CA1038537A - Polymers comprising 2-pyridone substituents and compositions thereof - Google Patents

Abstract

Abstract of the Disclosure This invention relates to a photo-cross-linkable polymer con-taining units each having a 2-pyridone side group. The invention also relates to a photosensitive copying material including the novel photo-cross-linkable polymer.

Description

~03~gS37 This invention relates to photo-cross-llnkable polyme~s, and to the use of such poly~ers in photosensitive copying compositions and copying materials.
German Offenlegungsschrift No. 1,570,224, discloses the use, in copying compositions and copying materials, of photosensitive polymers which contain coumarin side groups. These polymers dissolve in only a limited ~ ;
number of organic solven-ts, so that only this limited number of solvents can be used to develop copying materials produced with these polymers. Further~
more, it would be desirable to be able to produce copying materials having a greater photosensitivity than that possessed by these known polymers.
German Offenlegungsschrift ~o. 2,310,307, proposes the use of photo-cross-linkable polymers having 2-pyrone side groups and these polymers do not have the above-mentioned disadvantages.
According to the present invention there is provided a photo-cross-linkable polymer containlng units each having a substituted or unsubstltuted

2-pyridone side group.
The pyridone groups may be linked to the main polymer chain either directly or by linking members. The pyridone groups additionally may be substituted by one or more alkyl groups having from l to 4 carbon atoms and or by ons or more halogen atoms, preEerably chlorine or bromine atoms. The preferred alkyl group is the methyl group; particularly preferred are pyri-done groups which carry a methyl group in the 4-position of the pyridone ring.
In a preferred polymer of the invention, the polymer comprises from about 5 to 100 mole % of polymerized vinyl or vinylidene units each of which is linked to the radical of a 2-pyridone compound through a direct covalent ; ;~
bond, an ester group, an amide group or an acetal group, and ~rom about 95 to 0 mole % of comonomer units. In a further preferred embodiment3 the ~ ~ -polymer comprises from 10 to g0 mole % of said vinyl or vinylidene units and from 90 to 10 mole % of comonomer units. The comonomer units may be units of ethylene, vinyl esters, acrylic or methacrylic esters, -amides or -nitriles, maleic acid anhydride or vinyl heterocyclic or vinyl aromatic ~ - 1 - ,.~'' '' .
f' ~f~

compounds which optionally contain a second polymerizable group.
In a preferred polymer of the invention, the units containing the .
2-pyridone group have the general formula~

,,~''~,:`.,', .: , . ~ . ' - la - .

K-2287 ~
~ ~38537 ~-C CH23 (B) n CH C
N~

~ .
wherein~
Rl, R2, R3, R4, and R5, which may be the same or different, each represents hydrogen, ha.logen, preferably :~
chlorine, or an alkyl group having from 1 to 4 carbon atoms, preferably a methyl group, A represents a direct covalent bond or one ..
of the groups -CONH-, -CQO-, -OCO-, -O-CHOH-, or -O-CH-O-, wherein each ~ ;
oxygen atom of the last-named group is linked to a unit of the basic:chain, : .
B represents an alkylene group having from 1 -to 4, preferably 1 or 2, carbon atoms, and 1 - ~
n ls. O or l. ~. : :
The link with the polymer chain may he at the 1-, 3-, 4-, 5-or 6- position of the pyridone ring. It preferab.ly is at the 1- position, ; . ;
since many.representatives of this type are particularly easy to produce. .:
Any straight-chain or branched, but not oross-linked, ~ homopoly~
- mer or copolymer is suitable as the polymer chain, for example, poly~
ethylenes or polymers produced from substituted ethylenes which, .:::
: . ~ .
therefore, have a continuous carbon chain, and polyesters, polyamides .~
. . ;~ ..
o r polyethers, or copolymers thereof. - , ' .' -- 2 -- :: :
,~ I ' , . ;~,' , . . . .

K-2287 ` ~:
f~llDK ~
The photo-cross-linkable polymers that are preferred, particu~
Iarly because of the ease wlth whlch they can be produced, are those : .
produced from monomeric 2-pyridones which contain a vlnyl or vinyli~
dene group, or those which contain units derived from such 2-pyridones. . ~ ;
Monomeric 2-pyridones of this kind are, for example, acryl esters and preferably, methacryl esters of 2-pyridone alcohols j which can be ` .; ~;
readily produced by known methods; also preferred are acid amides such as can be produced, .for example, from 2-pyridones having an amino ~ ;
group by reacting them with acrylic acld or, in particular, methacrylic ;~
acid. Po.lymers in which the pyridone group is to be attached directly .
to the main po.lymer chain may be produced Erom monomers which con- -:
taln a vinyl group .ILnked directly to the pyridone ring. ~ : .: .
Further polymers of the lnvention are polymerlc polyhydroxy ;~
compounds, all or some of the hydroxy groups of which are esterLfied with 2-pyridones carrying carboxylic groups, or are aceta.lized with . , ~ . .
2--pyridones carrying aldehyde groups, as well as polymers which con-.. tain carboxylic acid groups some or all of which are esterified with 2-pyridones carrying a hydroxy group, or whLch have been converted into . ~ :
amides with 2-pyridones carrying an amino group. -~
,; "
Because of their good so.lubility, adherence and mechanical properties, preference is given to copolymers of the above-mentioned ;~
vinyl- or vinylidene- group containing 2-pyridones with ethylene or ;: substituted ethylenes, and particularly with acry.lic acid or methacrylic acid derivatives, especially with aromatically substituted ethylenes, for example, styrene, vinyl toluene, chlorostyrene or mixtures of two ; .:
or more thereof . The molar ratio of 2-pyridone units to comonomer units i .
depends upon the desired physical properties of the polymer and upon ,' ~. ;
the required degree of cross-linking upon exposure to light.
~: .

