Note: Descriptions are shown in the official language in which they were submitted.
6~9
63356-1575D
B C ROUND OF THE INVENTION
This application, which is divided out of Application
Serial No. 483,186, relates to certain polymeric products pre-
pared from pyridinium ylides. Application Serial No. 483,186,
relates to a method for preparing articles, including photo-
resists, from polymeric pyridinium ylides by a photolytic
reaction.
The use of photopolymerization reactions in the print
ing and graphic arts fields for the production of relief and
lithographic printing plates has been well kno~m. Suitable
methods for the production of plates for the printing and graphic
industries are described, for example, in Neblette's Handbook of
Photography And Repography, Seventh Edition, pp. 439-40 (1977~.
Typically, a monomeric compound on a suitable plate support
material will be selectively exposed to a source of light so as
to effect a photopolymerization (insolubilization) in exposed
areas. The difference in solubility, between unexposed and ex-
posed (polymerized) areas, permits easy development.
The principles of photopolymerization are also utili~ed
in photoengraving and lithographic plate-making by the use of
long-chain polymers whose molecules are able to crosslink under
the action of light to form a three-dimensional molecular net-
work. Typically, the photo-crosslinked polymer will be in-
soluble, and will be soluble only in powerful
i ~?
)6~9
solvent mixtures of the type used in paint
stripping. Stencils produced by the photo-crosslinking
reaction are photoresists which are highly resistant to
commonly used solutions; solvent development is used to
remove the original long-chain polymer from unexposed
areas.
In U.S. Patent 3,081,168 (issued March 12, 1963
to R.M. Leekly et al.), the production of relief plates
using polyamides as a preformed polymer is described.
Photosensitivity is imparted to the polyamide, which is
carried on a support, by including with the polyamide, a
photopolymerizable unsaturated compound. Following a
selective exposure to light, which induces a decrease in
solubility in exposed areas, unexposed areas are removed
with a developer. Ater development, the base material
(e.g., metal) can be etched by chemical etching or
abrasive blast to form a relief image in the base
material. If desired, an offset plate can be prepared by
coating the photosensitive polyamide composition onto a
hydrophilic support. ~he image obtained upon
photoexposure and development will carry an ink and the
wet support will resist ink.
In the production of plates by resort to
photoreaction chemistryj a reactive and
photopolymerizable monomeric compound will oftentimes be
employed. The compounds are frequently liquid or in a
gaseous form which may hamper efficient handling and the
production of coatings suited to photopolymerization.
Pre~ormed polymers which are photo-crosslinkable may
exhibit limited photo-reactivity or sensitivity.
Accordingly, it will be appreciated that there will be
application in photosensitive plate-making for a
polymeric compound which can be conveniently coated from
an aqueous medium onto a suitable substrate or carrier
material and which can be readily converted, by a
~6~)6~9
63356-1575D
chemical modiflcation induced by exposure to irradiation, to an
insoluble or hydrophobic material.
SUMMARY OF THE INVENTION
. . . _ .
It has been found according to the present invention
that products and articles including a hydrophobic or water-
insoluble protective polymer material can be prepared by subject-
ing a layer or coating of a polymeric pyridinium ylide to a
source of actinic irradiation sufficient to induce a chemical
modification thereof and production of the hydrophobic or water-
insoluble protective polymer material.
Application Serial No. 483,186 relates to methodaspects and provides a method whereby an article carrying a layer
of photosensitive polymeric pyridinium ylide is irradiated
sufficiently to induce a photochemical modification of the polymer
and resulting water insolubility or hydrophobicity. A preferred
method comprises selectively irradiating an article carrying a
layer of photosensitive polymeric pyridinium ylide, to convert
exposed areas to a water-insoluble or hydrophobic material; and
washing from the article, in areas of non-exposure, the unexposed
polymeric pyridinium ylide; thereby to provide an image in water-
insoluble or hydrophobic polymeric material.
Certain novel photosensitive polymeric pyridinium
ylides are the subject of this divisional application, which in
one aspect provides a polymeric pyridinium ylide adapted upon
exposure to actinic radiation to formation of a polymeric N-acyl-
diazepine, said polymeric pyridinium ylide comprising a plurality
of repeating units having the formula
-- 3
. ' ~- ~- . .
~6C~
I 1 63356-1575D
-- C -- C --
C=O
ol3
N-R
C=O
l~3
wherein R is hydrogen, alkyl, aryl, alkaryl or aralkyl and R3 is
a divalent alkylene radical.
Objects of the present invention as defined in this
and the parent application, details, constructions, operations,
uses, advantages and modifications thereof will be apparent from
the following description, taken in conjunction with the illus-
trative drawings of certain embodiments thereof.
BRIEF DESCRIPTION OF THE DR~WING
Figure l is a cross-sectional edge view of a photo-
sensitive article incorporating the polymeric pyridinium ylide of
the invention.
Figure 2 is a cross-sectional edge view of a photo-
sensitive article incorporating the polymeric pyridinium ylide of
the invention carrying an optional metallic layer.
Figure 3 is a plan view on an enlarged scale of a
metallic electrode pattern formed on a substrate material.
Figure ~a is a cross-sectional view of an electrode
pattern taken along the lines 4a-~a of Figure 3 and showing a
~6~64~
63356 1575D
support carrying electrodes having a protective polymeric layer
thereon.
