Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D498/00—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and oxygen atoms as the only ring hetero atoms
  • C07D498/02—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and oxygen atoms as the only ring hetero atoms in which the condensed system contains two hetero rings
  • C07D498/10—Spiro-condensed systems
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
  • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F220/10—Esters
  • C08F220/26—Esters containing oxygen in addition to the carboxy oxygen
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K9/00—Tenebrescent materials, i.e. materials for which the range of wavelengths for energy absorption is changed as a result of excitation by some form of energy
  • C09K9/02—Organic tenebrescent materials
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/20—Filters
  • G02B5/22—Absorbing filters
  • G02B5/23—Photochromic filters

Definitions

• the present invention relates to the manufacture of plastic optical articles such as video discs, ophthalmic lenses and the like.
• the present invention relates to photochromic monomers and the manufacture of photochromic optical articles incorporating same.
• United States Patent No. 3,212,898 describes preparing a photosensitive composition by suspending a photochromic benzospiropyran in a preformed polyester resin.
• United States Patent No. 3,666,352 describes dispersing a mercury thiocarbazone compound in a solidified plasticised vinyl chloride-vinyl acetate copolymer, which copolymer is laminated between two plastic or glass layers, thereby to form a photochromic sunglass lens.
• organic photochromic dyes must be provided in regions or zones of constant thickness, independent of the optical geometry of the lens.
• Surface imbibition is the only commercial process for achieving a satisfactory product.
• the prior art describes the inclusion of photochromic dyes into the subsurface regions of a plastic lens by first positioning a polymeric or other carrier of photochromic dye physically against the surface of the lens and then using heat (in the range 100 to 150°C) to cause the dyes to undergo sorption and diffuse into the lens.
• the depleted carrier is removed from the lens after the passage of sufficient time at elevated temperature, typically of order 1/2 to 4 hours. It is found that adequate darkening is achieved with inclusion of 5 to 10 m gm/mm 2 of surface diffused to a depth of about 50 ⁇ m.
• the average dye concentration in this region of the lens is in the range of 0.1 to 0.2 mgm/mm ⁇ , or 7 to 14% (w/w) of the polymer weight in that region.
• the carrier must accommodate a sufficient concentration of dye in sufficient volume to deliver the required level of dopant.
• carrier films are in the range 50 to 80 ⁇ m thick. The intensity and duration of the heating step should be sufficient to obtain thermal transfer by permeation of the dyes without decomposing them or causing significant softening of the host polymer (lens). Either decomposition or softening will result in lenses being rejected.
• An alternative approach is to include the dyes within an optical coating resin and applying the coating to the lens directly.
• Optical coatings thus applied are rarely thicker than 10 ⁇ m because of declining optical quality and the magnification of stresses caused by differential shrinkage of thick coatings. Because of this thickness limitation, the optical density achieved by this approach falls well short of the target levels.
• an alternative process could be devised to minimise or avoid the effect that elevated temperature has upon both the dyes and the polymer. It is accordingly an object of the present invention to overcome or at least alleviate one or more of the difficulties and deficiencies related to the prior art.
• n is an integer of 0 to 5;
• P is a photochromic dye moiety or derivative thereof;
• S is an organic spacer group;
• R is a polymerisable group.
• the photochromic monomer according to this aspect may be incorporated in a cross-linking polymeric casting composition directly, or may be incorporated in a thin layer coating composition. Applicant has surprisingly found that when the photochromic monomer according to this aspect of the invention is incorporated into a cross-linking polymeric casting composition, the photochromic material has a reduced sensitivity to temperature. The utilisation of the photochromic monomer may eliminate the necessity for a separate photochromic process on an optical article.
• the photochromic dye moiety or derivative P may be of any suitable type. An hydroxy derivative may be used. P may be derived from a photochromic dye selected from one or more of the group consisting of anthraquinones, phthalocyanines, spiro-oxazines, chromenes, pyrans including spiro-pyrans and fulgides. A spiro-oxazine residue is preferred.
