US1595637A - Waterproof paper and method of producing the same - Google Patents

Description

Aug. 10 1926.

W. M. WHEILDON Filed June 16. 1921 Patented Aug. 10,

ON, OF FBAMINGHAM, MASSACHUSETTS, ASSIGNOR OF FRAMINGHAM,

WILLIAM E. WHEILD WATERPBOO This invention relates to waterproofpaw ANGIER,

Application filed June 16, 1921. Serial No. 478,138.

pers and to a method of producing the same. provide strength adaptable The more particular purpose is to a waterproof for wrapping purposes paper of substantial and yet one-which may be of relatively light weight.

applicable for producing in waterproof which are converted, that is, to the action of some mechanism or papers jected The invention is also particularly form subprocess to change their properties from those of ordinary finished paper.

invention will best be understood by reference to the following description taken in drawings,

Fig. 1 is a a method of and connection with the accompanying wherein diagrammatic view illustrating producing waterproof paper Fig. 2 is a similar view illustrating the production of waterproof craped paper.

The nature of the improved waterproof paper which forms the subject of my invention may be conveniently understood by a description of a method of making the same.

Referring, therefore, to

Fig. 1, I there show at 3 a roll of paper which is preferably of the kind known as havinga body contrasted with loose material. One face kraft or similar paper of substantial strength as felt-like and bibulous of the web 3 may be coated with a suitable waterproofing material having adhesive properties to use what is known as.

purpose I prefer and for this black asphalt, a bituminous product which is the pitchy residue of oil distillation. A

second web of paper 7 is roll and superposed of the web 3 and the two rolls 9, thus providing a duplex of squeeze led from its supply on the coated face are united by means web consisting of sheets of paper with an intervening layer of asphalt, the whole presenting at the outside clean surfaces of paper and forming an easily handled unit. The duplex web is then subjected to heat as indicated diagrammatically in Fig. 1 by the drier chamber 11 containing steam pipes 13 to such extent as to melt the fusible asphalt and to absorb it into the-body of the sheets 3 and 7.

until the asphalt coating is entirely absorbed and then readily separate two This process 1s carried on substantially the two sheets 3 and 7 and may be wound up S PATENT OFFICE.

, T0 EDWARD MASSACHUSETTS.

F PAPER ANDLMETHOD OF PRODUCING THE SAME.

separately as indicated at the right of the figure.

The resulting product is a paper which, while it may be relatively thin, is of a strong, resistant character like rdinary krai't paper and which is saturated with pitch. That is, the pitch is absorbed completely into the body an impervious layer. By saturation I do not mean that the maximum possible amount of pitch is applied to the paper. In fact the best results are obtained from the use of a lesser amount of waterproofing material giving the paper adequate water-resisting properties while leaving it non-tacky and in a condition wherein it may be readily handled. Theprocess described makes it possible to predetermine the amount of waterproofing material applied to the paper. The coating originally applied to the sheet 3 is drawn in to the body of the paper in such a way that the improved waterproof paper presents a non-tacking surface. That is, the asphalt is not on the outside of the paper in such a manner that it may stick to or smear adj acent articles on which the paper is used.

My invention is particularly applicable to the production of papers which are in some way processed and, in particular, where this process entails a wetting of the original finished paper the results are particularly advantageous. Thus in Fig. 2 of the drawing I there show diagrammatically the production of waterproof craped paper of a nature similar to that described in Fig. 1 but also provided with crapes to render the same expansible and elastic. The two webs of paper 3 and 7 as before are united by an intervening layer of asphalt. The completed' duplex web may then be passed through the saturating bath 15 of a craping machine of ordinary type, caused to adhere to the craping roll 17 and while adherent thereto crowded back on itself by the doctor blade 19, the moist Web being craped by the action of the doctor in well known manner. The moist craped web then passes to the drying chamber 11. The web is dried and the crinkling made permanent but the heating is continued as before in such manner that the asphalt is absorbed completely by the paper so that the webs 3 and 7 may be separated, Cilk'll as a single crapcd thickness of paper efficiently waterproofed.

- it offers no resistance to the softening of these outside webs by the saturating, bath 15 inorder to make the paper fit for craping. Thereafter the necessary drying step for drying the craped paper is combined with the heating which causes absorption of the asphalt with resultant economy. The soaking of the paper for craping purposes also opens the pores thereof and renders it more penetrable' by the waterproofing pitch which is later absorbed into the same.

are treated with the same.

The material produced by the process illustrated in Fig. 2 is a single thickness of strong paper, Waterproof but having a nontacking surface which is irregularly craped. The rough surface of ordinary craped paper causes difficulties if it is attempted to Waterproof the material after craping. In

' the present instance the asphalt is uniformly applied to the uncraped sheet and all parts On the other hand, if a single sheet of uncraped material were effectively waterproofed, it would resist the softening action of the bath 15 of the craping machine or this bath would adversely affect the waterproofing material and perhaps cause it to run and smear and gum the 1 machine parts. In the present instance this does not take place and the two webs 3 and 7' absorb the waterproofing material after they have been craped, which waterproofing material'has been applied before the craping operation in such a manner that it does not adversely affect that operation.

- way of example in the accompanying draw- "ing, what I claim as new and desire to se- Having thus described in detail the particular'embodiment'of my invention shown by cure by Letters Patent I shall express in the following claims. Claims 1. A waterproof paper consisting of a crinkled base impregnated with pitch and having a non-tacking surface. v

2. The method of preparing craped waterproof paper comprising connecting two layers with fusible adhesive waterproofing material, wetting the duplex layer and craping the same and then heating it to absorb the material in the layers and separating them.

3. The method of preparing in waterproof form sheet material which is finished by a process involving wetting the same characterized by joining two layers of unprocessed sheet material by fusible adhesive waterproofing material, processing the assembly and then heating them to absorb the waterproofing material into the layers and separating them.

4. The method of preparing in waterproof form paper which is converted by the action of mechanism thereon characterized by joining two layers of unprocessed mate rial by waterproofing adhesive to rovide a duplex unit which may be handled by such mechanism without smearing or gumming of the same, processing the duplex unit, and therafter absorbing such adhesive into the layers and separating the same.

5; The method of preparing paper having bituminous waterproofing material absorbed into the body thereof comprisin assembling two sheets with said WVEIIBIPIOO material interposed and heating the assem ly to absorb the material into the sheets.

6. The method of preparing paper having bituminous waterproofing material absorbed into the body thereof comprising superficially coating a sheet with such material, applying a second sheet thereof and heating the assembly to absorb the material into the sheets;

In testimony whereof, I have signed my name to this specification.

WILLIAM M. WHEILDON.

Images