Claims:We Claim:
1. Multifunctional polyurethane based wetting and dispersing compound comprisingdiisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid, said trans-esterified/esterifiedoil/fatty acid includes a reaction product of oil/fatty acid and select liquid or low melting polyol, adapted for dispersing organic, inorganic pigment and combinations thereof in alkyd paints to thereby achieve high surface activity with variety of pigments.
2. Multifunctional polyurethane as claimed in claim 1 favoring both polar and non-polar functionalities with large unsaturation and having sufficient polar hydroxy functional groups and urethane linkagesbeing free ofany carboxylic and amine functionality.
3. Multifunctional polyurethane as claimed in claims 1 or 2 wherein said diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid has enough polar hydroxy functional groups and urethane linkages based on selective levels of NCO/OH ratio of 0.1-0.30/1.00.
4. Multifunctional polyurethane as claimed in anyone of claims 1-3 having Iodine value of 100-140 gmI2/100 gm, Hydroxyl value of 100-180 mg KOH/gm, and NCO/OH ratio of 0.10-0.30/1.00.
5. Multifunctional polyurethane as claimed in anyone of claims 1-4 wherein said trans-esterified/esterified oil/fatty acid incorporating select liquid or low melting polyol have melting point in the range of 50 to 150?C comprises Trimethylol propane, 2-methyl-1, 3-propanediol, Neopentyl Glycol, Glycerine.
6. Multifunctional polyurethane as claimed in anyone of claims 1-5 wherein said trans-esterified/esterified oil/fatty acid preferably incorporates semi-drying/drying oil including Soyabean oil/fatty acid, monomeric linseed oil/fatty acid.
7. Multifunctional polyurethane as claimed in anyone of claims 1-6 wherein said polyol trans-esterified/esterified semi-drying/drying oil/fatty acid comprises semi-drying/drying oil/fatty acid of iodine value in the range of 125 to 180 (gm I2 /100gms) and incorporated in said polyol trans-esterified/esterified semi-drying/drying oil/fatty acid in the levels of 70-90% preferably 75-85% to provide for resulting Iodine value in the range of 100-140 gm I2/100 gm.
8. Multifunctional polyurethane as claimed in anyone of claims 1-7 wherein said trans-esterified/esterified semi-drying/drying oil/fatty acid has polyol content in the range of 10-27% of said oil/ fatty acid content and having hydroxyl value in the range of 120-200 (mg KOH/gm).
9. Multifunctional polyurethane as claimed in anyone of claims 1-8 wherein said diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid is a reaction product of aliphatic/cycloaliphatic diisocyanate partially reacted to trans-esterified/esterified semi-drying/drying oil/fatty acid incorporating said select polyol, thereby providing for free -OH value of 100-180(mg KOH/gm) of said diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid.
10. Multifunctional polyurethane as claimed in anyone of claims 1-9 wherein said diisocyanate comprises aliphatic/cycloaliphatic diisocyanate includinghexamethylene diisocyanate, Isophorone diisocyanate, etc.
11. Multifunctional polyurethane as claimed in anyone of claims 1-10 wherein said diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid has molecular weight in the range of 800 to 1500, preferably in the range of 1000-1200, wherein said molecular wt. is controlled by the urethane modification, favoring dispersion stability over the shelf life of up to 3 years at varying ambient temperature range of 15 to 40?C, is adapted for infinite MTO (mineral turpentine oil) tolerance, and ensures good drying behavior when employed in alkyd enamel coating formulations.

12. A process of manufacturing multifunctional polyurethane based wetting and dispersing compound as claimed in claims 1-11 comprising the steps of
(i) trans-esterification/ esterification of Oil/fatty acid with select liquid or low melting polyol to obtain trans-esterified/esterified Oil/fatty acid;
(ii) partial reaction of hydroxyl functionality of said trans-esterified/esterifiedoil/ fatty acid with diisocyanate resulting in urethane linkages and obtaining therefrom said multifunctional polyurethane based wetting and dispersing compound.
13. A process as claimed in claim 12 wherein
said step (i) comprises
trans-esterification/esterification of oil/fatty acid preferably Soyabean oil/fatty acid, monomeric linseed oil/fatty acid with at least one or more polyols comprising of Trimethylol propane, 2-methyl-1, 3-propanediol, Neopentyl Glycol, Glycerine in the presence of metal salt catalyst, provide for said trans-esterified/esterified oil /fatty acid with a polyol content in the range of 10-27% of said oil and providing for hydroxyl value of 120-200 (mg KOH/gm);
said step (ii) comprises
partial reaction of said trans-esterified/esterified oil /fatty acid with diisocyanate to result in NCO/OH ratio in the range of 0.10-0.30/1.00 of said generated multifunctional polyurethane based wetting and dispersing compound having free -OH value in the range of 100-180(mg KOH/gm) preferably in the range of 110-140(mg KOH/gm) and iodine value in the range of 100-140 (gmI2/100 gm).

14. Coating formulation comprising
(i) Multifunctional polyurethane based wetting and dispersing compound as claimed in claims 1-11;
(ii) organic and/ or inorganic pigments;
(iii) select air drying alkyd enamels/ paints favoring said coating formulation having therein uniformly dispersed organic and/ or inorganic pigments.
15. Coating formulation as claimed in claim 14 wherein said coating formulation comprises organic and/or inorganic, pigment dispersions having pigment volume concentration in the range of 2-25% in select alkyd based enamels/ paints including long oil air drying alkyd based enamels/ paints effectively dispersed by said multifunctional wetting and dispersing compound present in combination.
16. Coating formulation as claimed in claims 14 or 15 wherein said multifunctional polyurethane based wetting and dispersing compound is employed in the dosage levels of 0.25 %-1.0%, and organic and/or inorganic pigments is employed in the levels of 2-25% Pigment Volume Concentration.
17. Coating formulation as claimed in anyone of claims 14-16 having characteristics of natural as well as accelerated stability at 55?C when kept for at least 30 days involving uniform pigment dispersion devoid of flooding, flotation, settling, and is free of any loss of drying, tinting strength and smooth uniform and glossy appearance.

Dated this the 27th day of February, 2019 Anjan Sen
Of Anjan Sen and Associates
(Applicants Agent)
IN/PA-199
, Description:FIELD OF INVENTION

This present invention deals with the development of Multifunctional polyurethane Wetting and Dispersing compounds for dispersing Organic, Inorganic & Organic/inorganic pigment combinations in alkyd Paints. Presence of high unsaturation imparted by fatty chain necessary for autoxidative cross-linking coupled with urethane linkages ensured that the wetting and dispersing compounds of the present invention positively impacts the drying as it being one of the critical properties of airdrying alkyds enamels. The prepared wetting and dispersing compounds wereexamined in air drying alkyd enamels with Inorganic, Organic and Organic/Inorganic pigment combinations. The resultant paint compositions were subjected to natural as well as accelerated stability at 55?C for 30 days and tested for pigment dispersion and key paint properties like flooding, flotation, settling, viscosity, drying, gloss and tinting strength.

