Non-isocyanate flexibilizer for coatings

FIELD OF THE INVENTION
The present invention relates to flexibilizer additives useful in automotive paint compositions. More particularly, it relates to non-isocyanate functional flexibilizers which can be added to paint compositions by an end user at point of application or incorporated into a product provided to the end user.
BACKGROUND OF THE INVENTION
Present day automobiles contain flexible plastic parts such as urethane bumpers, filler panels, fender extensions, vinyl tops, and padded dashboards. These parts require greater flexibility than is inherent in many paints, especially lacquers. Conventional non-isocyanate flexibilizer additives, while providing good flexibility, have a detrimental effect on the resultant film by making it very susceptible to dirt pick-up. While isocyanate functional materials can increase resistance to dirt pick-up, the perceived adverse health effects attributed to isocyanates make this an unacceptable approach in some market niches.
SUMMARY OF THE INVENTION
The present invention provides a non-isocyanate flexibilizer additive for coatings which exhibits enhanced resistance to dirt pick-up.
The non-isocyanate functional flexibilizer of the present invention are those described by the following formula I:
B-C(O)-NW-A-NX-C(O)-K
wherein A is selected from the group consisting fundamentally of polyesters, polyamides, polyureas, polyurethanes, acrylics; biuret, allophonate and urethane extended polyesters; wherein B and K are selected from the group consisting of --OR and --Z--R'--SIOR".sub.(3--n) R"".sup.n wherein R' is a divalent lower alkyl radical of from 1 to 18 carbon atoms, R is a lower alkyl radical of from 1 to 18 carbon atoms, Z is a member selected from the group consisting of S and NR'', W and X are selected from H and lower alkyl radicals of from 1 to 10 carbon atoms wherein R'', R", and R"" are H or a lower alkyl radical of from 1-18 atoms, and wherein n is 0, 1 or 2. Also included are biuret and allophonate products of I with isocyanate functional materials.
These compositions may also include a conventional silanol condensation catalyst such as dibutyl tin dilaurate, dibutyl tin diacetate, qamma-aminopropyltrimethoxysilane, amines, alkyl titanate, basic catalyst and acidic catalyst.
The flexibilizers of the present invention are useful in a wide variety of coating systems, including systems, including alkyds, polyesters, acrylic/polyester, alkyd/acrylic, carboxy/epoxy, polyether/urethane, epoxy/polyester, other epoxy, and urea and melamine formaldehyde systems. The flexibilizers are especially useful in conventional acrylic lacquer primers, acrylic lacquer basecoats, acrylic lacquer topcoats, acrylic lacquer clearcoats, acrylic enamel topcoats, high solids urethane acrylic clearcoats, acrylic clearcoats, and high solids single stage. Additional the flexibilizers are useful as a gravel protector coating on automobile parts such as rocker panel areas. They are useful at both ambient temperature cure and force dry conditions and are especially useful in, but not limited to, automotive refinish applications.
In addition, a process for preparing a condensation polymer is disclosed which comprises polymerizing the reactants for a portion of the process time without the removal of condensate, and then polymerizing in the conventional manner. This provides better production processing without excess glycol loss. This process finds utility in preparing the product of the present invention as well as in preparing esterification polymers in general.
Also included are coating compositions which comprise a conventional lacquer and an effective amount of the flexibilizer additive. Typically the additive is present in an amount of from about 2% to about 80% by weight; more preferably from about 4% to about 40% by weight.
