U.S. patent application number 08/913620 was filed with the patent office on 2002-04-25 for photochromic spiropyrans, and compositions and articles containing same.
Invention is credited to CHAN, YOU-PING, SOULA, GERARD.
Application Number | 20020049341 08/913620 |
Document ID | / |
Family ID | 9477570 |
Filed Date | 2002-04-25 |
United States Patent
Application |
20020049341 |
Kind Code |
A1 |
SOULA, GERARD ; et
al. |
April 25, 2002 |
PHOTOCHROMIC SPIROPYRANS, AND COMPOSITIONS AND ARTICLES CONTAINING
SAME
Abstract
Novel spiropyran compounds, particularly with photochromic
properties, are disclosed, as well as photochromic compositions and
ophthalmic articles (e.g. lenses) containing said compounds. The
photochromes have been designed so as to have a high colorability,
a high sensitivity to activating radiation breaking the pyran ring,
to be entirely or practically free from coloration in a non
activated (non exposed) state, to have an intense coloration
following activation and a high coverage of the visible spectrum in
combination with at least one other photochrome, and to have high
rates of coloration/decoloration. The spiropyrans are easily
produced and photochemically stable, and are, e.g., of formula (i),
wherein L=(a);(b).
Inventors: |
SOULA, GERARD; (MEYZIEU,
FR) ; CHAN, YOU-PING; (LYON, FR) |
Correspondence
Address: |
BACON & THOMAS
625 SLATERS LANE
4TH FLOOR
ALEXANDRIA
VA
22314
|
Family ID: |
9477570 |
Appl. No.: |
08/913620 |
Filed: |
November 14, 1997 |
PCT Filed: |
March 21, 1996 |
PCT NO: |
PCT/FR96/00429 |
Current U.S.
Class: |
549/331 ;
549/381; 549/456; 549/472; 549/473 |
Current CPC
Class: |
C09K 9/02 20130101; C08K
5/1545 20130101; C07D 311/96 20130101 |
Class at
Publication: |
549/331 ;
549/381; 549/456; 549/472; 549/473 |
International
Class: |
C07D 321/10 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 24, 1995 |
FR |
95-03 739 |
Claims
1. Compound, particularly photochromic compound, of the following
general formula (I): 29in which: R.sup.2, R.sup.3, R.sup.4,
R.sup.5, R.sup.6 and R.sup.7 are identical or different and are:
hydrogen, an alkyl, cycloalkyl, alkenyl, alkynyl, aryl or
heteroaryl group (preferably phenyl or naphthyl mono-, di- or
tri-substituted by donor or acceptor groups) or an aryloxy or
aralkyl group, said group optionally being halogenated, a halogen,
preferably F, Br or Cl, OR, SR, --OCOR or --COOR, where R.dbd.H,
alkyl and/or cycloalkyl and/or aryl, a (poly)ether, a (poly)amide,
a (poly)carbonate, a (poly)carbamate, a (poly)urea or a
(poly)ester, an amino radical which--once bonded in (I)--produces a
primary, secondary or tertiary amine, said amine being
monosubstituted or disubstituted by alkyl, aryl or aralkyl,
depending on its type, or a cyclic amino radical optionally
containing one or more heteroatoms, or an electron-attracting group
preferably selected from the group comprising CF.sub.3, CN,
NO.sub.2 and SCN, at least two of the radicals R.sup.4, R.sup.5,
R.sup.6 and R.sup.7, preferably carried by two vicinal carbons, can
optionally form at least one aromatic or aliphatic ring
advantageously having from 4 to 7 ring members and even more
advantageously having five or six ring members, said ring(s)
optionally comprising at least one heteroatom so as to form at
least one heterocyclic ring, the latter ring(s) optionally being
substituted by one or more identical or different radicals defined
as above for R.sup.2 to R.sup.7, n and m independently of one
another take the values 0 to 4, and it being possible, when n
and/or m.gtoreq.2, for two of the radicals R.sup.2 or R.sup.3
optionally to combine to form at least one aromatic ring, a bonding
unit L is provided between two moieties A and B consisting of
aromatic or heteroaromatic rings (A and B being identical or
different), and L is preferably joined to the 2,2'-positions of the
rings A and B, said formula (I) being characterized in that L is
selected from the following group of radicals: 30where: R.sup.8 and
R.sup.9 are identical or different and are a linear or branched
C.sub.1-C.sub.12 alkyl, a C.sub.1-C.sub.12 cycloalkyl, an aryl, an
aralkyl or an alkylaryl, these radicals R.sup.8 and R.sup.9 being:
optionally substituted, and preferably selected from the following
group of radicals: alkylene, phenyl and/or alkyl, methyl and
methylenephenyl radicals being particularly preferred, R.sup.8 and
R.sup.9 can optionally combine to form a substituted or
unsubstituted hydrocarbon ring which may or may not be fused with
at least one aromatic and/or aliphatic ring optionally containing
at least one heteroatom, this ring preferably being aliphatic and
having from 4 to 7 ring members, and x=1 to 3.
2. Compound, particularly photochromic compound, according to claim
1, of the following general formula (I'), in which A and B are
phenyl groups, A=Ph.sub.1, B=Ph.sub.2: 31in which R.sup.2 to
R.sup.7, n and m are as defined in claim 1.