BACKGROUND ART

Wetting and dispersing compounds are important component of Paint formulations. They are not only responsible for wetting and dispersion of pigments but also play a big role in drying, gloss and shelf life of the paint at varying ambient temperatures across geographies.
Most of the wetting compounds have carboxylic and/or amine functionality which impart good wetting and dispersion properties to the variety of pigments, but on the flip side, show adverse effect due to interactions with other coating ingredients resulting in loss of drying, change in viscosityduring accelerated stability study of paint asexamined to ensure its performance during storage /shelf life.Adverse effect of such carboxylic/ amine functionality is also anticipated in certain other performance properties of the paint during its service life which is being investigated. Relevant Prior arts as referred in the literature on this subject are being mentioned here:

Reference is made to US5125974 that discloses an internal release compound for the production of polyurethane and/or polyurea elastomers, to an isocyanate reactive composition containing that release compound wherein release compound is a reaction product of i) a trans ester of a) a polyester derived from a polymerized fatty acid and either neopentyl glycol or 2,2,4-trimethyl-1,3-pentane diol and b) an acetoacetate and ii) an aliphatic Monoisocyanatethus teaching synthesis of polyester followed by transesterification of the polyester with alkyl acetoacetate and further reaction with aliphatic mono isocyanate while also teaching amine as chain extenders, does not suggest any transesterification of oil with polyol followed up by partial reaction of hydroxyl functionality with poly-isocyanate to result in urethane linkages.

CS170373B1 teaches rapidly drying and hardening urethane alkyds of light color, good elasticity, and good adhesion to metal and wood are manufactured when 0.001-0.5% (based on total wt. of components) of organotin compound is used as a catalyst in the esterification, transesterification and additional steps of synthesis in which C14-C20 unsaturated fatty acids or their glycerides are first reacted with C2-8 polyols, then with C3-10 carboxylic acids or their derivatives, and then with diisocyanates in 1-60% inert solvent at NCO/OH ratio 0.7-1.0. 310 parts safflower oil was esterified with 50 parts glycerol in the presence of 0.35 part dibutyltin bis(2-ethylhexyl maleate) at 240° until the product exhibited maximum miscibility in MeOH, and then the product was reacted with 125 parts 2,4-toluene diisocyanate at NCO/OH ratio 0.86 in 324 parts lacquer petroleum at 70-95° until the NCO group concentration was <0.1% to give a urethane alkyd which dried in 50 min and hardened in 24 h when 0.04% Co and 0.3% Pb were added as naphthenates. While no amine groups are indicated in this prior art,esterification reaction of this prior art involves hydroxyl and carboxylic functionality resulting in alkyds which are further reacted with diisocyanate to form urethane alkyd.

GB 938026 discloses hydrophobic pigment pastes of improved flow capacity and wettability are produced by usingas binder the reaction product of a polyisocyanate with the transesterification product of at least 1 fatty acid glyceride and a polyhydric alcohol. Thus, lacquer linseed oil 787 and linseed stand oil 100 of viscosity 30 poises were esterified with pentaerythritol 68 in the presence of Li naphthenate 2 and then reacted with toluene diisocyanate 90 parts. The product (100parts), a viscous oil of viscosity 22 poises, OH no. 69, acid no. 0 and NCO no. 0, gave, onpigmenting with 40 parts carbon black, a viscosity at 22°/2 sec.-1 of 1300 poises comparedwith 6000 poises for a similarly pigmented linseed stand oil, which also gave a considerablyless black printing paste. This prior art discloses hydrophobic pigment paste which employs Lacquer linseed oil, Linseed stand oil and pentaerythritol/ glycerin for transesterification followed by reaction with Aromatic Isocyanate and subsequent preparation of pigment paste.

US 3177167 relates to varnish-type protective coating compositions that are fast-drying, tough, alkali resistant, and adhesive to various surfaces are described. An ester mixture is prepared by trans esterifying a glyceride drying oil with a polyol or directly esterifying the polyol with an unsaturated fatty acid characteristic of the drying oil, the resulting ester mixture containing 1.5-3 free OH groups/ester linkage present and 3-9% of the total free and esterified hydroxyl, groups present are bonded to structural residues of polyether polyols having molecular weight>500. The resulting ester mixture is charged with an org polyisocyanate in an amt. sufficient to contain = 1 isocyanate group per free OH group. This prior art thus relates to varnish coating composition having no free hydroxyls and employs metallic driers.

US005466772A teaches about Emulsifier prepared for water based alkyd dispersion. The Emulsifier was made by reacting Unsaturated isocyanate with unsaturated fatty acid alcohol(Linseed oil fatty acid reacted with Cardura E10 and polyols) or polyalkylene glycol and keeping free ionic group i.e. amino and hydroxyl groups.

US8987374B2 discloses the polyurethane dispersants developed based on Urethane having laterally attached solvent solubilizing side chains of polyether, polyacrylate or polyolefin for dispersions of organic pigments like Blue, black, red and their performance like stability, gloss, fluidity etc.

US3884713 discloses an invention in which the dispersing compound was prepared by isocyanate reaction with phenol and alcohol without the significant portion of amino groups. This is used for deflocculating organic pigments like Blue and Yellow in organic solvents.

US2526718A discloses the effect of the nitrogen containing ligands on the air drying process called “Loss of dry” on storage conditions. Wheeler et al. found the effect of aromatic, primary and secondary amines largely affect the loss of dry than the tertiary and cycloaliphatic amines. Inventors claimed that the manganese salts showed enhance drying in the coatings when added with O-phenanthroline and bipyridine in the paint mixture.

For wetting and dispersion of the Organic pigments such as Azo-compounds, Lake pigments, Phthalocyanine, quinacridone etc.Amine/amide, carboxylic, and dualfunctional additives having carboxylic and amine functionalities are commonly used. However, such additives showedloss of drying, change in viscosity and thixotropic nature due to interactions with key coating ingredients like metallic driers and free functionality of the alkyd medium. Hence there is a need in the art to provide for multifunctional wetting and dispersing compoundthat would be free from carboxylic and amine functionality and such that a small quantity of such compound incorporated in the paint composition would impart good wetting and dispersion properties toa variety of pigments withoutimpacting drying, gloss and viscositydue to the interactions with other coating ingredients during its intended shelf life as would be apparent through accelerated stability studies.

OBJECTS OF THE PRESENT INVENTION

It is thus the primary object of the present invention to provide for multifunctional polyurethane based wetting and dispersing compound suitable for dispersing Organic, Inorganic & Organic/inorganic pigment combinations in alkyd paints.

It is another object of the present invention to provide for said multifunctional polyurethane based wetting and dispersing compound which would not only be responsible for wetting and dispersion of pigments, but also play key role in drying, gloss and shelf life of the paint at varying ambient temperature conditions.

It is yet another object of the present invention to provide for said multifunctional polyurethane based wetting and dispersing compound that would be free from carboxylic/ amine functionality responsible for inferior drying, loss of drying, change in viscosity and thixotropic behavior due to interactions with other coating ingredients during its shelf life.

It is still another object of the present invention to provide for said multifunctional polyurethane based wetting and dispersing compound that would have low molecular weight of the resultant molecule to ensure that the dispersion remains stable over the intended shelf-life.

It is another object of the present invention to provide for a process for the multifunctional polyurethane based wetting and dispersing compound that would minimize flooding and flotation of pigments and would also prevent sedimentation with no adverse effect on drying. It is yet another object of the present invention that such multifunctional wetting and dispersing compoundcontain high renewable and high active contenti.e. =98% Non-volatile Content.