Coatings which include the flexibilizer do not contain apparent haze, remain flexible even after heat aging, and do not pick up dirt.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The non-isocyanate functional flexibilizers of the present invention are described by formula I:
B-C(O)-NW-A-NX-C(O)-K
wherein A is selected from the group consisting fundamentally of polyesters, polyamides, polyureas, polyurethanes, acrylics; biuret, allophonate and urethane extended polyesters; wherein B and K are selected from the group consisting of --OR and --Z--R'--SiOR".sub.(3--n) R""".sub.n wherein R' is a divalent lower alkyl radical of from 1 to 18 carbon atoms, R is a lower alkyl radical of from 1 to 18 carbon atoms, Z is a member selected from the group consisting of S and NR'', W and X are selected from H, and lower alkyl radicals of from 1 to 10 carbon atoms wherein R''R", and R"" are H or a lower alkyl radical of from 1-18 carbon atoms, and wherein n is 0, 1 or 2. Also included are biuret and allophonate products of I with isocyanate functional materials.
Particularly preferred, is a non-isocyanate functional flexibilizer wherein B comprises (based on equivalents) from about 10 mole percent to 100 mole percent --Z--R'--SiOR".sub.(3--n) R"".sub.n and from about 90 mole percent to 0 mole percent --OR, wherein R' an R are a lower alkyl radical of from 1 to 18 carbon atoms, Z is selected from the group consisting of S and NR'', and wherein R'' and R"" are H or a lower alkyl radical of from 1-18 carbon atoms.
The flexibilizers are those which result when a hydroxyl-bearing polyester or polyurethane (part 1), is reacted with an excess of multi-functional isocyanate (part 2), which is subsequently reacted with a mono-alcohol such as n-butanol and a functional silane such as gamma-Aminopropyltrimethoxysilane through available excess isocyanate (part 3). A small amount of unreacted isocyanate remains which is reacted with a mono-alcohol such as ethanol.
According to the preferred process for preparing these condensation polymers, the reactants for a portion of the process time are polymerized without the removal of condensate, and then polymerization is continued in the conventional manner. Its utility is pertinent to this invention as well as esterification polymers in general.
Preferred is a flexibilizer in which component A in formula I is an isocyanate functional polyurethane which results when a dipropylene glycol adipate of dipropylene glycol and adipic acid of a calculated number average molecular weight of about 2000 to about 4000 and ahydroxyl number, based on non-volatile, of about 25 to 37, which is then capped with trimethylhexamethyl- enediisocyanate. This polyurethane polyester is subsequently reacted with n-butanol (component B in formula I) and gamma- aminopropyltrimethoxy silane (component K in formula I). In this preferred flexibilizer, referring still to formula I, R' is a propyl alkyl radical (between the amine and the Si), R" a methyl radical (attached to o attached to the Si) and R is a butyl radical.
One may also employ low molecular weight polyesters extended with aliphatic diisocyanate. Also contemplated is the use of polyesters with branching monomers such as pentaerythritol, trimethylol propane, trimethylol propane and the like as well as other diols such as cyclohexane dimethanol. A low Tg, low molecular weight acrylic of less than 25.degree. C. may also be employed.
These flexibilizers may also include a conventional silanol condensation catalyst such as dibutyl tin dilaurate, dibutyl tin diaoetate, gamma-aminopropyltrimethoxysilane, amines, alkyl titanate, basic catalyst and acidic catalyst.
One preferred flexibilizer is an isocyanate terminated polyester reacted (based on isocyanate equivalents) with about 10 to 100 mole percent gamma-Aminopropyltrimethoxysilane, 0 to 90 mole percent n-butanol, 0 to 5 mole percent ethanol, and 0.5 to 2 weight percent dibutyl tin dilaurate catalyst based on total non-volatile.
The additive of the present invention can be applied to and will function well on all interior and exterior automotive flexible parts including urethane bumpers, filler panels, fender extensions, vinyl tops, and padded dashboards. It is also useful as a gravel protector for rocker panel areas. The additive is isocyanate-free, is clear and, when added to acrylic topcoat colors, provides excellent performance properties in refinishing exterior automotive flexible parts and fascia. It is resistant to dirt pick-up, resilient, flexible even at low temperature, fast drying and has high gloss and excellent physical properties. It also provides improved exterior fade resistance, water and gasoline resistance and is durable. It may also be employed in acrylic lacquers designed for use on interior automotive parts.
