JPH0445801B2 - - Google Patents

Description

[Detailed description of the invention]

DESCRIPTION OF THE INVENTION The present invention relates to photochromic synthetic plastic articles, sometimes photochromic optical elements such as lenses. More particularly, the present invention relates to methods of making photochromic synthetic plastic articles. Photochromism is the reversible reduction exhibited by compounds that change color upon exposure to ultraviolet light and then return to their original color or state upon removal of this ultraviolet light source. Compounds exhibiting this property are called photochromic compounds. Several methods have been used to incorporate photochromic compounds into synthetic plastic host materials. For example, US Pat. No. 3,212,898 describes the preparation of photosensitive compositions by suspending photochromic benzospiropyran in a pre-prepared polyester resin. U.S. Pat. No. 3,666,352 discloses the preparation of photochromic sunglass lenses by dispersing a mercury thiocarbazone compound in a solidified plasticized vinyl chloride-vinyl acetate copolymer and laminating the copolymer between two plastic or glass layers. Manufacture is listed. U.S. Pat. No. 3,508,810 describes the manufacture of a safety glass unit by incorporating photochromic mercury dithizonate or benzospiropyran compounds into a polyvinyl butyral membrane sealed between two glass plates of the unit. . In one embodiment, a glass plate is coated with a photochromic benzospiropyran compound, a polyvinyl butyral plastic film is placed on top of the photochromic coating, and a second glass plate is placed on top of the polyvinyl butyral film;
This composite structure was placed in an autoclave at 135°C.
Cured at a temperature of (275°F) and a pressure of 1034 kPa (150 psig). Similarly, U.S. Patent No. 3,522,143
Suitable for use as a lamina or interlayer in laminated safety glass units by kneading or mixing a photochromic metal dithizonate compound into the membrane before sheeting or by applying the potochromic material as a coating onto one surface of the membrane. The manufacture of the material is described. US Pat. No. 4,173,672 describes a decorative safety glass consisting of two glass sheets joined by a decorative film of thermoplastic polymer, such as a polyvinyl butyral film. The thermoplastic polymer is decorated by transferring the color print to the thermoplastic polymer by heat or pressure from a temporary cellulose support sheet, such as a printing paper carrying the color print made with organic or colorant-free materials. Heat and pressure are applied to the two glass sheets and the intervening decorative film until the organic or inorganic colorant is impregnated into the intervening thermoplastic film. U.S. Pat. No. 4,268,134 describes the production of lightweight laminated photochromic lenses by interposing a photochromic glass sheet between two optically clear plastic layers. US Patent No.
No. 4,289,497 describes gradient photochromics in which a photochromic material is imbibed into a lens by dipping a synthetic plastic into a solution of the photochromic compound. U.S. Pat. No. 4,286,957 utilizes conventional "thermal transfer" techniques to integrate photochromic materials into synthetic organic polymeric host materials. In this technique, a photochromic compound is applied to the surface of an organic host and then heated at 180-220°C for 30-45 seconds to integrate the photochromic substance into the host material by thermal transfer. From the published melting ranges of some of the benzospiropyrans described in this patent, the 180−
It is clear that the heating temperature of 220°C exceeds the melting temperature of such benzospiropyran. The present invention consists in the discovery of a combination of process steps which provides an advantageous method of incorporating photochromic compound(s) into synthetic plastic materials. In one embodiment of the method of the invention, a relatively thin, substantially dry, uniform film comprising a photochromic material dissolved in a carrier polymer resin is applied to at least one surface of a synthetic plastic material. Apply. The photochromic material is then incorporated into the plastic material by substantially uniformly heating the resin film at a temperature below the melting temperature of the photochromic material. The resin film depleted of photochromic material is then removed from the surface of the plastic material. The above method uses sunglasses, ski goggles,
It enables the production of photochromic plastic films, sheets, and castings useful for optical applications such as sun visors, camera lenses, optical filters, lens blanks, automobile windshields, and ophthalmic lenses. As used herein, "optical element" is intended to include lenses and transparencies. DETAILED DESCRIPTION OF THE INVENTION According to one embodiment of the method of the invention, a thin, substantially dry, homogeneous film of a polymeric organic resin having a photochromic substance, such as a spiro(indoline) type photochromic compound dissolved therein, is provided. A film is applied to at least one major surface of the synthetic plastic host material, such as a substantially flat surface. The plastic material to which the film is applied may be substantially flat or may have some degree of curvature, such as the convex and/or concave surfaces of a lens. As used herein, the term "major surface" or "flat surface" refers to one or more surfaces (flat or curved) other than the side surfaces of the host material, depending on the thickness of the plastic host material. ivy). Preferably, the membrane is applied to at least one major surface, more preferably both major surfaces, of a substantially planar prefabricated synthetic plastic host material. Application of the photochromic material-containing resin film to the receptor surface is carried out in a manner that results in a substantially uniform thickness, substantially dry, substantially mottled film or coating. Substantially free of mottling refers to droplets, bumps, streaks, or spots of solidified resin caused by uneven film thickness or uneven solvent removal;
This means that there are virtually no spots. Membrane thickness is not critical, but typically about 0.0127−0.0762mm
(0.5-3.0 mil), e.g. 0.0254-0.0508 mm (1-
2 mil). The membrane exhibits a photochromic response, i.e., a change in transmittance when exposed to ultraviolet light, in which the photochromic substance migrates out of the membrane and easily penetrates or diffuses into the interior of the plastic host material, causing the change in transmittance to be visible to the eye. It must be thin enough so that plastic articles can be made that can be seen on the screen. If the film is too thick, the temperature and time required to control the photochromic content of the photochromic material may be excessive, causing decomposition of the photochromic material. Additionally, a relatively significant amount of photochromic material remains in the thick film, placing an adverse economic burden on the process due to loss of photochromic material or by adding the cost of recovering photochromic material from spent membranes. become. The amount of photochromic material or amount of photochromic material required to achieve a visible photochromic response in the plastic host can vary and generally depends on the intensity of color change desired upon UV irradiation of the treated plastic article and the photochromic material used. Dependent. The greater the intensity of the desired color change, the greater the amount of photochromic material required. Typically, the amount of photochromic material dispersed within the plastic host is 1
For a flat surface, a photochromic response can be obtained at about ^{0.2-1 mg/in 2 .} Generally, the photochromic material is present in the resin solution in an amount of about 1.0-5% by weight, more usually about 1.5-3.5% by weight. Stated differently, in one preferred embodiment, the photochromic material comprises about 25-40% by weight of the dry solid resin film.
