MXPA97002397A - Leaf material adhes - Google Patents

Abstract

The present invention relates to an adhesive sheet material characterized in that it comprises: a support or porous reinforcement with opposite sides, which is made of fibers that absorb less than 4% by weight of water and a pressure sensitive adhesive, insoluble in water , which is capable of absorbing no more than 10% by weight of water and such adhesive is discontinuously coated on one side of the support to provide areas of the pressure sensitive adhesive interspersed with uncoated support areas, the support areas which are not coated by the adhesive are between 20 and 70% of the support area, where the porosity of the support is sufficient to provide the adhesive laminar material with a Gurley value measured on a Gurley Model 4110 densitometer according to ASTM method d726 -58 from 0 to 15 seconds per 100 cm3 of ai

Description

ADHESIVE LEAF MATERIAL Field of the invention The invention relates to an adhesive sheet material, such as an adhesive sheet, which is suitable for use on wet surfaces, in particular on wet skin. The adhesive sheet material adheres effectively to the wet surface and expels moisture from the surface.

BACKGROUND OF THE INVENTION Adhesive sheet materials for use in general industry, packaging and medicine / surgery are well known and highly developed. These materials are composed of a reinforcement and a coating of pressure sensitive adhesive (PSA), which are selected to provide an appropriate balance of the desirable properties for the adhesive sheet materials: adhesion and elasticity. In addition, such properties as peel strength and resistance to elastic deformation are frequently considered. These properties of the adhesive materials have been reviewed by Dahlquist in Interdisciplinarv Science Review. 2, 2 (1977) and more recently in Adhesives Age. March, 1982. Commonly, adhesive sheet materials or tapes are designed with selected variations of the above properties, such that the sheet or tape will effectively adhere to the finished surface. For example, a sheet or tape to adhere packaging will exhibit high REF: 24377 cohesion and adhesion, but low stretch capacity and elasticity. The peel strength for such packing tape will be low, but the resistance to cutting and plastic deformation will be high. A paper adhesion tape will generally exhibit high adhesion, but practically no elasticity. It will have a relatively high cut resistance. Its adhesion will be so high that the low pressure will cause it to adhere. A sheet or ribbon for use on living skin will exhibit moderate adhesion and moderate to high stretch and elasticity. The resistance to the cohesion of such sheet or tape must be high enough that no PSA residue will remain on the skin when the tape is removed. This sheet or tape will also exhibit a high adhesion, so that moderate pressure will cause the adhesion. The presence of a fluid between the sheet or tape and the surface to which it adheres will normally cause adhesion failures. Water and other non-adherent substances such as oil are well-known impediments for anyone trying to apply the tape to the skin. The physical barrier presented by the fluid prevents the PSA from adhering to the surface. Since such surfaces covered by the fluid are a perennial problem when using sheets and adhesive tapes, much research has been devoted to the solution. "Breathable" and "absorbent" adhesive tapes to combat this problem are commercially available and have been extensively described in the patent literature. For example, Copeland in US Patent No. 3,121,021 discloses a breathable surgical tape, made of a nonwoven reinforcement and a microporous layer of PSA. The microporous layer of PSA allows water vapor to pass through it. A different technique is described by Gander in U.S. Patent No. 3,579,628. Gander describes a coating film in which the film reinforcement absorbs water vapor and the water acts as a plasticizer for the polymer that makes up the film. The film is self-adhesive when wet. The water absorption of the film is also treated by Potter in the European patent application 0 091 800. Potter describes an adhesive surgical film in which the PSA is coated in a configuration on the film. The percula is water vapor absorbent. Rawlings has further developed the concept of absorbent deposit in U.S. Patent 5,010,883. Rawlings describes a sheet material coated with multilayer adhesive, in which the layer coated with adhesive is perforated for the transmission of water in the liquid state. The surface layer is a continuous vapor transmitting film. The liquid water is transported to a deposit region between the two layers and slowly evaporates as a vapor from the surface layer. These improvements in sheet materials or adhesive tapes, however, are designed to handle light amounts of moisture. They can not handle significant amounts of water in a liquid state. In addition, the absorbent capabilities of the PSAs and reinforcements normally used for such "absorbent" sheets and tapes limit the amount of moisture vapor that can be removed from the surface. Finally, the adhesive capacity of such sheets and tapes is poor when applied to wet surfaces. Consequently, at present, no sheet material or adhesive tape is available for use on extremely wet surfaces. In particular, no known sheet material or adhesive tape can be used effectively under water or on a surface such as the skin that has been wetted in a water stream. As a result, there is a need to develop a sheet material or adhesive tape, which is suitable for use even under extremely wet conditions. In addition, there is a need for the development of such sheet or tape material that will adhere to an extremely wet surface, such as skin covered with water or submerged in water.

