Note: Descriptions are shown in the official language in which they were submitted.
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W O 97/00276 PCTAg~6~aO_~?
ACTIVE ENERGY RAY-CUFP~3LE RESIN COMPOSITIONS, A CURED ARTICLE AND AN
OP'rICAL LENS OBTAINED THEREFROM, AND NOVEL (MET~)AC~YLATE COMPOUNDS
THEREFOR.
The present invention relates to active energy ray-curable resin
, 5 compositions which can be cured by an active energy ray such as an
ultraviolet ray or electron beam and, further the present invention relates
to a cured article therefrom having a high refractive index, a Fresnel lens
or lenticular lens wherein a thermoplastic resin plate is combined with a
layer of the cured article, and a tr~ncm;~sion type screen in which a
thermoplastic resin is combined with two-layers of the cured article.
The active energy ray-curable resin compositions are excellent in
workability for forming, in properties of a coating layer, and from an
econo~;cal viewpoint. The active energy ray-curable resin compositions can
provide a cured article having a high refractive index, and an optical lens
wherein a thermoplastic resin is combined with two-layers of the cured
article.
The invention also relates to novel (meth)acrylates usable in some of
these compositions.
A~ active energy ray-curable resin composition which can be cured by
irradiation of an active energy ray such as ultraviolet ray or electron
beam has been widely used in a variety of fields such as printing fields,
coatings fields, and electric fields, etc., because of its excellent
productivity and low pollution from a viewpoint of recent environmental
problems.
In a general way, active energy ray-curable resin compositions have
advantageous properties which are (1) a solvent free and low pollution
type, (2) capability of high speed curability and high productivity of
products, (3) capability of slight shrinkage in volume because of curing by
solid of ~00%, and (~) capability of slight th~rm~l loss and minor adverse
th~rm~l affection to base materials, etc.
As more specific uses of the active energy ray-curable resin
compositions, there may be cited resin for inks, coating for plastics,
coating for films, coating for metals, coating for ~urniture, lining
materials, adhesives, insulating varnishes for electronics, insulating
3S sheet, laminated sheet, printed circuit board, resist ink, and
encapsulating materials for semiconductors.
In addition to these uses, the active energy ray-curable resin
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W O 97/00276 PCTABE96/00062
compositions have been employed as resins for moulding and as a cured
article having a high refractive index, such as coatings for an optical
lens, particularly, a Fresnel lens or a lenticular lens, and a transmission
type screen in which a Fresnel lens is combined with a lenticular lens,
owing to the above-described advantageous properties. A Fresnel lens or a
lenticular lens requires thin thickness, and further a high refractive
index, for example, more than 1.47, preferably more than 1.50.
In addition to a high refractive index in a cured article, the
preparation of a cured article for a Fresnel lens or a lenticular lens
reguires quick curing rate by active energy, and the cured article must
have an excellent scratch resistance and a moderate flexibility for giving
an excellent recovery property in a dent generated by compression.
As resins for moulding having a high refractive index in a cured
article, for example, there are disclosed compounds cont~in;ng sulphur in
JP-A-5255464 and JP-B-94025232, and there are disclosed compounds
containing halogens such as bromine except fluorine in JP-A-5117348, there
are disclosed compounds having bromine in JP-A-4216814, and further there
are disclosed acrylate monomer having peculiar aromatic rings in JP-A-
5065318.
However, the compounds disclosed in these JP's are peculiar, and
articles moulded from these compounds are not sufficient in scratch
resistance and recovery property in a dent generated by compression.
In view of this situation, as a result of intensive investigations,
the present inventor has found active energy ray-curable resin compositions
capable of providing a cured article having a high refractive index, a high
~cratch resistance and an excellent recovery property in a dent generated
by compression.
The present invention will be described hereinafter in more detail.
According to a first aspect of the present invention, there is
provided an active energy ray-curable resin composition based on a
urethane(meth)acrylate comprising the reaction product of:
(~) an organic isocyanate having at least two isocyanate groups,
(b) a polyol having a molecular weight of at least 300 which has at
least two hydroxyl groups in the molecule,
(c) at least one compound selected from the group consisting of
compounds represented by following formulae (1) to (5),
CA 02222213 1997-12-11
W O ~7/00276 PCTfiBE~
(1)
~R~ R3
COO C C) lCOO ~ H2C ~ R~
~b
(2)
COO-E~n3 CR,--H,C IC fo~ oco~Rs
(3)
-- _
COO~C~¢ OCO--lC)--OCO~
OH
(4)
Rl ~COO_El,~ECH3~;~oH
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W O 97/00276 PCTABE~6f~
(5)
~Rl
H2C C r IRa - TH ~2
COO , (C) COO- H C - C CH- -c - CH- C
L_I nl - n2 2 1 2 _1 2 n5
Rb ~ ~ ~
wherein R1 is a hydrogen atom or a methyl group, R2 is independently a
hydrogen or an alkyl group having a carbon number ranging from 1 to 10, R3,
R4, and R5 is independently a hydrogen, an alkyl group having a carbon
number ranging from 1 to 10, and phenyl group or bromine, nl is an integer
ranging from 1 to 7, n2 is an integer ranging from 0 to 20, Ra and Rb are
independently a hydrogen or a methyl group, n3 is independently an integer
ranging from 0 to 10, n4 is 0 or 1, and n5 is an integer ranging from 0 to
5.
As the organic isocyanate having at least two isocyanate groups which
are capable of reacting with a hydroxyl group, there are specifically
exemplified isocyanates such as tolylene diisocyanate, 4,4-diphenylmethane
diisocyanate, xylylene diisocyanate, isophorone diisocyanate,
methylenebis(4-cyclohexylisocyanate), 1,6-hexamethylene diisocyanate,
isocyanurates such as trimer of hexamethylene diisocyanate and trimer of
isophorone diisocyanate. The organic isocyanates may be employed solely or
in combination.
As the polyol having a molecular weight of at least 300 which has at
least two hydroxyl groups in the molecule, there are specifically
exemplified polyether polyols such as polyethylene glycol, polypropylene
glycol, and polytetramethylene glycol, lactone-modified polyester polyols
such as a polycaprolactone polyol and a butyrolactone polyol, and
polycarbonate polyols.
The polyols may be employed solely or in combination.