More preferably it constitutes 30-35% by weight. Also,
Different surfaces or even different parts or portions of the same surface may have different coating thicknesses and/or
It is also contemplated that it may have different photochromic material concentrations, thereby varying the intensity of color change in different parts of the plastic host. The polymeric resin used to form the film on the surface of the plastic host material acts as a solvent for the photochromic material, for example a spiro(indoline) type photochromic material such as spiro(indoline) naphthoxazine. The affinity between the carrier resin and the photochromic substance, i.e. the solubility of the photochromic compound in the carrier resin, should preferably not be high but should be sufficient to form a homogeneous solution at the concentrations mentioned above. . That is, the photochromic compound must be only slightly to moderately soluble in the resin so that the photochromic compound can be easily removed from the resin film. For example, if the photochromic material is infinitely or highly soluble in the resin, the driving force required to transfer the photochromic material to the plastic host will be greater than the driving force required to transfer the photochromic material to the plastic host if the photochromic material is only slightly to moderately soluble in the resin. It will be much higher than in some cases. Furthermore, the efficiency of transfer, ie the amount of photochromic material transferred (based on the total amount in the resin), will become progressively lower. Moreover, increasing the temperature of transfer to obtain higher transfer efficiency may promote thermal decomposition of photochromic materials.
However, the resin has sufficient affinity for the photochromic compound to obtain a photochromic compound concentration of, for example, 25-40% by weight in the dry resin film without crystallization or segregation of the photochromic compound in the dry resin film. must have a sexual nature. If the photochromic compound is too insoluble in the resin, it will crystallize out of the resin and form local concentrations or islands in the solid resin film. That is, a non-uniform coating is formed. When this occurs, a mottled film results, resulting in uneven transfer of the photochromic compound into the plastic article, resulting in an article exhibiting uneven color density, an undesirable result. Similarly, the resin can be easily removed from the surface of the synthetic plastic host material to which it is applied without leaving any scratches on the surface.
Must not adhere strongly to synthetic plastic host materials. Also, at the temperature at which the photochromic material migrates, the resin must remain solid and not turn into a liquid. Examples of suitable polymeric resins that can be used to form the membranes described above include polyvinyl chloride,
Polyvinyl acetate, polyurethane, polyvinyl butyral, copolymer of vinyl chloride and vinyl acetate, copolymer of vinyl chloride and vinylidene chloride, polyvinyl propionate, cessrose acetate butyrate, polymethyl acrylate, polymethyl methacrylate, polymethyl methacrylate Polymers of lower alkyl (C ₁ -C ₄ ) esters of acrylic acid and methacrylic acid such as /butyl, such as methyl ester, ethyl ester, n-butyl ester, isobutyl ester; and polyvinyl chloride and the above-mentioned polyacrylates. For example, from about 90 parts polyvinyl chloride and about 10 parts polymethyl methacrylate to about 10 parts polyvinyl chloride and about 90 parts polymethyl methacrylate. The photochromic material-containing resin is applied to the surface of the plastic host in a manner that provides a substantially dry coating to obtain a substantially mottled coating. The photochromic material-containing resin carrier medium is generally at ambient temperature,
For example, it consists of a solution of a photochromic substance-containing resin in a readily volatile organic solvent(s) at room temperature (20-22°C). Preferably the solvent is colorless. The solution generally contains about 1-5% by weight photochromic material, about 2-10% by weight resin, and about 85% by weight photochromic material.
97% by weight of solvent. Preferably, the solution comprises about 1.5% to about 3.5% by weight photochromic material, about 3% to 7% resin, and about 89.5% to 95.5% solvent. Examples of readily volatile or evaporative solvents include toluene, benzene, xylene, methyl ethyl ketone,
Methyl isobutyl ketone, methyl chloroform,
Included are acetonitrile, tetrahydrofuran, dioxane, cyclohexanone, ethyl acetate, propyl acetate, isopropyl acetate, isobutyl acetate, butyl acetate, methyl alcohol, ethyl alcohol, butanol, isopropanol, 2-methoxyethanol, acetone, and mixtures of such solvents. Preferably, the solvent is selected from toluene, methyl ethyl ketone, methyl isobutyl ketone and mixtures of such solvents. Solutions of photochromic material, resin, and solvent can be prepared in any suitable manner, for example, by independently dissolving the resin and photochromic material in a suitable solvent. The two resulting solutions are then mixed to obtain a solution of photochromic material-containing resin that is used to apply a coating to a plastic host surface. The photochromic substance-containing resin solution mentioned above is
at least one major surface of the film-receiving surface of the plastic host, such as a substantially flat Apply to the surface. Preferably, the method is such that the resulting film is substantially dry as soon as it is formed;
That is, when the resin is applied to the receptor surface of the plastic host, the easily volatile solvent is substantially volatilized.
The solution is applied in such a way that a substantially dry film is thereby left. Application methods that can be used include spraying, brushing, spin-on, dip-on, and draw-down blade.
or include the use of wire bars. Among the above methods, spraying is preferred. Spraying allows for good solvent release from the atomized droplets of the solution having a viscosity of about 1-20 centipoise, such as 5 centipoise, in one preferred manner. The viscosity of the spray solution depends on its components and the amount of each component used. More preferably, the viscosity of the solution is in the lower part of the above range, for example 1
−10 centipoise. Spraying also allows controlled application of thin coatings of substantially uniform thickness. The thickness and uniformity of the film can be controlled by the number of sprays applied to the surface and the shape of the spray exiting the spray gun. Preferably, 2 to 6 spray applications of the solution onto the receptor surface are used in preparing a relatively thin film or gold film of substantially uniform thickness and composition. In spraying methods, the high surface area of the sprayed solution allows the solvent to easily volatilize, so that the membrane is substantially dry upon application to the plastic host surface. This prevents the formation of droplets, streaks, spots, spots or other defects when the coating remains in liquid form. Prior to applying a solution of photochromic material-containing resin to a plastic host, it is preferred to clean the surface of the plastic to which the resin is applied.