SUMMARY OF THE INVENTION

Thus according to the basic aspect of the present invention there is provided a multifunctional polyurethane based wetting and dispersing compound comprisingdiisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid, said trans-esterified/esterified oil/fatty acid includes a reaction product of oil/fatty acid and select liquid or low melting polyol, adapted for dispersing organic, inorganic pigment and combinations thereof in alkyd paints to thereby achieve high surface activity with variety of pigments.
Preferably, said multifunctional polyurethane favors both polar and non-polar functionalities with large unsaturation and having sufficient polar hydroxy functional groups and urethane linkages being free ofany carboxylic and amine functionality.
According to another preferred aspect of the present invention in said multifunctional polyurethanesaid diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid has enough polar hydroxy functional groups and urethane linkages based on selective levels of NCO/OH ratio of 0.1-0.30/1.00.
More preferably said multifunctional polyurethane is having Iodine value of 100-140 gmI2/100 gm, Hydroxyl value of 100-180 mg KOH/gm, and NCO/OH ratio of 0.10-0.30/1.00.
According to another preferred aspect of the present invention there is provided multifunctional polyurethane wherein said trans-esterified/esterified oil/fatty acid incorporating select liquid or low melting polyol have melting point in the range of 50 to 150?C comprises Trimethylol propane, 2-methyl-1, 3-propanediol, Neopentyl Glycol, Glycerine.
According to yet another preferred aspect of the present invention there is provided said multifunctional polyurethane wherein said trans-esterified/esterified oil/fatty acid preferably incorporates semi-drying/drying oil including Soyabean oil/fatty acid, monomeric linseed oil/fatty acid.
Preferably said multifunctional polyurethane is provided wherein said polyol trans-esterified/esterified semi-drying/drying oil/fatty acid comprises semi-drying/drying oil/fatty acid of iodine value in the range of 125 to 180 (gm I2 /100gms) and incorporated in said polyol trans-esterified/esterified semi-drying/drying oil/fatty acid in the levels of 70-90% preferably 75-85% to provide for resulting Iodine value in the range of 100-140 gm I2/100 gm.
According to another preferred aspect of the present invention there is provided said multifunctional polyurethane wherein said trans-esterified/esterified semi-drying/drying oil/fatty acid has polyol content in the range of 10-27% of said oil/ fatty acid content and having hydroxyl value in the range of 120-200 (mg KOH/gm).
Preferably in said multifunctional polyurethane said diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid is a reaction product of aliphatic/cycloaliphaticdiisocyanate partially reacted to trans-esterified/esterified semi-drying/drying oil/fatty acid incorporating said select polyol, thereby providing for free -OH value of 100-180(mg KOH/gm) of said diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid.
More preferably, in said multifunctional polyurethane said diisocyanate comprises aliphatic/cycloaliphatic diisocyanate including hexamethylene diisocyanate, Isophorone diisocyanate, etc.
According to another preferred aspect of the present invention there is provided said multifunctional polyurethane wherein said diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid has molecular weight in the range of 800 to 1500, preferably in the range of 1000-1200, wherein said molecular wt. is controlled by the urethane modification, favoring dispersion stability over the shelf life of up to 3 years at varying ambient temperature range of 15 to 40?C, is adapted for infinite MTO (mineral turpentine oil) tolerance, and ensures good drying behavior when employed in alkyd enamel coating formulations.

According to another aspect of the present invention there is provided a process of manufacturing multifunctional polyurethane based wetting and dispersing compoundcomprising the steps of
(i) trans-esterification/esterification of Oil/fatty acid with select liquid or low melting polyol to obtain trans-esterified/esterified Oil/fatty acid;
(ii) partial reaction of hydroxyl functionality of said trans-esterified/esterifiedoil/ fatty acid with diisocyanate resulting in urethane linkages and obtaining therefrom said multifunctional polyurethane based wetting and dispersing compound.
Preferably in said process
said step (i) comprises
trans-esterification/esterification of oil/fatty acid preferably Soyabean oil/fatty acid, monomeric linseed oil/fatty acid with at least one or more polyols comprising of Trimethylol propane, 2-methyl-1, 3-propanediol, Neopentyl Glycol, Glycerine in the presence of metal salt catalyst, and to provide for said trans-esterified/esterified oil /fatty acid with a polyol content in the range of 10-27% of said oil and providing for hydroxyl value of 120-200 (mg KOH/gm);
said step (ii) comprises
partial reaction of said trans-esterified/esterified oil /fatty acid with diisocyanate to result in NCO/OH ratio in the range of 0.10-0.30/1.00 of said generated multifunctional polyurethane based wetting and dispersing compound having free -OH value in the range of 100-180(mg KOH/gm) preferably in the range of 110-140(mg KOH/gm) and iodine value in the range of 100-140 (gmI2/100 gm).
According to another aspect of the present invention there is provided a coating formulation comprising
(i) Multifunctional polyurethane based wetting and dispersing compound;
(ii) organic and/ or inorganic pigments;
(iii) select air drying alkyd enamels/ paints favoring said coating formulation having therein uniformly dispersed organic and/ or inorganic pigments.
Preferably said coating formulation comprises organic and/or inorganic, pigment dispersions having pigment volume concentration in the range of 2-25% in select alkyd based enamels/ paints including long oil air drying alkyd based enamels/ paints effectively dispersed by said multifunctional wetting and dispersing compound present in combination.
More preferably in said coating formulationsaid multifunctional polyurethane based wetting and dispersing compound is employed in the dosage levels of 0.25 -1.0%, and organic and/or inorganic pigments is employed in the levels of 2-25% Pigment Volume Concentration.
According to another preferred aspect of the present invention there is provided said coating formulation having characteristics of natural as well as accelerated stability at 55?C when kept for at least 30 days involving uniform pigment dispersion devoid of flooding, flotation, settling, and is free of any loss of drying, tinting strength and smooth uniform and glossy appearance.

DETAILED DESCRIPTION OF THE INVENTION:

As discussed hereinbefore, the present invention provides for multifunctional polyurethane wetting and dispersing compounds applicable for pigment dispersion in alkyd based paints comprising diisocyanate based partial urethane modified trans-esterified/esterified oil/fatty acid, said trans-esterified/ esterified oil/ fatty acid includes a reaction product of oil/fatty acid and select liquid or low melting polyol, adapted for dispersing organic, inorganic pigment and combinations thereof in alkyd paints to thereby achieve high surface activity with variety of pigments.
Saidtransesterification/esterification of liquid and low melting polyols with drying oils or their fatty acids in presence of metal salts as catalyst was carried out to provide for hydroxyl functional fatty esters that were partially reacted with aliphatic/cycloaliphatic diisocyanates to create urethane linkages while maintaining select levels of free hydroxyl functionality. The molecules thus formed are havingalkene, ester, hydroxyl and urethane functionalitiesproviding active sites for wetting and dispersing of pigments in the alkyd medium. Further presence of high unsaturation imparted by fatty chain necessary for autoxidative crosslinking coupled with urethane linkages ensured that the wetting and dispersing molecules of the present invention positively impact the drying as it is one of the critical properties of air drying alkyds enamels, and at the same time efficiently disperses the pigments. The prepared wetting and dispersing compounds wereexamined in air drying alkyd enamels with Inorganic, Organic and Organic/Inorganic pigment combinations. The resultant paint compositions were subjected to natural as well as accelerated stability at 55?C for 30 days and tested for pigment dispersion and key paint properties like flooding, flotation,settling,viscosity,drying, gloss and tinting strength.
In the paint making process, wetting is the process wherein air surrounding the solid pigment /extender particle agglomerates is substituted by the liquid. For the wetting of the pigment, surface tension of the liquid should be less than particles. If surface tension of the liquid is more, then by use of wetting compound, pigment particles are wetted. Wetting is the first step of dispersion wherein solid particle agglomerate are separated and liquid molecules are adsorbed on the surface and oriented in liquid-air interface. After separation of the particles due to wetting, they should be stabilized, otherwise particle-particle association could happen leading to flooding and flotation. Role of the dispersing compound herein is to avoid particle-particle association which can lead to flooding and flotation of the pigment.
Selection of wetting and dispersing compound herein depends on the type of pigment - either Organic or Inorganic or Organic/Inorganic combination. For dispersion of Inorganic pigments, oil modified wetting compounds (Oil Monoglyceride) are preferred in combination with Zn Octoate and Soyalecithin. However, for the dispersion of the Organic and Organic/Inorganic pigments, wetting compound choice is different to avoid flocculation, flooding and sedimentation. For the dispersion of such pigments, amine, acid and urethane based wetting and dispersing compounds are preferred.

As discussed hereinbefore, the present invention provides for multifunctional polyurethane based wetting and dispersing compounds suitable fordispersing diverse kind of pigments i.e. Organic, Inorganic & Organic/inorganic pigment combinations in alkyd paints.

Said multifunctional polyurethane wetting and dispersing compounds are free from carboxylic and amine functionality effective for dispersing Organic, Inorganic & Organic/inorganic pigment combinations in alkyd Paints, wherein said polyurethane based wetting and dispersing compoundcomprises drying oil/ fatty acid reacted with polyols through transesterification/ esterification enabling creation of sufficient polar hydroxy functional groups, which are partially reacted with aliphatic/cycloaliphatic diisocyanates to provide urethane linkages thereby creating a molecule having both polar and nonpolar functionalities with large unsaturation to achieve high surface activity with variety of pigments.

For wetting and dispersion of the organic pigments, amine and carboxylic acid functional wetting and dispersing compounds are used.However, these wetting compounds interfere in the air oxidation process of air-drying alkyd paints due to the presence of amine / acidic groups.

For air drying of alkyd paints, metal driers are required. The metal driers mentioned below are having different role in the air drying.

1) Cobalt Octoate:It acts as a “surface Drier”. Its main purpose is to initiate the air oxidation. Role of the surface drier is to form hydroperoxy linkage to the oil backbone for crosslinking and further breaking it to form oxygen linkage, rate of reaction of cobalt in this context is faster as compared to other surface drier like Manganese and iron.
2) Zirconium Octoate:It acts as a “Through drier”.It is an active cross-linking compound and improves hardness of dried film as well as its adhesions.
3) Calcium Octoate:It is called as “Auxiliary Drier”. Its role is to keep film open for oxygen uptake which will ensure more crosslinking.
Activity of these driers is different in different pigmented system.In case of high pigmented system, air drying process is slower compared to the clear coat systems.This is due to the following phenomenon called “Loss of dry”. Loss of dry can happen due to following reactions:

• Formation of insoluble complexes in the paint formulation
• Hydrolysis of the drier.
• Prolonged storage
• Aromatic amines, aliphatic primary and secondary amines present.
• Poor wetting of the pigments by the Polymers.

In case of the low Iodine value Oil/fatty acidbased alkyds, the wetting of the pigments is poor, resulting in unstable dispersion. This can also lead to Thixotropy.
Also, the poor wetting of the Organic pigment causes the Loss of dry in the paint and further retards on the storage. This phenomenon was predominantly observed in case of amine based wetting compound where Loss of dry is major challenge.
To address the issues as stated above, the wetting and dispersing compoundof the present invention was developed free from any carboxylic and amine functionality. The polymer molecule of the present invention is based on drying oil/ fatty acid with incorporation of a polyol through transesterification/ esterification process to create enough polar hydroxyl functional groups. The hydroxyl functionality was further partially reacted with aliphatic/cyclo-aliphatic diisocyanate to provide urethane linkages thereby creating a molecule having polar / non-polar functionalities with large unsaturation to achieve high surface activity with variety of pigments. The selection of various ingredients resulting in said multifunctional polyurethane wetting and dispersing compoundenabled ensuring good drying behavior in an alkyd paint.

The wetting and dispersing compound of the present invention showed good drying and stability performance as compared to the commercially available wetting and dispersing compounds generally used in alkyd Enamel formulations.Wetting and dispersing compounds of the present invention are based on multifunctional chemistry wherein pigment affinic groups like alkene, ester, urethane and hydroxyl are present. Also, the low molecular weight of the resultant molecule ensures that the dispersion remains stable over the intended shelf life at varying ambient temperature.
Molecular wt. of the said wetting compoundwas possible by way of the present invention to be kept in the range of 800-1500 (Mw), preferably in the range of 1000-1200, the molecular wt. of the wetting compound is controlled by the urethane modification. Purpose of the moderate molecular weight is for the stability of the paints. Lower molecular weighthelps for better dispersion and longer shelf-life. Higher molecular weight leads to over-wetting and this leads to soft sedimentation of the pigment in storage conditions. Use of high molecular weight copolymeric polyurethane based wetting compounds have good dispersion but showed soft settling on storage. Hence lower molecular wt. is preferred.

The developed multifunctional polyurethane molecule provides high unsaturation coupled with urethane and hydroxyl functionalities imparting good wetting and dispersing characteristics of pigments in alkyd paint with desired drying and accelerated stability performance.
Developed wetting compounds mentioned herein were prepared by transesterification/esterification of drying oil/ fatty acid having iodine value in therange of 125-180 gm I2/100 gm with liquid or low melting polyols. Such hydroxy functional fatty esters having hydroxyl value of 120-200 mg KOH/gm were further reacted with aliphatic/cycloaliphatic diisocyanate to get free hydroxyl value 100-180 mg KOH/gm. Oil/ fatty acid used in such compound is in the range of 70-90% preferably 75-85% which provided Iodine value in the range of 100-140 gm I2/100 gm preferably 110-120 gm I2/100 gm. Wetting and dispersing compounds were designed with Hydroxyl value in the range of preferably 100-180 mg KOH/gm providing hydrogen bonding to organic and Inorganic pigments and the urethane linkages provided excellent wetting to the organic pigment. Contrary to the present invention, conventional Amine/carboxylic acid functional wetting and dispersing compounds while provided good wetting to the Organic pigments but showed significant loss of drying.

In the present invention, transesterification / esterification of oil / fatty acid with select polyols having liquid or low melting point in the range of 50 to 150?C is carried out followed by partial reaction of hydroxyl functionality of said trans-esterified oil/ esterified fatty acid with poly-isocyanate where the NCO/OH ratio is in the range of 0.10-0.30/1.00 resulting in urethane functionality with excess hydroxyl functionality.