If the polyol which has a~ least two hydroxyl groups in the molecule
has a molecular weight of less than 300, there is an unpractically decrease
in flexibility of a cured article prepared from the active energy ray-
curable resin composition of the present invention.
-
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W O 97~00276 PCTABE96i'~~'~-
As the compounds represented by the above-described general formula
(1), there are specifically exemplified 2-hydroxyethyl-2-
benzene(meth)acryla~e, 2-hydroxypropyl-~-benzene(meth)acrylate, 2-
hydroxybutyl-2-benzene(meth)acrylate, 2-hydroxybutyl-2-(2,4,6-
tribromobenzene)(meth)acrylate, 2-hydroxybutyl-2-(4-
methylbenzene)(meth)acrylate, a lactone-modified product thereof, and a
reaction product of styrene oxide with a caprolac~one-modified
(meth)acrylate, etc.
As the compounds represented by the above-described general formula
(2), there are specifically exemplified 2-hydroxypropyl-3-
benzoate(meth)acrylate, 2-hydroxybutyl-4-benzoate (meth)acrylate, 2-
hydroxypropyl-3-(2,4,6-tribromobenzoate) (meth)acrylate, 2-hydroxypropyl-3-
(4-phenylbenzoate) (meth)acrylate, a lactone-modified product thereof, and
a reaction product of glycidyl(meth)acrylate with a caprolactone-modified
benzoic acid, etc.
As the compounds represented by the above-described general formula
(3), there are specifically exemplified 3-hydroxy-4-benzoate-
cyclohe~lmethyl(meth)acrylate, a lactone-modified product thereof, and a
reaction product of 3,4-epoxycyclohexyl methyl(meth)acrylate with a
caprolac:tone-modified benzoic acid, etc.
Ac the compounds represented by the above-described general formula
(4), there are specifically exemplified 2-hydroxypropyl-2-
(meth)acryloyloxyethyl phthalate, 2-hydroxyethyl-2-(meth)acryloyloxyethyl
phth~l~te, 2-hydroxybutyl-2-(meth)acryloyloxyethyl phthalate, etc.
As the compounds represented by the above-described general formula
(5), there is specifically exemplified a reaction product of 2,4-diphenyl-
4-methyl-1,2-epoxypentane with (meth)acrylic acid or a caprolactone-
modified (meth)acrylic acid.
The compounds represented by the above-described general formulae (1)
to (5) may be employed solely or in combination.
The compounds represented by general formulae ~1) to (5) can be
prepared by the reaction of acrylic acid, methacrylic acid, or a lactone-
adduct thereof with an epoxy compound having at least one aromatic ring.
The reaction is carried out in a ratio of chemical equivalent of carboxylic
'35 group ranging from 0.8 to 1.2, preferably from 0.9 to 1.1, with respect to
1 chemical equivalent of an epoxy group, and at a temperature range of 60
to 150~C, preferably from 80 to 120~C. Catalysts are preferably employed
in order to accelerate the reaction.
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As examples of the catalysts, there are specifically exemplified
benzylmethylamine, triethylamine, and benzyl-trimethyl~mm~nium chloride,
etc. The catalysts are employed in an amount ranging from 0.1 to 10~ by
weight, and preferably from 0.3 to 5~ by weight.
In the formulae (l) to (3) and (5), the structural unit:
Ra
nl
Rb
is derived from a lactone compound such as epsilon-caprolactone, nl depends
upon the lactone compound to be optionally employed, and n2 is the number
of mole of the lactone compound to be introduced. For example, in the case
when epsilon-caprolactone is employed as the lactone compound, both of Ra
and Rb are a hydrogen, and nl is 5.
~he urethane(meth)acrylate is prepared by reaction of the components
(a), (b), and (c). More specifically, 1 equivalent of hydroxyl group in
the component (b) is first allowed to react with from about 1.1 to 2.2
eguivalent of isocyanate group in the component (a) at ordinary pressure
and a temperature ranging from 60 to 90~C to prepare a urethane prepolymer.
Subsequently, 1 equivalent of isocyanate group in the urethane
prepolymer is allowed to react with from about 1.0 to 1.5, preferably from
1.0 to 1.2 equivalent of hydroxyl group in the component (c) at ordinary
pressure and a temperature ranging from 60 to 90~C.
In the case when isocyanate group in the component (a) is below 1.1
equivalent, or in the case when it exceeds 2.2 equivalents, the desired
urethane prepolymer cannot be prepared, resulting in a decrease of
properties, particularly, recovery property in coating layers.
Furthermore, in the case when equivalent of hydroxyl group in the component
(c) with respect to isocyanate group in the urethane prepolymer is below
1.0, there is an increase in residual isocyanates groups in the
urethane(meth) acrylate, resulting in that it causes problems of irritating
a worker and, contrarily, in the case when it exceeds 1.5, there is an
increase in the residual component (c) in the urethane(meth) acrylate,
resulting in that there is a decrease in the releasing property of a cured
article from a mould, and there is a decrease in scratch resistance and
recovery property in a cured article.
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Catalysts are preferably employed in order to accelerate the
reaction. As examples of the catalysts, there are specifically exemplified
dibutyltin dilaurate, dibutyltin diethylhexoate, dibutyltin disulphide,
dibutyltin dibutoxide, etc. The catalysts are employed in an amount
ranging from 50 to 5000 ppm, and preferably from 250 to 1000 ppm.
Furthermore, there can be mixed a compound represented by general
formula (6) described below,
(6)
~c ~ R ~ CH2
CO(OCHR-cH2)n ~ { ~ } C ~ o--(CH CHR20)n C~
Rl
in order to improve the mechanical strength of a cured article prepared
from the active energy ray-curable resin composition of the present
inventi.on.
As the compound represented by general formula (6), it may be
specifi.cally exemplified a reaction product of modified-bisphenol type
compounds such as an ethylene oxide-adduct of bisphenol A or a propylene
lS oxide-adduct of bisphenol A with acrylic acid or methacrylic acid.
In the formula (6), the mark * represents saturation or unsaturation
in the ring, Rl is independently a hydrogen or a lower alkyl group, R2 is
independently a hydrogen or a methyl group, and n is an integer ranging
from 1 to 10 which depends upon the amount by mole of ethylene oxide or
propylene oxide to be introduced.