3. Compounds according to claim 1, characterized in that the groups
R.sup.2 to R.sup.7 of formulae (I) and (I') according to the
invention comprise and/or form at least one reactive polymerizing
and/or crosslinking group preferably selected from the following
list: alkenyl, advantageously vinyl, methacryloyl, acryloyl,
acryloxyalkyl, methacryloxyalkyl or epoxy.
4. Compound according to claim 1 or 2, characterized in that, in
formulae (I) and (I'): R.sup.2 and R.sup.3 are hydrogen or --OMe,
and at least two radicals R.sup.4 and R.sup.5 or R.sup.6 and
R.sup.7 form a ring selected from the following group: 32where
R.sup.12 to R.sup.15 are defined as for R.sup.2 to R.sup.7 in claim
1, q, r and s=0 to 4 and t.dbd.0 to 2, and X=O, S or N, and even
more preferably from the following subgroup: 33
5. Compound according to claim 1 which consists of one of the
following products: 34
6. (Co)polymer and/or crosslinked product obtained by the
polymerization and/or crosslinking of at least one monomer formed
by at least one photochromic compound according to claim 3.
7. Copolymer, characterized in that it is grafted with at least one
of the photochemical compounds according to claim 1.
8. Photochromic composition, characterized in that it comprises: at
least one compound according to claim 1 and/or at least one
(co)polymer according to claim 6 or 7, and optionally at least
other photochromic compounds and/or at least one colorant and/or at
least one stabilizer.
9. (Co)polymeric matrix, characterized in that it comprises: at
least one compound according to claim 1, and/or at least one
(co)polymer according to claim 6 or 7, and/or at least one
composition according to claim 8.
10. Matrix according to claim 9, characterized in that the
(co)polymer is selected from the following list: polyalkyl,
polycycloalkyl, polyaryl or polyarylalkyl mono-, di-, tri- or
tetraacrylate or -methacrylate which is optionally halogenated or
contains at least one ether and/or ester and/or carbonate and/or
carbamate and/or thiocarbamate and/or urea and/or amide group,
polystyrene, polycarbonate (e.g. polybisphenol-A carbonate,
polyallyl diethylene glycol carbonate), polyepoxy, polyurethane,
polythiourethane, polysiloxane, polyacrylonitrile, polyamide,
aliphatic or aromatic polyester, polyvinyl, cellulose acetate,
cellulose triacetate, cellulose acetate-propionate or
polyvinylbutyral, copolymers of two or more types of monomers or
mixtures of polymers mentioned above, preferably
polycarbonate/polyurethane, poly(meth)acrylate/polyurethane,
polystyrene/poly(meth)acrylate or polystyrene/polyacrylonitrile,
advantageously a mixture of polyester and polycarbonate or
poly(meth)acrylate.
11. Ophthalmic article, preferably ophthalmic glasses or
sunglasses, comprising: at least one compound according to claim 1,
and/or at least one (co)polymer according to claim 6 or 7, and/or
at least one composition according to claim 8, and/or at least one
matrix according to claim 9 or 10.
12. Ophthalmic article according to claim 11, characterized in that
it consists of a lens.
13. Glazing and/or optical device comprising: at least one compound
according to claim 1, and/or at least one (co)polymer according to
claim 6 or 7, and/or at least one composition according to claim 8,
and/or at least one matrix according to claim 9 or 10.
Description
TECHNICAL FIELD
[0001] The present invention relates to novel compounds of the
spiropyran type which have photochromic properties in particular.
It further relates to the photochromic compositions and ophthalmic
articles (e.g. lenses) containing these spiropyrans.
PRIOR ART
[0002] Photochromic compounds are capable of changing color under
the influence of polychromatic or monochromatic light (e.g. UV) and
of reverting to their initial color when the light irradiation
ceases, or under the influence of a different polychromatic or
monochromatic light from the first, or under the influence of
temperature and/or a different polychromatic or monochromatic light
from the first.
[0003] These photochromic compounds have applications in a variety
of fields, for example for the manufacture of ophthalmic lenses,
contact lenses, sunglasses, filters, lenses for moving or still
cameras or for other optical and observation devices, glazing,
decorative objects or display elements, or alternatively for the
storage of information by optical recording (coding).
[0004] In the field of ophthalmic optics and particularly glasses,
a photochromic lens comprising one or more photochromic compounds
must have, over a wide temperature range (-20.degree. C. to
+50.degree. C.), a high transmission in the dark or in the absence
of sunlight, a low transmission (high colorability) under solar
irradiation, fast coloration and decolorization kinetics, art
appreciable durability with an optimal efficacy, and a pleasant
tint acceptable to the consumer (preferably gray or brown).
[0005] These lens characteristics are in fact determined by the
active photochromic compounds, which must also be perfectly
compatible with the organic or inorganic substrate of which the
lens is made.
[0006] It should furthermore be noted that, to obtain a gray or
brown tint, it may be necessary to use at least two photochromic
compounds of different colors, i.e. with different maximum
absorption wavelengths in the visible (.lambda..sub.max). This
association also makes other demands on the photochromic compounds.
In particular, the coloration and decolorization kinetics of the
two types of active photochromic compounds in association must be
substantially identical. The same applies to their stability over
time and also to their compatibility with a plastic or inorganic
substrate.
