METHOD FOR APPLYING A TREATMENT AGENT TO A SUBSTRATE

Abstract

A method for applying a treatment agent to a substrate, wherein the treatment agent is bound to a solid polymeric particle at a first pH, and wherein the substrate is contacted with the solid polymeric treatment particles under conditions such that the treatment agent is released from the solid polymeric treatment particles.

Claims

1. A method for applying a treatment agent to a substrate using solid polymeric treatment particles, wherein the substrate is a textile or a fibre, said method comprising: a) providing solid polymeric treatment particles obtainable by at least partially coating solid polymeric particles with the treatment agent in the presence of an aqueous liquid medium, the liquid medium having a first pH, wherein: (i) the surface of the solid polymeric particles has a net positive or net negative charge at the first pH; and (ii) the treatment agent has a net positive or net negative charge within its chemical structure at the first pH; wherein the sign of the net charge on the surface of the solid polymeric particles at the first pH is opposite to the sign of the net charge of the treatment agent at the first pH; and b) contacting the substrate with the solid polymeric treatment particles from step a), in an aqueous liquid medium under conditions such that the treatment agent is released from the solid polymeric treatment particles; wherein the treatment agent is released from the solid polymeric treatment particles by contacting the solid polymeric treatment particles with the substrate in an aqueous liquid medium at a second pH at which the net charge on the surface of the solid polymeric particles or the net charge on the treatment agent has changed such that the signs of the net charge on the surface of the solid polymeric particles is the same as the sign of the net charge of the treatment agent or such that there is no net charge on the surface of the solid polymeric treatment particles or no net charge of the treatment agent; or wherein the treatment agent is released from the solid polymeric treatment particles by contacting the solid polymeric treatment particles with the substrate in an aqueous salt solution.

2. A method for applying a treatment agent to a substrate, wherein the substrate is a textile or a fibre, said method comprising providing solid polymeric treatment particles comprising solid polymeric particles and a treatment agent, wherein the treatment agent is ionically bound to the surface of the solid polymeric particles, and contacting said solid polymeric treatment particles with the substrate in an aqueous liquid medium under conditions such that the treatment agent is released from the solid polymeric treatment particles; wherein the treatment agent is released from the solid polymeric treatment particles by changing the pH of the aqueous liquid medium; or wherein the treatment agent is released from the solid polymeric treatment particles by contacting the solid polymeric treatment particles with the substrate in an aqueous salt solution.

3. A method according to claim 2, wherein the solid polymeric treatment particles are obtainable by at least partially coating solid polymeric particles with the treatment agent in the presence of an aqueous liquid medium, the aqueous liquid medium having a first pH, wherein: (i) the surface of the solid polymeric particles has a net positive or net negative charge at the first pH; and (ii) the treatment agent has a net positive or net negative charge within its chemical structure at the first pH; wherein the sign of the net charge on the surface of the solid polymeric particles at the first pH is opposite to the sign of the net charge of the treatment agent at the first pH.

4. A method according to claim 1, wherein the solid polymeric treatment particles are contacted with the substrate with agitation.

5. A method according to claim 1, for laundry and textile washing, treatments, pre-treatments and post-treatments of textiles and fibres, and dishwashing.

6. A method according to claim 1, wherein said liquid medium has a first pH and the treatment agent comprises at least one ionic group at the first pH.

7. A method according to claim 1, wherein the treatment agent is selected from a surfactant, a buffer, a sequestrant, a builder, a dye, a singlet oxygen generator, a bleach compound, a bleach activator, a bleach catalyst, a dispersant, an optical brightener, an antioxidant, an enzyme, a fragrance, a cyclodextrin, an antistatic agent, a UV protector, an antimicrobial agent, a fabric conditioner, an insecticide, an insect-repellant, a flame retardant, a water-repellant, an oxide or a mixture thereof.

8. A method according to claim 1, wherein the solid polymeric particles have (i) an average mass of from about 1 mg to about 1000 mg; and/or (ii) an average volume in the range of from about 5 to about 500 mm.sup.3; and/or (iii) an average surface area of from 10 mm.sup.2 to 500 mm.sup.2 per particle; and/or (iv) an average particle size of from 1 mm to 20 mm, more preferably from 1 mm to 10 mm.

9. A method according to claim 1, wherein the solid polymeric particles comprise or consist of a polyalkene, a polyamide, a polyester or a polyurethane,

10. A method according to claim 9, wherein the solid polymeric particles comprise or consist of a polyamide.

11. A method according to claim 10, wherein the solid polymeric particles comprise or consist of a polyamide selected from nylon 6 or nylon 6,6.

12. A method according to claim 10, wherein the solid polymeric particles are activated with an acid, a base or an oxidising agent or a combination thereof.

13. A method according to claim 12, wherein the wherein the solid polymeric particles are activated with hydrochloric acid having a molar strength of from 2.0 to 5 M.

14. A method according to claim 1, wherein the solid polymeric particles have an isoelectric point in the range of from pH 3 to pH 7, more preferably in the range of from pH 4 to pH 6, more preferably from pH 5 to pH 6.

15. A method according to claim 1 any one of the preceding claims, wherein the pH of said liquid medium having a first pH is at least 1 pH unit above or 1 pH unit below the isoelectric point of the solid polymeric particles and more preferably at least 2 pH units above or 2 pH units below the isoelectric point of the solid polymeric particles.

