▁division ▁changed ▁the ▁structure ▁of ▁the ▁plant . ▁Old ▁depart ments ▁closed . ▁ 1 9 5 8 ▁saw ▁the ▁start ▁of ▁Di olen ▁( poly eth yl ene ▁t ere ph th al ate , ▁P ET ) ▁spin ning ▁which ▁gradually ▁replaced ▁Per lon . ▁P ET ▁became ▁the ▁main ▁product ▁at ▁the ▁site . ▁Per lon ▁was ▁dis cont in ued ▁in ▁ 1 9 7 1 . ▁ ▁Ste el ▁cord ▁▁ ▁At ▁the ▁beginning ▁of ▁the ▁ 1 9 6 0 s , ▁the ▁first ▁tests ▁for ▁the ▁manufact ure ▁of ▁steel ▁cord ▁were ▁undert aken . ▁The ▁company ▁wanted ▁to ▁include ▁ty re ▁rein for cement ▁material ▁in ▁its ▁product ▁range . ▁A ▁large - scale ▁production ▁was ▁established ▁in ▁Ober bru ch ▁in ▁ 1 9 6 9 ▁which ▁Ak zo ▁ceased ▁again ▁in ▁ 1 9 9 1 ▁for ▁reason ▁of ▁international ▁competition ▁and ▁establishment ▁of ▁ty re ▁manufact ur ers ' ▁own ▁capac ities . ▁In ▁the ▁second ▁half ▁of ▁the ▁ 1 9 6 0 s , ▁the ▁number ▁of ▁employees ▁reached ▁a ▁peak ▁of ▁ 7 , 0 8 8 . ▁Gl anz stoff ▁remained ▁a ▁world ▁leader ▁in ▁the ▁production ▁of ▁man ▁made ▁fib ers ▁and ▁their ▁basic ▁products ▁up ▁to ▁the ▁ 1 9 7 0 s . ▁ ▁P ET ▁▁ ▁In vest ment ▁at ▁the ▁beginning ▁of ▁the ▁ 1 9 7 0 s ▁focused ▁on ▁modern ization ▁and ▁stream lin ing . ▁This ▁was ▁the ▁only ▁way