~.

- 3 - ``

K-2287 ~ ~
~03~S37 ~ ~
Even additions of one mole % of a comonomer may have a marked effect, while on the other hand copolymers which contain only 5 mole %
or less of 2-pyridone units are still capable of photo-cross-linking.
Generally, however, the proportion of pyridone-containing monomer is between 90 and 10, and preferably is between 75 and 25 mole %.
The polymers of the invention may be produced, depending on their type, by a) polymerizing by known techniques 2-pyridones which contain at least one polymerizable vinyl or vinylidene group, preferably wlth the aid of a free-radical initiator, and optionally together with a non-photosensitive or photosensitive copolymerizable vinyl or vinyli-dene compound, or b) by esterifying or transesterifying, or acetalizing or trar~sacetalizing potymers which carry free, esterified or acetalized hydroxy groups, with 2-pyridones carrying a carboxyl group or an alde-hyde group, using known methods, or by esterifying or transesterifying polymers, which contain free or esterified carboxyl groups, carboxyllc , acid chloride groups or carboxylic acid anhydride groups, with 2-.
pyridones carrying a hydroxy group, or by reacting the latter polymers with 2-pyridones containing an amino group.
The polymerization mentioned under (a) above may be begun by the usual initiators, e.g. peroxides or azo compounds. It is preferably carried out In a solvent which is unaffected by the reaction conditions, e.g. in benzene, butanone, or dimethyl formamide. Particularly when ;
working with small quantities of substances it is advantageous to ex-clude shortwave light as far as possible when carrying out the reac- ~`~
tions, i.e. to work under yellow light, for example.
Examples of components which, when homopolymerized or co-polymerized, lead to light-cross-linkable polymers in accordance with the invention are:

. : .
.. , ,.' :~' ' .

esters of polymerizable carboxylic acld with 2-pyridones carrying a hydroxy group, in particular:
1- (acryloyloxyethyl) -pyridone- (2), ~;
1- (methacryloyloxycthyl)-pyridone- (2), 3-methyl-1-(methacryloyloxyethyl)-pyridone-(2), 6-methyl-1- (methacryloyloxyethyl)-pyridone- ~2),

4, 6-dlmethyl-1-(acryloyloxyethyl)-pyridone-(2~
4,6-dimethyl-1-(2-methacryloyloxypropyl)-pyridone-(2), ~ ~.. . .
3,4,6-trimethyl-5-(methaeryloyloxymethyl)-pyridone-(2), 1, 4, 6-trimethyl-3- (methacryloyloxymethyl)-pyridone- (2), 1, 4-dimethyl-6- (methacryloyloxymethyl)-pyridone- (2), ~ ' 4 - rnethyl-6 - (methacryloyloxymethyl) -pyridone- (2), 1,4-dimethyl-3,5-diehlor-6-(methaeryloyloxymethyl)-pyrldone-(2), and 4, 6-dimethyl-1- (a-ehloraeryloyloxyethyl)-pyridone- (2), amides of polymerizable earboxyllc acids with 2-pyridones carrying an ,.
amino group, e.g.~
4,6-dimethyl-1-(methacryloylamino)-pyridone-(2), ;;`;
4, 6-dimethyl-1- (aeryloylamino) -pyrldone- (2), ~ `
1,4,6-trimethyl-3-(methaeryloylamino)-pyridone-(2), 1,4,6-trimethyl-3-(methaeryloylaminomethyl)-pyridone-(23, ~ ~
6-methyl-3-(aeryloylamino)-pyridone-(2), ; ~, 6-methyl-5- (aeryloylamino)-pyridone- (2), - , 1,4-climethyl-6-(methaeryloylaminomethyl)pyridone-(2), and I-butyl-4,6-dimethyl-5-(methaeryloylamino)-pyridone-(2 2-pyridones carrying vinyl groups, e.
4,6-dimethyl-1-vinyl-pyridone-(2), 1,4-dimethyl-6-vinyl-pyridone-(2), and l-vinyl-pyridone- (2) .