Cleaning consists of washing the surface with an aqueous medium, e.g. soapy water, to remove dirt and grime, and/or with an organic solvent such as methyl chloroform or methyl ethyl ketone to remove any organic films present on the surface. This is done by washing the surface and/or removing any static charges present on the surface of the plastic material. Static charge removal can be accomplished with commercially available devices that ionize the air above the surface to create a conductive path to handle or neutralize the static charge. The surface of the plastic material to which the resin is applied is
It must be receptive to imbibition of the photochromic material during the heating process. If the receptor surface is not susceptible to imbibition, it can be treated to improve the diffusion of the photochromic material into the plastic host surface, for example by physically or chemically etching the surface. By slightly under-curing the plastic during the production of the plastic, or by adding plasticizers to the monomer material(s) used in the production of the organoplastic host.
Typically, a receptive surface can be obtained. Such methods are common in polymerization technology. After applying the photochromic material-containing resin film to the surface(s) of the plastic host material, the substantially dry film is allowed to dry completely. Drying is
It is usually carried out in air at room temperature, but when the opportunity permits drying conditions can be used to prevent crystallization of the photochromic compound within the resin film. The coated plastic article is then substantially uniformly heated at a temperature below the melting temperature of the photochromic compound used. Heating can be accomplished by any method that provides substantially uniform heating of the membrane and plastic host.
Preferably, heating is carried out in a conventional hot air circulation oven which allows uniform heating and thus a constant driving force for the transfer of the photochromic compound into the plastic host. The heating is
It can also be carried out in vacuum or using an inert atmosphere, such as a nitrogen atmosphere. The temperature to which the coated plastic article is heated depends on the melting temperature and vapor pressure of the particular photochromic compound used and the softening temperature of the synthetic plastic host. Such temperature should preferably be close to but below the melting temperature of the photochromic compound and below the softening temperature of the synthetic plastic article. Furthermore, such temperature, ie, the photochromic material migration or incorporation temperature, must be such that decomposition (thermal decomposition) of the photochromic compound is minimized. Therefore, the transition temperature selected should be sufficient to raise the vapor pressure of the photochromic compound sufficiently to allow the transfer of the photochromic compound to the plastic host without significant decomposition of the photochromic compound and softening of the plastic host. temperature. Because the melting temperature and vapor pressure of photochromic compounds, such as spiro(indoline) type photochromic compounds, vary depending on the nature of the compound and its substituents, it is not possible to provide a single temperature range that is applicable to all photochromic materials. However, given the above requirements, one skilled in the art can readily determine the appropriate temperature for heating the coated plastic article. Approximately 5 to 50 degrees higher than the melting temperature of the photochromic compound
C., preferably 5-10.degree. C. lower, is contemplated unless significant decomposition of the photochromic compound is observed at such temperatures. Generally, the temperature contemplated for use with spiro(indoline) naphthoxazine photochromic compounds and spiro(indoline) pyridobenzoxazine photochromic compounds is from about 145 to about 160°C. In particular, photochromic compounds: 1,3,3,
5,6,-Pentamethyl-9'-methoxyspiro[indolino-2,3'[3H]-naphtho[2,1-
b] [1,4]oxazine], 1,3,5,6-tetramethyl-3-ethylspiro[indoline-
2,3′[3,H]pyrido[3,2-f][1,4]
benzoxazine], 1,3,3,4,5-(or 1,3,3,5,6-pentamethylspiro[indoline-2,3'[ 3H ]pyrido[3,2- f ]
About 145 for [1,4]benzoxazine]
- a temperature of about 155°C, for example 150-155' is contemplated. The coated plastic article is held at the transition temperature for a sufficient period of time to cause a substantial amount of the photochromic compound to diffuse into and subsurface the surface of the plastic article. Typically, the heating time is about 15 to about 60 minutes, usually about 20 to about 45 minutes at the transition temperature. For the above photochromic benzoxazine compound, heating for 25 to 30 minutes is appropriate. The exact mechanism by which the photochromic compound migrates into the plastic host material from the resin film adhered to the surface of the plastic host material is not known. It is hypothesized that migration can be accomplished by thermal diffusion, sublimation, condensation, or a combination of these mechanisms. Whatever the special mechanism(s), the photochromic compound penetrates into the interior of the plastic substrate, usually into its surface area, and becomes permanently and firmly embedded within the plastic host material. (incorporated) In this manner, a photochromic quantity of photochromic material is transferred substantially uniformly into and across the flat surface of the plastic host. After transfer of the photochromic compound into the plastic article, the coated plastic is cooled, eg, to room temperature, and the residual resin film, which has a reduced concentration of photochromic material, is then removed from the surface of the plastic host. Removal of the photochromic compound consumable film can be carried out in any suitable manner, preferably in a manner that does not impair the optical quality of the surface of the plastic host. Typically, consumable membranes include methyl chloroform, trichloroethylene, methyl ethyl ketone,
Methyl isobutyl ketone, methyl ethyl ketone
