US1130717A - Process of treating masses of concrete. - Google Patents

Description

CARLETON ELLIS, F MONTCLAIR, NEW JERSEY, ASSIGNOR .TO NEW JERSEY TESTIQ'G LABORATORIES, A CORPORATION OF NEW JERSEY.

PROCESS OF TREATING MASSES OF CONCRETE.

No Drawing.

To all whom it may concern:

Bevit known'that l. CARLn'roN Ennis, a citizen of the United States, and a resident of Montclair, in the county of Essex and- State of New Jersey, have invented certain new and useful Processes of Treating Masses of Concrete, of which the following is a specification.

This invention relates tov a method of treating cement or concrete surfaces and relates in particular to the treatment of conforts have been made to overcome the diffi- 'culty, but without satisfactory results.

The usual method is to flood the surface with a hard varnish so theta film of the dried varnish surfaces the concrete. Owing to the lack of resiliency of concrete such a surface even if secured by the use of several coats of very hard drying varnish, is easily abraded. WVater glass, fluosilicates, and various drying oils have been used without satisfactory elimination of dusting.

Floor concrete usually is given a troweled surface or granolithic effect and the finishing coat is generally of high cement and low sand content. I Also by troweling the finer particles of cement and sand work toward the surface while the coarser particles sink beneath. '7 This results in a glazed or smooth surface to which varnish coatings do not cling readily and the density of the extreme surface layerprevents penetration of the varnish to any great extent. Such coatings readily peel and repainting or recoating is soon required.

In the present invention the surface of the concrete mass is left open to secure proper penetration of the coating or as this IS often impracticable the troweled or granolithic finish is etched with acid and the like after setting or washed with water'j ust after the initial set and before the final set, orin other waysroughened so that the surface of nearly neat cement is evenly etched or "opened so as to permit of the subsequent treatment. After drying such an opened Specification of Letters Patent.

Patented Mar. 9, 1915..

Application filed September 25, 1911. Serial No. 651,185.

surface the coatin material is lied. The first coat shouldfim rather thinin ody, preferably, so as to secure a substantial anchoring foothold. Subsequently one or more coats of the material are applied to build up a stratum in and around the particles of concrete or cement which has a mean height substantially that of the average height of the projecting ranules or rugosities of the roughened sur ace. Thus several important advantages are secured by this procedure. First, the coating is securely anchored to the surface; second, the peaks In carrying out my invention I prefer-- ably as stated roughen the surface of the concrete mass with acid, using for example a five or ten per cent. solution of hydrochloric acid, or a fifteen per cent. solution of sodium bisulfate, or similar acid wash. A mixture of three parts of sodium bisulfate"to one part of magnesium chlorid is useful, as roughening is secured without material weakening of the bonding of the set cement. This mixture is used in about the proportion of one and one half ounds to the gallon of water. These rougffening washes are al lowed to remain on the surface until the desired degree of rugosity'is secured, when the surface is washed and dried. The surface is now ready to be treated with the coating or impregnating waterproofing or hardening material. The selection of the material for this purpose depends to some extent on the service to which it is to be put. For oflice buildings and the like of a generally dry character a short oil varnish may be used.' This may be repared from copal gum, such as'Ma-nila, auri, Zanzibar, Pon-' tianak, Borneo and the like, with wood oil or other drying oil capable of producing a tough film with varnish gum after suitable heat treatment. or Pontianak rubber resin maybe used with a drying oil, with or withused, although this material has certain disterials.

out additions of the resins mentioned. As Pontianak rubber resin is substantially unsaponifiable it is well adapted for such uses, as it is not affected by cement alkali. However under the present invention there is no longer need of using expensive hard gums and oils for surface treatment, as the rugosities of the surface protect the waterproofing film from material abrasion for a long time. Muchcheaper materials, such as solutions of Pontianak rubber resin or Manila resin and the like in a hydrocarbon solvent may be used; and although more brittle than the oil varnishes they are sufficiently protected by the rugosities so that they are preserved from abrasion for an indefinite time. A small amount of ceresin or paraffin wax or other waxy body gives a slight tempering effect without materially affecting the cost. Larger amounts soften the resins considerably and in such cases the rugosities are made quite prominent, so that the softer material is better protected. Tetrachlornaphthalene and also pentachlornaphthalene are extremely good waterproofing agents and when mixed with resins in about equal proportions and suitably thinned form a dust preventing and waterproofing material which is excellent for mill floors and fac-v tories where dampness prevails, or where acids or other chemical reagents are employed.

