British Polythene Industries expects annual results to be at the "top end" of market expectations.
The Greenock company said it is succeeding despite flat demand from customers.
It said: "There is subdued demand from many industrial customers and, at best, overall flat volumes from the retail sector."
However a softening in raw material prices, structural changes put in during the past few years and strong trading in its European business means the polythene manufacturer is confident it will hit its targets for 2011.
The company's preliminary results will be announced on March 5, 2012.