US2036873A - Means for sealing foil wrappers - Google Patents

Description

April 7, 1936. E. A. JARECKIE MEANS FOR SEALING FOIL WRAPPERS Filed Feb. 7, 1931 IV 1 In INVENTOR Eugen A. Jure ckne i Apr. 7, 193$ Eugene it. lareckie, time d ill.

e present invention rtes to the oi cnclosing icles in wrappers of transparent toils or papers made from cellulose derivatives and relates more particularly to proved means tor p sealing such toils or papers alter the articles lit ticles are confectionery, ioodstuds such as bread,

tit cakes, crackers or meats, cigars, garments such as dresses, underwear, shirts, neckties, etc, etc. in the use oi such toil, the toll is wrapped around the article or the article is slipped into envelopes made of the toil and then the loose ends of the toil or the flaps oi the envelopes are sealed by the application of a cement, glue or other adhe sive. The use of such adhesive is objectionable as it involves a separate operation, introduces a ioreign material, oiten oi unpleasant odor, which may decompose or tegrate on standing and the seal is generally not complete along the whole ot its line. I e

To avoid the use oi an adhesive for sealing packages, it been proposed to employ toils made irom organic derivatives of cellulose, which are characteristically thermoplastic instead oi toils oi reconstituted cellulose which re not the property oi thcrmopla'sticity. Because of the thermoplastic character oi' the organic derivative oi cellulose toils, a permanent and continuous seal may be formed on the package by fusion caused by the application oi heat and pressure and without the use or any esive.

The thin sheets, tolls or papers, which it is proposed to'use, may contain any suitable organic derivative oi cellulose such as organic esters of cellulose and cellulose ethers. Examples of such organic esters of cellulose are cellulose acetate, cellulose tor-mate, cellulose propionate and cellulose butyrate, while examples of cellulose ethers are methyl cellulose, ethyl cellulose and benzyl cellulose. The foils may contain, besides the cellulose acetate or other organic derivative of cellulose, suitable plasticizers such as trlocetln, dimethyi primate, diethyl 911111818179,

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dibutyl phthalate, diethyl tartrate, dibutyl tar-= trate, etc. and any other desired materials such as pigments and efiect terials.

The thin sheets or toils containing. cellulose acetate-are preferably rendered more impervious by coating them with a solution containing cellulose nitrate or" either high or low viscosity 1o v acteristics. The-solution of cellulose nitrate is dissolved in a suitable solvent or solvent mixture which has no appreciable solvent action on the 11p cellulose acetate contained in the suriace to be coated, and this solution of cellulose nitrate preferably also contains lire retardants such as tricresyl phosphate or triphenyl phosphate and also water-resistant products such as resins and wanes. s

i found that the application oi hmt over the entire width or the lap oi" the wrapper distorted the foil near the lap and also gave the lap an undesirable cloudy appearce. Furthermore when the pressure was applied over a small area, go a groove or dent was left in the article being wrapped. Therefore, in accordance with my in vention, I apply pressure over a relatively wide area or the package being wrapped and heat along a narrow area with very satisfactory results. 25

any suitable organic derivative of cellulose may be employed as a wrapper. an i a: pic at a toll iound satisfactory for use as a wrapper was made as iollows:

Parts iii) Cellulose aceta ltd Diem], phtlhalotp 1m ll'ricresyl phosp 7 lb suitable form oi apparatus may be em- $5 ployed in carrying out invention. However, ll prefer to use a device comprising a supporting member on or into which the wrapped article is placed and a pressure member applied to be 4 mounted on the spindles oi a suitable press, the m pressure member carrying a sealing member. The sealing member consists preferably oi a strip oi 1 m" brass or copper which is insulated by hbre or other heat insulating material. The pressure member conforms substantially to the shape oi as the package being sealed and the sealing element to the contour of the lap. The element may be heated by any suitable means such as an electric heating element.

