Date of Award


Degree Name

Bachelor of Science


Paper Science and Engineering


The object of this thesis was to determine if the addition of Anthraquinone to sulphonated CTMP process would increase the optical properties without decreasing the strength properties. Along with the AQ addition, the percent refining done on the fibers was increased to see what effects it would produce on the optical properties.

The pulp used was southern pine and was obtained from American Fibrit Company, Battle Creek, Michigan.

The distinction that sulphonated thermomechanical pulps produce a outstanding material for inexpensive paper such as newsprint has been known for a long time. With the introduction of high brightness newspaper, like USA Today, has come the need for brightness levels of around 60 . To reach these higher levels the pulp companies have increased the bleaching process, which produced a lower yield. To correct this problem bleached kraft was added, typically levels around 20-25% have been added. With these high levels of kraft needed an alternative pulp which costs less is needed.

The results showed that with the addition of 1% Na2SO3 and 0.2% AQ the optimum optical properties could be attained. This combination produced a brightness increase of 1.5 points and only a slight decrease in opacity.