Also included are flexible coating compositions for metal and plastic substrate, which comprise a coating system and an effective amount of the flexibilizer additive. Typically the additive is present in an amount of from about 2% to about 80% by non-volatile weight; more preferably from about 4% to about 40% by non-volatile weight. These coating compositions may also include conventional additives such as wetting agents, anti-settling agents and ultra violet absorbers.
Coatings which include the flexibilizers of the present invention do not contain apparent haze, remain flexible even after heat aging, and do not pick up dirt when tested as described below.
The following examples are presented in order to illustrate the present invention without limiting its scope. All raw materials (except those prepared in the examples) were commercially available and were used as supplied.
In the following examples, the results were evaluated using the following test methods:
A. Flexibility: painted 5".times.4".times.1/8" polyurethane test panels cured overnight at ambient room temperature were bent around a cylinder (4".times.31/4" diam) once and observed for cracks or paint splitting. If the sample passed flexibility, then the same test panel and cylinder were placed in a cooling chamber at 50.degree. F. for on hour before bending and evaluating for flexibility. If the sample passed, then the test panel was placed in a 140.degree. F. oven for periods of 1 day, 1 week, 1 month, 2 months till failure. Each time the test panel was removed from the 140.degree. F. oven and allowed to cool to room temperature before flexing over the cylinder.
B. Dirt Resistance: painted 5".times.4".times.1/8" polyurethane test panels were cured overnight at ambient room temperature and were tested at room temperature. A Dietz Junior No.20 hurricane lantern (about 12" high including chimney with chimney raised about an inch (total 13") to allow air to reach the wick to give about a 2" flame) with a sooty flame was used to determine dirt resistance. A test panel was placed on the chimney top and exposed to the sooty flame for one minute. The blackened panel was evaluated for dirt resistance by drawing a clean, dry finger across the blackened surface. Removal of all the soot in the finger's path indicated excellent dirt resistance.
C. Water Resistance: two one milliliter deionized water drops were applied to panels that had been cured overnight and the panels were then placed in a 120.degree. F. oven until the water evaporated. One spot wiped clean was compared to an adjacent water spot and rated on a scale of 1-10.
D. Print Resistance: test panels cured overnight were placed into a 120.degree. F. oven for two minutes. A two square inch paper pad (1/2" thick) and 500 gram weight were placed on the test panels for 2 minutes. The panels were then removed from the oven and rated on a scale of 1-10.
E. Gasoline Resistance: one 1 ml. unleaded gasoline was applied for five minutes at room temperature to test panels that had been cured overnight for 5 minutes at room temperature. The panels were then evaluated for film disturbance and recovery.
F. Adhesion Test: test panels cured overnight were cut through to the substrate with a crosshatch knife in perpendicular directions. An adhesive tape was secured firmly to the film then pulled away rapidly. Adhesion was rated on a scale of 1-10.
G. Humidity Resistance: test panels cured for one week were placed into a humidity cabinet (100.degree. F., 100% R. H.) for 24 hours, removed for a 15 minute recovery then checked for adhesion. This cycle was repeated 5 times and panels were rated on a scale of 1-10.
H. Water Spray: test panels cured for one week were placed into a water spray cabinet (72.degree. F.) for 48 hours followed by a 24 hr. recovery at room temperature. Panels were then checked for adhesion. This cycle was repeated 5 times and the panels rated on a scale of 1-10 scale.
I. OUV (GM cycle, accelerated weathering): test panels cured for two weeks were placed into QUV (313 nanometer wavelength) after determining 20 degree gloss. Appearance and gloss were checked weekly and panels were rotated to ensure uniform exposure until failure.
J. Xenon Weatherometer: test panels cured for two weeks were placed into a weatherometer after determining 20.degree. gloss. Appearance and gloss were checked weekly and panels were rotated to ensure uniform exposure until failure.

