GB2614284A

GB2614284A - Anitmicrobial compositions and eyewear

Info

Publication number: GB2614284A
Application number: GB2118902.2A
Authority: GB
Inventors: Matthew Thorn Daniel; Gary Conway James
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-12-23
Filing date: 2021-12-23
Publication date: 2023-07-05
Also published as: GB202118902D0

Abstract

A polymer composition comprises nanoparticles dispersed in cellulose acetate propionate, polycarbonate, or acrylonitrile-butadiene-styrene, wherein the nanoparticles comprise silver orthophosphate. Preferably, the nanoparticles also contain silver oxide and/or silver sulphadiazine and have a particle size of 1-1000 nm, especially 1-100 nm. The composition may comprise a further polymer, such as a polyethylene-vinyl acetate elastomer. An article, such as a spectacles case, spectacles, sunglasses, safety glasses, or other optical equipment, comprising the composition is also disclosed. The article will typically have antimicrobial properties. In another aspect, a method of manufacturing an article comprises the steps of (i) dispersing silver orthophosphate nanoparticles into a carrier to form a dispersion, (ii) blending the dispersion into cellulose acetate propionate, polycarbonate, or acrylonitrile-butadiene-styrene polymer to form a blend, and (iii) shaping the blend to produce the article. The shaping step may comprise injection moulding.

Description

Antimicrobial compositions and eyewear

Field of the Invention

The present invention relates to a composition comprising silver-containing nanoparticles dispersed in a polymer, articles, for example articles of eyewear and spectacle cases, comprising such a composition, and a method of preparing such articles. In particular, the invention relates to silver orthophosphate-containing nanoparticles dispersed in a polymer comprising cellulose acetate propionate, a polyc,arbonate, acrylonitrile butadiene styrene, or a mixture thereof

Background of the Invention

Eyewear is worn for a variety of purposes. Spectacles typically include corrective lenses which refract light entering the human eye, in order to correct faulty vision. Sunglasses contain lenses which filter visible and/or ultraviolet light to avoid short-or long-term impairment of vision due to exposure of the eye to bright sunlight. Spectacles and sunglasses may also be worn for aesthetic purposes. The lenses of spectacles and sunglasses are held in place by a frame, which may be fully or partially formed from a polymeric material. Safety glasses protect the eyes of a user from contact with foreign objects such as flying chemicals or debris. The lenses of safety glasses are usually formed from a tough, transparent polymeric material. The frames of safety glasses are often formed from the same material as the lens. When not being worn, eyewear may be stored in a spectacle case, which is typically formed from a polymeric material.

Traditionally eyewear has been manufactured from either cellulose acetate ((C51-11005)n,) cutting out the shape of the spectacle frames from a block of material or a variety of metals and alloys through a combination of culling and welding/soldering. The development of new thermoplastic materials has enabled production of spectacle frames, sunglasses, safety glasses and spectacle cases to be manufactured using injection moulding technology. The ability to injection mould with various thermoplastics opens up new opportunities for additives to be applied to the plastic masterbatch and in turn be present in the spectacle frames, sunglasses, safety glasses and spectacle cases.

Transmission of microbes may occur through the handling of eyewear. An article of eyewear is typically worn by resting the frame of the eyewear on the nose bridge and ears of the user.

When putting on, taking off, or adjusting eyewear, microbes may transfer from the hands of the user to the frame and subsequently to the face of the user, and vice versa. A point of importance is the fact that the face is an area which is vulnerable to infection. Transfer of microbes between a user's hands and a spectacle case may occur when the user is putting away or retrieving an article of eyewear from the spectacle case. Microbes may be transmitted from one individual to another where eyewear is shared between multiple users, such as safety glasses being shared in a laboratory or industrial setting. Furthermore, some users of eyewear, such as children, may occasionally place parts of the frame, such as an earpiece, into their mouths, allowing microbes to transfer from the frame to the inside of the user's body.

Detailed Description of the Invention

It is one aim of the present invention, among others, to provide eyewear that addresses at least one disadvantage of the prior art, whether identified here or elsewhere, or to provide an alternative to existing eyewear. For instance, it may be an aim of the present invention to provide an article of eyewear which possesses antimicrobial properties.

