MXPA01009158A - Durable high fluid release wipers - Google Patents

Abstract

A cleaning system is provided comprising a sealable container housing a saturated stack of durable fine spunbond fiber cleaning sheets;the cleaning sheets have an average fiber diameter less than 18 micrometers, a tensile strength of at least 140-g/g/m2 and a basis weight between about 15 g/m2 and 85 g/m2. The cleaning sheets can be provided in stacked form and maintained within a sealed container wherein liquid is retained within the individual sheets as well as throughout the stack over time. The sheets can subsequently be removed from the container and applied to a surface wherein a high percent of the liquid is released from the sheet onto the surface in the initial pass and thereby allowing for improved treatment and/or cleaning of the surface.

Description

HIGH CLEANING FLUID CLEANING PANOS TECHNICAL FIELD The present invention relates to cleaning cloths and more particularly refers to products for delivering fluid comprising non-woven fabrics.

BACKGROUND OF THE INVENTION Pre-moistened or saturated paper and textile wipes have been used in a variety of cleaning and polishing rags. These substrates are often provided in a sealed container and recovered therefrom in a wet or saturated condition (eg pre-wet). The pre-moistened paper towel or cloth wipes away retained liquid when used to clean or polish the desired surface. In addition, fabrics of meltblown fibers have also been used as pre-moistened wipers in various applications and end uses. It is known that fabrics of melt blown fibers are capable of receiving and retaining liquids for extended periods of time. More particularly, fabrics of meltblown fibers are capable of being supplied in a stacked or rolled-up form where, when saturated with a liquid, fabrics of meltblown fibers keep the liquid evenly distributed throughout the pile. Thus, sheets of melt blown fibers can be stacked in a sealable container and liquid can be added thereto. The sealed container can then be stored or shipped as necessary and the stacked meltblown fabric retains the liquid evenly through the stack during the shelf life of the product. Uniformly wet melted blown fiber fabrics provided in a stacked form are described in U.S. Patent Nos. 4,853,281 and 4,833,033 both issued to Win et al. Fabrics of pre-moistened meltblown fibers have found a wide variety of applications including use as polishing cloths, hand wipes, hard surface cleaners and others. By way of example, various applications of the presaturated meltblown fabrics are described in U.S. Patent Nos. 5,656,361 issued to Vogt et al., 5,595,786 issued to McBridge et al. And 5,683,971 issued to Rose et al.

While melt blown fabrics provide liquid absorption and retention characteristics, meltblown fabrics can also provide a metered release of the liquid held there. Therefore, in use it is often difficult to achieve a rapid and substantial release of the liquid from the meltblown material. In addition, in certain cleaning operations, meltblown fabrics may experience fraying, for example, loosening fibers from the fabric. This is particularly problematic in "clean room" operations or in paint preparation processes wherein the production of even small particles such as a lint is highly undesirable. In addition to fraying, tearing or disassociation of the melt blown fabric can also be a problem when used for "heavy duty" applications such as, for example, when cleaning rough and uneven surfaces. Multilayer laminates comprising non-woven fabrics of spunbonded fibers and meltblown fabrics have previously been used in order to provide a wiper cloth that exhibits less fraying and has improved durability. However, even when meltblown fabrics exhibit good liquid absorption and good retention characteristics, these characteristics have not heretofore been easily attainable with the non-woven fabrics of spunbonded fibers. Thus, meltblown fiber fabrics provide such laminates with good liquid retention characteristics and the fabric bonded with outer yarn provides a reduced fraying. As an example, U.S. Patent No. 4,436,780 to Hotchkiss et al. Discloses a spunbond / meltblown / spunbonded laminate having a relatively high base weight meltblown layer between two layers fiber joined with yarn.

Therefore, there is a continuing need for a uniformly wet cleaning cloth and uniformly moistened pre-moistened products thereof, which exhibit improved durability and tear resistance. In addition, there is also a need for such a cleaning cloth and particles thereof exhibiting reduced fraying. Still further, there is a need for such a cleaning cloth that exhibits a high and substantial initial release of the liquid contained therein.