Figure 4b is a cross-sectional view of the electrodes
of Figure 4a with the protective polymer removed therefrom.
Figure 5 is a plan view of an image in hydrophobic
polymer material formed on a substrate material by khe method of
the present invention.
DETAILED DESCRIPTION OF THE INVENTION
__
In the method of Application Serial No. 483,]86 a
layer or coating of polymeric pyridinium ylide is converted by
actinic radiation to a polymeric material exhibiting water in-
solubility or hydrophobicity. The pyridinium ylide polymers suited
to this purpose are polymers which include the pyridinium ylide
moieties of formulas (I) and/or ~
~N~ 3-X- ~N~9-N~)-X-
(I) (II)
O P
wherein X is -C-, -P- , or -SO2-; and Rl is alkyl, aryl, alkaryl
ORl
or aralkyl. These moieties, are a part of the polymer and are
either pendant from the polymeric backbone, as in the case of the
moiety of formula (I) or (II), or comprise a part of the backbone
of the polymer, in the case of the rlloiety of formula (II).
O
Preferred X groups include -C- and -SO2-. Polymers which con-
; tain these pyridinium ylide moieties are for convenience referred
63356-1575D
to hereinafter as polymeric pyridinium ylides.
When a polymeric pyridinium ylide containing the
moiety (I) or (II) is subjected to photolysis, the resulting
chemical moaification (a conversion of the pyridinium ylide
to an N-acyl-diazepine via riny-expansion) is accompanied by
a substantial change in polymer properties. While the
pyridinium ylide polymer is yenerally water-soluble and can be
conveniently coated from an aqueous coating medium onto a
suitable substrate material, the corresponding N~acyl-diazepine
polymer produced upon irradiation is characterized by
- 5a -
`~
~2~6~
insolubility in water, or hydro~hobicity. This
substantial change i~ polymer properties makes possible
the application of pyridinium ylide polymers to the
production of various articles, including photoresists,
stencil coatings, duplicating pads, lithographic and
relief plates, printed circuit boards and chemically
etched electrode patterns on glass or other supports.
The .chemical conversion (N-acyl-diazepine
formation) can be illustrated by resort ~o the following
scheme showing the conversion o~ a polymer having a
preferred pyridium aminimide moiety to the corresponding
N-acyl-diazepine:
ICH3 ICH3
--CH2- ~C-- --CH2-~--
C=O hv C=O
~ >
O O
I I
- t CH~
~CH2 ~C1~2
N-H N-H
C =O ' C =O
.
.
The accompanying changes in physical properties
permit a variety of products to be prepared as mentioned
- hereinbefore. Accordingly, variations in the nature of
the polymer can be used to accommodate particular
60~
applications. According to a preferred embodiment o~ the
invention, the polymer will comprise a backbone having
pendant pyridinium ylide moieties, the polymer comprising
repeating units according to the formula (III)
--C - C--
(IL)rn_l
~ (III)
~ '
wherein L represents an organic linking or spacer group
which serves to link the -X- ~ ~ moiety to the
polymer backbone; and m is the integer one or two.
It will be seen from inspection of the polymer
unit represented by formula (III), that the pyridiniurn
ylide moiety pendant from the polymer backbone may be
attached either directly to the backbone (as where m is
one) or through the organic linking group, L (m is two).
Preferably, the backbone of the polymer will
comprise a plurality of interconnected units
corresponding to the formula
- CH2-C -
where R2 is hydrogen, halogen or alkyl, such as can be
readily provided by ethylenic polymerization of acrylic
or methacrylic monomers.
~26~6~9 -
The nature of organic linking or spacer group L
can vary and, for example, can be a divalent radical such
O o O R O R
~s -C-o-R3-;-~-o-R3-o-; -C-~-R3-; -C-N-R3-o-,
O R
-C-o-R3-N-; -Ae--; or Ar-R3- ~wherein R3 in each such
radical represents a divalent alkylene radical, such as
methylene, ethylene or 1,2-propylene; R is hydrogen,
alkyl, aryl, alkaryl or aralkyl; and Ar represents an
arylene radical such as phenylene or naphthylene). In
each of the L groups containing a carbonyl group, such
carbonyl group will preferably be attached to the
backbone of the polymer. It will be appreciated that the
nature of linking group L, and its molecular
configuration and size, can be varied to influence the
properties of the polymer produced by photo-induced
modification, and the rate of the desired photo-reaction;
and the choice of a suitable linking group may in part be
influenced by synthetic considerations and ready
availability of reactants for production of pyridinium
ylide polymers hereof.
A preferred linking group L has the formula
O H
-C-o-R3-N-
wherein R3 is a divalent alkylene group such as
ethylene. Preferred polymeric ylides having this linking
O
group are the polymeric pyridinium aminimides (X is -C-).
Repeating units of such preferred polymers will have the
formula (IV):
--8--
~6~6~9
C~ 2 -C--
C-O
O
~3 (IV)
N-H
C=O
~
wherein R2 is hydrogen, halogen (e.g., chloro) or lower
alkyl (e.g., methyl); and R3 is alkylene. Polymers
having the repeating units shown in formula (IV) contain
a carbamate structure and can be conveniently obtained by
polymerizing the reaction product of an isocyanatoalkyl
ester (such as beta-isocyanato-ethyl methacrylate) and
N-amino-pyridinium compound. The resulting polymers are
readily converted to a water-insoluble oe hydrophobic
polymer upon irradiation and can be used in the
manufacture of photoresists and printing plates.
