US2270047A - Composition of asphalt saturants - Google Patents

Description

Patented 13, .1942

UNITED STATES. PATENT oFFicE '3 z,z1o,o4r- COMPOSITION OF SATUBANTS Henry S. Goodwin, East Bound Brook, and Herman I). Winters, Jr., Roselle Park,

ors to Standard 011 Development Company, a corporation of Delaware No Drawing. Application December 30, 1939, Serial No. 311,932

down.

particularly asphalt saturants that are used to waterproof asbestos-cement or similar types of building boards.

Building boards composed of asbestos fiber and Portland cement when combined under pressure into a homogeneous dense mass have high strength and great durability. Building boards being exposed to damp or wet weather for any substantial periods of time, there is a tendency of the boards to absorb sufflcient moisture to 1 cause the board .to'swell or creep. Therefore,

substantial openings are required at the joints new edges of the board are exposed when cutting. or breaking the board into smaller-pieces.

According to the present invention, it has been found that improved saturation of the boards with bitumen may be achieved at room temperatures and normal pressures by the application of asphalt in cutback form. The percentage of asphalt in the cutback determines the penetration of the saturant in the building boards .com-

of this type may be made in different forms for posed of asbestos fiber and Portland cement, that various purposes, that is, they may be made in is, when a saturant containing inthe neighborflat sheets and used as side walls, both indoor hood of 35 to 40% of asphalt dissolved in a soland outdoor. They may be corrugated and used vent naphtha having a gravity varying from 28 as roofing and sidings. There is one disadvanto 48 A. P. I., a kauri butanol solvent power tage in using boards of this type, that is, upon varying from 53 to 82 and boiling points between 168 F. and 450 F. is used according to this invention, an optimum penetration is obtained. The following table is used to illustrate the depth to which the saturant penetrates in asbestoscement boards:

Effect of composition of saturant on its penetrating ability toward asbestos-cement boards Physical inspection of Penetration of board Composition of saturant mt mm depth Asphalt Solvent used saybflt Per cent used Per cent (boiling Gravity Flash g gf g After After After asphalt (melting solvent range A. P. I. at 140 OF 2 hrs. 4 hrs; 6 hrs.

pt.). 237432 F. m8

F. F. 140 80 Naphtha 26. 0 90 82 2% 2% 40 140 0.- 17. 4 90 86 3 4 4 60 140 40 o.-..... 9. 3 90 129 1 2 2% 20 135 so 30.1 150 so 2% 2% 3 35 185 n 22. 9 150 102 3 3 4 65 185 35 r 8. 5 150+ 869 M M M 20 185 .0. 26. 1 83 3 3 3 35 185 65 19. 4 90 87 3 3% 4 40 185 60 16.9 90 92 2 4 4 60 185 40 9. 3 90 183 3 3 65 185 35 7. 5 203 1 1 1 is that when fastening the boards in place pro- 45 vision must be made to allow for such creeping or swelling of the board.

An object of this invention is to impregnate these boards to such a substantial depth with a waterproofing composition that substantially no 50 moisture will be absorbed.

Another object of this invention is to impreghate these boards to such a substantial depth with a waterproofing composition that substantially no moisture will be absorbed even though 55 According to this table, cutbacks containing smaller or greater proportions of the asphalts of various melting points do not penetrate to the same degree, that is, the greatest penetration has been obtained when a cutback' asphalt contains approximately 35 to 40% of the desired asphalt that is used in the preparation of the cutback. It is desirable to use solvents having final boiling points not over 400 or 450 F. Othersolvents may be used, for example, hydrocarbon liquids having a boiling point below 400 F., halogenatedhyd-rocarbons havingboiling points below 400 F., carbon disulfide, carbon tetrachloride,

chlorofornumethylene chlorideand the'lower boiling mono-chlor aliphatic hydrocarbons, together with pyridine, nitro-benzol, benzol aniline and mono-chlorbenzol.

Cutback asphalts having Saybolt universal viscosities varying from 85 to 105 seconds are preferred. Solvents having boiling points below 425 F. are likewise preferred.

An improvement in the manufacture of an asbestos cement building board which comprises impregnating an asbestos cement board with a. liquid saturant having a Saybolt universal viscosity varying'from 85 to 105 seconds at 140 R, an A. P. I. gravity of 16.9 to 22.9 and consisting of 35 to 40% or an asphalt having a melting point of 140 to 185 F. and 65 to 60% of a solvent naphtha having an A.-P. Iigravity of 28 to 48 and a kauri butanol solvent power of at least 53.

HENRY S. GOODWIN. HERE LAN D. WINTERS, JR.