Brief description of the invention The present invention is directed to a sheet material or adhesive tape which is suitable for use in adhesion to a wet or damp surface. The adhesive sheet material is made of a porous reinforcement having opposite sides and a pressure sensitive adhesive (PSA) coated on one side of the reinforcement. The PSA coating is discontinuous to provide interspersed PSA areas with untreated reinforcement areas. The reinforcement is a knitted or woven or non-woven construction of fibers that are substantially non-water absorbing. The non-absorbent nature of the fibers is a function of the composition of the fiber. The fibers useful in the present invention have a capacity to absorb no more than about 4 weight percent water; preferably not more than about 3 weight percent water. Due to this character, the water can pass unimpeded through the reinforcement. Eil PSA is insoluble in water and relatively non-absorbent. The amount of PSA coated per unit area of the whole reinforcement (i.e., coated and uncoated areas) is moderate to coarse, at least about 2 mg per square centimeter, preferably about 6 to about 15 mg per square centimeter. This amount allows the adhesive sheet material to adhere well to the surface when the sheet material is used. Preferably, the PSA also has an adhesion and elasticity balance to allow it to adhere to the living skin. Alternatively, these PSA properties can also be adjusted to the particular needs of inanimate surfaces. The configuration of the PSA coating on the reinforcement allows efficient movement of the surface water to and through the reinforcement when the adhesive sheet material is used. The distance from the middle part of a PSA area to a non-adhesive reinforcement area is calculated to allow the movement of water from the PSA to the reinforcement without adhesive in a matter of seconds. The size of the individual areas of the PSA coating on the adhesive sheet material is not more than 5 mm in at least one dimension, preferably from about 0.5 mm to about 5 mm, more preferably about 1 to about 3 mm and more preferably not greater than 5 mm in any of the two dimensions. The total area of the PSA is from about 30 percent to about 80 percent of the total area of the sheet material, preferably from about 40 to 70 percent. Consequently, the area of the reinforcement, which is not covered by the adhesive is between about 20 and 70 percent of the reinforcement area. The PSA coating configuration may consist of point configurations, band configurations, wave configurations, lines, squares and other regular or irregular configurations. The invention is also directed to a method for adhering an adhesive sheet material to a wet surface with an aqueous fluid such as water. The method includes the step of applying to the wet surface an adhesive sheet material which will expel water from the surface and through the sheet reinforcement. By facilitating the movement of unobstructed water through the reinforcement and the short distance between the areas of the PSA coating and the uncoated reinforcement, the water on the surface is pressed to the external surface of the reinforcement during the application of the material of adhesive sheet. Therefore, the adhesive sheet material can adhere to a surface that is either wet with water or submerged in water.

DETAILED DESCRIPTION OF THE INVENTION The adhesive sheet material of the present invention shows strong, significant adhesion to surfaces that are completely wet or covered with water, "such as by a water film., running water or under water. The adhesive sheet material adheres to surfaces which will continue to be submerged in water, such as by flowing water or a body of water, or which will continue to develop significant amounts of water on their surfaces, for example, by sweating. The adhesive sheet material of the invention will adhere to dry surfaces as well. While not intended to be a limitation of the invention, it is believed that these wet adhesion characteristics are achieved by such properties of the adhesive sheet material as the discontinuous configuration of the PSA on the reinforcement, the water insoluble and non-absorbent nature of the PSA. PSA, the amount of the PSA present, the substantially non-water absorbing character of the reinforcement and preferably the porosity of the entire adhesive sheet material. It is believed that these properties direct the surface water to, and through the reinforcement when the adhesive sheet material is pressed onto a wet surface. It is believed that the discontinuous configuration and the water insoluble and non-absorbent nature of the PSA cause the displacement of surface water that is contacted by PSA. The application pressure drives the water to, and through the reinforcement. It is believed that the substantially non-water absorbing character of the reinforcement facilitates the passage of water to the external surface of the sheet material during the pumping action of water caused by the pressure of the adhesive sheet material on the surface during application. It is believed that the water insoluble and non-absorbent character and the amount of PSA seal the surface with which it is contacted, so that the water can not re-wet the surface.