SYNTHESIS OF THE INVENTION The aforementioned needs are met and the problems experienced by those skilled in the art are overcome by the wiping cloths or cleaning sheets of the present invention which comprises a spunbonded fiber cloth having an average fiber size of less than about 18 μ and a basis weight of between about 15 grams per square meter and about 85 grams per square meter. In addition, the sheets desirably provide a substrate that retains the liquid over time and yet this has an initial liquid release of at least about 17%. In addition, the yarn-bonded fiber fabric desirably has a normalized tensile strength greater than 0.13 kilograms per gram per square meter. Still further, the fabric not bound together with fine fiber yarn desirably has an average pore size of less than about 35 microns and a Taber resistance of at least 50 cycles.

In a further aspect of the invention, the wipers attached with fine fiber yarn can be used to provide a cleaning system such as a prepackaged stack of wet spinning wiping cloths having excellent liquid retention in the stack and however, they provide a high release of liquid in use. In this aspect a cleaning product may comprise a sealable container having a liquid and a plurality of cleaning cloths bonded with fine fiber yarn stacked as described herein. The fiber nonwoven fabric bonded with fine fiber yarn within the container desirably has an essentially uniform liquid retention after 30 days where there is no substantial liquid migration into the pile to the bottom of the container and the upper portions of the container. The bottom of the stack retains an essentially equivalent amount of liquid. The stack desirably has a height of less than about 21 centimeters and comprises at least about 10 layers. The sheets can be folded, punched or otherwise processed to provide an easily accessible cleaning cloth having the desired size and shape. The pre-moistened sheets can be removed from the container and applied to a surface to be treated such as, for example, by hand. The fluid is easily released from the sheet on the surface thereby improving the treatment of the surface and / or the cleaning action of the bonded sheet with fine fiber spinning.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partially elevated perspective view of the wiper cloth bonded with knitted fine fiber yarn.

Figure 2 is a perspective view of a sealable container and wiping cloths.

Figure 2A is an exposed side view of the stacked wipers of Figure 2.

Figure 3 is a partially elevated side view of a container of pre-wet cleansing wipes.

Figure 3A is a cross-sectional view of the container and the wiping cloths of Figure 3.

Figure 4 is a graph describing wet leaf weight per leaf over time.

DESCRIPTION OF THE INVENTION With reference to Figure 1, the wiping cloth 10 of the present invention may comprise a section of a non-woven fabric of finely spunbonded fibers 12. Spunbonded fibers have an average fiber diameter of about 17 microns or less and more desirably has an average fiber diameter of between about 5 and 15 microns and still more desirably has an average fiber diameter of between about 8 and 14 microns. As used herein the term "fiber diameter" refers to the longest cross-sectional dimension of the fiber. Desirably, fiber fabrics bonded with yarn have a basis weight of between about 17 grams per square meter and about 85 grams per square meter and more desirably between about 25 grams per square meter and about 68 grams per square meter. Yarn-bonded fiber fabrics desirably have an average pore size of less than about 35 microns and even more desirably an average pore size of between about 15 microns and about 30 microns. In a further aspect, the fabrics bonded with fine fiber yarn desirably have an initial liquid release of about 17% and more desirably an initial liquid release of above 20% and even more desirably an initial liquid release above 25% In addition, cleaning cloths bonded with fine fiber yarn desirably release at least about 50% liquid there within 5 passes and more desirably release at least about 50% liquid there within 3 passes.

Fine spunbonded fibers suitable for use with the present invention may include monocomponent, multicomponent and / or biconstituent fibers. In addition, even when the yarn-bound fibers are typically round, fibers having various geometric or regular shapes can also be used in connection with the present invention. Spunbonded fabrics are known in the art and can be made by various processes such as those described in the United States of America patents No. s 4,692,618 granted to Dorschner and others, 4,340,563 granted to Appel and others, 3,802,817 granted to Matsuki and others and 3,338,992 and 3,341,394 granted to Kinney, 3,502,763 granted to Hartman and 5,382,400 granted to Pike and others, whose complete contents of each of the aforementioned references are incorporated here by this mention. However, spunbonded fabrics commonly comprise fibers having an average fiber size of about 20 microns or more. In this aspect, it is possible to achieve fabrics bonded with fine fiber yarn, having an average fiber size of less than 18 micrometers, using a forming equipment linked with traditional spinning by using the melt flow rate resins. high such as those described in U.S. Patent No. 5,681,646 issued to Ofosu et al. or the after-treatment of non-woven fabrics and / or fibers such as those described in U.S. Patent No. 5,244,482 granted to Hassenboehler, Jr. and others and in the United States of America Patent No. 5,759,926 granted to Pike and others whose complete contents of each of these mentioned references are incorporated herein by this mention. High melt flow rate (MFR) polymers, for the purposes of making yarn-bound fibers, include polymers having a high melt flow rate of at least about 35 and desirably a melt flow rate. between about 45 and about 200. The fabric joined with fine fiber yarn may comprise polyolefin, polyester, polyamide (for example nylon) or other suitable polymers to form the fibers bonded with yarn. Desirably the spunbonded fiber comprises a polyolefin and in a particularly preferred embodiment the fine spunbonded fibers comprise propylene polymer.