EXAMPLE
Example 1
Polyester
Part A: A reactor fitted with agitator, addition ports, packed column (with thermocouple probe at its top), reflux condenser, thermocouple probe, and inert gas inlet was charged with commercially available 6380 gm. dipropylene glycol and 6490 gm. of adipic acid. The reactor was purged with nitrogen while the mixture was heated to 99.degree.-105.degree. C. with stirring. A trace stream of nitrogen was passed through the system after purging. At 99.degree.-105.degree. C., 16.2-16.7 gm. of Air Products T-12 (dibutyl tin dilaurate) was added while the reactor continued heating. The reactor began to reflux at about 166.degree. C. with the temperature at the top of the packed column at about 98.degree. C. After about 5.25 hours at reflux, the reactor was cooled under increased nitrogen flow. Acid number was monitored throughout reaction and was approximately 230 on theoretical solids at this point.
Part B: The reactor was fitted with a Barrett trap filled with toluene, below the condenser but after the packed column to receive condensate. The reactor was purged with nitrogen, with a trace flow of nitrogen remaining after purging, while heating Part A to reflux. Condensate began to collect in the trap at about 127.degree. C. (98.degree. C. temperature at top of packed column). As more condensate collected, the top of the packed column dropped to about 83.degree. C. Intermittent temperature rise occurred when the trap was drained of condensate for collection jars. After about 1017 gm. of condensate was formed, the temperature at the top of the packed column began to rise. About 298 gm. of toluene was added to the reactor through the top of the condenser to maintain the packed column head temperature about 83.degree. C. during removal of this 1017 condensate, with an additional 120 added afterwards. A few seconds of intermittent cooling was used when the condenser was overwhelmed. After about 6.5 hours at reflux the acid number was 80 based on theoretical non-volatile. After about 7.25 hours at reflux the nitrogen flow was increased and the batch cooled.
Part C: The reactor with product of Part B was purged with nitrogen, with a trace flow of nitrogen remaining after purging, while heating to reflux. The reactor was held at reflux, adjusting with toluene to maintain temperature below 235.degree. C. using intermittent cooling (and intermittent increases in nitrogen flow) where necessary to make adjustments. About 1036 gm. of toluene was used for adjustment. Samples were removed for acid number monitoring. After about 7.5 hours at reflux, acid number was 1-2. After about 7.75 hours at reflux, the nitrogen flow was increased, and toluene was slowly pumped through a reactor port into the batch blowing over residual water from the batch and reactor risers; the reactor was cooled and nitrogen flow increased even higher. More toluene was added through the condenser. These last two additions totaled about 1473 gm. Total condensate collected from Part A-C Was about 1560 gm. Gas chromatograph revealed only trace dipropylene glycol loss in condensate.
The properties of the resin were 86-87% non-volatile (0.9-1.1 gm. sample in 2-4 ml toluene for 60 minutes at 105.degree.-115.degree. C.); 1-2 acid number based on the above non-volatile, viscosity of Z-Z1, and V-W reduced to 80% with toluene and a hydroxyl number of 23-27 on solution. Differences between determined non-volatile and theoretical are likely the result of solvent loss during processing.
Example 2
Urethane Intermediate
______________________________________A) Toluene 844 Trimethyl-hexamethylenediisocyanate 198 Toluene 160 EXAMPLE 1 1802B) Dibutyl tin dilaurate .82 (Air Products T-12) Toluene 47______________________________________
A flask was charged with A) and equipped with agitator, addition ports, condenser, thermocouple probe, and inert gas inlet. It was then heated to 65.degree.-70.degree. C. under nitrogen blanket. A trace nitrogen flow was maintained throughout procedure. At 65.degree.-70.degree. C. B) was added. Batch was held until isocyanate level was 1.33-1.36 percent and then cooled.