_ 5 _ ,~ ' K-22~37 ~(~38537 : `
The abotre-namecl compounds can be polymerized, to provide photo-cross-~in~able poLymers, alone, or mixed wlth ~ach other or to-gethcr with o~her substituted ethylenes, e.g. wlth rnethyl-, ethyL-, butyl-, n-hexyl-, ethylhexyl-acrylate or -methacrylate, ~-methoxy-ethyl-, ~3-methoxy-~3-ethoxy-ethyl- or furfuryl-methacrylate, with derivatives of polymerizable carboxylic acids, for example those de-scribed in German Offenlegunysschrift No. 2,052,569, in particular acrylates or methacrylates of hydroxy group-containing trialkylphosphine oxides, the alkyl groups of which contain irom 1-~ carbon atoms, e.g.
dimethyl-(methacryloyloxymethyl)-phosphine oxide with acrylonitrile, acrylamide, maleic acid anhydride, vinyl acetate, vinyl pyridine, vinyl carbazole,or especially with vinyl aromatic substances such as styrene, a-methylstyrene, vinyl toluene or chlorostyrene.
esters of polymerizable carboxylic acids with unsaturatecl alco-hols, e.g. methallylacrylate and -methacrylate, allylmethacrylate, methy1pentenYl - or propargyl methacrylate also may be used in limited amounts in the copolymerization, and beneficially influence the proper-ties of the polymers.
It is also possible to carry out copolymerization wlth photo-active monomers oE other types, in particular polymerizable 2-pyrone compounds as described in German Ofienlegungsschrift Mo. 2,310,306, and products havlng special properties thus can be obtained. ;
A further method of producing the polymers of the invention, outlined under (b) above, comprises reacting polymers containing free carboxylic groups with 2-pyridones containing hydroxy or amino groups ~ -whereby there are obtained esters and amides, respectively. The esters and amides, of course, also can be produced by other known processes.
' ' ~ .. . .

1031~537 As polymers that contain free carboxylic groups there may be especially mentioned the homopolymers and copolymers oi acrylic acid and methacrylic acid or their derivatives, and copolymers of maleic acid anhydride, e.g. with ethylene or styrene. l~
Photo-cross-linkable polymers of the invention also may be obtained, as outlined in (b) above, by esterifying polyhydroxy com~
pounds of polymeric structure with 2-pyridones containing a carboxylic group. For this purpose the hydroxy groups do not need to be present in the free form; instead they may, for example, be esterified or aceta.lized, particularly with highly volatlle acids or aldehydes, which are driven off during the reactlon by the less volatile carboxylLc acid. . ``: . `
The carboxylic acids, oi course, also can be used ln the form of reac~
tive derivatives such as chlorides, anhydrides or esters with highly volatile alcohols such as methanol. Polymeric polyhydroxy compounds which may be used are, in partLcular, polyvinyl alcohol or cellulose ~ which may be partia.l.ly esterified or etherified~
- . Other suitable polyhydroxy compounds are, for exarnple, epoxide resins, e.g. condensation products of 2,2-bis-(p-hydroxy-phenyl)- `
,~
. propane with epichlorohydrin, condensatlon products of glycide and . .
polyfunctional phenols, as well as polyamides, polyacetals, poly- ~ ~
esters, polyurethnnes, or polyureas, each containing hydroxy groups. . ~ .
Polymers of simi.lar structure are also obtainable in a simple manner by the homopolymerization or copolymerization of the vinyl esters of i-t carboxyl group-containing 2-pyridones. .
Examples of 2-pyridones carrying carboxyl groups that can be used in the above-stated manner are~
l-carboxymethyl-pyridone-(2), `
l-carboxyethyl--pyridone-(2), : ~ .:

............. . - , .,.. - .. . .. . . .... . . . . ... .. ..