The production of high melt flow rate polyolefins can be achieved by several methods. As an example, high melt flow rate polyolefins can be achieved when starting with a conventional low melt flow polyolefin through the action of free radicals which degrade the polymer to increase the melt flow rate. Such free radicals can be created and / or made more stable through the use of a prodegradant such as a peroxide, an organometallic compound or a transition metal oxide. Depending on the prodegradante chosen, the stabilizers can be useful. An example of a way to make a high melt flow polyolefin of a conventional low melt flow polyolefin is to incorporate peroxide into the polymer. The addition of peroxide to polymers is taught in U.S. Patent No. 5,213,881 issued to Timmons et al. And the addition of peroxide to polymer pellets is described in U.S. Patent No. 4,451,589 granted to Morman and others, whose full contents of the aforementioned references are incorporated herein by this mention. The addition of peroxide to a polymer for spunbonding applications can be done by adding up to 1,000 parts per million of peroxide to the commercially available low melt flow rate polyolefin polymer and mixing thoroughly. The resulting modified polymer will have a melt flow rate of approximately two to three times that of the starting polymer, depending on the rate of peroxide addition and mixing time. In addition, the high melt flow rate polymers may comprise polymers having a narrow molecular weight distribution and low polydispersity (relative to conventional olefin polymers such as those described by the Ziegler-Natta catalysts) and include those catalyzed by "metallocene catalysts", "single site catalysts", "constricted geometry catalysts" and / or other similar catalysts. Examples of such catalysts and / or polyolefins made therefrom are described in, but are not limited to, US Pat. Nos. 5,153,157 to Canish, 5,064,802 to Stevens et al., 5,374,696 to Rosen. and others, 5,451,450 granted to Elderly and others, 5,204,429 granted to Kaminsky and others, 5,539,124 granted to Etherton and others, and United States of America Patents Nos. 5,278,272 and 5,272,236 both granted to Lai et al., United States Patent of US Pat. No. 5,554,775 issued to Krishnamurti et al. And U.S. Patent No. 5,539,124 issued to Etherton et al. Exemplary polymers have a melt flow rate of about 35 or greater, and as a particular example, they may have a melt flow rate of about 50. In addition, the polymers formed by such catalysts desirably have a narrow molecular weight having a polydispersity number of about 2.5 or less and even more desirably of about 2. Exemplary commercially available polymers having a high melt flow rate, narrow molecular weight distribution and low polydispersity are available from Exxon Chemical Company under the trade name ACHIEVE.