16. A method according to claim 1, wherein the isoelectric point of the solid polymeric particles is from 4 to 6 or from 4.5 to 6.5; and the pH of said liquid medium having a first pH is from 7 to 14 or from 1 to 5; provided that the isoelectric point is not the same as the first pH.

17. A method according to claim 1, wherein the treatment agent is released from the solid polymeric treatment particles by contacting the solid polymeric treatment particles with the substrate in an aqueous liquid medium at a second pH at which the net charge on the surface of the solid polymeric particles or the net charge on the treatment agent has changed such that the signs of the net charge on the surface of the solid polymeric particles is the same as the sign of the net charge of the treatment agent or such that there is no net charge on the surface of the solid polymeric treatment particles or no net charge of the treatment agent.

18. A method according to claim 17, wherein the first and second pH are selected such that: A) the first pH is from 7 to 14; more preferably from 8 to 12; and the second pH is from 1 to 5, more preferably from 2 to 5; or B) the first pH is from 1 to 5, more preferably from 2 to 5 and the second pH is from 7 to 14; more preferably from 8 to 12.

19. A method according to claim 1, wherein the treatment agent is released from the solid polymeric treatment particles by contacting the solid polymeric treatment particles with the substrate in an aqueous salt solution.

20. A method according to claim 1, wherein the solid polymeric treatment particles are contacted with the substrate at a temperature of from 20 C. to 90 C. and more preferably at a temperature of from 20 C. to 60 C.

21. A method according to claim 1, wherein the solid polymeric treatment particles are contacted with the substrate for a duration of from 1 minute to 3 hours and more preferably for a duration of from 5 minutes to 1.5 hours.

22. A method according to claim 1, wherein the solid polymeric treatment particles are contacted with the substrate in the presence of a surfactant.

23. A method according to claim 1, wherein the solid polymeric treatment particles are contacted with the substrate in a more dilute concentration than is used for the preparation of the solid polymeric treatment particles.

24. A method according to claim 1 further comprising the following steps c), d) and e): c) separating the solid polymeric particles from the substrate and the aqueous liquid medium; d) optionally cleaning the solid polymeric particles to remove any residual treatment agent; e) re-using the solid polymeric particles in a method for applying a treatment agent to a fresh substrate as defined above.

25. A method according to claim 1, wherein the solid polymeric treatment particles may be contacted with the substrate using an apparatus which comprises: 1. a housing; 2. a rotatable drum; 3. a motor configured so as to be capable of rotating the rotatable drum; 4. a pump for transporting the solid polymeric treatment particles into said drum; and 5. a sump for collecting the solid polymeric treatment particles once the treatment is complete.

26. (canceled)

27. A method according to claim 1, wherein unused treatment agent which has not been successfully been applied to the substrate is recovered.

28. (canceled)

29. A method according to claim 1, wherein the treatment agent is released from the solid polymeric treatment particles by contacting the solid polymeric treatment particles with the substrate in an aqueous liquid medium at a second pH at which the net charge on the surface of the solid polymeric particles or the net charge on the treatment agent has changed such that the signs of the of the net charge on the surface of the solid polymeric particles is the same as the sign of the net charge of the treatment agent or such that there is no net charge on the surface of the solid polymeric treatment particles or no net charge of the treatment agent, and wherein: i. the solid polymeric particles comprise or consist of a polyamide; ii. the solid polymeric particles have an isoelectric point at a pH of from 4 to 6; iii. the solid polymeric particles carry both cation-forming and anion-forming groups; iv. the substrate comprises or consists of a fibre (more preferably the substrate comprises or consists of a textile); v. the first and second pH are selected such that: A) the first pH is from 7 to 14; more preferably from 8 to 12; and the second pH is from 1 to 5, more preferably from 2 to 5; or B) the first pH is from 1 to 5, more preferably from 2 to 5 and the second pH is from 7 to 14; more preferably from 8 to 12. vi. the treatment agent has one or more ionic groups.

30-34. (canceled)

Description

EXAMPLES

Method of Hydrolysis, Adsorption & Desorption:

Softened Water

[0160] All the water used in the examples below was softened using a standard water softener with an ion exchange column which was replenished daily using NaCl. This controls the Ca level to <5 ppm and the Mg level to <5 ppm.

Equipment

[0161] A Konica Minolta Spectrophtometer CM-3600A with SpectraMagic NX Colour Data Software CM-S100w, Professional/Lite Ver2.2, as used to measure transmittance spectra and colour difference.

[0162] pH measurements were made using the VWRpH100L pH meter which was calibrated using the standard buffers also supplied by VWR with the pH meter at pH 4, pH 7 and pH 10.

Hydrolysis of the Nylon 6 Particles

[0163] 200 g of pure nylon particles (average diameter 4.3 mm, average surface area 58 mm.sup.2supplied by BASF, Ludwigshafen, Germany) were hydrolysed in a beaker using 200 mL, 3.5 M hydrochloric acid (diluted from 37% HCl, VWR Chemicals, UK) for 60 minutes at room temperature (20 C.) stirring the particles to ensure even surface exposure to the acid using a mechanical stirrer with a PTFE paddle. The hydrolysed nylon polymer particles were isolated from the HCI and buffered using acetic acid to pH 3.5 before being dried in a fume cupboard overnight at ambient temperature (20 C.). The dried particles were then rinsed with softened water before being used in the adsorption experiments as described in the following examples.