Example 3
______________________________________A) Product of Example 2 300B) Toluene 11 Gamma-Aminopropyltrimethoxysilane 15.9Approximate Amount Out For Sampling (11)C) Ethanol 2.6D) Dibutyl tin dilaurate 2.38 Toluene 10Approximate Amount Out For Sampling (11)E) Toluene 199 Methyl ethyl ketone 374 Propylene glycol monomethyl 35 ether acetate______________________________________
A flask was charged with A) and equipped with agitator, addition ports, condenser, thermocouple probe, and inert gas inlet. It was then heated to 24.degree.-28.degree. C. under nitrogen blanket. A trace flow of nitrogen was maintained throughout procedure. B) was added while cooling to maintain temperature below 37.degree. C. with most of the time below 30.degree. C. Isocyanate level was checked. After about 50 minutes, C) was added and the batch heated to 65.degree.-70.degree. C. and then D) was added. The batch was held until essentially no isocyanate peak was observable on an infrared spectrometer and then E) was added.
Example 4
______________________________________A) Product of SAMPLE 2 380B) n-Butanol 2.2C) Toluene 10 Gamma-Aminopropyltrimethoxysilane 4.6Approximate Amount Out For Sampling (06)D) Ethanol 5.2E) Dibutyl tin dilaurate 2.8 Toluene 10F) Toluene 256 Methyl ethyl ketone 468 Propylene glycol monomethyl 44 ether acetate______________________________________
A flask was charged with A) and B) and equipped with agitator, addition ports, condenser, thermocouple probe, and inert gas inlet. It was heated to 65.degree.-70.degree. C. under nitrogen blanket. A trace of nitrogen was maintained throughout procedure. The material was held at this temperature and isocyanate level monitored until 0.98-1.02 percent (on solution). Batch was cooled down to 25.degree.-28.degree. C. and C) added. Batch was held about 50 minutes temperature maintained below 37.degree. C., and D) was added. Subsequently the material was heated to 65.degree.-70.degree. C. and E) was added. Batch was held at 65.degree.-70.degree. C. until essentially no isocyanate peak was observable on an infrared spectrometer and then F) added.
Example 5
______________________________________A) Product of EXAMPLE 2 600B) n-Butanol 10.6Approximate Removed for Samples (34)C) Toluene 10 Gamma-Aminopropyltrimethyoxysilane 7.2Approximate Amount Out For Sampling (10)D) Ethanol 5E) Dibutyl tin dilaurate 4.3 Toluene 10Approximate Amount Out For Sampling (12)F) Toluene 391 Methyl ethyl ketone 695 Propylene glycol monomethyl 65 ether acetate______________________________________
A flask was charged with A) and B) and equipped with agitator, addition ports, condenser, thermocouple probe, and inert gas inlet. It was heated to 65.degree.-70.degree. under nitrogen blanket. A trace of nitrogen was maintained throughout procedure. The temperature was held seven hours during which isocyanate value was checked. The flask was sealed up, nitrogen stream maintained, and let set overnight. Subsequently it was heated to 65.degree.-70.degree. C. and held about 6 hours, checking isocyanate value, until isocyanate value was 0.30-0.32%. The material was cooled under nitrogen to 25.degree. C. and C) added while cooling to control exotherm. Temperature was kept below 26.degree. C. Product was held about 40 minutes and then D) added. The material was heated to 65.degree.-70.degree. C. and E) added. Material was held at this temperature until essentially no isocyanate peak was observable on an infrared spectrometer and F) added.