1038537 ~ ~
4,6-dimethyl-1-carboxymethyl-pyridone-(2), -- 4, 6-dimethyl~1-carboxypropyL-pyrldone- (2), -4, 6-dimethyl-1-carboxypentyl-pyridone-(2~, 1, 4, 6-trimethyl-3-carboxy-pyridone-(2), 4, 6-dimethyl-5-carboxy-pyridone- (2), 1, 4-dimethyl-6-carboxy-pyridone- (2), and . ;~
1, 3, 4, 6-tetramethyl-5-carboxymethyl-pyridone-- ~2) .
A further method of producing photo-cross-linkable polymers of the invention, outlined under (b) above, comprises reacting polym- . :
eric polyhydroxy compounds with 2-pyridones carrying aldehyde groups.
Suitable polyhydroxy compounds are, in particular, polyvinyl a.lcohol and cellulose. The hydroxy groups do not need to be present in free form for the purpose of the reaction; instead they may be complete~ly or partlally esterlfied or acetalized, particularly with highly volati.Le . , - . carboxy.lic acids or a.ldehydes. Examples of aldehydes which may be used for the purpose of aceta.lizing polyhydroxy compounds are~
1 ` ~' : ' ' 1- (formylmethy.l) -pyridone- (2), I .
4 , 6-dimethyl- 1 -formyl methyl -pyridone- (2 ), ~ . : -I ., 3, 4, 6 -trimethy.l- l -formy.l methy.l-pyridone- (2 ), 20 1,4,6-trimethy.1-3-formyl-pyridone-(2), 3, 4, 6-trimethyl-5-formyl-pyridone- (2), and ~ : .
1 ,4-dimethyl-6-formyl-pyridone-(2) . ` .
As regards those of the above-named compounds not already known, these can be readily produced from known compounds by known ~. .
methods. It i9 for example known from the literature that 2-pyrones can be converted into the corresponding 2-pyridones by reacting them .:
with ammonia or primary amines, 2-pyridones which carry hydrogen on . ::
the nitrogen atom may be alkylated at this point, for example, by reac-tion with halogenated carboxylic acids or their esters to obtain the ~ 1' 1~)38537 ~ ~
l-carboxyalkyl-pyridones or their esters, or with alkenyl halides to ~orm the l-alkenyl-pyridones-(2) which can be oxidized to give the formylalkyl-pyridones-(2), by known methods, e.g. by means of ozone. ;;~
;~
The formyl group may be introduced into the pyridone ring by the Vils-- ,~
meyer reaction, and the oxidation or reduction of the aldehydes is a .
method of obtaining the corresponding carboxylic acid or hydroxymethyl derivatives.
Aminopyridones can be produced, for example, by nitrating the 2-pyridones with subsequent reduction. j.
Isomer mixtures, such as can occur for example upon substitu- - . .. :~
1- ::: .
tion of the pyridone ring when the 3- and 5-positions are unoccupied are equal.ly suitab.le as the prlme isomers for use in preparing the polymers of the invention, 1.~
1;~ ' ~;: ' ' Depending upon their composition, the polymers of the invention ` ;: .:

are readily so.luble in one or more of the common organic solvents, for ;

example methanol, ethanol or acetone, which optionaliy may be in ad~

mixture with water, methylene chloride, chloroform, carbon tetra- i.
. . .
ch.loride, methyl glycol acetate, benzene, chlorobenzene, trichlor- ¦

:: ~ ethylene, cyclohexanone, butanone or dimethyl formamide, or they may be separated from inso.luble constituents by dissolution in one or more ` ~ ;

of these solvents. In the form af solutions i.n one or more of these sol~
: ~ .
vents, they may be applied as thin layers to, .for example, meta.l.lic or p.lastic carriers, and after removal of the solvent there remains a layer of polymer which adheres firmly to the carrier. When the layer is image~
. wise exposed through an original, using light sources which are nor-mally employed in reproduction methods and which contain a consider~
able amount of Light having a 300-700 nm wavelength, the exposed . ;.- `~ -areas of the layer are cross-linked and are thus rendered insoluble, _ 9 _ ,~

, , , :

~-2287 -~

whereas the unexposed areas can be removed with the ald of a solvent ;~
so that a negative copy of the original Is obtained.
Although the polymers of the invention have an inherently high photosensitivity, it is possible and on occasion advantageous to in~
crease their sensitivity still further by the addition of sensitlzers.
Particularly suitable sensitizers, which are generally used in quanti~
ties of 0 .1 to 15% by weight, preferably I - 1û% by weight, based on the polymer, are carbonyl compounds such as acetophenone or 4,4'~
bis-dimethylamino-benzophenone. ~;
. ~
The following are some examples of the application of the poly- ~ ~
;
mers of the in~ention, which may be in the form of a layer thereof on any suitable carrier, as mentioned above, e~g. of metal (one or several metals), paper, plastlc material, glass or ceramic material, or in the form of a self-supporting film, e.g. a film between two plastic protec-.
tive films, or of a copying varnish, i.e. dissolved in a suitable sol-. ~ ., - -vent~

The production of printing plates for planographic printing and ~ . " " ; ~
offset printing, screen printing, relief printing and intaglio printing, and In particular for use as photoresists for the photo-mechanical pro-'.:, . .
- 20 duction of resists, in particular electro-resists or etching resists, e.g. for the manufacture of printed circuit boards, and for the etching .
of shaped parts, and the manufacture of graduated scales, face plates, ~ ;
etc. ~
The polymers, however, also may be used in a form suitable ` ~;
for producing individual copies, the copying layer being tinted and the unexposed areas being removed after image-wise exposure, or an un~
colored layer being developed after image-wise exposure, the picture zones subsequently being tinted with a suitable colorant solution.

., .. . ~,...... .. .. , . ; , .