The layer of the spunbonded fibers is bonded to provide a durable and coherent nonwoven fabric. By way of example only, the non-woven fabric can be thermally bonded, ultrasonically, adhesively and / or mechanically. The fiber fabric bonded with fine yarn is desirably patterned. As an example and with reference to Figure 1, the spunbonded fiber sheet 10 can be knitted to provide a fabric having numerous discrete and small bonding points 14. An example joining process is the point bonding. thermal and this process generally involves passing one or more layer to be joined between heated rollers such as, for example, an engraved pattern roller and a second bonding roller. The engraved roller has a pattern in some way so that the fabric does not overlap its entire surface, and the second roller can be smooth or patterned. As a result of this, several patterns have been developed for the engraved rolls for functional as well as aesthetic reasons. Exemplary link patterns include, but are not limited to those described in US Pat. Nos. 3,855,046 to Hansen et al., 5,620,779 to Levy et al., 5.962112 to Haynes et al. And United States of America design patent No. 390,708 granted to Brown. In addition, the fiber sheet bonded with fine yarn can be joined by continuous patterns or stitching. As particular examples, the spunbonded fiber sheet can be bonded along the periphery of the sheet or simply across the width or transverse direction (CD) of the fabric adjacent the edges. Desirably, the bonded areas comprise between about 5% and about 30% of the surface area of the fabric and more desirably comprise between about 10% and about 20% of the total surface area of the fabric and even more desirably of between about 12% and about 17% of the total surface area of the fabric. The fabrics bonded with finely bonded fiber yarn desirably have a Taber resistance of at least about 50 cycles and even more desirably a Taber resistance of about 65 cycles or more. In a further aspect, the fine spunbonded fiber fabrics desirably have a tensile strength in the machine direction of at least about 140-g per g / square meter and more desirably have a tensile strength. in excess of about 180 grams per g / square meter and even more desirably a tensile strength in excess of about 210 g per g / square meter. As an example, a nonwoven fabric of 51 grams per square meter of a polypropylene yarn bonded together desirably has a tensile strength in excess of about 7 kilograms and more desirably a tensile strength in excess of about of 9 kilograms and even more desirably a tensile strength of at least about 10 kilograms.

The spunbonded fiber sheet can be perforated or have several surface projections to vary the tactile attributes of the bonded fiber sheet with fine spinning. Additionally, one or more of the surfaces of the sheet bonded with fine fiber yarn can be made abrasive by the addition of particulate matter to the sheet. Still further, one or more surfaces of the sheet can be made abrasive and / or provide a rough surface layer by forming a layer of macro fibers on the bonded sheet with fine fiber spinning. Desirably, the macrofibers have an average fiber diameter of about 25 microns or more and may comprise spunbond or meltblown fibers. As an example, the macro fibers may comprise fibers having diameters of about 40 microns or more and may be formed as described in U.S. Patent No. 4,659,609 to Lamers et al; the complete contents of which are incorporated here by this mention. The abrasive layer desirably has very little or no liquid retention properties and has a basis weight of less than about 15 grams per square meter and even more desirably has a basis weight of about 10 grams per square meter or less.

The non-woven fabrics bonded with stacked fine fiber yarn can be pre-wetted and / or saturated with liquid and desirably capable of substantially uniformly retaining the liquid over extended periods of time. Therefore, non-woven fabrics bonded with stacked fine fiber yarn can be pre-moistened and then stored in a sealed container until needed. This is particularly advantageous in that the cleaners taken from the top of the stack will contain essentially the same amount of liquid as those taken after and / or from the bottom of the stack. Even though non-woven fabrics of spunbonded fiber have been used in various cleaning or wiping cloth applications so far, spunbonded nonwoven fabrics have not provided a substrate capable of substantially uniformly retaining the liquid in the yarn. a pile with time. This has been previously achieved only with melt blown fiber fabrics or composite fabrics employing them. However, the fabric joined with stacked fine fiber yarn maintains an essentially uniform liquid distribution for at least 30 days. In this aspect the stack undergoes a migration of insubstantial liquid over time and, in particular, prevents migration where the top of the stack contains essentially less liquid in relation to the amount of liquid inside the bottom of the stack. Thus, the sealed container houses the non-woven fabric bonded with pre-moistened fine fiber yarn and the stacked sheets undergo a migration of insubstantial liquid during storage and / or shipment of the product. The average percentage by weight of liquid within the leaves desirably varies by less than about 10% over 30 days and more desirably varies by less than about 7% over 30 days and even more desirably varies by less than about 5% about 30 days and even more desirably varies by less than about 3% over 30 days.

As used herein, the term "stack" is used broadly to include any collection of spun-bonded fiber sheets wherein there is a plurality of surface-to-surface interfaces. This not only includes a vertically stacked collection of individual sheets, but also includes a horizontally stacked collection of individual sheets as well as a rolled or folded collection of a continuous sheet material. In the case of a horizontal stack according to this invention, where the individual sheets are standing on the edge, the concentration of liquid will remain essentially the same from the top to the bottom of each individual sheet, as well as from sheet to sheet. A rolled or folded product comprising a continuous sheet desirably has perforated or over-bent lines of weakness which allow separation into smaller individual sheets of a desired shape and size. Notably, when wound on a roll, the concentration of liquid within the fine fiber spunbonded roll equilibrates to essentially equal concentrations, regardless of the orientation of the roll within a container.