Example 6
______________________________________A) Product of EXAMPLE 2 322 n-Butanol 3.8Approximate Removed for Samples (15)B) Toluene 10 Gamma-Aminopropyltrimethoxysilane 7.1Approximate Amount Out For Sampling (06)C) Ethanol 5D) Dibutyl tin dilaurate 2.37 Toluene 10E) Toluene 214 Methyl ethyl ketone 397 Propylene glycol monomethyl 37 ether acetate______________________________________
A flask was charged with A). The flask was equipped with agitator, addition ports, condenser, thermocouple probe, and inert gas inlet. It was heated to 65.degree.-70.degree. C. under nitrogen blanket. A trace of nitrogen was maintained throughout procedure. The temperature was held about 5.5 hours during which isocyanate value was checked. At 0.57-0.59%, material was cooled to 25.degree. C. and C) added while cooling to control exotherm keeping temperature below 33.degree. C. (mostly below 30.degree. C.). After about 45 minutes C) was added to the flask and the flask heated to 65.degree.-70.degree. C. after which D) was added. Material was held at this temperature until no isocyanate peak was observable on an infrared spectrometer. Component E) was then added.
Example 7
______________________________________A) Product of EXAMPLE 2 108.7B) Toluene 10 Gamma-Aminopropyltrimethoxysilane 5.5Approximate Amount Out For Sampling (14)C) Ethanol 1.5D) Dibutyl tin dilaurate .76 Toluene 10E) Toluene 56 Methyl ethyl ketone 128 Propylene glycol monomethyl 12 ether acetate______________________________________
A flask was charged with A) and equipped with agitator, addition ports, condenser, thermocouple probe, and inert gas inlet. The flask was purged with nitrogen and a blanket maintained throughout procedure. The flask was cooled and B) added over about 2 minutes. The temperature rose from about 16.degree. to 20.degree. C. After about 1 hour the flask was heated to about 30.degree. C. After about 40 minutes C) was added and flask heated to 65.degree.-70.degree. C. after which D) was added. Material was held until essentially no isocyanate peak was observable on an infrared spectrometer and E) added.
Example 8
White Acrylic Lacquer Topcoat
______________________________________ Parts by Volume______________________________________Titanium dioxide acrylic lacquer 444.50Product of EXAMPLE 5 333.30Aliphatic/Aromatic/Ester/Ketone 222.20Acrylic Lacquer Thinner 1,000.00% Non Volatile: 20.39% (wt.)______________________________________
The above lacquer, flex agent and lacquer thinner are sold commercially as A-2080, and PNT-90 by BASF Corporation. The experimental material was applied by air atomization over primed cold rolled steel and polyurethane plastic panels. The coating was allowed to cure at ambient room temperature overnight while some panels cured one week prior to testing. Dry film thickness was measured and determined to be approximately 1.8-2.2 mils of white acrylic lacquer. The cured film demonstrated good substrate adhesion, flexibility, dirt (chemical) resistance, etc. as shown below:
______________________________________Gloss (20 degree meter): 58.degree.Humidity (100% R.H. for 96 hours, 100.degree. F.) ExcellentFlexibility: ExcellentDirt Resistance: ExcellentAdhesion: ExcellentWater Spray (72.degree. for 48 hrs with Excellent24 hrs. recovery) 5 cycles:Gasoline Resist: ExcellentWater Spot: ExcellentPrint: ExcellentQ.U.V. (313 nanometer, GM Cycle) ExcellentWeatherometer (Xenon): Excellent______________________________________
Example 9
Acrylic Lacquer Clearcoat
An acrylic lacquer clearcoat was prepared as follows:
______________________________________Acrylic Lacquer Clearcoat 352.90Product of EXAMPLE 5 294.20Aliphatic/Aromatic/Ester/Ketone Acrylic 352.90Lacquer ThinnerTOTAL 1,000.00% Non Volatile: 17.57% (WT.)______________________________________
The above acrylic lacquer clearcoat and lacquer thinner are sold commercially as #727 and PNT-88 by BASF Corporation. This coating was applied by air atomization over APS-422 primed and Alpha-Cryl basecoated cold rolled steel and polyurethane plastic panels.
The coating was allowed to cure at ambient room temperature overnight while some panels cured on week prior to testing. Dry film thickness was measured and determined to be approximately 2.0 mils of clearcoat.