The reinforcement and its fibers The reinforcement for the adhesive sheet material is formed of fibers and has a ns woven, reticulated or woven construction. The fibers are substantially non-absorbent of water, so that they absorb less than about 4 percent by weight of water, preferably less than 3 percent by weight of water. Functionally, this property means that the water is not absorbed into, or otherwise will be retained by the fibers. The fibers can be surface treated with a variety of agents (either hydrophobic or hydrophilic) as long as the agents do not revert to the water absorbing fibers. These properties allow the water to move unimpeded through the reinforcement and minimize the absorption or retention of water by reinforcement. The fiber structures useful in the present invention include a multilayer configuration, a coated configuration and a solid homogeneous configuration. These fibers are generally known in the art and are described in the Textile Encyclopedia, Third Edition, "The Manmade Fibers," pages 1-69, by the editors of American Fabrics and Fashions Magazine, Pientice-Hall, Inc., Englewood Cliffs, NJ; 1980, particularly pages 66-6!?. The multilayer fibers preferably have cores or centers composed of one or more polymers selected from a polyolefin, a polyester, a polyamide or a polyurethane and substituted forms thereof, wherein the substituents are pendent aprotic groups, such as alkyl groups ( preferably from 1 to 6 carbon atoms, aryl (preferably from 6 to atoms of; carbon), ester and halogen (hereinafter in the present "List of Polymers"). The outer layers of the multilayer fibers are also composed of one or more polymers in the list of polymers and may contain one or more hydrophobic or polymerized hydrophobic agents, such as fluorinated chemicals or appropriate silicones. The coated fibers are composed of centers or cores and coatings. The cores or centers are preferably composed of one or more polymers from the list of polymers. The coatings are embedded or bonded films covalently bonded to one or more hydrophobic agents for the fibers, such as silicones, fluorinated chemicals and other water repellent agents (e.g., water repellent and carpet repellent agents) and fabrics. ). Solid homogeneous fibers can be composed of one or more polymers from the list of polymers. The multilayer fibers, the coated fibers and the homogeneous solid fibers can be prepared by solution or emulsion spinning, extrusion and other techniques known in the art for the preparation of the fibers. See, for example, "Elements of Textiles" Jules Labarthe, Macmillan Publishing Co., Inc., New York, NY, 1975, chapters 4 and 6. Post-forming techniques, such as reactive or mechanical / thermal coating or polymerization of the surface layer can be used to form the multilayer or the coated fibers. Solid homogeneous fibers can constitute the cores for multilayer and coated fibers. The fibers are formed in the reinforcement by using known knitting, cross-linking or nonwoven techniques. See, for example, "Fabric Constructions" in "Elements of Textiles", Jules Labarthe, MacMillan, (1975) Chapter 6. The cross-linking or weaving of fibers, filaments of fibers or yarns composed of fibers, is effective for producing a reticulated reinforcement or fabric having fibers running in the longitudinal and lateral directions. The mechanical looms and the cross-linking supports or fabrics can be used to produce such cross-linked or woven material. The non-woven reinforcement may be produced by melt formation, for example, blown by melt spinning or blowing, air formation, mechanical formation with adhesion by a chemical, thermal or mechanical or hydro-entanglement process. These techniques are known and described in "Elements of Textiles", cited suora. The fibers are arranged to run in a longitudinal direction and a lateral direction.

The Pressure Sensitive Adhesive The pressure sensitive adhesive (PSA) used according to the invention is composed of a water-insoluble, nonabsorbent, preferably polymeric, viscoelastic polymer composition. The PSA is also tolerant to water, that is, it continues its function as an adhesive even in the presence of large amounts of water. The PSA also exhibits an adhesion, (as it is killed by the peel strength), a lift (ie, extension to which the adhesive prematurely separates from the surface to which the tape is applied) and a resistance to deformation elastic (that is, resistance to flow), which are appropriate for the particular surface under consideration. In general, the selection of the amounts and kinds of ingredients to provide the proper peel and lift resistance will depend on the nature of the finished surface. and the adherence that is going to be carried out. A resistance to moderate detachment and a low lift are preferred for use with live skin. A high resistance to detachment and a low lift are preferred for use with an inanimate object. For an explanation related to the peel strength and the lifting of the classes and amounts of PSA ingredients, see Kirk Othmer's Chemical Technology Encyclopedia, Fourth Edition, New York, NY 1992, Vol. 1, "Adhesives". The ingredients present in the PSA include a viscoelastic polymer and an optional adhesive. Fills, antioxidants, stabilizers and crosslinking agents can also be added. The viscoelastic polymer can have adhesion by itself, in which case no adhering ingredient is needed The viscoelastic polymer can be a polyacrylate, a polyolefin, a polyether, a polyisoprene, a butyl rubber, a natural rubber, a styrene-butadiene rubber , a polyurethane, a polyester and the like. The viscoelastic polymer can consist of mixtures or combinations of these polymers. Adhesion ingredients are known in the art and include, for example, resins, gums, dextrins and the like. Although the composition for the PSA (pressure sensitive adhesive) may include a combination of hydrophobic and hydrophilic ingredients, its overall characteristic must be non-absorbent, insoluble in water and water tolerant, "Non-absorbent" means that the PSA is capable of absorbing no more than about 10 weight percent water; preferably not more than about 7 weight percent water. "Insoluble in water" means that the PSA has a solubility in water of not more than 2 weight percent; preferably not more than 0 5 weight percent, The water-tolerant characteristic means that the PSA does not dissolve, degrade or disperse in water and its adhesive nature is not adversely affected by water.