The linking group L of the polymers shown in
~- 25 formula (III) can, if desired, be attached to two carbon
atoms of the polymeric chain. A suitable example is the
radical
/ \
\N
CH2
O
~ _g_
:~
4~
derived, for example, from a polymerizable maleimide.
Such a linking group can be present in the repeating unit
of a pyridinium ylide polymer such as is represented by
the unit of the formula
CH - CH -
O=C ~=0
\~
~CH2
H2
0
. . X
N ~)
. ,N ~3 ' .
[~3
If desired, the pyridinium ylide moiety of
polymers useful herein can be incorporated into the
backbone of a polymer. In this case, a suitable
pyridinium ylide moiety is the moiety of ormula
(II), i.e., the ~ -N-X - moiety. A polymer
including the pyridinium ylide moiety of formula (II) as
part of the backbone is illustrated, for example, by
reference to repeating units of the Eollowing formula
(V):
----R4 -X~ 9~R5 ~1~)~N~3X-- ( V)
--10--
~606~9
wherein ~4 is alkylene or arylene; 1~5 is alkylene, such
as 1,3-propylene; and X has the meaning described
hereinbefore. A polymer as represented by formula (V)
can be prepared by reaction of a dicarboxylic acid halide
O O
of the formula Z-C-R4-C-Z where each Z is halo (e.g.,
chloro) and a bis-amino-pyridinium compound of the
formula
H 2 N- ~?~=3 - R 5 {=~ N H 2
A~ A~
wherein R4 and R5 have the meanings aforedescribed and
each A~ is a counteranion, such as chloride.
Another example of a pyridinium ylide polymer
where the formula (II) moiety is present in the polymer
backbone is illustrated by the polymer having aminimide
repeating units of formula (VI)
~ - - R6-N-c-o-cl32-cl32 ~ N~-N-C-N - (VI)
Such a polymer can be prepared by reaction of a
diisocyanate of the formula R6-~N=C=O)2 wherein R6 is
alkylene or arylene with a l-amino-pyridinium compound of
the formula
A~
Ho-c~32-cH2 ~ ~ NH2
wherein ~ is a counteranion (e.g., chloride).
If desired, a pyridinium ylide polymer wherein
the pyridinium ring is attached to the backbone of the
~6[3Ç~
polymer can be em~loyed ilerein. An example o~ such a
polymer is a polymer comprising repeating units of the
formula (VII)
- CH2-C -
~N~
t (vII)
X
R7
wherein R7 is alkyl; alkoxy; aryl (e.g., phenyl); alkaryl
(e.g., tolyl); or aralkyl (e.g., benzyl); and X has the
meaning described hereinbefore. Such a polymer can be
prepared, for example, ~rom poly(4-vinylpyridine) by:
derivatization of the poly(4-vinylpyridine) to provide
the l-amino-pyridinium (using hydroxylamine-O- sulfonic
acid and hydriodic acid treatments, according to the
techniques described in Organic Syntheses, Collective
Volume 5, John Wiley and Sons, pp. 43-45); and reaction
of the resulting polymer with an acylating agent of the
formula R7-X-Z wherein R7, X and Z have the
meanings previously ascribed. This reaction scheme is
illustrated by reference to the following:
--CH ~ CH2- H-- --CH2-CH-- --CH2--CH--
2~3 K 2 C0 3 `~ 3 R 7 - X - Z
30 NH NH2 X
R7
Examples of acylating agents that can be used
in reference to the above-described reaction scheme
include:
-12-
;
~L2~
CIJ3-S02-Cl; (Cll~O) 2-P(O!Cl; C113-C(o)Cl; or the esl:ers or
anhydrides thereof. Phenyl isocyanate can also be used.
If desired, hydroxy-containing polymers having
ylide groups attached thereto through an ether linkage
can be prepared by reaction of a polymer having a
plurality of hydroxyl groups (e.g., cellulose,
hydroxyethyl cellulose or hydroxypropyl cellulose) with,
for example, a compound of the formula Cl-CH2-e-N-
using the procedure described in U.S. Patent 4,016,340
(issued Apr. 5, 1977 to ~I. S. Kolesinski et al.).
The polymeric pyridinium ylides containing the
essential pyridinium ylide moieties of formulas (I)
andJor ~II) can, if desired, contain substituent groups
on the pyridinium nucleus. Alkyl, aryl, halo, nitro and
other substituents can be used to modify the properties
of the polymeric pyridinium ylide as desired. It will be
appreciated that the nature of the substituents present
may alter the absorption characteristics of the
pyridinium ylide moiety and may influence the conditions
required to e~fect the desired conversion to the
corresponding polymeric N-acyl-diazepine. Any
substituent groups which do not negate or otherwise
adversely interfere with the desired conversion can,
however, be employed. One or more methyl groups can, ~or
example, be used and examples of such
substituted-pyridinium moieties include 2-picolinium,
3-picolinium, 4-picolinium and 3,5-dimethyl-pyridinium.
Two substituent groups can taken together complete a
cyclic structure such as a quinolinium or isoquinolinium
structure. As used herein, the term "pyridinium" is used
to include substituted-pyridinium moieties, such that,
moieties which may properly be termed picolinium,
quinolinium or the like, will be considered pyridinium
3S moieties as the term is used herein.
1~0649 63356-1575D
Among examples of polymeric pyridinium ylides that can
be utilized in the method of Application Serial No. 483,186 are
polymers which include repeating units hav.ing the following
formulas:
ICil3 ICH3
CH2-,C - - CH2-C -
C=O C=O
N~ N-il
~,N~0 ( Ci~ 2 ) 5
(VIII) ~ l=
- N~ (IX)
''''' '' (~ .
CH3 C~13
- CH2 IC - - Cil2-C -
1=0 iC=O
I N-H
~CH2 Ci H2
ICil2 CH3- 111
l i
Cl=O C=O
N~) N(~)
(X) ~ ~ (XI)
--1'1--
~l26~
--C C-- jC~1 3
O= C=O --CH2-C--
\ N/ C=O
C~12 1
CH 2 ~CII 2
O C ~1 2
C=O N-H
N (3 C = O
(XII) ~ N~3 (XIII)
--CH2-CII-- --C112-CH--
C=O C=O
o O
CH 2 IC~I 2
C112 C=O
N- H ~3
C = O N~
( X I V) ~,5 ( XV)
~J
--C~ 2 -C~--
--CH 2 -Cll--
o~o ~
N~ N~
(XVI) O=S O
tXvII)
CH2 -CH
--CH 2 -CH--
~ C=O
N-H
C~O Cll3-C-CH3
N~3 C= O
(XVIII ) ~ ~ (XIX
--16--
~606~
-- CH -CH -- -- CH2-CH ---
~N~ ,J
1 2 N~)
C=O CH30-P=O
OCH 3 ~ XXI )
tXX)
--CH-CH--
N~
C 2 Ej~
( XX I I ) lloH 2 E~ \~ ( XX I I I )
c=o 11 ~
~3 CH2-0-CH2-C-N-N~)
N~E\
~3 '
O O
3 N-C-O-CH2-CH2 ~ -N-C-N
H H (XXIV)
- 17 -
The polymers employed herein can be
homopolymers or copolymers, including graft or block
copolymers. The copolymers can contain units provided by
copolymerization with various ethylenically unsaturated
monomers such as alkyl acrylates, alkyl methacrylates,
acrylamides, and methacrylamides. In general, these
comonomeric units are utilized to provide particular
predetermined properties to the polymer, such as
coatability and viscosity and, in particular,
polymerizability and controlled photo-reactivity.
In general, the polymers employed herein will
contain the photo-reactive pyridinium ylide repeating
units in an amount suficient to allow for appreciable
conversion from a relatively water-soluble condition to a
condition of relative insolubility or hydrophobicity. In
the copolymers, the proportion of photo-reactive units to
total units will vary depending on the nature of the
particular photo-reactive units employed, the nature of
the comonomeric or any polymeric material that may be
utilized therewith, and upon the particular application
and product requirements or characteristics desired.
A preferred comonomeric unit that can be
included in a polymer of the present invention is the
methacrylate unit obtained from the polymerizable
methacrylate monomer of the formula (XXV)
IC~13 1l 1l
C~12=C C-o-c~l2-c~l2-N-c-o-cl~2-cH3 (XXV)
H
This monomer is readily polymerizable with the
polymerizable pyridinium ylides hereof. A preferred
copolymer is a copolymer of this monomer and the
-18-
6~
pre:Eerred pyridinium aminimide monomer corresponding to the
repeating unit of formula (XIII). Good results are provided
UpOI- irradiation of this preferred copolymer. Other ethylen-
ically unsaturated comonomers can, however, be used and examples
of such include acrylic acid; methacrylic acid; 2-acrylamido-
2-methylpropane sulfonic acid; N-methyl acrylamide; methacryl-
amide; ethyl acrylate; butyl acrylate; methyl methacrylate;
N-methyl methacrylamide; N-ethyl acrylamide; N-methylol-
acrylamide; N,N-dimethyl acrylamide; N,N-dimethyl methacryla-
mide; N-(n-propyl) acrylamide; N-isopropyl acrylamide;
N-(B-hydroxy ethyl) acrylamide, N-(~-dime-thylamino) acrylamide;
N-(t-butyl) acrylamide;
N- [~- (dimethylamino)ethyl]methacrylamide;
2-[2'-(acrylamido)ethoxy] ethanol; N-(3'methoxy propyl)-
acrylamide; 2-acrylamido-3-methyl butyramide; acrylamido
acetamide; methacrylamido acetamide;
2-[2'-methacrylamido-3'-methyl butyramido]acetamide; and
diacetone acrylamide.
Polymers hereof containing the repeating units of
formulas ~I) or (II) pendant from the backbone thereof can be
readily prepared by polymerization in known manner of the
corresponding polymerizable monomeric compound of the formulas
(XXVI) or (XXVII) as Eollows
-- 19 --
~6~9
-- C=C -- C=C -
( I ) m- 1 ( ) m- 1
or L
( XXVI )
N 6
`il N ~)
I (XXVII)
R7
- 19a -
" ~26~:316~9
wherein X, m, L and l~7 have the mearlings hereinbefore
described. Various preparative routes to the
polymeriza~le monomers can be used depending upon the
nature of the L and X moieties desired in the polymer;
and suitable synthetic methods will be known to those
skilled in the art. For example, preferred polymerizable
monomers useful in the practice of the present invention
have the formula
1~
R2 ol H O
CH2 = C - C - O - R3- N- C - N~- N ~
wherein R2 and R3 are as previously defined. These
compounds can be prepared by the reaction of an
isocyanato ester of acrylic, methacrylic or
2-chloroacrylic acid having the formula
R2 o
CH2 ~ C - C - O - R3 - N = C = O
(wherein R2 and R3 are as previously defined) with a
l-amino-pyridinium salt of the formula
~ ~- NH2 A~
wherein A~ represents a halide counteranion such as
chloride, bromide or iodide. The isocyanatoalkyl ester
starting materials are known compounds and their method
of preparation is described, for example, in U.S. Patent
-20-
~.26~
2,718,516 (issued Sept. 20, 1955 to N.M. I~ortnick).
SimilarLy, the l-amino-pyridinium salts and their
preparation are described in Organic Syntheses,
Collective Vol. 5, pp. 43-45. The reaction is
illustrated by reference to the Eollowing reaction scheme
which shows the reaction of the prepared 2-cyanatoethyl
methacrylate and l-amino-pyri.dinium ch~oride in the
presence of potassium carbonate:
1 0
~113 C1-13
CH2= ,C CH2= lC
C=O C=O
CH2 + ~ K2CO3 CH2
l H2 ~H2 CH2
N N-H
ll l
Cl C=O
O N
~N~
The ethylenically unsaturated polymerizable
monorners can be polymerized using known polymerization
techniques such as solution polymerization using free
radical or redox initiation. Suitable initiators include
azobisisobutyronitrile and azo-bis-4-cyano-pentanoic
30. acid, although other catalysts can be employed.
Condensation-type polymers in which the
pyridinium ylide moiety is a part of a polymeric backbone
can be prepared by resort to known polymerization methods
used in the preparation of condensation polyr~rs.
3S Solution polymerization or interfacial polymerization
-21-
~ 6~
techni~ues can be used dependinc~ upon the nature o~ the
particular monomers used in the polymerization.
The polymeric pyridinium ylides can be
converted to their corresponding N-acyl-diaæepines using
a source of actinic irradiation of sufficient intensity.
In general, ultraviolet radiation provides good results;
other sources of actinic irradiation can, however, be
employed. It will be appreciated that the amount of
irradiation required to eE~ect the desired conversion
will vary with the wavelength and the intensity of the
radiation source and will vary with the absorption
properties of the p~ridinium ylide moiety of the polymer
employed. The absorption properties, can vary with the
presence or absence of substituent groups on the
pyridinium nucleus. Appropriate exposure times and
conditions can be employed depending upon these
considerations. In general, a source of ultraviolet
irradiation can be used in conjunction with exposure
times in the range from less than one to about 30 minutes
or more.
The novel polymers produced from the
photosensitive ylide polymers by photolytic reaction
contain N-acyl-diazepine moieties of the formulas (XXVIII)
and ~**~ C~X~)
~-X~ X-
~XVIII) (XXIX)
The polymers containing these moieties are referred to
herein for convenience as N-acyl-diazepine polymers.
-22-
~ 06~9
. ,
'I'hese ~olymecs have the structure o~ th~ corre>sponding
pyridinium ylide polymers described herein, except for
the presence of N-acyl-diazepine moieties of formulas
~XXVIII) and (XXVIX) in place of the corresponding
pyridinium ylide moieties (I) and (II) of the precursor
polymers. Examp1es of repeating units of polymeric
N-acyl-diazepines of the invention include the following,
formulas (XXX~ to (XXXIV):
R2
C-C - CH2-lC -
. ~L)m-l tL)m-l
X X
(XXX) ~ ~ (XXXI)
R2 CH3
CH2-C~-- CH2-C
Cl =O C=O
O O
3 (1~2
N-H ICH2
C=O N-H
C=O
35(XXXII) ~ ~ (XXXIII)
-23-
~L26~6~9
~ 5 ~ -X -
- ~4-X- ~ ~ R ~ (XXXIV)
It will be noted that the photolysis of
aminimides derived from pyridines, and the production of
diazepines therefrom, are described by W.J. Mc~illip et
al., in Chemical Reviews, Vol. 73, No. 3, pp. 272-273
(1973). The formation oE pyridine and nitrene
side-reaction products (and the effects of triplet
photosensitizers such as eosine or 3,4-benzopyrene on
such formation~ are also described therein. It will be
appreciated that nitrene and pyridine side-reaction
products may also be formed in connection with the
photolytic reaction employed in the practice of the
present invention. If desired, a triplet sensitizer can
be employed in combination with the polymeric pyridinium
ylides of the present invention so as to promote nitrene
or isocyanate formation and the production therefrom of
cross-linkiny reactions (by reaction of nitrene or
isocyanate moieties with compounds having an active
hydrogen atom). Accordingly, triplet sensitization can
be employed, if desired, to modify the physical
properties of the polymeric N-acyl-diazepine produced by
the practice of the present invention.
The polymeric pyridinium ylides can be used for
a variety of purposes, including treatment and
hydrophobization of surfaces. Thus, a layer of the
polymer can be applied from solution to a suitable
substrate which is then subjected to exposure to a source
of irradiation sufficient to effect the desired
conversion of the ylide to the corresponding N-acyi
diazepine. Water can be employed and will be a preferred
solvent material for the preparation of a coating
-24-
.
~6~49
com~osition which can be collveniently applied to th
substrate by spraying, dippinc3, roll coating or the
like. Other solvents can, however, be used and examples
of such solvents are methanol, ethanol and
trichloromethane. A coating composition suited to
application to various substrate materials will typically
contain the desired pyridinium ylide polymer in a
concentration of about 3 to 43 by weight, although other
concentrations can be used depending upon the particular
polymer employed, the nature o~ the solvent utilized, the
method of application and the nature of the particular
substrate. Various additives such as surfactants,
coating aids, viscosity-controlling agents, UV
stabilizers, photoinitiators, triplet sensitizers or the
like can be included, provided that such agents do not
interfere with the desired conversion of the pyridinium
ylide compound to the corresponding N-acyl-diazepine.
The polymers can be used or the treatment of
substrates such as glass, metal, plastic, such as
polyethylene terephthalate or cellulose acetate, or
fabrics. Sheets, swatches, scrims, ropes or other fibers
can be sprayed, dipped or otherwise coated with the
polymeric ylide compound and can be, then, subjected to
actinic irradiation to provide a polymeric
(N-acyl-diezepine) surace exhibiting insolubility,
hydrophobicity or water repellency.
The resistance of the irradiated polymeric
materials to water and other solvent materials, including
solvent etching materials, allows for the use of the
pyridinium ylide polymers hereof in the production o
articles wherein the irradiated polymer comprises an
image pattern. Thus, a layer of pyridinium ylide polymer
on a suitable substrate material can be exposed to
actinic irradiation in an imagewise manner to provide a
-25-
6~9
recordation or image of the subject i~ polyrneric
N-acyl-diazepine. Exposure of the layer of pyridinium
ylide polymer can be accomplished through a negative, a
photomask or the like. Unexposed areas can be removed by
dissolution in water to provide the desired image in
polymeric N-acyl-diazepine.
In FIG. 1 is shown in cross-section an edge
view oE an article 10 of the invention including a
suitable support material 12 carrying a photosensitive
layer 14 of a polymeric pyridinium ylide. Support
material 12 can be glass, metal, plastic, cloth or any
like substrate material to which the polymeric pyridinium
ylide can be suitably applied, as by coating, dipping or
the like, and which can be subjected to irradiation for
conversion of the pyridinium ylide polymer to the
corresponding N-acyl-diazepine. The nature of the
support will normally be determined by the particular
application for the product. Thus, a metallic support
material may be preferred for the production of
lithographic or like printing plates while glass or
plastic support materials such as polyethylene
terephtha]ate may be preferred for the production of
electro-optic display or like articles. The polymeric
pyridinium ylide layer 14 can comprise any of the
photosensitive polymers as described herein.
~ rticle 10 carrying photosensitive polymer
layer 14 can be subjected to any source of radiation
suficient to convert the ylide polymer to an
N-acyl-diazepine as described hereinbefore, to provide
any of a variety of products. If desired, the
irradiation can be applied to the surface of
photosensitive polymeric layer 14 in a non-selective
manner so as to provide article 10 with a hydrophobic or
waterproof layer 14. This will be appropriate where, or
example, a garment or other protective fabric material 12
-26-
1260~i~9 ~
is desirably rendered hydrophobic or waterproo~.
According to certain preferred applications for
the pyridinium ylide polymers hereof, the polymer will be
irradiated selectively so as to provide a pattern or
image in polymeric N-acyl-diazepine. In FIG. S is shown
a plan view of an article 40 comprising a support
material 42 carrying an image 44 in polymeric
N-acyl-diazepine. Such an article can be conveniently
provided, or example, by coating a substrate or support
material 42 with a layer o~ polymeric pyridinium ylide.
A stencil or mask corresponding to image 44 can be
superposed upon the polymeric pyridinium ylide layer.
Exposure of the polymer layer, through the stencil or
mask, effects the desired N-acyl-diazepine conversion
and, provides a water-insoluble or hydrophobic area 44.
Rinsing or washing of the article in water or other
solvent results in removal o~ the water-soluble
pyridinium ylide polymer from unexposed (shielded) areas
42 so as to define the desired image.
If desired, hydrophobic image material 44 can
be dyed or otherwise colored with material having an
affinity for hydrophobic materials. In this case,
support material can be composed of hydrophilic material
so as to permit selective dyeing of image area 44 to the
exclusion of the dyeing of support material 42. The
resulting article can be used as a plate in duplication
or like printing methods.
In FI~. 2 is shown a preferred article 20
suited to application in the production of a photoresist,
electrode pattern or printed circuit. Shown on support
22 (comprised of glass, insulator board or the like~ is a
layer 26 of metal or other material that can be suitably
etched by physical or chemical means. Examples of such
materials include copper, silver, indium tin oxide and
iron/nickel alloy. 'rhe thi.ckness of metal layer 24 can
~60~9
vary with the nature oE the metaL and the intended
application. On metallic layer 26 is a layer 28 oE
photosensitive polymeric pyridinium ylide.
In FIG. 3 is shown an article 20A having a
metallic electrode pattern 24 formed on a support
material 22. The pattern, comprised of metal and a
protective overlayer o~ polymeric N-acyl diazepine, is
formed by the method of the present invention from
article 20 shown in FIG. 2. Article 20 is selectively
irradiated through a stencil or photomask according to
the pattern defined by area 24 in FIG. 3. Radiation
sufficient to convert the polymeric pyridinium ylide to
the corresponding N-acyl-diazepine polymer is employed.
Removal of the mask and immersion of the photo-exposed
article into a metal etching bath effects removal (in
unexposed areas) of water-soluble pyridinium ylide
polymer 28 and underlying metal 26, leaving on support
22, the desired electrode pattern 24.
In FIG. 4a, there is shown in cross-section,
along the lines 4a-4a of FIG. 3, the article 20a.
Metallic electrode~material 26 is protected by
hydrophobic N-acyl-diazepine polymer material 28a. If
desired, polymeric material 28a can be removed from the
metallic electrode material 26 by dissolving the polymer
in an organic solvent such as dimethylformamide. The
resulting article 20b is shown in FIG. 4b.
Example 1
To a mixture of three grams of
l-amino-pyridinium chloride in 45 mls. of ethanol and
seven grams of powdered anhydrous potassium carbonate,
was added (with stirring and over a period of one-half
hour) a solution of 3.6 grams of 2-isocyanato-ethyl
methacrylate in ten mls. of tetrahydrofuran, absolute.
The resulting solution was filtered and evaporated to
dryness. The residue was dissolved in a 100/15 mixture
-2~-
0649
(by volume) o~ tLichloromethane and methanol and the
resulting solution was filtered through a short column
containing 15 grams of silica gel. The production
fractions were collected, evaporated to dryness and
S recrystallized from methyl acetate. The product, a white
crystalline solid, was a monomer having the formula
CH3 O H O
C!12 = C--C - O - CH2 - CH2--N - C - N - N~3
lS Molecular structure was confirmed by thin layer
chromatographic and nuclear magnetic resonance technques.
Example 2
To a solution of 2.06 grams of
l-amino-pyridinium chloride in 35 mls. of ethanol, were
added seven grams of powdered anhydrous po~assium
carbonate. To the resulting mixture, was added a
solution of 1.8 grams of methacryloyl chloride in five
mls. of tetrahydrofuran, absolute. The addition was
accomplished with vigorous stirring, and in a manner to
maintain the observed purple coloration. Upon completion
of the addition, the resulting solution was filtered and
evaporated. The resulting solid product was
recystallized twice, using acetone, to yield 1.75 grams
of white needle-like crystals (70~). The product was a
monomer having the formula
C~13 3 ~ ~
-29-
- ~ :a2!606~s
The monomer showed good solubility in water, methanol,
trichloromethane; slight solubility in acetone and
, ~ . . .. . .
tetrahydrofuran; and insolubility in hydrocarbons.
Molecular structure was confirmed using thin layer
. . .
chromatograllic and nuclear magnetic resonance
techniques.
Example 3
A homopolymer of the monomer of Example 1 was
prepared in the following manner. The monomer (0.7
gram) was dissolved in 8 to 10 mls. of distilled water in
a polymerization tube and 30 mgs. of
azo-bis-4-cyano-pentanoic acid were added. Oxygen was
removed in conventional manner by a repeated sequence of
freezing and vacuum steps. The tube was sealed under
vacuum and polymerization was effectd by heating the tube
to a temperature of from 64 to 70C overnight in a
bath. The resulting polymer was precipitated by
introducing the product into a 20- to 50- fold
(vol./vol.) volume of acetone and the polymer was
recovered.
The polymer was also prepared in a
polymerization tube in the same manner, except that, the
polymer was precipitated into tetrahydrofuran and
recovered. In each case, the resulting polymer showed
solubility in water, methanol, ethanol and
trichloromethane.
Example 4
A homopolymer containing repeating units of
formula (XI) was prepared using the procedure as set
forth in ~xample 3. The monomer used for the
polymerization was prepared by the reaction of
N-(2-hydroxypropyl)-methacrylamide and
N,N'-carbonyl-diimidazole; and the reaction of ~he
resulting amido with l-amino-pyridinium chloride in the
presence of potassium carbonate, to convert the amido to
-30-
~o~
the pyridinium aminimi(ie monomer. Ihe homopolymer
prepared by polymerization of the monomer showed
solubility in water, methanol, ethanol and
trichLoromethane.
Example 5
In a polymerization tube, 336 mgs. o the
monomer of Example 1, 267 mgs. of the monomer of formula
(XXV), and 9.3 mgs. of azo-bis-4-cyano-pentanoic acid
were dissolved in seven mls. of a 1:1 (by vol.) mixture
of water and methanol. Oxygen was removed using a
repeated sequence o~ freezing and vacuum steps, and the
reaction tube was sealed under vacuum. The tube was
heated to 64C in a water bath overnight. The solvent
was removed from the resulting polymerization product by
lS evaporation and the residue was taken up into ten mls. of
trichloromethane. The copolymer was precipitated into
about 400 mls. of tetrahydrofuran. The slightly yellow
polymer was collected and dried in a vacuum oven at 45C
Eor three hours. The product (450 m~s.; 75~ yield) was a
copolymer having the formula:
., . .. ~ . . ... . . .. . .