The reaction of the modified-bisphenol A type compounds with acrylic
acid or methacrylic acid is carried out in a chemical equivalent ratio
ranging from 0.8 to 1.2, preferably from 0.9 to 1.1 of acrylic acid or
methacrylic acid with respect to 1 chemical equivalent of hydroxyl group in
the modified bisphenol A type compounds, and at a eemperature range of 60
to 150, preferably from 80 to 120~C.
Usual catalysts are preferably employed in order to accelerate the
reaction.
The compound represen~ed by general formula (6) can be employed in an
'30 amount ranging from 5 to 60 parts by weight based on 100 parts by weight of the urethane(meth)acrylate.
In the ac~ive energy ray-curable resin composition of the present
invention, there can be mixed 1 to 10 parts by weight of a photo-
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W O 97/00276 PCT~BE96~ '?
polymerization initiator based on 100 parts by weight of the
urethane(meth)acrylate.
As the photo-polymerization initiator, specific examples are benzoin,
benzoin methylether, benzoin isopropylether, acetoph~none, 2,2-dime~hoxy-2-
phenylacetoph~none, 2,2-diethoxy-2-phenylacetoph~no~e, 1,1-
dichloroacetoph~none, 1-hydroxycyclohexylphenylketone, 2-methyl-1-[4-
(methylthio)phenyl]-2-morpholino-propane-1-on, 2-hydroxydi-2-methyl-1-
phenylpropane-1-on, N,N-dimethylaminoacetoph~none, 2-methylanthraquinone,
2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-
amylanthraquinone, 2-aminoanthraguinone, 2,4-diethylthioxanthone, 2,4-
diisopropyl thioxanthone, acetoph~no~e dimethylketal, methylbenzoph~none,
4,4'-dichlorobenzoph~non~, 4,4'-bisdiethyl~m;noh~n~oph~n~ne, and Michler~s
ketone, etc. Furthermore, there can be optionally employed an accelerator
such as ethylester of N,N-dimethyl~m;nohenzoic acid, triethanolamine, and
triethylamine, etc. The photo-polymerization initiators and accelerators
may be employed solely or in combination.
The photo-polymerization initiator may be employed in an amount
ranging from 1 to 10 parts by weight, preferably from 3 to 6 parts by
weight based on 100 parts by weight of the above-mentioned
urethane(meth)acrylate.
Still further, there can be employed an ethylenically unsaturated
- ~ -r other than the compounds represented by the formulae (1) to (5) in
order to adjust the viscosity of the composition or to improve the
properties in coating layers.
As the ethylenically unsaturated ~nom~rs, examples are styrene,
(meth)acrylonitrile, ethyl(meth~acrylate, butyl(meth)acrylate, 2-
ethtylhexyl(meth)acrylate, isobornyl (meth)acrylate,
cyclohexyl(meth)acrylate, 2-chlorostyrene, phenoxyethyl(meth)acrylate,
(meth)acrylic acid, 2-hydroxyethyl(meth)acrylate, 1,6-hexanediol
di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol
tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and
dipentaerythritol hexa(meth)acrylate, etc. These ethylenically unsaturated
m~n~ -rS may be employed solely or in combination.
The urethane(meth)acrylate to be employed in the present invention
can be prepared by conventional reaction methods.
Specifically, the above-described organic isocyanate having at least
two isocyanate groups is allowed to react with a polyol having a molecular
weight of at least 300 which has at least two hydroxyl groups in the
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molecule, and compounds represented by the general formulae (1) to (5) at a
temperature ranging from 60 to 90~C under ordinary pressure. Catalysts are
preferably employed in order to accelerate the reaction.
As examples of the catalysts, there are specifically exemplified
dibutyltin dilaurate, dibutyltin diethylhexoate, dibutyltin sulphide, and
dibutyltin dibuthoxide, etc.
Tlle catalysts are employed in an amount ranglng from 50 to 5000 ppm,
and preferably from 250 to 1000 ppm. The reaction is terminated when a
fixed concentration of residual isocyanate groups is reached.
According to a second aspect of the present invention, there is
provided a cured article having a refractive index of not less than 1.47 at
25~C moulded from the active energy ray-curable resin composition.
The cured article having a refractive index of not less than 1.47 at
25~C can be moulded from the active energy ray-curable resin composition of
the first aspect of the present invention described hereinabove.
Refractlve index is preferably more than 1 50 at 25~C. Reîractive index
can be adjusted by controlling the combination of essential and optional
components to be employed in the urethane~meth)acrylates.
Additivity rule based on components can be applied in refractive
index o~ the cured article as described below.
Refractive index of a mixture = (the sum of respective refractive
index x respective weight ~ in starting materials)/100.
In the case when refractive index at 25~C is below 1.47, the
thickness in a cured article must be unpractically increased.
The cured article of the present invention has not only a high
refractive index but also a capability of îorming flexible coating layers.
Accordingly, a recovery property in a dent generated by compression is
sufficient even though hands of workers or other parts are in contact with
the surface when being stored and transported.
The cured article can be prepared by irradiating the active energy
ray-curable resin composition of the present invention with ultraviolet ray
or electron beam.
Irradiation by ultraviolet ray is carried out with a mercury lamp or
metal halide lamp, etc. from whicr. curing energy of 100 to 1000 mJ/cm2 is
preferably radiated. On the other hand, irradiation by electron beam is
preferably carried out at the conditions of voltage for pressurization of
150 to 250 ~eV and irradiation ~uantity of 1 to 5 mega-rad. Irradiation is
generally carried out in a resin-made mould.
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According to a third aspect of the present invention, there is
provided a Fresnel lens or lenticular lens wherein a thermoplastic resin
having a Haze value of below 10~ is combined with a layer of the cured
article in the second aspect.
According to a fourth aspect of the presen~ invention, there is
provided a transmission type screen wherein a thermoplastic resin having a
Haze value of below 10~ is combined wi~h two layers of the cured article in
the second aspect.
Optical lens, particularly, a Fresnel lens, a lenticular lens, and a
transmission-type screen combined thereof can be prepared by the
combination of a cured article prepared from the active energy ray-curable
reein composition of the present invention with a thermoplastic resin
having a Haze value of not more than 10% based on JIS K7105.
A Fresnel lens can be prepared by the following steps.
