초록 ▼

The present invention provides a composition for use in forming a white porcelain enamel coating on aluminized or galvanized steel. The composition according to the present invention includes a solids portion including a glass component and a white pigment. The glass component includes one or more g

The present invention provides a composition for use in forming a white porcelain enamel coating on aluminized or galvanized steel. The composition according to the present invention includes a solids portion including a glass component and a white pigment. The glass component includes one or more glass frits including by weight from about 30% to 50% P2O5,from about 15% to about 30% Al2O3,from about 8% to about 40% X2O where X=Na and/or K, up to about 30% TiO2,up to about 12% B2O3,up to about 10% K2O, up to about 10% ZnO, up to about 8% SiO2,up to about 7% La2O3,up to about 5% Li2O, and up to about 15% F. The white pigment include TiO2. The present invention also provides a method of forming a white porcelain enamel coating on an aluminized or galvanized steel substrate that includes providing a steel substrate having an aluminized or galvanized surface, providing a composition for use in forming a white porcelain enamel coating as previously described, applying the composition to the aluminized or galvanized surface, and firing the composition to form a white porcelain enamel coating. And, the present invention also provides a section of aluminized or galvanized steel having a white porcelain enamel coating disposed thereon, with the white porcelain enamel coating exhibiting an acid resistance of AA or better according to ISO 2722, a class 1 bond adherence rating according to EN 12209, and an opacity of L≥94 according to the CIE L*a*b* uniform color space, where L*=116 (Y/Y0)1/2-16 for Y/Y0) 0.008856.

대표청구항 ▼

1. A composition for use in forming a white porcelain enamel coating on aluminized or galvanized steel, said composition comprising a solids portion comprising a glass component and a white pigment, said glass component comprising one or more glass frits comprising by weight from about 30.6% to 45.9

1. A composition for use in forming a white porcelain enamel coating on aluminized or galvanized steel, said composition comprising a solids portion comprising a glass component and a white pigment, said glass component comprising one or more glass frits comprising by weight from about 30.6% to 45.9% P2O5,from about 19.1% to about 28.7% Al2O3,from about 13.9% to about 20.8% Na2O, from about 4.1% to about 6.1% B2O3,from about 3.4% to about 5.1% K2O, from about 2.3% to about 3.4% ZnO, from about 1.8% to about 2.7% SiO2,from about 1.0% to about 1.5% Li2O, and from about 4.5% to about 6.8% F, and said white pigment comprising TiO2. 2. The composition according to claim 1 further comprising La2O3and LiF as mill additions. 3. The composition according to claim 2 comprising from about 80 to 120 parts by weight of said first glass frit, from about 24 to about 36 parts by weight TiO2,from about 4 to about 6 parts by weight La2O3,and from about 0.4 to about 0.6 parts by weight LiF. 4. The composition according to claim 1, wherein said glass component comprises at least about 65% by weight of said solids portion. 5. The composition according to claim 1 further comprising one or more mill additions selected from the group consisting of KOH, NaGH, sodium metasilicate, La2O3,LiF, WO3,MoO3,ZnS, H3BO3,sodium silicate, K2CO3,and mixtures of the foregoing. 6. The composition according to claim 1, wherein said solids portion is milled to a fineness of less than about 5 cc being retained from a 50 cc sample on a 400 mesh sieve. 7. The composition according to claim 1 wherein said glass component further comprises one or more selected from the group consisting of MoO3,SnO2,CeO2,BaO, MgO, SrO, and Bi2O3. 8. The composition according to claim 1 further comprising a vehicle. 9. The composition according to claim 8 wherein said vehicle comprises water.