GB2138431A - Polymeric blend and laminated films and related articles made therefrom, in particular human drainage containers or bogs for medical applications, having high noiselessness and pliability characteristics - Google Patents

Abstract

A polymer blend suitable for films having high noiselessness and pliability characteristics comprises 40% to 90% by weight of an olefinic polymer or copolymer, 10% to 60% by weight of a chlorinated polyolefine, and 3% to 10% by weight of chlorinated paraffines. Such films are suitable for the manufacture of human drainage containers or bags for medical applications.

Description

SPECIFICATION Polymeric blend and laminated films and related articles made therefrom in particular human drainage containers or bags for medical applications having high noiselessness and pliability characteristics This invention relates to the technical field of laminated films and related articles of manufacture, such as bags and containers.

More specifically, the invention concerns films having high noiselessness and pliability characteristics, which lend themselves specially well to the manufacture of containers and bags intended for human drainage in medical applications, and particularly for collecting excretion products from patients whose excretive apparatus has been reconstructed surgically.

Popularly, bags of this type are often called "ostomy" bags.

Easily imagined, and actually readily ascertainable, is the discomfort suffered by patients who, having undergone surgical intervention directed to reconstruct or deviate, albeit in part only, their excretive apparatus following traumatic or pathological events -- in particular of the tumoral type -- are then obliged to carry along a personal container of excretion products continuously during their active life.

In general, such patients find themselves with an artificial anus formed from a protruding intestinal portion whereto a collecting container is connected which is carried at the waist region close against the skin, under the patient's garments.

There exist a few features that a patient of the kind in question would heartily welcome of such a container, the presence of which container should desirably pass unnoticed by other persons met in the course of the patient's activities.

Currently available from a number of manufacturers are excretion product collecting containers which meet some of the requirements set forth by deviated excretion apparatus patients. These containers, which are formed generally from plastic film materials, exhibit features which could be regarded as reasonably satisfactory for the using patient. Among these features, mechanical properties may be mentioned which afford a good degree of protection against wear, abrasion, and puncturing, as well as gas and odor barrier properties.

However, and beyond the results achieved thus far, there still exists the need for "concealing from others" in a really effective fashion one's'condition of disability. It has been found, in fact, that the use of heretofore commercially available containers makes the patient feel uneasy about such containers emitting, specially as the patient moves around, noise of a low but still audible intensity level.

Furthermore, the containers employed in the past exhibit a texture and "feel" which make them less than ideally suited to applications involving compatibility with human skin so that the patient is never allowed to at least occasionally "forget" his/her disabled condition, with obvious disturbing consequences of a psychological nature.

It is an object of this invention, in order to correct such prior deficiencies, to provide a film which, additionally to desirable properties of resistance to wear abrasion and puncturing, and as a gas and odor barrier has improved quietness features characterized by a sound emission of so low an intensity as to be imperceptible to the human ear through most of the audible frequency range.

A further object of this invention is to provide a film as indicated which is so pliable and soft as to stand comparison with the characteristics of human skin itself.

Another object of the invention, consequent to the former, is to provide bags or containers intended in particular for human draining and collecting excretion products from patients having a deviated reconstructed excretive apparatus which exhibit high noiselessness and human skin compatibility features.

Accordingly a first aspect of the invention provides a polymeric blend, comprising 40% to 90% by weight of an olefinic polymer or copolymer, 10% to 60% by weight of a chlorinated polyolefine, and 3% to 10% by weight of chlorinated paraffines.

According to a second aspect of the invention, a film is formed from such a polymeric blend. The film may be a multilayer laminated film.

According to a further aspect of the invention, there are provided drainage containers or bags for medical applications, useful to collect excretion products from patients whose excretive apparatus has been reconstructed and/or deviated, characterized by high noiselessness and pliability properties, as well as by properties of resistance to wear, abrasion, and puncturing, and of gas and odor barrier, said bags or containers being formed from a laminated film which comprises at least one layer comprised of said polymeric blend.

This invention is based essentially on the finding that a film formed from a polymeric blend comprising 40% to 90% by weight of an olefinic polymer or copolymer, 10% to 60% by weight of a chlorinated polyolefine, and 3% to 10% by weight of chlorinated paraffins, is possessed of quite unusual properties of quietness and pliability.

In particular, if in the polymeric blend, as the olefinic polymer and copolymer, an ethylene-vinylacetate (EVA) copolymer is used with chlorinated polyethylene as the chlorinated polyolefine, then it is observed that the addition, in amounts ranging from 3% to 10% by weight, of chlorinated paraffin imparts to the resulting film a degree of quietness, in a rubbing and shuffling environment, and pliability and softness such that none of the films used heretoffore have been able to accomplish.