The cured film demonstrated good substrate adhesion, flexibility, dirt resistance etc., as shown below:
______________________________________Gloss (20.degree. head): 70.0Water Spot: GoodFlexibility: ExcellentHumidity: ExcellentDirt Resistance: ExcellentQUV: ExcellentAdhesion: ExcellentWater Spray: ExcellentGas Resistance: ExcellentPrint: Excellent______________________________________
Example 10
Acrylic Primer
An acrylic iron oxide primer was prepared as follows:
______________________________________ Parts by Volume______________________________________Acrylic iron oxide primer 333.30Product of EXAMPLE 5 166.70Aliphatic/Aromatic/Ester/ 500.00Ketone Acrylic Lacquer ThinnerTOTAL 1,000.00% N.V. = 20.95%______________________________________
The above acrylic primer and solvent are sold commercially as APS-422 and PNT-88 by BASF Corporation.
This material was applied by air atomization over cold rolled steel and polyurethane plastic panels. The coating was allowed to cure at ambient room temperature overnight while some panels cured one week prior to testing. The primer film was sanded lightly with 320 grit sand paper prior to being basecoated, topcoated, clearcoated separately with each of the chemical coatings evaluated in this application. Dry film thickness was measured and determined to be approximately 1.5 mils of primer and cured films demonstrated good substrate adhesion and flexibility as indicated in the performance characteristics of each of the coating in this review.
Examples 11 and 12
White and Black Acrylic Enamel
White and Black acrylic enamels were prepared as follows:
______________________________________ Parts by Volume______________________________________White Acrylic enamel 381.0Polyurethane Crosslinker 47.5Product of EXAMPLE 5 381.0Aliphatic/Aromatic/Ketone/Ester 190.5Acrylic Enamel ThinnerTotal 1,000.00% Non Volatile: 30.18% (wt.) 381.0Black Acrylic EnamelPolyurethane Crosslinker 47.5EXAMPLE 5 381.0Aliphatic/Aromatic/Ketone/Ester 190.5Acrylic Enamel ThinnerTOTAL 1,000.0% Non Volatile: 26.33% (wt.)______________________________________
The above acrylic enamels, polyurethane crosslinker and enamel thinner are sold commercially as L-2080, L-403, LH-75 and MS-6 by BASF Corp.
These enamels were applied by air atomization over APS-422 primed cold rolled steel and polyurethane plastic panels. The coatings were allowed to cure at ambient room temperature overnight while some panels cured one week prior to testing. Dry film thickness was measured and determined to be approximately 2.0-2.3 mils of enamel.
The cured films demonstrated good adhesion, flexibility, dirt resistance etc, as shown below:
______________________________________Gloss (20.degree. head) 85.0Water Spot: ExcellentFlexibility ExcellentHumidity: ExcellentDirt Resistance: ExcellentWater Spray: ExcellentAdhesion: ExcellentPrint: ExcellentGas Resistance: Excellent______________________________________
These results also revealed that although this system is isocyanate based, when the new flex additive is introduced in place of #891, the chemical resistance properties are enhanced.
Example 13
White Acrylic Gravel Protector
A white acrylic gravel protector was prepared as follows:
______________________________________ Part by Volume______________________________________White Acrylic Enamel 666.67Product of EXAMPLE 5 333.33TOTAL 1,000.00% Non Volatile: 42.46% (wt.)______________________________________
The above enamel is sold commercially as L-2080 by BASF Corp.
This coating was applied by air atomization over APS-422 primed cold rolled steel. The coating was allowed to cure at ambient room temperature for one week. Dry film thickness was measured and determined to be approximately 5.0 mils of Gravel Protector. The cured film provided for excellent substrate adhesion and had good resistance to stone chipping when tested on the VW-stone-chip machine where it rated equally with isocyanate functional commercial material.
