MXPA98001712A

MXPA98001712A - Method of formation of films improved with openings, films resulting with openings and absorbent products that incorporate movies resulting with abertu

Info

Publication number: MXPA98001712A
Application number: MXPA/A/1998/001712A
Authority: MX
Inventors: A James William; G F Kelly William; Jaems Shimalla Charles
Original assignee: Mcneilppc Inc
Priority date: 1995-09-01
Filing date: 1998-03-02
Publication date: 1998-11-12

Abstract

The present invention relates to a film with openings to be used as a topsheet in absorbent products wherein the film has openings and includes a plurality of microholes and a plurality of large holes, a method for forming the film is described , as well as an absorbent product that incorporates the film with openings like a sheet

Description

METHOD OF FORMATION OF MOVIES IMPROVED WITH OPENINGS, FILMS RESULTING WITH OPENINGS AND ABSORBENT PRODUCTS THAT INCORPORATE FILMS RESULTING WITH OPENINGS FIELD OF THE INVENTION This invention relates to films with openings that have primary utility as a cover member for an absorbent article, and to methods and apparatus for forming said films with openings.

BACKGROUND OF THE INVENTION For many years it has been common to use non-woven fabrics as a cover member, or front layer, for products that are intended to receive body discharges, such as disposable diapers, sanitary napkins, adult incontinence devices, bandages for wounds and similar. Such fabrics have been formed, typically, by air-laying, carding, spunbonding and the like, and it is known to subsequently treat such fabrics to give them strength and integrity, for example, by the application of binders or by fiber entanglement, either mechanically or by the application of fluid forces. Since such fabrics are frequently formed of hydrophobic material, it is also known to subsequently treat said fabrics with surfactants to promote the passage of body discharges through the fabric. These fabrics have, or are perceived to have, convenient characteristics, such as the ability to breathe, mobility, softness, pleasant touch and tactile impression. One of the drawbacks associated with the front layers formed of a non-woven fabric, is that liquids, such as urine, menstruation, wound exudates and the like, which pass through the front layer and into the absorbent center, they tend to return through the front layer, particularly under pressure, and when the liquid in the absorbent center approaches the volumetric storage capacity of the center. For that reason and for others, it has been known, in the past, to use plastic films with openings such as the front layer in the absorbent articles. The following list includes descriptions of such films with openings in US and foreign patents granted, and in published patent applications: US Patent No. 3,632,269, Doviak and co-inventors, US Patent No. 3,929,135, Thompson and co-inventors, US Patent No. 4,324,276 , Mullane, U.S. Patent No. 4,351,784, Thomas and co-inventors, U.S. Patent No. 4,381,326, Kelly, U.S. Patent No. 4,456,570, Thomas and co-inventors, U.S. Patent No. 4,535,020, Thomas and co-inventors, U.S. Patent No. 4,690,679, Mattingly and co-inventors , U.S. Patent No. 4,839,216, Curro and co-inventors, U.S. Patent No. 4,950,264, Osborn, U.S. Patent No. 5,009,653, Osborn, U.S. Patent No. 5,112,690, Cohen and co-Inventors, U.S. Patent No. 5,342,334, Thompson and co-Inventors, U.S. Patent No. 5,352,217, Curro, U.S. Patent No. 5,368,910, Lang US patent No. 5,368,926, Thompson and co-inventors, US Patent No. 5,376,439, Hodgson and co-inventors, US Patent No. 5,382,245, Thompson and co-inventors, US Patent No. 5,382,703, Hohr and co-inventors, US Patent No. 5,383,870, Takai and co-inventors, US Pat. No. 5,387,209, Yamamoto and co-inventors, EP 0304617, Suda and coinventores, EP 0 598 204, Garavaglia and coinventores, EP 0626 158 Al, Coles and co-inventors, EP 0 626 159 Al, Taki and coinventores, EP 0 640 328, Tanaka and co-inventors, JP 3-286762 A, Yamamoto and co-inventors, WO 92/18078 Al, Colbert, WO 93/157091 Al, Turi and co-inventors, WO 94/18926 Al, Perry, WO 94/22408 Al, Langdon, WO 94/28846 Al, Steiger and co-inventors, WO 95/00093 A2, Osborn and co-inventors.

While some of those films with openings have worked reasonably well for the purposes for which they are intended, the vast majority of these films have real and perceived significant shortcomings. For example, even if such apertured films can allow fluid to pass easily through them, and can minimize the return of such fluid, those apertured films, however, tend to have the appearance, feel and feel of the film. touch of a movie, instead of a fabric. These film-like characteristics are considered negative by the consumer and, in this way, the absorbent products with films with openings as a front layer, have not had wide acceptance by the consumer. The main improvements in the film front layers with openings for absorbent products are described in the pending US patent applications, assigned to the same successor as the present, No, serial 08 / 417,404 and 08 / 417,408, of Turi and co-inventors , filed on April 5, 1995, as a continuation and division of serial No. 08 / 004,379, filed on January 14, 1993, as a continuation of serial No. 07 / 744,744, filed on October 14, 1993. August 1991 (corresponding to publication W0 93/15701 Al of the previous list). In the Turi and co-inventor applications mentioned above, a film with apertures and methods and apparatuses for forming the film is described, which impart to the film physical characteristics such as those of non-woven fabrics. This is achieved by supporting a film formed of stretchable thermoplastic polymer material, on localized support regions of a support member, and directing a fluid in the form of small diameter, high pressure columnar jets against the upper surface of the film, so that the unsupported portions of the film are directed down between the supporting regions, to cause the formation of micro-holes and fiber-like elements (fibrils) around them, to impart to the film with openings, physical characteristics of appearance, softness , feel and feel similar to those of a non-woven fabric. While such apertured films are a marked improvement over apertured films of the prior art, it is desirable to provide other improvements in such apertured films, for example, by improving the ability of those films to pass viscous fluids, such as the menstrual flow For the use of films with openings such as cover sheets for sanitary napkins, the cleaning-drying properties are highly desirable. This means that the sanitary napkin should appear clean and dry for the wearer, even after accepting a menstrual fluid flow. There are many factors that affect the cleaning-drying properties of a sanitary napkin, which include the opening characteristics and the open area of the sanitary napkin cover material. There is an exchange in the effects of the size of the openings of the film and the open area, on the properties of cleaning-drying. On the one hand, large openings allow the fluid to be transmitted more rapidly to the absorbent center. On the other hand, too large openings allow fluid to be transported back through the topsheet from the absorbent center (a phenomenon sometimes referred to as "return") and contact the wearer. Additionally, large open areas tend to allow staining of the absorbent center of the towel to be visible through the top cover and give the user the perception that the product has not kept it clean. To exhibit both the cleaning and drying properties, a top cover must have a carefully balanced combination of opening size and open area: sufficiently large openings quickly accept a menstrual fluid flow and allow it to pass through them to the absorbent towel center; but they must be small enough to mask the stain in the absorbent center below, to give the user the perception of cleanliness.