[0007] The benzopyrans and naphthopyrans forming the subject of the
invention according to patent U.S. Pat. No. 3,567,605 may be
mentioned among the numerous photochromic compounds described in
the prior art. When subjected to temperatures of the order of -30
or -40.degree. C., these compounds change from a colorless state to
a yellow-orange or even red tint under high energy activating
irradiation of the UV type. These compounds revert to the colorless
state when the temperature is raised (.gtoreq.0.degree. C.) and/or
when they are irradiated in the visible. The thermal and kinetic
conditions of the photochromism peculiar to these compounds seem a
priori to be rather incompatible with common ophthalmic
applications.
[0008] These compounds also have relatively low .lambda..sub.max
values in the visible.
[0009] In the case of photochromic compounds of the pyran type,
high energy radiation (UV) allows the opening of the pyran ring and
hence the conjugation of double bonds. This ring opening causes the
appearance of an absorbance in the visible whose .lambda..sub.max,
colorability Ao and .lambda..sub.max peak height and area are
characteristic.
[0010] Patent application EP 0 562 915 discloses novel heterocyclic
chromenes which are useful as photochromic compounds in the field
of ophthalmic optics. These compounds are benzopyrans or chromenes
substituted by two phenyls, which themselves are optionally
substituted. These photochromic compounds are presented as having a
colorability in the red region (.lambda..sub.max=438-510 nm) and as
being usable with photochromic compounds whose .lambda..sub.max is
situated in the blue (.apprxeq.600 nm). It has been found, however,
that these known compounds are still capable of improvement as
regards their colorability and their photochemical stability.
[0011] More recently, U.S. Pat. No. 5,238,281 has disclosed novel
photochromic compounds of the naphthopyran type substituted in the
5-, 8- and 9-positions of the naphthyl moiety. According to the
assignee, these substitutions, and more particularly the one in the
8-position of a naphthopyran which is itself substituted in the
3-position by two phenyl groups, effects an increase in the
photochromic sensitivity, said increase supposedly being related to
a bathochromic modification of the activating UV spectrum. This
specific substitution of the naphthyl is also said to be the cause
of a bathochromic change in the visible absorption spectrum of the
activated compound (exposed to UV). The two phenyl substituents on
the pyran ring are structurally independent. The .lambda..sub.max
values in the visible of the photochromic compounds according to
this U.S. patent range from 432 nm to 543 nm.
[0012] Despite all these improvements, these naphthopyrans have the
disadvantage of possessing an insufficient colorability and a
.lambda..sub.max (visible) which is rather incompatible with the
most commonly available complementary photochromic compounds for
obtaining satisfactory tints and colorabilities.
[0013] Furthermore, patent applications WO 95/00 504 and WO-A-95/05
382 and U.S. Pat. No. 5,395,567 describe diphenylnaphthopyrans or
diphenylheterobenzopyrans in which the two phenyl radicals, bonded
to the 2-position of the pyran ring, are bridged by a direct
.sigma. bond or the following groups: 1
[0014] In WO 95/00 504 the bridging is proposed in order to reduce
the rate of diffusion of these products in a polymeric matrix.
[0015] The products in which the bridging is formed by a direct
bond are photochemically unstable. Those with the following
bridging:
--O--
[0016] have a low colorability.
[0017] In this state of the art, one of the essential objects of
the present invention is to provide novel compounds, particularly
photochromic compounds, which belong to the spiropyran family and
do not exhibit the disadvantages of the known photochromic
compounds of the same type. In particular, the invention relates to
spiropyrans possessing:
[0018] a high colorability,
[0019] a high sensitivity to the activating irradiation which
causes the opening of the pyran ring (.lambda..sub.max e.g. in the
UV with large peak height and area),
[0020] an absence of coloration or a very weak coloration in the
non-activated (non-exposed) state,
[0021] an intense coloration after activation: large peak height
and area at .lambda..sub.max in the visible,
[0022] .lambda..sub.max in the visible which, in association with
at least one other photochromic compound of complementary
.lambda..sub.max in the visible, permits a substantial coverage of
the visible spectrum,
[0023] high coloration/decolorization rates,
[0024] suitability for photochromism over a wide and extensive
temperature range (-20.degree. C. to +50.degree. C.),
[0025] long durability (of the optimal efficacy),
[0026] it also being necessary for these spiropyrans to be easy to
prepare.
[0027] Another object of the invention relates to the use of the
photochromic compounds in the field of ophthalmic optics and
particularly for their use in and/or on ophthalmic lenses, i.e., in
terms of the invention, lenses for glasses (sunglasses), contact
lenses and lenses for optical devices, inter alia.
[0028] Within the framework of the use of the above-mentioned
photochromic compounds, another object of the invention is to
provide compositions which comprise said photochromic compounds and
are intended for example for use in the coating of ophthalmic
lenses or as constituent chromogenic agents of said lenses.
[0029] Another object of the invention is to provide the
photochromic compound in the form of polymers and/or crosslinking
agents.
[0030] Another object of the invention is to provide an organic
polymeric or copolymeric matrix and/or an inorganic matrix
containing the above-mentioned photochromic compounds in polymeric
or non-polymeric form.
[0031] Another object of the invention relates to the ophthalmic
articles, for example of the lens type (e.g. lenses for
sunglasses), glazing, glazing elements, optical components,
sensors, and devices for coding, storing or displaying information
which contain the above-mentioned photochromic compounds in
polymeric or non-polymeric form, and/or the compositions comprising
them, and/or the organic polymeric matrices or the inorganic
matrices including these compounds and/or compositions.
