EP0003186A1 - Moist packaged towelette and method of making same - Google Patents
Moist packaged towelette and method of making same Download PDFInfo
- Publication number
- EP0003186A1 EP0003186A1 EP79300077A EP79300077A EP0003186A1 EP 0003186 A1 EP0003186 A1 EP 0003186A1 EP 79300077 A EP79300077 A EP 79300077A EP 79300077 A EP79300077 A EP 79300077A EP 0003186 A1 EP0003186 A1 EP 0003186A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- aqueous solution
- polyvinyl alcohol
- binder
- towelette
- boric acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000004519 manufacturing process Methods 0.000 title description 3
- 229920002451 polyvinyl alcohol Polymers 0.000 claims abstract description 54
- 239000004372 Polyvinyl alcohol Substances 0.000 claims abstract description 50
- 239000007864 aqueous solution Substances 0.000 claims abstract description 50
- 239000011230 binding agent Substances 0.000 claims abstract description 38
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims abstract description 38
- 239000004327 boric acid Substances 0.000 claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 37
- 150000001875 compounds Chemical class 0.000 claims abstract description 22
- 239000004745 nonwoven fabric Substances 0.000 claims abstract description 20
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims abstract description 16
- 229920002689 polyvinyl acetate Polymers 0.000 claims abstract description 12
- 239000011118 polyvinyl acetate Substances 0.000 claims abstract description 12
- 229910052938 sodium sulfate Inorganic materials 0.000 claims abstract description 8
- 235000011152 sodium sulphate Nutrition 0.000 claims abstract description 8
- 229920001038 ethylene copolymer Polymers 0.000 claims abstract description 7
- HDERJYVLTPVNRI-UHFFFAOYSA-N ethene;ethenyl acetate Chemical group C=C.CC(=O)OC=C HDERJYVLTPVNRI-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000000243 solution Substances 0.000 claims description 22
- 150000003839 salts Chemical class 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 4
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 claims description 2
- 238000004806 packaging method and process Methods 0.000 claims description 2
- 238000009736 wetting Methods 0.000 claims description 2
- DQXBYHZEEUGOBF-UHFFFAOYSA-N but-3-enoic acid;ethene Chemical group C=C.OC(=O)CC=C DQXBYHZEEUGOBF-UHFFFAOYSA-N 0.000 claims 1
- 239000000203 mixture Substances 0.000 abstract description 7
- 239000000839 emulsion Substances 0.000 description 12
- IMROMDMJAWUWLK-UHFFFAOYSA-N Ethenol Chemical compound OC=C IMROMDMJAWUWLK-UHFFFAOYSA-N 0.000 description 11
- 238000007654 immersion Methods 0.000 description 8
- 239000004744 fabric Substances 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000000717 retained effect Effects 0.000 description 3
- 230000007928 solubilization Effects 0.000 description 3
- 238000005063 solubilization Methods 0.000 description 3
- VZCYOOQTPOCHFL-OWOJBTEDSA-N Fumaric acid Chemical compound OC(=O)\C=C\C(O)=O VZCYOOQTPOCHFL-OWOJBTEDSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- PXRKCOCTEMYUEG-UHFFFAOYSA-N 5-aminoisoindole-1,3-dione Chemical compound NC1=CC=C2C(=O)NC(=O)C2=C1 PXRKCOCTEMYUEG-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 230000002745 absorbent Effects 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Substances OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000002781 deodorant agent Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000001530 fumaric acid Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 239000002304 perfume Substances 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 239000001508 potassium citrate Substances 0.000 description 1
- 229960002635 potassium citrate Drugs 0.000 description 1
- QEEAPRPFLLJWCF-UHFFFAOYSA-K potassium citrate (anhydrous) Chemical compound [K+].[K+].[K+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O QEEAPRPFLLJWCF-UHFFFAOYSA-K 0.000 description 1
- 235000011082 potassium citrates Nutrition 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000004627 regenerated cellulose Substances 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- -1 sodium sulphate Chemical class 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- VZCYOOQTPOCHFL-UHFFFAOYSA-N trans-butenedioic acid Natural products OC(=O)C=CC(O)=O VZCYOOQTPOCHFL-UHFFFAOYSA-N 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
- D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
- D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
- D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
- D04H1/58—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives
- D04H1/64—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives the bonding agent being applied in wet state, e.g. chemical agents in dispersions or solutions
-
- D—TEXTILES; PAPER
- D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
- D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
- D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
- D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
- D04H1/58—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives
- D04H1/587—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives characterised by the bonding agents used
Definitions
- This invention relates to a moist packaged towelette and to a method of making the same.
