IES85072Y1 - An article for use in washing textile articles - Google Patents

Abstract

ABSTRACT An article for use in a washing machine for washing textile items in a liquid is disclosed. The article comprises a porous substrate material supporting a dye scavenging compound; the substrate material being in the form of a bag or sachet or the like. Enclosed therein is a substance such as a powder or the like having properties for assisting in appropriate or advantageous treatment of the textile items in the liquid. The dye scavenging compound is selected from the group consisting of a N-trisubstituted ammonium 2—hydroxy—3—halopropyl compound. The substance could comprise a cleaning agent with or without a binder; a water softening agent; an enzyme, a brightening agent, a sequestering agent or a surfactant (anionic, non-ionic, or cationic) or any combination thereof.

Description

Article for Use in Washing Textile Articles This invention relates to improvements in or relating to an article for removing extraneous dye or dyes from laundry washing applications.

The problem of extraneous dyes in laundry washing applications is Well known and does not required detailed discussion here. Attempts to overcome the presence of such dyes are well known. For example, United States Patent Specification No. US-A-4 380 453 discloses the use of N-trisubstituted ammoniumhydroxyhalopropyl compounds and salts of epoxy propyl ammonium as dye scavenge compounds.

International Patent Specification No. WO-A-97/48789 discloses a method for the production of a dye scavenging substrate and its use. The substrate can be added to a laundry wash and the active ingredient therein (an N—trisubstituted amrnoniumhydroxy-halopropyl compound) causes extraneous dyes in the wash to be preferentially absorbed onto the substrate rather than to other items of clothing in the wash.

It is an object of the present invention to provide an improvement in the use of a substrate material in a laundry application.

The invention, therefore, provides an article for use in Washing textile items in a liquid in, for cxample, a clothes washing machine, the article comprising a porous substrate material supporting a dye scavenging compound; the substrate material being in the form of a bag or sachet or the like having enclosed therein a substance such as a powder or the like having properties for assisting in appropriate or advantageous treatment of the textile items in the liquid.

Preferably, the substrate material comprises a cellulosic material. Preferably, the substrate material has incorporated therein a dye—scavenging compound selected from the group consisting of a N-trisubstituted ammonium 2—hydroxyhalopropyl compound having the general fomiula (IN on m c: ~: to R / X~CH;—CHOH~CH2—N-R Y" + \ R and a salt of epoxy propyl ammonium having the general formula.

R / CH2-CH—CH2—N-R Y’ \ / +\ O R wherein x is a halogen radical, Y is a chloride, bromide, sulphate or sulphonate, and the Rs are the same or different and are methyl, ethyl, butyl or benzyl groups or an hydroxyl substituted derivative thereof. A preferred compound is glycidly methyl-ammonium chloride (GMAC).

The substrate material can comprise a dye scavenging substrate made in accordance with the method disclosed in International Patent Specification No. WO 97/48789. The substrate material can be made into a bag or sachet or the like by folding a suitably sized sheet of the substrate material and securing the sides along their periphery with the substance enclosed therein.

Alternatively, the wall of the bag or sachet may consist of two sheets of substrate material secured together about their periphery with the substance enclosed therein.

Depending on the nature of the substance to be enclosed within the bag, it may be desirable to provide a face of the substrate material with a polymeric material which face eventually comprises the inner wall of the bag or sachet. The polymeric material may be sprayed onto the face of the substrate or otherwise suitably added or applied to it. Where such a polymeric material is used, it will be understood that, to achieve the same effective dye scavenging ability as the substrate material without the polymeric material, the surface area of the substrate material may need to be increased or the composition of the dye scavenging compound as taught in International Patent Specification No. WO 97/48789 may need to be modified. Such modification can be achieved in a variety of techniques. For example, a binder, such as a polyvinyl alcohol can be used in the manufacture of the substrate material.

The percent binder used (by weight) should be of the order of 12% or less (preferably not less than 10%) so as to provide sufficient sites for the dye scavenging material.

The use of a polymeric material provides a number of advantages. Firstly, the presence of the polymeric material on what are effectively opposing faces of the bag or sachet enables the bag to be sealed around the periphery thereof. Secondly, the presence of the polymeric material prevents or substantially reduces the contact between powder in the bag and the dye scavenging compound of the substrate material when the bag or sachet is not in the “in use" condition in a washing machine. Thirdly, the presence of the polymeric material at least initially enables the bag or sachet to float in the in use condition when the powder in the bag is, for example, an oxygen producing compound such as sodium carbonate peroxyhydrate or sodium carbonate or a combination thereof. When the powder comes into contact with the water in the washing machine, oxygen is rapidly produced which is temporarily retained in the bag or sachet which effectively becomes balloon like in character thereby leading to greater buoyancy and improved operating characteristics. It will be appreciated that, once the powder/water reaction has finished, the oxygen thus produced will eventually dissipate and the bag will function as a dye scavenging substrate.

