US2482185A - Floor covering and composition material therefor - Google Patents

Description

Patented Sept. 20, 1949 FLOOR COVERING AND 'COIWPOSITION MATERIAL THEREFOR Fred Hubert, Jr., Essex County, and Vernon A. Kildare, Bergen Gounty, N. J., assignors :to Con oleum-Najirn Inc., a corporation of New York No'Drawing. ApplicationDecember'ZD, 1946, Serial N0. 717,594

This invention relates :to floor coverings and composition material therefor, and is concerned more particularly with floor coverings of the 'flex-..

i-ble smooth surface type comprising a strain-resistant base sheet anda suriace'layer of Wear-resistant composition material integrally united with the base sheet.

It is a purpose of this invention to provide an inexpensive floor covering made from low cost ingredients and by economical manufacturing processes which possesses good flexibility in combination with toughness and high resistance to wear and to indentation under load.

Heretofore, it has been proposed 'to manufacture flexible smooth surface floor coverings using as the binder for the surface layer of composition material pitch derived from animal or vegetable oils such as the pitch'm-aterial which is commonly referred to as stearinj pitch. However, such floor coverings, while having the advantage of low cost, also have the disadvantage of being deficient in flexibility with the result that the surface layer is excessively susceptible to cracking when the floor covering is subjected to flexure. Prior attempts to modify stearin pitch or the like by inclusion of minor amounts of natural or petroleum residue bitumens, have not been successful ,in overcoming the .diificulty abovementioned.

.The present invention is directed to a specific formulation of the composition material of the suriace layer of a floor covering of the type in question whereby" the flexibility of the composition material of the surface layer of the floor cov eri-ng is much improved without impairing its hardness; wear resistance'and indentation r istance.

.,According "to this invention, the compositionma-terial tor the surface layer of a floor covering of the type inque'stion employs a-mixture of cottonseed pitch and a small amount of gilsonite which mixture is modified by the presence of a small but critical amount of sulphur and is further modified by the incorporation of a calcareous filler such as powdered limestone. The composition material may likewise contain pigments or the like to provide suitable color, but the spe' cific ingredients above mentioned in the proportions to be more particularly defined below are essential in affording-the improvements or this invention.

In order to afford a better understanding of this invention and its employment the -manu factuiie of flexible smooth sa i-ace coverings, a typical preferred embodiment and its manufac- 4 Claims. (Cl. 11751.68)

2 ture are described .below so that a specific illustrative example may be aiforded.

According to the specific example to *be .described, the ingredients used for the preparation of the composition material of the surface layer of the :floor covering are as follows, the percentages given below and elsewhere herein being percentages by weight.

Per cent Cottonseed pitch (softening point -110 F.) .9 Cotton seed pitch (softening point .135-

In preparing the composition material for the surface layer, the cottonseed pitch, gilsonite, sulphur, and manganese =linores'inate are heated to a temperature of the order of 300 F. to 325 F. in a suitable mixer such as a Pfleiderer mixer or a steam jacketed pug mill. stone and red oxide pigment are then incorporated and the composition is cooked for approximately three hours at the temperature mentioned, the mixer being kept in operation so as to accomplish a thorough mixing of the ingredients. During this period, the composition material becomes converted into a plastic mass. It

is necessary that the composition material shallbe plastic and readily workable in the mix-er at temperatures around 300 F. and during the coat ing operation whereby it is spread as a surface layer on thebas'e sheet of the flooring. It is also necessary that the composition material exhibit little or no flow at temperatures of the order of 1-55 to 200 'F'. at which the flooring is cured or seasoned.

After the mixing has been completed, the plas-- material :can be spread on the base sheet as a coating layer in any suitable manner as by -em--- ploymcnt of :a heated doctor blade. The coating layer preferably is applied so that it thickness is of the range 0.02 inch to 0.04 inch.

