Abstract: A novel class of squarylium infrared absorbing dyes is disclosed which are prepared by the condensation of squaric acid with a benzoxazinone. The dyes are unique in that they possess the desirable properties of squarylium dyes in general along with a narrow band of peak absorbency greater than 1000.Because of their stability to laser beams, the dyes are particularly useful in ocular products for eye protection against lasers.

Abstract: Substituted xanthene compounds are described which are capable of functioning as absorbers in high intensity light protective compositions and in materials used to prevent the transmission of high intensity light at selected wavelengths. Also described are high intensity light protective compositions containing an effective amount of a substituted xanthene compound and a polymeric compound and a material which prevents transmission of high intensity light at wavelengths between about 482 to about 556 nanometers. The material of this invention can be used to make protective eyewear, optical filters, shields for protecting a persons body from high intensity light, or shields for protecting components of an optical instrument from high intensity light.

Abstract: A portable bleacher including a mobile frame supporting a pair of hinged elongated stringer members, each stringer member carrying a plurality of seats. When the stringer members are pivotally swung to their operative position in which the stringer members are aligned and declining transversely of the mobile frame, the seats are also spaced along the stringer members in a declining attitude. When the stringer members are swung to their inoperative positions, the hinged joint between the stringer members is elevated so that the stringer members have an inverted V-shaped configuration supported on the mobile frame and contained between the side edges of the frame for over-the-road movement. The bleacher may also be provided with extensible and collapsible side rails which move with the stringer members.