First of all, the active energy ray-curable resin composition of the
present invention is coated inside a mould for a Fresnel lens on which
concentrically circular grooves are formed to prepare a coating layer
having the thickness of 100 to 500 microns. Subsequently, onto the coating
layer, there is stuck a plate having 50 microns to 3 mm prepared from a
thermoplastic resin plate having a Haze value of not more than 10%.
Subsequently, from the thermoplastic resin plate through the coating layer,
irradiation is carried out to cure the coating layer, for example, with a
high pressure mercury lamp from which ultraviolet ray of 400 mJtcm2 is
radiated.
Subsequently, a Fresnel lens having the thickness of 150 microns to
3.5 mm can be prepared by removing the mould for Fresnel lens.
A lenticular lens can be also prepared with a mould for a lenticular
lens similarly to the above descriptions.
Specifically, the active energy ray-curable resin composition of the
present invention is coated inside a mould for a lenticular lens on which
minor semicylindrical projections are formed to prepare a coating layer
having the thickness o~ 100 to 500 microns. Subsequently~ from the
thermoplastic resin plate side, irradiation is carried out to cure the
coating layer, for example, with a high pressure mercury lamp from which
ultraviolet ray of 400 mJ/cm2 is radiated.
A tr~nc~i~sion-type screen combined thereof can be by the following
steps. First of all, a Fresnel lens or a lenticular lens can be prepared
as described hereinabove. Subsequently, thermoplastic resin plate in the
CA 02222213 1997-12-11
W O 97100276 PCT~B~96/COC'~
11 '
Fresnel lens or lenticular lens is stuck on coating layer coated inside a
mould for a lenticular lens or a Fresnel lens. Subsequently, irradiation
is carried out to cure the coating layer. As a result, a transmissioh-type
screen can be prepared by removing the mould for a lenticular lens or a
Fresnel lens.
As the thermoplastic resin having a Haze value of not more than 10
based on JIS K7105, there are speci~ically exemplified a
polymechylmethacrylate, a polystyrene, a polycarbonate, and a copolymer
thereo:E. Of those, a polymethylmethacrylate and a polystyrene are
preferably employed.
~ccording to a fifth aspect of the present invention, there is
provided an active energy ray-curable resin composition cont~;n;ng per 100
parts by weight of the combined weights of (d), (e), and (f):
(d) 15 to 95 ~ by weight of a urethane(meth)acrylate prepared from
an organic polyisocyanate having at least one aromatic ring or
at least one alicyclic ring, and a (meth)acrylate having
hydroxyl group,
~e) 1 to 8 % by weiyht of a (meth)acrylic-based mon( -r having at
least one bromine atom, and optionally
(f) a curable ~nom~r,
~s the organic polyisocyanate having at least one aromatic ring or at
least one alicyclic ring, there are specifically exemplified isocyanates
such as tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, xylylene
diisocyanate, isophorone diisocyanate, methylenebis(4-
cyclohexylisocyanate), isocyanurates such as a trimer of hexamethylene
diisocyanate and a trimer of isophorone diisocyanate. The organic
isocyanal:es may be employed solely or in combination.
The urethane(meth)acrylate which is the component (d) can be prepared
by a reaction of the above-described organic polyisocyanate with a
(meth)acrylate having a hydroxyl group.
As the (meth)acrylate having a hydroxyl group, there are specifically
exemplified 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl~meth)acrylate, 2-
hydroxybutyl(meth)acrylate, 3-hydroxybutyl(meth)acrylate, 4-
hydroxybu~yl(me~h)acrylate, phenoxyhydroxypropyl(meth)acrylate, an ethylene
oxide-modified phthalic(meth)acrylate, a propylene oxide-modified
phthalic~meth)acrylate, a polyethyleneglycol mono(meth)acrylate,
pentaeryt:hritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, and a
lactone-~odified 2-hydroxyethyl (meth)acrylate. The (meth)acrylates having
CA 022222l3 l997-l2-ll
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12
a hydroxyl group may be employed solely or in combination.
In the reaction for the preparation of the urethane (meth~acrylate
which is the component (d), polyols are additionally employed. As the
polyols, there are specifically exemplified a polyethyleneglycol, a
polypropyleneglycol, a polytetramethylene glycol, and a polylactone polyol,
etc.
The polyols may be employed solely or in combination.
The reaction can be carried out by conventional processes.
Specifically, at least one of the polyisocyanates, at least one of the
(meth)acrylates having a hydroxyl group, and optionally at least one of the
polyols, are allowed to react at ordinary pressures and at a temperature
ranging from 60 to 90~C.
In the reaction, there can be preferably employed catalysts such as
dibutyltin dilaurate, dibutyltin diethylhexoate, and dibutyltin sulphide,
etc. The catalysts are employed in an amount ranging from 50 to 5000 ppm,
and preferably from 250 to 1000 ppm. The active energy ray-curable resin
composition of the fifth aspect in the present invention can be prepared by
mixing 15 to 95% by weight, preferably from 30 to 80% by weight of the
urethane(meth~acrylate which is the component (d~ with 1 to 8% by weight,
preferably from 3 to 6~ of a (meth~acrylic-based m~n~m~r having at least
one bromine atom which is the component (e), and a curable ~n- -r which is
the component (f).
In the case when the amount of the urethane(meth)acrylate is below
15~ by weight, the toughness of the cured layer unpreferably decreases and,
contrarily, in the case when it exceeds 90% by weight, there is
unpreferably an increase of the viscosity of the active energy ray-curable
resin composition, resulting in that the composition is not a~lo~iate for
practical uses.
On the other hand, in the case when the amount of the (meth)acrylic-
based mo~m~ having at least one bromine atom is below 1% by weight, therefractive index does not increase and, contrarily, in the case when it
exceeds 8~, not only the scratch resistance and recovery property decrease,
but also the cost of the composition disadvantageously increases.