After the coating layer of composition mate rial has been applied to the base sheet, the floor covering so produced is then stoved at a term,

The powdered lime stone for each 28 parts by weight of the cottonseed pitch. Preferably the powdered limestone is present in amounts such that there are present from about 30 to about 40 parts by weight for 28 parts byweight of cottonseed pitch, the optimum proportion being 35 parts by weight. Since powdered limestone is the preferred calcareous --filler, the claims call for powdered limestone in composition material is highly resistant to wear and'is hard and resistant toindentation. At the same time, the coating layer of composition material is flexible. A flooring which is of such flexibility that a 2 x 8 inch sampleat "77 F. can be bent at approximately the' center with; the felt backing on the inside through 180 of arc the relative proportions stated with the intent that if some other calcareous filler is substituted for powdered limestone such substitution would be the equivalent'of the powdered limestone if the alkalinity of the calcareous filler used corresponds to the alkalinity of the stated proportions of powdered limestone. Thus, for example, if hydrated lime, which is considerably more alkaline than powdered limestone, were to'be used 7 to replace a larger proportion by weight of the about a 4-inch diameter mandrel in about 5- sec 7 onds time and at approximately a uniform speed without development of surface cracks, possesses flexibility which is adequate for practical purposes in that the covering is not susceptible to cracking of the surface layer when'made up in rolls for shipment or during installation. The improved floor covering above described has substantially greater flexibility than that required to meet the test above described. Thus the floor covering which has been described hereinabove as affording a typical exampleof the practice of this invention has flexibility such that it can be bent about a mandrel 1 inch in diameter without development of cracks under the test conditions mentioned above. vBy contrast, a floor covering whichis otherwise similar but which lacks the sulphur component of the composition material embodying this invention and which has been seasoned until the indentation resistance'is the same, cannot be bent about a mandrel less'than 6 inches in diameter without development of cracks'and is considered commercially unsatisfactory because of its lack of flexibility due to the likelihood of development of highly objectionable surface cracks upon onlymoderate The improvements afforded according to thisinvention result from the combined effects of-the sulphur and powdered calcareous filler upon the phur' present should be not less than 0.5 part;-

or greater than 3 parts by weight. 'If less than 0.5 part of sulphur is employed, the benefits re-' sulting from its presence are not afforded to substantial degree. On the other hand, if more than 3 parts of sulphur are employed, the finished coating layer, has undesirable permanent tacki-' ness at ordinary temperatures, and the composi-, tion as a whole becomes too stiff for commercially satisfactory mixing and spreading as a coating layer. unattractive color. It is ordinarily preferred that the sulphur be present in proportion such that for 28 parts by weight of cottonseed pitch there is present approximately'l' part by weight of sulphur.

The powdered calcareous flller that is used is preferably powdered limestone which should be present in substantial amount, namely, from parts to 50 parts by weight of the powdered lime"- Moreover, the composition also developspowderedlimestone, such substitution could be made provided the alkalinity of the resulting mixture is within the range of alkalinity .afiorded bythe proportion range of'powdered limestone stated in the claims.

Gilsonite has a softening point of about 270 to 275- F. The amountof gilsonite that is employed must be confined within narrow limits. Preferably the gilsonite should be approximately 5 parts byweight for 28 parts by weight of cottonseed pitch,'the range of the gilsonite being of invention, the drier component is the drier which is commonly-referred to as manganese linoresinate and which is a compound of the drying metal manganese with selected vegetable acids and corresponds chemically to manganese tallate (8% manganese). In additionto manganese linoresinate,- other conventional driers may be employed such as manganese resinate, manganese linoleate, and manganese naphthenate. The amount of drier that is employed should be in such proportion that for 28"parts by weight of:

cottonseed pitch there will be present approximately 1 part by' weight of drier, namely, aboutv 05 part to about 2 parts bywei'ght of the drier.

