3) U.S.P. 3,205,157. 4) B.P. 893, 063. 5) H. Ito and C. G. Wilson, SPE Regional Tech- nical Conference on Photopolymers (Ellenville,. New York, Nov. 1982), p.
J. Soc. Photogr. Sci. Technol. Japan,
研
究
Studies
on Diazo
Vol. 47, No. 5, 1984
Type
Process.
VIII
Quantitative Analysis of Boron Trifluoride generated by Photodecomposition of Benzene Diazonium Tetrafluoroborate Kieko
HARADA,
Nobuo and
Department
UENO,
Shin
Kazuyuki
SUGITA
SUZUKI
of Image Science and Technology, Faculty of Engineering, 1-33, Yayoi-cho, Chiba City
(Received 15th August,
1984.
Accepted
for Publication
Chiba University
23th October,
1984)
Abstract Boron
trifluoride,
(BDTFB), an
was
insoluble
could
be
because
the
determined of
by
indirectly
1.0
in
by
dioxane
from
the
it
completely
in
weeks.
This
pound
detects
was IPA
decomposition
as
of
decomposed
analytical selectively
the
the
BF3
IPA
which
the
60%
is
of
the
useful
of spectral
as
BF3
cationic
Introduction
Since Schlessinger extended the use of BF3 which was photogenerated from diazonium tetrafluoroborate as the initiator of cationic
mer
polymerization1), many reports have been published on the application of such an initiator to photocurable cationic systems for surface coatings and printing plates2)-4), and to radiation-degradable systems for EB and X-ray resists". The former system involves the use of the photoinitiator in epoxy resisns, and an example of the latter is the radiation initiated depolymerization of polyaldehyde. They are favorable to get high sensitivity through chemical amplification. The amount of BF3 determines the rate of poly-
cured
and
W. by
and
sensitivity
as
important
nium
the
is
by
the
with
pounds9)-12), titative As
•\ 351—
BF3
was
place
in
dimethylamino
2
com-
storage
molecular of
it
the
resolving amount
may
BF3
funcit
much
generated
are of are
many
diazonium
sysdiazo-
reports com-
about
photogene•\ration of
the the
diazonium few
is
boron
in of
There
the
of
Therefore,
photolysis
rate
power of
how
actually
stability
the
property
photodecomposition
on
to
the
depolymerization
catalyst5).
there
polyIn
relates
In
the
the
reaction6)-8).
determine
but study
the
generated
mechanical
compound.
dealing
in-
BDTFB
no
took
the
and by
to
trifluoride tem
been
material.
controlled
tioned
was that
distribution
the
coating
be
was
determined
found
system,
curing
dimethyl-
depolymerization,
M.
obtained
the
BDTFB
hand,
a
a
initiator.
polymerization of
of
have
of
BF3
N-dimethyl-
was
which
or
weight,
p-(N,
BF3
other
BDTFB
merization
1.
to
the
change
the
of
It was
On
directly So
of
of
mole
ring
detected
electrons
20•Ž.
products.
of
be
presence
in
benzene
products.
stability
at
decomposition use
the
storage
that
to
pair
1.0
dioxane
and
thermal
in
dioxane, the
or
3 weeks,
by
out
or
decomposition
complete method
carried
able other
lone
decomposed
containing
not of
to
Then, in
in in
the
was
dispersion
was those
coordination
compound. a
BF3
tetrafluoroborate was
products
with
isopropanol
diazonium compound
decomposition But
by
benzene
diazonium
band
change
solution
detected after
and
characteristic
diazonium
keeping
BDTFB
detected
the a
from the
spectrophotometry.
spectral
When
of
reactant
the
from
in
mole
vestigated
UV of
amino)-fluorobenzene from
photogenerated When
residual
overlapping
compound.
was
quantitatively.