• Preferred photochromic dyes may be selected from the group consisting of
• photochromic dye moiety which may be used may extend to conventional tinting dyes.
• the polymerisable group R may be any reactive group capable of forming a polymer.
• An ethyleneically unsaturated group is preferred.
• An olefinic, allylic, polythiol, vinyl, acrylic or polyisocyanate group may be used.
• An acrylic or methacrylic group is preferred.
• An acrylate or methacrylate ester may be used.
• the polymerisable group R may function to improve the solubility of the photochromic monomer in the monomer mix.
• the organic spacer group S when present, may be of any suitable type.
• the group S may be selected from the group consisting of alkyl of 1 to 25 carbon atoms, preferably 1 to 6 carbon atoms; alkoxy of 1 to 25 carbon atoms, preferably 1 to 6 carbon atoms; and aryl or heterocyclic groups of 5 to 10 carbon atoms; with or without substituents selected from halogen, hydroxy, amine, acyl or carbonyl groups.
• the organic spacer group S may function to further improve the solubility of the photochromic monomer in the monomer mix, where required.
• a preferred photochromic monomer is selected from the group consisting of an ethoxy methacrylate derivative of 1,3-dihydrospiro[2H-anthra[2,3- d]imidazole-2,1'-cyclohexane]-5,10-dione, an acrylate derivative of 1,3,3- trimethyl-9'-hydroxyspiroindolinenaphthoxadine, a methacrylate derivative of 1,3,3-trimethyl-9'-(2-hydroxyethyloxy)-spiroindolinenaphthoxadine and an acrylate derivative of 1.S ⁇ -trimethyl- ⁇ '-piperidino- ⁇ '-hydroxyspiroindolinenaphthoxadine.
• a photochromic monomer having the formula
• P is a photochromic dye derivative from a photochromic dye selected from one or more of the group consisting of anthraquinones, phthalocyanines, spiro-oxazines, chromenes, pyrans including spiro-pyrans and fulgides; n is an integer of 0 to 5; m is an integer of 1 to 10;
• R 1 and R 2 which may be the same or different, are selected from hydrogen, halogen and an alkyl or substituted alkyl of 1 to 10 carbon atoms, or
• m is an aryl or heterocyclic group of 5 to 10 carbon atoms
• R 3 is selected from hydrogen, halogen, alkyl or substituted alkyl of 1 to 10 carbon atoms or alkoxy, or substituted alkoxy or 1 to 10 carbon atoms.
• R 1 , R 2 and R 3 are selected from the group consisting of hydrogen and alkyl or 1 to 5 carbon atoms.
• the photochromic monomer may function as a polymeric switch.
• the polymeric switch may be activated by the action of ultraviolet (UV) light on the photochromic dye moiety P.
• UV ultraviolet
• the photochromic monomer may have the formula wherein n and p are each integers of 0 to 5; P is a photochromic dye moiety or derivative thereof; S and S', which may be the same or different, are each an organic spacer group;
• R and R' which may be the same or different, are each a polymerisable group.
• UV light functions to activate the photochromic dye moiety P which in turn undergoes a ring opening or other stereo transformation. This will affect the bulk properties of the polymer because of the presence of P in the polymer backbone. Properties which may be affected include density, rigidity, Tg, modulus, etc., optical properties, e.g. colour, transmission, refractive index and transparency, and chemical properties, e.g. swelling or dye uptake.
• a cross ⁇ linkable polymeric casting composition including a photochromic monomer of the formula
• n and p are each integers of 0 to 5;
• P is a photochromic dye moiety or derivative thereof;
• S and S' which may be the same or different, are each an organic spacer group;
• R and R' which may be the same or different, are each a polymerisable group; a diacrylate or dimethacrylate monomer; and a polymerisable comonomer.
• the cross-linkable polymer casting composition may be utilised to produce a photochromic optical article such as an optical lens.
