US2381590A - Shoe stiffener - Google Patents

Description

Aug. 7, 1945. w. H. HEATON 2,381,590

SHOE STIFFENER Original Filed May 10, 1943 bri Patented Aug. 7, 1945 inas tentt "e fthefabr cin a liquid bath or 'tl atur td a fit, an 1111811, n-

derit to compact theb'ody of the sheetfand "o forma fipishedsunfacethereon.

T have discovered'tha't the process of manufacture may be expedited, its expense reduced, and a superior type of stiffener material produced by calendering the dried saturated sheets two at a time in overlapping condition. Two sheets,

calendered in this fashion form a partial cushion for each other with the result that the inner surface of each sheet presents relatively rough and porous texture while the outer surface of each sheet has a relatively hard and compact finish. From the manufacturing standpoint, therefore, it will be seen that this procedure reduces the time and expense of the calendering operation substantially by one half.

The sheet material of my invention has the property of ideal absorption for its' intended use, that is, of very quickly taking up just the right amount of solvent needed for properly softening it for th lasting operation. A box toe blank to be satisfactory must conform to very exacting requirements in respect to its condition'ing behavior or temporary softening preparatory to the lasting operation. For example, a box toe blank calendered on both sides is slow in conditioning, with the result that the laster has to Wet up six or eight blanks ahead of time in order to allow each blank to become properly softened by the time he is ready to use it. Then, if he has any unusual difficulty with the lasting of a particular shoe and his routine is delayed, the wetted blanks are likely to become dry and stiff again before he reaches them. Various expedients have been tried in order to shorten the time of conditioning, as by pricking or steaming the blanks, but even at the cost of such supplementary operations the results have not been satisfactory. On the other hand, if the box toe mauve; st ip at s liqlJ-idf-ljo'm t e {y PATENT; (-1 1- wsiternunssm m nnm; Mass. f g

halts-i3. sat a: I

186,321. Divided and tm 'antlic attice eaw ua;

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iniatenal'is not calendered it will absorb too much sbfteriing solution, become and r'fulrc'uit to likely to 'sfta'in thefupper leather and troublesome because the saturant tends to i'tranisjferfjtp jtheoperator's fingers. The sheet stiffener material produced in accordencewith the present invention, however, is extremely satisfactory from all these standpoints; The operator, canfwet up each box toe blank as "he 'jcomes tofi'tfandjfind it immediately conditioned "forla'sting.

Another advantage of the present inventicnis [in connection with the manufacture of unlined shoes where ijtfis desiredto cement the "dry box it'o'e'blanksj'tolthe inner surface of the upper or vamp for example." Shoes having s'erni-fshft boxes 'arefr nad'61injt'hisway. {Heretofore cement has to med an unsatisfa'ctory bond with the calenilered surface of box toe material, but the rough porous surface produced by the process of the present invention furnishes a particularly good bond for cement so that the blank may be quickly and securely attached to the upper before it comes to th laster.

These and other features of the invention will be best understood and appreciated from the following description of a preferred manner of practicing the invention in producing improved shoe stiffener material for box toe blanks, all as illustrated in the accompanying drawing. in which Fig. 1 is a diagrammatic view showing superposed sheets passing the calender rolls, and

Fig. 2 is a fragmentary view on a greatly enlarged scale of a piece of stifiener material.

The base material employed may be doublenapped flannel 0.90 to 1.60 yards per lb. The first step of the process is to saturate a continuous web of this flannel by running it through a bath of lacquer which may comprise cellulos acetate or cellulose nitrate scraps dissolved to produce a mixture of thin consistency in acetone or Methyl-Cellusolve" or other commercial solvent. Upon leaving the lacqer bath the web is conducted vertically, passing between stripper rolls which remove excess solution and then is drawn slowly in a circuitous path until substantially but not completely dried. It is then cut in sheets of convenient dimension, for example 36" in length, and two of these sheets are then stacked in superposed relation and fed through calender rolls with suitable setting. A single ply of saturated and dried fabric may run from 0.060 to 0.120 inch in thickness'and for calendering two sheets of such stock the rolls .be 'g h easier; mob i t f' ls ai formedby thedirectengagementof the calender 25 sorb liquid solvent and bond flrmlyjto cement,

' [Another advantage of my improved process is are solcomlpact'asl to' pr'eve nt' the 'proper absorp- I tlll of solvent in the conditioning step. By my 35 vent, the blank as a' ,whole' being limiteddn its improved proces however, one surface must of irregularities in the manufacturing proare set for 0.090 to 0.160 inch. The sheets leavcedure. Cellulose acetate and cellulose nitrate ing the calendering operation will be 0.045 to are the best stiflening compound in the form of 0.080 inch in thickness. The surface next the a colloidal dispersion now known to me for purcalender roll on each sheet has imparted to it a poses of my invention but I contemplate the emrelatively hard, smooth and compressed appearployment oi. any other cellulose derivative having ance whereas the inner surfaces of the sheets their characteristics. which contact each other remain relatively rough, The present application is a division of my prior porous antitspongy with-a mat application Serial No, 486,321, filed May 10, 1943,

In Fig'xl'lathe.novel-..calendering step of my wherein I have claimed the method herein disprocess is suggested. Two superposed sheets l2 l0 closed of making shoe stifiener material. and I3 are shown as passing through the calender-1 :1 Having thus disclosed my invention and derolls in and II, The sheets 12 and I3 have been scribed in detail one manner of putting it into prepared as above described and are presented to practice I claim as new and desire to secure by the calender rolls substantially ;.dry., butxcon- Letters Patent: taining a small residue of solvent. The inner 15 1, Shoe stiffener material comprising a double surfaces of the sheets I2"'an d"l 3 "H1850tO gBtl'lCl-i ff nappedflannel saturated with a colloidally disas the sheets pass betweentherollswhileftheir persedstiifening compound and having a relaouter surfaces are subjected to direct ir'o'nin'g' tively rough mat-finished surface on one side engagement of the rolls. In Fig. 2 a. fragment and having its nap laid down in a relatively of, the finished sheetmateriaris indicated on a smooth compact surface onthe other side. eatl magn fie Se l? porous spongy surface ,wh

2. A box toe blank comprising a fabric'base impregnated with a colloidally 'dispersedstiflening compound and having one mat finished surface which is spongy and which'will quickly abthe surface l5 being the i ichhas been cushioned in the lcalend'e'rihg operation and the surface the other surface being'ironed smooth and relatively slow in absorbent capacity. I

3. A box toe blankcomprising a woven fabric that itjobviates an danger or Spoiling the stock base impregnated with a colloidally dispersed b'yover- 'doing the,calenderingloperatibri; It has p b heretoff' t by toocl'ose setting of stiffening compound. selected from the group, the calender rolls or by calender ing the stock while :it' contains [too much r esidual sowent surfaces cellulose acetate and cellulose nitrate and having v v one surface which is relatively non-absorbent, havejbeen rqrmjed m the finished material which firm andcompact and the'other a mat finish sur- "face spong'y'and' highly absorbent of liquid sol- I absorbent capacity by lit's 'saicl compact surface necessity be'po'rous' andabsorbentjregardless of portion. 0 I V j H. HEATON.

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