It is stripped from the plastic substrate by contacting the membrane with a suitable organic solvent such as toluene mixtures, or other solvents such as acetone, ethylene dichloride, chloroform, chlorobenzenes. The same solvent used to prepare the photochromic material-containing resin solution can be used to remove the residual resin film. A suitable method of contacting the membrane with an organic solvent involves exposing the membrane to vapors of the selected solvent(s) and allowing the vapors to condense and flow down onto the surface of the plastic material, thereby forming a photochromic material-consumable resin membrane. This is done using a vapor degreasing device that cleans the surface from the surface. Alternatively,
The resin film can be removed by dipping the plastic substrate in a solvent bath, spraying the film with a solvent, or physically peeling the film from the substrate. After the photochromic compound consumable or used film is removed from the surface of the plastic article, the surface can be washed with water or other suitable aqueous medium, such as a soap or detergent solution, and dried. If desired, the plastic articles can be colored by methods known in the art, such as conventional disperse and soluble dyes used in the coloring of organic plastic materials using conventional dye baths. Thereafter, the colored plastic article is washed, for example with soapy water, and dried. Coloring of the plastic material can be carried out immediately after removal of the used resin film and before cleaning with an aqueous medium. Alternatively, the coloring can be applied before applying the photochromic compound. Synthetic plastic host materials that can be used in the method of the invention are solid, transparent, polymeric organic materials. Preferably, the host material is an optically transparent material, ie, a material suitable for ophthalmic or optical devices, such as ophthalmic lenses, or useful for applications such as windows, windshields, etc. Examples of transparent host materials for use with the photochromic compounds of the present invention include polymers and copolymers of polyol (allyl carbonate) monomers, polyacrylates, poly(alkyl acrylates) such as polymethyl methacrylate, cellulose acetate, cellulose propionate, butyric acid. Cellulose, triacetylcellulose, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), polyurethane, polyethylene terephthalate, polystyrene, poly(styrene-methyl methacrylate) copolymer, poly(styrene-acrylonitrile) Copolymers, polyvinylpyrrolidone, polyvinyl chloride, polyvinyl butyrate, polyvinyl butyral. Transparent polymers and transparent blends of copolymers are also suitable as host materials. Preferably, the host material is a polycarbonate such as poly(4,4'-dioxydiphenol-2,2-propane) sold under the trademark LEXAN; a polyol (allyl carbonate), especially CR- Polymers of diethylene glycol bis(allyl carbonate) sold under the trademark 39 and their copolymers, e.g. Allyl carbonate) 80
-85% and vinyl acetate 15-20%; cellulose acetate, cellulose propionate, cellulose butyrate; polyethylene and its copolymer with methyl methacrylate, vinyl acetate, acrylonitrile; optically transparent made from cellulose acetate butyrate It is a polymeric organic material. Polymethyl methacrylate, such as the material sold under the trademark PLEXIGLAS, can also be used with photochromic materials having melting points below about 140°C. Polyol (allyl carbonate) monomers that can be polymerized to produce transparent host materials include allyl carbonates of linear or branched aliphatic liquid polyols or aromatic liquid polyols, such as aliphatic glycol bis(allyl carbonate) compounds. or an alkylidene bisphenol bis(allyl carbonate) compound. These monomers can be described as unsaturated polycarbonates of polyols such as glycols. These monomers are made by methods known in the art, such as those of US Pat. Nos. 2,370,567 and 2,403,113. Polyol (allyl carbonate) monomer has the formula (In the above formula, R is a group derived from an unsaturated alcohol, usually an allyl or substituted allyl group, and R' is a group derived from a polyol,
n is an integer from 2 to 5, preferably 2)
It is indicated by. The allyl group (R) may be substituted in the 2-position by a halogen, especially chlorine or bromine, or an alkyl group containing 1 to 4 carbon atoms, generally a methyl or ethyl group. The R group is of the formula
(In the above formula, R ₀ is hydrogen or halogen or
C ₁ -C ₄ alkyl group). Special examples of R include allyl group, 2-
Included are chloroallyl group, 2-bromoallyl group, 2-fluoroallyl group, 2-methallyl group, 2-ethylallyl group, 2-isopropylallyl group, 2-n-propylallyl group, and 2-n-butylallyl group. Most commonly R is an allyl group, _H2C =CH- _CH2
− is. R′ is a polyvalent group derived from polyol,
The polyols can be aliphatic or aromatic polyols and contain 2 or 3 or 4 or 5 hydroxy groups. Typically, polyols contain two hydroxy groups, ie, glycols or bisphenols.
Aliphatic polyols can be linear or branched and contain 2-10 carbon atoms. Usually aliphatic polyols are alkylene glycols having 2-4 carbon atoms or poly( _C2 - _C4 ) alkylene glycols, i.e. ethylene glycol,
These include propylene glycol, trimethylene glycol, tetramethylene glycol, diethylene glycol, and triethylene glycol. Aromatic polyols have the formula (In the above formula, A is a divalent group derived from an acyclic aliphatic hydrocarbon, such as an alkylene or alkylidene group having 1-4 carbon atoms, such as methylene, ethylene, dimethylmethylene (isopropylidene) , R _a represents a lower alkyl substituent of 1-3 carbon atoms, and p is an integer of 0 or 1 or 2 or 3. Preferably, the hydroxyl group is in the ortho or para position. . A special example of the group R′ is ethylene (−CH ₂ −
CH ₂ −), trimethylene, methylethylene, tetramethylene, ethylethylene, pentamethylene,
Alkylene groups containing 2-10 carbon atoms such as hexamethylene, 2-methylhexamethylene, octamethylene, decamethylene; -CH ₂ -O-CH ₂
−, −CH ₂ CH ₂ −O−CH ₂ CH ₂ −, −CH ₂ −O−
CH ₂ −CH ₂ −, −CH ₂ CH ₂ CH ₂ −O−
Alkylene ether groups such as CH ₂ CH ₂ CH ₂ −;
-CH ₂ -CH ₂ -O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -,
−CH ₂ CH ₂ CH ₂ −O−CH ₂ CH ₂ CH ₂ −O−