Methods for forming the adhesive material PSA is applied to the reinforcement as geometric shapes to form the adhesive sheet material according to techniques known in the art. Such techniques include application by spraying, roller printing or machine printing, screen printing and similar simple contact techniques. For machine printing, a calendering apparatus containing the desired configuration or geometric shapes engraved on a cylinder, can be laminated first by means of the PSA or a solution of it and then laminate on the reinforcement. The calender has a surface composed of a release agent such as silicone, a polyperfluoro-olefin or other non-stick material such that the PSA will be released from the calender and will coat the reinforcement. The depressions on the row of calendering cylinders are filled with the PSA solution and cover a configuration of PSA geometric figures on the reflux. Block printing techniques, stencil printing and plate printing can be applied as the machine printing technique to directly produce the adhesive sheet material. A preferred method of application involves the PSA stenciling configuration on a release paper and the contact or lamination of the coated release paper to the reinforcement. The release paper process can be carried out in continuous or batch techniques. The continuous technique can use printing with stencil, spray printing or other coating methods for applying a PSA configuration on a mobile sheet of the release paper, followed by lamination of the release paper and the crosslinked, woven or non-woven reinforcement. The batch technique involves the printing in blocks or plates on such release paper and subsequent lamination of the reinforcement. Such release paper techniques are known in the art.

If the PSA consists of a curable composition, the pre-adhesive composition can be coated in a geometric shape configuration on the reinforcement by spraying, calendering, stencil printing and the like. Curing can be achieved by ultraviolet light radiation or by addition of a free radical curing agent to the pre-adhesive coated composition. In another technique, the PSA can be coated with solution in configurations as described above.

Physical characteristics of the adhesive sheet material The linear dimensions of the adhesive sheet material may incorporate designs to provide any desired shape and size of the adhesive sheet material. The dimensions can provide a self-rolling or jacketed roller, tape or any of the following on an internal release liner a sheet, a patch, a plug, a pad, a label, a rope, a line, a design of desired configuration, sheets or rectangular sheets that can be cut to any size and shape and any adhesive material or similar derived material. The thickness of the sheet material is limited only by practical concerns such as the volume and the ability of the sheet material to be dried. The adhesive sheet material of the present invention is porous due to its composition, its cross-linked, woven or non-woven character. and the coating in geometric shapes of the adhesive. The porosity of the entire adhesive sheet material is such that its Gurley value is preferably in the range of 0 to 15 seconds per 100 cc of air; preferably especially less than 2 seconds per 100 cc of air as measured on a Gurley Model 41 Densimeter 10 according to Method A of ASTM D726-56. The physical characteristics of the adhesive sheet material of the invention include flexibility and high conformability to the irregular surfaces. The property of resistance to detachment (adhesion measurement) of the adhesive sheet material can be varied according to the parameters desired for the specific application. The proper use of reinforcement strength combinations, tightness of the crosslinking, weaving or warp in the reinforcement and the appropriate adhesive character for the PSA can be selected by known techniques to obtain the desired variation in this property. For example, for adhesion to the skin. , an adhesive sheet material, will have a peel strength of at least about 0 1 Newtons per cm in width (25 grams per inch in width).

Modalities In one embodiment of the present invention, an adhesive sheet material can be prepared from a non-woven tape, adhered by the side of solid polypropylene fibers. This reinforcement can be prepared according to methods well known to those well skilled in the art (see, for example, "Elements of Textiles" (supra)). The reinforcement has a thickness of approximately 0 2 to 2 mm. The coating for this embodiment consists of a PSA composed of a viscoelastic polyacrylate, self-adhering, for example, as described by Ulrich in the reissue of US patent 24,906. The polyacrylate PSA is coated on the reinforcement in an amount of at least about 2 mg per square centimeter, preferably about 6 to 15 mg per square centimeter of the reinforcement and as points or circles having a radius of no more than about 1 mm, with no more than 5 mm (preferably not more than 1 mm) ) of the reinforcement without coating between the points. To prepare this embodiment of the adhesive sheet material, the PSA can be coated on a metal plate containing a negative embossed pattern of points, of dimensions mentioned above. The PSA in this configuration can be transferred to a silicone release paper and the release paper can be applied by lamination to the nonwoven reinforcement to form the adhesive sheet material. Figures preferred modalities are elaborated from reinforcements of non-woven ribbons, composed of rayon, polyester, polyamide, or polyolefin fibers or combinations of these fibers, which are coated with a non-water absorbing agent, such as a coating agent of a water-repellent, fluorinated chemical, a fluorinated polymer or a polysilicone. The non-water-absorbing agent can be bonded or embedded in the surface layer of the melt-niladed fibers or can be applied to the surface to any of the non-woven ribbons. See, for example, the description of US Pat. No. 5,027,803. reinforcements can be covered in geometric figures with a non-absorbent, water-soluble PSA, such as a polyacrylate ester, a viscous polyolefin with adherent or similar PSA. The PSA geometric pattern coating for these modalities can be constructed of PSA strips about 0 1 to 1 mm wide with spaces of 0 1 to 1 mm between and, approximately 6 to 15 mg of PSA per square cm of reinforcement Applications The tapes and adhesive sheet materials of the present invention can be used for medical and non-medical and industrial uses. These uses are especially desirable, wherein the surfaces to be covered or adhered are in extremely humid environments. It is generally found that a material The tape of the present invention will adhere strongly to a wet surface after a few seconds of pressure by the fingers to cause the PSA to eject water from the surface. In general, the resistance to the initial release of the sheet or tape will be of at least 0 1 newtons / cm wide, preferably from 0 15 to 0 20 Newtons / cm wide The following examples provide additional illustrations of the invention. However, these examples are not intended to be limitations of the invention, which is fully described by the above general text Example 1 Preparation and comparison of a PSA tape in configuration dots A PSA ribbon with dotted geometric figures is prepared by printing a sticky synthetic block copolymer of pressure sensitive adhesive of butadiene and styrene onto a non-woven rayon / polyester backing. The parameters of the tape are as follows. & The reinforcement consisted of a commercially available hydroentangled rayon / polyester non-woven reinforcement "HEF 703-2" (available from International Paper, Veratec Nonwovens Group, Walpole, MA) having the following specifications: i reinforcement width of 20 cm (8 inches); ii. reinforcement thickness of approximately 0.1 to 0.2 mm; iii. porosity of the reinforcement of 0 1 seconds per 100 cc of air (Gurley value); and iv a water absorbency of less than about 2 weight percent. b. The PSA was an adhesive prepared by mixing at 300 ° F (149 ° C) of a mixture consisting of 25 parts of "Kraton ™ 1112 Rubbers" (a rubbery or rubberized block copolymer of butadiene and styrene available from Shell Chemical Compapy , Houston, TX), 55 parts of "Wingtack Plus ™ Hydrocarbon Resins" (one hydrocarbon resin adhesive, available from Goodyear Tire and Chemical Corp., Akron, OH) and 20 parts of "Tufflo ™ Process Oil 3056 Mineral Oil" (available from Lyondell Petrochemical Co.,, Houston, TX) having a Tg (vitreous transition temperature) of 260 5 ° K (Kelvm) Printing was carried out by a conventional rotary screen printing technique. The parameters for printing included. at an adhesive application temperature of 150-155 ° C, b a 20 mesh screen for rotary printing, to provide a configuration of 20 mesh PSA points; c a print speed of 15-16 meters per minute; and d. an application of 7 95 to 8.37 mg of PSA per square centimeter of reinforcement. The PSA tape in dot configuration was evaluated dry and on the skin of the backs of six human volunteers, who had been wet with dripping paper towels. The available "Micropore ™ brand surgical tape" (3M) was also evaluated for a side-by-side comparison. The results of these evaluations are shown below and are reported as average.

Table 1 T-01 T-242 Survey3 Residue4 T-0-Humid5 PSA tape with "0 853 0 768 2 4 1 1 0.205 Points Configuration? N Micropore TM 0.127 0.533 2.0 0.0 0.062 1 The T-0 is the adhesion of the dry tape to a dry surface at time zero (after application) as measured according to the following protocol of adhesion to the skin. Adhesion was measured in force per unit width as Newtons per centimeter. 2 T-24 is the adhesion of the dry tape to a dry surface at 24 hours, as measured according to the following protocol of adhesion to the skin. The adhesion is calculated in force per unit width as Newtons per centimeter. 3 The survey is measured according to the following protocol. 4 The residue is measured according to the following protocol. 5 1 -0 is the adhesion of the tape to a wet surface at time zero, as measured according to the following protocol of adhesion to the skin. The units are Newtons per centimeter. The data demonstrated that the combination of the printed batch coating, hydrophobic PSA and non-wettable reinforcement gave a wet skin usefully high adhesion.