According to aspects of the present invention, there is provided a composition, an article (for example an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment), and a method as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

According to a first aspect of the present invention, there is provided a composition comprising nanoparticles dispersed in a polymer, wherein the nanoparticles comprise silver orthophosphate, and wherein the polymer comprises cellulose acetate propionate, a polycarbonate, acrylonitrile butadiene styrene, or a mixture thereof The inventors have found that it is possible to prepare thermoplastic polymeric compositions of cellulose acetate propionate, a polycarbonate and/or acrylonitrile butadiene styrene (ABS) incorporating dispersed nanoparticles wherein the nanoparticles comprise silver orthophosphate. The nanoparticles include silver ions, which may be released therefrom to provide an antimicrobial effect. The compositions possess advantageous antimicrobial properties due to the presence of silver ions dispersed in the composition. These properties are believed to be effectively permanent, as the silver ions are present throughout the composition rather than just as part of a coating at the surface of the composition. The composition may advantageously be applied as a thin film or injection moulded.

The nanoparticles suitably have a size of from 1 to 1000 nm, such as from 1 to 100 nm.

Preferably the nanoparticles have a size of less than 100 nm.

The nanoparticles suitably have a positive zeta potential of at least 20 mV, such as at least 25 mV, preferably at least 30 mV.

Suitably, the composition comprises a colloidal suspension of the nanoparticles. By "colloidal suspension" we mean that the nanoparticles are homogeneously dispersed in a carrier in which the nanoparticles are insoluble. The carrier may be a polymer, such as cellulose acetate propionate, a polycarbonate, acrylonitrile butadiene styrene, poly(ethylene-vinyl acetate), or a mixture thereof The nanoparticles may comprise silver oxide, silver sulfadiazine, or a mixture thereof The nanoparticles preferably comprise silver oxide. The nanoparticles may comprise silver oxide and silver sulfadiazine.

In embodiments where the nanoparticles comprise both silver oxide and silver sulfadiazine, the weight ratio of silver oxide to silver sulfadiazine may be from 1:1 to 20:1, suitably from 5:1 to 15:1, for example 9:1.

The composition may comprise silver oxide, silver sulfadiazine, or a mixture thereof in an amount of from 100 to 5000 ppm, suitably from 1500 to 4000 ppm, for example from 2500 to 3500 ppm based on the total weight of the composition. The composition may comprise silver oxide in an amount of from 1000 to 5000 ppm, suitably from 1500 to 3500 ppm, for example from 2500 to 3000 ppm based on the total weight of the composition. The composition may comprise silver sulfadiazine in an amount of from 100 to 1000 ppm, suitably from 100 to 500 ppm, for example from 200 to 400 ppm based on the total weight of the composition.

The composition may comprise further components. Suitably the composition comprises gold nanoparticles, silver nanoparticles, zinc oxide nanoparticles, chlorite, or a mixture thereof Preferably the composition comprises gold nanoparticles, silver nanoparticles, zinc oxide nanoparticles, and chlorite.

The composition may comprise gold nanoparticles in an amount of from 0.1 to 10 ppm, such as from 0.5 to 2 ppm based on the total weight of the composition. The composition may comprise silver nanoparticles in an amount of from 1 to 20 ppm, such as from 3 to 10 ppm based on the total weight of the composition. The composition may comprise zinc oxide nanoparticles in an amount of from 30 to 150 ppm, such as from 50 to 100 ppm based on the total weight of the composition. The composition may comprise chlorite in an amount of from 10 to 100 ppm, such as from 20 to 50 ppm based on the total weight of the composition The polymer comprises cellulose acetate propionate, a polycarbonate, acrylonitrile butadiene styrene, or a mixture thereof.

The cellulose acetate propionate may have any suitable number average molecular weight (Mn), such as a number average molecular weight of from 1000 to 3000 g/mol, suitably from 1500 to 2500 g/mol, from example from 1700 to 1900 g/mol. The cellulose acetate propionate suitably has a melting point of from about 188 to 210 °C. The cellulose acetate propionate suitably has a flash point of about 299.90 °C.