As the (meth)acrylate monomer having at least one bromine atom, there
is employed at least one compound selected from the group consisting of a
methyl(meth)acrylate-2,4,6-tribromophenol, a brominated di(meth)acrylate of
an ethyleneoxide adduct of bisphenol A, and compounds represented by
general formulae (7) to (9)
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13
(7)
H2C c~Rl Ta CR2~R4
COO ~ C)1COO ~ H2C Rs
~b
Rl ~b ~ R~
(9)
R
H2C - C\ ~ Ra ~ R3
COO ~ ¦ nl ~ RR4
OH
wherein R1 is a hydrogen atom or a methyl group, R2 is independently a
hydrogen or an alkyl group having a carbon number ranging from 1 to 10, R3,
R4, and R5 is independently a hydrogen, an alkyl group having a carbon
number ranging from 1 to 10, and phenyl group or bromine in which at least
one of R3, R4, and Rs is a bromine, nl is an integer ranging from 1 to 7,
n2 is an integer ranging from 0 to 20, Ra and Rb are independently a
'10 hydrogen or a methyl group, and n3 is independently an integer ranging from
0 to 10.
It is to be noted tha~ the compounds represented by the above-
described general formulae (7) to (9) essentially includes a~ least one of
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W O 97/00276 PCTABE9G/C-C'?
14
bromine atom compared to the compounds represented by the above-described
general formulae (1) to (3~ in the first aspect in which bromine atom is
not essential. Compounds (7) to (9) are prepared in the same way as
compounds (1) to (3).
In the active energy ray-curable resin composition of the fifth
aspect of the present invention, a curable monomer which is the component
(f) is optionally employed in order to adjust the viscosity of the
composition and/or the properties of coating layers.
As the curable ~onom~r~ there are specifically exemplified styrene,
(meth)acrylonitrile, ethyl(meth)acrylate, butyl(meth)acrylate, 2-
ethylhexyl(meth)acrylate, isobornyl(meth~acrylate,
cyclohexyl(meth)acrylate, 2-chlorostyrene, phenoxyethyl(meth)acrylate,
acrylic acid, (meth)acrylic acid, 2-hydroxyethyl(meth)acrylate, 1,6-
h~ne~; ol di(meth)acrylate, trimethylolpropane tri(meth)acrylate,
pentaerythritol tri(meth)acrylate, pentaerythritol tetra (meth)acrylate,
and dipentaerythritol hexa(meth)acrylate, etc.
Furthermore, the compound represented by the above-described general
formula (6) is preferably added to the composition in order to improve the
-Ch~n; cal strength of a cured article as well as the active energy ray-
curable resin composition in the first aspect. The compound represented by
the general formula (6) can be employed in an amount ranging from 5 to 60%
by weight based on 100 parts by weight of the components (d), (e), and (f).
Also in the active energy ray-curable resin composition of the fifth
aspect, it may be added from 0.5 to 15 parts by weight, preferably from 3
to 8 parts by weight of the photo-polymerization initiator and accelerator
described in the first aspect, based on 100 parts by weight of the
components (d), (e), and (f).
According to a sixth aspect of the present invention, there is
provided a cured article having a refractive index of not less than 1.~7 at
25~C moulded from the active energy ray-curable resin composition in the
fifth aspect. The cured article can be prepared as well as in the second
aspect.
According to a seventh aspect of the present invention, there is
provided a Fresnel lens or lenticular lens wherein a thermoplastic resin
havins a Haze value of below 10% is combined with a layer of the cured
article as in the sixth aspect.
The Fresnel lens or lenticular lens can be prepared as well as in the
third aspect.
CA 022222l3 l997-l2-ll
W O ~7/00276 PCTABE~C/C~C'~-
According to an eighth aspéct of the present invention, there is
provided a transmission type screen wherein a thermoplastic resin having
Haze vallle o~ below 10~ is combined with two layers of the cured article as
in the sixth aspect.
The transmission type screen can be prepared as well as in the ~ourth
aspect.
According to a ninth aspect of the present invention, there is
provided an active energy ray-curable resin composition cont~; n; ny:
(d~ at least one urethane(meth)acrylate prepared from an organic
polyisocyanate having at least one aromatic ring or at least
one alicyclic ring, and a~ least one (meth)acrylate having one
hydroxyl group, and
(f) an ethylenic unsaturated m~n- ?r ~ except the bisphenol
derivative of formula (6a)
(6a)
C~(OCHR2CH2)n O ~ ~l O (C~2CHR2O)-C ~ 2
wherein R1 is independently a h~dLogen or a lower alkyl group, R2 is
independently a hydrogen or a methyl group, and n is an integer ranging
from 1 to 10.
The component (d) in the ninth aspect is identical to the component
(d) in the fifth aspect, and the component (f) in the ninth aspect is
identical to the component (f) in the fifth aspect.
Furthermore, the compound represented by the above-described general
formula (6), exception being made of the compound represented by formula
(6a), is preferably added to the composition in order to improve the
--hAn;cal strength of a cured article as well as the active energy ray-
curable resin composition as in the first and fifth aspects. The compound
represented by the general formula (6) can be employed in an amount ranging
from 5 to 60% by weight based on 100 parts by weight of the components (d)
and (f).
Also in the active energy ray-curable resin composition of the ninth
aspect, it may be added from 0.5 to lS parts by weight, preferably from 3
to 8 parts by weight of the photo-polymerization initiator and accelerator
described in the first and fifth aspects, based on 100 parts by weight of
CA 022222l3 l997-l2-ll
W O 97/00276 PCT~BE96/0~~-~
16
the components (d) and (f).
According to a tenth aspect of the present invention, there is
provided a cured article having a refractive index of not less than 1.47 a~
25~C moulded from the active energy ray-curable resin composition in the
ninth aspect. The cured article can be prepared as well as in the second
and sixth aspects.
According to an eleventh aspect of the present invention, there is
provided a Fresnel lens or lenticular lens wherein a thermoplastic resin
having a Haze value of below 10~ is combined with a layer of the cured
article in the ninth aspect.
The Fresnel lens or lenticular lens can be prepared as well as in the
third and seventh aspects.
According to a twelfth aspect of the present invention, there is
provided a tr~nc~icsion type screen wherein a th~ plastic resin having
Haze value of below 10~ is combined with two layers of the cured article in
the ninth aspect.
The trAncm;csion type screen can be prepared as well as in the fourth
and eighth aspect.