- Moist packaged towelettes are generally made by coating a sheet of nonwoven fabric, usually absorbent paper, with a binder and storing the coated fabric in contact with an aqueous solution in a container.
- the aqueous solution typically contains alcohol and, for example, a perfume or deodorant.
- the binder increases the structural integrity of the nonwoven fabric and prevents it disintegrating in the aqueous solution.
- nonwoven fabric as used herein includes fabrics comprising carded or randomly orientated or cross-laid fibres.
- the fibres may comprise, for example, natural or regenerated cellulose, other synthetic or proteinaceous fibres of biodegrade materials, or mixtures of these).
- binder for nonwoven fabrics which are not intended to be exposed to moisture is polyvinyl alcohol. Whilst nonwoven fabrics provided with this binder have excellent structural integrity in the dry they disintegrate rapidly when immersed in water.
- a nonwoven fabric provided with a binder comprising polyvinyl alcohol will retain a high structural integrity in contact with an aqueous solution provided that the aqueous solution contains a sufficient concentration of a compound to prevent the polyvinyl alcohol dissolving in the aqueous solution.
- the polyvinyl alcohol dissolves thereby weakening the structural integrity of the towelette.
- the present invention provides a moist packaged towelette comprising a sheet of nonwoven fabric provided with a binder and maintained in contact with an aqueous solution in a container characterized in that said binder is polyvinyl alcohol and said aqueous solution contains a compound which is present in said solution at a sufficient concentration to prevent said polyvinyl alcohol dissolving in said aqueous solution but which, when diluted in excess water, permits said polyvinyl alcohol to dissolve in said excess water thereby reducing the structural integrity of said towelette.
- boric acid is presently preferred and preferably comprises at least 1% (by weight) of the aqueous solution with 3% to 5% (by weight) being preferred and 4% to 5% (by weight) being more preferred.
- the required concentration in the aqueous solution is so high that, in many cases, the salt crystalizes on the skin when the towelette is used.
- the salts which are used should be those which need be present to no more than 40% (by weight) of the aqueous solution and, more preferably, to no more than 20% (by weight) of the aqueous solution.
- sodium sulphate at a concentration of between 3% and 20% (by weight) of the aqueous solution and more preferably between 7% and 20% (by weight) of the aqueous solution.
- Polyvinyl alcohol is generally produced by the hydrolysis of polyvinyl acetate. Pure polyvinyl alcohol (i.e. 100% hydrolysed polyvinyl acetate) is relatively insoluble in water at room temperature when compared with 80% to 99% hydrolysed polyvinyl acetate. Accordingly, the binder preferably comprises a mixture of polyvinyl alcohol and polyvinyl acetate. If desired the polyvinyl alcohol may comprise as little as 1% (by weight) of such a mixture although it preferably comprises between 80% and 95% thereof.
- Mixtures comprising vinyl acetate-ethylene copolymers and polyvinyl alcohol may also be used as a binder.
- the polyvinyl alcohol preferably comprises from 1% to 10% (by weight) of the binder and probably acts as a protective colloid.
- the binder may also contain polyvinyl acetate and preferably between 5 and 25% .(by weight) thereof.
- One particularly preferred range of binders comprises (by weight) 1 to 10% of 80 - 90% hydrolysed polyvinyl acetate and the balance vinyl acetate-ethylene copolymers.
- the vinyl acetate-ethylene copolymers contain (by weight) not more than 45% vinyl acetate and not more than 60% ethylene.
- the weight of the binder is preferably between 5% and 50% of the weight of the untreated nonwoven fabric.
- the present invention also provides a method for making a moist packaged towelette which method comprises the step of wetting a sheet of nonwoven fabric provided with a binder by bringing said sheet into contact with an aqueous solution characterized in that said binder comprises polyvinyl alcohol and said aqueous solution contains a sufficient concentration of a compound which prevents the polyvinyl alcohol dissolving in the aqueous solution but which, when dissolved in excess water, allows the polyvinyl alcohol to dissolve in the water thereby reducing the structural integrity of the towelette.
- the present invention also provides a method for making a moist packaged towelette which method comprises taking a sheet of nonwoven fabric which has been provided with a binder and packaging said sheet of treated material in contact with an aqueous solution in a container characterized in that said binder comprises polyvinyl alcohol and said aqueous solution contains a sufficient concentration of a compound which prevents the binder from dissolving in the aqueous solution but which, when dissolved in excess water, allows the binder to dissolve in the water thereby reducing the structural integrity of the towelette.
