Strip-gummed paper and process of making same

Application filed October 8, 1924, Serial No. 742,375. . Renewed December 14, 1923.

In the manufacture of labels, posters, and the like, it frequently is desirable to have only the opposite margins or some other relatively small area of the label or poster B gummed, the rest of the sheet being ungummed. This is known as “strip gummed paper” and the process of gumming it is known as “strip gumming”. The present invention relates to the manufacture of pa10 per of this character.

It will be evident that the gummed margin of a strip gummed sheet of paper is thicker than the ungummed portion of the sheet. While this difference in thickness is 15 of no importance in an individual sheet, it does become a troublesome factor when the sheets are stacked, and it is particularly troublesome in printing strip gummed labels because the stack is necessarily higher on 20 one side than the other. This makes the stack unstable and it also interferes with the operation of certain types of sheet feeding mechanisms used in printing machines.

The present invention has for its chief ob25 ject to overcome this difficulty. In other words, the invention aims to devise a strip gummed paper and a process of making it Avhich Avill produce a sheet that is substantially level.

Tlie nature of the invention will be readily understood from the folloAving description Avhen read in connection Avith the accompanying drawings, and the novel features Avill be particularly pointed out in the 35 appended claims.

The single figure of the accompanying drawing is a diagrammatic view, in perspective, illustrating a process of strip coating paper embodying the present invention.

Referring to the draiving, 2 designates a supply roll of paper from Avhich a continuous strip S is drawn. This strip travels over a roll 3 having raised peripheral portions or rings 4 with which the paper is 45 held in contact by means of another roll 5.

Strips of gum are applied to the paper by the rings 4, this gum consisting of glue, dextrine, or any other suitable substance, and , the supply being held in a tank 6. A feed 50 roll 7 is partially submerged» in the liquid gum and transfers it to an intermediate roller 8, usually covered Avith felt, which, in turn, delivers the gum to the rings 4 of the strip roll 3, this arrangement ensuring the application of a limited and uniform quan- 65 tity of gum to the paper. The strips of gum so applied are indicated at G.

The paper next runs over a roll 9 which forces the paper in contact with another strip roll 10, similar to the roll 3, but cut 60 away at the parts which otherwise would engage the gummed surface of the paper. This roll also has raised annular portions 12 that run in contact with the ungummed sections of the paper and apply to these por- 65 tions a coating of a non-adhesive material, such for example, as a mixture of clay or kaolin with casein or starch. Practically any filler mixed Avith a suitable size or binder will answer for this purpose. This ⁷⁰mixture may also be. colored, if desired. The non-adhesive coating material is applied in liquid form, and for this purpose is mixed with water, the mixture being fed to the strip roll 10 in substantially the same ⁷⁵manner that the gum is fed to the strip roll

3. That is, the non-adhesive coating material is poured into a tank or trough 13 in which a feed roll 14 revolves, this roll transferring the material to a felt covered roll 15 ⁸⁰which, in turn, delivers it to the raised surfaces 12 of the strip roll 10.

From the latter roll the strip of paper travels over guide rolls 16 and 17. and is then wound up in a roll 18, suitable time ⁸⁴being allowed in the travel of the strip to enable the coating to dry. Or the strip may be run over one or more heated rolls to hasten the drying operation.

With the arrangement above described the ⁸⁰coating of non-adhesive material applied to the paper is substantially equal in thickness to the coating of gum. Where, due to the nature of the materials handled, a more accurate control is necessary than can be ob- ⁸⁶tained by the arrangement shoAvn, it may be necessary to use scrapers or “doctors” on the feed rolls, as will be readily understood by those skilled in this art.

It will be observed that a portion of the ¹⁰⁰paper is coated with gum and that the remaining ungummed surface is coated with an equal thickness of a non-adhesive material. The coated sheet, therefore, is of a substantially Uniform thickness throughout ¹⁰⁵its entire area. Consequently, when this sheet is cut up into smaller sheets of the proper size for labels, stickers, posters, or the like, and these pieces are stacked for j printing, the stack will be substantially level ,i at all heights because each individual sheet I in it is level. The difficulty which has been 5 encountered heretofore in printing a strip gummed paper is thus effectually overcome. As shown, the gum is applied to the paper in strips G and these strips are separated from each other by non-adhesive coating 10 strips C. It will be understood, however.

that the particular way in which the coatings are applied, the widths of the strips, and the like, will be determined by the use which is to be made of the paper. While, 15 therefore, I have herein shown and described a typical arrangement for practicing the present invention, it will be understood that the process provided by this invention may be practiced in other ways.