Alkylene polyether groups such as CH ₂ CH ₂ CH ₂ -; -CH ₂ CH ₂ -O-CO-O-CH ₂ CH ₂ -, -
CH ₂ CH ₂ -O-CH ₂ CH ₂ -O-CO-O-
alkylene carbonate and alkylene ether carbonate groups such as _CH2CH2 -O _{- CH2CH2-} ; and isopropylidene bis(paraphenyl ₎ i.e. is included. _Most commonly _, R' _{is -CH2CH2-} or _{-CH2CH2 -} O- _CH2CH2- or _-CH2CH2-
O- _{CH2CH2 - O} - _CH2CH2- . Specific examples of polyol (allyl carbonate) monomers include ethylene glycol bis(2-chloroallyl carbonate), ethylene glycol bis(allyl carbonate), diethylene glycol bis(2-methallyl carbonate), diethylene glycol bis(allyl carbonate), triethylene glycol bis(allyl carbonate), Ethylene glycol bis(allyl carbonate), propylene glycol bis(2-ethylallyl carbonate), 1,3-propanediol bis(allyl carbonate), 1,3-butanediol bis(allyl carbonate), 1,4-butanediol bis (2-bromoallyl carbonate), dipropylene glycol bis(allyl carbonate), trimethylene glycol bis(2-
ethyl allyl carbonate), pentamethylene glycol bis(allyl carbonate), and isopropylidene bisphenol bis(allyl carbonate). The industrially important polyol bis(allyl carbonate) monomers that can be used in the invention contemplated herein are It is. Diethylene glycol bis(allyl carbonate) is preferred. Due to the method of preparation of polyol (allyl carbonate) monomers, i.e. by phosgenation of the polyol (or allyl alcohol) and subsequent esterification with the allyl alcohol (or polyol), respectively, the monomer product contains allyl carbonate group-binding moieties. may include related species containing one or more carbonate groups. These related species are represented by the formula (In the above formula, R is as defined above,
R _b is a divalent group derived from a diol, such as alkylene or phenylene, and s is an integer from 2 to 5. Related species of diethylene glycol bis(allyl carbonate) have the formula (In the above formula, s is an integer of 2-5.) The polyol (allyl carbonate) monomer may typically contain 2-20% by weight of related species, such related species as a mixture, i.e., the related species indicated by s equal to 2, 3, 4, etc. Can exist as a mixture of species. Photochromic substances contemplated for use in the method of the invention are compounds containing spiro(indoline) type compounds that give a visible photochromic response, are moderately soluble in the resins mentioned above,
It is soluble in the plastic host and, as mentioned above, can be readily transferred from the film on the plastic host surface to the plastic host by application of heat without significant decomposition at temperatures close to but below its melting temperature. It is a migratable compound. The particularly intended hot cromitz substance is less than 600, for example, spiro (Indrin) pilidobenzooxazine, spillo (Indrin) benzopilan, spillo (Indrin) nappiran, spillo (indoline) mine pyran, spillo (indoline) kinopilan, spillo (Indrin) ) Benzoxazine, Spiro(Indoline) Pyridopyran, Spiro(Indoline)
It is pyridoxazine. Preferred photochromic materials are the pyridobenzoxazines and naphthoxazines mentioned above. Spiro (indoline) contemplated in the present invention
Pyridobenzoxazine can be represented by the following formula. In the above formula, R ₁ is hydrogen, C ₁ -C ₈ alkyl, such as methyl, ethyl, propyl, butyl, phenyl, phenyl (C ₁ -C ₄ ) alkyl, allyl,
and mono- and di-substituted phenyl,
The phenyl substituents are C ₁ -C ₄ alkyl and C ₁ -
_C5 alkoxy, such as ethoxy, propoxy,
Selected from the group consisting of substituted phenyl selected from butoxy and pentoxy. Preferably R ₁ is hydrogen or C ₁ -C ₄ alkyl or phenyl or benzyl group. R ₂ and R ₃ in the formula are each hydrogen, C ₁ −
selected from the group consisting of C ₅ alkyl, phenyl, mono- and di-substituted phenyl, benzyl;
Alternatively, they are combined to form a cyclic ring selected from the group consisting of an alicyclic ring containing 6-8 carbon atoms (including spiro carbon atoms), norbornyl, and adamantyl. Phenyl substituents can be chosen from _C1 - _C4 alkyl and _C1 - _C5 alkoxy groups.
Preferably, R ₂ and R ₃ are each methyl,
Selected from _C1 - _C5 alkyl such as ethyl.
When one of R ₂ and R ₃ is a tertiary alkyl group such as tert-butyl or tert-amyl, the other is preferably an alkyl group other than a tertiary alkyl group. In the formula, R ₄ and R ₅ are each hydrogen, C _1
-C5 alkyl, halogen, _C1 - _C5 alkoxy,
Nitro, cyano, _C1 - _C4 haloalkyl, _C1 - _C4
selected from polyhaloalkyl, _C1 - _C8 alkoxycarbonyl. R ₄ and R ₅ can be present on any two available carbon atoms of the indoline portion of the compound, ie, the 4- or 5- or 6- or 7-position carbon atoms. Preferably, when the substituent is other than hydrogen, the substituent is located at the 4- and 5-positions, or at the 5- and 6-positions, or at the 4- and 7-positions.
It exists in the 6th and 7th positions. Regarding halogen or haloalkyl substituents, any halogen can be used, ie chlorine, bromine, iodine, fluorine, with chlorine, bromine, trifluoromethyl being preferred. Preferably R ₄ and R ₅ are hydrogen,
C1 _{- C2} alkyl, such as methyl, ethyl, chlorine,
selected from the group consisting of bromine, _C1 - _C5 alkoxy, such as methoxy, ethoxy. Photochromic materials of particular interest are those in which R ₁ is methyl, ethyl, n-propyl, isopropyl,
C ₁ -C ₄ alkyl such as n-butyl, sec-butyl, isobutyl, tert-butyl and R ₂ and
A photochromic compound represented by the formula in which each of R ₃ is methyl, ethyl, or phenyl, and each of R ₄ and R ₅ is hydrogen, methyl, methoxy, or chloro. The spiro(indoline)pyridobenzoxazines mentioned above can be synthesized by reacting the corresponding nitrosohydroxyquinoline compounds with the corresponding free indolines (Fitscher's bases) or indolium salts, e.g. chloride salts. . Both precursor materials are refluxed in a suitable solvent such as toluene or isopropanol until the reaction is complete. When used as a reaction component of the indolium salt, a base such as triethylamine is present in the reaction medium. See, for example, European Patent Application No. 841113167.5, which describes the above-mentioned pyridobenzoxazines and their synthesis. Examples of suitable spiro(indoline)pyridobenzoxazines include compounds where R ₁ , R ₂ , R ₃ , R ₄ , R ₅ are as shown in the table below.

