Title:
Method of making pressure sensitive labels
United States Patent 2391539


Abstract:
This invention relates to a method of making pressure sensitive adhesive tapes, labels, and the like, and the resulting product. An object of the invention Is to provide a backing sheet on which separated tapes or labels are mounted by means of a normally tacky adhesive commonly referred to...



Inventors:
Stanton, Avery Ray
Application Number:
US45077442A
Publication Date:
12/25/1945
Filing Date:
07/13/1942
Assignee:
Stanton, Avery Ray
Primary Class:
Other Classes:
40/638, 271/8.1
International Classes:
B31D1/02
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Description:

This invention relates to a method of making pressure sensitive adhesive tapes, labels, and the like, and the resulting product.

An object of the invention Is to provide a backing sheet on which separated tapes or labels are mounted by means of a normally tacky adhesive commonly referred to in this art as pressure sensitive adhesive, whereby the backing sheet may serve as a convenient holder for holding the tapes or labels conveniently assembled together prior to the removal of the tapes or labels upon their application to various articles that the tapes or labels are to be applied.

More specifically, an object of the invention is to provide a method whereby the paper stock that forms the tapes or labels is divided into separated portions prior to its being brought into adhesive engagement with the backing whereby the portions of the paper stock, although separated from each other are, nevertheless, in contiguous relationship covering substantially the entire backing so that the adhesive will be effectively protected thereby but enabling the separated portions to be individually removed.

Another object of the invention is to provide a method of making pressure sensitive tapes and labels wherein a backing is employed to which the adhesive does not strongly adhere and the adhesive is originally applied to the backing and the paper stock which has been first longitudinally divided is then brought into engagement with the adhesive on the backing so that, in effect, the adhesive is transferred from the backing to the paper and upon subsequent removal of the paper from the backing the adhesive will be removed from the backing along with the paper.

Another object of the invention is to provide a method of making pressure sensitive adhesive labels and the like, wherein the paper stock that forms the labels is first longitudinally divided and is then laminated with the backing with pressure sensitive adhesive between the paper and the backing and thereafter:the laminated material is divided upon transverse lines or upon lines that intersect the longitudinal division lines to divide the paper stock into the individual labels or stripg of the desired size and shape. Such transverse lines on which the paper stock is divided may extend also through the backing, enabling the resulting sheet of labels to be separated readily into transversely extending strips that can be conveniently handled. In some instances, It is desirable to have only the paper stock divided upon the transverse lines leaving the backing undivided on these lines to afford a stronger backing for holding the labels in assembled relationship.

Still a further object of the invention is to provide a method of manufacturing pressure sen6 sitive adhesive labels wherein the adhesive is applied to either the backing or to the paper stock in spaced longitudinally extending stripes and the paper stock is divided longitudinally upon lines intermediate the sides of the spaces between the stripes, thus affording free margins at the side:s or edges of the labels that can be readily graii.ed to facilitate peeling or removing the lab(-i. from the backing.

ithh the foregoing and other objects in view, which will be made manifest in the following detailed description and specifically pointed out in the appended claims, reference is had to the accompanying drawing for an illustrative embodiment of the invention, wherein: Figure 1 is a diagrammatic view illustrating apparatus that may be employed to perform the improved method and obtain the resulting product; 1Pg. 2 is a plan view of one form of product obtainable by the use of the improved method; Figs. 3, 4, and 5 are similar views illustrating other types of products that are obtainable from the use of the improved method; and Fig. 6 is a sectional view through a die that may be employed in the manufacture of the product illustrated in Fig. 5.

Referring to the accompanying drawing wherein similar reference characters designate similar parts throughout, 10 indicates a storage,of paper stock drawn from a suitable supply such as a supply roll of paper, not shown, and whichi is drawn between laminating rolls II and 12 over suitable guide rolls 13 and 14. This paper stock may be of any desired type that is to subsequently form the tapes or labels. 16 indicates a storage of backing that is trained over rolls 16, 1, 18e 19, .and 20 prior to being fed between the laminating rolls 1 and 12. 21 indicates a gumbox or a suitable reservoir for pressure sensitive adhesive 22.