It is desirable that, in making the bag or sachet, certain characteristics are present. Ideally, all of them should be present but this is not essential. These characteristics for the bag or sachet include good scalability, good porosity, good dye pick up, good wash durability and good buoyancy. Good scalability is desirable so that the bag or sachet does not break open or prematurely disintegrate in the washing machine when in use. Good porosity is desired to enable the powder in the bag or sachet to leach out from the bag or sachet in the washing machine when in use. Good wash durability is desirable as the bag or sachet can carry powder of about 30g and be capable of withstanding wash temperatures of up to 95°C. Good buoyancy can improve the effectiveness of the article in use in the washing machine.

The substance within the bag or sachet can be selected from appropriate substances which are suitable for assisting in the appropriate or advantageous treatment of the textile items in the wash. For example the substance could comprise a cleaning agent with or without a binder; a water—softe11ing agent; an enzyme, a brightening agent, a sequestering agent or a surfactant (anionic, non—ionic or cationic) or any combination thereof.

A preferred substance is a bleach additive. Such a bleach additive can be, for example, sodium carbonate peroxyhydrate or sodium carbonate or a combination thereof. A suitable combination is sold under the brand name Oxyper S C B from Solvay Chemicals International SA, Brussels, Belgium.

As disclosed in lntemational Patent Specification No. WO—A—97/48789, the method for the production of the substrate material may comprise the steps of:- (a) providing a ccllulosic substrate; (b) passing the substrate through a bath containing an alkaline solution of an N- trisubstituted ammonium 2-hydroxyhalopropyl compound having the general formula: R / X—CHg—CHOH—CH2—N-R Y’ + \ R or a salt of epoxy propyl ammonium having the general formula: R / CH2-CH—CH2-N-R Y’ \ / + \ O R wherein X is a halogen radical, Y is a chloride, bromide, sulfate or sulfonate, and the R's are methyl, ethyl, butyl or benzyl groups or an hydroxyl substituted derivative thereof; (c) subjecting the substrate to a pressure of between 069-] .37MPa (100-200 psi); (d) heating the substrate to a temperature of between approximately 35°C or 45°C; ix) Us (e) wrapping the substrate in a water impermeable material and rotating the material at a temperature of between 15°C and 100°C for a period of between 1 hour and 12 hours; (t) removing the water impermeable material and passing the substrate through an acid bath; (g) subjecting the substrate to a pressure of between 1.03 - 1.72Mpa (1 50-250 psi); (h) drying the substrate.

The substrate material prior to the incorporation of the dye—scavenging chemical preferably comprises pulp (approximately 68% by weight), viscose (approximately 20% by weight) and a binder (approximately 12% by weight). The dye scavenger formulation preferably comprises glycidyl methyl—ammonium chloride (approximately 7.6% by weight), sodium hydroxide (approximately 3.2% by weight) and water (approximately 89.2% by weight).

In order to provide the polymeric material on one face of the substrate material, a process known as sintering is used. Sintering does not form a continuous coating thus preserving the porosity of the substrate material. This is required so that the substance enclosed within the bar or sachet can come into contact with the liquid when the bag or sachet is in use. The primary purpose of the polymeric material is to enable the bag or sachet to be sealed. The polymeric material could, if desired, be applied to the periphery of the substrate material for enabling the bag or sachet to be sealed but it has been found from a cost perspective that the sintering technique of applying the polymeric power to the entire face of the substrate material rather than a part of the material is preferred. Thus, as an example of the sintering process, a roll of treated non-woven material is unwound into a sintering machine. Villars and Keller of Switzerland produce such a machine. A hopper is fed with thermoplastic polyethylene powder. The thermoplastic powder is available from Schaetti AG. Birgistrasec CH—8304 Wallisellen and is known as Schaetti Fix powder. The powder can be fed onto a shaker roller which scatters the powder evenly onto the web. The web then enters an infrared tunnel at approximately 130°C. This melts the powder onto the web. It is then passed thorough a cooling roller and a nip roller and rewound.

In order to assess the preferred level of polyethylene powder commensurate with the desired scalability, porosity, wash durability, buoyancy and dye pick up, a number of tests was carried out and the following results were obtained.

GSM (g.m 2) 15g 25g 35g Sealability Poor Very good Excellent Porosity Excellent Very good Poor Wash durability 90°C Good Very good Excellent Buoyancy Good Very good Excellent Dye Pick Up Very good Very good Very Poor Note: GSM refers to grams of polyethylene powder per square meter of substrate material.

It will be appreciated that a preferred concentration of polyethylene material is at the weight of around 25g.m'2.