- said compound is boric acid and advantageously said aqueous solution comprises at least 1% (by weight) of said compound with 3% to 5% (by weight) being preferred and 4% to 5% (by weight) being more preferred.
- the container should preferably be impermeable to all the components of the aqueous solution. However, for economic reasons a container need only be sufficiently impermeable to the components of the aqueous solution for a limited period of time, for example, the anticipated time delay between manufacture and use.
- the container itself may be in the form of a sachet for accommodating a single towelette or a bag or box for accomodating a plurality of towelettes. In the latter cases the bags or boxes are preferably resealable tj2 minimise evaporation of the aqueous solutions.
- the binder may conveniently be applied to the nonwoven fabric by making an aqueous solution (or emulsion) of the binder and applying it to the fabric by, for example, a roller or a spray gun.
- the nonwoven fabric may simply be dipped in the aqueous solution (or emulsion).
- the nonwoven fabric is preferably dried, and is then cut and, if desired, folded.
- the nonwoven fabric may then either be wetted by the aqueous solution and inserted in a container or inserted in a container and wetted. It should be understood that it is not essential to dry the nonwoven fabric after the application of the binder although drying is preferred for ease of handling.
- a sheet of 24 pound (25 x 38 inch - 500 ' ream) (10.9 Kg - 27.7 96.5 cm) high groundwood, unsized paper was immersed in water for two minutes. The wet sheet was found to have a tensile strength of approximately 0.59 pounds (0.27 Kg).
- VINOL Trade Mark
- PVOH polyvinyl alcohol
- Example 2 Two sheets of paper were prepared and dried as in Example 2. However, instead of immersion in water both sheets were immersed in an aqueous solution containing 5% (by weight) boric acid at room temperature.
- the other wet sheet was then immersed in a large quantity of water for a further two minutes and when tested was found to have a wet tensile strength of less than 0.8 pounds (0.365 Kg).
- a sheet of paper was prepared and dried as in Example 2. The sheet was then immersed in an aqueous solution containing 5% (by weight) boric acid at room temperature for 1 year. On removal from the solution there was no detectable reduction in tensile strength as measured by finger pull.
- PVINOL 540 is 87% to 89% hydrolysed polyvinyl acetate of high viscosity (40 - 50 cps) marketed by Applicants).
- 80% hydrolysed PVOH is commonly known to have reverse solubility, i.e. is insoluble in water above 20°C but is soluble at room temperature. For this reason towelettes should advantageously be coated with this material for use in high temperature atmospheres.
- the dried paper was then immersed for two minutes in a 5% boric acid solution and its wet tensile strength determined by Instron (C) and compound with that of the base stock (A) and the coated sheet without boric acid (B). The results are reported in Table 2 below. The resolubility was demonstrated by further immersion of the boric acid treated sheet in plain water for two minutes (D).
- VINOL compositions were applied to a 24 lb./3300 ft. 2 (10.9 Kg/307 sq. meters) base stock and dried at 250°F (120°C) for 30-90 seconds, as required.
- the amount of PVOH add-on varied due to viscosity differences so that the measured wet tensile values are not directly relatable between the grades.
- Table 4 The water soluble salts listed in Table 4 below are believed to be suitable substitutes in place of boric acid, (which is also listed for comparison) at concentrations of up to 20% (by weight) in the articles of this invention. Table 4 shows the minimum concentration causing precipitation of the compound dissolved in a 5% solution of polyvinyl alcohol (98-99% hydrolysed, degree of polymerization 1700-1800).
- a 60% vinyl acetate-40% ethylene copolymer emulsion containing 4% PVOH (75% VINOL 205 and 25% VINOL 523) (by weight) of the copolymer, and containing a total of 52% solids was cast to form a film of 15 mil wet thickness and air dried. While the film retained its definition when immersed in water, it exhibited practically no wet tensile strength as evidenced by the fact that it could not suspend its own weight.
- the film When immersed in a 5% boric acid solution, the film exhibited surprisingly good wet tensile strength and was highly elastic. However, this film removed from the boric acid solution was redispersed in plain water in less than two minutes.
- the treated film in contact with boric acid solution retained wet tensile strength for more than 30 days at 130°F (54.4°C). At 160°F (71.1°C) the film retained wet tensile strength for 3 days indicating excellent film stability and shelf life at the elevated temperature that may be experienced under storage conditions.
- Example 11 The same emulsion as employed in Example 11 was diluted and applied to a paper substrate.