Hydrolysis of Reactive Red 120 (RR120)

[0164] Hydrolysis of Reactive Red 120 was carried out by adding Reactive Red 120 (supplied by Sigma-Aldrich) (1 g, 710.sup.4 M) to 80 mL of softened water with the pH adjusted to alkaline conditions by the addition of sodium carbonate until the pH was above pH 11 (at 80 C., pH 11.5) for 2 hours to ensure all of the dye's reactive component, mono-chlorotriazine, was converted to hydroxytriazine. The end of the reaction was apparent when the pH no longer reduced. The hydrolysed RR120 was then isolated as a solid.

Example 1

Adsorption of Hydrolysed Reactive Red 120

[0165] ##STR00001##

Adsorption

[0166] Hydrolysed nylon 6 particles (50g) and unhydrolysed nylon particles (50g) were treated with 0.1 M HCl (VWR Chemicals, UK) at pH 2 for 30 minutes. Hydrolysed Reactive Red 120 (0.1 g, 710.sup.5 M) was added, separately, to a solution containing softened water (30 mL) and 20 g of each of the nylon polymer particles (hydrolysed and unhydrolysed) and then left to adsorb the dye overnight in at 4 C. For each sample, the particles were separated and analysed using a CM-3600A spectrophotometer (Konica Minolta, UK) in a glass Quartz cuvette (Konica Minolta, UK; 1.3 cm width3.8 cm length5 cm height) at 540 nm.

Desorption

[0167] The acid hydrolysed nylon 6 particles and unhydrolysed nylon particles on which hydrolysed RR120 dye had been absorbed were stirred in a beaker filled with 150 mL of soft water adjusted to pH 11 with sodium carbonate. 0.1 ml of Sodium dodecylbenzene sulphonate (SDBS; 30%, Univar Limited, UK) was added and the mixture was stirred at 60 C. for 30 minutes. For each sample, the particles were separated and analysed at 540 nm as described above.

Results

[0168] Table 1 displays the results for the dye desorption from the polymer particle surface using Reactive Red. In Table 1 the lower the value of L* the more dye is adsorbed to the particle.

TABLE-US-00001 TABLE 1 L* data for adsorption and desorption of hydrolysed Reactive Red 120 Nylon 6 particle type L* Nylon 6 particles (no dye adsorbed) 74.2 Unhydrolysed particles after adsorption 64.2 of hydrolysed RR120 Unhydrolysed particles after desorption 72.4 of hydrolysed RR120 Hydrolysed particles with hydrolysed 39.7 RR120 adsorbed Hydrolysed particles after desorption 51.8 hydrolysed of RR120

[0169] From these results it is clear that the anionic dye hydrolysed Reactive Red 120 is being bound at acidic pH and released at alkaline pH and the degree of binding of the dye is much greater when the hydrolysed nylon particles are used.

Example 2

Adsorption/Desorption of Methylene Blue (MB)

[0170] ##STR00002##

Adsorption

[0171] Hydrolysed nylon 6 particles (50 g) and unhydrolysed nylon 6 particles (50 g) were treated with sodium hydroxide (VWR Chemicals, UK) at pH 12 for 30 minutes and then buffered with sodium carbonate to pH 12. Methylene Blue dye (0.04 g Sigma, UK) was then added to 800 mL of soft water at pH 7. In two separate experiments, the NaOH treated hydrolysed and unhydrolysed particles were left in the Methylene Blue solution at 4 C. overnight to adsorb the dye. For each sample, the particles were separated and then analysed using a CM-3600A spectrophotometer (Konica Minolta, UK) in a glass Quartz cuvette (Konica Minolta, UK; 1.3 cm width3.8 cm length5 cm height) at 670 nm.

Desorption

[0172] The Methylene Blue dye was desorbed from the hydrolysed and unhydrolysed particles by washing with soft water at pH 3.5 and 40 C. in a beaker for 30 minutes. For each sample, the particles were separated and then analysed at 670 nm as described above. The results are shown in Table 2.

TABLE-US-00002 TABLE 2: L* data for adsorption and desorption of Methylene Blue Nylon 6 particle type L* Pure nylon 6 particles 74.2 Unhydrolysed particles with MB adsorbed 63.8 Unhydrolysed particles after desorption of MB 71.6 Hydrolysed particles with MB adsorbed 36.5 Hydrolysed particles after MB desorption 53.7

[0173] From these results, it is clear that the cationic dye Methylene Blue is being bound at alkali pH and released at acid pH and the degree of binding of the dye is much greater when the hydrolysed nylon particles are used.