The stack desirably has at least about 10 layers and more desirably has between about 10 and about 250 layers and even more desirably between about 20 and about 200 layers. As used herein the layers refer to the number of fabric interleaves. In this aspect, a rolled sheet will be considered to have a fabric interface or a "layer" for each revolution. In addition, a sheet folded one or more times will similarly create additional fabric interlayers or layers; as an example, 20 individual overlapping sheets in half-fold (eg folded in half) create 39 layers. The stack desirably has a height of less than about 21 centimeters and still more desirably has a height of between 12 centimeters and about 20 centimeters. With reference to Figures 2 and 2A, the stack height (H) is at the height of the overlapping sheets 22 inside the container 20. With reference to Figures 3 and 3A and the rolled cleaning cloths shown therein, the stack 31 has a height (H) corresponding to the height or width of the roll of the web material 32 within the container 30.

Fiber sheets joined with stacked and wet fine fiber yarn can be maintained over time in a sealable container such as, for example, in a cuvette with a clamped lid, sealable plastic bags, containers, jars, tubes and the like. Desirably, stacked and wet spunbonded fiber sheets are maintained in a resealable container. The use of a resealable container is particularly desirable when using highly volatile liquid compositions since substantial amounts of liquid can evaporate while the first sheets are used thereby leaving the remaining sheets with little or no liquid. Exemplary resealable containers and dispensers include, but are not limited to those described in US Pat. Nos. 4,171,047 issued to Doyle et al., 4,353,480 issued to McFadyen, 4,778,048 issued to Kaspar et al., 4,741,944. granted to Jackson et al., 5,595,786 granted to McBride and others; the complete contents of the aforementioned references are incorporated herein by this mention. Fiber-bonded and fine fiber sheets can be incorporated or oriented into the container as desired and / or can be folded as desired in order to improve efficiency of use as is known in the art.

A selected amount of liquid is added to the container so that the fine spinning fiber wiping cloths contain the desired amount of liquid. Typically, the stacked sheet material is placed in the container and the liquid is subsequently added thereto. The fiber wiper cloth bonded with fine yarn can subsequently be used to clean a surface and / or act as a vehicle to deliver and apply the liquid to a surface. Cleaning cloths bonded with fine fiber yarn moistened and / or saturated can be used to treat various surfaces. As used herein, "treating" surfaces is employed in the broad sense and includes, but is not limited to, cleaning, polishing, cleaning, washing, disinfecting, scrubbing, sanitizing and / or applying agents. active to them. As an example, fabrics bonded with fine fiber yarn are well suited for treating hard surfaces such as, for example, countertops, tables, furniture, workstations, windows, laboratory tops, equipment , machinery, floors, walls and others. Suitable hard surfaces include metal, glass, wood, stone, plastic and others. In addition, fine fiber non-woven fabrics can be used to treat various other surfaces such as, for example, treating the skin. The wipers attached with fine fiber yarn are very suitable for use as hand or face cleaning cloths and are similarly well suited for use in various medical and / or veterinary applications as well. Notably, fabrics bonded with fine fiber yarn will exhibit considerably less fraying than fabrics of melt blown fibers and will therefore be better suited for use in connection with clean room applications and other uses in which fraying contamination is of considerable concern. In addition, the improved tensile strength provides a more durable cleaning cloth better suited for more rigorous or "heavy duty" cleaning operations. In addition, a higher liquid release is desirably high for many uses such as, for example, when a surface is disinfected. Frequently a surface requires a broad disinfectant to thoroughly wet the surface as well as to allow the surface to remain wet for a sufficient period of time until the disinfectant is effective.