- the emulsion was diluted with water to a 25% total solids content and applied to both sides of a 42 pound/3300 square foot (19 Kg/307 mg/square meters) paper substrate, and the treated paper dried at 120°C in a forced air oven.
- the pick-up was 3.5 pounds (1.59 Kg) dry emulsion.
- the paper in the foregoing example had a relatively low dried emulsion add-on. At higher add-on levels or lower basis weight substrate greater relative increase in tensile strength may be realized.
- boric acid is employed as the agent for increasing the wet strength of the nonwoven fiber sheet during storage and use
- certain soluble salts known to react with polyvinyl alcohol to effect precipitation or gelling thereof may be employed. These are less preferred than boric acid, however, since larger concentrations of these are required for the desired purpose. Examples of such salts are set out in Table 4 hereinbefore.
Landscapes
- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Dispersion Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Paper (AREA)
Abstract
Description
- This invention relates to a moist packaged towelette and to a method of making the same.
- Moist packaged towelettes are generally made by coating a sheet of nonwoven fabric, usually absorbent paper, with a binder and storing the coated fabric in contact with an aqueous solution in a container. The aqueous solution typically contains alcohol and, for example, a perfume or deodorant. The binder increases the structural integrity of the nonwoven fabric and prevents it disintegrating in the aqueous solution. (For the avoidance of doubt the term "nonwoven fabric" as used herein includes fabrics comprising carded or randomly orientated or cross-laid fibres. The fibres may comprise, for example, natural or regenerated cellulose, other synthetic or proteinaceous fibres of biodegrade materials, or mixtures of these).
- Various binders have been proposed but all which are known to us have the disadvantage that the coated fabric maintains a high structural integrity even after prolonged exposure to water. This can result in blocked drains.
- One known binder for nonwoven fabrics which are not intended to be exposed to moisture is polyvinyl alcohol. Whilst nonwoven fabrics provided with this binder have excellent structural integrity in the dry they disintegrate rapidly when immersed in water.
- We have discovered that a nonwoven fabric provided with a binder comprising polyvinyl alcohol will retain a high structural integrity in contact with an aqueous solution provided that the aqueous solution contains a sufficient concentration of a compound to prevent the polyvinyl alcohol dissolving in the aqueous solution. When the solution is diluted the polyvinyl alcohol dissolves thereby weakening the structural integrity of the towelette.
- Accordingly, the present invention provides a moist packaged towelette comprising a sheet of nonwoven fabric provided with a binder and maintained in contact with an aqueous solution in a container characterized in that said binder is polyvinyl alcohol and said aqueous solution contains a compound which is present in said solution at a sufficient concentration to prevent said polyvinyl alcohol dissolving in said aqueous solution but which, when diluted in excess water, permits said polyvinyl alcohol to dissolve in said excess water thereby reducing the structural integrity of said towelette.
- Compounds which will prevent polyvinyl alcohol dissolving in aqueous solutions are well known and examples are listed in "Polyvinyl Alcohol", 1973; Finch C.A., John Wiley & Sons Ltd., Table 2.3 at page 40. Substantially all of these compounds (which comprise boric acid and water soluble'salts) will, when dissolved in excess water, permit the polyvinyl alcohol to dissolve thereby reducing the structural integrity of the nonwoven fabric. It is, of course, a simple procedure to check if a particular compound is suitable.
- Of the available compounds boric acid is presently preferred and preferably comprises at least 1% (by weight) of the aqueous solution with 3% to 5% (by weight) being preferred and 4% to 5% (by weight) being more preferred.
- One of the problems associated with using a water soluble salt as the compound is that the required concentration in the aqueous solution is so high that, in many cases, the salt crystalizes on the skin when the towelette is used. We strongly recommend that the salts which are used should be those which need be present to no more than 40% (by weight) of the aqueous solution and, more preferably, to no more than 20% (by weight) of the aqueous solution.
- If a salt is to be used then we recommend sodium sulphate at a concentration of between 3% and 20% (by weight) of the aqueous solution and more preferably between 7% and 20% (by weight) of the aqueous solution.
- Polyvinyl alcohol is generally produced by the hydrolysis of polyvinyl acetate. Pure polyvinyl alcohol (i.e. 100% hydrolysed polyvinyl acetate) is relatively insoluble in water at room temperature when compared with 80% to 99% hydrolysed polyvinyl acetate. Accordingly, the binder preferably comprises a mixture of polyvinyl alcohol and polyvinyl acetate. If desired the polyvinyl alcohol may comprise as little as 1% (by weight) of such a mixture although it preferably comprises between 80% and 95% thereof.
