Patented May 16, 1933' UNITED STATES PATENT OFFICE LOUIS P. NEW YORK, 11'. Y WILLIAI P. OI HILLSIDE, NEW JERSEY GIG-BETTE AND CIGARETTE PAPER IANUIACTUBE Io Drawing." Application filed June 18,
Our present invention relates generally to paper manufacture, and has particular reference to cigarette paper.
A eneral object of our invention is to provide a new and improved type of cigarette paper, produced or treated by means of a novel procedure, whereby the paper may be imbued with useful. properties and qualities which are lacking in the ordinary cigarette paper now almost universally used in the manufacture of cigarettes.
It is a primary object of our invention to provide a cigarette paper which is waterresistant.
Cigarette paper consists essentially of cellulose. Paper pulp of requisite purity, suspended in water, is formed into thin webs or sheets, usually on the well-known type of Fourdrinier machine; and the webs are then subjected to dehydration, drying, and calendaring. One of the essential characteristics of the finished product lies in its porosity, since it is thisporosity which permits the products of combustion to escape when the 23 cigarette is smoked. To improve the burnin qualities of the paper, a filler such as calcium carbonate is sometimes employed, serving to increase the porosity of the paper and enhancing not onl its opacity but also its continuity of smoot burning.
The inherent porosity of a good cigarette pa or is obviously accompanied by reat absor ency, which is an undesired qua ity in so far as it results in almost complete or immediate breakdown or disintegration of the paper whenever a drop of water comes in contact with it. This disadvantageous characteristic of ordinary cigarette paper is wellknown to those who have experienced the 40 almost complete ruination of a cigarette when it is subjected to a drop of rain or the like;- or, more commonly, when the tip of the cigarette becomes wetted upon insertion into the mouth.
Any attempts to obviate the foregoing disadvantage by any ordinary type of impreg nation proceduce, with a view to producing a aper which is waterproof, is obviously uneasible, and has roven so in practice, for
the reason that t e porosity 'of the paper 1982. Serial No. 817,600.
must be maintained in order to insure its burning qualitites. Accordingly, the problem has been sought to be solved in a variety of ways involving the formation or addition of special tips on the cigarette, such as 56 cork, straw, or the like. In some instances, we are aware of attempts to produce tips by forming the same of cellulose nitrate.
Tipped cigarettes are, however, notoriously disliked by the average smoker. Not only 60 is the addition of a separate element a procedure which raises the cost of manufacture and the selling price, but it produces a cigarette which is distinctively different from the ordinary run of cigarettes, a distinction which for some reason or other does not appeal to the public generally. Furthermore, all tips of conventional character are utterly unburnable without a highly disagreeable and sometimes toxic effect. Our present invention is predicated upon the discovery that it is possible to treat a cigarette paper by a process which essentially of the nature of impregnation or coating, and which results in imparting a waterresistant characteristic or quality to the paper, and sometimes other desirable characteristics, without inthe least impairing the inherent porosity, appearance, taste, or burning qualities of the, paper.
It is a feature of our invention to produce or treat cigarette paper for the purposes illustratively specified by a procedure wherein the advantages of the phenomenon known as blooming or efliorescence are resorted to. This phenomenon manifests itself in a variety of arts and under a'variety of conditionsvand consists essentially in the formation, either on the surface or throughout the body, of a whitish or colorless, mealy or crystallme powder or crust caused by some sort of chemical action or evaporation under certain specified conditions. Ordinarily, the phenomenon of blooming is an undesirable one and is usually strenuously avoided or sought to be avoided, especially in processes involvingthe waterproofing of paper or similar material.
We have, however, discovered that a waterresistant material may, under certain condi- 15 resins.
55 the general class which includes tions, be caused to form a desirable type of efliorescence on or in cigarette paper in a manner whereby the inherent porosity and burning qualities of the paper are substan- 5 tially unimpaired while a new and additional water-resistant characteristic, and other desirable characteristics,"are imparted to the aper.
Although our invention is, from many aspects, not restricted to the employment of any particular type of water-resistant material, we have found it preferable and eminently satisfactory to employ a material of the class which may be generically designated as Resins are insoluble in water, and yet they are soluble in organic solvents, which ermit our method and mode of treatment to e economically and feasibly carried out in a commercially practical manner. Of primary importance is the fact that resins generally are amenable to the blooming phenomenon, and are readily adapted to form an efliorescence of a porous character.