solvent,
determined amino
which
analysed
quanof
BF3. com-
•\
K. HARADA, N. UENO, K. SUGITA and S. SUZUKI
352•\—
pound
is
poor
on
composition,
it
amount
of
catalyze
the
In
paper,
a
was
use
able
to
and
was
of
diazonium
studied,
thermal
the
the
analysis
benzene
storage
of
be
quantitative
by
during
the
to
deout
system.
from
generation
thermal find
trifluoride
tetrafluoroborate
BDTFB
its to
photo-imaging
photogenerated
BF3
of
essential
boron
this
BF3
account is
J. Soc. Photogr. Sci. Technol. Japan
then
the
decomposion
of
investigated
by
analytical
method
above-
mentioned. 2.
Experimental
2.1
Materials Benzene
diazonium
obtained
by
rafluoroborate
aqueous
to
benzene
diazonium
aniline.
The
and
aqueous
used
were
of
of
by
The
extra
Photodecomposition
from
purified
methanol.
were
tet-
solution prepared
precipitates from
materials
was
hydrogen
chloride
recrystallization
2.2
tetrafluoroborate
adding
pure
and
other
grade.
UV
Spectro-
Fig.
photometry Benzene
diazonium
tetrafluoroborate
TFB)
powders
dispersed
vent
(isopropanol
or
with
a
A
part
a of
was
a
of
diluted
measured
with
a
Spectrophotometer was
partly
was
dissolved
3. 3.1
and
is
tion sorption
in
and
are
at
that
275
nm
of
BDTFB persed
the
in
IPA
Fig.
the
absorpAbethyl
were
1.
was
an
dioxane13). trifluoride
measured
The
molar
calculated value
of
to 9.3
in
abbe
6.6
dioxane
literature. of
Tetrafluoroborate
IPA
BF3
nm
and
IPA
powders in
BDTFB
water.
shows
Photodecomposition zonium
BDTFB
of
boron
in
from in
When
BF3
275
dioxane
in
reported 3.2
at
shown
sorptivity
and Beam
residual
with
Spectrum
spectra
etharate
solvent Double
the
dilution
reported
maximum
50
20•Ž.
Discussion
Absorption It
the
Shimazu
UV-180.
Results
at
photodecomposition
decomposed, by
mmƒ³ •~
kept
with
(0.019 (3 ml)
Benzene in
g,
were
in
IPA ƒÃ=6.6
dioxane *
R
. Havey,
Anal.
of
BF3(C2H5)20 -
e =9.3 Chim.
Acta.
at
275
nm
at
275
...... nm*
67,
2448
(1973)
Toshiba
(10
3 cm
sol-
Spectrum
irradiated
lamp, cell
of
solution
was
were
quartz
distance the
products
insoluble
mercury
in
at
an
dioxane),
high-pressure
SHL-100UV, mm)
in
(BD-
1
Dia-
IPA
1 •~ 10-4 irradiated
mole)
diswith
a high-pressure mercury lamp. While irradiation, little bubbles were generated from the surface of powders and BDTFB gradually dissolved into IPA. After complete dissolution of BDTFB powders, an aliquot of the IPA solution was taken and analysed by UV spectrophotometry. UV spectra of decomposition products and some expected model compounds (fluorobenzene; a mixture of fluorobenzene and phenol; and a mixture of fluorobenzene, phenol and boron trifluoride ethyl etherate) are shown in Fig. 2. The spectrum of decomposition products coincided with that of a mixture of fluorobenzene, phenol and boron trifluoride ethyl etherate; absorption bands at 248-270 nm were assigned to fluorobenzene and phenol, respectively. From the spectral intensity, it was estimated that these compounds were produced in a molar ratio shown in Eq. (1) :
Vol. 47,
Studies
No. 5, 1984
on Diazo
Type
Process.
•\ 353•\—
VIII
the fact that BF3 coordinates to the lone pair electrons of the dimethylamino group and that interaction is interrupted between the lone pair electrons and r electrons of benzene ring14) (see Eq. (2 )).