The polycarbonate may have any suitable number average molecular weight, such as a number average molecular weight of from 150 to 400 g/mol, suitably from 200 to 300 g/mol, for example from 225 to 275 g/mol. The polycarbonate suitably has a melting point of from about 280 to 320 °C. The polycarbonate suitably has a flash point of about 450 °C.

The acrylonitrile butadiene styrene (ABS) may have any suitable number average molecular weight, such as a number average molecular weight of from 100 to 350 g/mol, suitably from 150 to 300 g/mol, for example from 180 to 240 g/mol. The ABS suitably has a melting point of about 105 °C. The ABS suitably has a flash point of about 207 °C.

Suitable methods for measuring the number average molecular weight of the polymer will be well known to the person skilled in the art. As a non-limiting example, the number average molecular weight may be determined by gel permeation chromatography using a polystyrene standard. Suitably, the number average molecular weight may be determined by gel permeation chromatography using a polystyrene standard according to ASTM D6579-11 ("Standard Practice for Molecular Weight Averages and Molecular Weight Distribution of Hydrocarbon, Rosin and Terpene Resins by Size Exclusion Chromatography". Detector: Differential Refractometer, solvent: 5% acetic acid in dimethyl formamide, retention time marker: system peak, sample concentration: 8mg/ml, column temperature: 80°C, injection volume: 100pL, flow rate: lcm3/min).

The composition of the first aspect may comprise at least one further polymer, i.e. a further polymer other than cellulose acetate propionate, a polycarbonate, or acrylonitrile butadiene styrene. Suitably the at least one further polymer comprises an elastomeric polymer, such as poly(ethylene-vinyl acetate) (PEVA).

The poly(ethylene-vinyl acetate) may have any suitable melting point. The poly(ethylene-vinyl acetate) may have a melting point of from 80 to 110 °C, suitably from 85 to 105°C, for example from 90 to 100 °C. In some embodiments the poly(ethylene-vinyl acetate) has a melting point of 94 °C. An example of a suitable poly(ethylene-vinyl acetate) is Escoreneml Ultra LD 705.MJ, which is commercially available.

According to a second aspect of the present invention, there is provided an article, for example an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment, comprising a composition according to the first aspect.

For example, there may be provided an article of eyewear comprising a composition according to the first aspect.

For example, there may be provided a spectacle case comprising a composition according to the first aspect.

For example, there may be provided a face-supporting component for optical refraction equipment or associated optical equipment, wherein the face-supporting component comprises a composition according to the first aspect. By face-supporting component, we mean a component, such as a chin rest or a forehead rest, with which a face will come into contact when using optical refraction equipment or associated optical equipment. By optical refraction equipment or associated optical equipment, we mean equipment which may be used to carry out optical refraction tests or other types of eye tests.

The suitable features and advantages of the article(s) are as defined in relation to the first aspect. The article of eyewear suitably comprises a frame. The frame suitably comprises earpieces.

The frame or a portion of the frame suitably comprises the composition according to the first aspect. Suitably at least a portion of the earpieces comprise the composition according to the first aspect. In some embodiments the earpieces are entirely formed from a composition according to the first aspect.

The article of eyewear suitably comprises a composition according to the first aspect, wherein the polymer comprises cellulose acetate propionate or a polycarbonate.

The article of eyewear may be selected from spectacles, sunglasses, or safety glasses. The spectacles suitably comprise a composition according to the first aspect wherein the polymer comprises cellulose acetate propionate. The sunglasses suitably comprise a composition according to the first aspect wherein the polymer comprises cellulose acetate propionate. In particular, the spectacles or the sunglasses suitably comprise a frame comprising a composition according to the first aspect wherein the polymer comprises cellulose acetate propionate. The safety glasses suitably comprise a composition according to the first aspect wherein the polymer comprises a polycarbonate. The safety glasses suitably comprise lenses and/or a frame comprising a composition according to the first aspect wherein the polymer comprises a polycarbonate.

The spectacle case according to the second aspect suitably comprises a composition according to the first aspect wherein the polymer comprises acrylonitrile butadiene styrene.