BRIEF DISCLOSURE OF THE INVENTION
[0032] To achieve these and other objects, it is to the Applicant's
credit to have demonstrated, after numerous studies and
experiments, that, totally surprisingly and unexpectedly, it is
necessary to select, from spiropyrans substituted on C.sub.2 by two
aromatic or heteroaromatic radicals chemically bonded to one
another, certain specific compounds characterized by the nature of
this chemical bond.
DETAILED DESCRIPTION OF THE INVENTION
[0033] Thus the present invention relates to a compound,
particularly a photochromic compound, of the following general
formula (I): 2
[0034] in which:
[0035] R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are
identical or different and are:
[0036] hydrogen,
[0037] an alkyl, cycloalkyl, alkenyl, alkynyl, aryl or heteroaryl
group (preferably phenyl or naphthyl mono-, di- or tri-substituted
by donor or acceptor groups) or an aryloxy or aralkyl group, said
group optionally being halogenated,
[0038] a halogen, preferably F, Br or Cl,
[0039] OR, SR, --OCOR or --COOR, where R.dbd.H, alkyl and/or
cycloalkyl and/or aryl,
[0040] a (poly)ether, a (poly)amide, a (poly)carbonate, a
(poly)carbamate, a (poly)urea or a (poly)ester,
[0041] an amino radical which--once bonded in (I)--produces a
primary, secondary or tertiary amine, said amine being
monosubstituted or disubstituted by alkyl, aryl or aralkyl,
depending on its type,
[0042] or a cyclic amino radical optionally containing one or more
heteroatoms,
[0043] or an electron-attracting group preferably selected from the
group comprising CF.sub.3, CN, NO.sub.2 and SCN,
[0044] at least two of the radicals R.sup.4, R.sup.5, R.sup.6 and
R.sup.7, preferably carried by two vicinal carbons, can optionally
form at least one aromatic or aliphatic ring advantageously having
from 4 to 7 ring members and even more advantageously having five
or six ring members, said ring(s) optionally comprising at least
one heteroatom so as to form at least one heterocyclic ring, the
latter ring(s) optionally being substituted by one or more
identical or different radicals defined as above for R.sup.2 to
R.sup.7,
[0045] n and m independently of one another take the values 0 to 4,
and it being possible, when n and/or m.gtoreq.2, for two of the
radicals R.sup.2 or R.sup.3 optionally to combine to form at least
one aromatic ring,
[0046] a bonding unit L is provided between two moieties A and B
consisting of aromatic or heteroaromatic rings (A and B being
identical or different), and
[0047] L is preferably joined to the 2,2'-positions of the rings A
and B, said formula (I) being characterized in that L is selected
from the following group of radicals: 3
[0048] where:
[0049] R.sup.8 and R.sup.9 are identical or different and are a
linear or branched C.sub.1-C.sub.12 alkyl, a C.sub.1-C.sub.12
cycloalkyl, an aryl, an aralkyl or an alkylaryl, these radicals
R.sup.8 and R.sup.9 being:
[0050] optionally substituted,
[0051] and preferably selected from the following group of
radicals: alkylene, phenyl and/or alkyl, methyl and methylenephenyl
radicals being particularly preferred,
[0052] R.sup.8 and R.sup.9 can optionally combine to form a
substituted or unsubstituted hydrocarbon ring which may or may not
be fused with at least one aromatic and/or aliphatic ring
optionally containing at least one heteroatom, this ring preferably
being aliphatic and having from 4 to 7 ring members, and
[0053] x=1 to 3.
[0054] Contrary to all expectations, joining the two
(hetero)aromatic rings A and B by an appropriate chemical bond to
the carbon in the C.sub.2-position of the pyran ring did not have
negative repercussions on the photochromicity properties of the
compound. On the contrary, it was possible to identify a
substantial improvement in all the photochromic characteristics of
the compounds, especially the colorability and the .lambda..sub.max
in the visible (widening of the .lambda..sub.max range).
[0055] According to a preferred modality of the invention, the two
aromatic rings A and/or B are phenyls joined to one another by the
bonding unit L, which is connected to their respective carbons in
the 2- and 2'-positions. This corresponds to the following general
formula (I'): 4
[0056] in which R.sup.2 to R.sup.7, n and m are as defined
above.
[0057] This novel family of spiropyrans is characterized by the
presence of two rings, respectively pyran and hydrocarbon rings,
joined by the spiro carbon. The choice of specific bonding units L
for these spiropyrans affords very good compromises as regards the
combination of photochromic properties and photochemical stability.
In particular, these bridged spiropyrans have a better colorability
and their photocoloration band experiences a bathochromic shift
relative to the analogous known compounds.
[0058] Moreover, the products according to the invention have
photocoloration and decolorization kinetics adapted to the intended
applications.
[0059] Among the substituents which can be considered for the
compounds of formulae (I) and (I') according to the invention, it
is appropriate to consider groups R.sup.2 to R.sup.7 comprising
and/or forming at least one reactive polymerizing and/or
crosslinking group preferably selected from the following list:
alkenyl, advantageously vinyl, methacryloyl, acryloyl,
acryloxyalkyl, methacryloxyalkyl or epoxy.
[0060] Thus the photochromic compounds according to the invention
can be thought of as monomers of identical or different type which
are capable of reacting with one another or with other comonomers
to form homopolymers and/or copolymers carrying a photochromic
functional group and possessing mechanical properties of
macromolecules. It follows that one of the subjects of the present
invention is formed by these homopolymers or copolymers comprising
(co)monomers, and/or by crosslinked products at least partially
consisting of photochromic compounds (I), (I') according to the
invention.
