A substrate for flexible device. The substrate has a nickel-plated metal sheet having a nickel-plating layer formed on at least one surface of a metal sheet or a nickel-based sheet, and a glass layer of an electrically-insulating layered bismuth-based glass on a surface of the nickel-plating layer or the nickel-based sheet. An oxide layer having a roughened surface is formed on the surface of the nickel-plating layer or the surface of the nickel-based sheet, and the bismuth-based glass contains 70 to 84% by weight of Bi.sub.2O.sub.3, 10 to 12% by weight of ZnO, and 6 to 12% by weight of B.sub.2O.sub.3. Also disclosed is a method for producing the substrate for flexible device, a substrate for an organic EL device, a sheet used as a substrate for flexible device, a method for producing the sheet and a bismuth-based lead-free glass composition.

A bismuth-based lead-free glass composition containing 70 to 84% by weight of Bi.sub.2O.sub.3, 10 to 12% by weight of ZnO, and 6 to 12% by weight of B.sub.2O.sub.3.

An enamel composition, a method for preparing an enamel composition, and a cooking appliance are provided. The enamel composition may include phosphorus pentoxide (P.sub.2O.sub.5) at 15 to 50 wt %; silicon dioxide (SiO.sub.2) at 10 to 20 wt %; boron oxide (B.sub.2O.sub.3) at 1 to 15 wt %; one or more of lithium oxide (Li.sub.2O), sodium oxide (Na.sub.2O), or potassium oxide (K.sub.2O) at 5 to 20 wt %; one or more of sodium fluoride (NaF), calcium fluoride (CaF.sub.2), or aluminum fluoride (AlF.sub.3) at 1 to 5 wt %; one or more of magnesium oxide (MgO), barium oxide (BaO), or calcium oxide (CaO) at 1 to 35 wt %; and one or more of titanium dioxide (TiO.sub.2), cerium dioxide (CeO.sub.2), molybdenum trioxide (MoO.sub.3), bismuth oxide (Bi.sub.2O.sub.3), or copper oxide (CuO) at 10 to 25 wt %, such that a heating time required for cleaning may be shortened and oil contaminants may be completely removed.

An enamel composition for a cooking appliance is prepared by a preparation method. The enamel composition includes glass frits, a siloxane-based compound, a silane-based compound, and mill addition. The mill addition includes one or more materials selected from a group comprised of SiO.sub.2, Al.sub.2O.sub.3, ZrO.sub.2, and TiO.sub.2, thereby suppressing defects such as chipping even when the enamel composition is used at high temperature, for pyrolysis of contaminants.

A ground coat enamel composition for production of an adhesion promoter layer between steel and at least one cover coat enamel for production of an enamel-based coating that is highly corrosion-resistant with respect to mechanical, thermal and chemical effects. The ground coat enamel composition includes boron oxide (B.sub.2O.sub.3) and alkali metal oxide(s), especially Li.sub.2O, Na.sub.2O and/or K.sub.2O, in percentage proportions by weight: a first main constituent, SiO.sub.2 from 35-70%, preferably 40-65%, and, as a second main constituent, from Fe.sub.2O.sub.3 5-28%, preferably in the range from 7-23% and particularly 8%-15% by weight. Also disclosed is a ground coat enamel layer produced from such a ground coat enamel composition. A highly corrosion-resistant article having such a ground coat enamel layer. A method for producing such a ground coat enamel layer and also a method for producing a highly corrosion-resistant article using such a ground coat enamel composition.

There is disclosed a novel enamel composition that may be applied to all diverse components for a cooking appliance, with excellent cleaning performance and adhesion. The enamel composition of the present disclosure may include 10 to 25% by weight of SiO.sub.2, 15 to 30% by weight of P.sub.2O.sub.5, 1 to 15% by weight of B.sub.2O.sub.3, 10 to 25% of at least one of Na.sub.2O, Li.sub.2O and K.sub.2O, 1 to 5% by weight of NaF, 15 to 35% by weight of at least one of Al.sub.2O.sub.3, TiO.sub.2 and ZrO.sub.2, and 1 to 10% by weight of at least one of Fe.sub.2O.sub.3, Co.sub.3O.sub.4 and NiO, thereby being applicable to coating of components for a cooking appliance such as a burner cap, a grate and a griddle in which food is vulnerable to contamination and subject to thermal shock.

