US1771643A - Fibrating process - Google Patents

Description

Patented July 29, 1930.

"UNITED STATES PATENT OFFICE ALAN R. LUKENS, 0F WYOMING, OHIO, ASSIGNOR TO THE RICHARDSON COMPANY, OF LOGKLAND, OHIO, A CORPORATION OF OHIO vIEIBIIEtA'JJIIlT G PROCESS No Drawing.

R My invention relates to modes of incorporating fibers into bitumen or other binders by the Woodleyprocess, U. S. Patent No; 1,156,122, of tearing a fibrous mass into its individual fibers by the extension of a gummy mass of binder in the presence of the fibrous mass. By this means the gummy mass becomes fibrated completely and the fibers, each individually coated with the gummy material, are interlaced in a flotant condition in the solid solution of the binder.

The use of water in a fibrating process in which the Woodley fibration is obtained, was pointed out by Woodley and is of Very high value, in facilitating the disintegration of a fibrous aggregate and the coating of the fibers, but it is not always practicable to get the proper aqueous film about the fibers when they exist in aggregated masses. Furthermore the use of water in appreciable quantities in a material to be added to bitumen will, as taught by l/Voodley, cool the same to a gummy honsistency, and While this is desirable, still if the asphalt is somewhat hard at temperatures around boiling point of water, the amount. ofwater as such will be limited and will cut down the time of the operation. Thus when wet fibers are added to asphalt, unless the asphalt is greatly in excess, the temperature ofthe whole mass will fall to and remain at close to 212 degrees F., irrespective of the amount of heat applied, until the water has been entirely evaporated. In ordinary practice I have found that the temperature of a hot binder into which fibers are introduced in the proportion suitable for the manufac ture of molded articles, will not rise appreciably above 215 to 220 degrees Fahrenheit.

Again the necessary heat for keeping the binder from becoming solid as distinguished from plastic,,must be closely controlled in order that the fibers are not scorched and in order that the process does not require a working for so long a period to drive out the moisture, that the fibers are torn into pieces that are too short to effectively tie the" mass together.

It is an object of my invention to permit the Application filed August 28, 1925. Serial No. 53,209.

disintegration of a substantially wet fibrous material in a gummy binder at higher temperatures than have hitherto been possible. It is an object of my invention to ensure the proper watery condition of the fibers. v

It is further an object of my invention to expedite the mixing time to save wear and tear on the mixers and to lower the power consumption incident to the fibration process.

Simply told, I take the fibers, or equivalent material, and first soak them in water, and place them in a steam jacketed mixer of heavy duty type, containing asphalt and then treat the products before mixing with steam for a period which thoroughly drives the moisture into the fibers or the mass and incidentally heats the fibers and softens the body of the binder so that so prolonged a mixing is not required, and a fibrated mass of longer fibers is produced in a shorter time with more complete a fiotant condition of all fibers, and a more thorough coating, whereby the physical properties of the resultant moldable compound are'co-ntrolled to the end of .producing a final molded product with the required strength, acid resistance, etc.

Referring more particularly to a typical example of my process, I may take cotton linters, either with or without some oily card, and pass a web formed of these fibers through a tank of water in order to get the mass to take up water and become well soaked.

Into a steam heated mixer, I place a measured quantity of asphalt which is an excellent binder to use with my process, and then I place sufiicient fibers into the mass to give the desired effect. For acid resistant purposes not more than by weight of the mass should be fibrous.

The lid of the mixer is then closed down tight, and a jet of steam is played upon the materials therein. This steam treatment will 4 be kept up for some minutes, until the fibers are hot and the water is thoroughly driven into'a phase of surrounding each fiber. As stated the asphalt will also be heated by the mixer itself and by the steam played upon it.

The blades of the mixer are then stirred and heat is applied thereto, say at around 300 degrees Fahrenheit, which is safe for the fibers. During the mixing, the steamtreatment ma be kept up as indicated or may be dispensed with after the proper softening and saturating action is completed. The

5 melting point and other characteristics of the is made up in exactly the same way as is saturatable character.

V masses.

mix even though less than half the mixing time formerly necessary, is used. Furtherhere indicated for fibers. The action of mineral matter I find to be closely analogous to the action of fibers, particularly inasmuch as many mineral matters, as for example the diatomaceous earths,.are of'a porous and This mineral matter mix is finally placed into the finished mass and a short mixing given to intermingle the The makingof two mixes, one fibrous and one containlng mineral matter, is the sub ect of my co-pending. application Serial No.-

610,704,' filed {1th day of January, 1923. By this means I save the fibers from being chopped up by the abrasive character of the mineral. In practice I have found that under the old method of making the fibrous mix, complete saturation was not obtained before the time of incorporation with the mineral matter mix even though the operation had been carried on for a considerable length of time. Thus it was frequently found necessary to continue the intermingling or mixing of the two separate mixes in order to obtain complete saturation with the result that the fibers were, to a certain extent, disintegrated by the abrasion. With my present process, however, I find that complete saturation is obtained in the fibrating more I find that I can make up .a fibrous mix and one containing mineral matter and store them for considerable periods of time, subsequently giving these separate mixes a short preliminary treatment by my present process, then combining them together into a completed andpracticable plastic composition for molding purposes.

I have given a single example which will be suflicient for various kinds of binder, whether the same are to be subsequently vulcanized or not or whether instead of water as a film for surrounding the fibers some other phase agent that is replaceable-by the binder is used to wet the fibers.

Naturally my process has its specific applicatlon to water processes of fibration particularly. I have found in such a process that the power consumption by my new method is less than one-half of that formerly considered necessary, that the number of mixers necessary for the operation of a single unit is considerably reduced, that the wear and tear on the mixers is cut down materially. Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

1. A process of incorporating fibers into a mass by extension ofa gummy binder in the presence of the fibers, which consists in soaking the fibers in water, placing the binder and the soaked fiber into the presence of steam in a closed'vessel to fully surface all fibers with the water, and heating the assembled masses, and finally extending the binder in the presence of the fibers while retained in a gummy condition by the application of eat.

2. A process of incorporating fibers into a mass of asphaltic nature, which consists in wetting the fibers, placing them into a mixer together with the asphaltic body, applying heat to the mixer, and blowing steam into the mixer when closed to complete the wetting of the fibers, and heating the assembled materials, and finally mixing the materials together in the presence of heat sufficient to maintain the asphaltic body in a gummy condition, short of liquefaction.

A fibration process which consists in placing a binder which becomes gummy with application of heat but is solid at normal temperatures, and a wetted fibrous mass, into a mixing device, when closed blowing steam into the device to'complete the wetting of all fibers, maintaining the gummy consist ency of the binder by heating the assembled.

materials, and finally, mixing the materials together until the steam of evaporation ceases to come off in appreciable quantities.

4. A fibration process which consists in mixing together in the presence of heat, a

gummy binder, and a fibrous mass which has been wetted with water, and thereafter treated with steam in a closed vessel, for the purpose described. 4

5. A fibration process which consists in mixing together in the presence of heat, a gummy binder and a fibrous mass which has been wetted with a desired surface filming agent, and thereafter treated with steam .in a closed vessel, for the purpose described. ALAN R. LUKENS.