[0061] Similarly the above-mentioned compounds (I), (I') can be
thought of as crosslinking agents provided with reactive groups
capable of creating bridges between polymer chains of photochromic
or non-photochromic type. The crosslinked products which can be
obtained in this way also constitute a further subject of the
present invention.
[0062] In the structural variant referred to above, according to
which at least two of the radicals R.sup.4 to R.sup.7 form a cyclic
structure, preference is readily given (but without implying a
limitation) to the cyclization of R.sup.4-R.sup.5 to give, in
combination with a grouping shared with the benzyl of the
benzopyranyl unit, one of the following rings: phenyl, pyridyl,
thienyl, furyl, piperidinyl or furfuryl.
[0063] The more particularly preferred ring R.sup.4-R.sup.5 is:
[0064] either a phenyl, the compound obtained thus being a
naphthospiropyran,
[0065] or a heterocycle, advantageously of the type containing
oxygen as the heteroatom, preference being given to tetrahydrofuran
rings optionally fused with a phenyl ring.
[0066] In the latter case, the preferred compound obtained is a
heterobenzopyran.
[0067] Specific examples which may be mentioned of some of the
interesting structures of the compounds of formulae (I) and (I'),
without implying a limitation, are those in which:
[0068] R.sup.2 and R.sup.3 are hydrogen or --OMe,
[0069] and at least two radicals R.sup.4 and R.sup.5 or R.sup.6 and
R.sup.7 form a ring selected from the following group: 5
[0070] where R.sup.12 to R.sup.15 are defined as above for R.sup.2
to R.sup.7, q, r and s=0 to 4 and t=0 to 2,
[0071] and X.dbd.O,S or N, and even more preferably from the
following subgroup: 6
[0072] In general terms, the following designations according to
the invention apply to the foregoing formulae:
[0073] "alkyl" is preferably an optionally unsaturated, linear or
branched hydrocarbon group having from 1 to 10 carbon atoms
(alkenyl, alkynyl),
[0074] "cycloalkyl" is a monocyclic or polycyclic hydrocarbon group
preferably having from 3 to 10 carbon atoms,
[0075] "alkoxy" is a group of the --O- alkyl type preferably having
from 1 to 10 carbon atoms,
[0076] "aryl" is an aromatic hydrocarbon group comprising at least
5 carbon atoms,
[0077] "heteroaryl" is an aromatic hydrocarbon group comprising at
least 5 atoms, at least one of which is a heteroatom,
[0078] "aralkyl" is a group comprising at least one alkyl and at
least one aryl, as defined above,
[0079] "heteroatom" is an atom other than C and H and preferably
belonging to the following group: N, O, S, P, F, Cl, Br.
[0080] As is apparent from the above, the photochromic compounds
which are more readily used within the framework of the invention
are therefore naphthospiropyrans or heterobenzopyrans:
[0081] optionally substituted in the C.sub.8-position of the
naphthopyran ring by an alkoxy, preferably a methoxy,
[0082] and/or optionally carrying an alkoxy group, preferably a
methoxy group, on at least one of the phenyls of the spiro
carbon.
[0083] The following may be mentioned among the most advantageous
spiropyrans: 7
[0084] It is to the Applicant's credit to have discovered these
compounds, because they have truly advantageous photochromic
properties, More precisely, they possess a high colorability,
particularly in the red region. They are therefore suitable for
combination--in total compatibility and complementarity--with
photochromnic compounds absorbing in the blue, to give a wide
coverage of the visible absorption spectrum and hence tints of
brown or dark gray coloration.
[0085] Both their sensitivity and the height and area of their
.lambda..sub.max peaks in the visible attain values which are more
than respectable.
[0086] These compounds are furthermore perfectly stable and
compatible with substrate matrices made of organic polymer or
inorganic material, either in the form of an inclusion in the
matrix or in the form or a coating.
[0087] In solution or in a polymeric matrix, the compounds
according to the invention are colorless or slightly colored in the
initial state (i.e. when not exposed to the activating radiation
cause the opening of the pyran ring) and rapidly develop an intense
coloration under UV light (365 nm) or under a solar type of light
source. Finally, they rapidly revert to their initial color when
the irradiation ceases.
[0088] The compounds of the invention can be obtained by condensing
an aromatic alcohol with a propargyl alcohol. The propargyl alcohol
is itself obtained by reacting an acetylide with a ketone, followed
by hydrolysis. This synthetic route for the preparation of pyran
rings is well known to those skilled in the art and is described
for example in patent U.S. Pat. No. 5,238,981. The scheme for
synthesizing the compounds according to the invention is shown
below. 8
[0089] The propargyl alcohol is synthesized using e.g. either
lithium acetylide (preferably in the form of a diamine complex) or
sodium acetylide (suspended in paraffin oil) in an appropriate
solvent such as tetrahydrofuran, dioxane, toluene, dimethyl
sulfoxide, dimethylformamide or an ether. The reaction with the
ketone takes place at a temperature between -78.degree. C. and
+150.degree. C. The progress of the reaction is monitored
chromatographically on a silica or alumina plate.