Protocols Adhesion to the skin The evaluation of the adhesiveness of a composition to human skin is an inherently subjective determination. Human skin has wide variations in composition, topography and the presence / absence of various body fluids. However, the average comparative values of adhesion are achievable when using test results from tapes of several individuals as described herein. Adhesion to the initial skin (T0), adhesion to the skin after 24 hours of continuous contact with the skin (T24) and adhesion to wet skin (TWET) are measured according to the adhesion test to the PSTC- 1 Widely accepted, for a single coated adhesive tape carried out at a 180 ° separation angle The PSTC-1 adhesion test is a test protocol established by the "Specifications and Technical Committee" of the "Pressure Sensitive Tape Council" with address at 5700 Old Orchard Road, Skokie, IL. The test was modified for the purposes of the present invention, by applying the tape to the skin of a living human being. Three samples measuring 2.5 cm wide by 7 6 cm long were applied to the back of each of the six human subjects (three men and three women). The subjects were placed in a prone position with the arms at their sides and the heads turned aside. The samples were applied on both sides of the spinal column with the length of each sample positioned at a right angle to the spinal column. applied without tension or traction of the skin. Those samples tested for adhesion to wet skin were impregnated into the skin, which had been moistened with a water-saturated cloth, leaving visible observable drops of standing water, immediately before sample application, samples they were pressed in place with a 2 Kg roller that is moved at a speed of approximately 2.5 cm / second with a single forward and reverse step. Do not apply manual pressure to the roller during application.

Then, the samples were removed either immediately after application (T0) or after 24 hours of continuous contact with the skin (T24), at a separation angle of 180 ° and separation speed of 15 cm per minute, uses a conventional adhesion testing apparatus, equipped with a 11.3 kg (25 lb) test line attached to a 2.5 cm clamp or clamp The clamp or clamp was attached to the edge of the furthest sample of the spinal column when lifting manually approximately 1 cm from the skin sample and join the clamp to the raised edge The adhesion tester is a tension meter mounted on a support or cart driven by motor. by force, required to effect the separation is reported in Newtons by centimeters. To adhere to moist skin, the wet T-0-value should be greater than about 0 1 Newtons / cm, Thus, the results of Table 1 indicate that the tape of the present invention will adhere to wet skin, in so much so that the standard "Micropore ™ Tape" does not.

Removal of the adhesive The evaluation of the adhesiveness of the adhesive of a composition to human skin is an inherently subjective determination, for the same reasons mentioned above, in relation to the evaluation of the adhesiveness of a composition to the composition of human skin.

However, the observational values regarding adhesive tenacity (lifting) are generally reproducible and in accordance with subjective determinations of similar properties.

Proof of adhesive removal is a subjective determination of the extent to which the adhesive tape is prematurely separated from the body, after application of a sample according to the skin adhesion test. The applied samples are visually inspected just before skin adhesion tests (ie, twenty-four hours after application) to determine the extent to which the edges of the sample have separated from the skin. A numerical classification from 0 to 5 is assigned to each sample based on the following observation: Classification Definition 0 No visible separation 1 Separation at the edges of the tape only 2 Separation from 1 to 25% of the area of the tape. 3 Separation from 26% to 50c of the area of the tape. 4 Separation from 51% to 75% of the tape area.

Separation from 76% to 100% of the area of the tape.

Each sample was assigned a single total number from the list previously established by each panel element. The assigned values of the panel elements (usually 6 elements) are then averaged and reported to the tenths position. Due to the subjective nature of the test, differences of less than 0 5 in averaged residual values should be considered substantially the same. Table I indicates that the tapes of the present invention have a lift substantially equivalent to standard tapes for use on human skin.

Residue dß adhesive Regarding the classification of the adhesive lift, a determination of the classification of the adhesive residue (Residue) of a composition to human skin, is an inherently subjective but reproducible determination The residue test of the adhesive is a subjective determination of the amount of adhesive remaining on the skin after separation of an adhesive sample according to the skin adhesion test. The skin directly underlying each sample was visually inspected to determine the extent to which the area contacted by the adhesive retained residual adhesive. Then, a numerical rating of 0 to 5 was assigned to each sample, based on the following observation.

Classification Definition 0 No visible residue 1 Residue on the edges of the tape only 2 Waste that covers 1% to 25% of the area tested. 3 Waste that covers 26% to 50% of the area tested. 4 Waste that covers 51% to 75% of the area tested. 5 Waste that covers 76% to 100% of the area tested.

Each sample was assigned a single integer from the list previously established by each panel element. Then, the assigned values of the panel elements (usually 6 elements) were averaged and reported to the tens position. Due to the subjective nature of the test, differences of less than 0.5 in average residue values should be considered substantially the same. Preferred skin adhesives will generally exhibit an average residue rating of less than about 2.5.

Example 2 PSA tape in dot configuration with fiber reinforcement coated with fluorinated chemical reinforcement Strip patterned, rayon tapes were prepared by rotary screen printing using the adhesive, apparatus and method in Example 1. The reinforcement used consisted of of a hydroentangled ribbon of rayon and polyester fibers of the type described in Example 1. The reinforcement had a width of 15 cm, a thickness of about 0.1 to 0.2 mm and a porosity of 0.1 seconds per 100 cc of air (value Gurley). (This reinforcement is indicated as "703-1" in Table II). In yet another variation, the reinforcement described above, was coated to saturation with 1.6 weight percent of an FC-270 mixture of fluorinated aliphatic chemicals (commercially available from the Company 3M, St. Paul, MN), followed by drying to the environment. (This reinforcement coated with the fluorinated chemical compound is indicated as "703-1 CF" in the Table II) In another variation, a reinforcement as above was prepared with 1% of a surface coating of the fluorinated chemical compound "FM 3559" from Company 3M. A tape was prepared from this reinforcement according to the procedure, parameters and PSA given above. (The uncoated reinforcement and the reinforcement coated with the fluorinated chemical compound are indicated as "703-2" and "703-2, FC" respectively, in Table II). Ribbons coated in geometric figures of the present invention are prepared, by using the various reinforcements not coated and coated with fluorinated chemical compound, described above, according to the procedures described in Example 1 The adhesive consisted of the copolymer described in Example 1, coated at 9.2 mg per square centimeter of reinforcement The following table provides the results of the tests carried out according to the procedures given in Example 1, for the tapes described above and the "Micropore ™ Tape". of 3M. 23 Table II T-G-dry reinforcement T-24-dry T-0-humid * 703-1 0.63 0.80 0.28 703-1. FC 0 64 0.90 0 28 703-2 0.76 0.85 0.24 703-2, FC 0 74 0.88 0 23 Micropore GM of 3M 0.15 0.46 0.05"Expressed in Newtons / cm Example 3 Ribbons printed on a plate Pressure sensitive adhesive tapes coated in geometric figures were prepared by using several different reinforcements, by a plate printing process. The plate consisted of a metal tool with raised ridges (0.2-0.25 mm high, 0.25 mm wide) in a square grid configuration that has a center-to-center distance from the grid squares of d 2.5 mm. The plate was coated with an illicone release agent ("Syloff 23" available from Dow Corning Corp., Midland, MI), mixed with 7.5% "Syloff 23A Catalyst 176" (a catalyst available from Dow Corning Corp, Midland, MI) The silicone / catalyst mixture was diluted to 6% solids with 50/50 peptane / heptane, painted on the printing plate and cured at 150X for 10 to 15 minutes. The coated plate was post-cured at approximately 25 ° C for several hours as described in the instructions for preparing the release agent, then the adhesive was coated on the plate and dried at approximately 25 ° C. The adhesive consisted of 70% by weight of isooctylacrylate, 15% by weight. acrylic acid weight and 15% in d) weight an acrylated polyethylene oxide oligomer, commercially available as "Carbowax 750" from Union Carbide Corp., present as 50 weight percent in a solvent of 60% ethyl acetate, 30% isopropyl alcohol and 10% toluene The strips of several non-woven ribbons were pressed on the surface and the adhesive was worked with a stiff bristle brush. The nonwoven tape reinforcements used were: (a) CFX nylon (available from Allied Signal Corp., East Privdence, Rl), (o) polypropylene melt blown ribbon, coated with octyl phenoxypolyethoxyethanol brand "Triton X-100" at 5% by weight (available from Union Carbide Chemical and Plastics Co., Danbury CT), and (o) a polyethylene-coated spunbond tape with 1% Atmer 385 surfactant (available from ICI Americas, Wilmington, FROM). The strips of the duct-coated adhesive tape were separated from the board and applied to the palm of a wet hand by holding it in place with pressure for 5 to 10 seconds. After 1 to 2 minutes all the plants showed resistance to be separated Comparative Example 4 A commercially available pressure-sensitive adhesive tape, coated on geometric figures, was evaluated as described in Example 1 except that the tape was used on only three human subjects. The tape is commercially available from Lectec Corporation, Minnetonka, Minnesota, as "Superpore ™ Tape". The adhesive consisted of an isoprene / styrene elastomer, a trimentin resin ester adherent resin and a salt of a long chain gi sic acid. The reinforcement consisted of polyester and cellulose fibers Adhesive and reinforcement absorb 147 percent by weight of water Results were reported as average in Table III Table III T-0-sßco * T-24-dry * T-0-wet * Tape Superpa-e ™ 0.3 0.63 0.07 'Expressed in Newtons / cm Table III shows that the "Superpore ™ Tape" does not have a peel strength, when applied to wet skin, as high as the tapes of this invention. It is noted that in relation to this date, the best method known to the Applicant for carrying out the said invention, is the one that is clear from the present description of the invention.