- Mixtures (emulsions) comprising vinyl acetate-ethylene copolymers and polyvinyl alcohol may also be used as a binder. In such a case the polyvinyl alcohol preferably comprises from 1% to 10% (by weight) of the binder and probably acts as a protective colloid. If desired the binder may also contain polyvinyl acetate and preferably between 5 and 25% .(by weight) thereof. One particularly preferred range of binders comprises (by weight) 1 to 10% of 80 - 90% hydrolysed polyvinyl acetate and the balance vinyl acetate-ethylene copolymers. Preferably the vinyl acetate-ethylene copolymers contain (by weight) not more than 45% vinyl acetate and not more than 60% ethylene.
- In all the above cases the weight of the binder is preferably between 5% and 50% of the weight of the untreated nonwoven fabric.
- The present invention also provides a method for making a moist packaged towelette which method comprises the step of wetting a sheet of nonwoven fabric provided with a binder by bringing said sheet into contact with an aqueous solution characterized in that said binder comprises polyvinyl alcohol and said aqueous solution contains a sufficient concentration of a compound which prevents the polyvinyl alcohol dissolving in the aqueous solution but which, when dissolved in excess water, allows the polyvinyl alcohol to dissolve in the water thereby reducing the structural integrity of the towelette.
- The present invention also provides a method for making a moist packaged towelette which method comprises taking a sheet of nonwoven fabric which has been provided with a binder and packaging said sheet of treated material in contact with an aqueous solution in a container characterized in that said binder comprises polyvinyl alcohol and said aqueous solution contains a sufficient concentration of a compound which prevents the binder from dissolving in the aqueous solution but which, when dissolved in excess water, allows the binder to dissolve in the water thereby reducing the structural integrity of the towelette.
- Preferably said compound is boric acid and advantageously said aqueous solution comprises at least 1% (by weight) of said compound with 3% to 5% (by weight) being preferred and 4% to 5% (by weight) being more preferred.
- The container should preferably be impermeable to all the components of the aqueous solution. However, for economic reasons a container need only be sufficiently impermeable to the components of the aqueous solution for a limited period of time, for example, the anticipated time delay between manufacture and use. The container itself may be in the form of a sachet for accommodating a single towelette or a bag or box for accomodating a plurality of towelettes. In the latter cases the bags or boxes are preferably resealable tj2 minimise evaporation of the aqueous solutions.
- The binder may conveniently be applied to the nonwoven fabric by making an aqueous solution (or emulsion) of the binder and applying it to the fabric by, for example, a roller or a spray gun. Alternatively, the nonwoven fabric may simply be dipped in the aqueous solution (or emulsion).
- Once treated the nonwoven fabric is preferably dried, and is then cut and, if desired, folded. The nonwoven fabric may then either be wetted by the aqueous solution and inserted in a container or inserted in a container and wetted. It should be understood that it is not essential to dry the nonwoven fabric after the application of the binder although drying is preferred for ease of handling.
- For a better understanding of the invention reference will now be made to the following non-limiting examples.
- A sheet of 24 pound (25 x 38 inch - 500 'ream) (10.9 Kg - 27.7 96.5 cm) high groundwood, unsized paper was immersed in water for two minutes. The wet sheet was found to have a tensile strength of approximately 0.59 pounds (0.27 Kg).
- A sheet of the same paper used in Example 1 was impregnated with a solution of VINOL (Trade Mark) 205 polyvinyl alcohol (PVOH) to the extent of 4 pounds (1.80 Kg) dry add-on and dried in a 120°C forced air oven. After immersion in water for two minutes the wet sheet was found to have a tensile strength of 0.59 pounds (0.27 Kg), i.e. approximately equal to the wet sheet in Example 1. (VINOL 205 is 87% to 89% hydrolysed polyvinyl acetate of low viscosity (4-6 cps) marketed by Applicants).
- Two sheets of paper were prepared and dried as in Example 2. However, instead of immersion in water both sheets were immersed in an aqueous solution containing 5% (by weight) boric acid at room temperature.
- After immersion for two minutes one wet sheet was tested and found to have a tensile strength of 1.6 pounds (0.73 Kg), i.e. nearly 3 times the tensile strength in Example 1 and 2.
- The other wet sheet was then immersed in a large quantity of water for a further two minutes and when tested was found to have a wet tensile strength of less than 0.8 pounds (0.365 Kg).
- A sheet of paper was prepared and dried as in Example 2. The sheet was then immersed in an aqueous solution containing 5% (by weight) boric acid at room temperature for 1 year. On removal from the solution there was no detectable reduction in tensile strength as measured by finger pull.