[0090] The condensation reaction of the propargyl alcohol with the
aromatic alcohol is carried out in a solvent such as
tetrahydrofuran, dioxane, toluene, benzene or ethanol, in the
presence of an acid catalyst such as paratoluenesulfonic acid,
sulfuric acid, chloroacetic acid or acidic alumina. The
stoichiometry of the reactants, the reaction temperature and the
reaction time depend on the reactivity of the propargyl alcohol and
the aromatic alcohol. These conditions are optimized to give a good
yield. Typically the reaction time can vary from 1 hour to a few
days and the temperature from 0.degree. C. to 100.degree. C.
Another synthetic route, also applicable to some compounds of the
invention, is described in patent application EP 0 562 915.
[0091] As far as the applications the compounds according to the
present invention are concerned, it should be noted that they can
be used as photochromic substances in solution or on and/or in a
polymeric or inorganic matrix.
[0092] A photochromic solution can be obtained by solubilizing the
compound in an organic solvent such as toluene, dichloromethane,
tetrahydrofuran or ethanol. The solutions obtained are generally
colorless and transparent. When exposed to sunlight, they develop a
strong coloration and revert to the colorless state when they are
placed in a zone less exposed to the solar radiation or, in other
words, when they are no longer subjected to UV. In general, very
little product (of the order of 0.01 to 5%) suffices to give an
intense coloration.
[0093] The most common applications are those in which the
photochromic compound is uniformly dispersed in or on the surface
of a polymer, copolymer or mixture of polymers. A very wide variety
of procedures can be considered. An example which may be mentioned
among the procedures known to those skilled in the art is diffusion
into the (co)polymer from a suspension or solution of the
photochromic compound in a silicone oil, in an aliphatic or
aromatic hydrocarbon, in a glycol or in another polymeric matrix.
The diffusion is commonly effected at a temperature of 50 to
200.degree. C. for a period of 15 minutes to a few hours, depending
on the nature of the polymeric matrix.
[0094] Another practical technique consists in mixing the
photochromic compound with a formulation of polymerizable
substances, depositing this mixture on a surface or in a mold and
then performing the polymerization.
[0095] Other practical techniques within the scope of those skilled
in the art are described in the article by CRANO et al. entitled
"Spiroxazines and their use in photochromic lenses", published in
"Applied Photochromic Polymer Systems" by Blackie and Son
Ltd--1992.
[0096] In one variant of the invention, it is also possible to
consider grafting the photochromic compounds onto (co)polymers.
Thus another subject of the invention is formed by the (co)polymers
onto which at least one of the photochromic compounds described
above has been grafted.
[0097] The following products may be mentioned as examples of
preferred polymeric materials for optical applications of the
photochromic compounds according to the invention:
[0098] polyalkyl, polycycloalkyl, polyaryl or polyarylalkyl mono-,
di-, tri- or tetra-acrylate or -methacrylate which is optionally
halogenated or contains at least one ether and/or ester and/or
carbonate and/or carbamate and/or thiocarbamate and/or urea and/or
amide group,
[0099] polystyrene, polycarbonate (e.g. polybisphenol-A carbonate,
polyallyl diethylene glycol carbonate), polyepoxy, polyurethane,
polythiourethane, polysiloxane, polyacrylonitrile, polyamide,
aliphatic or aromatic polyester, polyvinyl, cellulose acetate,
cellulose triacetate, cellulose acetate-propionate or
polyvinylbutyral,
[0100] copolymers of two or more types of monomers or mixtures of
polymers mentioned above, preferably polycarbonate/polyurethane,
poly(meth)acrylate/polyurethane, polystyrene/poly(meth)acrylate or
polystyrene/polyacrylonitrile, advantageously a mixture of
polyester and polycarbonate or poly(meth)acrylate.
[0101] The amount of photochromic compound used depends on the
desired degree of darkening. In general, the amount used is between
0.01 and 20% by weight, based on the total weight of the polymeric
matrix.
[0102] The photochromic compounds according to the invention can be
used by themselves or in a mixture with other products to form a
composition which can be in the solid or liquid form, for example
in solution or in dispersion, as already mentioned above. These
compositions, which constitute a further subject of the invention,
can therefore comprise the compounds (I), (I') of the invention and
other complementary photochromic compounds, making it possible to
obtain the dark gray or brown colorations which the public desires
in applications such as sunglasses. These complementary
photochromic compounds have a .lambda..sub.max and an absorption
surface in the visible which are such that, after association with
the spiropyrans of the invention, an absorption spectrum is
obtained which covers the whole of the visible and imparts the
desired tint to the mixture of activated photochromic
compounds.
[0103] The photochromic compound or compounds which can be
associated with the compounds of the invention are for example the
ones known to those skilled in the art and described in the
literature, namely spirooxazines (J. C. CRANO et al.--"Applied
Photochromic Polymer Systems"--published by Blackie & Son
Ltd.--1992, chapter 2), chromenes (U.S. Pat. No. 3,567,605, EP 0
562 915), spiropyrans or naphthospiropyrans (U.S. Pat. No.
5,238,981).
[0104] These compositions according to the invention can also
contain:
[0105] non-photochromic colorants for adjusting the tint,
[0106] and/or one or more stabilizers, for example an
antioxidant,
[0107] and/or one or more UV inhibitors,
[0108] and/or one or more free radical inhibitors,
[0109] and/or one or more deactivators of photochemical excited
states.
[0110] The durability of said compositions can be improved by these
additives.