More specifically, it is observed that it is expedient for the ethylene-vinyl acetate (EVA) copolymer utilized to have a vinyl acetate content in the 14-22% by weight range, while as regards chlorinated polyethylene, it is preferable that the chlorine content ranges from 36% to 44% by weight, and that the polymer has a density in the 1.16 to 1.22 g/cm3 range. Alternatively, for the olefinic polymer or copolymer, either in lieu of or in addition to EVA, use may be made of low density polyethylene, copolymers of ethyleneacrylic acid and ethylene-ethyl acrylate, or ethylene-ethylacrylate, polybutadiene, polybutylene, and mixtures thereof.

The chlorinated paraffins which enter, in amounts ranging from 3% to 10% by weight, in the composition of the initial polymeric mixture are liquid at ambient temperature, having a viscodity at 20"C which ranges from 1 to 30 poises, preferably 10-15 poises, and a chlorine content of 40-60% by weight, e.g.

56% by weight.

The polymeric mixture or blend may be processed according to conventional practices, for example by an extruding process, and has the desirable characteristic of being easily workable as such; the addition of workability promoters, such as amidic waxes and sili- cones, may be useful with certain types of blends and somr processing operations. Such additives, provided to a modest amount of 02% by weight, can facilitate, among others, separation from the surfaces of the processing machinery during the manufacture of the film from the polymeric blend.

The polymeric blend, in turn, may be prepared with conventional methods. A preliminary compounding step preferably by means of a twin-screw extruder has been shown to be the best method of mixing together the olefinic polymer or copolymer and chlorinated poly-olefine.

In particular, a compounding step carried but on ethylene-vinyl acetate (in granules) and chlorinated polyethylene (in powder form) by means of a twin-screw extender with the addition of chlorinated paraffins, results in a polymeric blend which, once extruded into a fill, yields as a product a film which virtually emits no perceptable noise in a rubbing and shuffling environment, and has a feel or texture which is quite similar to that of human skin, namely pliable and soft.

A film prepared as described hereinabove, in addition to the cited quietness, pliability, and softness features, also has excellent properties of resistance to wear, abrasion, and punctuting, and lends itself for welding with pratically all of the methods conventionally employed for this purpose.

For special applications, the invention provides for the use of at least one layer comprising said polymeric blend joined or connected to other layers of varying characteristics thereby forming multilayer laminated films.

The characteristics of the additional layers will depend on the intended final use of the multilayer laminated film.

The junction of the layers which make up a multilayered film comprising at least one layer of polymeric blend, according to the invention, may be accomplished with traditional methods, such as irapped bubble co-extrusion and lamination with intervening adhesive layers. An advantageous aspect of the instant invention is that the polymeric blend processing into the final film requires no thermal stabilizers.

One example of such a multilayer film is represented by a film useful in the manufacture of bags or containers intended for draining and/or collecting excretion products from patents whose excretive apparatus has been reconstructed and/or deviated surgically following traumatic or pathological events.

In that case, the final film would be required to possess, in addition to those properties which are typical of the polymeric blend layer - i.e. quietness, pliability, softness, mechanical strength, and good weldability - also enhanced gas and odor barrier capabilities. A sample example of a multilayer laminated film having such characteristics is the following: Polymeric blend/Gas barrier/Polymeric blend A gas and odor barrier layer may comprise conventional materials, as normally suitable for the purpose, such as vinylidene chloride copolymers with a co-monomer selected from acrylic ester, acrylic acid, and vinyl chloride, or an ethylene-vinyl alcohol copolymer, or vinylidene fluoride-vinyl flouride copolymer, or polyamides, or mixtures thereof, to a thickness dimension in the 10 to 30 ,u range. The barrier films which are copolymers of vinylidene chloride are designated herein as "PVDC".

Such a multilayered film would be quite successful in the manufacture of bags and containers; the bags and containers are soft and pliable, produce no perceptible noise, are resistant to thermal and mechanical stresses, while welding of the film edges invariably meet the safety requirements imposed on them.

Such bags and containers, when placed in contact with skin, produce no unpleasant feelings: the patient experiences no inconvenience or embarassment, while the absence of noise and rustle effectively makes the presence of the container undetectable.

The example which follows, only purports to illustrate the invention and not to restrict its field of application, it merely serving the purpose of emphasizing the degree of effectiveness achieved thereby. EXAMPLE A comparative test has been conducted to ascertain the intensity of the sound emissions of some films subjected to rubbing: in particu lar, the sound emissions have been evaluated respectively from a conventional film, as commercially available and already used for manufacturing drainage containers, and from a film prepared in accordance with this invention.

The conventional film, indicated at C, was CRYOVACtD MF-27 film, a product from W.