The present invention is also preferably based on selective employment of Semi-drying/drying oil/fatty acid (different from Lacquered linseed Oil and linseed stand oil) with specific polyols like Trimethylol propane, 2-METHYL-1,3-PROPANEDIOL, Neopentyl Glycol, Glycerin etc.in the range of 10-27% of Oil content resulting in hydroxyl value of 120-200 (mg KOH/gm) which in turn is followed by reaction with aliphatic/cyclo-aliphatic diisocyanateto ensure free OH value in the range of 100-180(mg KOH/gm).

For the purposes of the present invention pentaerythritol, di-pentaerythritol and similar polyols having high melting point beyond the melting point of 150?C are not suitable for trans-esterification/esterification process of the present inventionas such polyols lead to crystallization/ separation at ambient temperature on storage.

The said multifunctional polyurethane based wettingand dispersing compoundof the present invention is developed by first reacting oil/fatty acid with polyol in presence of metal salts as catalyst to result in the hydroxyl functional fatty esterand further reacting this with aliphatic/cyclo-aliphatic diisocyanate. The urethane modification in this is NCO/OH= 0.1-0.30/1.00. Hence, the free hydroxyls are abundant. The hydroxyl functionality along with the Urethane functionality provide wetting of organic pigments through hydrogen bonding.

Thus, the select ingredients when provided in a selective manner enabledachievement of the required select functionalities so that good wetting and dispersion of organic/inorganic pigment, Good Flow/Leveling, Gloss, DOI with avoidance of “loss of dry” due to interactions of driers with wetting and dispersing compound.

The final characteristics of the multifunctional polyurethane wetting & dispersing compound of the present invention are - Iodine value of 100-140 gm I2 /100 gm, Hydroxyl value of 100-180 mg KOH/gm, and the NCO/OH ratio of 0.10-0.30/1.00.

Amine functionality available in conventional wetting and dispersing compounds have tendency to interfere with air drying characteristics. The interaction of amine with metal driers, reduces the electron transfer towards hydroperoxy formation resulting in longer drying time of the final paint. As the said wetting and dispersing compound is free from amine functionality, no retardation in air drying characteristics is observed by using this in Paint formulation. The polar part of the wetting compound of the present invention comprises hydroxyl and urethane functionality. The non-polar part is the unsaturation from the oil/fatty acid.

Also, amine and carboxylic based wetting/dispersing compounds are conventionally used for wetting and dispersion of Organic pigment and Organic/Inorganic pigment combination for air drying alkyd based paints. Improper dispersion of pigments in semi drying oil alkyd based paints may throw up issues likeflooding, floatation and sedimentation on storage and loss of dry. Such issues are largely due to the poor wetting of the organic pigments and in certain cases may require higher dose of wetting/dispersing additives resulting in retarding the drying with this increased dose of such additives.

The solution to the above problem, was also the wetting and dispersing compound of the present invention for paints by eliminating amine and carboxylic functionality. To enhance the wetting capability in absence of amine and carboxylic functionality, functionalities like alkene, ester, urethane and hydroxyl were used, which surprisingly was found to achieve good wetting and dispersing characteristics without impairing consistency and drying of the paint.

Experimentations revealed that select polyols were found to be critical for the trans-esterification/esterification of the present invention. Polyol’s with high melting point like mono Pentaerythritol, Di pentaerythritol showed separation on storage.Polyols like Trimethylol propane, 2-METHYL-1,3-PROPANEDIOL, Neopentyl Glycol, Glycerine etc. having primary hydroxyls and melting point less than 150 ?C showed good stability without any crystallization /separation. It was also found that employing oil having Iodine value in the range of 125 to 180 (gm I2/100gms) showed better dispersion properties and no loss of dry.

Further it was found that employing aromatic Diisocyanate gave haze development in the system and gave yellowing appearance in accelerated weathering when used in Paint formulation.

Further experiments revealed that aliphatic/cyclo-aliphatic diisocyanate at appropriate level gave clear appearance in the wetting compound and better dispersion in paint formulation. The use of aliphatic/cyclo-aliphatic diisocyanate with the combination of the above mentioned polyols and oil/fatty acid gave improved flow and leveling and visual gloss.

The wetting and dispersing compound thus developed after series of experiments with hydroxyl value of 100-180 (mg KOH/gm), Iodine value of 100-140 (gmI2/100 gm) and urethane linkages such as the NCO/OH ratio of 0.10-0.30/1.00 is maintained, showed excellent wetting and dispersion characteristics for alkyd based pigmented coating compositions.While designing such wetting and dispersing compounds, different aliphatic/cycloaliphatic Isocyanate monomers can be used for creating Urethane linkages.
Examples:

Example-1

A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.
Ingredients Parts by Weight
Stage I
Soyabean oil 80.73
Pentaerythritol
Li-stearate 10.0
0.27
Stage II
Isophorone diisocyanate
Mineral Turpentine Oil (MTO)
N-Butanol 7.0
1.5
0.5
Total 100

In stage I, Soyabean oil, Pentaerythritol and Li-stearate were taken in the reaction vessel and heated to temperature of about 240-250°C. After achieving temperature, the reaction mass was maintained for 1 hour and its alcohol solubility in Methanol: ethanol 10:3 mixture was checked. After 2 hoursalcohol solubility was 1:3.0 and reaction was stopped, and cooling applied.
[Note: Alcohol solubility test is the in-process check for transesterification reaction. More the solubility more is the hydroxyl generated from oil. The mixture of 10:3 Methanol: Ethanol prepared to get the solubility in 10 ml cylinder.]
In stage II, stage I reaction mass was cooled to 70-75°C and addition of Isophorone Diisocyanate was started dropwise for 30 minutes interval. After completion of addition, flushing was done with MTO and temperature was raised to 105-110°C. Maintained the temperature for 2-3 hours. After getting viscosity on Gardner Scale in the range of R-S, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass. The reaction mass was cooled and packed.

Example-2:
A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.

Ingredients Parts by Weight
Stage I
Linseed Oil 80.73
Pentaerythritol
Li-stearate 10.0
0.27
Stage II
Isophorone diisocyanate
MTO
N-Butanol 7.0
1.5
0.5
Total 100

In stage I, linseed Oil, pentaerythritol and Li-stearate were taken in the reaction vessel and heated to temperature of about 240-250°C. After achieving temperature, the reaction mass was maintained for 1 hour and its alcohol solubility in Methanol: ethanol 10:3 mixture was checked. Reaction was continued to get alcohol solubility of 1:2.0. After 2 hours alcohol solubility was 1:2.0 and the reaction was stopped, and cooling applied.
In stage II, stage I reaction mass was cooled to 70-75?C and addition of Isophorone Diisocyanate was started dropwise for 30 minutes interval After completion of addition, flushing was done with MTO and temperature was raised to 105-110 Deg C. Maintained the temperature for 2-3 hours. After getting viscosityon Gardner Scale in the range of S-T, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass.The reaction mass was cooled and packed.
Examples 1 and 2 having Pentaerythritol, it was found that the stability of the stage 1 intermediate on storage was inferior. It was observed that on storage settling of unreacted Pentaerythritol at the bottom occurred and after mixing of the same haziness developed in the compound. Hence Pentaerythritol was not the right ingredient.

