Passivation of steel with aqueous amine solutions preparatory to application of non-aqueous protective coatings

Claim 1

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a non-aqueous protective coating containing amine reactive chemical groups, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint scale, rust and the like down to bare metal; b. washing the prepared bare metal surfaces with a concentrated non-toxic and neutralizing aqueous first rinse solution containing only volatile water-soluble amine to rinse out and neutralize any cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said first rinse solution containing essentially no other ingredients that will leave residues on the steel surfaces detrimental to optimum performance and adhesion of subsequently applied non-aqueous protective coatings containing amine reactive chemical groups; said water-soluble amine in solution having a boiling point higher than that of water; c. applying to the steel surfaces a dilute non-toxic aqueous passivating second rinse solution containing only a volatile water-soluble amine having a boiling point higher than that of water to the steel surfaces to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surface is in a slightly alkaline condition to prevent flash rusting; said second rinse solution containing essentially no other ingredients that will leave residues on the steel surfaces detrimental to optimum performance and adhesion of subsequently applied non-aqueous protective coatings containing amine reactive chemical groups; d. drying said steel surfaces to first evaporate and remove all water leaving a thin layer of only moist amine and then continuing the drying process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, thoroughly dry, free of non-volatile and undesirable residues, and ready for application of suitable non-aqueous protective coatings containing amine reactive chemical groups; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed; any minimal residue of an amine remaining on the cleaned steel surfaces after drying being incorporated into the subsequently applied non-aqueous protective coatings by reaction with amine reactive chemical groups contained in said subsequently applied protective coatings without leaving any water-soluble or ionic residues on the surface of the steel so as not to affect the adhesion and performance of the protective coatings.

Claim 2

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a non-aqueous protective coating containing amine reactive chemical groups, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint scale, rust and the like down to bare metal; b. washing the prepared bare metal surfaces with a concentrated non-toxic and neutralizing aqueous first rinse solution containing only volatile water-soluble amine to rinse out and neutralize any cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said first rinse solution containing essentially no other ingredients that will leave residues on the steel surfaces detrimental to optimum performance and adhesion of subsequently applied non-aqueous protective coatings containing amine reactive chemical groups; said water-soluble amine in solution having a boiling point higher than that of water; c. applying to the steel surfaces a dilute non-toxic aqueous passivating second rinse solution containing only a volatile water-soluble amine having a boiling point higher than that of water to the steel surfaces to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surface is in a slightly alkaline condition to prevent flash rusting; said second rinse solution containing essentially no other ingredients that will leave residues on the steel surfaces detrimental to optimum performance and adhesion of subsequently applied non-aqueous protective coatings containing amine reactive chemical groups; d. drying said steel surfaces to first evaporate and remove all water leaving a thin layer of only moist amine and then continuing the drying process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, thoroughly dry, free of non-volatile and undesirable residues, and ready for application of suitable non-aqueous protective coatings containing amine reactive chemical groups; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed; any minimal residue of an amine remaining on the cleaned steel surfaces after drying being incorporated into the subsequently applied non-aqueous protective coatings by reaction with amine reactive chemical groups contained in said subsequently applied protective coatings without leaving any water-soluble or ionic residues on the surface of the steel so as not to affect the adhesion and performance of the protective coatings.

Claim 18

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a non-aqueous solvent-based protective coating, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint scale, rust and the like down to bare metal; b. washing the prepared bare metal surfaces with a concentrated non-toxic and neutralizing aqueous first rinse solution containing only volatile water-soluble amine to rinse out and neutralize any cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said water-soluble amine in solution having a boiling point higher than that of water; said first rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to optimum performance and adhesion of subsequently applied non-aqueous solvent-based protective coatings; c. applying a dilute non-toxic aqueous passivating second rinse solution containing only a volatile water-soluble amine having a boiling point higher than that of water to the steel surfaces to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surfaces is in a slightly alkaline condition to prevent flash rusting; said second rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimentral to optimum performance and adhesion of subsequently applied non-aqueous solvent-based protective coatings; d. drying said steel surfaces to first evaporate and remove all water leaving a thin layer of only moist amine and then continuing the dry process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, dry, free of non-volatile and undesirable residues, and ready for application of the non-aqueous solvent-based protective coatings; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed; any minimal residue of an amine remaining on the cleaned steel surfaces after drying beng incorporated into the subsequently applied non-aqueous solvent-based protective coating without leaving any water-soluble or ionic residues on the surface of the steel so as not to affect the adhesion and performance of the protective coatings by being dissolved therein as a plasticizer which is later evaporated.