For further illustration of this invention ret- 50 erenceis had to the accompanying drawing wherein Figure 1 is a, side elevational view, partly in section of my invention as applied to the sealing of a cigar wrapper;

Figure 2 is a bottom plan view of the pressure member showing the sealing element imbedded therein;

Figure 3 is a cross-sectional view taken on line 33 in Figure '2;

Figure 4 is a cross-sectional view of the wrapped cigar;

Figure 5 is a View, partly in section, of a modificationof my invention, showing it as applied to the sealing of the flap of an envelope in which a powder-puff has been placed; and

Figure 6 is a detail view of a pressure member and a. sealing element imbedded therein.

Like characters of reference indicate corresponding parts throughout the several views.

Referring to Figs. 1 to 4 of the drawing there is shown an embodiment of my invention which is adapted to be mounted as an attachment on a cigar wrapping machine in which transparent foils or papers are used as wrappers, suitable mechanism being provided on said wrapping machine on which the attachment may be mounted. The attachment comprises a supporting member 'i for receiving a foil wrapped cigar 8 fed thereto by any suitable means and a pressure and sealing member generally indicated by the reference numeral 9 adapted to seal the lap indicated at A in Figure 4. The latter member consists of a copper bar iii to which is rigidly attached a fibre insulating member ll which should preferably be slightly wider than the cigar being sealed. The copper bar and-the insulating member are slotted at l2 and 53, respectively, to receive a brass or copper fin M, the construction and arrangement being such that the lower end contacting portion of the fin is in the plane of the working surface of the insulating member. The working surfaces of said insulating member and fin are shaped. to the longitudinal profile of the cigar in order to produce a perfect seal from tip to tip thereof. The copper bar It! is connected to a suitable heating element (not shown) and is adapted to transfer heat to the fin in such a manner that the heat will be evenly distributed thereover. It is to be understood that the temperature and pressure requirements will vary depending on the formula used in making the thermoplastic foil. If the foil is made with sufiicient plasticizer, especially if the latter is of the solvent type, such as dimethyl phthalate or triacetin, comparatively low temperatures, say 250 to 350 F., will suffice. In the case of a limited amount of plasticizer being used, or where the plasticizers are not of the solvent type, such as aromatic phosphates, then more heat and pressure will be found necessary. However, in the foil of the formula given above, I have found that the best temperature to use is from 250 F. to 350 F. and the pressure which gave the best results was from 100 pounds to 500 pounds per square inch. The time of pressing may vary from half a second to one minute.

In Figures 5 and 6, I have shown my invention as applied to the sealing of the flap ofan envelope into which has been inserted a powderpuff. The supporting member l5 and the pressure and sealing member l6 may be attached to the spindles of a suitable press. The fin l1 and insulating element l8 are curved to conform to the shape of the flap I9 of the envelope 2| and may be of any length desired.

It will be apparent from the foregoing description that I have produced a simple, inexpensive and highly efficient device for sealing a package wrapped in a thermoplastic material. However, it is to be understood that the foregoing description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of the invention.

Having described my invention, what I desire to secure by Letters Patent is:

1. In apparatus for sealing a package wrapped in thermoplastic material, a pressure member comprising a bar and an insulating member attached thereto and a heated element carried by said pressure member, the working surface of said heated element being relatively narrow in comparison with that of said pressure member and being located in position to apply heat only along a restricted portion of the lap of the wrapper.

2. In apparatus for sealing a package wrapped in thermoplastic material, a pressure member comprising a metallic bar and an insulating member attached thereto and a heated element car-' ried by said pressure member, the working surfaces of said insulating member and said heated element being in the same plane, and the working surface of said heated element being relatively narrow in comparison with that of said pressure member and being located in position to apply heat only along a restricted portion of the lap of the wrapper.

3. In apparatus for sealing a package wrapped in thermoplastic material, a pressure member comprising a metallic bar adapted to be heated and an insulating member attached thereto and a fin carried by said pressure member, said fin being adapted to be heated by said bar and having a working surface which is relatively narrow in comparison with that of said pressure member.

4. In apparatus for sealing a package wrapped in thermoplastic material, a pressure member having a working surface of substantially the same width as the package being sealed and a sealing member, comprising a heated metallic fin carried by said pressure member, said fin having a working surface which is relatively narrow in comparison with that of said pressure member and which is located in position to apply heat only along a restricted portion of the lap of the wrapper.

EUGENE A. JARECKIE.

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