US 3419005 A
Description (OCR text may contain errors)
United States Patent 3,419,005 APPLICATOR TUBE Albert W. Lewing, Monson, Mass.; Third National Bank of Hampden County administrator with the will annexed of the estate of said Albert W. Lewing, deceased, assignor to Tampax Incorporated, a corporation of Delaware No Drawing. Filed Apr. 19, 1966, Ser. No. 543,508 12 Claims. (Cl. 128-263) ABSTRACT OF THE DISCLOSURE A paper catamenial tampon applicator tube having a surfactant wetting agent in an amount in the order of 0.1% to 1.2% by weight of the tube and distributed throughout the tube in the paper and/ or the glue of the tube. Through the use of an unexpectedly small addition of a wetting agent, the applicator tube is readily wettable to soften and delaminate into a condition effective to facilitate disposal in a toilet. The addition of mineral filler to bring the specific gravity of the tube above 1 enhances the effectiveness of this small amount of wetting agent.
This invention relates to applicators for catamenial tampons; and more especially to such tampon applicators which are adapted to readily sink and to disintegrate in water to an extent such that they will not obstruct plumbing if they are thrown into a toilet and flushed into the exit pipe.
The usual catamenial tampon is a compressed cotton cylinder contained in a paper tube and With a slightly smaller paper tube telescoped into the first for pushing out the tampon.
In order to be useful, such applicators are best made stiff, e.g., by winding successive layers of paper strip in crossed spirals with adhesive between the layers bonding them together; but, when they are discarded into waste pipes, this very stiffness is likely to result in jamming them across the pipes so as to block normal flow.
According to the present invention, delamination of such tubes is facilitated and accelerated by wetting agent (surfactant) in the adhesive or in the paper. This surfactant causes the water to penetrate quickly into or between the layers of paper, where it quickly softens the adhesive to the extent that the layers of paper drift apart, and softens the paper to facilitate such drifting apart and thus to allow the paper to fiow with the liquid through the waste pipes. Advantageously the paper is such as can disintegrate to free at least some of its fibers when thus Wet; and the surfactant, by encouraging the entry of water between the fibers, assures that such disintegration will occur as soon as possible.
The use of wetting agents in the adhesive and/or in the paper used for catamenial applicator tubes is not new per se. For more than fifteen years we have used sodium silicate as a wetting agent to facilitate disposal by accelerating softening and disintegration of the paper tubes. Polyvinyl alcohol and carboxymethyl cellulose, used in such applicator tubes many years ago, do have some wetting agent effect, but were used primarily to improve the adhesive as such. Ten years ago we began using cationic surfactants such as quaternary ammonium compounds, especially the higher alkyl (such as lauryl or cetyl, etc.) dimethylbenzyl (or trimethyl, etc.) ammonium chloride (or bromide, etc.) in catamenial tampon applicators.
Wetting agents have been used also in paper towels, handkerchiefs, and napkins to increase absorbency, but these products require papers of high wet strength which will not disintegrate when wet in ordinary use. See also references to Wetting agents in paper, Technology of 3,419,005 Patented Dec. 31, 1968 Coated and Processed Papers, by Mosher (1952) and Modern Pulp and Paper Making, by I. B. Calkins (1957), see particularly pp. 40 and 140.
I have now discovered that a very small addition of a surfactant is most effective to facilitate disposal by flushing down the toilet, and is, in general, better than a larger amount.
As an example of the practical application of the invention, laminated tube applicators are made as in the prior art by spirally winding strips of paper, first in one direction and then in a cross direction onto a mandrel. A film of water soluble adhesive is spread onto one or both faces of the paper which lie against one another; and when the adhesive is set the resulting tube is cut to desired lengths for the applicators.
The adhesive is advantageously a vegetable water-soluble base. By water-soluble I do not require that it form a molecular dispersion in water, but merely that the material so combine and disperse in water that a dry film loses its strength and its identity.
So long as the tube remains dry, it is a rigid structure, reinforced by the laminated fibers of the several layers and the interposed adhesive, but it can be delaminated by soaking in water, which soaks up into the adhesive layer, weakening it and dispersing it, so that it loses all strength; and this is facilitated by capillary action of the fibers.
Example I According to one embodiment of the present invention, a wetting agent such as Triton X (alkyl phenoxy ethoxy ethanol) is added to the pulp used for paper making in the proportion of one to 1,000 pounds of paper (i.e., 0.1%). The wetting agent is adsorbed on the cellulose fiber and is present in the paper in amount only a little less than that added.
Example II For example, when Roccal (a quaternary ammonium wetting agent) is added to paper pulp in the beater in proportion 16.7 parts by weight for 1,000 parts by Weight of paper, 12 parts (i.e. 1.2%) are effectively held adsorbed on the fiber so as to be carried by the final, dry paper.
Example III Instead of the Triton X100 of Example I, I have used Duponal (sodium lauryl sulfate) in the same way, but it sometimes causes difficulty in lifting the web off the wet rolls.
Instead of, or in addition to, the adding of surfactant to the paper pulp so that it is carried on the fiber, I have added it to the glue so that it facilitates entry of water into the dried glue film and also along the fibers which are in contact with the glue. Thus a laminated paper tube so treated will quickly delaminate and stream out when thrown into the toilet bowl.
I have also found it advantageous to dip the cut ends of the tube into a solution of the wetting agent, which thereupon creeps up along the fibers and leaves a minute coating of the surfactant to facilitate rewetting when the paper is latter exposed to water.
It is desirable that the paper products according to my invention should sink slowly in water, so that full exposure to the water is assured. To this end I may load the paper with a mineral filler, e.g., calcium carbonate, in amount sufficient to raise the specific gravity of the paper just a little above unity. The surfactant itself also serves this function by reducing the surface tension and promoting swift wetting which allows the paper to sink. This is particularly desirable in toilets which do not have siphon action.
1. A catamenial tampon applicator tube which comprises paper strips adhesively held together in said tube structure and which is characterized by surfactant wetting agent in an amount sufficient to at least readily watersoften said tube and also in an amount in the order of 0.1% to 1.2% of the weight of the tube and distributed substantially throughout.
2. A catamenial tampon applicator as defined in claim 1 in which at least a part of the surfactant is cationic.
3. An applicator as in claim 1 in which at least a part of the surfactant is a quaternary ammonium compound.
4. An applicator as in claim 1 in which at least a part of the surfactant is a Roccal.
5. An applicator as in claim 1 in which at least a part of the surfactant is an n-higher alkyl trialkyl (lower) ammonium halide.
6. An applicator as in claim 1 in which at least a part of the surfactant is sodium lauryl sulfate.
7. An applicator as in claim 1 in which at least a part of the surfactant is alkyl phenoxy ethoxy ethanol.
8. An applicator as in claim 1 in which at least a part of the surfactant is in the paper distributed on the fibers thereof.
9. An applicator as in claim 1 in which at least a part of the surfactant is in the glue between the strips of paper.
10. An applicator as in claim 1 in which at least a part of the surfactant is on the ends of the laminated tubes.
11. An applicator as in claim 1 wherein the specific gravity of said tube is above unity.
12. An applicator as in claim 1 wherein the paper of said tube has been loaded with mineral filler to raise the specific gravity of the tube.
References Cited UNITED STATES PATENTS 2,340,311 2/1944 Donovan 128285 2,712,315 7/1955 Rice l28261 ADELE M. EAGER, Primary Examiner.
US. Cl. X.R.