AU2003276208A1

AU2003276208A1 - Wiping article

Info

Publication number: AU2003276208A1
Application number: AU2003276208A
Authority: AU
Inventors: Stefano Giolito; Gianluca Lucchini
Original assignee: Unilever PLC
Current assignee: Unilever PLC
Priority date: 2002-11-25
Filing date: 2003-10-28
Publication date: 2004-06-18
Also published as: ZA200502918B; EP1565098A1; CA2503242A1; JP2006507066A; WO2004047606A1; AR042114A1; BR0315776A

Description

WO 2004/047606 PCT/EP2003/012046 WIPING ARTICLE Technical Field 5 The present invention relates to a wiping article which contains dried surfactant and which can be used when wet or dry for the cleaning or dusting of hard surfaces. Background to the Invention and Prior Art 10 Cleaning sheets impregnated with a surfactant component are disclosed, for example, in EP 353 014 which describes a wiping article suitable for use in cleaning soiled surfaces in the presence of water. The article comprises first and 15 second substrate layers (typically water-permeable sheets of fibrous material such as cellulose) with solid surfactant particles sandwiched between the layers. Within the article at the interface between the substrate layers is a discontinuous covering of heat-sealable material such as 20 polyethylene which bonds the layers together. The covering also provides a partial barrier which shields the surfactant particles from water permeating through the substrate layers, and therefore retards dissolution and leaching of the surfactant when the wiping article is brought into 25 contact with water. The wiping article of EP 353 014 is not suitable for use in the absence of water.

WO 2004/047606 PCT/EP2003/012046 -2 US 6,376,046 describes a detergent-impregnated article comprising a detergent-retaining layer which is formed from bulky hydrophobic material capable of retaining a large quantity of detergent and which is sandwiched between 5 detergent-gradual-releasing layers formed from a fibre aggregate of higher density than the retaining layer. The capillary action of the fibres of the release layers retards detergent release from the retaining layer. The article is designed to be used without water since the impregnated 10 detergent itself contains at least 50% by weight water. A problem with the wiping article of US 6,376,046 is that the impregnated detergent is already pre-diluted with water to a fixed concentration when it is incorporated into the 15 article. For some tough cleaning applications, it may be desirable to use a higher concentration of detergent. The present invention provides a wiping article that is equally suitable for use in the presence or absence of 20 water. Summary of the Invention The present invention provides a wiping article which is 25 suitable for the cleaning or dusting of hard surfaces, the article comprising a laminated substrate having a core layer sandwiched between dusting layers, the core layer comprising an absorbent fibrous matrix entrapping dried surfactant, and the dusting layers comprising a polymeric fibrous web having 30 a capillary structure which permits uptake of water and release of the surfactant when the article is wetted.

WO 2004/047606 PCT/EP2003/012046 -3 When dry, the wiping article of the invention is especially effective for the entrapment and removal of dust and other particulate soil. When wetted, the wiping article of the invention is especially effective for cleaning and 5 degreasing. The wiping article of the invention has a number of advantageous properties. In particular, it provides a significant cost benefit to the manufacturer because it does 10 not require expensive packaging technology, unlike conventional "wet wipes", which will dry out and lose functionality unless maintained in airtight sealed conditions. 15 The wiping article of the invention also provides significant cost benefits to the consumer, because of its dual functionality and the fact that it can be re-used. Flexibility of usage is also improved since in wet cleaning applications the consumer decides the level of water to be 20 applied to the article. Therefore the concentration of available surfactant which is generated by the wetting process can be tailored according to the degree of soiling and nature of the surface to be treated. 25 Detailed Description of the Invention The wiping article of the invention is designed in particular for the cleaning of hard surfaces. By "hard surfaces" is meant those surfaces which are typically found 30 in the household. Examples include furniture surfaces, WO 2004/047606 PCT/EP2003/012046 -4 kitchen worktops, sinks and appliances, bathroom fixtures and fittings, wall and flooring surfaces. The wiping article of the invention comprises a laminated 5 substrate having a core layer sandwiched between dusting layers. The core layer comprises an absorbent fibrous matrix. Preferably the absorbent fibrous matrix is formed from 10 cellulosic fibres, such as pulp and rayon. Wood pulp fibres are most preferred. The dusting layers comprise a polymeric fibrous web having a capillary structure which permits uptake of water and 15 release of the surfactant when the article is wetted. Preferably the polymeric fibrous web is formed from polyolefinic fibres, such as C2-1o polyolefins or copolymers thereof, especially C 2

