Poly:thiophene and soluble poly:thiophene salts - useful for prodn. of thin, transparent, infrared-absorbing layers in laminated glass sheets, esp. for car windows etc.

摘要

The use of transparent thin layers of polythiophens or soluble polythiophen salts with repeating units of formula (III) for IR absorption in laminated glass sheets is claimed. R1, R2 = H or 1-4C alkyl, or R1 + R2 = opt. substd. 1-4C alkylene. Pref., R1, R2 = H or Me, or R1 + R2 = opt. alkyl-substd. methylene, opt. (1-12C alkyl)- or phenyl-substd. 1,2-ethylene gp. or 1,2-cyclohexylene. The prepn. of these cpds. and of the IR-absorbent coatings is described in DE-OS 3813589 and EP-A 440957. USE/ADVANTAGE - As heat protection layers in laminated glass, esp. in car windows to prevent the inside of the car from overheating in the sun. The above polythiophen cpds. have excellent IR absorption properties. They do not cause problems with residual reflection or dazzle (contrast heat-reflecting layers of Ag or metal oxides, which are also expensive to produce) and they do not colour the glass green (contrast Fe(II) ion doped-glass).