Claim 19

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a non-aqueous solvent-based protective coating, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint scale, rust and the like down to bare metal; b. washing the prepared bare metal surfaces with a concentrated non-toxic and neutralizing aqueous first rinse solution containing only volatile water-soluble amine to rinse out and neutralize any cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said water-soluble amine in solution having a boiling point higher than that of water; said first rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to optimum performance and adhesion of subsequently applied non-aqueous solvent-based protective coatings; c. applying a dilute non-toxic aqueous passivating second rinse solution containing only a volatile water-soluble amine having a boiling point higher than that of water to the steel surfaces to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surfaces is in a slightly alkaline condition to prevent flash rusting; said second rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimentral to optimum performance and adhesion of subsequently applied non-aqueous solvent-based protective coatings; d. drying said steel surfaces to first evaporate and remove all water leaving a thin layer of only moist amine and then continuing the dry process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, dry, free of non-volatile and undesirable residues, and ready for application of the non-aqueous solvent-based protective coatings; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed; any minimal residue of an amine remaining on the cleaned steel surfaces after drying beng incorporated into the subsequently applied non-aqueous solvent-based protective coating without leaving any water-soluble or ionic residues on the surface of the steel so as not to affect the adhesion and performance of the protective coatings by being dissolved therein as a plasticizer which is later evaporated.

Claim 31

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a protective non-aqueous solvent-based coating, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint, scale, rust and the like down to bare metal with a cleaning solution comprising a 5 to 10 percent citric acid solution adjusted to a pH of about 3.5 applied at approximately 160 degrees F.; b. washing the prepared bare metal surfaces with a first rinse of non-toxic neutralizing aqueous solution of approximately 3 percent volatile water-soluble triethanolamine to rinse out and neutralize any cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said triethanolamine in solution having a boiling point higher than that of water; said first rinse solution containing essentially no other ingredients that may leave residue on the steel surfaces detrimental to optimum adhesion and performance of the subsequently applied non-aqueous solvent-based protective coating; c. applying a non-toxic aqueous passivating second rinse solution of approxiately 1 percent volatile water-soluble triethanolamine at a temperature range of approximately 20 to 70 degrees C. to the steel surfaces to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surfaces is in a slightly alkaline condition to prevent rusting; said second rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to optimum adherance and performance of the subsequently applied non-aqueous solvent-based protective coating; d. drying said steel surfaces to first evaporate and remove all water leaving only a thin layer of moist amine; continuing the drying process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, dry, free of non-volatile and undesirable residue and ready for application of non-aqueous solvent-based protective coatings; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed and any minimal residue of triethanolamine remaining on the dry, cleaned steel surfaces being dissolved and incorporated into the subsequently applied non-aqueous solvent-based protective coating and not affecting the adhesion and preformance of the protective coating.

