Surgery – Means and methods for collecting body fluids or waste material – Absorbent pad for external or internal application and...
Reexamination Certificate
2001-10-30
2003-08-12
Vanatta, A. (Department: 3761)
Surgery
Means and methods for collecting body fluids or waste material
Absorbent pad for external or internal application and...
C604S359000, C604S367000, C604S368000, C604S378000, C604S385010, C604S385230
Reexamination Certificate
active
06605752
ABSTRACT:
TECHNICAL FIELD
An absorbent product which possesses two longitudinal side edges, two transverse end edges, a longitudinal centre line and a transverse centre line, and which comprises a liquid-permeable outer layer, a liquid-impermeable backing layer and an absorption core which is located between the said outer layer and the said backing layer, with the said absorption core comprising a first and a second absorption layer, with the first absorption layer being arranged behind the liquid-permeable outer layer and the second absorptive layer being arranged between the first absorption layer and the liquid-impermeable backing layer, with the first absorption layer having two longitudinal channels, with each of the channels having an outer edge closest to the corresponding longitudinal side edge of the product and an inner edge closest to the longitudinal centre line of the product.
BACKGROUND
A problem with absorbent products is that of ensuring that they do not leak. Leakage is not usually due to the total absorptive capacity of the product being insufficient. Instead, the reason for the leakage can, for example, be that released liquid ends up outside the absorption body due to the product having come to be located in an incorrect position when being put on or as a consequence of stresses during use, or that the product has been deformed such that the surface available for liquid absorption has become insufficient. Another common reason for leakage is that the liquid runs along the surface of the product without being absorbed due to the product exhibiting low instantaneous liquid absorption or having been deformed in an undesirable manner when being used.
It has been previously known, from U.S. Pat. No. 4,655,759, to provide an absorbent product with compressed, arcuated channels which are arranged in the longitudinal direction of the absorption core. The compressed channels are stated to assist the article in forming the shape of a W in cross-sectional profile when the article is pressed together by the thighs of the user. The improved fit is said to minimize the risk of leakage. Beyond the compressed channels, in the direction towards the rearside, i.e. in that part of the product which is arranged, during use, closest to the back and the caudal vertebra, the cross-sectional profile is changed to an inverted V shape. This is said to make it possible to achieve a better fit between the buttocks of the user.
WO 95/15139 attempts to solve the problem of lateral leakage by means of compressed channels which shape the absorbent article into a container for the liquid when the article is used. In addition, the channels help the article to distance itself somewhat from the user. WO 90/14814 uses sewn or glued channels in order to obtain an effect of upturned edges which is said to protect against lateral leakage. EP 0,249,405 uses compressed, arcuate longitudinal channels on each side of an elevation on the core. In addition, the channels can extend further to compressed areas or be arranged around the whole of the core. This is stated to ensure that full contact is achieved between the user and the article and to prevent lateral leakage.
However, the abovementioned inventions fail to identify and indicate a satisfactory way in which all possibilities of leakage can be avoided.
An aim of the present invention is to improve existing efforts to solve the above problem. Another aim of the present invention is to improve instantaneous liquid absorption at the same time as obtaining a good, stable and user-friendly fit and thereby to decrease discomfort, leakage and skin irritations which can arise due to the product chafing the skin.
ACCOUNT OF THE INVENTION
The present invention has been used to achieve an absorbent product of the type mentioned at the outset, which product essentially eliminates the problems associated with previously known products of this nature.
The product which is designed in accordance with the invention is principally distinguished by the fact that the two longitudinal channels extend through the whole of the thickness of the first absorptive layer and that a compressed area is arranged between the longitudinal sides of the absorbent product and that the distance between the side edges of the compressed area is smaller than or equal to the distance between the outer side edges of the longitudinal channels.
The combination of the longitudinal channels and the compressed area between the channels results in high instantaneous liquid absorption, with a good fit at the same time being retained during the dry state. The liquid which the product receives can penetrate rapidly and readily down through the channels to the underlying core, resulting in more rapid admission. The channels also shape the product in conformance with the inside of the user's thighs, resulting in a good U-like fit being achieved. A good fit minimizes leakage which can occur due to occasional gaps which are formed between the absorbent product and the user's body. The compressed area contributes to ensuring a good fit and increases the stability and deformation resistance of the product, thereby helping the absorbent product to remain in place during use. In addition, the second absorptive layer serves to hide the channels so that the latter cannot be seen through the liquid-impermeable backing layer, something which might otherwise be regarded by users as being disturbing and disquieting. A particularly good masking effect is obtained if the compressed area is arranged in the second absorptive layer. A further advantage of the invention is also the fact that substantial economies in material can be obtained due to it being possible to recirculate all the material which has been removed from the channels back to earlier production stages.
The compressed area preferably extends transversely the whole way between the outer edges of the two channels. In addition, the longitudinal extent of the compressed area preferably corresponds essentially to the length of the channels. Alternatively, the length of the compressed area can be greater or less than the length of the channels; for example, the compressed area can extend the whole length of the absorptive body. It is also possible to design the compressed area with straight side edges even if the channels have a curved shape, or vice versa. Moreover, if the compressed area extends past the ends of the channels, the portion or portions of the compressed area being located beyond the channels may have a greater width than the distance between the outer edges of the channels. This situation can occur, for instance, when the channels are curved and the compressed area has curved longitudinal edges which follows the contour of the channels and extend in a curved fashion beyond the ends of the channels. However, preference is given to designing the side edges of the compressed area such that they the have the same general shape as the channels.
According to an alternative embodiment, it is possible to arrange a further two longitudinal arcuate channels in the second absorption layer, with the channels extending through the whole of the thickness of the second absorption layer. The masking effect of the second absorption layer is naturally lost in such an embodiment.
According to one embodiment, the first absorption layer consists of chemical thermomechanical pulp and the second absorption layer consists chemical pulp. Chemical thermomechanical pulp will henceforth be termed CTMP and chemical pulp will henceforth be termed CP. A CTMP layer has a relatively open structure with relatively large capillaries since CTMP fibres are rigid and moderately coarse. To a large extent, the open structure remains even after wetting since the fibres retain much of their rigidity. Consequently, an absorption layer composed of CTMP has a comparatively great ability to take up liquid instantaneously and good ability to retain liquid but a comparatively poor ability to spread liquid.
CP fibres are thin and flexible and form a fibre structure having relatively
Magnusson Ing-Britt
Nilsson Lennart
Grayson Angela J
SCA Hygiene Products AB
Vanatta A.
LandOfFree
Absorbent product with improved instantaneous liquid... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Absorbent product with improved instantaneous liquid..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Absorbent product with improved instantaneous liquid... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3122454