Example-3:
A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.
Ingredients Parts by Weight
Stage I
Linseed Oil fatty acid 60.97
Trimethylol Propane
Dibutyl tin oxide
Mixed xylene 26.39
0.10
3.54
Stage II
Isophorone diisocyanate
MTO
N-Butanol 7.0
1.5
0.5
Total 100

In stage I, linseed oil fatty acid, trimethylol propane, Dibutyl tin oxide (DBTO) and Mixed xylenewere taken in the reaction vessel and heated to temperature of about 235°C max. The temperature was increased gradually with simultaneous removal of water of reaction. Reaction was continued till the acid value was less than 2 mgKOH/gm. After complete esterification, mixed xylene was stripped out by applying vacuum. 70% of mixed xylene was recovered from the reaction mass. Reaction was stopped, and cooling applied.
In stage II, stage I reaction mass was cooled to 70-75°C and addition of Isophorone Diisocyanate was started dropwise for 30 minutes interval. After completion of addition, flushing was done with MTO and temperature raised to 105-110 Deg C. Maintained the temperature for 2-3 hours. After getting viscosity on Gardner Scalein the range of O-P, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass. Reaction mass was cooled and packed.

Example-4:
A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.
Ingredients Parts by Weight
Stage I
Soyabean Oil 75.96
Trimethylol Propane
Li-stearate 14.76
0.28
Stage II
IsophoroneDiisocyanate
MTO
N-Butanol 7.0
1.5
0.5
Total 100

In stage I, soyabean oil, trimethylol propane and Li-stearate were taken in the reaction vessel and heated to temperature of about 240-250°C. After achieving temperature, the reaction mass was maintained for 1 hour and its alcohol solubility in Methanol: ethanol 10:3 mixture was checked. Reaction was continued to get alcohol solubility of 1:3. After 2 hours, alcohol solubility was 1:3.0 and hence, reaction was stopped, and cooling was applied.
In stage II, stage I reaction mass was cooled to 70-75 Deg C and addition of Isophorone Diisocyanate was started dropwise for 30 minutes interval. After completion of addition, flushing was done with MTO and temperature was raised to 105-110?C. Maintained the temperature for 2-3 hours. After getting viscosityon Gardner Scale of L-M, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass. Reaction mass was cooled and packed.

Example-5:
A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.
Ingredients Parts by Weight
Stage I
Soyabean Oil 77.2
Trimethylol Propane
Li-stearate 15
0.27
Stage II
Toluene Diisocyanate
MTO
N-Butanol 5.53
1.5
0.5
Total 100

In stage I, soyabean oil, trimethylol propane and Li-stearate were taken in the reaction vessel and heated to temperature of about 240-250°C. After achieving temperature, the reaction mass was maintained for 1 hour and its alcohol solubility in Methanol: ethanol 10:3 mixture was checked. Reaction was continued to get alcohol solubility of 1:3. After 2 hours,alcohol solubility was only 1:2.0.Hence, reaction was stopped, and cooling was applied.
In stage II, stage I reaction mass was cooled to 70-75 Deg C and addition oftoluene Diisocyanate was started dropwise for 30 minutes interval. After completion of addition, flushing was done with MTO and temperature was raised to 96-104?C. Maintained the temperature for 3-4 hrs. After getting viscosity on Gardner Scale of P-Q, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass. The reaction mass was cooled and packed.
The compound formed in this example has shown inferior clarity as compared to the Isophorone diisocyanate based compound. As the Toluene diisocyanate being highly reactive, reaction towards free polyol present in the hydroxy functional esterified / trans esterified fatty ester is preferred leading to haze development.

Example-6:
A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.
Ingredients Parts by Weight
Stage I
Linseed Oil 77.2
Trimethylol Propane
Li-stearate 15
0.27
Stage II
Toluene Diisocyanate
MTO
N-Butanol 5.53
1.5
0.5
Total 100

In stage I, linseed oil, trimethylol propane and Li-stearate were taken in the reaction vessel and heated to temperature of about 240-250°C. After achieving temperature,the reaction mass was maintained for 1 hour and its alcohol solubility in Methanol: ethanol 10:3 mixture was checked. Reaction was continued to get alcohol solubility of 1:3. After 2 hours alcohol solubility was only 1:2.0. Hence, reaction was stopped, and cooling was applied.
In stage II, stage I reaction mass was cooled to 70-75 Deg C and addition of Toluene Diisocyanate was started dropwise for 30 minutes interval. After completion of addition, flushing was done with MTO and temperature was raised to 96-104?C. Maintained the temperature for 3-4 hrs. After getting viscosity on Gardner Scale of Q-R, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass. The reaction mass was cooled and discharged.
The compound formed in this example has shown inferior clarity as compared to the Isophorone diisocyanate based compound. As the Toluene diisocyanate being highly reactive, reaction towards free polyol present in the hydroxy functional esterified / trans esterified fatty ester is preferred leading to haze development.

Example-7:
A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.
Ingredients Parts by Weight
Stage I
Linseed Oil 76.4
Trimethylol Propane
DBTO 14.83
0.27
Stage II
Isophorone Diisocyanate
MTO
N-Butanol 6.5
1.5
0.5
Total 100

In stage I, linseed oil, trimethylol propane and dibutyl tin oxide (DBTO) taken in the reaction vessel and heated to temperature of about 240-250°C. After achieving temperature, the reaction mass was maintained for 1 hour and its alcohol solubility in Methanol: ethanol 10:3 mixture was checked. Reaction was continued to get alcohol solubility of 1:3. After 2 hours, solubility of 1:3.0 was achieved and hence, reaction was stopped, and cooling was applied.
In stage II, stage I reaction mass was cooled to 70-75?C and addition of Isophorone diisocyanate was started dropwise for 30 minutes interval. After completion of addition, flushing was done with MTO and temperature was raised to 105-110?C. Maintained the temperature for 2-3 hours. After getting viscosityon Gardner Scale of J-K, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass. Reaction mass was cooled and discharged.

Example-8:
A Multifunctional polyurethane prepared by charging the following constituents into a four-necked reactor flask equipped with a temperature controller, heating mantle, nitrogen purge, overhead stirrer and condenser assembly.
Ingredients Parts by Weight
Stage I
Linseed Oil 75.97
Trimethylol Propane
Li-stearate 14.76
0.27
Stage II
Isophorone Diisocyanate
MTO
N-Butanol 7.0
1.5
0.5
Total 100

In stage I, linseed oil, trimethylol propane and Li-stearate were taken in the reaction vessel and heated to temperature of about 240-250°C. After achieving temperature, the reaction mass was maintained for 1 hour and its alcohol solubility in Methanol: ethanol 10:3 mixture was checked. Reaction was continued to get alcohol solubility of 1:3. After 2 hours, solubility was 1:3 and hence, reaction was stopped, and cooling was applied.
In stage II, stage I reaction mass was cooled to 70-75?C and addition of isophorone diisocyanate was started dropwise for 30 minutes interval. After completion of addition, flushing was done with MTO and temperature was raised to 105-110?C. Maintained the temperature for 2-3 hrs. After getting viscosity on Gardner Scale of L-M, added 0.1-0.5% N-Butanol to quench any free isocyanate remaining in the reaction mass. The reaction mass was cooled and packed.