- In order to determine the probable shelf life of the packaged towelette films of 15 ml. (0.038 cm) wet thickness were separately cast from VINOL 205 and VINOL 540 PVOH and dried at .room temperature. Strips of the films of 1 x 6 inches (2.54 x 15.24 cm) were then immersed in an aqueous solution containing 5% (by weight) boric acid at various temperatures. The probable shelf life of the packaged towelette at various temperatures is indicated in Table 1.
- In contrast all the films dissolved within 5 minutes when immersed in ordinary water. (VINOL 540 is 87% to 89% hydrolysed polyvinyl acetate of high viscosity (40 - 50 cps) marketed by Applicants). 80% hydrolysed PVOH is commonly known to have reverse solubility, i.e. is insoluble in water above 20°C but is soluble at room temperature. For this reason towelettes should advantageously be coated with this material for use in high temperature atmospheres.
- A high groundwood stock paper substrate (24 pound/3300 ft. 2 = 10.9 Kg/307 sq. meters) was treated with a 15% aqueous solution of VINOL 205 PVOH applied with a No. 10 Mayer rod separately to each side of the paper and dried at 250°F ( 120°C) for 30 seconds. The coated first side was dried before applying the coat- . ing to the other side.
- The dried paper was then immersed for two minutes in a 5% boric acid solution and its wet tensile strength determined by Instron (C) and compound with that of the base stock (A) and the coated sheet without boric acid (B). The results are reported in Table 2 below. The resolubility was demonstrated by further immersion of the boric acid treated sheet in plain water for two minutes (D).
- Further studies were carried out to determine the effect of boric acid concentration on the wet tensile strength of PVOH in pregnated papers. These studies were made on paper sheets of a 42 pound/3300 sq. ft. stock (19 kg/307 sq. meters) each respectively immersed in boric acid solution of successively increasing concentrations. It was found that the wet tensile strength increased almost linearly with concentration from 0.72 pounds (~ .33 kg) at zero boric acid to 1.41 pounds (~ 0.64 kg) at 5% boric acid.
-
- Each of these VINOL compositions were applied to a 24 lb./3300 ft.2 (10.9 Kg/307 sq. meters) base stock and dried at 250°F (120°C) for 30-90 seconds, as required. The amount of PVOH add-on varied due to viscosity differences so that the measured wet tensile values are not directly relatable between the grades.
-
- The water soluble salts listed in Table 4 below are believed to be suitable substitutes in place of boric acid, (which is also listed for comparison) at concentrations of up to 20% (by weight) in the articles of this invention. Table 4 shows the minimum concentration causing precipitation of the compound dissolved in a 5% solution of polyvinyl alcohol (98-99% hydrolysed, degree of polymerization 1700-1800).
-
- From the foregoing tests it appears that while the soluble salts listed in Table 4 above, such as sodium sulphate, can be employed to retard solubilization of polyvinyl alcohol films, greater concentrations i.e. about 7% to about 20%, are required than when using boric acid.
- As projected from the data set forth in Tables 4 and 5, potassium citrate appears to be even more efficient than sodium sulphate.
- The specific behaviour of boric acid in retaining solubilization of PVOH film is not attributable to the pH of the boric acid solution. Whereas a VINOL 205 film was insoluble in 5% boric acid solution, such film was readily dissolved respectively, in 5% aqueous solution of citric and phosphoric acid and a 0.7% solution of fumaric acid.
- A 60% vinyl acetate-40% ethylene copolymer emulsion containing 4% PVOH (75% VINOL 205 and 25% VINOL 523) (by weight) of the copolymer, and containing a total of 52% solids was cast to form a film of 15 mil wet thickness and air dried. While the film retained its definition when immersed in water, it exhibited practically no wet tensile strength as evidenced by the fact that it could not suspend its own weight.
- When immersed in a 5% boric acid solution, the film exhibited surprisingly good wet tensile strength and was highly elastic. However, this film removed from the boric acid solution was redispersed in plain water in less than two minutes.
- The treated film in contact with boric acid solution retained wet tensile strength for more than 30 days at 130°F (54.4°C). At 160°F (71.1°C) the film retained wet tensile strength for 3 days indicating excellent film stability and shelf life at the elevated temperature that may be experienced under storage conditions.
- The same emulsion as employed in Example 11 was diluted and applied to a paper substrate.
- The emulsion was diluted with water to a 25% total solids content and applied to both sides of a 42 pound/3300 square foot (19 Kg/307 mg/square meters) paper substrate, and the treated paper dried at 120°C in a forced air oven. The pick-up was 3.5 pounds (1.59 Kg) dry emulsion.