The amount and composition of the liquid added to the bonded with fine fiber yarn will vary with the desired application and / or the function of the cleaning cloths. As used herein the term "liquid" includes, but is not limited to solutions, emulsions, suspensions and others. Therefore, the liquids may comprise and / or contain one or more of the following: disinfectants; antiseptics; diluents; surfactants, such as nonionic, anionic, cationic and amphoteric surfactant; emollients; skin conditioners; antimicrobial agents; sterilizers; sporicides; germicides; bactericides; fungicides; virucides; protozoacidos; algicides; bacteriostats; fungistats; virustates; sanitizers; antibiotics; pesticides; bug repellents and others. Frequently the liquid will comprise an aqueous solution or emulsion. As an example, aqueous alcoholic compositions suitable for use with non-woven fabrics of spunbonded and fine fibers. The term "aqueous alcoholic composition" embraces any composition that contains both water and alcohol. The alcohol desirably comprises a saturated aliphatic alcohol having from one to about six carbon atoms. By way of illustration only, the alcohol can be methanol, ethanol, propanol, isopropanol, butanol, t-butanol, 2-butanol, pentanol, 2-pentanol, hexanol, 2,3-dimethyl-1-butanol and others, including mixtures of two or more alcohols. For example, the aqueous alcohol composition may be an aqueous isopropanol composition. As a particular example, the aqueous alcohol composition may comprise from about 20% to about 99% by volume of alcohol and from about 1% to about 80% by volume of water. Even more desirably, the aqueous alcohol composition may comprise between about 65% to 95% by volume of alcohol and from about 35% to about 5% by volume of water. As a specific example, the alcohol composition may comprise about 85% isopropyl alcohol and about 15% deionized water. As a further specific example, the aqueous alcohol composition may comprise a liquid suitable for external disinfection of the skin and other surfaces and may comprise about 29.5% deionized water, about 70% isopropyl alcohol and about 0.5% benzalkonium chloride.

Optionally, it is possible to add a surfactant to the liquid with the stacked sheets and / or to apply a surfactant or wetting agent to the fine spunbonded fibers by themselves prior to the addition of liquid thereto. Wetting agents or surfactants can be applied topically to fibers spun-bonded or internally before extrusion. By way of example only, wetting agents and methods for applying same to non-wovens are described in U.S. Patent Nos. 3,973,068 issued to Weber et al., 4,328,279 issued to Meither et al., 4,923,914 issued. Nohr et al., 4,578,414 granted to Sawyer and others, 4,920,168 granted to Nohr and others, 5,656,191 granted to Nohr and others, and 5,814, 567 granted to Yahiaoui and others; The complete contents of the aforementioned patents are incorporated herein by reference. As used herein the term "wetting agent" refers to any chemical composition or compound that makes a fiber surface exhibit increased hydrophilic characteristics.

TESTS Stress Resistance: Stress resistance or peak load measures the maximum load (grams force) before the sample breaks. A sample of 10.2 centimeters by 15.2 centimeters is placed in a rubber-covered clamp of 2.5 centimeters by 2.5 centimeters and in a rubber-covered clamp of 2.5 centimeters by 5.1 centimeters (with the longest dimension being perpendicular to the load) so that The direction of the machine (for example the direction in which the fabric is made) is parallel with the load. The sample is placed on the clamps so that there is a measurement length of 7.6 centimeters. The test can be carried out with an Instron 1130 voltage tester (available from Instron Corporation of Canton, MA) and uses a crosshead speed of 30.5 centimeters / minute and a load cell of 4.5 kilograms. The load to the break is reported in grams. The resistance to normalized stress is calculated by dividing the tensile strength by the basis weight (in grams per square meter) and reported in g / g / square meter.

Melt Flow Rate: The melt flow rate (MFR) determines the amount of polymer that flows through an opening at a fixed temperature and pressure and is reported in polymer grams for 10 minutes. The melt flow rate (MFR) can be determined before the polymer is melt processed according to ASTM D-278-90b; the specific test conditions (for example the temperature) will vary with the particular polymer as described in the aforementioned test. The test conditions for polypropylene are 230 ° C.

Percent Liquid Release: The percentage of liquid release measures the amount of liquid a sheet releases under a specified load and approximate actual cleaning conditions. A sample of 7.6 centimeters by 17.8 centimeters is cut and the dry weight is measured. The sample is attached to an aluminum block having a mass of 0.45 kilograms. The sample / block set is then weighed.

