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 glass has a low ratio of density ρ and refractive index n.sub.d. The glass has a refractive index n.sub.d in a range of 1.80 to 2.00, an internal transmission of at least 80% (450 nm, 10 mm), a dispersion v.sub.d of 19.0 to 27.0, and a ratio ρ/n.sub.d of <1.97.

Fluorescent rare earth glass frits are suitable for laser marking. A marking composition including fluorescent glass frits is disclosed that is capable of emitting fluorescence under irradiation of ultraviolet rays. A method of forming marks or indicia on a substrate using the fluorescent rare earth glass frits is also disclosed.

Fluorescent rare earth glass frits are suitable for laser marking. A marking composition including fluorescent glass frits is disclosed that is capable of emitting fluorescence under irradiation of ultraviolet rays. A method of forming marks or indicia on a substrate using the fluorescent rare earth glass frits is also disclosed.

To provide a glass composition for glass fiber that includes biosolubility and can achieve long fiber formation. The glass composition for glass fiber of the present invention includes SiO.sub.2 in the range of 35.0 to 55.0% by mass, B.sub.2O.sub.3 in the range of 10.0 to 30.0% by mass, Al.sub.2O.sub.3 in the range of 14.5 to 30.0% by mass, and CaO and MgO in the range of 8.7 to 25.0% by mass in total, with respect to the total amount, and the content S of SiO.sub.2, the content B of B.sub.2O.sub.3, the content A of Al.sub.2O.sub.3, the content C of CaO, and the content M of MgO satisfy the following formula (1):

[00001]$\begin{array}{cc}11.3\le \text{S}\times \left(\text{C}+\text{M}\right)/\left(\text{A}+\text{B}\right)\le 20.7& \text{­­­(1)}\end{array}$

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); 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.

A tubular member for an exhaust gas treatment device according to at least one embodiment of the present invention includes: a tubular main body made of a metal; and an insulating layer formed at least on an inner peripheral surface of the tubular main body. The insulating layer contains glass containing a crystalline substance, and the insulating layer has a porosity of from 1% to 12%.

A tubular member for an exhaust gas treatment device according to at least one embodiment of the present invention includes: a tubular main body made of a metal; and an insulating layer formed at least on an inner peripheral surface of the tubular main body. The insulating layer contains glass containing a crystalline substance, and the insulating layer has a porosity of from 1% to 12%.

Embodiments of the present invention pertain to glass compositions, glasses and articles. The articles include an aluminosilicate glass, which may include P.sub.2O.sub.5 and K.sub.2O.