BRIEF DESCRIPTION OF THE INVENTION In accordance with one aspect of the present invention, films with openings of the type described in Turi patent applications and co-inventors, mentioned above, are improved by providing in said films larger openings and a sufficient open area, so that Viscous fluids, such as menstrual discharges, can easily flow through the film. These improved properties are imparted to the film by subjecting it to fluid forces in the form of streams or columnar jets from at least two series of holes; the orifices of a series having a diameter of more than 254 μm, and the fluid supplied to the orifices having a relatively low pressure of less than about 3515 kPa gauge, and the holes of at least one other series have a smaller diameter than or equal to 254 μm and the fluid supplied to them has a relatively high pressure of more than about 3515 kPa gauge. The present invention can be put into practice with a selective variation of the sequence to which the film is subjected to the fluid forces, from the low pressure and high pressure orifices; that is, first the low pressure, then the high pressure; or first the high pressure and then the low pressure; or other combinations or variations. The openings, for the most part, are irregular in shape and size. They are measured by various techniques that approximate the diameter, which can be expressed as the equivalent hydraulic diameter (DHE) or the equivalent circular diameter (DCE). The resulting apertured film has a combination of large apertures having DHE values of about 177.8 μm to 762 μm, and small sized apertures having average DHE values of about 25.4 μm to 177.8 μm. These films with openings have an open area in the approximate range of 3% to 13%. The improved apertured film of the present invention is preferably formed on a support member similar to that shown in Figures 17-19 of the Turi and co-inventor applications, mentioned above, which results in the film having a series of ridges. generally parallel, formed by lateral walls oriented generally vertically, which define a series of generally parallel valleys. The film thus includes alternating solid, or closed, generally parallel portions of the film, separated by open or open portions of the film, which contain the aforementioned combination of large size and small size openings. The openings of both sizes are formed as a result of stretching and stretching of the stretchable material between the localized bearing regions of the support member, as a result of the application of fluid pressure, and when the film is stretched, it undergoes thinning until it finally reaches the breaking point (ie, dissociation and fibrillation) to form the openings mentioned above. As with the apertured films described in the Turi and co-inventor applications, the openings are surrounded by a network of fiber-like elements, or microtiras of stretched plastic material. Such stretched fiber-like elements (fibrils) cooperate with the openings to impart to the apertured film the physical characteristics similar to those of non-woven fabrics. The fiber-like elements have lengths ranging from about 0.013 cm to about 0.127 cm; widths ranging from about 0.003 cm to about 0.089 cm; and thicknesses ranging from about 0.0006 cm to about 0.005 cm. In accordance with the present invention, films with openings of the type described in the aforementioned Turi applications and coauthors are modified so as to impart to the film the improved fluid distribution properties in the region of the film that has been subjected to to stretch, by deflection downwardly of the film towards the depressed region of the supporting member, during the formation of the film. The method for forming the film with apertures from a stretchable thermoplastic polymer material, according to the invention, comprises the steps of providing a starting film comprising the stretchable thermoplastic polymer material and having a top surface and a bottom surface. A support member comprising support regions located to support the starting film is provided. The support member has depressed regions within which the film can be deformed by applying fluid forces to it. Means are provided to allow the applied fluid to be transported away from the support member. The starting film in the supporting member has portions of the lower surface of the film that are in contact with the supporting regions of the supporting member. The upper surface of the film faces away from the supporting member. A fluid in the form of columnar streams, coming from at least two series of orifices, is directed against the upper surface of the starting film, in a contact zone, ie, an area in which the film is subjected to the forces of fluid currents. The holes of the first series each have a diameter greater than 254 μm and the fluid supplied to them has a pressure of less than 3515 kPa gauge, to cause the formation of large holes in the starting film. The holes of the second series each have a diameter less than or equal to 254 μm and the fluid supplied to them has a pressure of at least 3515 kPa gauge, to cause the formation of microholes in the starting film. The film is removed from the contact area and the film with openings is now separated from the support member.

Other aspects and advantages of the present invention will become readily apparent from the detailed description that follows, from the accompanying drawings and from the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic, side elevational view of a production line for forming the apertured film according to the present invention. Figure 2 is a schematic, side elevational view, on a larger scale, of the unwinding section of the apparatus for producing the apertured film of the present invention. Figure 3 is an enlarged, side elevational view of the aperture-forming section of the apparatus used to form the apertured film of the present invention. Figure 4 is an enlarged, side elevational view of the water stripping section of the apparatus used to form the apertured film of the present invention. Figure 5 is an enlarged, side elevational view of the dryer section of the apparatus used to form the apertured film of the present invention. Figure 6 is an enlarged, side elevational view of the divider / rewinder section of the apparatus used to form the apertured film of the present invention.

Figure 7A is a schematic view of a strip with holes used in the apparatus to form one of the apertured films of the present invention. Figures 7B, C, D and E are enlarged views of hole patterns that can be used in the apparatus for forming apertured films of the present invention. Figure 8 is an exploded perspective view of a starting film, located on a support member for processing according to the present invention. Figure 9 is a top plan view of the support member shown in the lower portion of Figure 8. Figure 10 is an enlarged sectional view taken along line 10-10 of Figure 9. Figures 11A-D they are similar to the figure , showing sequential steps in the stretching of the starting film to form the openings according to the teachings of the present invention. Figure 12 is a top plan photograph of an apertured film formed in accordance with the present invention, at a magnification of 7.5 times. Figure 13 is an elevational view of the apertured film of Figure 12. Figure 14 is an end elevational view of the apertured film of Figure 12, at a 15-fold magnification.

Figure 15 is a top plan view of another apertured film formed in accordance with the teachings of the present invention, at a magnification of 7.5 times. Fig. 16 is an end elevational view of the apertured film of Fig. 15. Fig. 17 is an end elevational view of the apertured film of Fig. 15 at a 15-fold magnification. Figures 18A and B are photographs taken at a 10-fold magnification, of the apertured film formed in accordance with the invention, formed from an enhanced release film, having its female side against the associated forming member; wherein the film was subjected to the formation of openings by a sequence of three strips of holes; the first holes being relatively large according to Figure 7D; having the second and third holes relatively small according to Figure 7A (Figure 18A is its side against which the water jets were directed, Figure 18B being its side positioned against the associated forming member). Figures 18C and D are photographs taken at a 10-fold magnification, of the apertured film formed in accordance with the invention, formed from an enhanced starting film having its female side against the associated forming member; wherein the film was subjected to the formation of openings by a single strip of holes having relatively large holes according to Figure 7D (Figure 18C shows its side against which the water jets were directed); Figure 18D showing its side positioned against the associated training member). Fig. 19 is a block diagram showing the various steps of the process for producing the apertured film according to the present invention. Figure 20 is a perspective view of a sanitary napkin consisting of a film with openings according to the present invention; and Figure 21 is a view, partially in section, taken along line 21-21 of Figure 20. Figure 22 is a graph illustrating the distribution of aperture sizes in a film sample with an aperture made at 6,151.25 kPa gauge. , in an apparatus using three strips with holes, each of which has a plurality of holes; all the holes having a diameter of 127 microns. Figure 23 is a graph illustrating the distribution of aperture sizes in a film sample with apertures, made in an apparatus comprising a single strip of holes, having a plurality of holes, each with a diameter of 508. μm in diameter; said strip of holes being shown in figure 7C. Figure 24 is a graph illustrating the size distribution of openings in an apertured film sample, made in an apparatus comprising a first strip with holes (shown in Figure 7C) having a plurality of holes; all of which have a diameter of 508 μm; and a second strip of holes, downstream of the first strip, wherein the second strip (shown in Figure 7A) has a plurality of holes, all of which have a diameter of 127 μm. Figure 25 is a graph illustrating the distribution of aperture sizes in an apertured film sample, made in accordance with the invention; and Figure 26 is a graph illustrating the results of the comparison wherein the spacing of the holes comprised in the orifice strip is varied.

DESCRIPTION OF THE PREFERRED MODALITIES Although the present invention is capable of being incorporated in various forms, it is shown in the drawings and the presently preferred embodiments will be described below, it being understood that the present description should be considered as an exemplification of the invention, and is not intended that limits the invention to the specific modalities illustrated. Referring now to the drawings, Figure 1 is a schematic side elevational view of a mode of a production line that can be used to produce apertured films according to the teachings of the present invention. As indicated by the direction arrow, the process flow proceeds from right to left in Figure 1. As shown in Figure 1, the production line has five main stations: a film unwinding station 30; a station 40 for forming openings; a water removal station 50; a drying station 60 and a cutting, rewinding and surfactant application station 70. As shown in FIG. 2, two rolls 31 of starting material material 33 are mounted in the film unwinder station to rotate on the frame F. The film coming from the rolls 31 is fed on the guide rolls, and towards festoon 32 which has an automatic tension control system (closed loop). The film 33, under suitable tension, for example, between 1.78 to 17.85 kg / linear meter, leaves the festoon 32 and proceeds towards the opening forming station 40. While many different starting film materials are suitable for use in the present invention, one of the preferred materials is a polyethylene film, commercially available from Exxon Chemical, under the product designation EMB-631. This film is a white pigmented polyethylene film, enhanced. The polyethylene component consists of a mixture of 40% by weight of low density polyethylene and 60% by weight of linear low density polyethylene. The film has 6.5 wt.% Titanium dioxide. The starting film is highlighted with a diamond pattern at 64.9 lines per centimeter, to give on one side of the film, called the male side, a plurality of discontinuous, observable protrusions, separated by an interconnected, continuous weighted pattern. The other side of the raised starting film, called the female side, has a plurality of observable cup-shaped depressions, separated by a continuous, interconnected rib pattern. The cup-shaped depressions on the female side of the film are in respective coincidence with the protuberances on the male side of the film. The starting film is electrostatically treated with a corona discharge treatment on one side, preferably on the male side. The film has a terminal tensile strength of 1750 g in the machine direction (with 500% bursting elongation) and 1300 g in the transverse direction (with elongation to bursting of 650%), when determined using the test ASTM D-882. The process for forming the film of the invention can be intermittent or continuous, generally similar to the intermittent and continuous processes described in co-pending application Serial No. 08 / 417,404. The preferred embodiment is a continuous apparatus, as further described herein.

