US940317A - Sizing composition. - Google Patents

Description

ILLIAM HOSKINS, OF LA GRANGE, ILLINOIS.

SIZING COMPOSITION.

No Drawing.

Specification of Letters Patent. Application filed Iareh 19, 1909. Serial No. 484,539.

Patented Nov. 16, 1909.

To all whom it may concern:

Be it known that I, WILLIAM Hosxms, a citizen of the United States, residing at La Grange, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Sizing Compositions, of which the following is a specification. 1

My object is to provide, as a new article of manufacture, paper-sizing compounded in such a way'as t-o'render its use by paper manufacturers particularly convenient and economical andzenable them, furthermore, to effect the results desired in the ultimate paper product with greater uniformity and less trouble than hitherto.

In the rosin-soap, called rosin-size,'is added to the pulp during the beating operationand thoroughly mixed therewith. Alum, or aluminum sulfate, is then added to react with the rosin-soap and decompose and set free rosin and form aluminum resinate. Authorities differ as to the precise reactions that take place, but the effect upon the pulp is to cause a certain amount of the rosin, or aluminum resinate, to adhere to the particles of fiber, so that when the sheet of paper is made it is less pervious to Water than would be the case without the sizing. The rosin-soap is ordinarily produced, at the paper mill, by heating the rosin in contact with a solution of soda ash, or caustic soda, by means of steam. To produce a good quality of sizing requires time, skill and care, and to effect the best results a knowledge of the purity of the constituents is necessary for the purpose of arriving at the correct proportions to be used and to avoid waste. Different lots of size will vary materially in the proportion of water present, and this leads to uncertaintyas to the quantity of size to be added to the pulp, and also to the alum required, and this uncertainty tends toward inferiority and lack of uniformity in the final prodnet and also to a waste of material.- To

avoid the above difiiculties I provide a uniform sizing mixture so compounded as to produce the desired results in an unvarying manner.

In carrying out my invention I proceed as follows: T 0, say, 100 pounds of a certain lot of rosin I add approximately 11% pounds of caustic soda, the precise amount necessary for any given lot of rosin being accuratel determined by chemical test. 'I also add su ficient water, say, 25 per cent. of the weight process of manufacturing paper,

of. the alkali, to cause'ready saponification. These ingredients are thoroughly mixed together and heated, preferablv in a steamjacketed chamber, until saponification is complete. .'I he mixture is then allowed to cool, becoming a brittle mass of rosin-soap, easily pulverized, and after its pulverization I mix with it, say, pounds of an inert pulverulent material, such as china clay, or talc, to prevent the particles of the rosin-soap from adhering ,toeach other and forming lumps, as would occur if moisture wereabsorbed thereby, or if its temperature were raised. To the dry pulverulent mixture thus produced, I prefer to add, say, 16.6 pounds of a dry and powdered rosin-soap-decomposing reagent, such, for example, as aluminum. sulfate, incorporating it thoroughly with the other particles. I find that it is desirable to use as such reagent dehydrated alum -(alum which has been deprived of its water of crystallization), as this dissolves in water much more slowly, even in a powdered state, than does the powdered rosin-soap, thus allowing time for the thorough mixing of the soap with the pulp before it is acted upon to any extent by the alum.

Dry rosin-soap when in lump form dis-. solvesvery slowlyand when it isemployed the practice is to liquefy it by heating in contact with water before adding it to pulp in order to mix therewith quickly and properly. If the rosin-soap is pulverized, however, and kept from agglomerating into lumps, as b having incorporated with it an inertmaterlal, such as powdered china clay, it dissolves quickly. China clay is frequently used as a constituent part of paper pulp, and the relatively small quantity of the same, or equivalent inert material, necessary for'keeping the rosin-soap in a pulverized condition, would beof no disadvantage to the paper. Pulverized rosin-soa mixed with a suitable quantity of pulverize inert material may be provided wlthout the decomposing reagent to paper manufacturers, who, after mixing 1t with pulp, could add thereto the desired quantity of alum or equivalent material. I believe, however, that,'as a rule, a more uniform and desirable product would be obtained by paper manufacturers if the compound of pulverized rosin-soap (of known chemical composition) and inert material, has mixed therewith, in the first instance, only the necessary and most desirable quantity of soap-decom- I suitable proportions,

posing reagent, also of known analysis, thereby making it necessary to follow but the single rule of mixing a given quantity of the compound with a given amount of paper stock for certain results.

The compound may be provided in bags or other suitable packages and by its use littlevskill or judgment on' the part of the operator is required for producing the desired results in paper manufacture.

What I claim as new and desire to secure by Letters Patent is-- l. A paper sizing compound, consisting of a mixture of saponified rosin, inert material and a. rosin-soaprdecomposing reagent, in

all the ingredients of the mixture being in dry, ulv'erulent condition, for the purpose set orth.

2. A paper sizing compound, consisting of a mixture of saponified rosin, inert material and a rosin-soap-decomposing reagent more slowly soluble than rosin-soap, in suitable proportions, all the ingredients of the mix ture being in dry, pulverulent condition, for the purpose set forth.

3. A paper sizing compound, consisting of a mixture of 'sa'ponified rosin, inert material, dehydrated alum or aluminum sulfate, in suitable proportions, the mixture being in dry, dition, for the purpose set orth.

WILLIAM HOSKINS,

In the presence of J. G. ANDERSON, R. A. RAYMOND.

all the ingredients of ulverulent con-