• the photochromic monomer may be present in amounts of from approximately 0.001 to 55% by weight, preferably approximately 0.01 to 5% by weight, based on the total weight of the casting composition. If solubility problems are encountered at higher concentrations of photochromic monomer these may be overcome by the use of spacers.
• the diacrylate or dimethacrylate monomer in the polymeric casting composition may be a polyoxyaikylene glycol diacrylate or dimethacrylate, for example a polyethylene glycol dimethacrylate with an average molecular weight of approximately 600.
• the polyoxy alkylene glycol diacrylate or dimethacrylate compound may include ethylene oxide or propylene oxide repeating units in its backbone.
• a polyethylene glycol dimethacrylate is preferred.
• One suitable material is that sold under the trade name NKESTER 9G by Shin Nakamura.
• NKESTER 9G by Shin Nakamura.
• an NK Ester 6G, 4G or 14G may be used.
• the polyoxy alkylene glycol diacrylate or dimethacrylate component may be present in amounts of from approximately 5% by weight to 60% by weight, preferably approximately 30% to 50% by weight, based on the total weight of the casting composition.
• the polymerisable comonomer may be selected to improve the properties and/or processability of the cross-linkable polymeric casting composition.
• the polymerisable comonomer may be selected from any suitable type, e.g. methacrylates, acrylates, vinyls, vinyl ethers, allyls, aromatic olefins, ethers, polythiols, epoxies and the like.
• the polymerisable comonomer may be a low viscosity comonomer.
• the low viscosity comonomer may be of any suitable type.
• the low viscosity comonomer may be selected from one or more of aromatic olefins, polymerisable bisphenol monomers capable of forming a homopolymer having a high refractive index of more than 1.55, urethane monomers having 2 to 6 terminal acrylic or methacrylic groups, and thiodiacrylate or dimethacrylate monomers.
• the aromatic olefins may be selected from styrene, divinyl benzene and 3,9-divinyl-2,4,8,10-tetraoxaspiro [5.5]undecane (DTU).
• the aromatic olefins may be present in amounts of approximately 5 to 50% by weight.
• the polymerisable bisphenol monomer may be a high index bisphenol monomer.
• the high index bisphenol monomer component in the cross-linkable casting composition may be selected from: dimethacrylate and diacrylate esters of bisphenol A dimethacrylate and diacrylate esters of 4,4'bishydroxyethoxy- bisphenol A and the like.
• Preferred high index bisphenol compounds include bisphenol A ethoxylated dimethacrylate and tetra brominated bisphenol A ethoxylated dimethacrylates.
• a bisphenol A ethoxylate dimethacrylate sold under the trade designation ATM 20 by Ancomer has been found to be suitable.
• the high index bisphenol monomer may be present in amounts of from approximately 10 to 60% by weight, preferably 20 to 55% by weight, based on the total weight of the casting composition.
• the polymerisable comonomer may include a urethane monomer having 2 to 6 terminal acrylic and/or methacrylic groups.
• Suitable materials falling within this definition include materials supplied under the trade names U-4H, U-4HA and U-6HA by Shin Nakamura, NF-201 and NF-202 by
• the urethane monomer may be present in amounts of from approximately 2.5% to approximately 35% by weight, preferably 5% to 25% by weight, based on the total weight of the casting composition.
• the thiodiacrylate or dimethacrylates may be selected from bis(4- methacryloylthioethyl)sulfide (BMTES) and bis(4-methacryloylthiophenyl)sulfide (BMTS or TS).
• BMTES bis(4- methacryloylthioethyl)sulfide
• BMTS or TS bis(4-methacryloylthiophenyl)sulfide
• the thiodiacrylate may be present in amounts of from approximately 5 to 40% by weight, preferably 20 to 40% by weight.
• cross-linkable polymeric coating composition may further include at least one poly-functional unsaturated cross-linking agent.