~e~3~ 7 ~ ~
For the purpose of ;produc~icopies it is also possible to make use of the differing meLting or softening behavlor of unexposed and exposed areas of the layer, e.g. by transferring unexposed and optionally tinted portions of the layer to receptor sheets, or by powder~
ing the heated layer with pigments which preferentially adhere to the -unexposed areas of the coating. -It is possible to combine the polymers of the invention with known copying compositions e.g. with compositlons which contain or consist of diazo compounds, azido compounds or other photo-cross-linkable or photo-polymerizable systems.
It is possible - and hereln resides a considerable advantage over earlier methods of producing photo-reactive polymers - to obtain ~ ;
polymers of the Invention by hitherto tried and trusted polymerization ~
processes. By a suitable choice of comonomers and by carrying out ~ `
suitable tests relating to temperature, solvent, amount and nature of the catalyst, chain~breakers, etc. used in the process for production of the polymers, it is possible to obtain polymers havlng practically any required molecular weight wlthin wide limits and thus additionally to influence the properties of the polymer, particularly its physical properties. In particular, however, the large number of comonomers which may be used offers practically unlimited possibilitles of influena~
ing the properties of the products in the desired manner. In particular, ; by~the introduction, by polymerization, of unsaturated acids~such as acrylic acid, methacrylic aaid, crotonia acid, vinyl phosphonic acid or vinyl sulfonic aaid, or for example, of dimethyl-methacryloyloxymethyl-phosphine oxide, lt is also possible to modify at will the adherence, especially to metallic substrates, and the solubility of the poLymers.
` .
Thus ior example, the copolymer of 30 mole %, 4,6~-dimethyl~
(2'-methaaryloyloxy-ethyl)-pyridone-(2) (I) and 70 mole % dimethyl- ;~
~ :

...... . . . . . . . .. . . . . .

~ ~ K-2287 ~ ~
103iZ3537 methacryloyloxymethyl-phosphine oxide exhibits excellent adhesion to -: an electrolytically roughened aluminum foil and Lt dissolves readlly in , water. In contrast to this, corresponding copolymers of I with, for -;
example, viny.l to.luene or butyl methacrylate are soluble only In purely organic solvents such as methylene chloride or chloroform.
Polymers which have a sufficient number of free acid or amino groups in the form of their salts with inorganic or organic bases or inorganic or organic acids are sufficiently solub.le in water to enable processing to be carried out without the use of organic solvents. .
.
10 Copying coatings which contain polymers with free acid groups there~
fore can be deve.loped with aqueous-alkaline so.lutions, and copying layers which contain po.lymers with amino groups can be developed with ; ~:
aqueous acidlc solutions, small quantities of water-mlsclble organIc . .
so.lvents optlonally being added. ;
The fol.lowing Examples further i.l.lustrate the invention. Unless .
otherwise stated, the qu.antity ratios and percentages are in unlts of welght.
` . . The production and testing of l:he photosensitive polymers were .. : -~ carried out in rooms illuminated with ye.l.low light. .

2Q Polymerlzation was carried out generally in the manner set .,. ;:
forth below:
A nitrogen-flushed solution of the monomers and a small quan~
tity of a radical initiator, e.g. azido-isobutyric acid nitrile (AIBN), .
.lauroyi peroxide or benzoyl peroxide, in a suitable solvent, e.g.
butanone, was heated to a po.lymerization temperature, dependent upon the initlator and generally Iying between 40 and 100C, and prefer~
ably between 60 and 80C, until the required degree of polymeriza- .
tion was reached, the mixture being stirred during heating. ;:

.

- 12- .

~L~38~37 : ~ :
When the polymerization was terminated, the reaction mixture was `~
diluted with a suitable solvent, e.g. acetone, and was freed by filtration of any particles of gel present, by the application of pressure if necessary, and was stirred into a suitable precipitating agent, e.g. etherlpetroleum ;: ' :. .
ether (1/l) to induce the polymer to settle. After fiLltration, the polymer was dried at an elevated temperature, preferably between 40 and 60C, in a vacuum, and was then ground. .

1 % The absorption maxima (~ values) and the extinction values `~
(E 1 cm) were measured in methylene chloride, except where otherwise stated.
In the Examples, E stands for E 1 cm, and connotes the optical density of a solution of 1 g of polymer in 100 ml of solution for a thickness of coating ` ` ~ -of 1 cm. RSV means the reduced viscosity ~red ~ spc. (dl/g) in a 1% ~`-,;
c solution at 25C. Unless otherwise stated, the RSV values were determined in .. ; ~. .
chloroform.
Exa~ple 1 4,6-dimethyl-1-(2'-hydroxyethyl)-pyridone-(2) was con~erted with ;
methacrylic acid chloride and by known methods into 4,6-dimethyl-1-(2'~
methacryloylox~-e~hyl)-pyridone-(2) (I), melting point 61.5 - 63.5 C.
7.05 g of I and 3.6 g of vinyl toluene (II) (molar ratio I~
~.:,. , :
1:1~ were polymerized, with 18 mg of (azodiisobutyronitril) AIBN as an ~ ~ ;
initiator, in 12 ml of butanone for 5 1/2 hours at 80C in nitrogen. After cooling, the mixture wa~ diluted with 100 ml of acetone, and the solution ;~
was filtered and stirred into 1 liter of petroleum ether (boiling point range 60 - 80C). After drying, there were obtained 6.1 g of a white powder ;
which was readily soluble in, for example, acetone, butanone, methylene chloride or chloroform.
~ max =310 nm; E =159 RSV = 0.41 dl/g.

