TECHNOLOGICAL FIELD

The present disclosure concerns wet wipes suitable for cleaning purposes, specifically for collecting particulate matter from surfaces.

BACKGROUND ART

References considered to be relevant as background to the presently disclosed subject matter are listed below:

- US patent application publication no. 2006/134047

- US patent application publication no. 2007/202768

- US patent application publication no. 2009/236033

- US patent application publication no.2019/2544500

- PCT patent application publication no. W010021911

- PCT patent application publication no. W013070522

- PCT patent application publication no. W017123734

Acknowledgement of the above references herein is not to be inferred as meaning that these are in any way relevant to the patentability of the presently disclosed subject matter.

BACKGROUND

Wet wipes are fabric or cloth pieces, usually for single use, that are typically pre soaked with a cleaning liquid and vastly used for cleaning of various surfaces, e.g. floors, countertops, furniture, etc. Such wipes are often made of fabric and impregnated or soaked by a cleaning solution, such that no rinsing is required after application, making their use a convenient method for maintaining surfaces hygiene. Most wet wipes are suitable for limited absorption of liquids during cleaning (such that they can be used to clean liquid spillage), removal of oily residues by use of one or more surfactants, and also for collecting fine particulate matter, such as dust or fine powders, typically by physical entrapment between the fibers of the wipe.

Cleaning of particulate matter having a relatively large particle size is often problematic, as most wet wipes do not provide sufficient adherence to collect and hold large particles. For this purpose, dry wipes having a tacky surface are often used; however such dry wipes typically cannot be used to clean surfaces by a wet solution as the cleaning solution hampers the adhesive properties. In other words, while wet wipes cannot be utilized for collecting large particulate matter, dry wipes cannot be used for wet cleaning of surfaces.

GENERAL DESCRIPTION

The present disclosure concerns dual purpose wet wipes that permit wet-cleaning of surfaces on the one hand, while also permitting collection of large particulate matter on the other. The wet wipes of this disclosure comprise an adhesive composition that maintains its tackiness although wetted (or being wet), thereby permitting wet-cleaning of surfaces and removal of large particulate matter is a single cleaning operation, without leaving streaks or sticky leftovers on the cleaned surface. The wet wipes utilize an aqueous adhesive composition that is consumer and environmentally friendly.

The wet wipes of this disclosure are designed to permit simultaneous wet-cleaning and collection ( i.e . adherence) of large particulate matter in a single wiping action. Thus, in one of its aspects, the disclosure provides a wet wipe that comprises a fabric substrate impregnated by a liquid composition, the liquid composition comprising at least one polymer material, at least one surfactant and water, the wet wipe being capable of adhering thereto at least 50% of particles having an average particle size of above about 2 mm (millimeters), when used in a single wipe of a surface.

In other words, the wet wipe comprises a liquid composition that is capable of providing wet-cleaning of a surface, while also being tacky enough (at its wet state) to permit capturing of relatively large particles for their removal from the surface. The term tacky or tackiness refers to the capability of the liquid composition to adhere particles thereto; namely, the term refers to the stickiness of the liquid composition. The liquid composition is designed to have a tackiness or stickiness that is sufficient to collect and adhere particles, typically exceeding a size of about 2mm, to the wet wipe. Namely, in addition to collection and adhering of fine particulate matter, such as dust, the wet wipes of this disclosure have a tackiness that enables the wipe to collect and adhere thereto large particles of over 2mm in size.

By another aspect, the disclosure provides a wet wipe that comprises a fabric substrate impregnated by a liquid composition, the liquid composition comprising at least one polymer material, at least one surfactant and water, said at least one polymer material comprises at least one polysaccharide or polysaccharide derivative, the wet wipe being capable of adhering thereto at least 50% of particles having an average particle size of above about 2 mm, when used in a single wipe of a surface.

By some embodiments, the wet wipe is capable of adhering thereto at least 55%, at least 60%, at least 65%, at least 70% or even at least 75% of particles having an average particle size of above about 2 mm and/or a total weight of particles of up to 2 g (grams), when used in a single wipe of a surface.