When the substance used is, for example, the bleach additive comprising a combination of sodium carbonate peroxyhydrate and sodium carbonate, a by-product of a chemical reaction between the bleach additive and the substrate material in the form of trimethylamine (TMA) can be generated where the pre-cursor of the GMAC is glycol and propanol rcagens. TMA is detected as having a strong amine-like odour. If it is desired to overcome this problem, a rinse stage may be used in addition to the steps outlined above: A roll of substrate 12% - 18% binder type is treated in a 3rd pass through a padding machine at 50 m per minute. The nip pressure of the rollers is approximately 1 bar (100kPa) +/- 10%. The volume of rinse water used may be between 500 -700 1 for 4140 sq m of substrate and may be applied using a spray f\) 'J‘u bar with a wetting bar. The temperature of the rinse water can be between about 13°C and “C. Subsequently the substrate may be passed through a second padding machine which has several integrated drying steams cans. The speed of the machine may be set at about 45 in per minute. The nip pressure of the rollers may be approximately 1 bar (l00kPa) +/- 10%.

The following example relates to a bag or sachet with GMAC as the dye scavenger.

A l00mg.l" solution of Direct Red Dye is made up accurately and used for the following analysis. (The dimensions of the sample bag or sachet are approximately l05.75mm x l l3.81mm containing approximately 30g of powder.) . A single bag or sachet is placed in a 51 beaker and 400ml of water are added. The water is heated to approximately 65°C and the bag is stirred until all the powder has been dissolved. The bag is then removed from the beaker and any excess moisture is removed by wringing it out by hand.

A 200ml aliquot of the dye solution is heated in a 200ml beaker to 65°C.

The bag is placed in the beaker, ensuring that the bag is immersed completely in the dye solution and stirred.

The bag is stirred continuously for a period of not less than 1 minutes or more than 3 minutes after which time the bag is removed.

The temperature of the solution should be maintained at approximately 65°C for the duration of the test.

The solution is then filtered immediately to remove all traces of any loose fibres from the bag.

The resultant solution is tested using a Hach Spectrophotometer for any residual dye content and the result is recorded.

. A pass or fail result is assigned depending on the amount of dye remaining in the solution. 9. Less than or equal to 6mg.l‘I is a pass whereas 7mg.l" or over is deemed to be a fail.

A 200ml aliquot of a 1O0mg.l"1 dye solution contains 20mg of dye. For a pass result each bag should preferably be capable of absorbing 18.8mg of dye or greater, leaving 1.2mg of dye or less in the beaker. (To convert from mg.l" to mg of dye in the 200ml aliquot, divide the Hach result by 5).

It should be noted that the Hach Spectrophotometer is only capable of reading sensitivity of not less than 1mg.l". The fail point is less that about 7mg.l" therefore it is reported that a value of 6mg.l'1 or less is a pass.

The results of the test are illustrated in Figures 1 and 2 attached.

The invention is not limited to the disclosure described herein, which may be modified or varied without departing from the scope of the invention.

Claims (5)

Claims

1. An article for use in washing textile items in a liquid, the article comprising a porous substrate material, optionally a cellulosic material, supporting a dye scavenging 5 compound; the substrate material being in the form of a bag or sachet or the like having enclosed therein a substance such as a powder or the like having properties for assisting in appropriate or advantageous treatment of the textile items in the liquid and, further optionally, wherein the substrate material has incorporated therein a dye scavenging compound selected from the group consisting of a N-trisubstituted ammonium 2- 10 hydroxy—3-halopropyl compound having the general formula R / I5 X—CHg~CHOH—CH2—N-R Y" + \ R and a salt of epoxy propyl ammonium having the general formula 20 R / CH2—CH-CH2-N-R Y' \ / +\ 25 O R wherein x is a halogen radical, Y is a chloride, bromide, sulphate or sulphonate, and the Rs are the same or different and are methyl, ethyl, butyl or benzyl groups or an hydroxyl substituted derivative thereof; and, still further optionally, wherein the compound is glycidly 30 methyl—ammonium chloride (GMAC).

2. An article as claimed in claim 1 wherein the bag or sachet comprises (a) a suitably sized sheet of the substrate material folded and secured around the periphery thereof with the substance enclosed therein; or P85l45IE0l /June 3, 20 (b) two sheets of substrate material secured together about their periphery with the substance enclosed therein.

3. An article as claimed in claim 1 or claim 2 wherein a face of the substrate material, 5 which face comprises the inner wall of the bag or sachet, incorporates a polymeric material and, optionally, wherein the polymeric material is in the form of a binder such as polyvinyl alcohol.

4. An article as claimed in any of claims 1-3 wherein the substance comprises a cleaning 10 agent with or without a binder; a water softening agent; an enzyme, a brightening agent, a sequestering agent or a surfactant (anionic, non ionic, or cationic) or any combination thereof and, optionally, wherein the substance is a bleach additive such as sodium carbonate pcroxyhyorate or sodium carbonate or a combination thereof. 15

5. An article substantially as hereinbefore described.