Example 3

Washing Machine Experiments in the Beko WM5120W Automatic Washing Machine Front Loader

Adsorption

[0174] Approximately 3 Kg of nylon 6 particles were hydrolysed with 11 M sodium hydroxide (NaOH, VWR Chemicals, UK) and then mixed with pH 11 sodium carbonate buffer (Sigma Aldrich, UK). Following this, in two separate experiments, 0.2 g of Methylene Blue dye was added to 4 L of soft water and then mixed with the unhydrolysed particles and NaOH hydrolysed particles before leaving them in the fridge overnight at 4 C. to allow dye adsorption. For each sample, the particles were separated and then analysed using a CM-3600A spectrophotometer (Konica Minolta, UK) in a glass Quartz cuvette (Konica Minolta, UK; 1.3 cm width3.8 cm length5 cm height) at 670 nm.

Beko WM5102W Front Loading Washing Machine 5 kg Scale-Desorption

[0175] The washes were all carried out on the Cotton wash cycle at 40 C. Methylene Blue dye was desorbed from the 3 Kg of negatively charged particles by washing the particles using soft water (at pH 3.5) in a polyester bag and in the washing machine for 1 hour and 45 minutes in the presence of strips of cotton fabric (double scoured bleached cotton interlock fabric from Phoenix Calico Ltd, Huddersfield, UK). All desorption tests were repeated 3 times using the washing machine. Methylene blue pickup by the cotton fabric was analysed using a spectrophotometer, as detailed above, and L* was calculated (see Table 3). Control washes using the nylon 6 particles which had not been hydrolysed with NaOH and particle-free experiments were also undertaken. The results were as shown in Table 3.

TABLE-US-00003 TABLE 3 Dye Pick-up by Cotton fabrics from the hydrolysed, unhydrolysed and No particle experiments with Methylene Blue Dye L* Hydrolysed Unhydrolysed Cotton fabric particles particles No particles Double scoured 97.3 97.3 97.4 bleached cotton interlock fabric wash 1 84.7 91.2 91.3 wash 2 88.2 93.8 92.8 wash 3 90.3 94.9 93.6 Here a lower value of L* indicates a higher level of dye uptake by the cotton fabric corresponding to a higher release of Methylene Blue from the nylon particles.

Example 4

Effect of pH on the Binding of the Anionic Dye Hydrolysed Reactive Red 120

[0176] Low pH solutions (i.e. pH 2, pH 4, pH 6, pH 7) were prepared using soft water (water hardness <5 mg/L) and acetic acid (VWR Chemicals, UK) and high pH solutions (i.e. pH 8, pH 10, pH 12) were prepared using sodium carbonate. The pH of the solutions was confirmed using a pH meter (VWR pH enomenal, pH 1100 L, UK). The pH meter was calibrated before sample measurements were taken. Hydrolysed Reactive Red 120 (0.0005 g) was added to 15 mL of the different pH solutions to obtain a molarity of 0.02 mM. Following this, 1.5 g of hydrolysed (using 3.5 M HCl) nylon particles were added to each pH solution and left in the fridge overnight at 4 C. to allow dye adsorption. For each sample, the particles were separated and the solution was then analysed using a CM-3600A spectrophotometer (Konica Minolta, UK) in a glass Quartz cuvette (Konica Minolta, UK; 1.3 cm width3.8 cm length5 cm height) at 540 nm. The transmittance measured is shown in Table 4, wherein the higher the transmittance, the more dye had bound to the particles and so been removed from solution.

[0177] Thus, clearly the acid hydrolysed nylon 6 particles are selectively binding the negatively charged hydrolysed Reactive Red 120 at low pH.

TABLE-US-00004 TABLE 4 Transmittance against different pH's for Hydrolysed Reactive Red 120 pH range Transmittance/A.U @540 nm pH 2 4 pH 4 3.4 pH 5 3.4 pH 6 3.4 pH 8 3.4 pH 10 3.4 pH 12 1.1

Example 5

Effect of pH on the Binding of the Cationic Dye Methylene Blue

[0178] Low pH solutions (i.e. pH 2, pH 4, pH 6, pH 7) were prepared using softened water and acetic acid and high pH solutions (i.e. pH8, pH10, pH12) were prepared using sodium carbonate solution to adjust the pH. The pH was confirmed using the VWR pH meter. Methylene Blue dye (0.0012 g) obtained from Sigma-Aldrich, was added to 15 ml of the different pH solutions to obtain a molarity of 0.0002 mM following which, 1.5 g of hydrolysed (using 11M NaOH) nylon 6 particles were added to each pH solution and left in the fridge overnight at 4 C. to allow dye adsorption. For each sample, the particles were separated and the solution was analysed at 670 nm using a CM-3600A spectrophotometer. The transmittance measured is shown in Table 5, wherein the higher the transmittance the more dye had bound to the particles and so been removed from solution. Thus, clearly the NaOH hydrolysed nylon 6 particles are selectively binding the positively charged Methylene Blue at high pH.

TABLE-US-00005 TABLE 5 Transmittance against different pHs for Methylene Blue: pH range Transmittance/A.U @670 nm pH 2 3.5 pH 4 3.7 pH 5 3.7 pH 6 3.7 pH 8 4

[0179] Clearly the results in Tables 4 and 5 show that the hydrolysed nylon 6 particles are able to selectively bind cationic and anionic molecules at different pH values.

Example 6

Amylase Adsorption and Desorption

[0180] Hydrolysed nylon 6 particles (500 g) were buffered at pH 4.5 with citric acid for 60 minutes. The particles were then rinsed with pH4.5 buffer citric acid to ensure the pH was constant. Amylase (Stainzyme Plus 12L) from Novozymes, (12 mL of a 1/100 dilution) was added to 15 g of the hydrolysed nylon 6 particles and separately to 15 g of unhydrolysed nylon 6 particles. As a control, a solution of amylase without any particles was also provided. To ensure the enzyme was adsorbed onto the surface of the nylon polymer particles the samples above were all put on a roller and left there for 1 hour to provide good interaction between the enzyme in solution and the polymer particle surface. The particles and enzyme samples were then placed in the fridge at 4 C. for a further hour.

Protein Assay to Confirm Enzyme Adsorption onto Particles

[0181] Enzyme adsorption onto the nylon 6 polymer particles was determined by measuring the depletion of protein from solution onto the particle surface, using the BioRad DC assay version of the Bradford assay, ref: Bradford, M., Anal. Biochem., 72, 248 (1976), for protein concentration estimation. Each of the three test solutions (i.e. hydrolysed particles, unhydrolysed particles and the enzyme (without particles)) had 0.3 mL of particle free liquid removed. 1.5 mL of BioRad Reagent A and 12 mL of BioRad reagent B were then added. The three solutions were gently stirred and left to stand for 15 minutes and the blue colour which developed was monitored by its transmittance at 740 nm with a Konica Minolta CM-3600A spectrophotometer. The protein concentrations were estimated based on a standard curve of known protein (bovine serum albumin) concentration.

Adsorption of Amylase

[0182] In the experiment, the enzyme solution, minus particles, is the control and there is no loss of protein. For the solution containing the hydrolysed nylon 6 particles, 94.4% of the protein was depleted from solution at pH 4.5 while in the solution containing the unhydrolysed particles 19% of the protein was depleted from solution at pH 4.5 (see Table 6 below). The difference between the two particles is attributed to the increased positive charge present on the surface of the hydrolysed nylon particles, which drives the enzyme adsorption through an electrostatic interaction.

TABLE-US-00006 TABLE 6 % Transmittance, protein concentration (mg/mL) and % adsorption values for Amlyase enzyme only, hydrolysed particles and unhydrolysed particles % Transmittance Protein conc @ 740 nm (mg/mL) % adsorption Amylase enzyme 82.88 0.140 Hydrolysed particles 89.94 0.008 94.4 Unhydrolysed Particles 83.82 0.113 19.0

Desorption of Amylase

[0183] The hydrolysed nylon 6 particles from above were removed from their amylase solutions, dried and then stirred in a beaker filled with 100 mL of soft water at pH 10. Standard Industry/Commercial Laundry Monitor WFK 10R starch stained swatches were added to each of the solutions and stirred at 50 C. for 40 minutes. The same test was applied to a beaker containing an identical concentration of enzyme to that initially added to the polymer particle solutions as a control. The swatches were then left to dry at room temperature before spectrophotometric (Konica Minolta detailed previously) measurements were obtained. The L* data for each sample (hydrolysed particles and enzyme only) were then calculated and the details of the results were as tabulated below in Table 7.

TABLE-US-00007 TABLE 7 Washed stained swatch results for amylase enzyme only and hydrolysed particles. L* Amylase enzyme 77.9 Hydrolysed particles 78.4 The higher the L* value the more starch stain is removed from the cotton.

[0184] The data show that the particles released amylase from the polymer particle surface and this was effective and in turn helped in removing the starch stain from the cotton giving an improved performance over the amylase solution.

[0185] Clearly from the above experiment it is apparent that amylase may be bound to the nylon 6 particles at low pH and the released in an active form when the pH is raised.

Example 7

Absorption/Desorption of Surfactant

1) Adsorption

[0186] 15 grams of pure Nylon 6 beads, unhydrolyzed, were buffered to pH=3 using dilute citric acid solution and then rinsed with soft water, dried and placed into a 12 mL solution of pH=10, 1 g/L sodium dodecyl benzene sulphonate (SDBS; Sigma Aldrich, UK), in 0.5M sodium carbonate (Sigma Aldrich, UK) at 21 C. for 1 hour with gentle agitation the solution was buffered to low pH=4, then left at 4 C. in the fridge for 16 hours overnight. The beads were then extracted from the sample solutions, rinsed with softened water (pCa<5 ppm) and dried. The same procedure was repeated for 15 g of hydrolysed Nylon beads (hydrolysed as described above).

2) Desorption

[0187] The dried Nylon polymer particles were placed in pH10 solution (Na.sub.2CO.sub.3, softened water) with 5 cm5 cm stain swatches (EMPA) containing particulate soil. Desorption occurred by increasing pH to 10 and by increasing the temperature to 40 C. and the dilution in water to 100 ml. In these conditions, SDBS is released into solution and is adsorbed onto the cotton substrate.

3) Application to Particulate Soil Removal

[0188] Carbon black soot-stained swatches (supplied by WFK stain set with the soot stain 9ORM stain sets supplied by WFK Bruggen, Germany) were washed in 100 mL pH 10 solution water using 15 g of SDBS-treated hydrolysed beads or SDBS-treated unhydrolysed beads at 40 C. for 10 minutes in 500 mL glass beakers, and the amount of particulate soil removed was assessed using the Konica Minolta spectrophotometer. A control sample at pH7 (softened water), using neither beads nor SDBS was also tested. The hydrolysed beads demonstrate superior wash performance compared with the unhydrolysed beads (due to more SDBS being adsorbed onto the hydrolysed beads) and this stain removal continues for at least 5 washes, as illustrated in Table 8.

TABLE-US-00008 TABLE 8 L*(vs the unwashed black soot-stained swatch) Wash 1 Wash 5 Control 0.0 0.0 Unhydrolysed Nylon 6 beads 1.0 0.5 Hydrolysed Nylon 6 beads 5.4 5.5

Example 8

Absorption/Desorption of Optical Brightening Agent

1) Adsorption

[0189] 15 g of pure Nylon 6 beads (unhydrolysed) were buffered to pH=3 using dilute citric acid solution (0.5M), rinsed with soft water, dried and placed into a 12.5 mL solution of pH=10, 10 g/L Leucophor BMB 2000 optical brightening agent (Clariant, Germany), in 0.5M sodium carbonate (Sigma Aldrich, UK) at 21 C. for 1 hour with gentle agitation and solution buffered to pH=4, then placed in the fridge at 4 C. for 16 hours overnight. The beads were then extracted from the sample solutions, rinsed with softened water (pCa<5 ppm) and dried. The same procedure was repeated for 15 g of hydrolysed Nylon 6 beads.

[0190] Uptake of OBA (optical brightening agent) to hydrolysed and unhydrolysed beads was analysed by UV-VIS analysis (Konica Minolta spectrophotometer) for the colour change of the beads after the adsorption of OBA. The date in Table 9 show that the uptake of OBA is superior for the hydrolysed beads.

TABLE-US-00009 TABLE 9 L* Unhydrolysed Nylon 6 beads 4.8 Hydrolysed Nylon 6 beads 6.0

2) Desorption

[0191] The dried Nylon 6 polymer particles were placed in pH=10 solution (0.5M Na.sub.2CO.sub.3, softened water) with 5 cm5 cm cotton swatches. Desorption occurred by increasing pH to 10 and by increasing the temperature to 40 C. and the dilution in water to 100 ml. In these conditions the OBA is released into solution and is adsorbed onto the cotton substrate (as measured by Konica Minolta spectrophotometer)

3) Application of OBA to Cotton Substrate

[0192] The amount of OBA absorbed onto the cotton swatches (cotton supplied by Phoenix Calico Ltd, Stalybridge, Manchester, Cheshire) after being released from the bead surface was evaluated as the difference, L*, between the untreated cotton substrate and the treated cotton substrate. The results presented in Table 10 show that the hydrolysed beads release more OBA beads, and demonstrate superior performance, compared with the unhydrolyzed beads. This effect continues for at least 8 washes.

TABLE-US-00010 TABLE 10 L* (vs the untreated cotton substrate) Wash 1 Wash 8 Treated unhydrolysed beads 0.8 1.2 Treated hydrolysed beads 2.3 1.7

Example 9

Absorption/Desorption of Fragrance

1) Adsorption

[0193] 15 grams of pure Nylon 6 beads were buffered to pH=3 using dilute citric acid solution and then rinsed with soft water, dried and placed into a 12 mL solution of pH=10, 10 g/L o-Vanillin (Sigma Aldrich, UK), in 0.25 g/L sodium carbonate (Sigma Aldrich, UK) at 21 C. for 1 hour with gentle agitation buffered to pH=4, then at 4 C. in the fridge for 16 hours. The beads were then extracted from the sample solutions, rinsed with softened water (pCa<5 ppm) and dried. The same procedure was repeated for 15 g of hydrolysed Nylon beads.

##STR00003##

[0194] Uptake of o-Vanillin (max=450 nm) to the beads was analysed by UV-Vis analysis (Konica Minolta spectrophotometer) of the colour change of the beads on adsorption of coloured fragrance. The results in table 11 show that the hydrolysed beads adsorb more fragrance than unhydrolysed beads.

TABLE-US-00011 TABLE 11 L* Treated unhydrolysed beads 12.8 Treated hydrolysed beads 16.1

[0195] The fragrance uptake by the polymer beads was also assessed by an experienced panel of fragrance assessors, and the results from that assessment (see Table 12) also demonstrated that an enhanced uptake of fragrance was observed for the hydrolysed beads.

TABLE-US-00012 TABLE 12 Panel for fragrance assessment of o-Vanillin on the polymer beads No smell very weak weak strong very strong Scale 1-5 1 2 3 4 5 Unhydrolysed beads 3 6 4 0 0 Hydrolysed beads 2 0 2 6 3

2) Desorption

[0196] Desorption occurred by increasing pH to 10, increasing the temperature to 40 C. and dilution in soft water to 100 ml. In these conditions, o-Vanillin is released into solution and can subsequently be adsorbed onto the cotton substrate.

3) Application of Desorbed Fragrance to Cotton

[0197] The dried Nylon particles were placed in pH=10 solution (0.5M Na.sub.2CO.sub.3, softened water) with 5 cm5 cm cotton swatches. The swatches were stirred in a 500 ml beaker with the vanillin beads and the fragrance was desorbed from the bead surface and onto the cotton swatches. An odour perception test was then carried out by a panel of 13 experienced textile fragrance assessors (see table 13) to assess the cotton swatches treated with o-Vanillin which had been desorbed from the hydrolysed Nylon beads and the unhydrolysed Nylon beads. The hydrolysed beads showed the greatest transfer of fragrance to the cotton and were superior in performance to both the unhydrolyzed beads and some free fragrance (control below) added in solution.