As stated, the first coat should preferably be of'thin consistency so as to secure effective penetration and form an anchoring layer. Subsequent coats are better applied of heavier body so as to quickly fill the depressions to practically the level of the surface peaks, or thereabout. Various pigments may be used in the floor coatings as well as the usual filling. andextending ma- The addition 7 of rather coarsely ground silex,-pumice and the like secures greater frictional foothold. Pulverized alundum is especially satisfactory in this respect, as a small quantity serves for a .large surface and the attritional or fric tional reinforcement to the peaks of natural origin obtained in this way is extremely useful in'floors subjected to extreme service conditions. Carborundum also may be advanta es which do not appear with alundum an similar artificial peak-formers.

Instead of using surface filling materials of a varnish character, other compositions may be used, as for example, a mixture of zinc oxid and zinc chlorid, or of magnesium oxid and chlorid, preferably admixed with artificial peak-forming material of an extremely hard nature. For example the surface may be treated with zinc oxid and alundum in water which has been bodied with a little alkali-casein and after drying a concentrated solution of zinc chlorid is applied.

A zinc oxychlorid cement forms and as soon as this has set the surface may be washed and dried. If desired a coating of varnish may be applied over this.

The condensation products of carbolic acid other cresolor other phenol may some time be employed to good advanta e, especially when the cement is nammfi rough and open and has not been etched -with acid. Condensation products made with either and acid or alkaline condensin or catalytic agent may be employed and i desired the surface, after coating or impregnation, may be heated to superficially form a hard, infusible, condensation product of great durability.

If the cement flooring or its upper layers carry a Waterproofing agent of the integral stantially to a level with the peaks thereof,

with a dust-preventing and waterproofing material; whereby the wear is taken substantially by said peaks.

2. The process'of treating-masses of concrete which comprises roughening a surface thereof in impregnating such surface with a water-resistant binding material and infilling the depressions of said surface substantially-to a level with the peaks thereof, with a dust-preventing and waterproo terial of a finish coating character; whereby the wear is taken substantially by said peaks.

3. The process of treating masses of concrete which comprises roughening a surface thereof in impregnating such surface with a water-resistant material as an anchdring coat or layer and in filling the depressions of said surface substantially to a level with peaks thereof, with a material of a dustpreventing and waterproofing Y character, carrying an extremely hard granular abrasive serving as frictional material; whereby the wear is taken substantially by said peaks.

4. The process of treating masses of concrete and similarmaterial used for fiooring purposes which comprises roughening the surface thereof by removal of very fine cement material and consequent exposure of coarser aggregate and sand grains, in su rficially impregnating .the roughened sur ace thereof. with a water-resistant material as an anchoring layer, and in fillin the depressions of said surface substantlally to a level with the rugosities thereof, but no higher, with a dust preventing and waterproofing binding material of an organic character; whereby the wear is taken substantially by said peaks. 7

5. The process of treating masses of concrete which comprises roughening andsuperficially impregnating a surface thereof with a water-resistant binding material and in filling the depressions of said surface substantially to a level with the peaks thereof, wi a dust preventing and waterproofing material of a finish coating character;

whereby the wear is taken substantially by said peaks.

Essex and State of New Jersey, this 22nd day of September, A. D. 1911.

CARLETON ELLIS. Witnesses: v

.RoBT. M. HENING, EmzABErir M. MARTIN.