Seventy-five percent (75%) of the liquid capacity of the samples is added directly to the fabric, allowing it to be distributed throughout the sample for one minute and the sample / block set is again weighed. The liquid in total grams added to the sample is obtained by the difference of the dry weight of the block / sample set and the wet weight of the block / sample set. The block / sample set is then pulled 142 centimeters (distance) along an upper surface of a smooth dry bench (with the fabric facing the top of the bench). The sample / block set is again heavy. The top of the bench is dried and the sample / block set is pulled through the surface the second time and the set Sample / block is again heavy and registered. Additional passes through a dry bench top are carried out until the cloth dries or until it shows no additional change. The amount of liquid released for each pass is obtained by the difference of the weight of the sample / block assembly before the pass and the weight of the sample / block assembly after the pass. The percentage of liquid released for each pass can be calculated as follows: percent liquid release = (grams liquid released H-total liquid grams) x 100. The initial liquid release is that released on the first pass.

Taber Abrasion Resistance: Taber Abrasion Resistance measures the abrasion resistance in terms of fabric destruction produced by a controlled rotating rubbing action. Abrasion resistance measurements can be measured according to method 5306, of standard federal test methods No. 191A, except as noted otherwise here. Only a single wheel is used to scratch the sample. A sample of 12.7 by 12.7 centimeters is attached to the sample platform of a Taber standard eroder (model No. 504 with model No. E-140-15 for sample support) having a rubber wheel (No. H-18) ) on the scorching head and a counterweight of 500 grams on each arm. The loss in breaking strength is not used as the criterion for determining the abrasion resistance. The results are obtained and reported in abrasion cycles to the fault where the failure is considered to occur at that point where the hole of 1.25 centimeters inside the fabric is produced.

Average Pore Size: The average pore size can be determined using an automated capillary flow meter PMI (model CFP1100ATXLH).

EXAMPLE Example 1: Yarn-bonded fiber fabric was produced in accordance with known spin-bonding processes such as those described in U.S. Patent No. 3,802,817 issued to Matsuki et al., Using a polypropylene polymer of high melt flow rate (available from Exxon Chemical Company under the trade name ACHIEVE and the designation Exxon-3915, having a melt flow rate of 50 and a polydispersity number of 2). The fabric bonded with fine fiber yarn has an average fiber size of about 11 microns. The fine spunbonded fibers were knitted together with a bonded area of about 17% of the surface area of the fabric. Twenty circular sheets having a diameter of 5 centimeters were cut from the bonded fiber cloth with bound yarn, weighed and then overlaid with one another (unfolded) to form a pile. Approximately 6.6 grams of liquid (75% capacity of the stacked sheets) were added to the stack and allowed to equilibrate through the stack. The liquid comprised 99% by volume of water and 1% by volume of surfactant (sodium dioctyl sulfosuccinate). The individual leaves were removed from the pile and the wet weight was recorded. The leaves were returned to the pile and then the container was sealed and stored at room temperature for 30 days. After having been stored for 30 days, the wet weight of the leaves was obtained (correction is made for the liquid left on the scale in the previous weighing). The weight of dry leaf, the weight of wet leaf in zero days and the weight of wet leaf at 30 days is shown in the graph of figure 4. The graph shows that fiber sheets joined with fine yarn experience little liquid migration over time and provide a uniform moisture stack of pre-moistened cleaning cloths.

Even though several patents and other reference materials have been incorporated herein by this mention, to the extent that it finds any inconsistency between the embodied material and that of the written specification, the written specification will control. Furthermore, even though the invention has been described in detail with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various alterations, modifications and other changes to the invention may be made without departing from the spirit and scope of the invention. present invention. It is therefore intended that the claims cover or cover all those modifications, alterations and / or changes. In addition, as used herein, the term "comprises" or "comprising" is inclusive or open ended and does not exclude additional non-recited elements, compositional components or method steps. Therefore, the term "comprising" embraces the more restrictive terms "consisting essentially of" and "consisting of".