(2) The
quantitative
tempted of
the
the
is
so
form
the
is
the
visible
at
azo
the
dye,
In
was
line,
and
p-
reaction is
occurs
deduced at
order
to
from
405
nm
in
prevent
the
from
being
N-dimethylamino)-fluoroben-
used
instead
BF3
diazonium
be
unsubstituted
compound
p-(N,
with may
N-Dimethylani-
which
region.
When contact
appeared
N-dimethylamino
zene
N,
coupling
peak
coupled,
in
at-
change
former
latter.
the
an
was
compounds.
reactive
absorption
BF3
spectral
the
that
an
N,
Products compounds
the
compound
with
position to
of
of
N-dimethylaniline,
line
Spectra of Photodecomposition of BDTFB and some model
use
dimethylamino
coupled
2
the
diazonium
N,
Fig.
analysis
by
of
N,
N-dimethylani-
photo-generated
from
tetrafluoroborate
was
benzene
determined
quantitatively.
(1)
3.3.1
The
The
spectral
Calibration
Curve
change
of
solutions
of
N-dimethylamino)-fluorobenzene The
sum
of
moles
containing nol
and
mined
to
be
equal
BF3 because
sorption
band at
275
phenol
at
tivity
of
was
nm,
those
of
and
of
(ƒÃ= 6.6)
s =1,700
at
small
When
BF3
nm)
the
zene.
The
and
other 262
nm
;
was
Presence
added
to
(DMA)
or
of
that spectral
a solution p-(N,
(DMAFB)
spectrum
of of
DMA
or
benzene change
As
308
pair
electrons peak
er
lowered.
248
or is
in
ascribed
Fig.
4. of
of It
in
248
BF3
is of
concentration
considthe
was
lone when
no
long-
absorbances
at
concentration 4. is
the
of
The
calibra-
also
shown
plot
fluorobenzene
standard
was
nm
Fig.
of
nm be-
group
fluorobenzene slope
248
to
initial
shown
was
at
fluorobenzene
3].
at
in
• (C2115)2O
spectrum
coordinated
vs.
curve
the
that
minimum
nm
and
BF3
dimethylamino
The
of
the
various shown
peaks and
Fig.
DMAFB
the
calibration
the
of
The
DMAFB
of
has
are
curve
derivative to
with
308
tion
fore,
DMAFB fluoroben-
)'
with is of
to
BF3
of
and
peak N-
maximum
decreased
(7 that
adding
• (C2115)2O
the
similar
ered
by
BF3
concentration
quite
the
IPA
the
nm
DMAFB the
Fluorobenzene
• (C2H5)2O
into
at
in of
[compare
absorp-
with
3.
came
.
in
N-dimethylaniline
changed
nm,
molar
dimethylamino)-fluorobenzene IPA,
262
=1,400
275
and
products
at
M/l)
increased,
photo-
detected of the ab-
other
compared
Photodecomposition Dimethylamino
be
Fig.
reactant
the
10-4
concentrations
deter-
of
not able to of overlapping
(fluorobenzene, ƒÃ
phenol,
N,
mole
fluorobenzene
nm)
BF3
was the
(0.9 •~
phe-
However,
with
275
products
of
products
(fluorobenzene,
to
employed.
generated directly,
3.3
decomposition ring
p-hydroxy-azobenzene)
originally
(BF3
of
benzene
p-(N,
(DMAFB)
of
derivative coincided
with
fluorobenzene. of
regarded fluorobenzene.
the to
be
in
248
nm
from that
of
Therefluorobenzene equal
to
Absorbance
that
K. HARADA, N. UENO, K. SUGITA and S. SUZUKI
•\ 354•\
Fig. 3
Spectral change BF3(C2H5)2O
of DMAFB by adding
J. Soc. Photogr. Sci. Technol. Japan
Fig. 5 Relation between concentration of (CH3)2N