[0111] Possibility of Industrial Application
[0112] According to another of its features relating to the
application of the photochromic compounds (I) and (I'), the present
invention further relates to the ophthalmic articles, such as the
ophthalmic glasses or sunglasses, which comprise at least one of
said compounds defined above, and/or at least one (co)polymer at
least partially formed of repeat units of the type (I) or (I'),
and/or at least one composition comprising the compounds (I) and
(I') according to the invention, as defined above, and/or at least
one matrix, as defined above, made of an organic polymeric
material, an inorganic material or an inorganic/organic hybrid
material.
[0113] In practice, the articles to which the present invention
relates more particularly are photochromic ophthalmic lenses,
glazing [windows for buildings and locomotive devices (motor
vehicle)], optical devices such as decorative articles, articles
for solar protection, etc.
[0114] The present invention will be understood more clearly with
the aid of the following Examples of the synthesis and photochromic
validation of the compounds (I) and (I') to which it relates. These
Examples also reveal all the advantages and practical variants of
the present invention.
EXAMPLES
[0115] Synthesis and Properties of Photochromic Compounds (A) to
(J) According to the Invention (Examples 1 to 10)
[0116] The results and formulae are collated in Table 1 below.
1TABLE 1 PHOTOCHROMIC .lambda..sub.max COMPOUND (nm) IOD Stability
(IOD) A (Ex. 1) 9 444 0.93 0.93 B (Ex. 2) 10 485 1.02 0.63 C (Ex.
3) 11 444 1.20 1.10 D (Ex. 4) 12 480 1.10 0.90 E (Ex. 5) 13 480
1.10 0.90 F (Ex. 6) 14 486 0.61 0.60 G (Ex. 7) 15 458 1.13 1.11 H
(Ex. 8) 16 -- -- -- I (Ex. 9) 17 480 1.37 1.35 J (Ex. 10) 18 442
0.26 -- Kc 19 450 1.00 0.00 Mc 20 428 1.1 -- Nc 21 520 <0.2 --
LEGEND: *.lambda..sub.max measured at 0.1% in tetrahydrofuran,
exposed to a 60,000 Lux xenon lamp, at a temperature of
20-25.degree. C. and with 3 mm thick matrix films, *IOD = induced
optical density at saturation, *Stability = Photochemical stability
assessed by measurement of the IOD at saturation after 4 hours of
photochemical ageing.
Example 1
[0117] Synthesis of the Compound A
[0118] LiCCH.NH.sub.2C.sub.2H.sub.2NH.sub.2 (9 g) are added in
small portions, over a period of 3 hours, to a solution of
10,10-dimethylanthrone (7.5 g) in 40 ml of tetrahydrofuran, stirred
at -10.degree. C.
[0119] The mixture is then stirred at 0.degree. C. for 2 hours. It
is subsequently poured onto crushed ice. The propargyl alcohol
obtained is extracted with toluene (3.times.400 ml). This gives a
light brown solid after evaporation of the organic phase. The
structure of the compound is confirmed by NMR spectroscopy. Yield:
8.3 g.
[0120] The product of the previous step (5.2 g) and 2-naphthol
(3.32 g) are solubilized in 50 ml of tetrahydrofuran. A catalytic
amount of p-toluenesulfonic acid is added and the mixture is kept
at room temperature and under a nitrogen atmosphere for 16 h. The
solution is then poured into 100 ml of water and 100 ml of
diisopropyl ether.
[0121] The organic phase is recovered, washed three times in 30 ml
of aqueous sodium hydroxide solution (1 N) and then reduced to
dryness. The product obtained (4.45 g) is recrystallized from a
heptane/diisopropyl ether solvent mixture. Yield: 2.7 g. Its
structure is confirmed by NMR spectroscopy.
Example 2
[0122] Synthesis of the Compound B
[0123] 7 g of the propargyl alcohol of Example 1, 8.8 g of
2,6-dihydroxynaphthalene and a catalytic amount of
paratoluenesulfonic acid are solubilized in 125 ml of
tetrahydrofuran in a 100 ml reactor and the mixture is kept at room
temperature for 2 hours. It is subsequently poured into 100 ml of
water, after which 100 ml of methylene chloride are added. The
organic phase is recovered and then reduced to dryness.
Chromatography on a silica column with a toluene/dichloromethane
eluent gives the "hydroxylated" intermediate with a yield of 25%.
This is then methylated with dimethyl sulfate in acetone, in the
presence of potassium carbonate. The desired product (B) is
obtained, after purification, in the form of a yellowish powder
with a yield of 75%. Its structure is confirmed by NMR
spectroscopy.
Example 3
[0124] Synthesis of the Compound C
[0125] 10 g of anthrone, 5 g of LiOMe and 16 g of diiodobutane are
mixed with 100 ml of xylene in a 250 ml reactor and the reaction
mixture is refluxed for 16 h. It is then poured into 100 ml of
water and 200 ml of toluene. The organic phase is extracted, washed
with aqueous KOH solution and then reduced to dryness. The solid
obtained is macerated in 100 ml of heptane and then filtered off
and dried to give 9 g of spirocyclopentylanthrone. The propargyl
alcohol of the latter is obtained, as in Example 1, by reaction
with lithium acetylide in tetrahydrofuran at -10.degree. C.
[0126] The compound (C) is then obtained, in a manner analogous to
that described in Example 1, from the propargyl alcohol of
spirocyclopentylanthrone and 2-naphthol. The product (C) is
isolated in the form of a cream-colored powder with a yield of 18%
and its structure is confirmed by NMR spectroscopy.