• the poly functional unsaturated cross-linking agent according to the present invention may be a tri- or tetra- functional vinyl, an acrylic or methacrylic monomer.
• the cross-linking agent may be a short chain monomer for example trimethylol propane trimethacrylate, pentaerythritol triacrylate or tetracrylate, or the like.
• polyfunctional cross-linking agents which may be used include NK Ester TMPT, NK Ester A-TMPT, NK Ester A-TMM-3, NK Ester A-TMMT, di- trimethylol propane tetraacrylate, trimethylolpropane triacrylate, pentaerythritrol tetramethacrylate, dipentaerythritol monohydroxypenta acrylate, pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, ethoxylated trimethylol ⁇ propane trimethacrylate.
• the polyfunctional unsaturated cross-linking agent may be present in amounts of from approximately 5 to 45% by weight, preferably approximately 30 to 40% by weight based on the total weight of the casting composition.
• the cross-linkable casting composition may further include a co-reactant including a polythiol.
• the polythiol may be selected from the group consisting of Pentaerythritol
• the thiol compound may be present in amounts from 0 to approximately 50% by weight.
• the cross-linkable casting composition according to the present invention may further include an initiator.
• the initiator may be a heat and/or ultraviolet (U.V.) initiator.
• a cationic initiator may be used where epoxies are incorporated in the composition.
• a photoinitiator preferably a long wavelength photoinitiator, may be used in combination with a cure modifier to provide a UV absorbing material.
• the amount of curing agent may vary with the monomers selected. It has been possible to operate with a relatively low level of curing agent of between approximately 0.05 and 1.5%, preferably 0.4% to 1.0% by weight. The following curing agents have been found to be suitable.
• Amicure DBU and/or Amicure BDMA are preferred.
• Initiator may be a single component or combination of initiator components.
• the photochromic optical article formed from the cross-linkable casting composition according to the present invention may be light-transmissible.
• the optical article may be transparent.
• the photochromic optical article may exhibit a high refractive index.
• the optical article may also retain good abrasion resistance and impact resistance, and reduced fatigue.
• Other additives may be present which are conventionally used in casting compositions such as inhibitors, dyes, UV stabilisers and materials capable of modifying refractive index. Mould release agents can be added but they are in general not required with the compositions used in the method of the present invention.
• Such additives may include: UV Absorbers including
• Hindered amine light stabilisers including • Ciba Geigy Tinuvin 765/292 - bis (1 ,2,2,6,6-penta- methyl-4- piperidyl)sebacate
• Ciba Geigy Irganox 245 triethylene glycol-bis-3- (3-tertbutyl-4-hydroxy-5- methyl phenyl)propionate
• Irganox 1010 2-bis[[3-[3,4-bis(1 , 1-dimethyl- ethyl)-4-hydroxyphenyl]-1- oxopropoxy]methyl]-1 ,3- propanediyl 3, 5-bis(1 , 1-dimethyl ethyl)-4-hydroxy benzene propanoate • Irganox 1076 - octadecyl 3-(3',5 , -di-tert-butyl(-4'- hydroxyphenyl) propionate Anticolourinq agents including
• monomeric additives can be present in amounts up to 10% by weight as diluents, and include monomers such as methacrylic acid, vinyl silanes, methyl allyl, hydroxy ethyl, methacrylate and materials containing hydroxy, amino and phosphine oxide groups.
• monomeric additives may be included to improve processing and/or material properties, these include:
• a photochromic optical article formed from a cross linkable casting composition including a photochromic monomer of the formula
• n and p are each integers of 0 to 5;
• P is a photochromic dye moiety or derivative thereof;
• S and S' which may be the same or different, are each an organic spacer group;
• R and R' which may be the same or different, are each a polymerisable group; a diacrylate or dimethacrylate monomer; and a polymerisable comonomer.
• the optical article may provide characteristics substantially equal to or greater than those achievable with industry standard optical articles, but with reduced stress/strain and reduced yellowing.
