FIELD OF THE INVENTION

This invention relates to a method of treating carpets and other textiles comprising animal fibres or a mix of synthetic and animal fibres to control the larvae of wool-eating insects and hence to improve resistance to damage caused by insects.

BACKGROUND

Present methods of treating wool and other animal fibres to resist attack by insects involve treating the fibres with conventional insecticides such as synthetic pyrethroids, most commonly permethrin. Although permethrin is highly effective for control of these insects and it has a low mammalian toxicity, there are several disadvantages associated with its use.

Where permethrin is applied using conventional wet-processing techniques, even under the best industrial conditions, small amounts of insect-resist chemical will always be discharged with the exhausted liquors. Permethrin has a broad spectrum of activity and is particularly toxic to aquatic organisms and this in turn has an adverse impact on fish species. Therefore, the presence of permethrin in effluent is highly undesirable environmentally as effluent contaminated with permethrin may directly enter surface waterways or be incompletely removed after sewage or other waste treatment and impact waterways into which the treated liquor is discharged.

The problem is particularly severe in parts of the UK where very strict limits have been set on insecticide levels in effluent. In one particular area (Severn-Trent Water Authority) these controls are so strict that effluent from traditional insect-resist

treatment methods cannot be treated to meet the levels imposed at normal textile-mill dilutions.

In Australasia where legislation is less severe, the problem has been exacerbated by the increased levels of permethrin required to achieve complete protection against permethrin-resistant beetle species. Treatment levels have been duly increased to maintain control of this species. While the application levels have been doubled, the result has been up to a seven fold increase in effluent levels.

Alternative "dry" processing techniques have been developed which essentially produce no liquid effluent and therefore eliminate the problem associated with permethrin discharge. However, this technology is not directly applicable to processors in non-vertical mills and hence the need for an environmentally benign alternative to permethrin remains.

In certain regions of Europe where environmental consciousness is high, consumers are becoming increasingly dissatisfied with products containing pesticides. False reporting by the European media concerning the health-risks associated with permethrin-treated carpeting have increased consumer disaffection with permethrin- based mothproofing agents. An alternative to permethrin is urgently being sought to cater for this growing "green" market.

An object of this invention is to provide a method of treating carpets and other textile products comprising animal fibres or a mix of synthetic fibres and animal fibres using low application levels of a fluorosurfactant compound which effectively controls the larvae of a range of wool pests including moth and beetle species.

A further object of the present invention is to provide an alternative method for treating animal fibres.

A number of insect-resist agents are available which are highly effective in controlling the larvae of Lepidopteran (moth) species, but ineffective against the larvae of Coleopteran (beetle) species. Therefore, yet a further object of this invention is to incorporate effective fluorosurfactant compounds, which themselves offer control of a range of the Coleopteran species but only partial control of a range of wool-eating Lepidopteran species, into a formulation containing a Lepidopteran specific compound thereby achieving protection against the full range of wool-eating pests.

According to one aspect of the present invention, there is provided a method of treating carpet and other textile products comprising animal fibres or a mix of synthetic fibres and animal fibres, the method including applying a formulation to carpet or other textile products, the formulation comprising compounds effective against the larvae of a range of Coleopteran species and a chemical which is effective against the larvae of a range of Lepidopteran species.

The fluorosurfactant compound can offer only partial control of the larvae of a range of Lepidopteran species. The fluorosurfactant can have the following structures: Fluorinated alkyl polyoxethylene alcohol, perfluoro alkyl sulphonante CF3 (CF2>n SO3A; perfluoro alkyl sulphone CF3 (CF2>n SO2 A (n = 0-9, A = structurally compatible residue).

The formulation can be added to the carpet, yarn, loose fibre or other textiles during raw-wool scouring, dyeing, tapescouring, chemsetting or continuous carpet treatment.

The formulation may be applied to the carpet or other textiles using a pad- application, exhaust application, spray application, oiling (spinning lubricant) application or powder application.

According to a second aspect of the present invention, there is provided a method of treating carpets or other textiles, the method including the steps of:

- adding a formulation containing fluorosurfactant to a polymer;

- applying the formulation to the carpet or other textiles; and

- fusing the polymer to the carpet or other textiles.

The formulation can comprise a fluorosurfactant compound which is effective against the larvae of Coleopteran species combined with a chemical which is effective against the larvae of Lepidopteran species.

The polymer can have a low melting temperature. The polymer and formulation can be ground into a fine powder prior to being applied to the carpet or other textiles.

According to a third aspect of the present invention, there is provided a method of treating carpets or other textiles, the method including the steps of:

- incorporating a formulation into a synthetic fibre;

- blending the synthetic fibre with wool fibres; and

- heating the synthetic fibre and the wool fibres so as to fuse the synthetic fibre onto the wool fibres.

The formulation can comprise a fluorosurfactant compound which is effective against the larvae of Coleopteran species combined with a chemical which is effective

against the larvae of Lepidopteran species. The synthetic fibre can be a low melt bicomponent synthetic fibre.

The carpet and other textiles may comprise solely animal fibres or a mix of synthetic and animal fibres.

When applied to animal fibres under typical dyeing conditions, the treatment is substantially fast to light and subsequent wet-treatments.

Further objects and advantages of the invention will become apparent from the following description which is given by way of example only.

Example 1

Plain weave wool fabric was padded with solutions of an amine perfluoroalkyl sulphonate diluted to achieve wet pick ups of 0.002 to 1 .0% of fluorosurfactant on wool weight. These samples were dried at room temperature and discs of 40mm in diameter were randomly cut from the treated fabrics and submitted for bioassay testing against common clothes moth larvae (Tineola bisselliella) according to the procedure outlined in Wools of New Zealand Test Method 25. The results from the tests (as set out below in Table 1 ) indicated that excellent control in terms of high mortality and low wool weight losses were achieved at concentrations of 0.02 % fluorosurfactant.

TABLE 1 . RESULTS FROM TINEOLA BISSELLIELLA SCREENING ASSAYS ON FABRICS.

Treatment level Mean Mean Reduction Visual Pass/ of fluorosurfactant mortality mass in feeding rating fail

(%) loss damage cropping/

(mg) compared to holes* control (%) estimate

Control 1 00.0 57.87 1 D F

(0.002%) 15.0 75.40 0 1 C F

(0.02%) 98.3 08.96 85 1 A P

Control 2 03.5 58.2 - 1 D F

(0.2%) 92.6 05.73 90 1 B P

(1 .0%) 100.0 01 .28 98 1 B P

* Where: 1 = no detectable damage; 2 = very slight visible cropping; 3 = moderate cropping; 4 = very heavy cropping.

A = no detectable damage; B = yarns or fibres partially severed; C = a few small holes, yarn or fibres severed; D = several large holes. ( ) denotes % active compound on wool weight.

Example 2

Samples were prepared similarly to those in Example 1 although concentrations of 0.002, 0.01 , 0.02, 0.1 , 0.2 and 0.5% of an amine perfluoro-alkyl sulphonate formulation were applied to fabrics using a pad-application method. Discs of each fabric and two control fabrics were tested for resistance to attack by the Australian Carpet Beetle larvae (Anthrenocerus australis) as per Wools of New Zealand TM25. The results for the test are given in Table 2 below.

At all rates tested, the fluorosurfactant showed excellent activity against A australis larvae, with complete mortality being achieved at rates between 0.002 and 0.01 %. All samples passed the test for resistance to Anthrenocerus australis larvae.

TABLE 2. RESULTS FROM ANTHRENOCERUS AUSTRALIS SCREENING ASSAYS ON FABRICS.

Treatment Mean Mean Reduction Visual Pass/

(% fluoro¬ mortality mass in feeding rating Fail surfactant (%) loss damage cropping/ on wool (mg) compared to holes * weight) control (%) estimate (average of four replicates)

Control 1 0 31 .1 B3 F

Control 2 0 39.1 - B4 F

0.002 93.1 2.5 94 A1 P

0.01 100 2.5 94 A1 P

0.02 100 2.7 93 A1 P

0.1 100 4.1 90 A1 P

0.2 100 4.0 90 A1 P

0.5 100 3.5 91 A1 P

* Where: 1 = no detectable damage; 2 = very slight visible cropping; 3 = moderate cropping; 4 = very heavy cropping.

A = no detectable damage; B = yarns or fibres partially severed; C = a few small holes, yarn or fibres severed; D = several large holes.