- CH3 CH3
t
C=O 0.5 C=O 0.5
O O
Cl H2 ICH2
C~H2 ICtl2
N-H N-H
C=O C=O
N~ O
~N~ CH2
~ C~3
-31-
I`he coL~olymcr showed solubility in water, methanol,
ethanol, and trichloromethane; and insolubility in
acetone, tetrahydrouran, ether and ethyl acetate.
Example 6
This Example illustrates the production of a
pattern of iron-and-nickel alloy on a glass substrate.
Samples of glass plate material (2.5~ x 2.5
cm.) having, on each, a layer of sputtered
iron-and-nickel magnetic alloy (thickness about one
micron) were cleaned with methanol. A four-percent (by
weight) solution of the copolymer of Example 5 was used
to spin coat a layer of polymer onto the metal surface of
each of the glass plate samples. Samples were coated
using water as the solvent. Other samples were coated
using trichloromethane or methanol. Spin coatiny was
performed at about 2000 rpm for two minutes.
Each sample was then selectively exposed and
processed in the following manner. A resolution target
(a photomask) was positioned over the polymer-coated
sample so as to permit exposure of areas not covered, and
to prevent exposure of masked areas, according to the
pattern of the mask. The masked sample was then exposed
for 20 minutes to the irradiation of a 12-watt long-wave
(366 nm.) ultraviolet lamp. The mask was removed and the
sample was placed into an etching bath of commercially
available etchant (Nickel Etchant, Type I, Transene
Company, Inc. Rowley, Massachusetts) diluted 1:3 with
water. Polymer (pyridinium ylide) and underlying
metal, in the unexposed areas of the sample, were removed
from the sample by the action of the etching
composition. Conversion of polymeric pyridinium
aminimide to the corresponding N-acyl-diazepine, in areas
of exposure, provided protection of the underlying metal
against removal by ~he tching bath. The result wa.s a
,~ :
~ -32-
3LZ60649
product l-avinc~, in ex~osed areasr a metallic p~ttern
corresponding to the pattern of the mask.
Example 7
This Example illustrates the production of a
copper pattern on printed circuit board material.
An insulator board material having a layer of
copper thereon (a commercially available material used
for the production of urinted circuit boards~ was treated
in the following manner. Samples of the board material
(2.54 x 2.5q cm.) were spin coated (over the copper-clad
surface of the board) with a solution oE the copolymer of
Example 5, using the procedure described in Example 6.
The samples were then masked and photoexposed as
described therein. Upon removal of the mask, the samples
were placed into a bath of aqueous ferric chloride
etching material. Areas of polymeric pyridinium
aminimide and underlying copper were removed (in
unexposed areas) by the effect of the ferric chloride
etching bath. Conversion of the polymeric pyridinium
aminimide to the corresponding N-acyl-diazepine (in
exposed areas) provided protection for the underlying
copper against removal by the etching bath. The result
was a printed circuit board having a copper pattern
thereon corresponding to the pattern of the mask.
Example 8
This Example illustrates the production of an
image in N-acyl-diazepine polymer on a silicon wafer
material.
Samples of commercially available silicon
wafers were spin coated with a 3% solution of the
copolymer of Example 5. Samples were coated using water
as the solvent; other samples were coated using
trichloromethane. Spin coating has performed at 2000 rpm
for two minutes. The coated silicon wafers were exposed
through a resolution target, using a 12-watt ultraviolet
126~6~9 63356-1575D
(3GG nm.) lamp. 1~xposure times ranc3c-1 ~rom 21 to 25
minutes depending upon intensity. rhe photoexpos~(~
wafers were immersed into a water bath for about five to
ten seconds to remove pyridinium aminimide polymer in
unexposed regions. The result was an image in
N-acyl-diazepine polymer of about 0.05 micron thickness
corre5ponding to the pattern of the resolution target.
The image showed good resolution of lines of 2.5 micron
spacing.
Adhesion of the polymeric image to the wafers
was evaluated by sticking a strip of Cellophane*tape onto
the polyl~r image; removing the tape therefrom; and
inspecting for evidence of removal of polymer image.
Inspection showed no evidence of such removal.
Example ~
Usin~ the method described in Example 8, images
were prepared on ~uartz and Cellophane substrate
materials from the polymers of Examples 3, 4 and 5.
Similar results were obtained in each case in that images
of the resolution target in N-acyl-diazepine polymer were
recorded on the substrate maerials. Each of the samples,
using the adhesion test described in Example 8, showed no
evidence of removal of image upon removal of the
~ellophane*tape.
Example lO
This Example illustrates the use of a
pyridinium aminimide polymer for the hydrophobization of
a substrate surface.
Samples of quartz and Cellophane sheet material
were coated with polymers of Examples 3, 4 and 5, using
the method described in Example 8. The samples were
irradiated non-selectively, i.e., without a resolution
target or mask. The polymeric pyridinium aminimide
coating was in each case converted by the photoexposure
to a corresponding N-acyl diazepine polymer exhibiting
*Trade Mark
-3q-
~26C~6~
hydrophobicity and water repellency. ~pplication oE
water to the exposed polymer surface and tilting thereof,
showed the beading and roll-off without a remaining trace
o the applied water. In contrast, similarly coated
samples which were not photoexposed, showed spreading
(wetting) of added water and evidence of dissolution of
the pyridinium aminimide polymer.
-35-