With reference to Figure 3, the film 33 is shown coming from the unwinding station, entering the opening forming station 40, on its right side. The aperture forming station 40 includes a honeycomb-type supporting drum 41, rotatably mounted in a frame Fl. The drum 41 has a three-dimensional forming support or member, described in detail below, mounted on its outer peripheral surface. Four multiple 42 water jet are also supported on the frame Fl and four suction slots, one for each manifold 42, are provided inside the supporting drum, and will also be described in detail here below. The suction grooves are mounted inside the drum and are aligned with the water jet manifolds located outside the drum. Each water stream manifold comprises a metal strip, hereinafter often referred to as the orifice strip, having a plurality of holes that have a predetermined size and spacing. Specific examples of said orifice strips are described in more detail below. A given manifold 42 may comprise one or more orifice strips. The orifice size preferably remains constant for each strip. However, the size of the hole may vary in a given strip. The distance between the lower surface of the orifice strip and the outer surface of the apertured drum supporting member is preferably in the range of between 1.27 cm and 2.54 cm.

Pressurized hot water is pumped to manifolds 42, and pressurized water exits through the plurality of orifices in the orifice strip, in the form of columnar water jets. The water pressure in each manifold 42 can be regulated separately. The entering film 33 is passed on a guide roller 43, and then on the outer periphery of the ridimensional forming member, mounted on the supporting drum 41. The columnar water streams coming out of the orifice strips collide on the film and make that the film flexes downward in the depressed regions of the support member mounted on the supporting drum, thereby causing the stretching of the film and its breaking into a plurality of holes of irregular size. Film 44, now with openings, leaves the aperture forming station 40 on its left side, and passes to the water removal section. As shown in FIG. 4, in the water removing section 50, two water-removing drums 51 are mounted to rotate on the frame F3. The drums 51 have a honeycomb configuration, and each drum has two vacuum grooves associated therewith, capable of establishing a vacuum of up to 17.78 cm Hg. Twelve air blades 52 are provided, six air blades provided for each drum 51. The suction grooves associated with the water removing drums 51 are located internally with respect to the drums, while the air blades 52 are located outside of the drums. the drums 51. Excess water is removed from the film with openings, causing high velocity air to strike from the knives 52 and by suction through the suction grooves of the drums 51. The air knives 52 operate at a scale of air temperature between 65.5 ° C and 82.2 ° C. The total air flow through the twelve air blades 52 is between about 471.9 to about 943.8 liters / second per 0.3048 m width of the apertured film. Film 53 without water leaves the water removing station 50 on its left side, and passes to the dryer section. With reference to Figure 5, the air dryer station 60 is illustrated including two vacuum drums 61, mounted on the frame F4. Each drum 61 has a suction groove, which has an arc of 300 ° around the drum. Twenty air blades 62 are placed out of each vacuum drum 61, and the air blades 62 operate at a temperature between 65.5 ° C and 82.2 ° C. The combined air flow for the forty air blades 62 is between about 2,359 and about 3,303 liters / second per linear 0.3048 m width of the apertured film. The pressure drop caused by the vacuum in the drums 61 is about 50.8 mm of water, measured through the film. The dry film 63 leaves the dryer section 60 on its left side and passes to the divider / rewinding section ra 70. Referring now to Figure 6, the film 63 from the dryer section enters the divider / rewinder station 70 , on your right side. A divider 71, consisting of divider blades of the marked cut type, spaced, cuts the dry film to the desired width. The film with dry and split openings then passes to a surfactant applicator 72, where a suitable surfactant, e.g., Tween 20, is applied to the film by contact coating. Preferably, the surfactant is provided in an aqueous solution consisting of about 48.8 ± 1.5 percent surfactant. In an exemplary embodiment of the invention, the roller coating speed of the surfactant is 15.18 ± 7.62 cm per minute. Preferably, the surfactant is applied to the male side of the film. The parameters mentioned above result in an addition of surfactant solution of 0.25 mg / 2.54 cm ± 0.07. Referring to Figures 7A-7E, the columnar water jets are discharged from one or more strips of holes, which have a plurality of holes. Preferably the holes are formed by piercing a precursor metal strip to form cylindrical holes. However, it is anticipated that holes can be used in various ways. Figure 7 shows a strip of holes 80 for supplying columnar water jets, each of which has a relatively small cross-section to form holes in the film. The holes 82 in the manifold have a diameter of 127 μm and are separated by 0.50 μm. The multiple strip can be obtained from Nippon Nozzle Co., of Kobe, Japan. Figures 7B-7E show orifice strips for producing columnar water jets, each of which has a relatively large cross-section, to form large-sized holes in the film. Figure 7B shows a strip of holes having two rows 84, 86, of holes 84 ', 86', which are spaced on opposite sides of a tangent center line. The holes in each row have a diameter of 381 μm and are spaced at 0.55 μm, from center to center. The separation of the orifices in the upper row deviates from the separation of the holes in the lower row, by 0.279 μm. The strip contains 35.78 holes per centimeter. Figure 7C shows a strip of holes having two rows 88, 90 of holes 88 ', 90', which are spaced on opposite sides of a central tangent line. The holes in each row have a diameter of 508 μm and are spaced at 0.81 μm. The separation of the holes in the upper row deviates from the separation of the holes in the lower row by 0.406 μm. The strip contains 24.60 holes per centimeter. Figure 7D shows a strip of holes having two rows 92, 94 of holes 92 ', 94', which are spaced on opposite sides of a central tangent line. The holes in each row have a diameter of 635 μm and are spaced at 0.96 μm. The separation of the holes in the upper row deviates from the hole spacing in the lower row by 0.48 μm. The strip contains 20.70 holes per centimeter. Figure 7E shows a strip of holes for supplying columnar water jets, each of which has a relatively large cross-section to form large-sized holes in the film. Each of the holes has a diameter of 0.635 mm and are spaced at 2.10 mm, from center to center. While the orifice strip shown in Figure 7E is suitable for forming the film according to the present invention, the use of hole strips as shown in Figures 7B-7D is currently preferred for use in combination with one or more Orifice strips that have relatively small holes for the formation of micron-sized holes. The small holes (see Figure 7A) preferably have a diameter less than 254 μm. The larger orifices (see Figures 7B-7E) preferably have a diameter greater than 254 μm. An apparatus for forming apertured films of the present invention is described in detail in co-pending patent application Serial No. 08 / 417,404. The apparatus for forming the film of the present invention contains certain additional aspects, including a second series of orifice strips, as discussed above with reference to Figures 7B-7E. The pressure of the water supplied to the small orifices is generally greater than 3515 kPa gauge, preferably of the order of 3515 to 11,248 kPa gauge or more. The water pressure supplied to the large orifices is generally less than 3515 kPa gauge, preferably of the order of 878 to 1406 kPa gauge. In a preferred embodiment, the equipment with openings consists of a honeycomb type drum, a three-dimensional forming member, several water jet manifolds, and corresponding suction grooves, disposed in the interior and sequentially along a section of the circumference of the drum. The forming member is an engraved sleeve, as shown in Figures 8-10, which is mounted on the honeycomb drum. The suction grooves are mounted inside the drum and are aligned with the water jet manifolds, located outside the drum. Each water jet manifold contains a metal strip having a plurality of holes. For a given manifold, the hole size remains constant throughout the strip. The distance between the orifice strip and the surface of the engraved sleeve is preferably between 1.27 cm and 2.54 cm. The manifolds are pressurized by pumping hot water. Pressurized water exits through the series of holes in the orifice strip, thereby creating substantially columnar water jets. The energy of the columnar hot water jets, which collide on the film, causes the film to be contoured towards the surface of the engraved sleeve, thereby causing the film to stretch and break into a multiplicity of holes of irregular size. The pressure and temperature of the water supplied to each manifold can be regulated separately. The procedure parameters are as follows: Line speed (m / min): 45.72 - 182.88 Water temperature: 68.3 - 73.8 ° C. Maximum number of multiples used: 3 Distance between the manifold strip and the sleeve surface: 1.27 cm - 2.54 cm. Multiple of low pressure: Number of multiples: 1 Scale of orifice sizes (mm) 0.368 to 0.762. Pressure (kPa gauge): 1054.5 ± 175.25 Water flow: 0.504 ± 0.126 liters per hour per 2.54 cm of orifice strip. Vacuum suction slot (Hg mm) 127 ± 50.8 mm (-17 ± 10.2 kPa). Multiple high pressure: Number of multiples: maximum, 2. Scale of hole size (mm) 0.127 to 0.177 Pressure (kPa gauge) 8084.5 ± 2460.5 Water flow 0.056 ± 0.013 liters / hour for 2.54 cm of hole strip.