' ~ .

- 13 - :~ ~

'~ , ~3~S3'7 The above-described polymer was applied to eLectrolyticaLly roughened aluminum from a solution in dimethyl formamLde together wlth 10% by weight of a sensitizer.
After drying for 5 minutes at 80C, a uniform film, containing 4 g of polymer per m, was obtained.
The film was exposed for 2 minutes through a 21-stage gray `
wedge (density range 0.05 - 3.05, density lncrement 0.15) at a lamp distance of 5 7 cm in a strlp-illumination apparatus which contained `
four Philips lurninescent Lamps, type TL/AK 40 W/05, disposed over an area of Z0 x 60 cm; the film was then developed by immersion for 1 minute in butanone, was tinted with a 1% solution of fat-soluble black EIB (C.I. 26150) in butanone to render the image easler to see, and the ~
excess colorant was washed off with lsopropanol. ~ ~ `
Sensitizer ~FulLy copied wedge~gs@~ ~ -~- none 6 `
Michler's ketone 13 Acetophenone 8 Example 2 `
2.4 g of 4,6-dimethyl-1-(2'-methacryloyloxy-ethyl)-pyridone- `~ ` ~
(2) (I) and 15.3 g of n-hexylmethacrylate (III) (molarratloI:III = 1:9) ;~ `
were polymerized by means of 30 mg of AIBN in 20 ml of butanone for J~ ~' ~, ' ` `'

5 1/2 hours at 80 C in nitrogen. After cooling, the material was ; ~
` ~ ~ . : :
diluted with 140 ml of acetone and 40 ml of methanol, and was pressure-filtered; the pQlymer was precipitated by stirring lnto 1500 ml of metha~
i.., ::::
nol. After drying, there were obtained 9.4 g of a white polymer which was readily soluble in xylene, acetone, butanone, methylene chloride or ~ ~
chloroform-. ~ -~,max = 310 nm; E = 35.4 ~; RSV = 0 . 44 dl/g .

,`.'` ',' '~

~2~
The polymer (4 g/m ) together wlth 10% by weight of Mlchler's ketone was deposited from chloroform onto electrolytically roughened ~ ~`
aluminum. After 10 minutes' exposure as in Example 1, developing in ~-acetone and tinting with fat-soluble black HB, 4 - 5 gray wedge stages could be detected.
- Example 3 -- 7.05 g of 4,6-dimethyl-1-(2'-methacryloyloxy-ethyl)-pyridone- ~-- (2) (I) and 3.15 g of 4-vLnyl pyridine (IV) (molar ratlo I:IV = 1.1j were polymerized by means of 18 mg of AIBN in 12 ml of butanone for 5 1/2 hours at 80C in nitrogen. After having been diluted with 120 ml of -chloroform and pressure-filtered, the material was stirred lnto 1 liter of ether/petroleum ether (1:1), and the preclpitated slightly reddish polymer was dried. 6.8 g were obtalned. The polymer was soluble in, for example, 2 N HCI, methanol, methylene chlorlde or chloroform.
~max = 310 nm; E = 154.5 RSV =0.4 dl/g.
A film of the polymer (4 g/m2) with 10% by weight of Michler's ketone was exposed for 2 minutes as in Example 1 on a foil of electro-l~tically roughened aluminum. After developlng either with methanol ` -- 20 or 2 N HCl, 9 gray wedge stages could be detected and these could be readily tinted with fat-soluble black HB frorn isopropanol/methylene chloride (4 ~ s Example 4 -3.5 g of 4,6-dimethyl-1-(2'-methacryloyloxy-ethyl)-pyridone~
(2) ~I) and 6.7 g of dimethyl-methacryloyloxymethyl-phosphinic oxide ~V~ (molar ratio I:V = 3:7) were polymerized by means of 15 mg of AIBN
in 10 ml of butanone for 5 1/2 hours at B0C In nitrogen. After dis-solving wlth 120 ml methanol and pressure-filtration, the mLxture was - .
- 1 5 ~

K-ZZ87 i~
~)385~7 stirred into 1 liter of ether/petroleum ether (boilLng point ranye 30 80 C; 1:1), and the precLpitated polymer was dried. 10.1 g were ;
obtained.
The polymer was readily soluble in water, methanol, ethylene ;
glycol methyl ether acetate, dimethyl formamide, methylene chlorlde or chloroform.
~ max = 301 nm; E = 70.2 shoulder = 308 nm; RSV = 0. 97 dl/g.
The film of the polymer (2 g/m2) with 10% by welght of Michler's ketone on electrolytically roughened aluminum was exposed for 5 min~
... . ..
utes in the manner described in Example 1, and was developed with ~ ;
.,., :.~: : , water. After tinting with fat-soluble black HB, 11 gray wedge stages . .. ..
.. ..
could be detected. ~ ~
v Example 5 amino-4!6-dimethyl-pyrldone-(2) ~VV. Ried et al, Chem. Ber.
90 (1957), 2841) was converted by~known methods into l-methacryloyl~
amino-4, 6-dimethyl-pyridone- (2) (VI), melting point 142 - 143 C,;~
~by reacting it with methacrylic acld chloride.
7.8 g of VI and 6 . 3 g of n-hexyl methacrylate (III) (molar ratio VI:III = 1:1) were polymerlzed by means of 9 mg of AIBN in 65 ml of benzene for 7 hours at 80 C in nitrogen. After the material had been diluted with 200 ml of chloroform and pressure-filtered, it was stirred into 1.5 Iiters of ether/petroleum ether (3:1j, and the precipitated polymer was dried. 9.5 g of white flakes were obtainèd. The polymer ;;~j~, -,. ~
- was readily soluble in, for example, chloroform, methylene chloride ;5 ~ ~
.~. .
or trichlorethylene.

~max = 303 nm; E = 196 ~; RSV = 0.46 dl/g.
: , . ~;
, - 1 6 - ; ~
-. . . . . . . . . . . . . . . . . . . . . , . , ~ ~. . . . . . . . . . . . . . . : . :

31 ~38537 ~ r ~
A film of the polymer (2 g/m~) with 10% by weight of Michler's ;
ketone, on electrolytlcally roughened aluminum, was exposed for 30 seconds as in Example 1 through a metal original. After developing with trichlorethylene, drylng in warm air, hydrophllizlng wlth a 1%
phosphoric acid solution, drying and tinting with fat-soluble black HB, ;
a negative copy of the metal original was readily observable.
.. .. .
Example 6 3-methacryloylamlno-1,4,6-trimethyl-pyridone-(2) (VII), melt~
ing point 148 - 151 C was produced from 3-amlno-1,4,6-trimethyl~
pyrldone-(2) by means of methacryllc acld chloride, using known method s .
2 . 2 g of VII and 1. 2 g of vinyl toluene (II) (molar ratio VII~
1:1) were polymerlzed by means of 7 mg of AIBN ln 7 ml of butanone for

6 1/4 hours at 80 C ln nltrogen. After dilution with 6~ ml of chloro~
- form and pressure-filtering, the polymer was caused to precipitate by belng stirred into 1.6 liters of ether/petroleum ether (3:1). 1.6 g were obtained.
~max = 314 nm; E = 279 PSV = 0.22 dl/g.
, , A film of the polymer (2 g/m2) and 10% by weight of Michler's ` `
.~
ketone was exposed for 2 minutes in the manner descrlbed in ExampLe 1. After developing with methylene chloride and tinting with a 1% fat~
soluble black HB solution in isopropanol/methylene chlorLde (4:1), 4 gray wedge stages could be detected.
Example 7 1.1 g of 3-methacryloylamino-1,4,6-trimethyl-pyridone-(2) ;
: . :
III) and 6.4 g of n-butylmethacrylate (VIII) (molar ratio VII:t)lII = 1:9) were polymerized by m~ans of 6 mg of AIBN in 5 ml of butanone for ~, , K-2287 ~-6 1/2 hours at 80C in nitrogcn. After dilution with 60 ml of chloro~
form and pressure-filtration, the mlxture was stirred into 1.5 liters of ~ '.
methanol. After the addition of a little NaCI, the polymer precipitated . '. ...
in lumps from the milky clouded liquid. 4.6 g were obtained.
The polymer was readily soluble in dioxane, methylene chLor.ide, ~ . . ~ ' . ' ' chloroform and xylene.
~max = 315 nm; E = 61.7 . :
RSV = 0.89 dl/g. i.
A strong ester band occurred at 1720 cm in the infra-red spec- .
trum of the polymer in methylene chloride.
A film of the polymer (2 g/m2) with 10% by weight of Michler's ':
'- '' ketone was exposed, as in Example 1, for 5 minutes on a foll of electro~
.IytLcally roughened aluminum, developed with dimethyl formamlde and ' :;:;

tinted with fat-so.luble black HB from isopropanol/methylene ch.loride (4:1). Eight gray wedge stages could be seen.
- -.
ExampLe 8 ' "
. 5.1 g of 4,6-dimethyl-1-(2'-hydroxy-ethyl)-pyridone-(2? and 6.1 g of a 1:1 styrene:maleinic acid anhydride mixed polymer ~RSV =. ..
0.64 dl/g, 25C, 1% in acetone) were stirred in 70 ml of absolute '; "
pyrldine for 7 hours at reflux temperature.
After cooling to 25 C, the c~iear polymer solution was stirred'~
into a mixture of 200 ml of glacial acetic acid and 800 ml of water, the '- .
'polymer precipitating. After dryLng, 8.7 g of a light-brown polymer . .: ' . - ;
were obtained.
The polymer dis solved readily in dimethyl sulfoxide , dimethyl '':
formamide or diacetone a.lcohol.
~max (DMF) = 312 nm; E - 93.7 - ' ' :
RSV = 0.76 dl/g (25C, 1% in DMF). ~' ~ .

:: ..... .. : . . . .

~6338537 The poLymer (2 g/m2) together with 10% by weight of Michler's : , ketone was deposited from DMF on e!ectrolytically roughened alumi-num, and the film was dried for 5 minutes at 80 C. After 5 minutes' exposure as in Example 1, developing with DMF and tinting with a 10%
aqueous methylene blue solution, 5 gray wedge stages became visible.

.~
Example 9 4,6-dimethyl-1- (2 ' -acetoxy-ethyl)~pyridone- (2) was obtained by known methods from 4,6-dimethyl-1-(2'-hydroxyethyl)-pyridone-(2), and its pyrolysis in a vertical tube (nitrogen stream) at 430 C
~.
gave a 95% yield of 4,6-dimethyl-1-vlnyl-pyrldone-(2), melting point 44- 46C.
. : : .
CgH11NO - calculated: C 72.45%; H 7.43%; N 9.39%
determLned: C 72.6%; H 7.7%; N 9.2% ;~
3.72 g (25 m/mole) of 4,6-dlmethyl-1-vlnyl-pyridone-(2), 5.9 - g (25 mjmole) of 1-(2'-methacryLoyloxyethyl)-pyridone-(2) and 5.g g (50 m/mole) of vinyl toluene were polymerized with 10 mg of AIBN as an initiator in 18 ml o butanone for 6 hours at 80 C in the same way as - i .
in Example 1, and the resultant materlal was recovered . After drying, ~ ~
:~ . ' , ,:: :
12.9 g of a white powder were obtained, and this powder was readily ~.: .
soluble in, for example, butanone, methylene chlorlde or chloroiorm.

~max = 310 nm; E = 170 RSV = 0.92 dl/g. ;~

- After exposure, a film of the polymer on the carrier as used in Example 1 was insoluble over the exposed areas.
~ . . .
It wlll be obvious to those skilled Ln the art that many modifi-cations may be made within the scope of the present invention without -~: ~
departing from the spirit thereof, and the invention includes all such modifications.
, :` :
. ~' ' , . ,

Claims (17)

WHAT IS CLAIMED IS:

1. A photo-cross-linkable polymer containing units each having a 2-pyridone side group.

2. A polymer as claimed in claim 1 which is a polyester of a polym-eric polyhydroxy compound with a 2-pyridone compound containing a carboxyl group.

3. A polymer as claimed in claim 1 which is a polyacetal of a polymeric polyhydroxy compound with a 2-pyridone compound contain-ing an aldehyde group.

4. A polymer as claimed in claim 1 which comprises from about 5 to 100 mole % of polymerized vinyl or vinylidene units each of which is linked to the radical of a 2-pyridone compound through a direct covalent bond, an ester group, an amide group or an acetal group, and from about 95 to 0 mole % of comonomer units.

5. A polymer as claimed in claim 4 which comprises from 10 to 90 mole % of said vinyl or vinylidene units and from 90 to 10 mole % of comonomer units.

6. A polymer as claimed in claim 4 wherein the comonomer units are units of ethylene, vinyl esters, acrylic or methacrylic esters, -amides or -nitriles, maleic acid anhydride or vinyl heterocyclic or vinyl aromatic compounds which optionally contain a second polymeriz-able group.

7. A polymer as claimed in claim 6 which is a copolymer of an alkyl acrylate or alkyl methacrylate with an acrylate or methacrylate of a 2-pyridone compound containing a hydroxy group.

8. A polymer as claimed in claim 1 in which the units having the 2-pyridone side groups have the general formula:

wherein:
R1, R2, R3, R4 and R5, which may be the same or different, each represents hydrogen, halogen, or an alkyl group with from 1 to 4 carbon atoms, A represents a direct covalent bond or a -CONH-, -COO-, -O-CHOH- or group wherein each oxygen atom of the last-named group is linked to a unit of the basic chain, B represents an alkylene group having from 1 to 4 carbon atoms, and n is 0 or 1.

9. A polymer as claimed in claim 8 wherein said alkyl group is a methyl group.

10. A polymer as claimed in claim 8 wherein said halogen is chlorine.

11. A polymer as claimed in claim 8 wherein said alkylene group has 1 or 2 carbon atoms.

12. A polymer as claimed in claim 8 which is a copolymer of a vinyl compound and a vinyl ester of a 2-pyridone compound containing a carboxyl group.

13. A photosensitive copying material which includes a polymer as claimed in claim 1.

14. A copying material as claimed in claim 13 which is in the form of a self-supporting layer of said polymer.

15. A copying material as claimed in claim 14 wherein said layer additionally contains a sensitizer.

16. A copying material as claimed in claim 13 comprising a carrier and, on the surface of the carrier, a photosensitive layer which con-tains said polymer.

17. A copying material as claimed in claim 16 wherein said layer additionally contains a sensitizer.