboxylic acid with a compound comprising a group that is reactive with a hydroxyl group on said reaction product and a carbamate or urea group or group that can be converted to carbamate or urea. 19. A carbamate- or urea-functional compound having at least one ester or amide group that is the reaction product of a lactone or hydroxy carboxylic acid with a compound comprising an active hydrogen group and a carbamate or urea group or a group that can be converted to a carbamate or urea group. A compound according to claim 19, wherein the active hydrogen group on compound is a hydroxyl group. 21. A compound according to claim 19, wherein the e a, ae a.e a *oo to *o 29526.DOC 4 I' active hydrogen group on compound is an amino group. 22. A compound according to claim 19, wherein said ester-containing compound comprises carbamate and hydroxyl functional groups. 23. A compound according to claim 19, wherein said ester-containing compound comprises urea and hydroxyl functional groups. 24. A compound according to claim 19, wherein compound is a hydroxyalkyl carbamate or a hydroxyalkyl cyclic carbonate. A compound according to claim 19, wherein compound is a 1-hydroxy carbamate that is a product of a ring- opened cyclic carbonate. 26. A compound according to claim 19, wherein said compound is reacted with a lactone. 27. A compound according to claim 26, wherein the ratio of equivalents of lactone to equivalents of active hydrogen groups is from 0.1:1 to 10:1. 28. A compound according to claim 26, wherein the ratio o* of equivalents of lactone to equivalents of hydroxyl groups is from 1:1 to 5:1. 29. A compound according to claim 19, wherein said compound is a hydroxyalkyl carbamate or a hydroxyalkyl cyclic carbonate. 30. A compound according to claim 26, wherein said lactone and said compound are reacted in the presence of an acid catalyst, a base catalyst, an organometallic catalyst, or a sodium catalyst. 31. A compound according to any of claims 19-30, wherein the reaction product of said compound and said lactone or hydroxy carboxylic acid is further reacted with a compound that is reactive with hydroxyl groups on a plurality of molecules of said reaction product, but that are not reactive with the carbamate or urea groups said reaction product. 32. A compound according to claim 31, wherein said compound that is reactive with hydroxyl groups on said reaction product is a polyisocyanate. -31- 33. A compound according to claim 31, wherein said compound that is reactive with hydroxyl groups on said reaction product is carbon dioxide. 34. A compound according to claim 31, wherein said compound that is reactive with hydroxyl groups on said reaction product is a dialkyl carbonate. A compound according to claim 31, wherein said compound that is reactive with hydroxyl groups on said reaction product is a multifunctional organotitanate, organo-aluminum, or organo-tin compound. 36. A compound according to any of claims 19-35, wherein the reaction product of said compound and said lactone or hydroxy carboxylic acid is further reacted with a component to convert a hydroxyl group on said reaction 15 product to a carbamate or urea group. 37. A compound according to any of claims 19-35, wherein the reaction product of said compound and said lactone or hydroxy carboxylic acid is further reacted with a compound comprising a carbamate or urea group or group S: 20 that can be converted to carbamate or urea and a group that is reactive with a hydroxyl group on said reaction product. 38. A curable coating composition comprising a compound comprising a plurality of functional 25 crosslinking groups, at least one of which is a carbamate or urea functional group, which compound also includes at least one ester or amide group derived from a reaction of an active hydrogen group with a lactone ring or a hydroxy carboxylic acid, and a curing agent comprising a plurality of groups that are reactive with the functional groups on compound 29526 -32- 39. A curable coating composition according to claim 38, wherein said compound comprises at least one carbamate group. A curable coating composition according to claim 38, wherein said compound comprises at least one urea group. 41. A curable coating composition according to claim 39, wherein said compound comprises a plurality of carbamate or urea groups. 42. A curable coating composition according to claim 39, wherein said compound comprises a plurality of carbamate groups. 43. A curable coating composition according to claim 38, wherein said compound comprises at least one hydroxy functional and at least one carbamate or urea functional group. 44. A curable coating composition according to claim 43, wherein said compound comprises at least one hydroxyl functional group and at least one carbamate functional group. :45. A curable coating composition according to any one of 9* claims 38-44, wherein said compound includes at least one polyester segment derived from a lactone ring-opening chain extension reaction. 25 46. A curable coating composition according to any of claims 38-45, wherein said ester or amide group is derived from a reaction of an active hydrogen group with a lactone ring. 47. A curable coating composition according to claim 46, wherein said lactone is E-caprolactone. 48. A curable coating composition according to any of claims 38-47, wherein compound is an aminoplast. 29526.DOC -32a- 49. A curable coating composition according to claim 47, wherein said aminoplast is a melamine resin. A curable coating composition according to any of claims 38-49, having a VOC of less than 3.0 lbs/gal. 51. A curable coating composition according to claim having a VOC of less than 2.0 lbs/gal. 52. A curable coating composition according to claim having a VOC of less than 1.0 lbs/gal. 53. A curable coating composition according to any of claims 38-52, that is a liquid and comprises less than weight percent of nonreactive organic solvent. 54. A curable coating composition according to claim 53, that is a liquid and comprises less than 20 weight percent of nonreactive organic solvent. a* a *oo fto* o *o 29526.DOC -33- A curable coating composition according to claim 53, that is a liquid and comprises less than 10 weight percent of nonreactive organic solvent. 56. A curable coating composition according to any of claims 38-55, that is a clear coating composition. 57. A coating composition according to any of claims 38-56, further comprising a pigment. 58. An article comprising a substrate having thereon a cured coating derived from a coating composition according to any of claims 38-57. 59. An article according to claim 58, wherein said substrate is a flexible substrate. A method of making a carbamate- or urea-functional ester-containing compound substantially as hereinbefore described in any of the Examples. 61. A coating composition substantially as hereinbefore described in any of the Examples. Dated this 4th day of October 1996 BASF CORPORATION By their Patent Attorney GRIFFITH HACK S o o *o *oe *e ooo