Having described the invention as above, property is claimed as contained in the following

Claims (8)

1. Claims 1 A sheet of adhesive sheet material, characterized in that it comprises a porous reinforcement with opposite sides, which is made of fibers, which absorb less than 4 weight percent of water, and a water-soluble pressure-sensitive adhesive, which is capable of absorbing no more than 10 percent by weight of water and which adhesive is discontinuously coated on one side of the reinforcement, to provide areas of pressure-sensitive adhesive interspersed with areas of uncoated reinforcement, of the reinforcement which are not coated by the adhesive consist of between 20 and 70 percent of the reinforcement area, where the porosity of the reinforcement is sufficient to provide an adhesive sheet material with a Gurley value of 0 to 15 seconds per 100%. ce of air.
2. 2. An adhesive sheet material according to claim 1, characterized in that the fibers are selected from the group consisting of multilayer fibers, coated fibers and homogeneous solid fibers.
3. 3. A adhesive sheet material according to claim 2, characterized in that the fibers are manufactured at least in part from a polymer selected from the group consisting of a polyolefin, substituted polyolefin, polyester, substituted polyester, polyamide, substituted polyamide, polyurethane and substituted polyurethane, wherein the substituent of any of the above substituted polymers is an aprotic pending group
4. 4 An adhesive sheet material according to claim 2, characterized in that the fibers are coated with a fluorinated chemical compound or a silicone.
5. An adhesive sheet material according to claim 1, characterized in that the amount of the pressure-sensitive adhesive coating on the reinforcement is at least about 2 mg per square centimeter.
6. An adhesive sheet material according to claim 1, characterized in that the areas of the reinforcement coated with the adhesive are not greater than about 5 mm in at least one dimension.
7. An adhesive material according to claim 6, characterized in that the areas of the reinforcement coated with adhesive are not greater than about 5 mm in two dimensions.
8. 8. An adhesive sheet material according to claim 1, characterized in that the pressure sensitive adhesive is a viscoelastic polymer selected from the group consisting of polyacrylate, polyolefin, polyether, polyisoprene, butyl rubber, natural rubber, polyurethane. , polyester and a block copolymer of butadiene and styrene, The adhesive sheet material according to claim 1, characterized in that: the reinforcement comprises a woven, cross-linked or non-woven, porous fibrous reinforcement with opposite sides, which consists of fibers that are selected from the group consisting of multilayer fibers having a surface layer that contains a hydrophobic agent, coated fibers having a surface coating of a hydrophobic agent and solid homogeneous fibers and wherein the areas of the pressure sensitive adhesive are of an individual size not greater than 5 mm in less one dimension, the amount of pressure sensitive adhesive coated on the reinforcement is at least 2 mg per square centimeter and the total area coated with pressure sensitive adhesive is 30 to 80 percent of the total area of reinforcement A method for adhering the adhesive sheet material according to claim 1, to a surface wetted with an aqueous liquid, characterized in that it comprises: applying to the wet surface the material of the adhesive sheet under conditions of sufficient time and pressure to cause that the aqueous liquid moves to you birds from the adhesive sheet material, the adhesive sheet material comprises porous fibrous reinforcement, having opposite sides, which is made of fibers which absorb less than 4 weight percent water, and a water-insoluble, pressure-sensitive adhesive, which is capable of more than 10 percent by weight of water and which adhesive is discontinuously coated on one side of the reinforcement, the coating provides areas The pressure sensitive adhesive interspersed with areas of the reinforcement without adhesive, the areas of the reinforcement which are not coated by the adhesive are between 20 and 70 percent of the reinforcement area, where the porosity of the reinforcement is sufficient to provide an adhesive sheet material with a Gurley value of 0 to 15 seconds per 100 cc of air.