Vacuum of the suction slot (Hg mm): 127 ± 76.2 (-17 ± . 2 kPa). Sequence of use of the manifold: The water jet manifolds and their associated orifice strips may be arranged in a variety of sequences with respect to the direction of continuous movement of the film on the drum. Any of the following five sequences can be used to open the film: 1. Low pressure, high pressure; 2. Low pressure, high pressure, high pressure, 3. high pressure, low pressure, 4. high pressure, low pressure, high pressure 5. high pressure, high pressure, low pressure. Referring to Figures 8 to 10, the forming member is a three-dimensional surface having a plurality of radially extending supporting elements, which rise from the base of the forming member or support. These elements are substantially similar to the corresponding elements described in co-pending patent application Serial No. 08 / 417,404. Figure 8 is an exploded perspective view of the starting film 100, supported on the support member 102. The starting film may be embossed or not embossed. Alternatively, a portion 104 of the starting film 100 comprises protrusions 106 and regions without protuberances 108, as shown in the upper portion of Figure 8. The supporting member 102 comprises a base portion 110 having an upper surface 110a and a lower surface 110b. The support member 102 further comprises a plurality of openings 112, which run through the thickness of the base 110 from the upper surface 110a to the lower surface 110b. As will be seen below, openings 112 are provided to allow the removal of water during the manufacture of the apertured film according to the invention. The support member 102 also includes a plurality of radially extending support elements 114. These supporting elements comprise a base 116 that coincides with the plane of the upper surface 110a of the portion 110 and a pair of side walls at an angle 118, 120 (best seen in Figures 9 and 10). The side walls 118, 120 extend outward from the base 116 to be in an intermediate portion or rim 122. The support elements 114 are aligned in parallel and spaced equidistantly from each other. They can run parallel, perpendicular or at any angle, with respect to the sides of the supporting member. As shown in FIGS. 8 and 9, these support elements 114, when viewed in planar, generally have a sinusoidal or corrugate-like configuration. It will be understood that the supporting elements may be provided in other configurations, for example, in a straight line, in a zigzag pattern and the like. A detailed description of the forming member is disclosed in co-pending patent application Serial No. 08 / 417,404. Referring to Figures 11A-D, the advancement of stretching of the starting film 124 is shown to form the openings according to the teachings of the present invention. Referring to figure HA, the starting film 124 is initially laid on the support member. Referring to Figure 11B, the film 124 deforms in response to the application of the columnar water jets, and expands (i.e., stretches), downward and partially within the space between the supporting elements. Referring to Figure 11C, as the film 124 is stretched, it thins. Referring to Figure 11D, as the film is further stretched and thinned, it begins to break and form holes 126. This procedure is further described in the pending patent application Serial No. 08 / 417,404, where describes the formation of micro-holes surrounded by microstrips of film material, or fibrils. Due to the vertical elements on the forming member, the film of the present invention is dilated (ie, receives significant di-directionality in the z-direction, with respect to the original thickness of the film without openings, precursor) immediately exiting the process. In some processes of the prior art, dilation in the z direction must be achieved in a separate embossing step (see, for example, U.S. Patent No. 4,609,518). An expanded upper sheet limits the contact between the user and the absorbent layer and, in this way, increases the sensation of dryness in the products that incorporate it. In the films, the absorbent products and the methods described herein, the holes in the film include microholes and large holes, or may only include large holes. It is believed that the microholes are formed primarily by the stretching of the film material, in response to the application of the columnar water jets coming from the smaller orifices of the orifice strip discussed above. It is believed that the large-sized holes, also formed from the stretching of the film material, are formed primarily in response to the application of the columnar water jets coming from the larger orifices, rather than the smaller orifices, of the hole strip discussed above. The resulting apertured film has a combination of large holes or openings, having average DHE values of about 177.8 microns to about 762 microns, and apertures or holes of small size, sometimes called micron size holes, which have DHE values averaged around 25.4 to around 177.8 microns. These films with openings have an open area in the approximate range of 3% to 13%. It has been found that the use of orifice strips having holes whose diameters vary from about 254 to 635 microns, results in the formation of apertures in the film having a DHE from about 177.8 to about 431.8 microns. The fibrils surrounding and defining the micro holes and the large size holes are described in detail in co-pending patent application Serial No. 08 / 417,404. The fibrils have lengths ranging from 0.013 cm to about 0.127 cm; widths ranging from 0.003 cm to around 0.089 cm; and thicknesses ranging from about 0.006 cm to about 0.005 cm. The photographs of Figures 12-18A, B show the combination of microholes and large size holes, of a film with openings made in accordance with the invention. The photographs of FIGS. 18C, D show large-sized holes in an apertured film made in accordance with the invention. The combination of large holes and microholes of the dimensions discussed above, produces an improvement in the cleaning and drying properties of the film, when used as a cover sheet for a sanitary napkin. The resulting open area is on the scale of 3 to 13%. In the prior art film having only microholes (see co-pending application Serial No. 08 / 417,404) when using columnar water jets with a diameter of 127 microns, the resulting apertured film has microholes with an average DHE of 76.2 micras, and has an open area of around 3%. The increased aperture size and the increased open area in the apertured film, which has large holes in combination with microholes, according to the invention, provides an improved aperture size and open area, so as to give in an advantageous balance; the openings large enough to quickly accept a flow of menstrual fluid and allow it to pass through them to the absorbent center of the towel, but small enough to mask the stain on the absorbent pad, to give the consumer the perception of cleanliness. Thus, the absorbent products of the present invention, made with the apertured films of the present invention, have improved cleaning and drying properties. In a preferred embodiment of the invention, the starting film has its openings formed by columnar water jets of large diameter and low pressure and by columnar water jets of small diameter and high pressure. This combination of both high and low pressure jets produces larger openings and larger open area than films made with small diameter and high pressure jets only. Films made using this modality also appear softer to the wearer than films made only with large diameter, low pressure jets. Figure 19 is a block diagram showing the various steps in the process for producing the novel apertured films of the present invention. The first step in the process is to place a piece of thin, stretchable film of thermoplastic polymer material on a support or support member (box 1). The supporting member, with the stretchable film on it, is passed under high pressure fluid ejector nozzles (box 2). The preferred fluid is water. The water is transported away from the support member, preferably using a vacuum (box 3). Water is removed from the film, suction being preferred for this purpose (box 4). The film is removed with openings and without water from the support member (box 5). The waste water is removed from the film with openings, for example by applying a stream of air (box 6). Then the surfactant is applied to the film with openings (box 7). The film is then rolled with openings to await its use, or used as is or as a structural component of another product, such as a sanitary napkin, a disposable diaper or a wound dressing (box 8). Referring to Figures 20 and 21, a sanitary towel 130 is shown comprising an absorbent core 132 of wood pulp fibers, a thin, fluid impermeable auger film 134, and a cover material 136, which can be any the films with openings of the invention. Preferably the cover film material has the structure shown and described herein. The barrier film 134, which may comprise, for example, a thin polyethylene film, makes contact with the lower surface of the absorbent core 132, and runs partially along the longitudinal sides of the absorbent center. The cover material 136 has a length somewhat larger than the length of the absorbent center, and is wrapped around the absorbent center and the barrier film, as shown in Figure 21. The longitudinal edges of the cover material are overlapped and sealed to each other on the lower surface of the towel, in the usual manner. In the illustrated embodiment, the cover material is sealed to itself at the ends 138, 140 of the sanitary napkin. As illustrated in Figure 21, the sanitary towel 130 has a layer of adhesive 142 to adhere the towel to the wearer's undergarment. The adhesive 142 is protected before use by a detachable, detachable strip 144.