. The cottonseed pitch which isthe principal component of the binder for the composition material of the coating layer for the floor covering' of this invention is the residue obtained from.

point just referred to,-as well as elsewhere herein," 1 is that determined by the standard Ring and Ball softening point test; Preferably, the softening point of the cottonseed pitch'is approximately 125 F. A single cottonseed pitch 'may be employed or a mixture of 'two or more cottonseed pitches which in combination afford a cottonseed p'itchmixture, the softening point of which is of the range above mentioned. It is somewhat preferable toemploy a mixture consisting of one part by weight of cottonseed pitchhaving a softening point of about F. to F. and two parts by weight of cottonseed pitch having a softening point of about F. to F.

In addition to the'foregoing essential ingredi ents of the. composition materialof the surface layer of the new floor coveringof this invention,-

the composition material may, and ordinarily does, contain a pigment so as to impart desired color. The pigment usually employed is red iron oxide pigment, although other conventional pi'g-' ments may be employed-such as black iron oxide;-

maroon oxide, green chromium oxide, and In: addition, other flnely divided solid substan tially water insoluble filler materials may bepresent byway of diluents or extenders such as china clay, silica or slatefloun. when: it is stated that the filler is substantially water insoluble, this does not preclude. the presence-of a filler having slight. water solubility of the: order" of? hydrated lime..

- The binder component of. the composition maxterial, namely, the cottonseed pitch,.g ils0riite,..snl'- phur, and drier, preferably constitute about-% to by weight of the composition material, although the binder content. of the. composition material may, desired, bevaried between 3.0%v to 65 by weight. of the. composition. material. The balance of the, composition con--v sists: essentially of thefiller includingzthe; finely divided calcareous filler. with. regard. to any filler other than the calcareous filler which may be present, such other filler, for example, a pigment, should constitute from 0 to 65 parts by weight in proportion to 28 parts by weight of cottonseed pitch contained in the binder, subject, however, to the over-all" limits for the relative proportions of total binder and total filler that" have beenrstatedabove; Such other filler material preferably is present in such proportion as to constitute from about 25 to about 35 parts by weight in proportion to- 28 parts by weight of cottonseed" pitch contained in the hinder, the optimum being 30 parts by weight:

When the composition material of the surface layer of the floor covering of this invention is produced within the limits of proportion and formulation stated hereinabove, the heating of the composition during mixing and during subsequent seasoning induces an interaction of the ingredients which first increases the plastic consistency of the composition and later results in the development of the tough, wear-resistant and flexible properties in the surface coating as it occurs in the finished product. In other words, in the finished product the composition material of the coating layer is the product of hardening induced by heat of the composition material that has been formulated as hereinabove described. Due to the presence of the critical proportion of sulphur, the hardening action that takes place is substantially uniform throughout the mass and improved flexibility is afforded. At the same time, the calcareous flller which is also present likewise promotes 'the development of the hardness of the composition material and serves to counteract the tendency of the sulphur to cause undesirable permanent tackiness of thecoating layer and enables the hardness and resistance to indentation under load to be controlled without sacrifice of the flexibility afforded bythe presence of the sulphur. Such action of the calcareous flller is believed to be due to its reactivity with certain acidic components of the binder material. In other words, there is an interaction of the binder ingredients with the sulphur and with the calcareous filler, which interaction results in hardening induced by heat so as to develop the hardness and indentation resistance which are required for the composition material of the surface layer of the floor covering. Notwithstanding the development of such hardness and indentation resistance the surface layer of composition material possesses greatly improved flexibility as compared with prior floor coverings of the type in question which have exhibited excessive tendency to crack upon flexure when havingsumcicnt: hardnessv and indentation resistance: to be useful as a floor covering; Moreover; the combination of the binder ingredients with the filler ingredients is; such: that the composition material can be readily and thoroughly mixed and readily spread on a base sheet as, a surface layer that. is excellently adapted tov have its ulti.- mate toughness and hardness. developed. by sons soning for only a relatively short time,