[Table] Compound 2 in the table is 1,3,3,4,5-
(or 1,3,3,5,6-)pentamethylspiro[indoline-2,3'[3H]pyrido[3,2
-f ][1,4]benzoxazine]. Similarly, compound 6 in the table is
1,3,5,6-tetramethyl-3-ethylspiro(indoline-2,3'[ 3H ]pyrido[3,2
-f ][1,4]benzoxazine]. Other compounds in the table can be similarly named taking into account different substituents. Spiro (indoline) contemplated in the present invention
Naphthoxazine is represented by the following formula XI. Spiro(indoline)naphthoxazines and their synthesis are described, for example, in U.S. Pat.
It is described in No. 3578602 and No. 4215010. In formula XI, R′ ₁ is hydrogen and C ₁ -C ₈ alkyl,
For example, it can be selected from methyl, R′ ₂ and R′ ₃ are
each hydrogen, _C1 - _C5 alkyl, phenyl, typically _C1 - _C2 alkyl such as methyl, ethyl; _R'4 , _R'5 is each hydrogen _C1 - _C5 alkyl, halogen such as chlorine or bromine, nitro, cyano, _C1 - _C5 alkoxy,
It can be selected from _C1 - _C5 alkoxycarbonyl, and _R'6 , _R'7 can each be selected from hydrogen, halogen, such as chlorine, bromine, _C1 - _C4 alkoxy. Spiro (indoline) contemplated in the present invention
Particular examples of naphthoxazines include the substituent R′ ₁ −
Included are compounds in which R' ₇ is as shown in the table below.

[Table] Compound 2 in the table is 1,3,3,5,6-pentamethyl-9'-methoxyspiro[indoline-
It can be named 2,3'[3H]-naphtho[2,1-b][1,4]oxazine]. Similarly, compound 6 in the table is 1,3,5,6-tetramethyl-3-ethyl-9'-methoxyspiro[indoline-2,3'[3H]-naphtho[2,1-b][ 1,
4] Oxazine]. Other compounds in the table can be named taking into account different substituents. Spiro(indoline)benzopyrans contemplated for use in the present invention include compounds of formula XII: Spiro(indoline)benzopyrans are known in the art. These benzopyrans and their synthesis are described in U.S. Pat.
3346385 as well as UK Patent No. 1418089. In formula XII, R″ ₁ can be hydrogen or C ₁ -C ₄ alkyl, and R″ ₂ , R″ ₃ are each hydrogen,
can be _C1 - _C5 alkyl, phenyl, _C1 - _C2 alkyl such as methyl, ethyl;
R″ ₄ and R″ ₅ each represent hydrogen, halogen such as chlorine or bromine, _C1 - _C4 alkyl, nitro,
can be cyano, _C1 - _C4 alkoxy,
R″ ₆ and R″ ₇ are hydrogen, _C1 - _C4 alkoxy,
It can be chosen from nitro, phenyl, halogens such as chlorine or bromine. Examples of spiro(indoline)benzopyran include
1,3,3-trimethyl-6'-nitro-spiro (2H-1-benzopyran-2,2'-indoline);1,3,3-trimethyl-6'-nitro-
8'-Methoxy-spiro(2H-1-benzopyran-2,2'-indoline);1,3,3-trimethyl-6'-nitro-8'-bromo-spiro (2H-1
-benzopyran-2,2'-indoline); 1,
3,3-trimethyl-5'-bromo-6'-nitro-
8'-Methoxy-spiro (2H-1-benzopyran-2,2'-indoline);1,3,3-trimethyl-5-chloro-6'-nitro-spiro (2H-
1-benzopyran-2,2'-indoline); 1-
Includes phenyl-3,3-dimethyl-6'-nitro-spiro (2H-1-benzopyran-2,2'-indoline). Spiro(indoline)naphthopyran and spiro(indoline)quinopyran are represented by the following formulas. In the above formula, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ are represented by the formula
As explained above, R ₆ and R ₉ each represent hydrogen, C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy,
It can be chosen from nitro, halogen such as chlorine or bromine, Y being carbon or nitrogen respectively. Examples of spiro(indoline)naphthopyran include
1,3,3-trimethylspiro[indoline-
2,2′-[2H]-naphtho[1,2-b]pyran];
1,3,3,5,6-pentamethyl-spiro[indoline-2,2'-[2H]-naphtho[1,2-b]
pyran]; 1,3,3-trimethyl-5-methoxy-spiro[indoline-2,2'-[2H]-naphtho[1,2-b]pyran];1,3,3-trimethyl-6'- Chloro-spiro [indoline-2,
2′-[2H]-naphtho[1,2-b]pyran]; 1,
Includes 3,3-trimethyl-6'-nitro-spiro[indoline-2,2'[2H]-naphtho[1,2-b]pyran]. Examples of spiro[indoline]quinopyran include spiro[2H-indole-2,3'-[3H]pyrano[3,2-f]quinoline; 1,3,3-trimethylspiro[2H-indole-2,3 '-[3H]pyrano[3,2-f]quinoline; 1,3,3,5,
6-pentamethylspiro [2H-indole-2,
3′-[3H]pyrano[3,2-f]quinoline; 1,
3,5,6-tetramethyl-3-ethylspiro[2H-indole-2,3'-[3H]pyrano[3,
2-f]quinoline; 1,3,3-trimethyl-5
-methoxyspiro[2H-indole-2,3'-
[3H] Pyrano[3,2-f]quinoline; 5-chloro-1,3,3,6'-tetramethylspiro[2H
-indole-2,3′-[3H]pyrano[3,2-
f] Contains quinoline. Spiro(indoline)-benzoxazine, -pyridopyran, -pyridoxazine is represented by the following formula. In the above formula, R ₁ , R ₂ , R ₃ , R ₄ , and R ₅ are as described for formula X, and Z and Y are nitrogen and carbon, carbon and nitrogen, and nitrogen and nitrogen, respectively,
R ₆ and R ₉ are as explained in relation to the formula. According to the present invention, a polymer of diethylene glycol bis(allyl carbonate) or diethylene glycol bis(allyl carbonate) and 10-
Polymerization of organoplastic host materials such as copolymers or polycarbonates with 20% vinyl acetate is degreased with organic solvents such as methyl ethyl keltone to provide a clean surface. The static charge is removed from the cleaned surface by passing a high voltage discharge brush over the cleaned surface. Next, spiro(indoline) in a readily volatile organic solvent
applying a solution of a spiro(indoline) type photochromic material, such as pyridobenzoxazine, and polyvinyl chloride resin to a cleaned and substantially static charge-free plastic host surface(s);
For example, by spraying the solution onto the surface(s), apply a very thin layer of polymer resin containing about 30-35% photochromic material, e.g. about 0.0127-0.0762 mm thick ( 0.5-3 mil) to form a substantially dry coating or film. The surface-coated plastic host is then heated in a heating zone for about 10-60 min at a temperature below the melting temperature of the photochromic material.