Example 14
Ultra High Solids Polyurethane Acrylic Clearcoat
A high solids polyurethane cross-linked acrylic clearcoat was prepared as follows:
______________________________________ Parts by Volume______________________________________Ultra High Solids Polyurethane Acrylic 444.45Urethane Catalyst 222.22Product of EXAMPLE 5 333.33TOTAL 1,000.00% Non Volatile: 36.11% (wt.)______________________________________
The above ultra high solids polyurethane acrylic clearcoat and urethane catalyst are sold commercially as RV-86 and RV-87 by BASF Corp.
This coating was applied by air atomization over APS-422 primed and white acrylic lacquer basecoated (Alpha-Cryl) cold rolled steel and polyurethane plastic panels.
The coating was allowed to cure at ambient room temperature overnight while some panels cured one week prior to testing. Dry film thickness was measured and determined to be approximately 2.0 mils of clearcoat.
The cured films demonstrated good adhesion, flexibility, dirt resistance etc, as shown below:
______________________________________Gloss (20.degree. head): 86.degree.Water Spot: ExcellentFlexibility: ExcellentHumidity: ExcellentDirt Resistance: ExcellentWater Spray: ExcellentAdhesion: ExcellentQUV: ExcellentGas Resistance: ExcellentPrint: Excellent______________________________________
These test results also revealed that even though this system is isocyanate based, when the new flex additive is introduced in place of #891, some chemical resistance properties are enhanced.
Examples 15, 16, 17
Urethane Acrylic Clearcoats
Three urethane cross-linked acrylic clearcoats were prepared as follows:
______________________________________ Parts by Volume______________________________________Acrylic Urethane clearcoat 571.40Urethane crosslinker 142.90Product of EXAMPLE 5 285.70TOTAL 1,000.00Non Volatile: 29.53% (wt.)Fast cure acrylic urethane clearcoat 571.40Urethane crosslinker 142.90Product of EXAMPLE 5 285 70TOTAL 1,000.00Non Volatile: 29.53% (wt.)High solids acrylic urethane clearcoat 444.50Urethane crosslinker 222.20Product of EXAMPLE 5 333.30TOTAL 1,000.00Non Volatile: 36.15% (wt.)______________________________________
The above acrylic urethane clearcoats and urethane crosslinkers are sold commercially as DC-88, DC-89, DC-90, DH-44 and DH-51 by BASF Corp. These clearcoats were applied by air atomization over DP-20 primed and Diamont basecoated cold rolled steel, and also over Diamont basecoated polyurethane plastic panels; also applied directly over polyurethane plastic panels.
The coatings were allowed to cure at ambient room temperature overnight while some panels cured one week prior to being tested. Dry film thickness was measured and determined to be approximately 2.0 mils of clearcoat.
The cured films demonstrated good adhesion, flexibility, dirt resistance etc. as shown below:
______________________________________Gloss (20.degree. head): 88.degree.Humidity: ExcellentFlexibility: ExcellentGas Resistance: ExcellentDirt Resistance: ExcellentWater Spot: ExcellentAdhesion: ExcellentWater Spray: ExcellentQUV: ExcellentPrint: Excellent______________________________________
COMPARATIVE EXAMPLE 18
An isocyanate functional urethane flexibilizer comprising: 34 percent aliphatic diisocyanate, 9 percent polyether polyol, 57 percent polyester polyol was prepared.
COMPARATIVE EXAMPLES 19-22
The isocyanate flexibilizer of COMPARATIVE EXAMPLE 28 was reacted with gamma-aminopropyltrimethoxysilane with remaining isocyanate reacted with mono-alcohol in proportions listed in the below table:
______________________________________ Clarity of a commercial Approximate percent clear lacquer coating of isocyanate composition comprising equivalents reacted the listed flexibilizer with aminosilane over a black lacquer______________________________________EXAMPLE 19 0% CLEAREXAMPLE 20 25% VERY SLIGHT HAZEEXAMPLE 21 50% HAZYEXAMPLE 22 100% VERY HAZY______________________________________

Non-isocyanate flexibilizer for coatings

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

US Referenced Citations (1)