• the overall refractive index may be in the mid refractive index range of from approximately 1.51 to 1.57, preferably 1.53 to 1.57.
• optical articles prepared by the method of this invention include camera lenses, ophthalmic lenses and video discs.
• the casting composition may be formed into an optical article by mixing in a convenient vessel the components making up the material, and then adding the photo-initiator. The mixed material is then degassed or filtered.
• the photochromic dye moiety may be selected from one or more of the group consisting of anthraquinones, phthalocyanines, spiro-oxazines, chromenes, pyrans and fulgides.
• the photochromic dye layer or coating may exhibit reduced fatigue.
• the photochromic monomer may alternatively be incorporated in a coating applied to an optical article.
• a photochromic coating composition including a photochromic monomer of the formula
• R' ⁇ s t PP ⁇ "R (2) wherein n and p are each integers of 0 to 5; P is a photochromic dye moiety or derivative thereof; S and S', which may be the same or different, are each an organic spacer group;
• R and R' which may be the same or different, are a polymerisable group; a polymerisable co-monomer; and a solvent therefor.
• the photochromic monomer may be present in amounts of from approximately 0.5 to 25% by weight, preferably approximately 0.5 to 10% by weight, based on the total weight of the coating composition, excluding solvent.
• the photochromic coating composition may be UV curable.
• the polymerisable co-monomer may be a UV curable monomer.
• a low shrinkage monomer may be used.
• a siloxane monomer may be used, ⁇ -methacryloxypropyl trimethoxy silane has been found to be suitable.
• An acrylate-terminated oligomer may be used.
• An acrylate-terminated urethane or epoxy oligomer may be used.
• the oligomer may be selected from one or more of the following:
• Polyether acrylates may be present in amounts of from approximately 65% to 95% by weight, preferably approximately 80% to 95% by weight, based on the total weight of the coating composition, excluding solvent.
• the acrylate diluent may be included.
• the acrylate diluent may be selected from the following:
• TPGMEA Tripropylene glycol methyl ether acrylate
• the diluent may be present in amounts of from 0 to approximately 35% by weight, preferably approximately 10% to 30% by weight, based on the total weight of the coating composition, excluding solvent.
• the solvent component may be an aqueous or organic solvent.
• An organic solvent such as ethanol or toluene is preferred.
• the photochromic monomer and polymerisable co-monomer may be present in the coating composition in amounts similar to those specified above.
• a coated optical article including an optical substrate; and a polymeric coating adhered to a portion of the optical substrate, the polymeric coating being formed from a photochromic coating composition as described above.
• the polymeric coating is formed from a polymeric coating composition of the type described above.
• the optical substrate may be a lens, lens wafer, or lens blank.
• the optical substrate may be formed from the same polymeric material as, or different to, the polymeric material used in the polymeric coating.
• the polymeric material utilised in the manufacture of the lens or lens blank may be of any suitable type.
• a polycarbonate material may be used.
• An optical material of the allyl diglycol carbonate type may be used.
• the optical substrate may be formed from cross-linkable polymeric casting compositions, for example as described in applicant's United States Patent 4,912,155, United States Patent Application No. 07/781 ,392, Australian Patent Applications 50581/93, 50582/93, European Patent Specification 543149A2, or International Patent Applications PCT/AU95/00845 "Heat Responsive Articles" and PCT/AU95/00851 "Method of Preparing Photochromic Article", the entire disclosures of which are incorporated herein by reference.
• the polymeric coating may be cast on the optical article utilising front surface coating techniques.
• front surface coating techniques are described for example in Australian Patent Application 80556/87 or Australian Patent
• a commercial middle index plastic lens for example a Spectralite-type lens was dip coated in the formulation, heat dried and UV cured to give a photochromic film of good durability.
• EXAMPLE 2 An ultraviolet (UV) curable coating composition of the following formulation was prepared.
