The disclosure is of a lead-free glass composition including SiO.sub.2, B.sub.2 O.sub.3, ZnO, Al.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, CaO, and Li.sub.2 O. The glass is used as a cement frit and as an insulating layer in gas-filled display panels including an electrode which is insulated from the gas therein.

The present invention concerns a glass-like carbon material which may be bonded to other materials, the carbon material having a high thermal expansion coefficient and being highly applicable for use as a slider part for a recording medium.

A method of manufacturing a polygonal glass fiber is disclosed. According to an embodiment of the present invention, a glass in a melted state is poured into a dividable polygonal slit having a cross section 5 to 20 times larger than a finally required cross section of a glass fiber to be made, and the glass poured into the slit is drawn so as to make a polygonal glass fiber. According to another embodiment of the present invention, a glass in a melted state is passed through a twin roller having a required cross section so as to make a polygonal glass fiber.

Disclosed are an adhesive for oxide ceramics, which comprises as its effective ingredient a crystallized glass mainly comprising SiO.sub.2, Al.sub.2 O.sub.3, Li.sub.2 O, MgO and/or ZnO, and TiO.sub.2 and/or ZrO.sub.2, and also a method of bonding oxide ceramics together, which comprises heating oxide ceramics to be bonded together at 1200.degree. to 1600.degree. C. with the adhesive placed between the ceramics.

A low magnetic isolation closure glass for use in multitrack magnetic tape heads has been prepared by combining a specific lead borosilicate glass with a specific borosilicate glass in a 60/40 weight percent ratio. The glass formed from the combination exhibits compatibility with ferrite and has reduced wear. Controlling the anneal temperature regulates the residual stress of the closure glass produced, and thus, provides some control over the wear characteristics of the glass.