EXAMPLE 1 In one embodiment of the apertured film according to the invention, the starting material is an embossed film, supplied by Exxon Chemical under the designation EMB-631, and having a thickness of 24.13 microns. The film is treated with corona discharge on its male side. The film is placed on the forming member shown in Figures 8-10, which is mounted on a supporting drum, such as described in the pending applications Serial No. 08 / 417,404 and 08 / 417,408, of Turi and co-inventors, with the male side of the film, treated with a crown, looking away from the forming member. Two manifolds were used to direct columnar water streams to the film. The first, or multiple upstream, has the hole configuration shown in Figure 7D of the drawings; that is, there are two deviated rows 92, 94 of holes 92 ', 94', each hole having a diameter of 0.635 mm. The holes are spaced at a distance of 0.965 mm from center to center, to give a total of 20.70 holes per centimeter. The second, or multiple downstream, has the hole configuration shown in Figure 7A of the drawings, i.e., there is a single row of holes, each of which has a diameter of 0.127 mm. The holes are spaced at 0.508 mm on a center-to-center basis. There is a total of 19.68 holes per centimeter. Water is supplied at a temperature of 73.8 ° C at a pressure of 1159 kPa gauge to the first manifold, and at a pressure of 9842 kPa gauge to the second manifold. The film is passed under the manifolds at a speed of 132.5 m per minute.

The suction pressure inside the drum is 1270 mm of water. The water is removed from the film with the apparatus shown in Figure 4, and dried with the apparatus shown in Figure 5. After drying, the male side of the film is coated by contact with a 48.8% Tween solution. -20 in water, at a solution addition of 0.25 mg / 6.35 cm2. Subsequent lamination of the film effects the transfer of the surfactant solution from the corona treated male side to the female side. After the surfactant solution is finally dried, the film has a crude surfactant addition (including all film surfaces) of 0.12 mg / 6.35 cm2. The resulting apertured film has an air permeability of about 23.75 1 / sec / cm2, at a pressure difference (/ \ P) of 12.7 mm of water. The film has a measured open area of 6.24% and an average CDE of 254-279 microns. The DCE (equivalent circular diameter) is a calculated opening diameter that is based on a measurement of the area of the opening. The area is measured using the peripheral equipment and the application program described, to measure the DUS in the pending patent application Serial No. 08 / 417,404. The formula for DCE is: _4A DCE =, where A is the measured area of an abe rtura. There is an average of 196.8 openings per square centimeter. The volumetric thickness is 368.3 m.

EXAMPLE 2 Another embodiment of the apertured film of the invention was made using the same starting film and the same forming member used in Example 1. The linear velocity was 45.72 m / min. Two manifolds were used to direct columnar water streams to the film. The first, or multiple upstream, has the hole configuration shown in Figure 7C of the drawings, i.e., there were two offset rows 88, 90 of holes 88 ', 90', each of the holes had a diameter of 0.508. mm. The holes are spaced at a distance of 0.812 mm from center to center, to give a total of 24.60 holes per centimeter. The second, or multiple downstream, has the orifice configuration shown in Figure 7A of the drawings, i.e., there is a single row of holes, each of which has a diameter of 0.127 mm. These holes are spaced at 0.508 mm on a center-to-center basis. There is a total of 19.68 of said holes per centimeter. Water is supplied that has a temperature of 71.1 ° C, at a pressure of 1054 kPa gauge to the first manifold, and at a pressure of 10545 kPa gauge to the second manifold. The drum has a vacuum of 152.4 mm Hg (-20.4 kPa). In the water elimination section there were six water eliminating blades and a vacuum of 101.6 Hg. The air temperature for the first series of air blades was 82.2 ° C. The air temperature for the second series of air blades was 48.8ßC. There were two film drying cylinders, and each cylinder had five blades of hot air. The temperature of the hot air for the blades was 65.5 ° C, and the vacuum was less than 25.4 mm of water. The apertured film produced according to example 2 was analyzed with a microscope. The open area, the hole size distribution and the total aspects (number of holes) were measured by image analysis techniques, with the following results: Open area. of DHE * DCE Dev. of Ta (tedia) account. Ferris wheel .-- (tedia) (tedia) ferris wheel .-- aperture. 6. 19 * 0.68 193.29 275.59 265.39 0.544 I * ticras ticras ticras * DHE is measured as it is discussed in the application for a patent pending in serial No. 08 / 417,404, which is incorporated herein by reference. The characteristics of the orifice strips used in the experiments described below are shown in Table 1.

TABLE 1 CHARACTERISTICS OF HOLES STRIPS Taiaño ID of No. of rows Separation inNo. of orifices the orifice strip, - of holes orifices, by strip, by ct of ori (in ??). - by row in the row (of strip of holes, orifices - center by center, ll). to 0.127 1 0.508 19.68 b 0.254 2 0.381 52.36 c 0.381 2 0.558 35.78 d 0.508 2 0.812 24.60 e 0.635 2 0.965 20.70 f 0.635 1 2.108 4.72 EXPERIMENTATION WITH INTERMITTENT MOVIE TRAINING The apparatus for the intermittent formation of apertures in film, used in the experiments reported in the following Table 2, was similar to that shown in Figure 3 of the drawings. However, only one water manifold 42 was used, and only one of the available vacuum slots was used. Each of the strips with holes, marked "b" to "f" in table 1, was mounted, in turn, in the single water jet manifold, and was used to form one or more films with openings, as shown in table 2. The starting film and the forming member were the same as those used in example 1.

A piece of starting film was mounted on the outer surface of the forming member, by a series of pins projecting from the forming member. The honeycomb support drum was rotated so that the mounted film was out of line with the single strip of holes. Vacuum was applied to the interior of the honeycomb drum. Hot water under pressure was supplied to the manifold. The motor of the honeycomb drum was rotated to pass the starting film once under the hole strip. The resulting film was removed from the forming member and air dried. The process conditions used to form the films and the properties of the resulting film are shown in the following Table 2.

TABLE 2 EXPERIMENTS OF INTERMITTENT TRAINING OF MOVIE OPENINGS Eg Pressure ID Tetp. Empty * VelociÁrea Diitetro Ho. Orifi water of the a- (di-hydraulic-hydraulic ti.) (kPa) .- gua * c water). pelit (t) equals (• / tt (DHE)? edia • in) ÍM) » b 2460.5 71.1 1524 45.72 3.6 271.78 b 3866.5 71.1 1524 45.72 6.5 261.62 b 7030.0 71.1 1524 45.72 8.5 195.58 c 1406.0 71.1 1524 45.72 2.9 297.18 c 2812.0 71.1 1524 45.72 8.7 414.02 c 3866.5 71.1 1524 45.72 11.7 363.22 TABLE 2 (continued) Eg Preset ID Tetp. Vacuum * Velociñrea Diitetro No. orifi of water of the a- (of dehydrohydraulic nature cio.- (Wa) .- gua * < water). pelícuta (l) equals (1 / tt (DHE)? edia lin) (μt) " 7 5975.5 71.1. 1524 15.72 11.5 220.98 8 1124.8 71.1 L 1524 15.72 1.5 281.94 9 1757.5 71.1 1524 < 15.72 8.1 434.34 2460.5 71.1l 1524 '15.72 9.4 373.38 11 3866.5 71.1 [1524 15.72 13.2 374.98 12 1054.5 71. L 1524 45.72 2.0 256.54 13 1687.2 71.1l 1524 15.72 7.4 378.46 14 2636.2 71. L 1524 15.72 12.8 436.8 14a 1054.5 71. L 1524 45.72 3.5 330.2 (1) 14b 1406.0 71.1 L 1524 45.72 5.71 325.1 (1) 14c 1757.5 71.l 1524 45.72 6.0 292.1 (1) * The value of the vacuum is in mm of water below the atmospheric pressure. ** The open area and the DHE were measured according to the method described in co-pending patent application Serial No. 08 / 417,404, which is incorporated herein by reference. (1) = DCE. The data indicate the following tendencies: _ increase the fluid pressure with a strip of holes of a given size, increases the open area.