- A sample of the dried emulsion treated paper, as determined by conventional Instron test, showed a wet tensile strength after immersion in water, of 1.08 pounds (0.49 Kg) as compound to the untreated stock which showed a wet tensile of 0.72 pounds (0.33 Kg).
- A duplicate sample of the dried emulsion treated paper immersed in 5% boric acid solution for 2 minutes when tested by Instron exhibited a tensile of 1.41 pounds (0.64 Kg). When reimmersed in plain water for 2 minutes, the paper returned to about its initial wet strength, 1.09 pounds (0.49 Kg).
- Another duplicate sample of the dried emulsion treated paper was immersed in 5% boric acid solution for 30 minutes maintained about the same tensile strength as that previously shown for the boric acid treatment while the water value on reimmersion decreased to 0.91 pounds (0.41 Kg).
- It should be noted that the paper in the foregoing example had a relatively low dried emulsion add-on. At higher add-on levels or lower basis weight substrate greater relative increase in tensile strength may be realized.
- While in Example 10 and 11 boric acid is employed as the agent for increasing the wet strength of the nonwoven fiber sheet during storage and use, certain soluble salts known to react with polyvinyl alcohol to effect precipitation or gelling thereof, may be employed. These are less preferred than boric acid, however, since larger concentrations of these are required for the desired purpose. Examples of such salts are set out in Table 4 hereinbefore.
-
- From the foregoing results, it appears that while the soluble salts, such as sodium sulphate, can be employed to retard solubilization of polyvinyl acetate films, somewhat greater concentrations, i.e. about 3% to about 20%, are required than when using boric acid.
Claims (15)
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US870551 | 1978-01-18 | ||
US05/870,552 US4258849A (en) | 1978-01-18 | 1978-01-18 | Flushable towelette |
US870552 | 1978-01-18 | ||
US05/870,551 US4245744A (en) | 1978-01-18 | 1978-01-18 | Polyvinyl acetate latex impregnated towelette |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0003186A1 true EP0003186A1 (en) | 1979-07-25 |
EP0003186B1 EP0003186B1 (en) | 1982-06-23 |
Family
ID=27128167
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP79300077A Expired EP0003186B1 (en) | 1978-01-18 | 1979-01-17 | Moist packaged towelette and method of making same |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0003186B1 (en) |
DE (1) | DE2963135D1 (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2152369A (en) * | 1984-01-07 | 1985-08-07 | Paul Howard Finn | Hair treatment means |
WO1996030576A1 (en) * | 1995-03-31 | 1996-10-03 | Kimberly-Clark Worldwide, Inc. | Premoistened, flushable, disposable and biodegradable wet wipes |
WO1998032906A1 (en) * | 1997-01-28 | 1998-07-30 | Camelot Superabsorbents Limited | Process for bonding fibrous web |
US5952251A (en) * | 1995-06-30 | 1999-09-14 | Kimberly-Clark Corporation | Coformed dispersible nonwoven fabric bonded with a hybrid system |
US6433245B1 (en) | 1997-11-25 | 2002-08-13 | The Procter & Gamble Company | Flushable fibrous structures |
EP1285985A1 (en) * | 2001-08-22 | 2003-02-26 | Air Products Polymers, L.P. | Disintegratable pre-moistened wipes substantially free of boric acid and its derivatives and lotion therefor |
WO2005060931A1 (en) * | 2003-12-01 | 2005-07-07 | Kimberly-Clark Worldwide, Inc. | Water disintegratable cleansing wipes |
WO2013124804A2 (en) | 2012-02-24 | 2013-08-29 | Ronco Danilo | Cellulose-based paper containing cleansing agents capable of disaggregating in aqueous liquids and of being wound into continuous rolls |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3692725A (en) * | 1970-10-28 | 1972-09-19 | Kimberly Clark Co | Stabilized binder for water-flushable non-woven webs |
US3886112A (en) * | 1973-12-17 | 1975-05-27 | Polymer Films Inc | Polyvinyl alcohol based composition and articles made therefrom |
GB1510667A (en) * | 1975-01-06 | 1978-05-10 | Dexter Corp | Non-woven material for disposable wet wipes |
-
1979
- 1979-01-17 DE DE7979300077T patent/DE2963135D1/en not_active Expired
- 1979-01-17 EP EP79300077A patent/EP0003186B1/en not_active Expired
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3692725A (en) * | 1970-10-28 | 1972-09-19 | Kimberly Clark Co | Stabilized binder for water-flushable non-woven webs |
