US2043135A - Method for sealing paper cartons - Google Patents

Description

June 2, 1 936. A. yvEsELMAN 2,043,135

METHOD FOR SEALING PAPER CARTONS Filed Nov. 4, 1932 Alberi wax/mu IN VENTOR BY I Q A TORNEYS ucts, especially food products, for mechandising' Patented June 2, 1936 UNITED STATES PATENT OFFICE METHOD FOR SEALING PAPER CARTONS Albert wesselman, Cincinnati, Ohio Application November 4, 1932, Serial No. 641,198

8 Claims.

The present tendency to package various prodthe same to the retail trade presents various problems, one of which is the sealing of the contents of the package or container in such manner that moisture from without shall not enter, that moisture from within shall not escape, and various other .problems because of which it has been deemed necessary and desirable to use sheet metal containers and the like in numerous instances. For'reasons of economy paper or cardboard packages are desirable as compared with sheet metal containers and the like, and because of that fact various improvements and treatments of paper and cardboard have brought the cardboard art to such a place that an ordinary piece of cardboard may be rendered substantially impervious to moisture, air, and vermin. Practical problems, however, have interfered with the satisfactory commercial use of paper and cardboard containers that are so treated because the producer and packer of various products in cardboard and paper containers has been unable to provide an effective seal at the time the carton or package is closed upon the contents thereof. Because of this condition, there has grown up the practice, particularly common in the breakfast food art, of providing an inner waterproof container, generally having a parafiine coating or impregnated withparafline whereby to provide a substantially sealed inner container which in turn is placed in an outer container and which outer container is not sealed against moisture, atmosphere, etc.

An object of this invention is to provide a means and method for accomplishing in one container, the same result that is attained in the two containers referred to in the preceding paragraph, as being a common expedient in the breakfast food art. Y

Another object is to provide a simple and emcient solution of the problem that will readily fit in with the present commercial practices and which will not in any way interfere with or delay the packaging and handling of goods.

Although the remarks heretofore made are directed primarily to the packaging of food products, it is to be understood that reference to food products is merely exemplary and is not made for the purpose of restricting the invention to that particular field or activity.

These and other objects are attained by the invention described herein and disclosed in the accompanying drawing, in which:

Fig. 1 illustrates in perspective the ordinary or common rectangular carton or package in which various products are quite commonly packed at the present time. I

Fig. 2 is an enlarged side view showing one of the ends of a closed package such as illustrated in Fig. 1.

Fig. 3 is an enlarged sectional view online 3-3 of Fig. 2.

Fig. 4 is an illustrative view of one simple arrangement of mechanical devices that may be used in connection with the invention.

The carton lilexemplifles any kind of a paper box that has been treated with any of the various preparations for rendering the material thereof impervious to moisture, atmosphere, and the like, and may be suitably treated so that such vermin as would be expected to attackthe material or the contents of the finished package, would retrain from such act. The package l0 would be filled with the articles or product that it is intended to carry into the market,'and the various flaps l I, I2, I3 and I8 would be folded upon one another and would be sealed or glued together as is common practice at the present time in closing cartons or containers of the character described. This closing of the ends of containers is done by machinery or mechanical means at a rapid rate and as a result thereof substantial openings or crevices result. It is not uncommon to have an opening at one or more of any of the eight coro ners of a container such as illustrated in Fig. 1, and through such openings atmosphere and dust may pass.

After the package has been closed in any suitable manner, for example as explained, the containers are sprayed with a quick-drying material that functions both as an adhesive and as a plugging or sealing substance. This spraying is accomplished along the cartons between the indicated eight corners. The manner in which the flaps II to M, inclusive, are turned in upon any particular type of carton will determine the places and the extent upon which the spraying should be done. Ordinarily in cartons wherein the smaller flaps such as I3 and M are turned in first, and over which larger flaps I l and i2 are then turned in, it would be sufl'icient to spray the closed container along the crevices developed at the upper and lower extremities of the narrower sides I 5 of the carton, incident to the indicated folding in of the flaps. In some instances the nature of the stock from which the carton is made is such that the mere bending over or turningdown of the flaps such as l l to Hi inclusive, effects a breaking down to some degree of the paper stock or card- 55.

board stock. and through such weakened or broken down portions thereof, it might be possible for air, dust and/or moisture to find their way into and out of the container. In instances where this may happen, the cartons 'or containers are preferably sprayed all around the upper and lower extremities of the carton at which places the various flaps are hingedly connected to the various body panels such as l5 and i6, of the carton.

The material used for the indicated purpose may comprise any suitable materials in view of the nature of the paper or cardboard stock from which the container is made and in view of the nature of the articles or substances to be contained therein. In connection with containers used for food products, a material of a nitro-cellulose base may be used, and with the same there may be employed a suitable solvent as in one of the number of alcohols that will permit ready spraying of the composition through any of the commonly employed spray devices such as spray nozzles. Without limiting the use to any particular device or type of spray device but merely for the purpose of indicating generally types of spray device that may be used for this purpose, reference is made to such patents as De Vilbiss, No. 1,045,266, Day, No. 1,321,014, Wold, No. 1,169,587, and ohers. In some instances it might be desirable to provide an air current used in connection with the atomizing devices which is so conditioned that the sprayed material will dry almost instantaneously with contact thereof with the container. Spray devices of the character referred to are indicated generally by nozzles I! in Fig. 4. It may be desirable in some instances to apply a slight pressure upon the ends of the containers at or about the time the sprays are directed along the crevices of the container thereby holding the various layers of overlying flaps in position so that the sprayed material may function most efficiently as an adhesive for holding the layers together and thereby reducing the quantity of material necessary in order to effect an effective sealing and plugging of the indicated crevices. Such pressure means may be of any suitable character and for purpose of general illustration of a simple means for accomplishing the indicated purpose, there is shown a pair of cooperating belts i8 and I9 that jointly serve to convey or carry the containers past the spray nozzles l1 and for exerting sufflcient compressive force upon the containers to attain the indicated pressing together of the flaps at the time the sealing material is applied. It is to be understood that any other mechanism for accomplishing similar results may be supplied in lieu of the belts l8 and I9 and that nozzles may be placed in other positions than those shown, it being obvious that if a spray is to be directed around the upper and lower extremities of the four walls l5 and it, that a different arrangement of belts and nozzles may in some instances be necessary. The discharge of sealing material from the nozzles may be controlled by the articles as they are carried along by the conveyor whereby the nozzles efiect discharge only at such times when a package is in position for treatment.