Example 4
[0127] Synthesis of the Compound D
[0128] The compound (D) is obtained, in a manner analogous to that
described in Example 1, from the propargyl alcohol of
spirocyclopentylanthrone (Example 3) and
2-hydroxy-6-methoxynaphthalene. The product (D) is isolated in the
form of a pinkish powder with a yield of 14% and its structure is
confirmed by NMR spectroscopy.
Example 5
[0129] Synthesis of the Compound E
[0130] The compound (E) is obtained, in a manner analogous to that
described in Example 1, from the propargyl alcohol of
spirocyclopentylanthrone and
2-hydroxy-6-p-methoxyphenylnaphthalene. The product (E) is isolated
in the form of a yellowish powder with a yield of 30% and its
structure is confirmed by NMR spectroscopy.
Example 6
[0131] Synthesis of the Compound F
[0132] This compound is synthesized from 10,10-dibenzylanthrone and
2-naphthol. The procedure is similar to that of Example 1. The
product is isolated in the form of a cream-colored powder and its
structure is confirmed by NMR spectroscopy.
Example 7
[0133] Synthesis of the Compound G
[0134] This compound is synthesized from 5,12-naphthacenequinone
and 2-naphthol. The procedure is similar to that of Example 3
(selective reduction of 5,12-naphthacene-quinone with tin and
hydrochloric acid, followed by reaction with diiodobutane). The
product is isolated in the form of a cream-colored powder and its
structure is confirmed by NMR spectroscopy.
Example 8
[0135] Synthesis of the Compound H
[0136] This compound is synthesized from spirocyclopentylanthrone
and 2-hydroxy-dibenzofuran. The product is isolated in the form of
a cream-colored powder and its structure is confirmed by NMR
spectroscopy.
Example 9
[0137] Synthesis of the Compound I
[0138] This compound is synthesized from spirocyclopentylanthrone
and 3-methyl-1-naphthol. The product is isolated in the form of a
cream-colored powder and its structure is confirmed by NMR
spectroscopy.
Example 10
[0139] Synthesis of the Compound J
[0140] This compound is synthesized from spirocyclopentylanthrone
and 2,7-dihydroxy-naphthalene. The hydroxylated product is then
reacted with methacryloyl chloride in toluene, in the presence of
triethylamine. The product is isolated in the form of a
cream-colored powder and its structure is confirmed by NMR
spectroscopy.
Example 11
[0141] Comparative known Compounds Kc, Lc and Mc
[0142] The compound (Kc) is
spiro(9-fluorene-2'-(2H)-naphtho(2,3-b)pyran), described in patent
application WO 95/00 504.
[0143] The compound (Mc) is 3,3-diphenyl-3H-naphtho(2,1-B)pyran,
described in U.S. Pat. No. 3,567,605.
[0144] The compound (Nc) is also disclosed in said patent
application WO 95/00 504, as well as in the work by R. C. BERTELSON
entitled "Photochromism", Ed. G. H. Brown, J. Wiley and Sons Inc.,
N.Y. (1971), chap. III.
APPLICATION
Example 12
[0145] Incorporation of the Compounds into a Polymethacrylate
[0146] General procedure: 5 mg of each of the compounds given in
Table 2 are solubilized in tetraethoxylated bisphenol-A
dimethylmethacrylate (marketed under the name DIACRYL 121 by AKZO),
which also contains 20 mg of 2,2'-azobis(2-methylbutyronitrile).
The solution is subsequently degassed, rendered inert with argon
and then poured into a glass lens mold of diameter 8 cm and
thickness 2 mm. The mold is then placed in an oven at 70.degree. C.
for 12 hours. A rigid transparent lens is obtained after demolding.
Under solar-type irradiation, the glass rapidly develops an orange
to red coloration (the .lambda..sub.max values are given in Table
2) and becomes colorless again in the dark. The photochromic
characteristics are given in Table 2 below. By way of comparison,
the characteristics of the compounds Mc and Nc of the prior art are
also given in Table 2 below.
2TABLE 2 PHOTOCHROMIC .lambda..sub.max TO % TD 15% TF 5% COMPOUND
(nm) at 560 nm at 560 nm at 560 nm D (Ex. 4) 22 484 91 53 76 G (Ex.
7) 23 462 84 5 32 H (Ex. 8) 24 450, 545 89 76 84 I (Ex. 9) 25 488
87 28 37 J (Ex. 10) 26 447 91 87 89 Mc (Ex. 11) 27 434 87 85 90 Nc
(Ex. 11) 28 520 88 86 88 LEGENDS: .lambda..sub.max measured in D121
at a thickness of 2 mm, exposed to a 60,000 Lux xenon lamp, at
22.degree. C., T0 = initial transmission (non-activated state)
meassured at 560 nm, TD15 = transmission after 15 min of exposure,
TF5 = transmission after 15 min of exposure, followed by 5 min of
fading in the dark.
[0147] These measurements (Tables 1 and 2) demonstrate that the
compounds of the prior art do not possess the combination of
desired photochemical properties. The compound Kc is
photochemically unstable, the compound Mc has a rather low
.lambda..sub.max of the activated form and the compound Nc has a
very low intensity of coloration under UV. The compound J allows
grafting onto a polymer by copolymerization.
* * * * *