According to a third aspect of the present invention, there is provided a method of manufacturing an article, for example an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment, the method comprising the steps of: (a) dispersing nanoparticles into a carrier to form a dispersion, wherein the nanoparticles comprise silver orthophosphate; (b) blending the dispersion into a polymer to form a blend, wherein the polymer comprises cellulose acetate propionate, a polycarbonate, acrylonitrile butadiene styrene, or a mixture thereof; and (c) shaping the blend to form a shaped article.

When the article is an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment, the method may further comprise a step (d) of incorporating the shaped article into an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment. The shaped article may be a frame or a portion of a frame for an article of eyewear, for example wherein the article of eyewear is selected from spectacles, sunglasses or safety glasses.

Suitably the steps of the method according to the third aspect are carried out in the order step (a) followed by step (b) followed by step (c) followed by step (d) The suitable features and advantages of the method of the third aspect, for example in relation to the article (for example article of eyewear, spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment), the nanoparticles, and the polymer are as defined in relation to the first and second aspects.

Step (a) of the method according to the third aspect comprises dispersing nanoparticles into a carrier to form a dispersion. The dispersing may be carried out by using a high speed mixer.

Suitably any particles in the dispersion have a size of from 1 to 1000 nm, such as from 1 to 100 nm. Preferably the particles have a size of less than 100 nm.

The nanoparticles in the dispersion suitably have a positive zeta potential of at least 20 mV, such as at least 25 mV, preferably at least 30 mV.

The nanoparticles may be prepared by any suitable technique. One suitable technique may comprise heating silver (which may be in the form of a silver compound, such as silver oxide) in the presence of phosphoric acid.

The dispersion may comprise the nanoparticles in an amount of from 10 to 90 wt%, suitably from to 75 wt%, for example from 40 to 60 wt% based on the total weight of the dispersion.

The carrier suitably comprises at least one polymer which is not selected from cellulose acetate propionate, a polycarbonate, acrylonitrile butadiene styrene, or a mixture thereof. Suitably the at least one polymer comprises poly(ethylene-vinyl acetate) (PEVA).

The poly(ethylene-vinyl acetate) may have any suitable melting point. The poly(ethylene-vinyl acetate) may have a melting point of from 80 to 110 °C, suitably from 85 to 10500, for example from 90 to 100 °C. In some embodiments the poly(ethylene-vinyl acetate) has a melting point of 94 °C. An example of a suitable poly(ethylene-vinyl acetate) is EscoreneTM Ultra LD 705.MJ,which is commercially available.

The carrier is suitably in the form of a powder. Suitably the powder has a particle size of from 1 to 1000 nm, such as from 1 to 100 nm. Preferably the powder has a particle size of less than 100 nm.

Step (b) of the method according to the third aspect comprises blending the dispersion into a polymer to form a blend. The blending is suitably carried out using a twin screw extruder, a continuous mixer, or a Banbury mixer.

Step (b) may comprise blending the dispersion into the polymer in a weight ratio of from 1:100 to 1:300, suitably from 1:150 to 1:200, for example from 1:160 to 1:170.

The blend may comprise silver oxide, silver sulfadiazine, or a mixture thereof in an amount of from 100 to 5000 ppm, suitably from 1500 to 4000 ppm, for example from 2500 to 3500 ppm based on the total weight of the blend. The blend may comprise silver oxide in an amount of from 1000 to 5000 ppm, suitably from 1500 to 3500 ppm, for example from 2500 to 3000 ppm based on the total weight of the blend. The blend may comprise silver sulfadiazine in an amount of from 100 to 1000 ppm, suitably from 100 to 500 ppm, for example from 200 to 400 ppm based on the total weight of the blend.

B

The blend may comprise gold nanoparticles in an amount of from 0.1 to 10 ppm, such as from 0.5 to 2 ppm based on the total weight of the blend. The blend may comprise silver nanoparticles in an amount of from 1 to 20 ppm, such as from 3 to 10 ppm based on the total weight of the blend. The blend may comprise zinc oxide nanoparticles in an amount of from 30 to 150 ppm, such as from 50 to 100 ppm based on the total weight of the blend. The blend may comprise chlorite in an amount of from 10 to 100 ppm, such as from 20 to 50 ppm based on the total weight of the blend.

