Supercritical fluids as diluents in liquid spray application of coatings

Claim 2

The process of Claim 1 wherein the viscosity of the mixture of (a) and (b) is less than about 150 cps.

Claim 3

The process of Claim 1 wherein the viscosity of the mixture of (a) and (b) ranges from about 10 to about 100 cps.

Claim 4

The process of Claim 3 wherein the mixture of (a) and (b) ranges from about 20 to about 50 cps.

Claim 5

The process of Claim 1 further comprising prior to step (2), heating said liquid mixture to a temperature sufficient to prevent the adverse effect caused by rapid cooling when said liquid mixture is sprayed.

Claim 6

The process of Claim 1 further comprising adding to said liquid mixture at least one active solvent (c) in which said at least one polymeric compound (a) is soluble and which is at least partially miscible with the supercritical fluid (b), said solvent being present in an amount such that the viscosity of (a) and (c) is greater than about 150 cps.

Claim 7

The process of Claim 1 wherein the at least one supercritical fluid comprises supercritical carbon dioxide.

Claim 8

The process of Claim 6 wherein the at least one supercritical fluid comprises supercritical carbon dioxide fluid.

Claim 9

The process of Claim 6 wherein the viscosity of the mixture of (a), (b) and (c) is less than about 150 cps.

Claim 10

The process of Claim 9 wherein the viscosity of the mixture of (a), (b) and (c) ranges from about 10 to about 100 cps.

Claim 11

The process of Claim 9 wherein the mixture of (a), (b) and (c) ranges from about 20 to about 50 cps.

Claim 12

The process of Claim 1 wherein said at least one polymeric compound is selected from the group consisting of enamels, varnishes, alkyl resins, polyesters, polyurethanes, cellulosic esters, lacquers and mixtures thereof.

Claim 13

The process of Claim 6 wherein said at least one active solvent is selected from the group consisting of unsaturated or aromatic hydrocarbons, ketones, esters, ethers, alcohols and mixtures thereof.

Claim 14

The process of Claim 13 wherein said active solvent is a glycol ether.

Claim 15

The process of Claim 1 wherein the substrate is selected from the group consisting of metal, wood, glass, ceramic and plastic.

Claim 16

The process of Claim 1 further comprising curing the liquid coating on the substrate.

Claim 17

A process for the liquid spray application of coatings to a substrate, which comprises: (1) forming a liquid mixture in a closed system, said liquid mixture comprising : (a) at least one polymeric compound capable of forming a coating on a substrate; (b) at least one supercritical fluid, in at least an amount which when added to (a) and (c) is sufficient to render the viscosity of said mixture to a point suitable for spray application; and (c) at least one one active solvent in which said polymeric compound is soluble and which is at least partially miscible with the supercritical fluid (b), said solvent being present in an amount such that the viscosity of (a) and (c) is greater than that desirable for liquid spray applications; and (2) spraying said liquid mixture onto a substrate to form a liquid coating thereon.

Claim 18

The process of Claim 17 wherein the viscosity of the mixture of (a), (b) and (c) is less than about 150 cps.

Claim 19

The process of Claim 18 wherein the viscosity of the mixture of (a), (b) and (c) ranges from about 10 to about 100 cps.

Claim 20

The process of Claim 19 wherein the viscosity of the mixture of (a), (b) and (c) ranges from about 20 to about 50 cps.

Claim 21

The process of Claim 17 further comprising prior to step (2), heating said liquid mixture to a temperature sufficient to prevent the adverse effect caused by rapid cooling when said liquid mixture is sprayed.

Claim 22

The process of Claim 17 wherein the at least one supercritical fluid comprises supercritical carbon dioxide fluid.

Claim 23

The process of Claim 22 wherein the viscosity of the mixture of (a), (b) and (c) is less than about 150 cps.

Claim 24

The process of Claim 22 wherein the viscosity of the mixture of (a), (b) and (c) ranges from about 10 to about 100 cps.

Claim 25

The process of Claim 24 wherein the viscosity of the mixture of (a), (b) and (c) ranges from about 20 to about 50 cps.

Claim 26

The process of Claim 22 further comprising prior to step (2), heating said liquid mixture to a temperature sufficient to prevent the adverse effect caused by rapid cooling when said liquid mixture is sprayed.

Claim 27

The process of Claim 17 wherein said at least one polymeric compound is selected from the group consisting of enamels, varnishes, alkyl resins, polyesters, polyurethanes, cellulosic esters, lacquers and mixtures thereof.

Claim 28

The process of Claim 17 wherein said at least one active solvent is selected from the group consisting of unsaturated or aromatic hydrocarbons, ketones, esters, ethers, alcohols and mixtures thereof.

Claim 29

The process of Claim 28 wherein said active solvent is a glycol ether.