Furthermore, according to a thirteenth aspect of the invention, there
are provided new (meth)acrylates corresponding to the compounds of formulae
(3) and (5) of the first aspect of the invention. More specifically, 3-
l.ydlo~y-4-benzoate cyclohexylmethyl methacrylate, synthesised in following
Synthesis Example 3 and used to prepare the ureth~n~m~thacrylate UA-8 of
Synthesis Example 8, is a new compound responding to formula (3). Also, 2-
hydroxy-2,4-diphenyl-4-methyl-pentylacrylate synthesised in following
Synthesis Example 4 and used to prepare the urethaneacrylate UA-9 in
Synthesis Example 9, is a new compound responding to formula (5).
Finally, according to a fourteenth aspect of the invention, there are
provided new brominated (meth)acrylates corresponding tO the compounds of
formulae (7), (8) and (9). These compounds are prepared in the same way as
set forth for the compounds of formulae (1) to (3).
The following Examples illustrate the present invention without
limiting it. The percentages are by weight.
Methods or testing:
(l) W curability:
A coating layer having the thickness of 200 microns was coated on a
glass plate. Subsequently, the coating layer was irradiated twice by
CA 022222l3 l997-l2-ll
W O 97/00276 PCr~BE~6/V__f~
17
an ultraviolet ray with a power of 120W/cm and a velocity of 5m/min
with a high pressure mercury lamp to prepare a cured layer.
Subseauently, the cured coating layer was peeled from the glass
plate.
W curability was evaluatea by finger-touch. Evaluation grade is as
r follows.
o: the absence of tackiness
~: the presence of slight tackiness
x: the presence of tackiness
(2) Refractive index:
Refractive index of the cured coating layer was measured with an Abbe
refractometer at 25~C according to JIS K0062.
(3) Elongation at break (%) and
(4) Strength at break (kg/mm2):
Tensile test relating to the cured coating layer was carried out at
the conditions of sample length of 10 cm, marked length for measuring
elongation of 6 cm, tensile speed of 100 mm/minute with a tensile
tester.
(5) Scratch resistance:
The cured coating layer was rubbed extending over 30 mm with a metal
piece in steel having a thickness of 0.2 mm and a width of 10 mm
which is polished by a sAn~rAper. Subsequently, there was visually
observed the presence or absence of scratches.
o: the absence of scratches
~: not more than 5 scratches
x: more than 6 scratches
(6) Recovery property of a dent:
The cured coating layer was pushed at the pressure of 30 kg/cm2 with
a metal rod having the diameter of 5 mm at the point for 5 seconds,
and the time after which a dent disappears was measured.
.~: disappeared immediately
o: disappeared within 30 seconds
~: disappeared within 60 seconds
x: disappeared after more than 60 seconds
Synthesis Example 1
A reaction vessel equipped with an agitator, a th~mom~ter~ a
dropwise ~unnel, and an inlet ~or supplying dried air was placed in an oil
CA 02222213 1997-12-11
W O 97/00276 PCT~BE~6
bath, and charged with 240g (2 mole) of styrene oxide (manufactured by
Daicel Chemical Industries, Ltd.) and 0.5g of triethylamine; the vessel was
then heated to 90~C.
Subsequently, 144g (2 mole) of acrylic acid was gradually added
dropwise from the dropwise funnel, and the reaction was allowed to continue
until the concentration of oxirane oxygen had decreased below 0.5%, to
obtain 2-hydroxyethyl-2-phenylacrylate.
Synthesis Example 2
The same procedures as in Synthesis Example 1 was followed except
that 284g (2 mole) of glycidyl methacrylate were employed in place of
styrene oxide and 244g (2 mole) of benzoic acid in place of acrylic acid,
to obtain 2-hydroxypropyl-3-benzoate methacrylate.
Synthesis Example 3
The same procedures as in Synthesis Example 2 was followed except
that 392g (2 mole) of 3,4-epoxy cyclohexylmethyl methacrylate (Cyclomer
N100 manufactured by 3aicel Chemical Industries, Ltd.) was employed in
place of glycidyl methacrylate, to obtain 3-hydroxy-4-benzoate
cyclohexylmethyl methacrylate.
Synthesis Example 4
A warm water-jacketed reaction vessel equipped with an agitator, a
th~rml -ter, a dropwise funnel, and an inlet for supplying nitrogen gas was
charged with 472g (2.2 mole) of 2,4-diphenyl-4-methyl-1-pente~e; the vessel
was then heated to 50~C.
Subsequently, 167g (2.2 mole) of peracetic acid was added dropwise
over 1 hour and the reaction was allowed to proceed for 4 hours.
After cooling ~o 30~C, washing by water was repeated until the acid
value had decreased below 1 mg KOH/g. Volatile components were removed
from the reaction product with a dryer at a reduced pressure, to obtain
2,4-diphenyl-4-methyl-1,2-epoxypentane.
Subsequently, the same procedures as in Synthesis Example 1 was
followed except that 252g (1 mole) of 2,4-diphenyl-4-methyl-1,2-
epoxypentane was employed in place of styrene oxlde, to obtain 2-hydroxy-
2,4-diphenyl-4-methyl-pentylacrylate.
Synthesis Example 5
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W O 97/00276 PCTABE9G/OO~
19
A reaction vessel equipped with an agitator, a th~rmom~ter~ a
dropwi.se funnel, and an inlet for supplying dried air was placed in an oil
bath, and charged with 444g (2 mole) of isophorone diisocyanate and 0.5g of
dibutyltin dilaurate; the vessel was then heated to 70~C.
Subsequently, 530g (1 mole) of a polycaprolactone diol having a
molecular weight of 530 (Placcel 205 manufactured by Daicel Chemical
Industries, Ltd.) was gradually added from the dropwise funnel. After the
completion of addition, the reaction was allowed to continue until the
concent:ration of residual isocyanate groups attained a theoretical value.
Subsequently, 616g (2 mole) of 2-hydroxyethyl-2-acryloyloxyethyl
ph~h~l~te (Biscoat 2308 manufactured by Osaka Yuki Industries, Ltd.) was
added. After the completion of addition, the reaction was allowed to
continue until the concentration of the residual isocyanate groups attained
a value below 0.1%, to obtain a ureth~ne~crylate (hereinafter, referred to
as UA-5).
Synthesis Example 6
The same procedures as in Synthesis Example 5 was followed except
that 384g (2 mole) of 2-hydroxyethyl-2-phenylacrylate obtained in Synthesis
Example 1 was employed in place of 2-hydroxyethyl-2-acryloyloxyethyl
phthalate, to obtain a ureth~neA~rylate (hereinafter, referred to as UA-6).
