US2159586A - Bituminized web - Google Patents

Description

May 23, 1939. H. w.- GREIDER E'r AL. 2,159,586

BITUMINIZED WEB Original Filed July 20, 1933 ATTO R N EYS Patented May 23, 1939 m'rUMINIzED WEB .Harold W. Greider,v Wyoming, and George Arthur Fasold, Cincinnati, Ohio, assignors to The Philip Carey Manufacturing Company, a

corporation vof Ohio Original application July 20, 1933, Serial No. 681,286. Divided and this application May 26, 1937, Serial No. 144,964

4 Claims.

'I'his case is a division of application Ser. No.

681,286, iled July 20, 1933, (Patent No. 2,105,531 issued Jan. 18, 1938) which is incorporated herein as a part of the disclosure of the present invention. The apparatus, method and article are all disclosed in the parent case, but the subject thereof is the'method.

This invention relates to waterproofed web material,. and particularly pertains to Woven or felted web material, such as felt, paper fabrics and the like impregnated with land/or coated with bituminous composition to be used as building material and the like for weather resisting covering such as roofing, siding and the like.

Two serious defects encountered in bituminized fabric roofing as heretofore made, have been its tendency to blister and slide, and it is the aim of this invention to provide waterproofing web material VAfor the manufacture of bituminized roofing having neither of these objections.

Bituminized building material heretofore employed for roofing and siding contained a considerable number of voidscaused by incomplete saturation with asphalt and entrapment of air during its manufacture. Accordingly when the material is exposed to the weather, moisture is absorbed either by direct application of Water or by contact with moist air. This is due chiefly to the porosity of the sheet that results from incomplete saturation and entrapment of air, but also in part to the porosity of the pulverulent or granular material which is adhered thereto and apparently affords communication with the internal minute air pockets or voids either through or along the sides of the granular particles. Tests have shown that many'roofing felts and roongs heretofore made when soaked in water for one hour at 120 F. will absorb as much as to 20% of Water or will absorb from 10% to 30%l water in twenty-four hours at 77 F. Further tests have shown that when such porous moisture-laden roofing is exposed to hot summer when exposed to summer heat. Sliding, of course,

is particularly serious on inclined roofs or Vertical walls. Frequently shingles of ordinary size exhibit 1% inch ror more slide after having been in place for some time. Sliding, of course, is ruinous both to the appearance and the weather durability of the roofing.

It is the aim of this invention to provide a roofing material which is devoided of air and effectively sealed against the penetration of air and moisture, `and has' included in its structure a layer which is of a character and is so associated with the foundation as to prevent relative movement of the components making up the roofing material. In other words, the aim of the invention is a roofing material which is substantially non-blistering and/or non-sliding. More specifically one of the features of the new y, roofing is that it is substantially completely devoided of air and contains a. 'layer of web material impregnated with a bituminous saturant and second layer of web material impregnated with bituminous materialv having a substantially higher softening point than said saturant. In a preferred embodiment of this invention the airdevoided roofing contains an inner layer of web material and two layers of web material which are on each side of said inner layer and which are impregnated with a bituminous material having a substantially higher softening point than the softening point of the saturant for the inner layer. Further features of this invention reside in the fact that the webs of the layers are felts and that the felts of these layers are interfelted. Thus, a felt is impregnated with a saturant of one softening point and also impregnated adjacent the surface or surfaces thereof with a bituminous material of substantially higher softening point, the bituminous material of higher softening point sealing the air-devoided felt and being keyed to the felt. A further feature resides bituminized web impregnated with a bituminous saturant and also impregnated within its surface layer or layers with a bituminousmaterial having a higher softening point than the saturant, of a bituminous coating which is integrally bonded with the higherl softening point bitumen and which has a higher softening point .than the saturant. Thus the product not only contains coating materialof relatively high softening point impregnated in a surface layer of the felt and keyed thereto but also a second layer of higher softening point bituminous coating material contacting with the higher softening 4point bituin the combination with ar ing because the high softening point bitumen used as the surface sealing layer is applied while the impregnated sheet is devoided of and Vunex- A posed to air;

It is a further feature of one embodiment of this invention that there is employed in combination-with a web impregnated with a saturant and sealed with a coating material having ahigher softening point than said saturant, a second coating material which has a higher softening point than the saturant and which con tains a mineral filler.

A further feature of roofing embodying this invention is that the coating material which does not impregnate the web but overlies the same can be of reduced thickness and weight. Thus, when the web is completely impregnated and all its voids filled with bituminous saturant and part of the coating bitumen is impregnated in the surface of the web, less coating has to be used overlying the web to attain a desired finished weight of the roong and this fact coupled with the keying of the coating to the web and the contacting of coating impregnated in the web with coating overlying the web, results in a finished product which is very resistant to sliding.

In the new roofing of this invention the web of felt, for example, is protected perfectly. It is completely impregnated with a bituminous saturant and it is sealed in a devoided condition so that it is substantially non-porous and so prevents moisture from entering and causing blistering and deterioration of the web. 'I'he saturant, sealing layer and coating layer become virtually a single, integral, non-porous waterproofing layer; hence the roofing embodying this invention has a greater durability and resistance to weathering. This is true Whether weathering action is applied to the roofing on the weathering surface or at cut edges. Roofing heretofore made has been particularly susceptible to penetration of moisture from cut edges with particularly rapid deterioration at such points. In the new roofing of this invention the portion exposed by cut edges is substantially free of voids and moisture is unable to penetrate and to cause deterioration.

It is a further feature of the new product of this invention that the Water absorption is very low. 'Ihus samples of roong material to be substantially non-blistering should have less than 2.0% water 'absorption ywhen soaked in water for 24 hours at 77 F. and a product having less than ,about 2.0% of water absorption under the above conditions is to be regarded as coming `within the scope of this feature of this invention. By the practice of this invention it has, infact, been found possible to produce roofing having lessv than 0.5% void, as determined by soaking the roofing in water at`r77 F. for 24 hours. Further purposes, features and advantages of this-'invention will become apparent in the following description of the illustrative embodiment of this invention in connection with the accompanying drawing, wherein:

Fig. 1 is a sectional View of a roofing materia embodying the invention; and

Fig. 2 is a sectional view of a modified 'form of roofing embodying the invention.

Referring to the drawing in which like nu` merals are used to designate like parts, a web 18 of suitable fibrous material, preferably felt, is impregnated with a saturating material 18. One method of saturating is to unroll the web i from a supply roll or rolls and pass it progressively through a saturating tank containing the saturating material heated from about 350 F. to 400 F., although the temperatures named are not regarded as critical.

'I'he saturating material I9 is preferably a relatively low softening point asphalt. The lower softening point asphalts undergo deterioratlve oxidation and hardening less rapidly' on weathering and are more flexible. Moreover, in melting them sufficiently to make them fluid enough to permit a web to be impregnated therewith, they do not have to be heated to temperatura which are so high that burning'and weakening of the web occurs during the time that is required to impregnate a dry web. Preferably, a saturant is used which has a softening point of about to F. as determined by the ball and ring soft and too flexible and that if a saturating material having too high softening point is used there is likelihood of burning the web during the saturating step and of producing a product which is too rigid and subject to excessive cracking when flexed and of reduced resistance to weathering.

During the immersion of the web in the bath of bituminous saturant, it may be advantageous- -ly passed alternately over any number of rolls disposed in the saturating tank to be submerged below the surface of the saturant, thereby causing thorough impregnation of the web with the saturant. Excess saturant is removed from the .web after it emerges from the saturant bath.

It has been found in practice that it is desirable to have sufficient excess saturant removed toleave the web in a spotted condition, namely, having certain areas appearing wet and certain areas appearing dry. `I f, too great amounts, of saturating material are left adhering to the surface of the web, this material acts as a lubricant for higher melting point coati/ng applied thereto with the result that the finished product has a tendency to slide. If the saturated felt is made too dry it is diiiicult to remove all the air from the felt prior to the coating and sealing of the felt.

The saturated web is then treated with bituminous sealing material 80 prepared with a harder consistency and of a higher fusing point than the saturant. It has a softening point preferably between about 220"v F. and about 250 F. and a penetration of about 9 to 20 at 77 F. However, satisfactory results can be obtained when the softening point ranges from about F, to about 275 F. and the penetration ranges from about 50 to 5 at 77 F. The sealing material is preferably applied at aout 425 F. although about 50 to 75 F. variaion from this range will still a'ord satisfactory r sults.

The sealing material 80 is. applied while the saturated web is substantially devoided of air, and this may advantageously be carried out by aisance `such as a pair oi' squeeze rolls, may be disposed in the tank, submerged belowthe surface of the molten' sealing materialI to expel air from the saturated web. The sealing material is applied while the saturated sheet is devoided of air and while compressed. Accordingly re-entry of air is precluded by the sealing means, and as the saturated web tends to re-expand, upon release of the compressing force, the sealing material is drawn into the voids from which the air has been expelled, thereby sealing the saturated web against the entry of air and providing in the surface thereof a layer ililing the surface interstices to a substantial depth and interlocking with the web. An excess amount of sealing ma` terial may be applied to the web in .order to provide a coating layer of the sealing material on the surface of the saturatedweb as well as lm pregnated therebeneath, or any excess may be removed leavingonly a sealing layer impregnated to a substantial depth beneath. the surface of the web.

It is preferable in the practicing of the invention that the sealing material be applied as quickly as possible after the saturating so as to avoid the absorption of air by the web which would otherwise occur due to the cooling of the web and expansion thereof after having passed the compressing means. Preferably, although it is not essential to the practice of the invention, the web is not permitted to cool substantially, e. g., more than a few degrees, in passing from the saturating bath to the coating bath. Immersion of the web in the hot sealing material partially devoids it, and while immersed in the bathof sealing Vmaterial, it is compressed preferably to a definitely greater extent than that resulting from the use of any doctor means for removing the excess saturant at the conclusion-of the saturating bath. After compression is released, the web, covered with the sealing material, expands and draws in said sealing material to replace the air that has been expelled. Accordingly, the web is thus not only filled with saturant but also is sealed with the sealing material which permeates the web surface andy keeps the web in a permanently devoided condition. It is to be noted that the web is maintained devoided during application of the sealing material. After the web has been iilled with the saturantrand sealed with the sealing material as above described, it may be used without further treatment, other than be-` ing subdivided into smaller units, cut from the sheet. It vis adapted for various uses such as flooring, built-up roong, pipe line covering and the like. a

For roofing purposes, however, it is preferable to apply a coating layer 82 of the same character and composition as the sealing material to give increased thickness, resistance to weathering and to afford a layer of suiiicient thickness to hold adherently a finely divided, e. g., granular solid material 83, such as vslate granules of suitable color. It is preferable to apply this coating before e cooling the'sealed web. Additional coating with pulverulent material 8| such as finemica flakes. In this structure, there is an inner portion of felt impregnated with an inner layer of saturant and two overlying portions of the felt impregnated with outer layers of sealing material having a higher softening point than said saturant. The bituminous material in layers 88 and 82 are substantially identical and become merged with one another so that a coating is afforded comprising bituminous material which impregnates the felt and is keyed thereto and a surface layer 82 which overlies the felt and which has susbstantial thickness and weather-resistance.

. A modified embodiment of the invention is shown in Fig. 2. The structure in Fig. 2 is identical with that of Fig. 1 except that in place of the layer 82 shown in Fig. 1 a layer 84 is employed of coating material which is substantially dierent from the coating material contained in layer 80. Thus, for example, a coating material having a different softening point fromfthe melting point of the'coating material contained in layer 80 may be employed. Moreover, the coating material in layer 84 may comprise a bituminous layer having dispersed therein a finely divided inorganic solid material in certain cases as desired.

It is preferable that the roofing contain less than about 2.0% of voids. Moreover, it is also preferable that the total weight of material overlying the felt base of the roofing and including the bituminous coating material and finely divided solid surfacing material be less than about 45 pounds per 100 sq. ft. so as to minimize a tendency of overlying material .to slide;

The new product of this invention may also be manufactured Without layer 82 or layer 83, for

example, to be used as the felt in built-up roofing construction. Moreover, a variety of superficial coatings of dust or granular materials, or liquids such as paint and the like, may be applied for protective or ornamental purposes, or both.

While the invention has been described in connection with certain specific illustrations, it is to be understood that this has been done for the purpose of illustration and that the invention is not to be limited thereby. Moreover, it is also to be understood that the term roofing includes roll and shingle roofing, siding strips, and other building materials of the character described.

We claim:

1. As a roofing material, a. compressible fibrous substantially completely filled and sealed web material impregnated with abituminous saturant and squeezed by pressure, mechanically applied to the surfaces on the opposite sides thereof, to a substantially devoided condition and sealed on the opposite sides thereof in said substantially devoided condition with a sealing layer of bituminous sealing material applied to said surfaces of said mechanically squeezed web which bitumi, nous sealing material has a higher softening point than the softening point of said saturant and which bituminous sealing material is integrally bonded with said saturant and with the fibers of said web adjacent to and at said surfaces of said squeezed web and fills the surface interstices of said web to substantial depth with avoidance of substantial porosity, the remainder of said web material being so completely filled with said saturant as'to be substantially free of voids, thereby affording a bituminized web which is substantially completely filled and sealed so as to be highly resistant to blistering.

2. A roofing material according to claim l, which has overlying at least one surfaceof said felt an outer layer of bituminous sealing material having a softening point substantially highimpregnated with the bituminous saturant and l er than the softening point of the saturant and has a finely-divided solid material adhering to said outer layer, the total weight of material above said surface of said felt being less than 45 pounds per 100 sq. ft. I

3. As a roofing material, a compressible fibrous lled and sealed web of felt impregnated with a. bituminous saturant and squeezed by pressure mechanically applied to the surfaces on the op-4 posite sides thereof and containing asl squeezed less than 2% of voids and sealed on the opposite sides thereof in said devoided condition with a waterproong material applied to saidsurfaces of said squeezed web without substantial absorptionpr re-entry of air, which waterproofing material has a higher softening point than the softening point of said saturant and which waterproofing material is integrally bonded with said saturant and. with the fibers of said .web adjacent to and at said surfaces of said web and illls thesurface interstices of said web to substantial depth, said web of felt as thus impregnated and sealed and including the body portion the portions adjacent said surfaces sealed with said waterproofing material being so lled with said bituminous saturant and with said waterproofing material as to contain less than 2% of voids and being highly resistant to blistering.

4. As a roong material, a. filled and sealed web of felt, said felt web being impregnated with bituminous saturant and squeezed to a substantially devoided condition by pressure mechanically applied to opposite sides thereof and said felt web being sealed in said devoided condition on the opposite sides thereof by bituminous sealing material applied to the surfaces of said web on said opposite sides thereof, which bituminous sealing material has a higher softening point than the softening point of said saturant and both penetrates the said felt and fills the surface interstices of said felt at and adjacent the said surfaces of said felt to substantial depth, said filled and sealed web containing as ay whole no more than 0.5% of voids and being highly resist ant to blistering.

HAROLD W. GREIDER. GEORGE ARTHUR FASOLD.

Images