TABLE-US-00013 TABLE 13 Panel for cotton swatches with Vanillin No smell very weak weak strong very strong Scale 1-5 1 2 3 4 5 Unhydrolysed beads 10 3 0 0 0 Hydrolysed beads 1 0 4 8 0 Control fragrance only 2 6 5 0 0

Example 10

Absorption/Desorption of Salicylic Acid

1) Adsorption

[0198] 15 grams of pure hydrolysed Nylon 6 beads were buffered to pH=3 using 0.5M citric acid solution and then rinsed with soft water, dried and placed into a 12 mL solution at pH=10. 0.5% salicylic acid solution (Sigma Aldrich, UK), in 0.5M sodium carbonate (Sigma Aldrich, UK) was then added to the hydrolysed beads and the adsorption process carried out at pH=4, at 21 C. for 1 hour with gentle agitation, then these beads were placed in the fridge at 4 C. for 16 hours. The beads were then extracted from the sample solutions, rinsed with softened water (pCa<5 ppm) and dried. The same procedure was repeated for 15 g of unhydrolysed pure Nylon beads.

[0199] 0.5 mL of the soak solutions of hydrolysed beads, non-hydrolysed beads were added to 10 mL of 1% ferric (III) chloride (Merck, Germany). A control sample which contained no beads was also prepared. The resulting change of colour for each sample was then compared to a calibration of known dilutions of salicylic acid and ferric (III) chloride to determine the concentration of the salicylic acid in the solutions for each sample calculated from the uptake of salicylic acid by each type of bead. The intensity of the colour indicates the concentration of salicylic acid. The control sample showed dark violet-blue colour indicating the presence of high concentration of the salicylic acid. The hydrolysed beads solution showed a light violet/brown colour because the salicylic acid had been adsorbed onto the positively charged polymer bead surface. The unhydrolysed beads sample displayed a fairly dark violet-blue colour approaching that of the control sample, indicating the presence of relatively high concentration of salicylic acid, but the colour differential indicated that a small amount of salicylic acid had been adsorbed onto the polymer bead surface.

2) Desorption

[0200] The dried polymer beads with the adsorbed salicylic acid were placed in a 500 ml beaker and 100 ml soft water added. The pH was increased from 4 to 10 using 0.5M sodium carbonate solution. In addition, the temperature was increased to 40 C. to drive the desorption of salicylic acid from the bead surface.

3) Application to Cotton

[0201] The beads were placed and stirred in a 500 mL beaker containing 100 mL soft water and a cotton swatch (1.5 g; 5 cm5 cm). A control with salicylic acid but no beads was evaluated at the same time. The swatches were then dried and stirred with ferric (II) chloride solution for 5 minutes before rinsing with soft water and drying. The swatches were then analysed using the UV-VIS Spectrophotometer (Konica Minolta). The data in Table 14 demonstrate that the salicylic acid was transferred from the bead surface to the cotton with a slightly higher level of transfer for the hydrolysed beads.

TABLE-US-00014 TABLE 14 Sample L* Salicylic Acid 13.1 Unhydrolysed beads treated with salicylic 16.2 acid Hydrolysed beads treated with salicylic acid 16.7

Example 11

Hygiene

1) Adsorption

[0202] Hydrolysed and unhydrolysed nylon beads were treated with Caflon BIT 20 (1 gram in 100 mL pH 10 solution (Univar, UK). Incubated over night at 4 C. Beads were then rinsed with soft water and dried. Then 500 uL of sump water (pH 10) was inoculated on the surface of the petri dish (nutrient+Blue+TTC; VWR Chemicals, Belgium). Pure nylon, hydrolysed and non-hydrolysed beads treated with Caflon BIT 20 were placed on the petri dish, and incubated at room temperature for 48 hrs before microscopic analysis was undertaken.

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2) Application of Caflon BIT 20

[0203] Hydrolysed beads treated with Caflon BIT 20 displayed an inhibition zone and no bacterial growth. The unhydrolysed beads treated with Caflon BIT 20 showed some bacterial growth, but not as much growth as the untreated beads. [0204] The average inhibition zone diameter for hydrolysed beads treated with Caflon BIT 20 is 2 cm2 cm. On a scale of 1-4 (where, 1no change, 2 small zone, 3medium zone, 4large zone), the average inhibition zone diameter was 4. [0205] The average inhibition zone diameter for unhydrolysed beads treated with Caflon BIT 20 is 0.3 cm0.3 cm. On the above-noted scale of 1-4, the average inhibition zone diameter was 2.

[0206] The results indicate that the hydrolysed beads with Caflon BIT 20 had excellent antimicrobial activity.