It will be noted that the backing as it passes over the roll 19 is temporarily Immersed in the adhesive 22 so as to be coated therewith on its under side which becomes uppermost on the backing after it passes over the roll 20. A roller 23 is disposed in the gum box and serves to wipe off excess adhesive that may adhere to the backing. This roller may be plain so as to leave the backing uniformly coated with adhesive or it may have raised ridges circumferentially formed thereon at longitudinally spaced intervals which ridges will wipe off the adhesive entirely from the backing along spaced narrow stripes. In place of the wiping roller a wiping blade may be employed if desired.

The backing employed with the improved method is preferably one to which the adhesive does not have any strong affinity. A typical backing that is suitable is glassine although other backings, such as for example Cellophane or Plioflm, may be employed in certain instances.

24 indicates a gang of cutters having longitudinally extending cutting blades 25 suitably spaced from each other located immediately prior to the laminating roll I1. These cutting edges which are usually in the form of razor blades or the like longitudinally divide the paper stock 10 upon the spaced longitudinally extending division lines 26.

A feature of the invention resides in the fact that the paper 10 is longitudinally divided prior. to its being brought into adhesive engagement with the backing 15 that has the coating of adhesive thereon. With such an arrangement the cutting edges or blades 25 cut through the paper while it is still dry and while it has no adhesive applied thereto. If the cutting of the paper is deferred until after the adhesive is applied to the paper, then the adhesive tends to be picked up by the cutting blades with the result that the blades must be regularly and periodically cleaned unless cutting of the paper can be accomplished along stripes or areas to which no adhesive has been applied. With the arrangement as shown in Fig. 1, the apparatus can be centinuously operated without the cutting edges 15 becoming gummed and requiring periodic shutdowns and cleaning.

Although the paper is longitudinally divided by the cutting blades 25 into separated strips 27, these strips remain in contiguous edge-to-edge relationship and as the strips pass with the backing 15 between the laminating rolls II and 12 they are pressed into firm engagement with the adhesive on the backing effectively resulting in a transfer of the adhesive from the backing to the paper. Although the adhesive thus becomes firmly attached to the paper it still remains attached to the backing but on separating or peeling the paper from the backing it will be found that most, if not all, of the adhesive remains attached to the paper and separates itself from the backing.

After the laminated material passes from between the rolls II and 12 it may then be cut into suitable sections, such as by a die 28 producing an article, such as is illustrated in Fig. 2, consisting of the backing 15a with strips 21 temporarily adhering thereto by the pressure sensitive adhesive, these strips extending longitudinally of the backing. Frequently, it is desired to provide a suitable margin or binding portion 29 that may be punchedas at 30 to enable the sheets to be kept in a suitable binder for purposes of convenience. The strips 27 can then be readily removed individually from the backing and applied to any article desired. They may have 6 printed matter applied thereto. 6 When it is desired to have the strips 27 divided into smaller sections, such as individual labels 31, the sheet produced by the method and illustrated in Fig. 2 can thereafter be divided upon transverse lines 32 by running the sheets through a suitable die that will cut through both the paper stock and the backing. I find it convenient to divide the sheets in this manner by merely positioning them in a letter press which has transversely extending cutting rules mounted 76 therein that will divide the sheets upon these transverse lines. Such cutting rule preferably does not extend into the margin or binding portion 29 but if it does extend into the margin or binding portion 29, that portion that traverses the binding portion preferably does not cut but merely perforates the binding portion as indicated at 33 so that the marginal portion 29 remains largely, if not entirely, intact to hold the transversely extending strips of the backing in assembled relationship.' Similarly, as shown in Fig. 4, if desired the transverse cutting rules or dies may leave small fragile connecting webs 34 so that although the backing is largely divided into transversely extending strips they are nevertheless temporarily held together so that the sheet, although it is readily divisible, nevertheless is held together to facilitate its handling as a complete sheet.

The labels 31 in Figs. 3 and 4 can be readily peeled from the backing 15a or if desired the sheet may be divided or separated upon the transverse lines into individual strips each carrying a relatively small number of labels and from which the labels can be individually picked or peeled off.

