Stock material or miscellaneous articles – Structurally defined web or sheet – Including grain – strips – or filamentary elements in...
Patent
1993-07-01
1995-03-21
Nakarani, D. S.
Stock material or miscellaneous articles
Structurally defined web or sheet
Including grain, strips, or filamentary elements in...
428107, 428131, 428134, 428163, 428167, 428226, 428247, 428255, 428910, D03D 1500
Patent
active
053994116
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a flexible, air-permeable plastic sheet having an appearance like woven fabric.
BACKGROUND OF THE INVENTION
It is well known to provide a flexible thermoplastic sheet inclusive of plastic film with a plurality of fine pores and thereby to make the sheet air-permeable. The porous plastic sheet formed in this manner usually has slimy gloss and sticky touch characterizing the plastic sheet which are disliked by users in some applications of the sheet. To alleviate such gloss and to improve the touch of the sheet, several techniques have already been proposed, for example, the technique by which the sheet surface is embossed to take the gloss off and simultaneously to provide the surface with irregularities and pores, and the technique by which a third ingredient having delustering effect as well as pore forming effect is previously mixed into raw material for the sheet so that desired delustering and pore forming effects may be achieved on a step of sheet production.
However, these well known techniques have not been able to achieve a satisfactory improvement of the plastic sheet particularly for such plastic sheet used as a topsheet of disposable hygienic wearable articles such as a sanitary napkin and a disposable diaper, because said gloss and touch of the topsheet of such hygienic wearable articles, which are destined to be in direct contact with wearer's skin, are decisively disliked. U.S. Pat. No. 4,342,314 discloses a technique to provide a flexible plastic sheet with a fibrous appearance and capillary structure. This technique also intends to alleviate the sticky touch usually characterizing the plastic sheet, but the sheet obtained by this technique is considered to have a smooth surface and rather slimy gloss because of its smoothness.
Accordingly, it is a principal object of the present invention to alleviate said gloss and undesirable touch conventionally characterizing the plastic sheet by providing the plastic sheet with air-permeable vacant spaces defined by ribs crossing one another so that these ribs and vacant spaces may cooperate together to create an appearance like woven fabric.
DISCLOSURE OF THE INVENTION
The object set forth above is achieved, according to the present invention, by flexible, air-permeable plastic sheet having an appearance like woven fabric, said plastic sheet comprising: side edges curved downward and a plurality of ribs extending in a second direction, each having opposite side edges curved downward so that these first and second direction ribs cross one another to present said appearance like woven fabric; said second direction ribs crossing these first direction ribs defining together an air-permeable vacant space; and crossings which are adjacent and diagonally opposed to each other so that bulgings aligned in the first direction are formed and a pair of lower edges of each said bulging are connected to tops of said pair of second direction ribs, on one hand, and said pair of second direction ribs bulge upward at third and fourth crossings which are adjacent and diagonally opposed to each other so that bulgings aligned in the second direction are formed and a pair of lower edges of each said bulging are connected to tops of said pair of first direction ribs, on the other hand.
According to an aspect of the invention, each of said first and second direction ribs preferably has a hollow arcuate cross-section.
According to another aspect of the invention, each said second direction rib has preferably a width smaller than a width of each said first direction rib at least along a longitudinally intermediate portion of said second direction rib.
According to still another aspect of the invention, said pair of adjacent fist direction ribs are preferably provided with bridges connecting opposite lower edges of these ribs.
Advantageous effect provided by the invention will be readily apparent from the following description.
In the plastic sheet of the invention constructed as has been mentioned above,
REFERENCES:
patent: 2902037 (1959-09-01), Harwood
patent: 4342314 (1982-08-01), Radel et al.
patent: 4601868 (1986-07-01), Radel
patent: 4609518 (1986-09-01), Curro et al.
patent: 4710185 (1987-12-01), Sneyd, Jr. et al.
Murakami Masaki
Suzuki Migaku
Yamamoto Masamitsu
Nakarani D. S.
Uni-Charm Corporation
LandOfFree
Flexible, air-permeable plastic sheet does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Flexible, air-permeable plastic sheet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flexible, air-permeable plastic sheet will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1147845