It-may'bementioned that in the absence ofthe sulphur and calcareous. filler components, acorn- POSition. material. otherwise similar to thatahove described is capable. of gradual hardening when disposed as a coating layer for. a floor covering by, seasoning at elevated temperatures, but.- in. such. case seasoning, for from 4 to 8 days at from 155 to 2.00. is required. as: compared with sea soning for only 2 to 4. days, in the case. of. the compositionmaterial for the surface layer ot'the improved floor covering ofthisinventionl While this invention is ordinarily practiced by application of the composition material of the; coating layer to a. base. sheet. consisting: of asphalt saturated felt, it. is. apparent that any other suitable. strainrresisting base sheet may be em?- ployed such as. burlap or other fabric or other:

sheet or sheet-like material; Thev floor covering of thisv invention can beproducedi in the. form of a sheet ofindefinite length and of, any, desiredwidth or can. be produced in the form of. tile-like: bodies. In the. description. of; this invention and in the claims, the reference to the product as being a floor covering of the smooth surface type is intended to be indicative of the fact that the composition material of the surface layer has a smooth surface as distinguished from a pile fabric or the like, but is not intended to exclude the production of the surface layer so as to be embossed or so as to have differences in thickness or surface irregularities.

We claim:

1. A flexible smooth-surface floor covering comprising a flexible strain-resistant sheet-like base and a surface layer of composition material integrally united with said sheet-like base, said composition material containing from about 30% to about by weight of binder and from about 35% to about by weight of finely-divided substantially water-insoluble filler material and said composition material as disposed in said surface layer being the tough, flexible and wear-resistant product of the hardening induced by heat of an intimately commingled mixture consisting essentially of the following ingredients in the stated relative proportions in parts by weight:

' Parts Colt tonseed pitch (softening point -150 1 28 Gilsonite 4-6 Sulphur 0.5-3 Drier for said pitch 0.5-2 Powdered limestone 20-50 Filler other than said powdered limestone 0-65 2. A flexible smooth-surface floor covering comprising a flexible strain-resistant sheet-like base and a surface layer of composition material integrally united with said sheet-like base, said composition material as disposed in said surface layer of said floor covering being the tough, flexible and wear-resistant product of the hardening induced by heat of an intimately commingled mixture consisting essentially of the following in- 7 7 gredients -in approximately the stated relative proportions in parts by weight:

7 Parts Cottonseed pitch (softening point 95-150" F.) o 28 Gilsonite Sulphur r 1 Drier for said pitch 1 Powdered limestone 30-40 Filler other than said powdered limestone 25-35 3. A flexible smooth-surface floor covering comprising a base sheet of asphalt saturated felt and a surface layer of composition material integrally united with said'base sheet, said composition material as disposed in said surface layer being the tough, flexible and wear-resistant prod not of the hardening induced'by heat of an intimately commingled mixture consisting essentially'of the'following ingredients in approximately the proportions stated:

' Per cent Cottonseed pitch (softening point approximately 125 F.) 28 Gilsomte 5 Sulphur 1 Drier for said pitch 1 Powdered limestone Pigment '30 4} A composition material adapted for-applica- 30 tion as the surface layer of a flexible smooth-surface floor covering and adapted to be hardened T8 7 upon being subjected-to heatto provide. asurface layer for said .floor covering which is tough, flex ible and wear-resistant,;said composition mate.- rial'containing from about 30% to; about by weight of binder and from about 35% to about by weight of finely-dividedsubstantially water-insoluble filler material intimately com-J mingled with said binder'and said composition material consisting essentially of the following ingredients in the stated relative proportions in parts by weight: a

'- Parts Cottonseed pitch (softening point -150 i F.) Gilsonite 4-6 Sulphur 0.5-3 Drier for said pitch 0.5- 2 Powdered limestone 20'50 Name 7 Date .775,635 g V Rugen Nov. 22, 1904 2,054,815 Herbst- Sept. 22, 1936 2,073,727 Jackson Apr. 27, 1937