Increasing the orifice diameter increases the open area at a given fluid pressure. Due to the stretching of material that occurs during the process of forming the openings, the weight per area of the film is reduced to about 15.93 g / m, which is 65% of the initial weight of film per unit area. When the 0.355 mm, 1.27 mm, 1.57 mm, and 1.90 mm diameter strips with holes of 0.635 mm diameter were used, from table 8, the open area decreased from 13.1% to 12.0, 11.2, and 10.1%, respectively.

EXPERIMENTATION WITH CONTINUOUS MOVIE TRAINING Other additional embodiments of films were made according to the present invention, using the starting film, the forming member and the general procedure of example 1. The characteristics of the used orifice strips are described in table 1 above. All operations were done using water at 71.1 ° C, with the male side, treated with corona, of the starting film, looking away from the forming member. The number of hole strips used and their characteristics and processing conditions are shown in the following table: TABLE 3 EXPERIMENTS OF CONTINUING FORMATION OF FILM OPENINGS Orifice strip Orifice strip Orifice strip No. 1 Ho. 2 No. 3 Pressure ExpedID Pressure ID Pressure Speed ID - strip of (kPa) strip of (kPa) strip of (kPa) liNo.- orifiorifiorifineal, cios. - cios. - cios. - (• / • in) d 1054.5 36.57 16 d 1054.5 to 7030.0 36.57 17 d 1054.5 to 7030.0 to 7030.0 36.57 18 to 7030.0 36.57 19 to 7030.0 to 7030.0 36.57 to 6151.2 to 6151.2 to 6151.2 36.57 21 to 6151.2 to 6151.2 to 5151.2 45.72 22 to 7030.0 d 1054.5 36.57 23 to 7030.0 d 1054.5 to 7030.0 36.57 After air drying, the films were coated by contact with an aqueous solution of Tween 20 surfactant, at a concentration of 48.8% on the male side, corona treated, to produce a crude surfactant addition of 0.12 mg / 6.45. cm2 of film, as described above with respect to example 1. Films with openings produced in these experiments were evaluated for air permeability, opening size, open area, impact through them and the flexure length (a measure of the stiffness of the film). Air permeability was tested according to ASTM D737. The size of the film aperture and its open area were determined and used to calculate the equivalent circular diameter (DCE). The impact through them is a measurement of the time required for 5 cc of a test fluid to be absorbed through the film supported on milled cottonwood pulp. The test fluid is a mixture of 75% by weight of defibrinated bovine blood and 25% by weight of a 10% by weight aqueous solution of polyvinylpyrrolidone (Povidone K-90 from GAF). The length that is flexed in the machine direction (DM) and in the transverse direction (DT) was measured in accordance with ASTM D1388. The properties of the film produced in continuous operations are shown in tables 4-7 below.

TABLE 4 PROPERTIES OF THE CONTINUOUS FILM WITH OPENINGS: AIR PERMEABILITY Experiment No. Air permeability, l / sec / cm2 to 12.5 mm of water, \ P) L 15 10,185 16 16,282 17 18,031 18 7,821 19 10,502 20 12,695 TABLE 4 (continued) Expedition No. Air permeability, 1 / sec / cm2 to 12.5 mm of water, \ P) 21 12,475 22 15,667 23 15,546 The data in Table 4 show that the combination of large diameter and small diameter holes (experiments 16, 17, 22 and 23) produces an open, more permeable film, than films made with small diameter holes only (experiments 18- twenty-one). It is believed that the use of large diameter holes, even if used at lower water pressure, is the primary cause for the creation of large holes. Additionally, it is believed that the use of smaller diameter holes is the primary cause for the creation of smaller micro holes.

TABLE 5 PROPERTIES OF THE MOVIE CONTINUES WITH OPENINGS: OPENING AREA AND OPEN AREA TABLE Do not . of DCE p roDeviation Open area rNo. of open medium, - of non-rmata, (%). - - ras / cm2 ment. μm EC, μm. - 418.08 257.04 4.55 77.55 16 218.94 234.18 5.34 202.75 17 189.99 215.13 5.34 281.49 18 118.11 67.56 2.31 442.91 19 115.06 67.31 2.48 505.11 101.60 57.15 2.38 643.70 21 105.66 62.99 2.53 598.03 22 164.84 141.98 4.15 317.32 23 174.75 156.97 4.88 337.00 The data in table 5 show that the combination of large diameter holes and small diameter holes (experiments 16, 17, 22 and 23) produce a film with larger aperture size and increased open area, compared to films made with small diameter holes only (experiments 18-21). Figures 22, 23 and 24 are graphs showing the distribution of aperture sizes of films produced in these experiments, with a strip of holes of 127 microns in diameter (experiment No. 20), a strip of holes of 508 microns in diameter (Experiment No. 15) and the combination of a strip of holes 508 microns in diameter followed by a strip of holes of 127 microns in diameter (experiment No. 16), respectively (see Table 3 above). As seen in these graphs, aperture films produced with orifice strips of different diameters have aperture sizes that reflect the effects of several of the individual orifice diameters. The film (experiment No. 20) produced with a strip of holes of 127 microns in diameter has only openings most of which have a diameter of less than 254 microns (see Figure 22). The film (experiment No. 15) produced with a strip of holes 508 microns in diameter only, has a wider distribution of opening diameters, with maximum concentrations at about 228.6 microns and at about 584.2 microns (see figure 23). The film (experiment No. 16) produced by a combination of a strip of holes of 127 microns and a strip of holes of 508 microns, has a hole diameter distribution that is concentrated primarily below 304.8 microns and has a slight concentration of holes with a diameter of about 584.2 microns (see Figure 24). These graphs indicate that the holes of 127 microns create primarily micro holes; that the holes of 508 microns create primarily larger holes, and that the combination of holes of 127 microns and 508 microns create a combination of micro holes and large holes. The comparable data is shown in Fig. 25, which teaches the distribution of aperture sizes in a film sample with openings having microholes and large holes, according to the invention, which was made in a commercial production line.

TABLE 6 PROPERTIES OF THE MOVIE CONTINUES WITH OPENINGS: TIME OF TRANSFER Experiment NO. Scraping time (traversing (seconds) 16.3 16 17.6 17 13.5 18 28.8 19 25.6 20 20.2 21 22.9 22 15.8 23 17.10 The data in Table 6 show that large diameter holes alone, or the combination of large diameter and small diameter holes (experiments 15, 16, 17, 22 and 23) produce a film with faster transfer or traverse times than films made with small diameter holes only (experiments 18-21).

TABLE 7 PROPERTIES OF THE MOVIE CONTINUES WITH OPENINGS: RIGIDITY OF THE MOVIE ExperimenLength of flexion Length of flexion to number. in DM (mm) in DT (mm) 22.8 6 16 26.3 6.5 17 22.3 6.5 18 27 6.3 19 26.8 5.5 20 26 9.5 21 25.5 8.5 22 23.5 5.8 23 27.30 8.0 Comparable commercial product 21.8 14.8 The data indicates that the machine direction bending length (DM) of the films of experiments 15-23, is comparable with that of other sanitary, commercial, plastic pad covers; and that the length of flexion in the transverse direction (DT) of the films is less than that of comparable commercial films. Accordingly, the expected stiffness and comfort of the films of the present invention are expected to be comparable to or superior to those of other films with commercial openings. The results of further experimentation are shown in Figure 26. In these experiments, the orifice spacing was varied to determine the effect on the open area of the film. Two water jet multiples were used in these experiments. The first, or multiple upstream, has a strip of holes with two rows of holes on respective sides of the longitudinal center line of the strip; the two rows of holes being deviated as shown in Figures 7B-7D; that is, the deviation distance was half the center-to-center separation within the row of holes. All holes had a diameter of 635 μm. The center-to-center separation of the holes for each experiment was varied as reported in Table 8. The second, or multiple downstream, had a strip of holes with a single row of holes in it. Each of the holes had a diameter of 127 microns and these holes were spaced at 508 μm, on a base from center to center. Water was supplied to the first manifold at 1054.5 kPa gauge. Water was supplied to the second manifold at 7030 kPa gauge. The film shifted to 45.72 m / min. The vacuum of the drum was 1524 mm of water. The following table 8 indicates the open area, the number of openings per square centimeter, the CDE and the air permeability for the films with resulting openings TABLE 8 Large Area Hole - No. of aberDCE, Penetrable-pelide, separates - open tures. μ? -dad to the air. - cion, μi. (*) 24 965.2 13.1 359.8 251.46 36.91 1270.0 12.0 447.2 215.9 34.79 26 1574.8 11.2 453.1 205.74 33.99 27 1905.0 10.1 511.4 182.88 31.79 * Two rows of holes of 635 microns in diameter. Air permeability was measured according to ASTM D737; the results are reported in table 8 in liters per second per square meter of film. The air permeabilities of the film with openings at 1054.5 kPa gauge and 45.72 m / minute were 22.66 1 / sec / m2 for the strip with holes of 635 microns diameter (only) of control (separation at 965.2 microns), which decreased almost linearly at 17.90 1 / sec / m2 for the 1905 micras separation. When the strip of 127 microns in diameter was added, the air permeability increased to 36.91 1 / sec / m2 for the control separation. There was an almost linear decrease with the separation to a value, at 31.79 1 / sec / m2 at 1905 microns. At 45.72 m / min, the combination of large diameter, control strip of 635 microns in diameter with the strip of 127 microns, provides around 14.25 1 / sec / m2 beyond the measured air permeability of the strip with holes large singlemonte. The above data indicates that, as the spacing of the large holes increases, fewer large holes are produced, and the open area is consequently reduced. The films with apertures made in accordance with US Patent Application Serial No. 08 / 417,404, and the films of the present invention, were tested and s made a comparison. The films were prepared in a continuous production line under the following conditions, shown in table 9.

TABLE 9 PREPARATION OF FILM WITH OPENINGS. AND PROPERTIES OF THE SAME Film made according to: Ho. series 08 / 417,404 Present invention Exxon EHB-631 Exxon EHB-631 precursor film Design of the sinusoidal cone (4,724 sinusoidal (4,724 udor rails / ») rails / ct) No. of hole strips 3 2 Pressure in strip of holes 11 (kPa lanoiétricos) 6,151.2 1,054.5 Pressure in strip of holes 12 (kPa lanoiétricos) 6,151.2 7,030.0 Pressure in strip of holes 13 (kPa lanoiétricos) 6,151.2 Hole ID a / a / a d / a TABLE 9 (continued) Tail hole (μi) 127/127/127 508/127 Water temperature 70 * C 71.1'C Linear velocity (i / iin) 45.72 45.72 Tratant surfactant Tween 20 Tween 20 Sanitary napkins were prepared comprising a cover, an absorbent center and a supporting sheet, using the films with openings in the frame 10 as covering materials. Two different towel designs were constructed and tested for transfer (traversing) and rewetting, using synthetic menstrual fluid. Synthetic menstrual fluid was prepared by dissolving 0.15% polyacrylamide in isotonic phosphate buffer. Approximately 0.3% Germaben was added to prevent bacterial development. The pH of the solution was measured at 7.4 and the viscosity at 30 centipoise at one radian per second. The results are shown in tables 11 and 12 below.

TABLE 10 TRANSFER AND REHUMPTION OF TOWELS MADE WITH FILMS WITH OPENINGS TOWEL DESIGN No. 1 Film made according to serial No. 08 / 417,404 Present invention Raspaso type for 5 cc (seconds) 68 62 ehutectation (g) 0.04 0.02 TABLE 11 TRANSFER AND REHUMECTATION OF TOWELS MADE WITH FILMS WITH OPENINGS TOWEL DESIGN No. 2 Film made according to serial No. 08 / 417,404 Present invention Transfer type for 5 cc (seconds) 39 39 Rehugement (g) 0.11 0.05 The data in Table 10 and Table 11 show the time of transfer (traverse) and absorption of rewet. The transfer time refers to the time elapsed for the absorption of 5 cc of synthetic menstrual fluid, a shorter time being convenient. The rewet absorption refers to the amount of fluid that can be absorbed in a filter paper that is placed in contact with a sanitary pad that has absorbed 5 cc of fluid in the transfer test, a smaller amount of rewetting being convenient. The data demonstrate that the larger open area and the larger aperture size of the films of the present invention result in handover times (pass through) at least equal to or faster than in the prior art films. However, even though the improved films of the present invention have larger open area and larger aperture sizes on average, than the prior art films, the towels made with the films of the present invention have unexpectedly lower rewet values, with with respect to the films of the prior art. Another test used to measure the rate of transport of menstrual fluid through the film with openings is the "drip test". The comparative data for the films of the present invention, against the films of the prior art, are shown in the following table 12.

TABLE 12 DRIP TEST DATA FOR MOVIES WITH OPENING IN THE TOWEL DESIGN No. 1 The data in Table 12 refer to the time required for the absorption of a drop of synthetic menstrual fluid, a shorter time being desirable. In the first test, the film was level. In the second test, the film was tilted at a 45 ° angle. The data further illustrates the superior fluid transport properties of the films of the present invention with respect to the films of the prior art. Plastic films with openings, according to the present invention, exhibit the following characteristics: softness to the touch; appearance and feel similar to those of a cloth; low film stiffness, as described in table 7; openings designs; open areas and scales of pore sizes as described in table 5 and figures 23-26; low base weight (< 23.73 g / m2); and film / air contact angles / synthetic menstrual fluid, on both sides of the film, of < 70 °.

The apertured film of the present invention, with the surfactant treatment, offers comparable fluid penetration rate, in general (when measured by the transfer times of 5 cc of synthetic menstrual fluid, a test method described in the application for patent pending serial No. 08 / 417,404), which is improved with respect to the films not treated with surfactant, by approximately 34%, either in a pulp-absorbent core construction or in a peat-based absorbent construction mossy

Claims

NOVELTY OF THE INVENTION CLAIMS

1. A method for forming a film with openings from a thermoplastic, stretchable polymeric material, characterized in that it comprises: a) providing a starting film comprising the stretchable thermoplastic polymeric material, having an upper surface and a lower surface; b) providing a supporting means comprising support regions located to support the starting film; depressed areas within which the film can be deformed by applying fluid forces; and means for allowing the applied fluid to be transported away from the support member; c) supporting the starting film on the supporting member, with portions of the lower surface of the film in contact with the supporting regions of the supporting member and with the upper surface of the film facing away from the supporting member; d) directing a fluid in the form of columnar streams from at least two series of holes, against the upper surface of the starting film, in a contact zone; the holes of the first series having a diameter greater than 254 microns and the fluid being supplied with a pressure less than 3515 kPa gauge, to cause the formation of large holes in the starting film; the holes of the second series having a diameter less than or equal to 254 microns, and the fluid being supplied with a pressure of at least 3515 kPa gauge, to cause the formation of microholes in the starting film; e) move the film from the contact area; and (f) removing the film now with openings from the support member.

2. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the holes of the first series have a diameter in the approximate range of 254 to 762 microns.

3. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the holes of the second series have a diameter in the approximate range of 25.4 microns to 254 microns.

4. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the holes of the first series have a diameter in the approximate range of 381 microns to 889 microns.

5. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the holes of the second series have a diameter in the approximate scale of 76.2 microns to 177.8 microns.

6. - A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the fluid emitted from the holes of the first series has a pressure in the approximate range of 703 to 3515 kPa gauge .

7. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the fluid emitted from the holes of the second series has a pressure in the approximate range of 3515 to 14060 kPa manometric.

8. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the fluid emitted from the holes of the first series has a pressure in the approximate range of 878.7 to 1406 kPa manometric.

9. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the fluid emitted from the second series of holes has a pressure in the scale of approximately 5.624 to 10.545 kPa manometric

10. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that it includes the additional step of providing a third series of holes; the third series of holes having a diameter greater than or equal to about 254 microns; having the fluid supplied with a pressure lower than 3515 kPa gauge.

11. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 10, further characterized in that the holes of the third series have a diameter in the approximate scale of 25.4 to 254 microns.

12. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 10, further characterized in that the holes of the third series have a diameter in the approximate scale of 76.2 to 177.8 microns.

13. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 10, further characterized in that the fluid supplied to the holes of the third series has a pressure in the approximate range of 3515 to 21.090 kPa rich manome.

14. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 10, further characterized in that the fluid emitted from the third series of holes has a pressure in the scale of approximately 5624 to 10,545 kPa manometric

15. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the microholes have an average DHE of around 24.4 to 177.8 microns.

16. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the microholes have an average DHE of around 50.8 to 127 microns.

17. A method for forming a film with openings from a stretchable thermoplastic material, in accordance with claim 1, further characterized in that the large-sized holes have a DUS of about 177.8 to 762 microns.

18. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the fluid from the first series of holes is directed against the upper surface of the starting film, before directing the fluid from the second series of holes.

19. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the microholes are defined by fibrils.

20. A method for forming a film with openings from a stretchable thermoplastic material, according to claim 1, further characterized in that the large-sized holes are defined by fibrils.

21. A film with openings, formed from a starting film of thermoplastic polymeric material, stretchable, and having a given thickness dimension, characterized in that it comprises: a plurality of openings extending through the thickness dimension of the movie; including the plurality of openings first and second groups of openings; and the openings of the first group have a size larger than the size of the openings of the second group; the openings of the first and second groups being defined by fibrils formed from the thermoplastic polymeric material.

22. A film with openings according to claim 21, further characterized in that the fibrils have an average length in the approximate range of 127 to 1270 microns.

23. A film with openings according to claim 21, further characterized in that the fibrils have an average width in the approximate range of 25.4 to 889 microns.

24. A film with openings according to claim 21, further characterized in that the fibrils have an average thickness in the approximate scale of 6.35 to 50.8 microns.

25. A film with openings in accordance with claim 21, further characterized in that the first group of openings comprises large size holes, having an average DHE of around 177.8 to 762 microns.

26. A film with openings according to claim 21, further characterized in that the first group of openings comprises large-sized holes, having an average DHE of 177.8 to 508 microns.

27. A film with openings in accordance with claim 21, further characterized in that the second group of openings comprises microholes having an average DHE of about 24.4 to 177.8 microns.

28. A film with openings according to claim 21, further characterized in that the second group of openings comprises microholes having a DHE of about 50.8 to 127 microns.

29. A film with openings according to claim 21, further characterized in that the starting film has a thickness in the approximate scale of 7.62 to 76.2 microns.

30. A film with openings according to claim 21, further characterized in that the overall thickness dimension of the thermoplastic polymer material is in the approximate range of 127 to 1016 microns.

31.- A film with openings according to claim 21, further characterized in that the apertured film has an overall thickness dimension greater than the given thickness dimension of the starting film.

32. - An absorbent product, characterized in that it comprises: an absorbent center having opposite oriented main surfaces and a film cover with openings, at least on one of said main surfaces; the apertured film having a side that makes contact with the body, facing outward, and an opposite side, oriented inward, towards the center; the film being formed with apertures of a starting film of thermoplastic polymeric material, and having a given thickness dimension; the apertured film having a plurality of apertures extending through the thickness dimension of the film; including the plurality of openings first and second groups of openings; and the openings of the first group have a size larger than the size of the openings of the second group; the openings of the first and second groups being defined by fibrils formed from the thermoplastic polymeric material.

33. An absorbent product according to claim 32, further characterized in that the fibrils have a length in the approximate range of 127 to 1270 microns.

34. An absorbent product according to claim 32, further characterized in that the fibrils have a width in the approximate range of 25.4 to 889 microns. 35.- An absorbent product according to claim 32, further characterized in that the fibrils have a thickness in the approximate scale of 6.

35 to 50.8 microns.

36.- An absorbent product according to claim 32, further characterized in that the first group of openings comprises holes of large size, having an average DHE of around 177.8 to 762 microns.

37. An absorbent product according to claim 32, further characterized in that the first group of openings comprises large size holes having an average DHE of about 177.8 microns to 508 microns.

38.- An absorbent product according to claim 32, further characterized in that the second group of openings comprises microholes having an average DHE of about 25.4 microns to 177.8 microns.

39. An absorbent product according to claim 32, further characterized in that the second group of openings comprises microholes having an average DHE of about 50.8 to 127 microns.

40.- An absorbent product according to claim 32, further characterized in that the apertured film has an overall thickness dimension greater than the given thickness dimension of the starting film.

41. An absorbent product according to claim 32, further characterized in that the film with openings is in direct contact with the at least one main surface of the absorbent center.

42. A method for forming a film with openings, from a stretchable thermoplastic polymeric material, characterized in that it comprises: a) providing a starting film comprising the stretchable thermoplastic polymer material and having an upper surface and a lower surface; b) providing a support member comprising support regions to support the starting film; depressed areas, within which the film can be deformed by applying fluid forces; and means for allowing the applied fluid to be transported away from the support member; c) supporting the starting film on the supporting member, leaving portions of the lower surface of the film in contact with the supporting regions of the supporting member, and with the upper surface of the film facing away from the supporting member; d) directing a fluid in the form of columnar streams, from a first series of holes, against the upper surface of the starting film, in a contact zone; having the holes a diameter greater than or equal to 254 microns; and the supplied fluid causes the formation of large holes in the starting film; e) move the film from the contact area; and f) removing the film now with openings from the support member.

43.- A method for forming a film with openings from a stretchable thermoplastic polymer material, according to claim 42, further characterized in that it includes the step of directing a fluid in the form of columnar streams, from a second series of holes , against the upper surface of the starting film, in a contact zone; the holes of the second series having a diameter less than or equal to 254 microns, and causing the fluid emitted therefrom, the formation of microholes in the starting film; the microholes being defined by fibrils of the thermoplastic material.

44. A method for forming a film with openings from a stretchable thermoplastic polymer material, according to claim 42, further characterized in that the large-sized holes have an average diameter in the approximate range of 177.8 to 508 microns.

45.- A method for forming a film with openings from a stretchable thermoplastic polymer material, according to claim 42, further characterized in that the pressure of the fluid supplied to those holes is in the approximate range of 703 to 3515 kPa gauge.

46.- A film with openings formed from a starting film of a thermoplastic polymeric material, stretchable, and having a given thickness dimension, characterized in that it comprises: a section of the stretchable thermoplastic polymer material having a dimension of overall thickness greater than the given thickness dimension of the starting film; a plurality of openings extending through the thickness dimension of the film; including the plurality of large-sized openings; the large-sized openings being defined by fibrils formed of said thermoplastic polymer material.

47.- A film with openings formed from a starting film of stretchable thermoplastic polymer material, according to claim 46, further characterized in that the plurality of openings includes microholes; the microholes being defined by fibrils formed from the thermoplastic polymer material.

48. A film with openings formed from a starting film of stretchable thermoplastic polymer material, according to claim 46, further characterized in that the large-sized holes have an average DHE of about 177.8 to 208 microns.

49.- A film with openings formed from a starting film of stretchable thermoplastic polymer material, according to claim 46, further characterized in that the fibrils have an average length in the approximate scale of 127 to 1270 microns; they have an average width in the approximate range of 25.4 micras to 889 micras; and they have an average thickness in the approximate scale of 6.35 microns to 50.8 microns.

50. An absorbent product characterized in that it incorporates the apertured film of claim 46, which includes an absorbent center having opposingly oriented major surfaces; the film with openings covering at least one of said major surfaces.

51.- A method for forming a film with openings from a thermoplastic, stretchable polymeric material, characterized in that it comprises: a) providing an enhanced starting film, comprising the stretchable thermoplastic polymer material, having an upper surface and a surface lower; b) providing a support member comprising support regions located to support the starting film; depressed areas within which the film can be deformed by applying fluid forces; and means for allowing the applied fluid to be transported away from the support member; c) supporting the starting film in the supporting member, with portions of the lower surface of the film in contact with the supporting regions of the supporting member, and with the upper surface of the film facing away from the supporting member; d) directing a fluid in the form of columnar streams, from at least two series of orifices, against the upper surface of the starting film, in a contact zone; the holes of the first series having a diameter greater than 254 microns, and the fluid being supplied with a pressure lower than 3515 kPa gauge, to cause the formation of large holes in the starting film; the holes of the second series having a diameter less than or equal to 254 microns, and the fluid supplied to them having a pressure of at least 3515 kPa gauge, to cause the formation of microholes in the starting film; e) move the film from the contact area; and f) removing the film, now with openings, from the support member.

52. A method for forming a film with openings according to claim 51, further characterized in that it includes providing the starting film enhanced with treatment with corona discharge on one of its sides.

53. A method for forming a film with openings according to claim 51, further characterized in that it includes applying a surfactant to one side of the film with openings.