Rohm and Haas Company

Thomas H Haag

William H Brendley, Jr

Richard Martorano

Disclosed are aqueous acrylic thermosetting resinous compositions having an alkaline pH and containing a specific rheological modifier in critical amount, and application to metal sheets, curing the same, and in a preferred embodiment shaping the metals to achieve metal decoration. By 'decorating' is meant applying synthetic resinous coatings to the metal followed by a mechanical forming operation such as the formation of can bodies or screw-threaded bottle caps. The compositon is thermosettable and comprises (A) a water-insoluble addition copolymer of certain monomers in latex form, (B) a water-soluble urea-formaldehyde or triazine-formaldehyde reaction product or a water-soluble methanol or ethanol ether thereof, or a combination of the aminoplast products, and, as an essential component, (C) a water-soluble polyethylene glycol having an average molecular weight of from about 400 to about 100,000. The copolymer contains small amounts of carboxyl groups, and amide or hydroxyl functionality, or both of the latter. The weight ratio on a solids basis of (A) to (B) is from 35:65 to 65:35, and the solids content is between 40 and 80 percent, the amount of said water-soluble rheology modifier being from 1 to 5 percent based on the total weight of (A) and (B), on a solids basis.

Method of coating utilizing rheologically modified metal decorating and

Disclosed are aqueous acrylic thermosetting resinous compositions having an alkaline pH and containing a specific rheological modifier in critical amount, and application to metal sheets, curing the same, and in a preferred embodiment shaping the metals to achieve metal decoration. By 'decorating' is meant applying synthetic resinous coatings to the metal followed by a mechanical forming operation such as the formation of can bodies or screw-threaded bottle caps. The composition is thermosettable and comprises (A) a water-insoluble addition copolymer of certain monomers in latex form, (B) a water-soluble urea-formaldehyde or triazine-formaldehyde reaction product or a water-soluble methanol or ethanol ether thereof, or a combination of the aminoplast products, and, as an essential component, (C) a water-soluble polyethylene glycol having an average molecular weight of from about 400 to about 100,000. The copolymer contains small amounts of carboxyl groups, and amide or hydroxyl functionality, or both of the latter. The weight ratio on a solids basis of (A) to (B) is from 35:65 to 65:35, and the solids content is between 40 and 80 percent, the amount of said water-soluble rheology modifier being from 1 to 5 percent based on the total weight of (A) and (B), on a solids basis.

Rheologically modified metal decorating and aqueous coating composition

Aqueous resinous compositions having an alkaline pH for application to metal sheets and curing the same prior to shaping the metals to achieve metal decoration are disclosed. By 'decorating' is meant applying synthetic resinous coatings to the metal followed by a severe mechanical forming operation such as the formation of screw-threaded bottle caps. The composition is thermosettable and comprises (A) an addition copolymer of certain monomers and (B) a water-soluble urea-formaldehyde reaction product or a water-soluble methanor or ethanol ether thereof. The copolymer contains small amounts of carboxyl and amide and/or hydroxyl functionality. The weight ratio of (A) to (B) is from 35:65 to 65:35, and the solids content is between 40 and 80 percent. The coating composition has properties which similar previously known aqueous compositions lack, an important one being that the composition may be direct-roller coated onto the substrate without fouling the coating roller with a partially dried accumulation of the coating composition. The coated panels having a wet coating may be placed directly in the curing oven without blistering, avoiding the necessity of a preliminary low temperature drying step and freedom from patterning. The proportions of functional monomers are critical as are the ratios of the addition copolymer to the urea-formaldehyde adduct. Other critical properties are the minimum film-forming temperature (MFT) of the composition which can be no higher than about 15.degree. C. and the glass transition temperature (Tg) of the addition copolymer which must be below 0.degree. C., preferably below -15.degree. C.

Metal decorating method involving mechanical shaping

Aqueous resinous compositions having an alkaline pH for application to metal sheets and curing the same prior to shaping the metals to achieve metal decoration are disclosed. By 'decorating' is meant applying synthetic resinous coatings to the metal followed by a severe mechanical forming operation such as the formation of screw-threaded bottle caps. The composition is thermosettable and comprises (A) an addition copolymer of certain monomers and (B) a water-soluble urea-formaldehyde reaction product or a water-soluble methanol or ethanol ether thereof. The copolymer contains small amounts of carboxyl and amide and/or hydroxyl functionality. The weight ratio of (A) to (B) is from 35:65 to 65:35, and the solids content is between 40 and 80 percent. The coating composition has properties which similar previously known aqueous compositions lack, an important one being that the composition may be direct-roller coated onto the substrate without fouling the coating roller with a partially dried accumulation of the coating composition. The coated panels having a wet coating may be placed directly into the curing oven without blistering, avoiding the necessity of a preliminary low temperature drying step and freedom from patterning. The proportions of functional monomers are critical as are the ratios of the addition copolymer to the urea-formaldehyde adduct. Other critical properties are the minimum film-forming temperature (MFT) of the composition which can be no higher than about 15.degree.C. and the glass transition temperature (Tg) of the addition copolymer which must be below 0.degree. C., preferably below -15.degree. C.

Growing community of inventors

Feasterville, PA, United States of America

Thomas H Haag