• the coating formulating was cast on a CR39-type lens utilising front surface coating techniques and UV cured. A photochromic coating of good durability was produced.
• NMR nuclear magnetic resonance
• the IR spectrum of the photochromic dye is shown in Figure 1.
• the solubility of the polymerisable dye in a standard commercial polymeric lens casting composition was improved compared with the base compound 1 ,3-dihydro-1 ,3,3-trimethylspiro[2H-indole-2,3'-[3H]phenanthr[9, 10-6] [1,4]oxazine].
• the photochromic monomer is colourless, while 1,3-dihydro-1 ,3,3- trimethylspiro[2H-indole-2,3'-[3H]phenanthr[9,10-6][1 ,4]oxazine is coloured even in the dark which limits the amount of dye which may be incorporated in a lens.
• the monomer mix was prepared in a beaker together with the TBPEH thermal initiator.
• the casting material was used to fill the space between a pair of glass moulds separated by a plastic gasket at their periphery and held together by a clip. Cure time was 8 hours with heating at a temperature of 40 to 120°C.
• the lens exhibited an improvement in thermal stability relative to comparable lenses with standard photochromic dyes of approximately 30% as discussed below.
• Example 4 was repeated, but substituting 0.1% of a Lucirin TPO photoinitiator for the TBPEH thermal initiator.
• the mould enclosing the casting material was passed four times under a UV lamp. Cure time was four hours. A satisfactory lens was again formed. The lens exhibited an improvement in thermal stability relative to comparable lenses with standard photochromic dyes of approximately 30% as discussed below.
• Example 4 was repeated with an increased level of photochromic dye monomer of 0.2%. A similar satisfactory lens, but with a deeper colour on activation, was produced. This illustrates the increased solubility of the photochromic dye monomer in the monomer mix.
• Example 1 was repeated with a UV curable coating composition of the following formulation.
• a Spectralite-type lens was dip coated in the formulation, heat dried and UV cured to give a photochromic film of good durability.
• the improved solubility of the acrylate derivative permits incorporation of increased amounts of photochromic dye via the route.
• Thermal stability of all three lenses was calculated by measuring transmittance before and after exposure of the lenses to illumination to activate the photochromic effect.
• Table 1 illustrates the increased thermal stability of the lens utilising the photochromic monomer according to the present invention.
• Example 4 was repeated substituting the methacrylate derivative of 1 ,3,3- trimethyl-9'-(2-hydroxyethyloxy)-spiroindolinenaphthoxadine prepared in Example 7 in place of the acrylate derivative of 1,3,3-trimethyl-9'- hydroxyspiroindolinenaphthoxadine.
• Example 9 was repeated substituting dye III for the photochromic monomer IV.
• Example 4 was repeated substituting the acrylate derivative of 1 ,3,3- trimethyl-9'- hydroxyspiroindolinenaphthoxadine prepared in Example 3 with the acrylate derivative of 1 ,3,3-trimethyl-6'-piperidino-9'-hydroxyspiroindoline- naphthoxadine prepared in Example 10.
• the lens exhibited an improvement in thermal stability relative to comparable lenses with standard photochromic dyes of approximately 30% as discussed below.
• Thermal stability was analysed as described in comparative Example 1 above.
• the lens of Example 10 exhibited a significantly better thermostability than the lens produced with dye V.
• the solubility of monomer VI, in the above lens formulation and in the commercial hard coating resin supplied by Toyobo, is also much better than that of dye V.

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• Optics & Photonics (AREA)
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• Health & Medical Sciences (AREA)
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• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

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• 1995
  • 1995-07-28 AU AUPN4436A patent/AUPN443695A0/en not_active Abandoned
• 1996
  • 1996-07-25 EP EP96924708A patent/EP0842236A4/de not_active Withdrawn
  • 1996-07-25 WO PCT/AU1996/000466 patent/WO1997005213A1/en not_active Application Discontinuation

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