In the product attained after stage 2, in accordance with the invention such as Examples 3, 4, 7, 8, the NCO/OH ratio of 0.10-0.30/1.00 meaning-NCO equivalent of 0.1-0.30 and -OH equivalent of 1.00 of the wetting and dispersing compound obtained, in said working examples, was maintained to strike the special balance of urethane linkages while keeping excess OH functionality in the range of 100-180(mg KOH/gm) together with unsaturation in the desired range of iodine value in the range of 100 to 140 (gm I2 /100gms), to thereby provide for select polar, non-polar functionalities with large unsaturation of the wetting and dispersing compound enabling high surface activity of the pigment/ effective dispersion of the same in alkyd paints. The aforesaid is demonstrated below under Examples 9-16.

Parameters Example1 Example2 Example3 Example4 Example5 Example6 Example7 Example8
Appearance Hazy Hazy Clear Clear Hazy Hazy Clear Clear
Color on ‘G scale 7-8 6-7 9-10 9-10 10-11 12-13 10-11 10-11
% NVM 97.35 96.8 97.12 96.8 97.62 97.52 97.40 97.50
Viscosity on ‘G’ scale R-S O-P S-T L-M P-Q Q-R J-K L-M
MTO tolerance Infinite Infinite Infinite Infinite Infinite Infinite Infinite Infinite
Weight per liter 0.963 0.963 0.962 0.961 0.961 0.962 0.962 0.961

From the above examples based on stability of the stage 1 and stage 2 intermediate (clear and no separation of polyol) at natural storage conditions, and no haze development,out of the Examples in accordance with the invention of Examples 3, 4, 7, 8, Examples-3 & 8 were selected for further study in coating compositions. Examples 1, 2, 5, 6 not in accordance with the invention could not be proceeded with for dispersing the pigments.

Coating composition of the Top coat:
Wetting & dispersing compounds prepared under Examples- 3 and 8 were tested in the different pigmented paint systems having Pigment Volume Concentration of 2-25%. The designed Wetting & dispersing compounds were tested against conventional amine and carboxylic acid based wetting and dispersing compounds in Organic/Inorganic paint system with long oil alkyds having different compositions as detailed below:

Example 9:
Dispersion was prepared by mixing 100% soyabean oil fatty acid based alkyd(Oil length-54.85%, Theoretical Mol. Wt. 7698), MTO, product prepared in example-3 above, rheology additive, TiO2 - 7.70%, spacer andcopperphthalocyanine bluepigment- 1.5%. The mixture was groundby sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 52-54.This paint was evaluated against conventional amine based wetting and dispersing compound based paint.

Following are the properties of the paint made.
Properties Enamel Paint - based on Soyabean oil fatty acid based alkyd with conventional amine functional wetting and dispersing compound Enamel Paint - based on Soyabean oil fatty acid based alkyd with Multifunctional Polyurethane wetting and dispersing compound (made in Example-3)
Dosage of wetting and dispersing compound 0.5% 0.5%
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dryto touch 180 min 120 min
Tack Free 7 hrs. 35 min hrs. 5 hrs. 40 min
Hard Dry 18 hours 18 hours
Gloss on Uncut Tin Panel - 2 Coats 81-83 80-82
Viscosity on FCB4 at 30 Deg C 96 secs 85 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C) 104 secs 84 secs
Observation after 30 days stability Blue pigment floatation 5% medium separation( no flooding and floatation)

Medium separation and uniform dispersion are the good dispersion properties in respect of easy mixing and avoidance of flooding and flotation. (Medium separation should not be more than 20% of paint volume)

Example 10:
Dispersion was prepared by mixing 100% soyabean oil fatty acid based alkyd (Oil length-57.40%, Theoretical Mol. Wt. 6762), MTO, product prepared in example-8, rheology additive, TiO2 - 7.70%, spacer and copper phthalocyanine blue pigment - 1.5%. The mixture was ground by sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 52-54. This paint was evaluated against conventional acrylic copolymer based polyurethane wetting and dispersing compound based paint.

Following are the properties of the paint made.
Properties Enamel Paint - based on Soyabean oil fatty acid based alkyd with polymeric acrylic PU wetting and dispersing compound Enamel Paint - based on Soyabean oil fatty acid based alkyd with Multifunctional Polyurethane wetting and dispersing compound(made in Example-8)
Dosage of wetting compound 0.5% 0.5%
Finish on Hegmann Gauge 7 7
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dry to touch 120 min 120 min
Tack Free 6 hrs. 55 min 5 hrs. 40 min
Hard Dry O/N O/N
Gloss on Uncut Tin Panel - 2 Coats 83-84 85-86
Viscosity on FCB4 at 30 Deg C 96 secs 96 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C) 102 secs 98 secs
Observation after 30 days stability Blue color floatation 10% medium separation (no flooding
and floatation)

Medium separation and uniform dispersion are considered good dispersion properties in respect of easy mixing and avoidance of flooding and flotation. (Medium separation should not be more than 20% of paint volume)

Example 11:
Dispersion was prepared by mixing 100% soyabean oil fatty acid based alkyd (Oil length-57.40% , Theoretical Mol. Wt. 6762), MTO, product prepared in example-8, rheology additive, TiO2 - 7.70%, spacer and copper phthalocyanine blue pigment - 1.5%. The mixture was ground by sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 52-54. This paint was evaluated against conventional amine based wetting and dispersing compound based paint.
Following are the properties of the paint made.

Properties Enamel Paint - based on Soyabean oil fatty acid based alkyd with conventional amine functional wetting and dispersing compound Enamel Paint - based on Soyabean oil fatty acid based alkyd with Multifunctional Polyurethane wetting and dispersing compound (made in Example-8)
Dosage of wetting compound 0.25% 0.25%
Finish on Hegmann Gauge 7 7
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dry to touch 150 min 120 min
Tack Free 6 hrs. 50 min 5 hrs. 45 min
Hard Dry O/N O/N
Gloss on Uncut Tin Panel - 2 Coats 83-84 85-86
Viscosity on FCB4 at 30 Deg C 92 secs 91 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C) 101 secs 98 secs
Observation after 30 days stability Blue color floatation Uniform dispersion

Example 12:
Dispersion was prepared by mixing 100% soyabean oil fatty acid based alkyd (Oil length-57.40%, Theoretical Mol. Wt. 6762), MTO, product prepared in example-8, rheology additive, TiO2 - 7.70%, spacer and copper phthalocyanine blue pigment - 1.5%. The mixture was ground by sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 52-54. This paint was evaluated against conventional amine based wetting and dispersing compound based paint.

Properties Enamel Paint - based on Soyabean oil fatty acid based alkyd with conventional amine based wetting and dispersing compound Enamel Paint - based on Soyabean oil fatty acid based alkyd with Multifunctional Polyurethane wetting and dispersing compound (made in Example-8)
Dosage of wetting compound 0.75% 0.75%
Finish on Hegmann Gauge 7 7
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dry to touch 150 min 120 min
Tack Free 9 hrs. 30 min. 6 hrs. 10 min
Hard Dry O/N O/N
Gloss on Uncut Tin Panel - 2 Coats 83-84 85-86
Viscosity on FCB4 at 30 Deg C 92 secs 91 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C) 96 secs 95 secs
Observation after 30 days stability Blue color floatation 15% medium separation (no flooding
and floatation)

Example 13:
Dispersion was prepared by mixing 80:20 soyabean oil: dehydrated castor oil based alkyd (Oil length-60.97%, Theoretical Mol. Wt. 12987)MTO, product prepared in example-8, rheology additive, TiO2 - 7.70%, spacer and copper phthalocyanine blue pigment - 1.5%. The mixture was ground by sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 52-54. This paint was evaluated against conventional amine based wetting and dispersing compound based paint.
Following are the properties of the paint made.