The wet wipe, by some embodiments, can adhere thereto particles having an average particle size between about 2mm and about 10mm.

The term average particle size refers to refers to the arithmetic mean of measured diameters of the particles in the particulate matter. Where the particles are not spherical, the term means to denote the arithmetic mean of the largest dimension of the particles.

As noted, the liquid composition comprises at least one polymer material and at least one surfactant, in a water medium. The liquid composition is designed to provide adhering of at least 50% of large particles at a single wipe, although comprising a relatively large content of water medium. The liquid composition may be in any suitable form, e.g. solution, dispersion, suspension, emulsion, gel, etc.

The polymer (or polymer material) is a molecule built-up from one or more repetitive units (i.e. monomers) that together form a chain or a macromolecule. The polymer is typically water-soluble or water-dispersible, and can be natural, semi synthetic, or synthetic. The term includes homopolymers, copolymers, such as block, graft, random and alternating copolymers, as well as terpolymers, including derivatives, combinations and blends thereof. The term also includes all geometrical configurations of such structures, including linear, block, graft, random, alternating, branched structures, and combination thereof.

By some embodiments, the at least one polymer material comprises at least one polysaccharide or polysaccharide derivative. The polysaccharide is a polymer built out of monosaccharide ( e.g . simple sugars) building units - i.e. monosaccharide monomers. The polysaccharide may or may not be made of a plurality of identical monomers (such as in the case of dextran) or different monomers (such as in the case of arabinogalactan). The polysaccharide may be natural or synthetic and may be branched or linear. The polysaccharide may be a chemically modified polysaccharide or a semi -synthetic polysaccharide.

By some embodiments, the polysaccharide can be selected from guar gum and guar gum derivatives, starch and starch derivatives, pectin and pectin derivatives, carrageenan and carrageenan derivatives, cellulose and cellulose derivatives, agar and agar derivatives, chitin and chitin derivatives, xanthan gum and xanthan gum derivatives, konjac gum and konjac gum derivatives, glycogen and glycogen derivatives, galactogen and galactogen derivatives, inulin and inulin derivatives, arabinoxylan and arabinoxylan derivatives, alginate and alginate derivatives, locust bean gum and locust bean gum derivatives, acacia gum and acacia gum derivatives, gellan gum and gellan gum derivatives, and any mixture thereof.

Derivative is meant to denote, in the context of the present disclosure, a chemically modified polysaccharide derived from a parent polysaccharide that differs from the parent polysaccharide by one or more elements, substituents and/or functional groups such that the derivative has the same or similar properties/activities as the parent polysaccharide, as defined herein.

By some embodiments, the polysaccharide can be selected from hydroxypropyl guar, acacia gum, xanthan gum, and any combination thereof. By other embodiments, the polysaccharide is hydroxypropyl guar.

By other embodiments, the polymer material comprises at least one polysaccharide or polysaccharide derivative and a polyacrylate. The polyacrylate is a polymer made of acrylic ester monomers and their derivatives. The polyacrylate, by some embodiments, can be selected from poly(methacrylate) (PMA), poly(methyl methacrylate) (PMMA), poly(ethyl methacrylate) (PEMA), poly-hema-poly(2- hydroxy ethyl methacrylate), sodium polyacrylates and any combination thereof. By other embodiments, the polymer is sodium polyacrylate.

By some embodiments, the at least one polymer material can comprise a mixture of at least one polysaccharide or polysaccharide derivative and at least one polyacrylate. By other embodiments, the at least one polymer material can comprise a synergistic mixture of at least one polysaccharide or polysaccharide derivative and at least one polyacrylate.

The weight ratio (wt/wt) between said at least one polysaccharide or polysaccharide derivative and said at least one polyacrylate in the liquid composition can, by some embodiments, be between about 10:1 and about 5:1. By some embodiments, the polysaccharide or polysaccharide derivative is present in the liquid composition in excess with respect to the polyacrylate. In other embodiments, the weight ratio (wt/wt) between said at least one polysaccharide or polysaccharide derivative and said at least one polyacrylate in the liquid composition can be between about 10:1 and 5:1, about 10:1 and 6:1, or even about 10: and 7:1. In some other embodiments, the weight ratio can be 10:1, 9:1, 8:1, 7:1, 6:1, 5:1 and any ratio therebetween.