Example 12

Bleaching

1) Adsorption

[0207] 15 grams of pure Nylon 6 beads were buffered to pH3 using dilute citric acid solution and then rinsed with soft water, dried and placed into a 12 mL solution of pH10, 10 g/L sodium perborate tetrahydrate (Sigma Aldrich, UK), in 0.25 g/L sodium carbonate (Sigma Aldrich, UK) at 21 C. for 1 hour with gentle agitation, then at 4 C. in the fridge for 16 hours. The beads were then extracted from the sample solutions, rinsed with softened water (pCa<5 ppm) and dried. The same procedure was repeated for 15 g of hydrolysed Nylon 6 beads.

2) Desorption

[0208] The dried Nylon polymer particles were placed in a 100 mL pH=10 solution with 5 cm5 cm tea-stain swatches. Desorption occurred by (i) increasing pH from 4 to 10 (0.5M sodium carbonate), (ii) increasing the temperature to 40 C., and (iii) dilution in water to 100 mL. In these conditions, the hydroperoxide anion is released into solution and this is then subsequently adsorbed onto the curry stained cotton swatches.

3) Application to Curry Stain Removal

[0209] The curry stain was prepared using the following procedure. Cotton swatches (circular, with a diameter of 5 cm) were cut out using a template board. A small sponge was then used to apply the curry sauce (Morrison's own label curry sauce, Morrisons, UK) to ensure full coverage of the cotton swatches. The swatches were then left to dry at room temperature for 4 days before use. The curry-stained swatches were washed in 100 ml soft water at pH=10 using 15 g of sodium perborate-treated beads (both the hydrolysed and unhydrolysed beads) at 40 C. for 10 minutes in 500 mL glass beakers, and the amount of curry stain removed was assessed using the Konica Minolta spectrophotometer. A second control was conducted in the same wash conditions, using 1 mL pH=10 with 10 g/L sodium perborate tetrahydrate and no beads. A third control was similarly conducted at pH=10 (softened water), using neither beads nor sodium perborate tetrahydrate. The results are shown in Table 15.

TABLE-US-00015 TABLE 15 L* Soft water only 4.1 Sodium perborate tetrahydrate, no beads 4.6 Unhydrolysed Nylon 6 beads 4.8 Hydrolysed Nylon 6 beads 7.0

Example 13

Layered Beads

[0210] This Example is a comparative example and corresponds to Example 4 of WO-20141006424-A. The data in the table below demonstrate the performance difference of the present invention over the layered beads of this prior art.

1) Bead Preparation

[0211] 15 g of pure Nylon beads were soaked sequentially in 1 mg/mL PEI (polyethyleneimine), then 1 mg/mL Stainzyme Plus 12L (an amylase commercially available from Novozyme), then 1 mg/mL PEI, then 1 mg/mL Stainzyme Plus 12L. Each soak lasted for 2 hours, at 21 C. with gentle agitation. In each case, 11.25 ml of solution was used, sufficient to cover the beads in the vial. Softened water was used for dilution of PEI and Stainzyme. The beads were rinsed in soft water and dried with a paper towel between sequential washes. Fresh PEI and Stainzyme solutions were used for the first and third, and second and fourth soaks respectively. The beads were rinsed in soft water and dried with a paper towel prior to washes. The beads were then finally rinsed in soft water and dried.

2) Enzyme Adsorption and Application for Soil Removal

[0212] 5 cm5 cm starch-stained swatches (10R, WFK) were washed in 100 ml soft water using 15 g of layered beads at 21 C. for 10 minutes in 500 mL glass beakers, and the amount of starch stain removed was assessed using the Konica Minolta spectrophotometer. A control test with soft water only, and a control test with just the Stainzyme enzyme only no beads, were also undertaken. In order to determine the quantity of Stainzyme solution to be used in the enzyme-only control, the beads were weighed between consecutive soaks during their preparation, and the mass of 1 mg/mL Stainzyme solution adsorbed calculated as 0.26 g. The method of adsorption and desorption of Stainzyme enzyme for hydrolysed and unhydrolysed beads is included in Example 6 herein. The results are shown in Table 16.

TABLE-US-00016 TABLE 16 L* Starch stain swatch Wash 1 Wash 2 Wash 3 Soft water only 0.0 0.0 0.0 No beads, Stainzyme enzyme only 0.4 0.6 0.7 Layered nylon 6 beads 2.9 1.7 0.7 Unhydrolysed beads with Stainzyme 7.9 8.4 11 Hydrolysed beads with Stainzyme 11.8 12.4 12.3

[0213] The results demonstrate that the hydrolysed beads and the unhydrolysed beads within the scope of the invention are superior in removing starch comparing to the layered nylon beads of the prior art.

Example 14

Cellulase Adsorption

[0214] 12 mL of a solution of 1 g of cellulase ((Cellosoft 19500; Novozymes) in 100 mL of pH 4/4.5 soft water solution (citric acid, Fluka Analytical, UK) was adsorbed onto 15 grams of beads (both hydrolysed and unhydrolysed bead samples were prepared). The Bio-Rad Assay was performed to determine the quantity of enzyme adsorbed onto the hydrolysed and unhydrolysed beads. The data in table 17 indicate that cellulase is adsorbed onto both types of bead but preferentially onto the hydrolysed bead surface (70.3% of the enzyme is adsorbed from solution).

TABLE-US-00017 TABLE 17 % adsorption of cellulase onto the bead surface Hydrolysed nylon 6 beads 70.3 Unhydrolysed nylon 6 beads 33.3