In some instances it is highly desirable to divide the paper only upon the transverse lines, in which case a die such as is illustrated in Fig. 6, may be employed. In this form of construction it Is virtually essential that a hard, unyielding backing be employed of the character of glassine. Such a backing is relatively incompressible as compared with ordinary paper. By so regulating the cutting edge 35 it may be caused to penetrate the paper only without cutting through the backing.

If the backing is somewhat compressible or rubber-like as in the case of Cellophane, Pliofilm and like materials, this cutting of the paper without cutting the backing simultaneously therewith is virtually impossible in that the backing compresses under the cutting edge 35 and when the cutting edge penetrates the paper it has a tendency to snap through the backing also. By using an incompressible hard backing, such as glassine such snapping through does not take place with the result that the paper only is divided upon the transverse lines and the backing remains entirely intact, such as is illustrated in Fig. 5. In the die illustrated in Fig. 6, it is usually necessary to have the impression die come into metal-to-metal contact with the anvil or matrix towards which the die is forced.

Fig. 5 illustrates another form of product obtainable by use of the present method. In this form of construction the backing 15 has the adhesive 22 applied therete in longitudinally extending spaced stripes 36 spaced from each other by uncoated or desensitized stripes or areas 37.

These uncoated or desensitized areas may be formed by either having the roll 23 wipe adhesive therefrom entirely or an applying roll may be employed that picks up adhesive from the gum box and applies it only to the stripes 36 leaving the areas 37. In producing this form of construction it is possible to apply the adhesive in stripes to the under side of the paper stock 10 rather than to the upper side of the backing. The cutting blades 25 are then arranged to cut the paper stock on longitudinal lines 38 that are arranged intermediate the sides of the desensitized or urcoated areas 37, so that when the-paper and backing pass together through the laminating rolls II and 12 the paper and backing are laminated together but the areas 37 on each side of the division lines 88 provide free margins or portions at the edges of the labels that are detached from the backing to facilitate their being grasped and peeled from the backing. In manufacturing the article illustrated in Fig. 5, the longitudinal strips of paper may be left undivided as in Fig. 2, or they may be divided along with the backing as illustrated in Figs. 3 and 4, or the paper alone may be divided leaving the backing intact by subjecting the resulting sheet to a die as illustrated in Fig. 6.

From the above-described construction and method it will be appreciated that it is possible to produce sheets of tapes or labels contiguously arranged upon a backing and to longitudinally divide the paper stock prior to its coming in contact with the adhesive so that danger of the adhesive accumulating on the cutting knives 25 is entirely avoided. The resulting product may then be optionally transversely cut into individual labels by either cutting through the paper and backing entirely on transverse lines, or by leaving temporary connections, such as are afforded by the webs 34, or the paper stock alone may be divided upon transverse lines leaving the backing intact.

It is of course possible to divide the sheet of paper on the longitudinal lines as well as the transverse lines by using a die that is so regulated that it will penetrate the paper only provided that a hard, unyielding, and virtually incompressible backing such as glassine is employed. In so doing the backing and the paper are first laminated together and the die that cuts the longitudinal line 26 is arranged longitudinally. If the die is properly regulated it will cut the longitudinal lines without penetrating or snapping through the backing. This operation may be performed either before or after the sheet is subjected to the die 35 that cuts the transverse lines.

Various changes may be made in the details of construction without departing from the spirit or scope of the invention as defined by the appended claims.

I claim: 1. The method of manufacturing adhesive tapes, labels and the like comprising applying to a continuous backing a pressure sensitive adhesive, moving the backing and paper stock of substantially the same width as the backing width into laminating engagement with each other between laminating rolls so as to cause the adhesive to adhesively connect the backing and paper stock, and slitting the paper stock just prior to its passing through the laminating rolls into a plurality of strips which cooperate with each other to cover the adhesive on the backing.

2. The method of manufacturing adhesive tapes, labels and the like comprising applying to a continuous backing a pressure sensitive adhesive, moving the backing and paper stock of substantially the same width as the backing width into laminating engagement with each other between laminating rolls so as to cause the adhesive to adhesively connect the backing and paper stock, and slitting the paper stock just prior to its passing through the laminating rolls into a plurality of strips which cooperate with each other to cover the adhesive on the backing and thereafter transversely dividing the strips without dividing the backing.

as RAY STANTON AVERY.