Fabric (woven – knitted – or nonwoven textile or cloth – etc.) – Coated or impregnated woven – knit – or nonwoven fabric which... – Coated or impregnated natural fiber fabric
Reexamination Certificate
1998-09-24
2001-11-20
Morris, Terrel (Department: 1771)
Fabric (woven, knitted, or nonwoven textile or cloth, etc.)
Coated or impregnated woven, knit, or nonwoven fabric which...
Coated or impregnated natural fiber fabric
Reexamination Certificate
active
06319863
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a water-disintegratable fibrous sheet that is easily dispersed by flushing water, and more particularly, relates to a water-disintegratable fibrous sheet that is excellent in water-disintegratability, strength, heat-resistance and water-disintegratability in cold water.
2. Description of the Prior Art
Fibrous sheets are used to cleanse human skin, e.g., skin around anus, and to clean a toilet room. The fibrous sheet is preferably water-disintegratable to be thrown away and drained in a toilet as it is. If it is not excellent in water-disintegratability, it requires a long time to be dispersed in a septic tank, and brings danger of clogging drainpipes of a toilet, when being thrown away and drained in a toilet. However, in general, a packed fibrous sheet impregnated with a cleansing liquid or the like has to be strong enough to endure conducting wiping operations while being impregnated with a cleansing liquid, and at the same time, has to keep its water-disintegratability in the event of being thrown away and drained in a toilet. Therefore, a water-disintegratable fibrous sheet that has good water-disintegratability and strength sufficient to use is demanded.
Japanese Laid-Open Patent H3-292924 discloses a water-disintegratable cleaning product composed of fibers containing polyvinyl alcohol impregnated with an aqueous solution of boric acid. Japanese Laid-Open Patent H6-198778 discloses a water-disintegratable sanitary napkin composed of non-woven fabric containing polyvinyl alcohol added with boric ion and bicarbonic ion. In these inventions, fibrous sheets are produced by binding each fiber using properties such that boric acid cross-links polyvinyl alcohol. However, a large amount of binder, i.e., polyvinyl alcohol, is required to produce fibrous sheets having strength sufficient to use.
Furthermore, miscellaneous products, including such water-disintegratable products, are often left in a vehicle or a warehouse during their transportation and storage, and the temperatures in such a closed space rise above the outer atmospheric temperature. In the case where they are stored in a house, they may be possibly left under a temperature of 40° C. or higher in the middle of summer. When water-disintegratable fibrous sheets which are previously impregnated are packed as finished products and then shipped to market, water-disintegratability and strength of the fibrous sheets are remarkably deteriorated if they are left under high temperature circumstances. Therefore, a water-disintegratable fibrous sheet has to retain its water-disintegratability and strength even under high temperature circumstances, that is, its heat-resistance is important. However, there is no report relating to the heat-resistance in the water-disintegratable cleaning products and the water-disintegratable non-woven fabric disclosed in the preceding publications.
Water temperatures are generally lower than the atmospheric temperature though they vary depending on seasons. When a fibrous sheet is thrown away and drained in a toilet after used, it has to be disintegrated in water at a temperature lower than the atmospheric temperature, i.e., in cold water. However, as to the fibrous sheet using polyvinyl alcohol as a binder, its water-disintegratability is generally enhanced in response to a rise in temperatures of water, but deteriorated in response to a fall in temperatures of water.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a fibrous sheet having good water-disintegratability and sufficient strength to withstand practical use.
Another object of the present invention is to provide a water-disintegratable fibrous sheet that is excellent in heat-resistance.
Still another object of the present invention is to provide a water-disintegratable fibrous sheet that is excellent in water-disintegratability even in cold water.
The present inventors have found that a water-disintegratable fibrous sheet using a modified polyvinyl alcohol is excellent in water-disintegratability, strength, heat-resistance and water-disintegratability in cold water.
The present invention is to provide a water-disintegratable fibrous sheet comprising water-dispersible fibers, which sheet contains at least one binder selected from the group consisting of a sulfonic acid-modified polyvinyl alcohol and a carboxylic acid-modified polyvinyl alcohol, and at least one compound selected from the group consisting of a water-soluble organic salt, a water-soluble inorganic salt and a boron compound being incorporated in the sheet.
In the fibrous sheet using these modified polyvinyl alcohols, sufficient strength to withstand practical use such as wiping operation can be maintained even in a wet state, for example, in a state of impregnating a cleaning liquid drug therein. Further, when it is exposed to a large amount of water, the fibers of the fibrous sheet are dispersed in water, so that water-disintegratability is exhibited.
REFERENCES:
patent: 3438808 (1969-04-01), Hawkins et al.
patent: 3692725 (1972-09-01), Duchane
patent: 4172930 (1979-10-01), Kajitani et al.
patent: 4245744 (1981-01-01), Daniels et al.
patent: 4258849 (1981-03-01), Miller
patent: 4537807 (1985-08-01), Chan et al.
patent: 5252332 (1993-10-01), Goldstein
patent: 5387638 (1995-02-01), Nakamae et al.
patent: 5972805 (1999-10-01), Pomplun et al.
patent: 5986004 (1999-11-01), Pomplun et al.
patent: H3-292924 A (1991-12-01), None
patent: H6-198778 A (1994-07-01), None
Konishi Takayoshi
Takeuchi Naohito
Koda & Androlia
Morris Terrel
Torres Norca L.
Uni-Charm Corporation
LandOfFree
Water-disintegratable fibrous sheet containing modified... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Water-disintegratable fibrous sheet containing modified..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Water-disintegratable fibrous sheet containing modified... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2608388