US3886112A (en) * | 1973-12-17 | 1975-05-27 | Polymer Films Inc | Polyvinyl alcohol based composition and articles made therefrom |
GB1510667A (en) * | 1975-01-06 | 1978-05-10 | Dexter Corp | Non-woven material for disposable wet wipes |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2152369A (en) * | 1984-01-07 | 1985-08-07 | Paul Howard Finn | Hair treatment means |
WO1996030576A1 (en) * | 1995-03-31 | 1996-10-03 | Kimberly-Clark Worldwide, Inc. | Premoistened, flushable, disposable and biodegradable wet wipes |
US5629081A (en) * | 1995-03-31 | 1997-05-13 | Kimberly-Clark Tissue Corporation | Premoistened, flushable, disposable and biodegradable wet wipes |
US5952251A (en) * | 1995-06-30 | 1999-09-14 | Kimberly-Clark Corporation | Coformed dispersible nonwoven fabric bonded with a hybrid system |
WO1998032906A1 (en) * | 1997-01-28 | 1998-07-30 | Camelot Superabsorbents Limited | Process for bonding fibrous web |
US6433245B1 (en) | 1997-11-25 | 2002-08-13 | The Procter & Gamble Company | Flushable fibrous structures |
EP1285985A1 (en) * | 2001-08-22 | 2003-02-26 | Air Products Polymers, L.P. | Disintegratable pre-moistened wipes substantially free of boric acid and its derivatives and lotion therefor |
WO2005060931A1 (en) * | 2003-12-01 | 2005-07-07 | Kimberly-Clark Worldwide, Inc. | Water disintegratable cleansing wipes |
US7285520B2 (en) | 2003-12-01 | 2007-10-23 | Kimberly-Clark Worldwide, Inc. | Water disintegratable cleansing wipes |
WO2013124804A2 (en) | 2012-02-24 | 2013-08-29 | Ronco Danilo | Cellulose-based paper containing cleansing agents capable of disaggregating in aqueous liquids and of being wound into continuous rolls |
Also Published As
Publication number | Publication date |
---|---|
DE2963135D1 (en) | 1982-08-12 |
EP0003186B1 (en) | 1982-06-23 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4372447A (en) | Flushable towelette | |
US4258849A (en) | Flushable towelette | |
US4343133A (en) | Polyvinyl acetate latex impregnated towelette | |
US4343403A (en) | Polyvinyl acetate latex impregnated towelette | |
US4245744A (en) | Polyvinyl acetate latex impregnated towelette | |
JP2685162B2 (en) | Pre-moistened, flushable napkins impregnated with a binder containing polyvinyl alcohol | |
US4343134A (en) | Flushable towelette | |
EP0905313B1 (en) | Water-disintegratable fibrous sheet containing modified polyvinyl alcohol | |
US4362781A (en) | Flushable premoistened wiper | |
CA1214371A (en) | Binder for pre-moistened paper products | |
US6423804B1 (en) | Ion-sensitive hard water dispersible polymers and applications therefor | |
AU714188B2 (en) | Water-disintegratable fibrous sheet | |
US3692725A (en) | Stabilized binder for water-flushable non-woven webs | |
FI87620C (en) | OMSLAG FOER TOBAKSPRODUKT OCH FOERFARANDE FOER DESS FRAMSTAELLNING | |
EP0003186B1 (en) | Moist packaged towelette and method of making same | |
JP2007531828A (en) | Wipe products containing meltable materials | |
US3684749A (en) | Adhesive composition for gummed tape | |
JPH08502462A (en) | Packaging material | |
HU215568B (en) | Packing device of hose shape particularly sausage-skin from cellulose | |
US2907683A (en) | Fireproofing textiles and the like | |
US2397817A (en) | Wall covering and the like | |
JPS5927613B2 (en) | Manufacturing method of activated carbon holding base material | |
JPS63143068A (en) | Deodorizing sheet like article | |
JPS6335744B2 (en) | ||
TH25163B (en) | Water-degradable fibers |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Designated state(s): DE FR GB IT NL |
|
17P | Request for examination filed | ||
ITF | It: translation for a ep patent filed | ||
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Designated state(s): DE FR GB IT NL |
|
REF | Corresponds to: |
Ref document number: 2963135 Country of ref document: DE Date of ref document: 19820812 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19821215 Year of fee payment: 5 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19821217 Year of fee payment: 5 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19830121 Year of fee payment: 5 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19840801 |
|
NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19840928 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Effective date: 19841002 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee | ||
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19881117 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |