US2203173A - Felted fabric sheet - Google Patents

Description

' "NoD'l-awing.

I 2 Claims.

s,inven on relates to a felted sheet and arly'Ipe rtains 'to'.,a"felt sheet fabricated rigs a lfurjriishlpiilpstock which felts in a soft, porous shearer 'high ab'sorptivity which may readily, be. impregnated with a suitable water- 'oofii lg f,InaterialLLWhen the sheet is desired .be'fmorejrig'id in character the waterproofing l ed in preferably hard','thereby stiffenlng andr'igidifyi'n'g' the felt 'fo'u'ndation which it 'mpregnates. The impregnated sheet isreadily iaptedftojbe embossed with any suitable decorae esign and may also advantageously have a JV? finishing layer such as a paint or r --'sui t'able 'material applied to one or both e. sides. H v

More' specifically described, the invention is typified by felt material composed of waste paper, suchas newspapef'ahd the like, waste and manufactured flock and refined wood pulp having an alpha-cellulose content in excess of 93%. These ingredients are pulped in suitable proportions to provide a furnish stock, and then the stock is felted in a water laid web of felt which web may be subsequently impregnated with a suitable waterproofing material. The waste paper material includes all refuse and waste paper material such as newsprint and the like, and may advantageously compose the predominant proportion of the furnish stock. A sheet composed entirely of or nearly all of waste paper material is relatively compact and dense and not of a porous character suited for being highly absorptive to a waterproofing material. Accordingly it is not particularly suitable for being impregnated, especially where a large quantity of waterproofing material is to be impregnated in the web. Because of this, waste paper material has had only a limited use, and then only in small proportions with other materials as a cheap filler. It has been found, however, that a furnish stock capable of being felted into highly absorptive sheets, may be composed of a predominant proportion of waste paper material by having certain other material associated therewith in subordinate proportion. One material suitable for combining with the waste paper material is typified by flock materials which are recovered in several of the manufacturing processes through which textile fabrics must pass in finishing. There are two types of flocks: those resulting from scouring, fulling, raising, brushing and shearing of woolen'fabrics. The others are those resulting from rag grinding and tearing in the preparation of reclaimed wool. The difference between these 55 two types is that one is waste or refuse material 2,203,113 "FELT ED FABRIC SHEET I WilliamJ. Moeller, Mount Healthy, Ohio, assignor'lto-The Philip Carey Manufacturing Com- ,pany, a-corporation of Ohio I I Application September 6, 1935, Serial No. 39,497

- in vcombintion with waste paper material for the manufacture of felt sheets. Another material suitable for combining with the waste paper material is refined wood pulp having an alpha- I cellulose'content in excess of 93 This refined wood pulp is attained by treatingalpha-wood fibre with. an alkali refining material. For example, chemical wood fibre such as sulphite pulp I may be subjected to a series of treatments with chemical reagents including atreatment with alkaline liquor which serves to dissolvef rom such wood pulp non-alpha-celllulose components such as less-resistant celluloses, ligno-celluloses and resins to produce a fibre stock having an alpha content of about 93% or greater. Alpha wood fibre is preferably felted in an unbeaten or lightly beaten condition and has greater freedom from fibre fragments and colloidal cellulose as well as from hemi-celluloses and resins than unrefined wood pulp of the character of sulphite kraft or the like. The usual commercial sulphite has an alpha-cellulose content of about 87%. The addition of the flock and the alpha-cellulose content of the character described gives the felt a high degree of porosity and absorptivity whereby same may be impregnated with a bituminous saturant, such as asphalt or the like, to about 155%, by weight of the saturant. Moreover the sheet is particularly strong and by using an impregnating material which is hard, the felt base may be rendered substantially rigid and boardlike in character. Ordinarily felts which are used as a foundation sheet for. waterproofed panels, roofing and the like, are impregnated or saturated with bituminous compositions which are usually soft in consistency, having a penetration of not greater than at F. and a fusing point by the B. and R. method between to F. These saturating compositions are ordinarily employed merely to saturate and waterproof the foundation felt and without materially affecting its physical character. They are not of a character to stiffen or rigidify the foundation sheet. It is one of the aims of this invention to give to the felt a hard and rigid character to provide a substantially hard rigid body, and in order to effect this, the felt is saturated with a special hard waterproofing composition. A suitable saturant is typified by an asphalt composition blown to a penetration of 3 to 5 at 77 F. and having a melting point over mercury of from 200 to 230 F. This asphalt impregnating composition is made especially hard to give the felt foundation rigidity, hardness and waterproofness after impregnation. It is sometimes referred to as combining asphalt and is considerably harder than bituminous compositions commonly used for impregnating fabrics. Impregnating materials other than asphalt may be employed for saturating'the felt, and rubber may be referred to as such. Sheets impregnated with the hard impregnating material are particularly adapted for lining automobiles such as under the dash, doors, bottom sides of seats and the like and may also be used for panels or linings for facing any rigid or semi-rigid base. They may be used in single ply or several of the plies may be adhered together by an adhesive layer or an adhesive layer of the same hard character as the impregnating material in order to further rigidify and stiffen the laminated or composite sheet. Or instead of having all the plies of the character of felt material herein described, laminated or composite sheets may be provided in which the felt sheets of the character herein described are employed as the facing or exposed sheets having a core of different character. For example, a center ply or plies of light kraft paper may comprise the "core and have applied to opposite sides thereof facing sheets of'felt of the character above described. The impregnated felt sheets being substantially rigid by reason of the impregnating material are adapted to be embossed for decorative purposes. Also the felt sheets whether embossed or not may be decorated by having a suitable decorative material such as paint applied thereto. A water paint is particularly advantageous and one coat thereof applied at the time of. manufacturing the saturated felt conditions same for ultimately finishing with fewer coats of finishing paints..

As one embodiment typifying the inventionand' illustrating preferred proportions of the components of the furnish stock, a felt sheet may be fabricated composed of about 75% newspaper material, about carpet flocles'and about of the refined wood pulp having. an alph'a cellulose content of about 93%. These ingredients are reduced to a furnish pulp stock in a'con ventional beater and may then be felted on" any suitable Fourdrinier or cylinder machine which is used for fabricating felt. The furnish stock is then impregnated with waterproofing and finished by embossing and/0r painting. The sheet is particularly suitable in the manufacture of automobile bodies and other similar uses where shrinkage is limited .within certain specifications. v

While ,I have described one embodiment of the invention in detail for the purpose of illustration, it will be understood that there maybe various changes without departing from the, spirit thereof,' particularly as to the proportions"v of the different materials composing the felt.

I claim:

1. A waterlaid web of felt composed of furnish stock comprising'about 75% newspaper, about 10% flock derived from woolen fabrics, and about 15% refined wood pulp having an alpha-cellulose v30 content in excess of 93%.

2. A waterlaid-web of felt composed of furnish stock comprising about 75 newspaper, about 10% flock derived fromwoolen fabrics and about.

15% refined wood pulp having an alpha-cellulose content in excess of 93%, said felt being impregnated with a waterproofing material;

WILLIAM J.-MOELLER.