Step (c) of the method according to the third aspect comprises shaping the blend to form a shaped article. Suitably the shaping comprises injection moulding. Suitable methods of injection moulding will be known to the skilled person. In some embodiments step (c) comprises coating the blend, for example as a thin film, onto an article precursor. Said article precursor may be formed from any suitable material, such as metals or polymers.

The shaped article may be a frame or a portion of a frame for an article of eyewear. The portion of a frame suitably comprises an earpiece.

For a better understanding of the invention, reference will now be made to the following non-limiting example.

Example

Preparation and testing of nanoparticles Silver oxide and silver were reduced by heating with phosphoric acid at 90 °C for 30 min, and then dispersed to obtain colloidal silver oxide and silver orthophosphate nanoparticles. Further components were added to obtain a colloidal suspension of silver oxide and silver orthophosphate nanoparticles, gold nanoparticles (1 ppm), silver nanoparticles (5 ppm), zinc oxide nanoparticles (60 ppm) and chlorite (42.5 ppm). The nanoparticles had a positive zeta potential of + 32.81 mV.

The antiviral activity of the nanoparticles against microorganisms and viruses was examined by a plaque reduction assay. The nanoparticles inhibited a high percentage of plaque formation by these microorganisms and virus strains. The ability of the nanoparticles to inhibit virus replication, to inhibit binding of microorganisms and viruses to cells, and to inhibit syncyfium formation was also confirmed by assays. Nanoparticles having a particle size of 0.1 pm were effective against microorganisms and viruses.

It is believed that nanoparticles comprising silver orthophosphate, silver oxide (when present) and/or silver sulfadiazine (when present) may interact with virus surface glycoproteins and thus interfere with viral attachment and entry into host cells. It is believed that silver oxide and silver orthophosphate nanoparticles may also exert antiviral activity by interaction with viral genomes.

Preparation of polymer compositions and articles Poly(ethylene-vinyl acetate) was pulverised cryogenically or by jet milling to prepare a powder having particle sizes of less than 0.5 pm. A volumetric doser was used with a gear ratio of 38:1 or 75:1 coupled to a dosing screw of 12, with an output ranging from 0.1 to 32 kg/hour.

The PEVA powder was added to a high speed mixer. A colloidal suspension of nanoparticles as prepared above was added to the PEVA powder stepwise with mixing. In each step the amount of nanoparticles added was 5 wt% of the amount of PEVA. After 20 additions the mixture comprised 50 wt% of the PEVA powder and 50 wt% of the nanoparticles, and the mixer was closed and spun on high speed for a further 10 minutes. The resulting dispersion had a uniform consistency and the PEVA powder and nanoparticles were evenly dispersed, with a particle size of less than 0.1 pm.

The dispersion of PEVA and nanoparticles was added to cellulose acetate propionate, polycarbonate, or acrylonitrile butadiene styrene (ABS) in a weight ratio of 1:167. The mixture was blended using a twin screw extruder, a continuous mixer or a Banbury mixer.

The resulting blend was injection moulded into spectacle frames, safety glasses, or spectacle cases.

The example embodiments described above may provide articles of eyewear, spectacle cases, or a face-supporting component for optical refraction equipment or associated optical equipment having long-term antimicrobial properties. This addresses the problem of microbial transmission caused through contact with eyewear, spectacle cases and a face-supporting component for optical refraction equipment or associated optical equipment.

Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims.

Throughout this specification, the term "comprising" or "comprises" means including the component(s) specified but not to the exclusion of the presence of other components. The term "consisting essentially or or "consists essentially or means including the components specified but excluding other components except for materials present as impurities, unavoidable materials present as a result of processes used to provide the components, and components added for a purpose other than achieving the technical effect of the invention. Typically, when referring to compositions, a composition consisting essentially of a set of components will comprise less than 5% by weight, typically less than 3% by weight, more typically less than 1% by weight of non-specified components.

The term "consisting of' or "consists of' means including the components specified but excluding addition of other components.

Whenever appropriate, depending upon the context, the use of the term "comprises" or "comprising" may also be taken to encompass or include the meaning "consists essentially of' or "consisting essentially of, and may also be taken to include the meaning "consists of or "consisting of.