Brlefly, our invention res1des 1n applying to a cigarette paper a resin dissolved in a solvent which may be evaporated under conditions inducing the formation of an efllorescent film of the resin on or in the paper'; and thereupon causing thesolvent to evaporate under the proper conditions to effect this purose. We have found that our present obective is most satisfactorily carried out by dissolving the resin in a readily volatile solvent, e. g., of the class which includes carbonv tetrachloride, benzol, acetone, alcohol, and
similar materials; and by permitting or causing the solvent to evaporate rapidly in a moist atmosphere. While we do not mean to restrict ourselves to any particular explanation "of the nature of causes of the phenomenon which results, it is our present theory, based upon extensive experimentation and study,
that the relatively rapid evaporation of the solvent reduces the temperature of the atmos- 4'5 phere in the proximity of the paper, thereby increasing the relative humidity in the vicinity of the resin, and thereby causing the resin to precipitate or bloom upon and in the pores of the paper, producing a porous film or efllorescence which imparts remarkindene, etc;
way of illustration, we will state that one method of producing or treating a ciga-" rette paper in accordance with our present in-- vention lies in first forming the paper in the usual manner; then subjecting it, as by iming takes less than a minute, and is carried out in an atmosphere which is purposefully prevented from being overheated or dry. The resultant paper looks and feels exactly like the untreated ordinary paper; its burn ing characteristics are substantially unimpaired; and yet the paper has the remarkable quality of resisting the penetration or absorption of water, an advantage whose importance can hardly be over-estimated and which ear-marks the product as a new, different, and hitherto unattained thing.
We have found it equally satisfactory to treat the paper with the resin solution by coating the paper on one or'both sides with the material, as well as by immersing it into a bath of the material. Accordingly, although the immersion procedure is preferable, it will be understood that our inven tion may be carried out with equal facility by applying the resin solution by a coating procedure.
Our invention also contemplates the employment of resins, such as the oleoresins, which carry with them certain essential oils or similar ingredients of aromatic ualities. It is possible, for example, by emp oying a balsam resin to produce a cigarette paper, and a finished cigarette, of new and improved aromatic qualities, the term aromatic referring not only to odor but also to taste. The water-resistant characteristics are achieved in conjunction with a property causing the cigarette to embody a pleasing and novel aroma and/or taste when it is smoked, thisresult probably being due to the fact that the essential oil or similar ingredient is released under burning conditions.
Under certain circumstances, we have:
found it advantageous to employ a small percentage of a waxy substance, such as paralfine, carnauba wax, cerowax, or the.
like, in conjunction with the resinous substance. For example, in the formula here inbefore illustratively specified, about two parts, by weight, of parafline may advantageously be added, the wax in some way seeming to enhance the practice of the proc-' ess and the water-resistant resultant paper. I
It will also be understood that we deem a qualities of the finished cigarette consisting of a rolled body present invention to fall within the purview of our invention.
The term efiiorescence, as the same is used herein and in the appended claims, is intended to signify the henomenon hereinbefore referred to where y the resin apparently forms a film or layer of porous character on the paper, although it will be understood that the resin is quite possibly in efliorescent condition within the pores of the paper as well. Stated otherwise, it is our contention and belief that the resinous material is impregnated in the paper in a mild manner, the amount of resin being insufiicieht to affeet the porosity and burning qualities of the paper, yet enough to impart a water-resistant characteristic to the paper. It will be understood, however, that the impregnation referred to is not of the ordinary character wherein the pores of the paper are filled and whereby the porosity is seriously impaired, if not completely destroyed, but that the deposit of the resin either on or in the paper is of the character which is the result of a blooming or efllorescence whereby a broken and porous or powdery deposit results.
In general, it will be obvious that changes in the details herein described for the purpose of explaining the nature of our invention may be made b those skilled in the art without departing rom the spirit and scope of the invention as ex ressed in the appended claims. It is there ore intended that these details be interpreted as illustrative, and not 3. The herein-describedmethod of treat ing cigarette paper to make it water-resistant, which consists in forming thereon a porous efllores'cence of resin and a waxy substance.
4. The herein-described 'method of treattile solvent, and causing the solvent to evaporate in a moist atmosphere.
7. The herein-described method of treating cigarette paper which consists in a plying to it a resin of the class which inc udes mastic and ester gum, said resin being dissolved in a readily volatile solvent of the class which includes carbon-tetrachloride, acetone, and benzol, and causing the solvent to evaporate under conditions inducing the formation of an efilorescence of said resin on the paper.
8. The herein-described method of treating cigarette paper which consists in a plying to it a resin of the class which inc udes mastic and ester gum, coumarin and indene, together with a wax substance of the class which includes para ne, carnauba wax, and cerowax, said resin and waxy substance being dissolved in a readily volatile solvent of the class which includes carbon-tetrachloride, acetone, and benzol, and causing the solvent to evaporate under conditions inducing the formation of a porous efilorescence of said resin and waxy substance on the paper.
In witness whereof we have signed this specification this 13th da of June 1932.
LOUIS P. SC ITZER. WILLIAM P. SCHWEITZER.
ing cigarette paper to make it water-resistant, which consists in applying to ita waterinsoluble material dissolved in a solvent and adapted to eflloresce on the paper when the solvent evaporates.
5. The herein-described method of treating cigarette paper to make it water-resistant, which consists in applying to it a resin dissolved in a solvent, and causing the solvent to evaporate so as to deposit an efllorescence of said resin on the paper.
6. The herein-described method of treating cigarette paper which consists in applying to it a resin dissolved in a. readily vola-