Claim 32

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a protective non-aqueous solvent-based coating, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint, scale, rust and the like down to bare metal with a cleaning solution comprising a 5 to 10 percent citric acid solution adjusted to a pH of about 3.5 applied at approximately 160 degrees F.; b. washing the prepared bare metal surfaces with a first rinse of non-toxic neutralizing aqueous solution of approximately 3 percent volatile water-soluble triethanolamine to rinse out and neutralize any cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said triethanolamine in solution having a boiling point higher than that of water; said first rinse solution containing essentially no other ingredients that may leave residue on the steel surfaces detrimental to optimum adhesion and performance of the subsequently applied non-aqueous solvent-based protective coating; c. applying a non-toxic aqueous passivating second rinse solution of approxiately 1 percent volatile water-soluble triethanolamine at a temperature range of approximately 20 to 70 degrees C. to the steel surfaces to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surfaces is in a slightly alkaline condition to prevent rusting; said second rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to optimum adherance and performance of the subsequently applied non-aqueous solvent-based protective coating; d. drying said steel surfaces to first evaporate and remove all water leaving only a thin layer of moist amine; continuing the drying process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, dry, free of non-volatile and undesirable residue and ready for application of non-aqueous solvent-based protective coatings; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed and any minimal residue of triethanolamine remaining on the dry, cleaned steel surfaces being dissolved and incorporated into the subsequently applied non-aqueous solvent-based protective coating and not affecting the adhesion and preformance of the protective coating.

Claim 33

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a non-aqueous protective coating, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint scale, rust and the like down to bare metal; b. treating the prepared bare metal surfaces with a concentrated non-toxic and neutralizing aqueous first rinse solution containing only volatile water-soluble amine, said water-soluble amine in solution having a boiling point higher than that of water to rinse out and neutralize any acid and other cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said first rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to the optimum adherance and performance of the subsequently applied non-aqueous protective coating; c. subsequently treating the steel surfaces with a dilue non-toxic aqueous passivating second rinse solution containing only a volatile water-soluble amine, having a boiling point higher than that of water, to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surfaces is in a slightly alkaline condition to prevent flash rusting; said second rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to the adherance and performance of the subsequently applied non-aqueous protective coating; d. drying said steel surfaces to first evaporate and remove all water leaving a thin layer of only moist amine and then continuing the drying process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, thoroughly dry, free of non-volatile and undesirable residues, and ready for subsequent application of suitable non-aqueous protective coatings; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed; e. subsequently applying a suitable non-aqueous protective coating to said prepared steel surfaces; any minimal residue of an amine remaining on the cleaned steel surfaces after drying being incorporated into the subsequently applied non-aqueous protective coatings without leaving any water-soluble or ionic residues on the surfaces of the steel so as not to affect the adhesion and performance of the protective coatings.

Claim 34

A method for the treatment and passivation of steel surfaces exposed to the atmosphere to prevent flash rusting during the cleaning and subsequent coating thereof with a non-aqueous protective coating, comprising the steps of: a. initially preparing the steel surfaces to be treated by cleaning and removing grease, paint scale, rust and the like down to bare metal; b. treating the prepared bare metal surfaces with a concentrated non-toxic and neutralizing aqueous first rinse solution containing only volatile water-soluble amine, said water-soluble amine in solution having a boiling point higher than that of water to rinse out and neutralize any acid and other cleaning ingredients remaining on the steel surfaces from the initial preparation thereof; said first rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to the optimum adherance and performance of the subsequently applied non-aqueous protective coating; c. subsequently treating the steel surfaces with a dilue non-toxic aqueous passivating second rinse solution containing only a volatile water-soluble amine, having a boiling point higher than that of water, to ensure that the steel surfaces are essentially free of residue and that any moisture remaining on the steel surfaces is in a slightly alkaline condition to prevent flash rusting; said second rinse solution containing essentially no other ingredients that may leave residues on the steel surfaces detrimental to the adherance and performance of the subsequently applied non-aqueous protective coating; d. drying said steel surfaces to first evaporate and remove all water leaving a thin layer of only moist amine and then continuing the drying process to evaporate essentially all of the volatile water-soluble amine to leave the surfaces clean, thoroughly dry, free of non-volatile and undesirable residues, and ready for subsequent application of suitable non-aqueous protective coatings; said steel surfaces remaining slightly alkaline until all moisture and amine have been removed; e. subsequently applying a suitable non-aqueous protective coating to said prepared steel surfaces; any minimal residue of an amine remaining on the cleaned steel surfaces after drying being incorporated into the subsequently applied non-aqueous protective coatings without leaving any water-soluble or ionic residues on the surfaces of the steel so as not to affect the adhesion and performance of the protective coatings.