In Fig. 3 the sealing material is illustrated as indicated at 20. It is to be understood that with different packages a different relationship of crevices and iiaps will exist and it is intended that the spray shall be adequate to plug up all of these various openings and that the spray material shall supplement the binding or retaining function of any of the various other adhesives that may be used in the first instance for closing and adhesively securing the flaps Ii to H inclusive. In some instances the entire adhesive agent used for holding the flaps in position may be applied by sprays, however, generally this arrange ment would not be feasible in any instances where the nature of the spraying material might injuriously affect the contents of the container in the event that some of the material should be blown into the container before the flaps are brought down into folded position as illustrated in Figs. 2 and 3.

At the present time it is quite common to provide a so called gloss finish to containers. and the spray material may be of such composition that when applied it will give a similar gloss effect to those parts of the containers that are sprayed. In some instances where the containers do not have the gloss finish on the outside, it may be desirable to use a spray material that will not give a gloss effect when applied to the container. At the present time paper containers, especially cardboard containers are somewhat extensively coated upon either the inside or outside, and in some instances both inside and outside for obtaining a container that is substantially impervious to moisture, air, etc. and the spray material must of course be such that it will not counteract the indicated treatment as well asbeing of a nature such that it will readily adhere to the painted container regardless of the treatment thereof. Moreover, the spray material should be of such character I that when dry, it is still somewhat elastic, it being obvious that if the material should be too rigid when applied, the accidental dropping of cartons might fracture the seal and thereby defeat the attainment of the objectives of the invention. Generally various lacquers meet this requirement. 'There are many varieties of lacquers and the various characteristics thereof are quite well known wherefore it is to be understood that such lacquer will be used as will give the desired degree of elasticity while at the same time attaining the adhesion and plugging effects.

What is claimed is:

1. The method of sealing fieidble containers comprising folding parts thereof upon one another for effecting a substantial closing of the container whereby crevices are developed adjacent the folded parts and then blowing a sealing and plugging material into the crevices.

2. The method of packaging products in paper and other fibrous containers having foldable parts between and along which parts, crevices do or may develop incident to the folding operation, and comprising the folding of parts of the container, whereby crevices are developed along the folded parts andthen spraying a substantially atomized substance of adhesive and cohesive characteristics into and along such crevices for closing or plugging the crevices and for holding the container parts together.

3. The method of closing and sealing cartons and the like comprising foldable flaps, and consisting of folding and adhesively securing the fiaps to close the container about the contents thereof whereby crevices are formed adjacent the folded parts and then applying a spray of material of adhesive and cohesive characteristics along the foldable flaps for sealing or plugging the crevices developed incident to the folding and initial securing operations.

4. The method of initially folding and adhesively securing together foldable parts of a container whereby crevices are developed at the surface of the container and adjacent said folded parts and then applying plugging and sealing adhesive material along the crevices incident to said folding and securing operations, and apply-" ing pressure to the container alongside of said crevices during the plugging and sealing operation. a

5. The method of treating containers having flexible parts folded upon one another whereby crevices are formed at the surface of the cont'ainer and adjacent to said folded parts, comprising the steps of applying an adhesive crevice filler along the crevices at the lines of folding of the said folded parts, and applying pressure to p the flexible parts to contract the crevices during and after application of the crevice filler.

6.vThe method of sealing flexible containers comprising folding the parts thereof .upon one another for effecting a substantial closing of the container, whereby crevices result adjacent to the folded parts, then directing into the crevices an adhesive filler in a form which dries almost instantly upon contact with the container so as to enter the crevices without materially entering the container interior.

"I. The method of sealing flexible containers comprising foig the :w thereof upon one another for effecting a substantial closing of the container, whereby crevices result adjacent to the folded parts, then directing into the crevices an adhesive filler in a form which dries almost instantly upon contact with the container so as to enter the crevices without materially entering the container interior, the method including also the step of applying pressure to the folded parts during application of the filler whereby to further reduce the likelihood of filler entering the container interior.

8. The method of manufacturing a container, which comprises producing from a fibrous sheet material treated for exclusion of moisture, air, and vermin, a container body having foldable end closing flaps, folding the flaps upon one another whereby to form crevices at the surface of the container and adiacent to said folded parts, and applying a quick-drying adhesive filler at and about the folded end closing flaps, to dispose the coating between and about the adjacent folded end closing flaps and sealing the crevices and the interior of the container against entry of external air, moisture or vermin at the places of fold and overlap of the folded end closing flaps.

ALBERT WESSELMAN.

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