Claims (20)

R E I V I N D I C A C I O N S

1. A liquid delivery system comprising: a sealable container; stacked sheets having at least 10 layers, said sheets comprise non-woven fabrics of spunbonded fiber having a basis weight of at least about 15 grams per square meter and a tensile strength greater than 0.13 kilograms per gram per square meter, and wherein said fibers joined with yarn have an average fiber diameter of less than 18 microns; Y the liquid distributed through said stacked sheets and wherein said sheets have an initial liquid release of at least about 17%.

2. The liquid delivery system as claimed in clause 1, characterized in that said sheets comprise a non-woven fabric joined with a pattern of fibers joined with yarn.

3. The liquid delivery system as claimed in clause 1, characterized in that said sheets comprise a knitted non-woven fabric joined with knitted fibers and wherein the joined area comprises between about 5% and about 30% of the surface area of said leaves.

4. The liquid delivery system as claimed in clause 1, characterized in that said liquid is distributed substantially uniformly through said battery.

5. The liquid delivery system as claimed in clause 4, characterized in that said sheets have a Taber resistance of at least 50 cycles.

6. The liquid delivery system as claimed in clause 4, characterized in that said sheets contain a moisturizing agent.

7. The liquid delivery system as claimed in clause 5, characterized in that said spunbonded fibers comprise a polyolefin polymer.

8. The liquid delivery system as claimed in clause 5, characterized in that said fibers joined with spinning comprise a propylene polymer.

The liquid delivery system as claimed in clause 8, characterized in that said pile has a height of less than 21 centimeters.

10. The liquid delivery system as claimed in clause 9, characterized in that said sheets have a rough fiber layer on the outer surface of at least one side of said sheet.

11. The liquid delivery system as claimed in clause 1, characterized in that said fabrics of spunbonded fibers comprise fibers having an average fiber diameter of between about 8 and 15 micrometers and a mean pore size of between around 15 and around 35 micrometers.

12. The liquid delivery system as claimed in clause 3, characterized in that said sheets have an initial liquid release of at least 20%.

13. The liquid delivery system as claimed in clause 12, characterized in that said spunbonded fibers comprise a propylene polymer and wherein said sheets have a basis weight of between 15 grams per square meter and 85 grams per square meter .

14. The liquid delivery system as claimed in clause 13, characterized in that said spunbonded fibers have a Taber resistance of at least 65 cycles and a tensile strength of at least 0.21 kilograms per gram per square meter.

15. A liquid delivery system comprising: a sealable container; stacked sheets having a stacked height of less than 21 centimeters and at least 10 layers, said sheets consist essentially of a non-woven fabric of spun-bonded fiber wherein said fibers joined with spinning have an average fiber diameter of less than 18 micrometers and wherein said sheet has a basis weight of at least about 15 grams per square meter; a liquid distributed through said stacked sheets wherein said sheets have a Taber abrasion resistance greater than 50 cycles and an initial liquid release of at least about 17%.

16. The liquid delivery system as claimed in clause 1, characterized in that said sheets comprise a fabric bonded with fiber pattern bonded with propylene polymer yarn having a basis weight of between about 15 grams per square meter and 85 grams per square meter.

17. The liquid delivery system as claimed in clause 16, characterized in that said sheets have a tensile strength greater than 0.18 kilograms gram per square meter.

18. The liquid delivery system as claimed in clause 17, characterized in that said sheets contain a moisturizing agent.

19. The liquid delivery system as claimed in clause 17, characterized in that said sheets have an initial liquid release greater than 20% wherein said liquid is essentially evenly distributed through said stack.

20. The liquid delivery system as claimed in clause 19, characterized in that the spunbonded fibers have an average fiber diameter of between about 8 and 15 microns and an average pore size of between about 15 and about of 35 micrometers. SUMMARY A cleaning system is provided comprising a sealable container box of a saturated stack of fiber cleaning sheets bonded with fine and durable yarn; the cleaning sheets have an average fiber diameter of less than 18 micrometers, a tensile strength of at least 140 g / g / square meter and a basis weight of between about 15 grams per square meter and 85 grams per meter square. The cleaning sheets can be provided in a stacked form and kept within a sealed container wherein the liquid is retained within the individual sheets as well as through the stack over time. The sheets can be subsequently removed from the container and applied to a surface where a high percentage of liquid is released from the sheet on the surface in the initial pass and therefore an improved treatment and / or cleaning of the surface is allowed.