Surgery – Means and methods for collecting body fluids or waste material – Absorbent pad for external or internal application and...
Patent
1994-11-18
1997-10-07
Jones, Mary Beth
Surgery
Means and methods for collecting body fluids or waste material
Absorbent pad for external or internal application and...
604358, 604378, 264504, 264DIG70, 428131, 428138, A61F 1315, B32B 310, B29C 4322
Patent
active
056742118
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for manufacturing a material which is suitable for use as the top sheet of an absorbent disposable article, such as a sanitary napkin, an incontinence guard or a diaper, and also to material manufactured in accordance with the method.
2. Description of Related Art
Absorbent disposable articles are often provided with a top sheet on the side of the article which lies proximal to the wearer in use. Consequently, the top sheet should be felt to be soft and dry by the wearer. In order to provide a feeling of dryness to the wearer, perforated hydrophobic plastic films are sometimes used closest to the wearer's body. It is also known to provide in the film holes of a conical or straight tubular configuration, so as to obtain capillaries which reduce the risk of re-wetting, i.e. to reduce the tendency of fluid that has been absorbed in an underlying absorbent body flowing back through the perforations in the plastic film when the absorbent body is subjected to external pressure forces. Another known method of alleviating risk of re-wetting involves providing a spacing sheet between the plastic sheet and the absorbent body and by forming the top sheet from several different layers of material.
One example of a composite top sheet is comprised of a perforated plastic film which has been laminated to a layer of non-woven material by hot-calendaring, ultrasonic welding or gluing. Such top sheets have good draining ability and relatively low re-wetting tendencies, but are relatively stiff and often even rough.
OBJECTS AND SUMMARY
An object of the present invention is to provide top sheet material which in addition to possessing good drainage, re-wetting and liquid dispersion properties is also soft and smooth.
This object is achieved in accordance with the invention with a method of the kind defined in the introduction which is characterized in that a laminate comprising a plastic film and a layer of non-woven material on at least one side of the plastic film is applied to a perforated supportive device with the non-woven layer or one of the non-woven layers of the laminate facing towards said device; in that the plastic film is heated to a temperature above its softening temperature; and in that there is generated between the two mutually opposing sides of the laminate a pressure difference of such magnitude as to cause the plastic film to rupture in the regions of the perforations in the supportive device, so as to form openings which lead to the associated non-woven layer or layers. By forming the perforations in the plastic film subsequent to having laminated the film with the non-woven layer or layers, it is possible to chose other laminating methods, such as extrusion coating of the non-woven material with plastic film, than the method of laminating a pre-perforated plastic film with a layer of non-woven material, therewith enabling a softer top sheet material to be produced. In addition to simplifying the laminating method, the invention also simplifies the perforating method, since the pieces of film which break away from the plastic film seat firmly in the non-woven material, thereby obviating the need to handle waste or to clean the perforated supportive device when practicing the inventive method.
The invention also relates to top sheet material manufactured in accordance with the method, this material being characterized in that the non-woven material on one side of the plastic film includes depressions or hollows which are located beneath the holes in the plastic film and the bottom surfaces of which are covered with material that has broken away from the plastic film. Because the bottom surfaces of the depressions or hollows are covered at least over larger parts thereof with a fluid-impervious material, liquid or fluid discharged by the wearer will spread laterally in the non-woven material. The top sheet also becomes more attractive from an aesthetic point of view, since the film material present in the
REFERENCES:
patent: 4041949 (1977-08-01), Kozak
patent: 4495133 (1985-01-01), Sugihara et al.
patent: 4704112 (1987-11-01), Suzuki et al.
patent: 4726976 (1988-02-01), Karami et al.
patent: 4781962 (1988-11-01), Zamarripa et al.
patent: 4995930 (1991-02-01), Merz et al.
Jones Mary Beth
Molnlycke AB
Ruhl Dennis
LandOfFree
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