The liquid composition can contain said at least one polymer material in an amount of between about 0.01 wt% and about 10 wt%.

The liquid composition also comprises at least one surfactant, as noted above. The surfactant is a molecule having one or more hydrophobic chains (or "tails") and a hydrophilic end (or “head”), and is capable of reduce surface tension of water enabling it to spread on and wet surfaces. Due to their structure, surfactants tend to self-assemble into structures when added into water, such as spherical micelles, with the hydrophilic heads facing outwards and the hydrophobic tails facing inwards. Such structures enable surfactants to be used for cleaning, as oily or greasy substances can be dissolved or solubilized within the hydrophobic core of the micelle, thereby isolating and removing oily substances from the surface during wiping and entrapping them within the hydrophobic cores of the micelles.

The at least one surfactant can be nonionic, anionic, cationic, amphoteric or any mixture thereof. By some embodiments, the at least one surfactant is selected from alkyl glucoside surfactants, alkylammonium propionate surfactants, polysorbates, betaines, sulfosuccinates, polyether siloxanes, quaternary amines, alcohol ethoxylates, and any mixture thereof.

By other embodiments, the at least one surfactant is one or more alkyl glucoside surfactants, selected from caprylyl glucoside, hexyl glucoside, caprylyl glucoside, decyl glucoside, undecyl glucoside, C 12-14 alkyl polyglucoside, lauryl glucoside, sodium lauriminodipropionate, sodium cocopropylenediamine propionate, decyl propionate, disodium cocoamphodipropionate, polysorbate 20 (polyoxyethylene (20) sorbitan monolaurate), polysorbate 40 (polyoxyethylene (40) sorbitan monopalmitate), polysorbate 60 (polyoxyethylene (60) sorbitan monostearate), polysorbate 80 (polyoxyethylene (80) sorbitan monooleate), cocoamidopropyl betaine, coco-betaine, lauryl betaine, myristyl betaine, oleyl betaine, laurimidopropyl hydroxyl betaine, soyamidopropyl betaine, and any mixture or combination thereof.

By further embodiments, the surfactant can be selected from caprylyl glucoside, capryl glucoside, sodium lauriminodipropionate, and polysorbate 20.

The liquid composition, by an embodiment, can contain said at least one surfactant in an amount of between about 0.01 wt% and about 10 wt%.

The liquid composition comprises water as a carrier medium, e.g. at least about 80 wt% water.

The liquid composition can further comprise one or more functional additives, such as auxiliary surfactants, co- surfactants, fragrances, dyes, antimicrobial agents, preservatives, pH and buffering agents, chelating agents, skin conditioning agents, polishing agents and any mixture thereof.

It is of note that, according to some embodiments, the liquid composition is substantially devoid of volatile organic compounds (VOCs), i.e. comprising no more than 1 wt% of VOCs, at times no more than 0.5 wt%, no more than 0.25 wt% or even not more than 0.1 wt% VOCs; by other embodiments, the liquid composition is entirely devoid of VOCs. Unlike many wet wipes that make use of VOCs, such as volatile alcohols or solvents, the wet wipes of this disclosure are user and environmentally friendly.

Further, as the wet wipes of this disclosure can be packed in bulk packaging, the liquid composition is designed to be sufficiently tacky to permit collecting large particulate matter on the one hand, however preventing or minimizing adherence of one wipe to another on the other hand.

The wet wipe, as noted, comprises a fabric substrate, which is impregnated with the liquid composition. A measure often used to indicate the content of liquid in a wet wipe is the wetting ratio. The wetting ratio is the ratio between the weight of liquid applied on the fabric and the weight of the fabric itself. In some embodiments, the fabric substrate is impregnated by the liquid composition at a wetting ratio of about 2 to about 3, for example between about 2.5 and about 2.8. The fabric substrate can be made of natural fibers, semi-synthetic fibers, synthetic fibers, or any combination thereof. According to some embodiments, the fabric can be made of polyester, polyethylene, polypropylene, cotton, viscose, nylon, pulp, silk, etc. and combinations thereof.

The fabric may be woven or nonwoven, and can be a single ply or multi-ply fabric produced by any suitable production method known to a person of skill.

According to some embodiments, the fabric is a nonwoven fabric.

While the wet wipes of this disclosure, as noted, utilize the tackiness of the liquid composition to collect and remove large particulate matter off surfaces, some additional physical entrapment of the particulate matter can be afforded by the fabric itself. Thus, by some embodiments, the fabric substrate is an aperture nonwoven fabric, having holes or pores that permit physical entrapment of particulate matter during wiping of the surface. The apertured nonwoven fabric can have any suitable aperture size, for example between about 8 mesh and about 25 mesh (e.g. 8, 10, 13, 15 18, 22 or 25 mesh).

The fabric substrate can have any suitable specific weight, for example, between about 80 and about 120 g/m ²

The fabric may be textured or non-textured, patterned or non-patterned, embossed or non-embossed, and can be of any shape or size.

As the wet wipes of this disclosure comprise a liquid composition which is predominantly water-based and due to the selection of polymeric and surfactant components, the wet wipes can be used to clean any surface, typically hard surfaces such as surfaces made of plastic, wood, stainless steel, Teflon®, vinyl, glass, ceramic, etc., without leaving any sticky residues on the surface during and after cleaning and without leaving streak marks.

By another aspect, this disclosure provides a liquid composition for applying onto a fabric substrate, e.g. for obtaining the wet wipes of this disclosure. The composition can comprise between about 0.01 wt% and about 10wt% of at least one polymer material, between about 0.01 wt% and about 10wt% of at least one surfactant and at least about 80 wt% water, said at least one polymer material comprises at least one polysaccharide or polysaccharide derivative, the liquid composition configured to permit the wet wipe to adhering thereto at least 50% of particles having an average particle size of above about 2 mm. A further aspect of this disclosure provides a method for producing a wet wipe as described herein, the method comprises impregnating a fabric substrate with a liquid composition comprising at least one polymer material, at least one surfactant and water, said at least one polymer material comprises at least one polysaccharide or polysaccharide derivative, thereby obtaining said wet wipe.

According to some embodiments, the fabric substrate is impregnated by the liquid composition at a wetting ratio of about 2 to about 3.

Impregnation refers to soaking or saturating the fabric substrate with the liquid composition. Impregnation can be carried out by any suitable technique, such as spraying, dipping, soaking, coating, dripping, washing, etc.

The method may further comprise a step of preparing the liquid composition before applying it onto the fabric. Preparation of the composition may comprise mixing the at least one polymer and at least one surfactant to form a pre-mix, and then mixing the pre-mix with water to form the liquid composition. Alternatively, the liquid composition may be prepared by mixing the polymer(s) and surfactant(s) with water to obtain the liquid composition. The method may further comprise adding one or more additives into the liquid composition to obtain one or more additional properties (e.g. antimicrobial materials, preservatives, fragrances, colorants, emollients, etc.).

Another aspect of this disclosure provides a dispenser of wet wipes, comprising a dispenser body holding a plurality of wet wipes disclosed herein. The dispenser body may hold a plurality of wet wipes that are arranged within the dispenser to permit extraction of a single wipe at a time from the dispenser by the user. For example, the wipes can be stacked one over the other, can be C-folded to permit pop-up dispensing, can be rolled into a roll of consecutive wipes that can be tear-separated or perforation-separated, etc.

The dispenser may be of any shape and size, can be rigid, semi-rigid, pliable or flexible. The dispenser can be configured to be fixated to a defined location or a hard surface (i.e. on a wall or a furniture item), or can be portable. By some embodiments, the dispenser is configured for consecutive extraction of single wipes therefrom, for example a dispenser that comprises separation means of one wipe from a next-in-line wipe. The dispenser can be, and is preferably, re-closable or re-sealable as to maintain the wet wipes under wet conditions. By another aspect, there is provided an individual wet wipe package comprising a wet wipe as described herein, sealed within a user-breakable or user-rupturable packaging. Such wet wipe package permits packaging and utilization of single wet wipes, for example a flexible sachet or envelope, that can be easily carried by the user for various cleaning-requiring scenarios. A multipack containing a plurality of such wet wipe packages is also an aspect of this disclosure.

By a further aspect, there is provided a cleaning tool, for example, a user-held or user-operable cleaning tool, that comprises at least one wet wipe as described herein, detachably attached to one or more receiving surfaces of the cleaning tool. Such a cleaning tool can be a mop, a wiper, a handle held base, a glove, etc ., onto which a wet wipe as described herein can be detachably attached (namely attached in a temporary and/or removable manner). The receiving surface(s) can comprise a wipe attaching arrangement, for example clamps, pins, clips, Velcro® strips, etc ., permitting temporarily attaching the wet wipe to the cleaning tool. Alternatively, the receiving surface can be selected as to permit temporary adhering of the wet wipe via the liquid composition contained in the wet wipe. By some embodiments, the cleaning tool can comprise a handle for user operation of the tool.

Another aspect provides a kit for cleaning of surfaces, the kit comprises at least one cleaning tool that comprises one or more receiving surfaces configured to detachably receive one or more wet wipes, and one or more wet wipes as descried herein.

As used herein, the term about is meant to encompass deviation of ±10% from the specifically mentioned value of a parameter, such as temperature, pressure, concentration, etc.

Whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range. The phrases ranging/ranges between a first indicate number and a second indicate number and "ranging/ranges from" a first indicate number "to" a second indicate number are used herein interchangeably and are meant to include the first and second indicated numbers and all the fractional and integral numerals therebetween. Generally it is noted that the term at least one as applied to any component of a composition according to this disclosure should be read to encompass one or more ( e.g . two, three, four, five, etc.) different occurrences of said component in a composition.

It is appreciated that certain features of this disclosure, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the technology, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination or as suitable in any other described embodiment of this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Figs. 1A-1C are images of a comparative cleaning test with a wet wipe according to an embodiment of this disclosure (left) and a commercial product (right).

Figs. 2A-2B are images of another comparative cleaning test with a wet wipe according to another embodiment of this disclosure (left) and a commercial product (right).

Figs. 3A-3B are images of yet another comparative cleaning test with a wet wipe according to yet another embodiment of this disclosure (left) and a commercial product (right).

DETAILED DESCRIPTION OF EMBODIMENTS

Example 1

A wet wipe according to an embodiment of this disclosure was prepared as follows. A liquid composition was prepared by first dispersing acacia gum and xanthan gum in caprylyl/capryl glucoside surfactant. The blend was mixed for 30 minutes at room temperature. The blend was then added to a mixer with water and mixed for 10 minutes or until the solution became fully homogenous, following by addition of the rest of the ingredients and further mixing for 30 minutes. Table 1 below shows the list of ingredients used in the liquid composition of this example.

The finished liquid composition was impregnated on a non-woven fabric containing 40% viscose fibers and 60% polyester using a wetting ratio of 2.5.

Table 1: Liquid composition for Example 1

Example 2

Preparation of wet wipe

A wet wipe according to another embodiment of this disclosure was prepared as follows. A liquid composition was prepared by first dispersing hydroxypropyl guar and acrylic copolymer in sodium lauriminodipropionate surfactant. The blend was mixed for 30 minutes at room temperature. The blend was then added to a mixer with water and mixed for 10 minutes or until the solution became fully homogenous, following by addition of the rest of the ingredients and further mixing for 30 minutes. Table 2 below shows the list of ingredients used in the liquid composition of this example.

The finished liquid composition was impregnated on a non-woven fabric containing 100% viscose fibers using a wetting ratio of 2.8.

Table 2: Liquid composition for Example 2

Performance test 2-1

The wet wipe of Example 2 was tested to assess the capability of the wipe to remove breadcrumbs from a surface in comparison to a commercial wet wipe (Nicole™ general purpose cleaning wet wipes, including less than 5 wt% surfactants, preservatives and perfume).