Properties Enamel Paint - based on Soyabean oil : dehydrated castor oil 80:20 combination alkyd with conventional amine functional wetting and dispersing compound Enamel Paint - based on Soyabean oil : dehydrated castor oil 80:20 combination alkyd with Multifunctional Polyurethane wetting and dispersing compound(made in Example-8)
Dosage of wetting and dispersing compound 0.5% 0.5%
Finish on Hegmann Gauge 7 7
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dry to touch 180 min 120 min
Tack Free 6 hrs. 55 min 5 hrs. 10 min
Hard Dry O/N O/N
Gloss on Uncut Tin Panel - 2 Coats 83-84 85-86
Viscosity on FCB4 at 30 Deg C 95 secs 95 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C) 108 secs 110 secs
Observation after 30 days stability 15% medium separation (no flooding and floatation)
10% medium separation (no flooding
and floatation)

Example 14:
Dispersion was prepared by mixing 100% soyabean oil fatty acid based alkyd (Oil length-57.40% , Theoretical Mol. Wt. 6762), MTO, product prepared in example 8, rheology additive, TiO2-3.9% and Yellow pigment- 4.85%. The mixture was ground by sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 53-58. This paint was evaluated against conventional amine based wetting and dispersing compound based paint.
Following are the properties of the paint made.
Properties Enamel Paint - based on Soyabean oil fatty acid based alkyd with conventional amine functional wetting and dispersing compound Enamel Paint - based on Soyabean oil fatty acid based alkyd with Multifunctional Polyurethane wetting and dispersing compound (made in Example-8)
Dosage of wetting compound 0.9% 0.9%
Finish on Hegmann Gauge 7 7
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dry to touch 180 min 150 min
Tack Free 6 hrs. 30 min. 5 hrs. 40 min
Hard Dry O/N O/N
Gloss on Uncut Tin Panel - 2 Coats 83-84 82-83
Viscosity on FCB4 at 30 Deg C 85 secs 88 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C) 96 secs 95 secs
Observation after 30 days stability 20% medium separation (no flooding
and floatation)

Uniform dispersion

Example 15:
Dispersion was prepared by mixing 90:10 Soyabean oil: dehydrated castor oil based alkyd (Oil length-61.72%, Theoretical Mol. Wt. 5905), MTO, product prepared in example-8, rheology additive, TiO2 - 3.9% and Yellow pigment - 4.85%. The mixture was ground by sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 53-58. This paint was evaluated against conventional amine based wetting and dispersing compound based paint.
Following are the properties of the paint made.

Properties Enamel Paint - based on Soyabean oil : dehydrated castor oil 90:10 combination alkyd with conventional amine functional wetting and dispersing compound Enamel Paint - based on Soyabean oil : dehydrated castor oil 90:10 combination alkyd with Multifunctional Polyurethane wetting and dispersing compound
(made in Example-8)
Dosage of wetting compound 0.9% 0.9%
Finish on Hegmann Gauge 7 7
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dry to touch 180 min 150 min
Tack Free 8 hrs. 30 min. 6hrs.
Hard Dry O/N O/N
Gloss on Uncut Tin Panel - 2 Coats 83-84 79-81
Viscosity on FCB4 at 30 Deg C 85 secs 88 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C)
96 secs
95 secs
Observation after 30 days stability Uniform dispersion Uniform dispersion

Example 16:
Dispersion was prepared by mixing 90:10 Soyabean oil: dehydrated castor oil based alkyd(Oil length-61.72%, Theoretical Mol. Wt. 5905), MTO, product prepared in example-3, rheology additive, TiO2 - 3.9% and Yellow pigment - 4.85%. The mixture was ground by sand mill process at 1800 rpm speed for 14 minutes to get fineness of grind of 6.5 minimum on Hegmann gauge. After achieving finish, the dispersion was stabilized by adding resin and MTO.
The above formed mill base was thinned with Resin, MTO, Driers and anti-skinning compound. Viscosity of the paint formed was kept in the range of 85-100 secs on the ford cup B4 and %NVM of 53-58. This paint was evaluated against conventional amine based wetting and dispersing compound based paint.
Following are the properties of the paint made.

Properties Enamel Paint - based on Soyabean oil : dehydrated castor oil 90:10 combination alkyd with conventional amine functional wetting and dispersing compound Enamel Paint - based on Soyabean oil : dehydrated castor oil 90:10 combination alkyd with Multifunctional Polyurethane wetting and dispersing compound
(made in Example-3)
Dosage of wetting compound 0.9% 0.9%
Finish on Hegmann Gauge 7 7
Appearance on Panel Smooth, Uniform & Glossy Smooth, Uniform & Glossy
Drying Time @ Hours
Dry to touch 180 min 150 min
Tack Free 8 hrs. 30 min. 6hrs 15 min.
Hard Dry O/N O/N
Gloss on Uncut Tin Panel - 2 Coats 83-84 78-79
Viscosity on FCB4 at 30 Deg C 85 secs 84 secs
Accelerated stability Viscosity after 30 days (on FCB4 at 30 Deg C)
96 secs
91 secs
Observation after 30 days stability Uniform dispersion Uniform dispersion

From the above tables 9-16 it is inferred that medium separation and uniform dispersion while are considered to be good dispersion properties in respect of easy mixing and avoidance of flooding and flotation,especially considering that medium separation should not be more than 20% of paint volume, all the coating compositions of the top coat above possesses stable and good dispersion properties and also have reasonable reduction of time to be dry to touch and always becomes tack free requiring smaller time duration vis-à-vis the same enamel paint involving the conventional amine functional wetting and dispersing compound,as comparative.

In example 9, alkyd used is different than the examples 10 & 11 (involving the same alkyd). In example 11, uniform dispersion was observed as wetting & dispersing is at 0.25% as compared to 0.5% of example 10. Higher dose in example 10 led to over wetting and hence medium separation, but was within the acceptable levels. This was also observed in example 12 where wetting & dispersing compound is at 0.75% dosage. Higher oil length of the alkyd based enamel paint was found to be particularly effective. The above examples also demonstrates the compatibility of the multifunctional polyurethane based wetting and dispersing compound of the present invention to effectively disperse various types of pigments including organic, inorganic or mixtures thereof together with the below mentioned advantages.

It is thus possible for the present advancement to provide for the advantages imparted by the multifunctional polyurethane of the present invention and includes the following:

1. Wetting and dispersing activity with organic / Inorganic pigments
2. Reduced flooding / flotation of pigments
3. Increased Gloss
4. Prevents sedimentation and binder separation
5. No adverse effect on drying
6. High active content (˜ 98% NVM)
7. Economical
This finds end use and application in air drying enamels and primers for decorative and industrial segments.