An enamel composition, a method for preparing an enamel composition, and a cooking appliance are provided. The enamel composition may include 15 to 50 wt % of phosphorus pentoxide (P.sub.2O.sub.5); 5 to 20 wt % of one or more of lithium oxide (Li.sub.2O), sodium oxide (Na.sub.2O), or potassium oxide (K.sub.2O); 1 to 5 wt % of one or more of sodium fluoride (NaF), calcium fluoride (CaF.sub.2), or aluminum fluoride (AlF.sub.3); 1 to 35 wt % of one or more of magnesium oxide (MgO), barium oxide (BaO), or calcium oxide (CaO); and 5 to 30 wt % of one or more of manganese dioxide (MnO.sub.2), molybdenum trioxide (MoO.sub.3), bismuth oxide (Bi.sub.2O.sub.3), or nickel oxide (NiO). The enamel composition may be cleaned without being putting it into water.

An enamel composition, a method for preparing an enamel composition, and a cooking appliance are provided. The enamel composition may include 15 to 50 wt % of phosphorus pentoxide (P.sub.2O.sub.5); 1 to 20 wt % of silicon dioxide (SiO.sub.2); 1 to 20 wt % of boron oxide (B.sub.2O.sub.3); 5 to 20 wt % of one or more of lithium superoxide (Li.sub.2O), sodium oxide (Na.sub.2O), or potassium oxide (K.sub.2O); 1 to 5 wt % of one or more of sodium fluoride (NaF), calcium fluoride (CaF.sub.2), or aluminum fluoride (AlF.sub.3); 1 to 35 wt % of one or more of magnesium oxide (MgO), barium oxide (BaO), or calcium oxide (CaO); and 5 to 30 wt % of one or more of titanium dioxide (TiO.sub.2), vanadium pentoxide (V.sub.2O.sub.5), molybdenum trioxide (MoO.sub.3), or iron oxide (Fe.sub.2O.sub.3). With such an enamel composition, cleaning may be performed at a low temperature for thermal decomposition, and contaminants, such as fat, may be more completely removed.

An enamel composition, a method for preparing an enamel composition, and a cooking appliance are provided. The enamel composition may include 20 to 50% by weight of silicon dioxide (SiO.sub.2), 7 to 12% by weight of boron oxide (B.sub.2O.sub.3), one or more of lithium superoxide (Li.sub.2O), sodium oxide (Na.sub.2O), or potassium oxide (K.sub.2O), and 10 to 20% by weight of sodium fluoride (NaF), 1 to 10% by weight of zinc oxide (ZnO), and one or more of molybdenum oxide (MoO.sub.3), bismuth oxide (Bi.sub.2O.sub.3), or cerium dioxide (CeO.sub.2), and 10 to 40% by weight of titanium dioxide (TiO.sub.2). With such an enamel composition, cleaning is possible in a heating condition of a relatively low temperature and without a soaking process using water.

A glass composition, a cooking appliance having a glass composition, and a method of forming a glass composition may include a glass frit including 15 wt. % to 50 wt. % silicon dioxide (SiO.sub.2), 10 wt. % to 30 wt. % of diboron trioxide (B.sub.2O.sub.3), 5 wt. % to 35 wt. % of zinc oxide (ZnO), and 10 wt. % to 30 wt. % of an I-group oxide. The glass frit may further include at least one of aluminum oxide (Al.sub.2O.sub.3), zirconium dioxide (ZrO.sub.2), or titanium dioxide (TiO.sub.2) by about 0.1 wt. % to 5 wt. %; at least one of sodium fluoride (NaF) or aluminum trifluoride (AlF.sub.3) by about 1 wt. % to 5 wt. %; and at least one of cobalt(II) dicobalt(III) oxide (Co.sub.3O.sub.4), nickel(II) oxide (NiO), iron(III) oxide (Fe.sub.2O.sub.3), or manganese(IV) oxide (MnO.sub.2) by about 1 wt. % to 6 wt. %. The I-group oxide may include at least one of lithium oxide (Li.sub.2O), sodium oxide (Na.sub.2O), or potassium oxide (K.sub.2O).