Claim 30

The process of Claim 17 wherein the substrate is selected from the group consisting of metal, wood, glass, ceramic and plastic.

Claim 31

The process of Claim 17 further comprising curing the liquid coating on the substrate.

Claim 32

A process for the liquid spray application of coatings to a substrate, which comprises: (1) forming a liquid mixture in a closed system of: (a) at least one polymeric compound capable of forming a coating on a substrate; (b) at least one supercritical fluid carbon dioxide, in at least an amount which when added to (a) and (c) is sufficient to render the viscosity of said mixture to a point suitable for spray application; and (c) one active solvent in which said polymeric compound is soluble and which is at least partially miscible with supercritical fluid carbon dioxide, said solvent being present in an amount such that the viscosity of (a) and (c) is greater than that desirable for liquid spray applications; and (2) spraying said liquid mixture onto a substrate to form a liquid coating thereon.

Claim 33

The process of Claim 32 wherein the viscosity of the mixture of (a), (b) and (c) is less than about 150 cps.

Claim 34

The process of Claim 33 wherein the viscosity of the mixture of (a), (b) and (c) ranges from about 10 to about 100 cps.

Claim 35

The process of Claim 34 wherein the mixture of (a), (b) and (c) ranges from about 20 to about 50 cps.

Claim 36

The process of Claim 32 further comprising prior to step (2), heating said liquid mixture to a temperature sufficient to prevent the adverse effects caused by rapid cooling when said liquid mixture is sprayed.

Claim 37

The process of Claim 32 wherein said at least one polymeric compound is selected from the group consisting of enamels, varnishes, alkyl resins, polyesters, polyurethanes, cellulosic esters, lacquers and mixtures thereof.

Claim 38

The process of Claim 32 wherein said at least one active solvent is selected from the group consisting of unsaturated or aromatic hydrocarbons, ketones, esters, ethers, alcohols and mixtures thereof.

Claim 39

The process of Claim 38 wherein said at least one active solvent comprises a glycol ether.

Claim 40

The process of Claim 32 wherein the substrate is selected from the group consisting of metal, wood, glass, ceramic and plastic.

Claim 41

The process of Claim 32 further comprising curing the liquid coating on the substrate.

Claim 42

A process for the liquid spray application of coatings to a substrate wherein the use of environmentally undesirable organic solvents is minimized, which comprises: (1) forming a liquid mixture in a closed system of: (a) at least one polymeric compound capable of forming a coating on a substrate said polymeric compound being present in an amount ranging from about 5 to about 65 wt.% based upon the total weight of (a), (b) and (c); (b) supercritical carbon dioxide fluid, in at least an amount which when added to (a) and (c) is sufficient to render the viscosity of said mixture of (a), (b) and (c) to a point ranging from about 10 to about 100 cps.; and (c) at least one active solvent in which said polymeric compound is soluble and which is at least partially miscible with supercritical carbon dioxide fluid, said solvent being present in an amount up to about 70 wt.% based upon the total weight of (a), (b), and (c) such that the viscosity of the mixture of (a) and (c) has a viscosity greater than about 150 cps.; and (2) spraying said liquid mixture onto a substrate to form a liquid coating thereon.

Claim 43

The process of Claim 42 wherein the polymeric compound is present in amounts ranging from about 15 to about 55 wt. % based upon the total weight of (a), (b) and (c).

Claim 44

The process of Claim 42 wherein the at least one active solvent is present in amounts ranging from about 5 to about 50 weight % based upon the total weight of (a), (b) and (c).

Claim 45

The process of Claim 42 wherein the supercritical carbon dioxide fluid is present in amounts ranging from about 10 to about 60 weight % based upon the total weight of (a), (b) and (c).

Claim 46

The process of Claim 42 wherein the supercritical carbon dioxide fluid is present in amounts ranging from about 20 to 60 weight %, based upon the total weight of (a), (b) and (c).

Claim 47

The process of Claim 42 wherein said polymeric compound is selected from the group consisting of enamels, varnishes, alkyl resins, polyesters, polyurethanes, cellulosic esters, lacquers and mixtures thereof.

Claim 48

The process of Claim 42 wherein said at least one active solvent is selected from the group consisting of unsaturated or aromatic hydrocarbons, ketones, esters, ethers, alcohols and mixtures thereof.

Claim 49

The process of Claim 48 wherein said active solvent is a glycol ether.

Claim 50

The process of Claim 42 wherein the substrate is selected from the group consisting of metal, wood, glass, ceramic and plastic.

Claim 51

The process of Claim 42 further comprising curing the liquid coating on the substrate

Claim 53

The apparatus of Claim 52 further comprising (6) means for heating any of said components and/or said liquid mixture of components.