Synthesis Example 7
l'he same procedures as in Synthesis Example 5 was followed except
that 528g (2 mole) of 2-hydroxypropyl-3-benzoate methacrylate obtained in
Synthesis Example 2 was employed in place of 2-hydroxyethyl-2-
acryloyloxyethyl phth~l~te, to obtain a ureth~ne~rrylate (hereinafter,
referred to as UA-7).
Synthesis Example 8
The same procedures as in Synthesis Example 5 was followed except
that 636g (2 mole) of 3-hydroxy-4-benzoate cyclohexylmethyl methacrylate
obtained in Synthesis Example 3 was employed in place of 2-hydroxyethyl-2-
acryloyloxyethyl phthalate, to obtain a urethaneacrylate (hereinafter,
referred to as UA-8).
Synthesis Example 9
The same procedures as in Synthesis Example 5 was followed except
CA 022222l3 l997-l2-ll
W O 97/00276 PCT~B~C~ ~'?
that 648g (2 mole) of 2-hydroxy-2,4-diphenyl-4-methyl-pentylacrylate
obtained in Synthesis Example 4 was employed in place of 2-hydroxyethyl-2-
acryloyloxyethyl phthalate, to obtain a urethaneacrylate (hereinafter,
referred to as UA-9~.
Synthesis Example 10
The same proceaures as in Synthesis Example 5 was followed except
that 348g (2 mole) of tolylene diisocyana~e was employed in place of
isophorone diisocyanate, to obtain a urethaneacrylate (hereinafter,
referred to as UA-10).
Synthesis Example 11
The same procedures as in Synthesis Example 5 was followed except
that 336g (2 mole) of hexamethylene diisocyanate was employed in place of
isophorone diisocyanate, to obtain a ureth~n~rylate (hereinafter,
referred to as UA-11).
Synthesis Example 12
The same procedures as in Synthesis Example 5 was followed except
that 524g (2 mole) of methylenebis-4-cyclohexylisocyanate was employed in
place of isophorone diisocyanate, to obtain a urethaneacrylate
(hereinafter, referred to as UA-12).
Synthesis Example 13
The same procedures as in Synthesis Example 5 was followed except
that 508g (2 mole) of 4,4-diphenyl methane diisocyanate was employed in
place of isophorone diisocyanate, to obtain a ureth~ne~crylate
(hereinafter, referred to as UA-13).
Synthesis Example 14
The same procedures as in Synthesis Example 5 was followed except
that 600g (1 mole) of a polyethylene glycol having an average molecular
weight of 600 was employed in place of the polycaprolactone diol, to obtain
a urethaneacrylate (hereinafter, referred to as UA-14).
Synthesis Example 15
The same procedures as in Synthesis Example 5 was ~ollowed except
th~t 500g (1 mole) of a polycarbonate diol having an average molecular
CA 022222l3 l997-l2-ll
W O 97/00276 PCTABE96/00062
21
weight of 500 (CD-205 manufactured by Daicel Chemical Industries, Ltd.) was
employed in place of the polycaprolactone diol, to obtain a
urethaneacrylate (hereinafter, referred to as UA-15).
It is to be noted that the polycarbonate diol (CD-205) has a chemical
formula of HO-(C~2)6-[-OCO(CH2)O-]n-H.
Synthesis Example 16
The same procedures as in Synthesis Example 5 was followed except
that 232g (2 mole) o~ hydroxyethyl acrylate (HEA~ was employed in place of
2-hydroxyethyl-2-acryloyloxyethyl phthalate, to obtain a urerh~n~crylate
(hereinafter, referred to as UA-16).
Synthesis Example 17
The same procedures as in Synthesis Example 5 was followed except
that 688g (2 mole) of an epsilon-caprolactone-modified 2-hydroxyethyl
acrylat:e (PCL FA-2 manufactured by Daicel Chemical Industries, Ltd.) was
lS employed in place of 2-hydroxyethyl-2-acryloyloxyethyl phthalate, to obtain
a urethaneacrylate (hereinafter, referred to as UA-17).
Synthesis Example 18
The same procedures as in Synthesis Example 5 was followed except
that 696g (2 mole) of pentaerythritol triacrylate (PETIA manufactured by
Daicel-UCB, Ltd.) was employed in place of 2-hydroxyethyl-2-
acryloyloxyethyl phthalate, to obtain a urethane acrylate (hereinafter,
re~erred to as UA-18).
Examples 1 to 18 and Comparative Examples 1 to 5
Resin compositions were prepared according to respective mixing ratio
(parts by weight) as shown in Tables 1 and 2, and the properties of coating
layers cured by ultraviolet ray were evaluated. Results are shown in
Tables l and 2.
CA 02222213 1997-12-11
W O 97/00276 PCTABE96/00062
22 ~ o.
~ o .o
O ~ ~ ~!
o o o
r' o o o
o O ~~ ~ o
o CO
o U~ ol
~D O O ~ Ln .
o o~ ~ ~i o
o ~ a~
U~ o o ~ o
~ ~ ~ ~ ~ o ~ ~ ~ ~ ~!
~ ~D i
o Ul o _~
o o _~
o o~ ~ ~ O d~
o In O
.~- o o o
O O~ ~ _I O '~D
o ~ a~
o o . Ul
o ~ o
o~ o
o o . o
o o ~ o
o U~
o o o . o
DO ~ o
Q
O O .
DO ~ O~ ~ O '~
~1~ 0 ~ Ln O
E~ o o ~ --I -
O _~ ~1 ~ 0 ~3i
~ u~ ~n
O O ~ U~
O ~ a~ ~--I o u~
L
O Ul
O O ~ O
o ~ t~ ('~ O 8
o U~
o o ~ o
O _I ~D ~ O
~ _I
o ~n o
o o ~ o
O O _I ~D C'3 0
O In r~-
o o ~ o
~ ~ U-~ ~D O ~ t~ O '5 ~
tL j
~I O L
O O ~ O
~ O O. i~ ~1 O '~
o ~o ~
o o ~o ~ I
O ~ O i~!
_ _ _ _ _ _, ~
>,
m
o ~ ~ ~ ~ u~ ~ I
a ~ ~ m
o m m ~ 2 a
CA 022222l3 l997-l2-ll
W O 97/00276 PCT~RE9C~'~ CC -~
23
Table 2
Comparative Example
1 2 3 4 5
UA-5 100
UA-16 100 100
J UA-17 100
UA-18 100
EOMDA 30
IBOA-B 50 20 50 50 50
~ATBP 15
DC-1173 6 6 6 6 6
property (1) o o c o
(2) 1.45 1.46 1.45 1.45 1.55
(3) 70 60 120 40 75
(4) 1.88 2.13 0.97 3.08 0.88
(5) ~ ~ ~ ~ x
(6) ~ ~ o X x
In the Tables 1 and 2, abbreviations and (numbering) are as follows:
UA-5 to ~A-18: urethane(meth)acrylates prepared in Synthesis Examples 5
to 18
EOMDA: an ethylene oxide-modified bisphenol type diacrylate
(n=1-10) which is EB-lS0 ~-nl-f~ctured by Daicel-UCB, Ltd.
IBOA-B: iso~ornyl acrylate which is IBOA-B manufactured by
Daicel-UCB, Ltd.
BMA: benzylmethacrylate
PEA: phenoxyethyl acrylate
DPEHA: dipentaerythritol h~AA~rylate
MATBP: l-methylacrylate-2,4,6-tribromophenol
DC-1173: 2-hydroxy-2-meth-1-phenylpropane-1-on which is Darocure
1173 manufactured by Ciba-Geigy, AG.
(1): W curability
(2): Refractive index or cured coating layer at 25~C
(3): Elongation at break (~)
(4): Strength at break (kg/mm2)
(5): Scratch resistance
(6): Recovery property of a dent
Synthesis Example 19
A reaction vessel equipped with an agi~ator, a th~rm- ?ter, a
dropwise funnel, and an inlet for supplying dried air was placed in an oil
CA 022222l3 l997-l2-ll
W O 97/00276 PCTABh~G
24
bath, and charged with 348g (2 mole) of 2,4-tolylene diisocyanate and O.5g
of dibutyltin dilaurate, and the vessel was then heated to 70~C.
Subse~uently, 688g (2 mole) of an epsilon-caprolactone-modified 2-
hydroxyethyl acrylate having a molecular weight of 344 (PCL FA-2
manufactured by Daicel Chemical Industries, Ltd.) was added dropwise from
the dropwise funnel.
After adding dropwise, the reaction was allowed to continue until the
concentration of residual isocyanate groups reached a value below 0.1%, to
obtain a urethaneacrylate (hereinafter, referred to as UA-19).
Synthesis Example 20
The same procedures as in Synthesis Example 19 was followed except
that 444g (2 mole) of isophorone diisocyanate was employed in place of 2,4-
tolylene diisocyanate, to obtain a urethaneacrylate (hereinafter, referred
to as UA-20).
Synthesis Example 21
The same procedures as in Synthesis Example 19 was followed except
that 362g (2 mole) of hexamethylene diisocyanate was employed in place of
tolylene diisocyanate, to obtain a ure~h~ne~crylate (hereinafter, referred
to as UA-21).
Examples 19 to 21 and Comparative Examples 6 and 7
Resin compositions were prepared according to respective mixing ratio
(parts by weight) as shown in Table 3. The properties of coating layers
cured by an ultraviolet ray were then evaluated. Results are shown in
Table 3.
-
CA 022222l3 l997-l2-ll
W O ~7l'00276 P ~ ~ G~aC0~?
Table 3
ExampleComparative Example
19 20 21 6 7
UA-19 65 - 45 - -
UA-20 - 65
UA-21 - - - 65 70
MATBP 5 5 5 5
MBPADA - - 20
EA 30 30 30 30 30
IC 184 6 6 6 6 6
(1) 0 o o o o
(2) 1.50 1.49 1.52 1.45 1.46
(3) 120 100 90 130 100
(4) 1.24 1.55 1.83 1.07 1.61
(S) o o o o
(6) ~ ~ ~ x x
In the Table 3, abbreviations and (numbering~ are as ~ollows:
MATBP: 1-methylacrylate-2,4,6-tribromophenol
MBPADA: a modified bisphenol type diacrylate which is one of the
compounds represented by the general formula (6).
EA: ethylacrylate
IC 184: 1-hydroxycyclohexyl phenylketone which is Irugacure 184
manufactured by Ciba-Geigy, AG.
(1): W curability
(2): Refractive index of cured coating layer at 25~C
(3): Elongation at break (~)
(4): Strength at break (kg/mm2)
(5): Scratch resistance
(6): Recovery property of a dent
Examples 22 to 25 and Comparative Examples 8 and 9
Resin compositions were prepared according to respective mixing ratio
(parts by weight) as shown in Table 4. The properties of coating layers
cured by ultraviolet ray were then evaluated. Results are shown in Table
4.
CA 02222213 1997-12-11
W O 97/00276 PCTABEg6~C~
26
Table 4
ExampleComparative Example
22 23 24 25 8 9
UA-l9 100 100 - - - -
UA-20 - - 100 100
UA-21 - - - - 100 100
IBOA-B 20 20 20 20 20 20
MBPADA - 30 - 30 - 30
DC 1173 6 6 6 6 6 6
(1) 0 0 0 0 0 .J
(2) 1.52 1.53 1.50 1.51 1.45 1.46
(3) 90 75 85 80 110 85
(4) 1.66 1.98 1.43 1.76 1.88 2.13
(5) o o o o x
(6) ~ ~ ~ ~ x x
In the Table 4, abbreviations and (numbering) are as follows:
I80A-B: isobornyl acrylate ~nllf~rtured by Daicel-UCB, Ltd.
M8PADA: an ethylene oxide-modified bisphenol type diacrylate which is
EB-150 (n=1-10) -n~lfActured by Daicel-UCB, Ltd.
DC 1173: 2-hydroxy-2-meth-1-phenylpropane-1-on which is Darocure 1173
manufactured by Ciba-Geigy, AG.
(1): W curability
(2): Refractive index of cured coating layer at 25~C
(3): Elongation at break (~)
(4): Strength at break (kg/mm2)
(5): Scratch resistance
(6): Recovery property of a dent
While the invention has been described in detail and with reference
to specific embodiments thereof, it will be apparent to one skilled in the
art that various changes and modifications can be made therein without
departing from the spirit and scope thereof.
