When the process was first brought to the notice of the Lancashire bleachers, it met with an amount of opposition. Some bleaching chemists declared the process was not patentable, as fully half a century ago carbonic acid was known to decompose chloride of lime. The patentee's answer was emphatic, that carbonic acid gas had never been applied in bleaching before. After some delay one of the largest English cotton bleachers, Messrs. Ainsworth, Son & Co., Halliwell, Bolton, threw open their works for a fair test of the Thompson process on a commercial scale.
The result of trial was so satisfactory that a company was formed to work the patent. Soon after this the well-known authorities on the oxidation of cellulose, Messrs. Cross & Bevan and Mr. Mather, the principal partner in the engineering firm of Mather & Platt, of Salford, Lancashire, joined the company. For the last twelve months these gentlemen have devoted considerable attention to improving the original contrivance of Thompson, and a few weeks since they handed over to Messrs. Ainsworth the machinery and instructions for what they considered the most complete and best process of bleaching that has ever been introduced.
Recently a "demonstration" of the "Mather-Thompson" process of bleaching took place at Halliwell, and to which were invited numerous chemists and practical bleachers. Having been favored with an invitation, I propose to lay before your readers a concise report of the proceedings.
It is usual in this country to give a short preliminary boil to the cloth before it is brought in contact with the alkali, the object being to well scour the cloth from the loose impurities present in the raw fiber and also the added sizing materials. In the new process the waste or spent alkaline liquors of the succeeding process are employed, with the result that the bleaching proper is much facilitated. The economy effected by this change is considerable, but in the next operation, that of saponification, the new process differs even more widely from those generally in use. In England, "market" or "white" bleaching requires a number of operations. There is first the alkaline treatment divided into the two stages or processes of lime stewing and bowking in soda-ash, which only imperfectly breaks down the motes. There is consequently a second round given to the goods, consisting of a bowk in soda-ash, followed by the second and usually final chemicking. There is, therefore, much handling of the cloth, with the consequent increase of time and therefore expense.