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4 polyolefins such as polyethylene and polypropylene. Polypropylene fibres are most preferred. 20 Suitable laminated substrates which may be used to form the wiping article of the invention are commercially available and may be formed by many processes such as, for example, meltblowing processes, spunbonding processes, 25 hydroentangling, airlaid and bonded carded web processes. A commercially available example of a suitable laminated substrate which may be used to form the wiping article of the invention is Akena 4SQ ex Orlandi. This is a laminated WO 2004/047606 PCT/EP2003/012046 -5 material with a layer of wood pulp fibres sandwiched between layers of polypropylene fibres. In the wiping article according to the invention, the core 5 layer of the laminated substrate entraps dried surfactant. This may be achieved by a process of impregnating the laminated substrate with a solution of the surfactant in a suitable solvent, followed by heating of the impregnated substrate in order to drive off the solvent and thereby 10 concentrate the surfactant in dried form into the core layer of the laminated substrate. Suitable surfactants to be used in the wiping article according to the invention include any surfactant known to 15 those skilled in the art like nonionic, anionic, cationic, amphoteric and/or zwitterionic surfactants. Preferred surfactants to be used are the amphoteric and/or zwitterionic surfactants. 20 Amine oxides are particularly preferred for use in the wiping article of the invention since they are mild, pH neutral and stable to oxidation. They are also especially effective at cleaning and degreasing when the wiping article is wetted, even when they are incorporated into the wiping 25 article at low levels. Preferably amine oxide is used as the sole surfactant component in the wiping article of the invention.

WO 2004/047606 PCT/EP2003/012046 -6 Suitable amine oxides to be used in the wiping article of the invention may be generally described as those tertiary amine oxides of the formula R 2 R'NO, in which each R is a lower alkyl group, for instance an alkyl group having from 1 5 to 3 carbon atoms, preferably methyl, and R' is a long chain alkyl group, for instance an alkyl group having from 8 to 24 carbon atoms, preferably from 8 to 18 carbon atoms. In the wiping article of the invention, the total content of 10 dried surfactant (preferably amine oxide) suitably ranges from 0.1 to 5%, preferably from 1 to 4%, more preferably from 1.5 to 3% (by weight based on total weight of the wiping article). 15 The wiping article of the invention is preferably supplied to the consumer in the form of a pre-cut roll. This is a convenient and cost-effective product format which enables the consumer to tailor the size and thickness of product used more easily than with a conventional "stack" of wipes 20 which have a predetermined size. The wiping article of the invention can contain other optional ingredients which aid in performance and consumer acceptability. 25 Examples include: preservatives, perfumes, colours and dyes, hygiene agents, and mixtures thereof. The invention will now be illustrated by the following non 30 limiting Example, in which all percentages are by weight based on total weight, unless otherwise indicated.

WO 2004/047606 PCT/EP2003/012046 -7 EXAMPLE A wiping article according to the invention is prepared by spraying an aqueous solution of amine oxide onto a dry 5 substrate having a 3-layer structure with two outer layers of polypropylene "sandwiching" an inner core layer of wood pulp (commercially available as Akena 4 SQ, ex Orlandi). After the substrate has absorbed the aqueous solution of 10 amine oxide homogeneously, it is gently heated between 50 and 90 0 C in a ventilated oven, to allow a.homogeneous evaporation of the water, and a homogeneous dispersion of the dried amine oxide in the substrate. 15 After the water has completely evaporated, the wiping article is ready to be used, and contains approximately 50mg of dried amine oxide per 1.8g of dry substrate. Evaluation of the wiping article showed that it gave 20 excellent dusting performance when dry, as well as cleaning and degreasing performance when wetted with water.

Claims

1. A wiping article which is suitable for the cleaning or dusting of hard surfaces, the article comprising a 5 laminated substrate having a core layer sandwiched between dusting layers, the core layer comprising an absorbent fibrous matrix entrapping dried surfactant, and the dusting layers comprising a polymeric fibrous web having a capillary structure which permits uptake 10 of water and release of the surfactant when the article is wetted.

2. A wiping article according to claim 1, in which the absorbent fibrous matrix of the core layer is formed 15 from cellulosic fibres, preferably wood pulp fibres.

3. A wiping article according to claim 1 or 2, in which the polymeric fibrous web of the dusting layers is formed from polyolefinic fibres, preferably 20 polypropylene fibres.

4. A wiping article according to any of claims 1 to 3, in which the amine oxide is used as the sole surfactant component. 25

5. A wiping article according to any of claims 1 to 4, which is in the form of a pre-cut roll.