For the avoidance of doubt, where amounts of components in a composition are described in wt%, this means the weight percentage of the specified component in relation to the whole composition referred to. For example, "wherein the dispersion comprises the nanoparticles in an amount of from 10 to 90 wt%" means that 10 to 90 wt% of the dispersion is provided by the nanoparticles.

The optional features set out herein may be used either individually or in combination with each other where appropriate and particularly in the combinations as set out in the accompanying claims. The optional features for each aspect or exemplary embodiment of the invention as set out herein are also to be read as applicable to any other aspect or exemplary embodiments of the invention, where appropriate. In other words, the skilled person reading this specification should consider the optional features for each exemplary embodiment of the invention as interchangeable and combinable between different exemplary embodiments.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, and drawings) may be replaced by alternative features sewing the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

Claims 1. A composition comprising nanoparticles dispersed in a polymer, wherein the nanoparticles comprise silver orthophosphate, and wherein the polymer comprises cellulose acetate propionate, a polycarbonate, acrylonitrile butadiene styrene, or a mixture thereof.
2. The composition of claim 1, wherein the nanoparticles comprise silver oxide, silver sulfadiazine, or a mixture thereof
3. The composition of claim 2, wherein the composition comprises silver oxide.
4. The composition of any preceding claim, wherein the cellulose acetate propionate has a number average molecular weight of from 1000 to 3000 g/mol.
5. The composition of any preceding claim, wherein the polycarbonate has a number average molecular weight of from 150 to 400 g/mol.
6. The composition of any preceding claim, wherein the acrylonitrile butadiene styrene has a number average molecular weight of from 100 to 350 g/mol.
7. The composition of any preceding claim, wherein the composition comprises at least one further polymer.
8. The composition of claim 7, wherein the at least one further polymer comprises an elastomeric polymer, for example poly(ethylene-vinyl acetate).
9. An article, for example an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment, comprising a composition according to any preceding claim.
10. An article of eyewear comprising a frame, wherein the frame or a portion of the frame comprises the composition according to any one of claims 1 to 8.
11. The article of eyewear of claim 10, wherein the polymer comprises cellulose acetate propionate or a polycarbonate.
12. The article of eyewear of claim 10 or claim 11, wherein the article of eyewear is selected from spectacles, sunglasses, or safety glasses.
13. A spectacle case comprising a composition according to any one of claims 1 to 8, wherein the polymer comprises acrylonitrile butadiene styrene.
14. A method of manufacturing an article, for example an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment, the method comprising the steps of: (a) dispersing nanoparticles into a carrier to form a dispersion, wherein the nanoparticles comprise silver orthophosphate; (b) blending the dispersion into a polymer to form a blend, wherein the polymer comprises cellulose acetate propionate, a polycarbonate, acrylonitrile butadiene styrene, or a mixture thereof; and (c) shaping the blend to form a shaped article.
15. A method of claim 14, wherein the article is an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment, further comprising the step (d) of incorporating the shaped article into an article of eyewear, a spectacle case, or a face-supporting component for optical refraction equipment or associated optical equipment.
16. A method of claim 14 or claim 15, wherein the shaped article is a frame or a portion of a frame for an article of eyewear, for example wherein the article of eyewear is selected from spectacles, sunglasses, or safety glasses.
17. The method of any one of claims 14 to 16, wherein the nanoparticles comprise silver oxide, silver sulfadiazine, or a mixture thereof.
18. The method of any one of claims 14 to 17, wherein the blend comprises silver oxide
19. The method of any one of claims 14 to 18, wherein the cellulose acetate propionate has a number average molecular weight of from 1000 to 3000 g/mol.
20. The method of any one of claims 14 to 19, wherein the polycarbonate has a number average molecular weight of from 150 to 400 g/mol.
21. The method of any one of claims 14 to 20, wherein the acrylonitrile butadiene styrene has a number average molecular weight of from 100 to 350 g/mol.
22. The method of any one of claims 14 to 21, wherein the carrier comprises an elastomeric polymer, for example poly(ethylene-vinyl acetate).
23. The method of any one of claims 14 to 22, wherein the shaping in step (c) comprises injection moulding.