R. Grace s Co. which comprises the following three layers: EVA/PVDC/EVA.

The film prepared in accordance with this invention, indicated at A-1, comprised three layers, namely: - two outer layers, having a thickness of 20 y each, which included a poylmeric blend having the following composition: 44.2% ethylene-vinylacetate (EVA) copolymer (having a vinylacetate content equal to 18%), 50% chlorinated polyethylene (having a chlorine content equal to 42% and density equal to 1.22 g/cm3), 5% chlorinated paraffines, and 0.5% amidic waxes and silicones; - a gas and odor barrier inner layer, having a thickness of 1 5 ju, which included vinylidene chloride-vinyl chloride (PVOC) copolymer.

The film A-l was prepared with a trapped bubble hot coextrusion process, without using thermal stabilizers.

The graph of Figure 1 shows the intensity in dBA of the sound emitted versus frequency, in the 0-10 kiloHertz range.

It will be apparent from the graph that the film according to the invention shows a marked superiority. The curve A-1, which sets forth the values of intensity of the sound emission from the film A-1, remains, throughout the frequency range (0-10 kH) investigated, below the curve C, which sets forth in plotted form the intensity values of the sound emission from the conventional film C.

In particular, given that most of the sounds below 20 dBA and especially in the range from about 5 to about 8 kiloHertz cannot be perceived by a human ear (reference: Noise Unlimited, Inc., Somerville, New jersey, USA), the film A-1 prepared in accordance with this invention shows excellent quietness properties characterized by the emission of sound below the audible threshold.

The pliability and softness properties of the film according to the invention have also been found to provide a particularly pleasant "feel", with a texture comparable to that of human skin.

The added features of resistance to wear, abrasion, and puncturing, as well as gas and odor barrier capabilities, qualify said inventive film for use in the manufacture of containers and bags for medical applications, especially for draining and collecting excretion products from stomized patents.

Claims (16)

1. A polymeric blend comprising 40% to 90% by weight of an olefinic polymer or copolymer, 10% to 60% by weight of a chlorinated polyolefine and 3% to 10% by weight of chlorinated paraffines.

2. A polymeric blend according to claim 1, wherein said olefinic polymer or copolymer is selected from copolymers of ethylene-vinyl acetate low density polyethylene copolymers of ethylene-acrylic acid, ethylene-ethyl acrylate, and ethylene-methylacrylate, poly-butadiene, polybutylene, and mixtures thereof.

3. A polymeric blend according to claim 2, wherein said olefinic polymer or copolymer comprises a copolymer of ethylene-vinyl acetate having a vinyl acetate content equal to 14 to 22% by weight.

4. A polymeric blend according to claim 1, 2 or 3 wherein said chlorinated polyolefine comprises chlorinated polyethylene having a chlorine content in the 36 to 44% by weight range, and a density of 1.16 to 1.22 g/cm3.

5. A polymeric blend according to any one of claims 1 to 4 wherein said chlorinated paraffines are liquid at ambient temperature, having a viscosity at 20"C ranging from 1 to 30 poises and a chlorine content by weight in the 40% to 60% range.

6. A polymeric blend according to any of claims 1 to 5, including machinability promoters selected from amidic waxes and silicones in a percentage of up to 2% by weight.

7. A film formed from a polymeric blend according to any one of claims 1 to 6.

8. A multilayer laminated film,comprising at least one layer formed from a film based on said polymeric blend according to any one of claims 1 to 6, said layer being effective to impart to said laminated film high noiselessness and pliability characteristics.

9. A multilayer laminated film according to claim 8 comprising at least two layers formed from said polymeric blend, said layers functioning as layers effective to impart high characteristics of noiselessness and pliability in combination with desirable properties of resistance to wear, abrasion, and puncturing, and gas and odor barrier capabilities'.

10. A multilayer laminated film according to either claim 8 or 9, further comprising a gas and odor barrier layer.

11. A multilayer laminated film according to claim 10, wherein said barrier layer is selected from a copolymer of vinylidene chloride with a comonomer selected from vinyl chloride, acrylic ester, acrylic acid, and ethylene-vinyl alcohol copolymer, a vinylidene fluoride-vinyl fluoride copolymer, polyamides, and mixtures thereof, said barrier layer having a thickness dimension in the 10 to 30y range.

12. A multilayer laminated film according to any one of claims 8 to 11, wherein at least a part of said multiple layers are joined together by co-extrusion.

1 3. A multilayer laminated film according to any one of claims 8 to 11, wherein at least a part of said multiple layers are connected together by means of intervening adhesives.

14. A polymeric blend according to claim 1 and substantially as hereinbefore described.

1 5. A film according to claim 7 or claim 8, and substantially as hereinbefore described.

16. A bag or container formed from a laminated film according to any one of claims 8 to 13 and 15.

1 7. A bag or container according to claim 16, intended in particular for use in draining and collecting excretion products from patients whose excretive apparatus has been reconstructed and/or deviated, characterized by properties of noiselessness and pliability, as well as of resistance to wear, abrasion, and puncturing, and as gas and odor barriers.