Example 3

Samples were prepared similarly to those in Example 1 although concentrations of 0.005, 0.0025 and 0.005 and 0.02% of perfluoro alkyl sulphonate were applied to

fabrics using a pad-application method. Discs of each fabric and a control fabric were tested for resistance to attack by Anthrenυs Flavipes larvae as per Wools of New Zealand TM25. Results indicated excellent control at levels down to 0.0005% fluorosurfactant.

TABLE 3 - RESULTS FROM ANTHRENUS FLAVIPES SCRREENING ASSAYS ON FABRICS

Treatment Mean Reduction Visual Pass/

(% fluoro¬ mass in feeding rating Fail surfactant loss damage cropping/ or wool (mg) compared to holes * weight) control <%)

0 44.9 4D F

0.0005 3.9 91 1 A P

0.0025 2.8 94 1 A P

0.005 3.6 92 I A P

0.02 1 .2 97 1 A P

* Where: 1 = no detectable damage; 2 = very slight visible cropping; 3 = moderate cropping; 4 = very heavy cropping.

A = no detectable damage; B = yarns or fibres partially severed; C = a few small holes, yarn or fibres severed; D = several large holes. ( ) denotes % active compound on wool weight.

Example 4

A perfluoro alkyl sulphonate was applied to loop pile carpet of the following construction:

Yarn: 600/2 tex. 100 % wool

Pile height: 6mm

Total pile weight: 1000g/m ²

1 /8" gauge by pad and exhaust application methods to a concentration of about 1 % perfluoro alkyl sulphonate on wool weight. For the exhaust application, 1 % perfluoro alkyl sulphonate was applied during (blank) winch dyeing in which the pH was adjusted to 3, the temperature was raised to the boil at a rate of about

1 °C/min and held at the boil for 30 minutes.

For the pad application, 0.9% perfluoro alkyl sulphonate was padded on to the carpet.

The perfluoro alkyl sulphonate treatment on both carpets was tested for fastness to light and shampooing according to Wools of New Zealand TM 28. The results are given in Table 4.

TABLE 4. RESULTS OF FASTNESS DETERMINATIONS ON PERFLUORO ALKYL SULPHONATE TREATED CARPET.

Treatment Light Shampoo fastness fastness (%) (%)

1 % perfluoro alkyl sulphonate, exhaust 100 88

0.9% perfluoro alkyl sulphonate, pad 94 49

The exhaust-treated carpet was subsequently tested for soiling propensity according to IWS TM 267. The results are given in Table 5. Soiling propensity was not affected by a 1 % treatment.

TABLE 5. SOILING RESULTS TO IWS TM 267.

Treatment Colour change Net E from unsoiled from soiled control carpet control E

Control 13.7

Exhaust 1 % perfluoro alkyl sulphonate 13.8 0.1

Example 5

A fluorinated alkyl polyoxethylene ethanol was padded on to a woven 100% wool fabric of 1 86 g/m ² to achieve 1 .0% on weight of wool.

The fabric was submitted for bioassay testing against common clothes moth larvae (Tineola bisselliella) according to the procedure outlined in Wools of New Zealand Test Method 25. The results are given in Table 6.

TABLE 6. RESULTS FROM TINEOLA BISSELLIELLA SCREENING ASSAYS ON FABRICS.

Treatment Mean Mean Reduction Visual Pass/ mortality mass in feeding rating fail

(%) loss damage cropping/

(mg) compared holes * to control estimate (%)

Control 0 44.28 - 1 D F

Fluorinated alkyl polyoxethylene ethanold %) 84.5 2.67 96 1 A P

* Where: 1 = no detectable damage; 2 = very slight visible cropping; 3 = moderate cropping; 4 = very heavy cropping.

A = no detectable damage; B = yarns or fibres partially severed; C = a few small holes, yarn or fibres severed; D = several large holes.

These results show excellent control at a 1 % add-on of the fluorinated alkyl polyoxethylene ethanol product.

It will thus be seen that the present invention provides a method of treating carpets and other textiles made from animal fibres to improve resistance to damage caused by insects.

Where in the foregoing description, reference has been made to integers or components having known equivalents, then such equivalents are herein incorporated as if individually set forth.

Although the invention has been described by way of example and with reference to possible embodiments thereof, it is to be appreciated that improvements and/or modifications may be made thereto without departing from the scope or spirit of the invention as defined in the accompanying claims.