2 minutes, thereby transferring the photochromic material from the polymer resin coating into the subsurface region of the plastic host. After cooling, the film is removed by contacting the photochromic material-depleted polymer resin film with an organic solvent such as methyl ethyl ketone. The photochromic treated plastic host is optionally colored with a conventional dye that is complementary to the color of the photochromic material. Thereafter, the surface is washed with soapy water to remove dye and organic solvent residues, and the article is dried. next,
The photochromic (and optionally colored) plastic is molded into a lens-like shape by known molding methods, such as thermoforming. Thermoforming is a heat treatment of the lens in which a lens, for example a flat lens, is placed on a female mold whose geometry corresponds, for example, to a small circular segment of a sphere with a radius of 9 cm, the lens is heated and pressed against the female mold for several minutes. This is a method of deforming a flat lens into a concave shape. The present invention will be explained in detail below with reference to Examples. These examples are for illustrative purposes only, as numerous modifications and changes in the examples will be apparent to those skilled in the art. EXAMPLE A sprayable photochromic material-containing solution was prepared by dissolving 1 part photochromic compound in 17 parts methyl ethyl ketone and 17 parts toluene. 2 parts polyvinyl chloride resin (Strip Coat 2253 from 3M Company)
was dissolved in about 9 parts of an 80/20 toluene-methyl isobutyl ketone mixture. Both resulting solutions were mixed and sprayed with a regular air atomization spray gun into a 2.54 cm (1 in) x 5.08 cm (2 in) x 0.32 cm made from diethylene glycol bis(allyl carbonate).
(0.125in) solid plastic coupons. Application of the solution to the coupon was done using four consecutive coats. The entire surface area of the coupon was coated multiple times to obtain the highest film uniformity. The resulting film was substantially dry upon application to the coupon. Allow the membrane to dry completely and remove the coated coupon.
Heat in a circulating air oven at 160°C for 20 minutes. After cooling, the photochromic material consumable film is
Removed with acetone or methyl ethyl ketone. This coupon, which has a photochromic compound imbibed inside, is exposed to a xenon high-pressure arc light.
Irradiation was performed at a UV energy level of 3.0 mW/cm ² . An OX-1 filter was attached to the arc lamp. The optical density change (ΔOD) during 30 seconds illumination and 4 minutes (saturated) illumination was measured using a radiometer.
Measured with a meter). Ultraviolet absorbance at 347 nm (λ _nax ) was also measured with a spectrophotometer. These data are shown in the table.

TABLE The data in the table demonstrate that the method of the present invention is effective for incorporating photochromic compounds into synthetic plastic host materials. Above, the present invention has been described in particular with respect to spiro(indoline) pyridobenzoxazone and spiro(indoline) naphthoxadiphotochylomic material and a polymer of diethylene glycol bis(allyl carbonate) as a plastic host. substituting the indoline type photochromic material with other photochromic materials described herein and substituting the polymer of diethylene glycol bis(allyl carbonate) with other plastic host materials described herein; It is expected that substantially similar results will be obtained. Although the invention has been described with respect to specific details of some embodiments thereof, such details are not to be construed as limitations on the scope of the invention other than as contained in the claims.

Claims (1)

Claims: 1. (a) a substantially spotless, substantially uniform film of a polymeric resin having a photochromic substance dissolved therein;
(b) applying a photochromic amount of the photochromic material into the subsurface of the plastic article at a temperature near but below the melting temperature of the photochromic material; A method for imparting photochromic responsiveness to a synthetic plastic article, comprising the steps of: heating for a sufficient period of time to incorporate; and (c) removing a photochromic material-depleted film from the surface of the plastic article. 2. The method of claim 1, wherein the membrane has a thickness of about 0.5 to 3 mils. 3. The method of claim 2, wherein the photochromic material comprises about 25-40% by weight of the dry film applied to the surface of the plastic article. 4. The method of claim 1, wherein the film is applied by spraying a solution of the photochromic material and polymeric resin in a readily volatile solvent onto the major surface(s) of the plastic article. 5. The method of claim 4, wherein the film is substantially dry as soon as it is applied. 6. The method of claim 1, wherein the viscosity of the solution is about 1-20 centipoise. 7. The method of claim 1, wherein the major surface (at least one) is clean and substantially free of static charge. 8. The method of claim 1, wherein the temperature at which the membrane-supported plastic article is heated is about 5 DEG C. to 50 DEG C. below the melting temperature of the photochromic material. 9. The method of claim 1, wherein the heating time is about 15 minutes to 60 minutes. 10. The method of claim 1, wherein the photochromic quality deficient film is removed from the surface by welding with an organic solvent. 11. The method according to claim 1, wherein the photochromic substance is a spiro(indoline) type photochromic compound. 12. The method of claim 11, wherein the photochromic substance is a spiro(indoline)pyridobenzoxazine or a spiro(indoline)naphthoxazine. 13. Plastic articles are polymers and copolymers of polyol (allyl carbonate) monomers, polyacrylates, poly(alkyl acrylates), cellulose acetate, cellulose triacetate,
From cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), polyurethane, polycarbonate, polyethylene terephthalate, polystyrene, poly(styrene-methyl methacrylate), poly(styrene-acrylonitrile) and polyvinylbrylal The method of claim 11 selected. 14 The plastic article is a polymer of diethylene glycol bis(allyl carbonate), a copolymer of diethylene glycol (allyl carbonate) and vinyl acetate, polycarbonate, polyvinyl butyral, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, polystyrene, styrene and methacrylate. Claim 11 selected from copolymers with methyl acid or vinyl acetate or acrylonitrile.