Two piles of 2g of breadcrumbs (average size 2-4 mm) were placed on a surface (Fig. 1 A). A wet wipe prepared according to Example 2 was placed over the left pile, and the commercial product was placed over the right pile (Fig. IB), and slightly pressed down, and then lifted. As can be seen in Fig. 1C, the wet wipe according to Example 2 was capable of adhering thereto the majority of the breadcrumbs (75%), while less than 50% of the breadcrumbs were adhered to the commercial product.

Example 3

A wet wipe according to another embodiment of this disclosure was prepared as follows. A liquid composition was prepared by first dispersing hydroxypropyl guar and acrylic copolymer in sodium lauriminodipropionate surfactant. The blend was mixed for 30 minutes at room temperature. The blend was then added to a mixer with water and mixed for 10 minutes or until the solution became fully homogenous, following by addition of the rest of the ingredients and further mixing for 30 minutes. Table 3 below shows the list of ingredients used in the liquid composition of this example.

The finished liquid composition was impregnated on a non-woven fabric containing 50% viscose and 50% polyester fibers using a wetting ratio of 3.

Table 3: Liquid composition for Example 3

Example 4

Preparation of the wet wipe

A wet wipe according to another embodiment of this disclosure was prepared as follows. A liquid composition was prepared by first dispersing hydroxypropyl guar and acrylic copolymer in sodium lauriminodipropionate surfactant and sodium-2- ethylhexyliminodipropionate. The blend was mixed for 30 minutes at room temperature. The blend was then added to a mixer with water and mixed for 10 minutes or until the solution became fully homogenous, following by addition of the rest of the ingredients and further mixing for 30 minutes. Table 4 below shows the list of ingredients used in the liquid composition of this example.

The finished liquid composition was impregnated on a mesh 22 non-woven fabric containing 50% viscose and 50% Polyester fibers using a wetting ratio of 3.

Table 4: Liquid composition for Example 4

Performance test 4-1 The wet wipe of Example 4 was tested to assess the capability of the wipe to remove black lentils from a surface in comparison to the same commercial wet wipe as in Example 2.

Two piles of 2g of black lentils (average size 2-4 mm) were placed on a surface (Fig. 2A). A wet wipe prepared according to Example 4 was placed over the left pile, and the commercial product was placed over the right pile, and slightly pressed down, and then lifted. As can be seen in Fig. 2B, the wet wipe according to Example 4 was capable of adhering thereto the majority of the lentils (85%), while at most 25% of the lentils were adhered to the commercial product.

Performance test 4-2

The wet wipe of Example 4 was tested to assess the capability of the wipe to remove green lentils from a surface in comparison to the same commercial wet wipe as in Example 2.

Two piles of 2g of green lentils (average size 4-7 mm) were placed on a surface (Fig. 3 A). A wet wipe prepared according to Example 4 was placed over the left pile, and the commercial product was placed over the right pile, and slightly pressed down, and then lifted. As can be seen in Fig. 3B, the wet wipe according to Example 4 was capable of adhering thereto the majority of the lentils (95%), while at most 37% of the lentils were adhered to the commercial product.

Comparative Example 1

A wet wipe containing only acrylic copolymer was prepared as Comparative Example 1 according to the composition of Table 5 and then impregnated on a non- woven fabric. Lentils and breadcrumbs pickup tests (such as those in Examples 2 and 4 above) resulted in insufficient particles pick-up, i.e. below 40%.

Table 5: Liquid composition for Comparative Example 1

Comparative Example 2

A wet wipe without polymers was prepared as Comparative Example 2 according to the composition of Table 6 and then impregnated on a non-woven fabric. While the lentils and breadcrumbs pickup tests (such as those in Examples 2 and 4 above) resulted in above 50% pickup, the liquid composition left sticky residues on the user's hands and on the treated surface, as well as a high degree of foaming during production of the formulation due to the high concentration of surfactant that was required in order to obtain the tackiness effect.

Table 6: Liquid composition for Comparative Example 2