The present invention relates generally to disposable absorbent articles. More specifically, the invention relates to disposable diapers with optimal means for preventing leakage of body exudates.
In a disposable diaper, an absorbent core placed between a top sheet and a back sheet is used for absorbing body exudates. Typically, fluff pulp has been used as main material for the absorbent core. In order to improve the absorbability of the absorbent core, various measures have been employed such as mixing highly absorptive polymer particles in the pulp. However, the absorbing rates of the absorbent core are not adequately high to absorb a large quantity of body exudates at once, i.e. as soon as the body exudates are excreted onto the upper surfaces of the top sheet and the absorbent core. As a result, the exudates, at least partially, flow onto the upper surface of the topsheet laterally, and often leak out along the side edges of the diaper. Such leakage readily occurs when the quantity of exudates is large.
In order to prevent leakage of exudates from the disposable diaper, leakage protecting baffles or cuffs are provided along the side edges of the diaper. These cuffs conform the side regions of the diaper to the wearer's body thereby preventing exudates from passing out of the diaper. However, diapers with such cuffs have numerous disadvantages. Body exudates may leak out from gaps formed between the cuffs and a wearer's body, for example, when the wearer assumes a certain posture. Moreover, the exudates get accumulated at the cuffs, thereby frequently damaging the cuffs.
U.S. Pat. No. 4,579,556 discloses a disposable diaper in which the opposite side edges of the absorbent core are covered with part of an impervious back sheet, and thereby a certain degree of a leakage protective effect is achieved. However, there is a possibility of excreted material leaking out when the side edges are subjected to body pressure.
U.S. Pat. No. 4,892,528 discloses a disposable diaper in which two sheets resistant to the passage of water are disposed adjacent to and partially outwardly from two side surfaces of the absorbent core. The two sheets along with the back sheet are used to provide leakage-protecting baffles, which extend above the top surface of the absorbent core. In this design, there is a risk of exudates leaking out once such extended baffles twist due to body movement.
U.S. Pat. No. 5,167,653 discloses a disposable garment provided with a plurality of flaps extending along laterally opposite sides of the garment and normally biased by their own elastic shrinking potential to turn upward. This invention makes the disposable garment difficult to wear because of multiple flaps containing elastic members.
In light of the above described disadvantages, there is a need for a disposable diaper that is simple in design and provides effective prevention of leakage of body exudates. Additionally, the disposable diaper should be easy-to-wear and should prevent exudates from leaking out irrespective of body movements or posture of the person wearing the article.
The present invention improves the mechanism of blocking leakage of body exudates from a diaper by providing a unitized double cuff structure along side edges of the diaper.
In one embodiment, the disposable absorbent article provided by the invention comprises a liquid permeable top sheet, a liquid impermeable back sheet, an absorbent core interposed between the top sheet and the back sheet, and a pair of unitized double cuffs located outwardly with respect to the absorbent core along laterally opposite sides thereof.
Each cuff comprises a ribbon wherein a first portion of the ribbon is bonded to the top sheet at a predefined distance from a second portion of the ribbon thereby forming an inverted “V” structure between the attached portions. A further portion of the ribbon or fringe extension, extends upwardly beyond one of the bonds formed between the ribbon and the top sheet.
The unitized double cuff extends lengthwise all along side edges of the diaper. One or more elastic bands may be provided within the ribbon in lengthwise direction.
The above described unitized double cuff conforms tightly to a wearer's body and blocks exudates from leaking out of the diaper irrespective of the quantity of the exudates or the body posture of the wearer.
These and other features and advantages of the present invention will be appreciated, as they become better understood by reference to the following Detailed Description when considered in connection with the accompanying drawings:
In the foregoing specification, specific embodiments of the present invention have been described. However, one of ordinary skill in the art will appreciate that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present invention. The benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of any or all the claims.
With reference to the drawings, a new design for a disposable absorbent article is described with the principles and embodiments as set out below. The new design provides a unitized double cuff in the disposable absorbent article for preventing the leakage of body exudates from the disposable absorbent article such as a diaper.
Top sheet 101 is preferably maintained by fibres entangled together in a configuration of a nonwoven fabric.
Preferably, absorbent retaining layer 202 may be made of fluff pulp, fibrous web, or nonwoven fabric. In order to improve the absorbability of absorbent retaining layer 202, embossing and mixing of highly absorptive polymer particles is done. Isolating layer 203 is in the form of a fibrous web having a relatively low density so as to define a large vacant space therein and exhibits a high compressive elasticity recovery rate under wet conditions.
Ribbon 301 is made of liquid impervious material such as polypropylene nonwoven. First and second bonds 302 and 303 may be manufactured using ultrasonic bonding or hot melt adhesives, which are a mixture of resins, oils, and tackifiers. The hot melt adhesive is applied, melted, and upon cooling, provides a bonding force to glue ribbon 301 to top sheet 304. Elastic bands may be provided within the inverted “V” structure lengthwise along the ribbon as well as within the fringe extension.
Having described the invention, it is readily apparent that various changes and modifications can be made to the above constructions without departing from the scope of the invention. Therefore, it is intended that all the matter contained in the above description should be interpreted as illustrative and not in a limiting sense. Moreover, the present invention can be used in other contexts, such as in other garments to retain exudates.