The method described in section. 15. The method of claim 14, wherein the photochromic substance is spiro(indoline)pyridobenzoxazine or spiro(indoline)naphthoxazine. 16. The method of claim 15, wherein the membrane has a thickness of about 0.5 to 3 millimeters. 17. The method of claim 16, wherein the photochromic material comprises about 25-40% by weight of the dry film applied to the surface of the plastic article. 18. The method of claim 16, wherein the film is applied by spraying a solution of the photochromic material and polymeric resin in a readily volatile solvent onto the major surface(s) of the plastic article. 19 The temperature at which the membrane-supported plastic article is heated is approximately 5°C to 50°C below the melting temperature of the photochromic material.
The method of lower claim 18. 20. The method of claim 19, wherein the heating time is about 15 minutes to 60 minutes. 21 The temperature at which the membrane-supported article is heated is approximately 145°C to 160°C.
20. The method according to claim 19, wherein the temperature is .degree. 22 Claim 20 also includes the step of coloring the plastic article with a complementary dye after removing the photochromic depletion film from the surface of the plastic article.
The method described in section. 23. The method of claim 20, wherein the plastic article is colored with a complementary dye before the photochromic material-containing film is applied to the surface of the article. 24 (a) applying a substantially mottled, substantially uniform film of a polymeric resin having a spiro(indoline) type photochromic material dissolved therein on at least one major surface of a synthetic plastic article; the film has a substantially uniform thickness over a portion of the surface of the plastic article to which it is applied and is substantially dry once applied, and the polymeric resin is (b) coating the film-bearing plastic article at a temperature close to but at a melting temperature of the photochromic material, which is a solvent for the photochromic material and remains solid at the incorporation temperature of step (b); (c) heating at a lower temperature for a time sufficient to incorporate a photochromic amount of photochromic material into the surface of the plastic article; 1. A method of imparting photochromic responsiveness to a synthetic plastic article, the method comprising the step of: removing it from the surface. 25. The method of claim 24, wherein the membrane has a thickness of about 0.5 to 3 mils. 26. The method of claim 25, wherein the membrane has a thickness of about 1-2 mils. 27. Applying a film by spraying a solution of a photochromic substance and a polymeric resin in a readily volatile solvent onto the surface (at least one) of the plastic article, and the solution containing 25-40% by weight of the photochromic substance. 26. The method of claim 25, comprising sufficient photochromic material to produce a dry film. 28 5°C higher than the melting temperature of photochromic substances
28. The method according to claim 27, wherein the heating time at a temperature 50°C lower is 15 to 60 minutes. 29 (a) Where the plastic articles are polymers and copolymers of polyol (allyl carbonate) monomers, polyacrylates, poly(alkyl acrylates), cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), selected from poly(vinyl alcohol), polyurethane, polycarbonate, polyethylene terephthalate, polystyrene, poly(styrene-methyl methacrylate), poly(styrene-acrylonitrile), polyvinyl butyral, and (b) the photochromic substance is spiro(indoline).
Pyridobenzoxazine, Spiro(Indoline) Naphthoxazine, Spiro(Indoline)
selected from benzopyran, spiro(indoline)naphthopyran, spiro(indoline)quinopyran, spiro(indoline)benzoxazine, spiro(indoline)pyridopyran, spiro(indoline)pyridoxazine, and (c) the polymer resin is polyvinyl chloride, polyvinyl chloride, Vinyl acetate, polyurethane, polyvinyl butyral,
Copolymers of vinyl chloride and vinyl acetate, copolymers of vinyl chloride and vinylidene chloride, vinyl propionate, cellulose acetate butyrate, polymers of _C1 - _C4 esters of acrylic acid or methacrylic acid, polyvinyl chloride and the acrylic acid A mixture containing 10 to 90 parts of polyvinyl chloride and 90 to 10 parts of an acrylic acid ester polymer is selected. The method according to claim 25. 30 (a) the plastic article is a polymer of diethylene glycol bis(allyl carbonate);
selected from copolymers of diethylene glycol bis(allyl carbonate) and vinyl acetate, polycarbonate, polyvinyl butyral, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, polystyrene, copolymers of styrene and methyl methacrylate or vinyl acetate or acrylonitrile, and (b) the photochromic substance is spiro (indoline).
pyridobenzoxazine, spiro(indoline)naphthoxazine, and (c) the polymer resin is polyvinyl chloride, polyvinyl acetate, polyvinyl butyral, copolymer of vinyl chloride and vinyl acetate, polyvinyl propionate, cellulose acetate butyrate. , polymethyl acrylate, polymethyl methacrylate, a mixture of polyvinyl chloride and the acrylic ester polymer, comprising 10 to 90 parts of polyvinyl chloride and 90 to 10 parts of the acrylic ester polymer 30. The method of claim 29, wherein the method is selected from mixtures. 31 Apply a film by spraying a solution of a photochromic material and a polymeric resin in a readily volatile organic solvent onto the surface(s) of a plastic article, and the solution contains 25-40% by weight of the photochromic material. Claim 30 comprising sufficient photochromic material to produce a dry film comprising:
The method described in section. 32 The temperature at which the membrane-supported plastic article is heated is approximately 5°C to 50°C below the melting temperature of the photochromic material.
32. The method of claim 31, wherein the temperature is low and the heating time is about 15 minutes to 60 minutes. 33 The temperature and time for heating the membrane-supported plastic article are 145°C to 160°C and 20 minutes to 45°C, respectively.
33. The method of claim 32, wherein the method is: