DE1447582B2 - Photographic recording material - Google Patents

Description

-C-CH ₂ -

CO
HNX

is constructed in which R _{1 is} a hydrogen atom or a methyl group and X is the groups

-CH ₂ -OR ₂ or -CH ₂ -O-CO-R ₂

means in which R _{2 is} an alkyl radical.
The polymers used according to the invention can either be homopolymers of the monomers on which the above general formula is based, or copolymers of different ones

above general formula underlying monomers or with other comonomers, in particular be with vinyl monomers. For a copolymerization, methacrylic acid or are particularly suitable Acrylic acid or its derivatives such as acrylamide and methacrylamide or their N-alkylated derivatives, also acrylic or methacrylic acid esters, preferably those with short-chain aliphatic alcohols, especially methyl ester, or acrylonitrile. Other copolymerizable ones can also be used for the copolymerization Monomers such as ethylene, vinyl acetate or vinyl ether, especially those whose aliphatic ether grouping contains up to 4 carbon atoms can be used.

When producing such polymers, it is only necessary to ensure that the resulting Products are water-soluble and gelatin-compatible and that they do not have a harmful effect on the photographic Exercise properties of the photosensitive layers. Their effectiveness is based on that Content of the units of the above general formula justifies them in the specified concentration should contain.

The polymeric products to be used according to the invention preferably have a molecular weight in that Range between 50,000 and 100,000. The molecular weight is of secondary importance. Of the The most favorable molecular weight range can be determined by a few experiments.

The polymers according to the invention have an excellent opacity-increasing effect, so that even the addition of relatively small amounts produces clear effects. You also own the surprising one Property that they suppress the haze and partially increase the sensitivity. It is particularly noteworthy that the anti-fogging effect even under extreme conditions, for example, after prolonged storage in a heating cabinet at 60 ° C, can be determined.

The polymers to be used in the manner according to the invention can be prepared by known processes getting produced. Useful methods are, for example, in the following publication “The makromolekulare Chemie ", Vol. 57 (1962), pp. 27 to 51, described.

The production of a homopolymer and a copolymer is described in detail below:

Polymethacrylamide N-methylol methyl ether
Methacrylic acid amide-N-methylol-methyl ether

CH ₃
H ₂ C = C-CO-NH-CH ₂ -OCH ₃

55

In 7.51 carbon tetrachloride gradually 48 g at 40 ° C of powdery sodium methylate, after adding 6 g of hydroquinone 300 g of p-formaldehyde and 636 g of finely powdered methacrylamide (105 to 106 ⁰ C mp.) Was added with good stirring, so that after alkaline reaction prevails. The mixture is then heated to 50 to 55 ° C. for 1 hour, the methacrylamide gradually disappearing and the methylol compound being deposited as an oily layer on the carbon tetrachloride. The carbon tetrachloride is drawn off at 40 ° C. and the oil which has separated out (upper layer) is gradually poured, with stirring, into 3.6 l of methanol into which 48 g of HCl gas have previously been introduced. The entry takes place with slight self-heating, and after completion of the entry the solution still has a pH of about 2. It is allowed to react for 1 hour at 40 ° C. and the hydrochloric acid still present is now neutralized by adding 150 g of anhydrous, finely powdered soda. The mixture is then stirred until the solution has an alkaline reaction, the precipitated common salt and the soda still present are filtered off and the methanol is evaporated in vacuo. The remaining oil boils at 86 ° C / 0.8 mm. Yield: 781 g = 81% of theory.

Polymerization

830 g of benzene are placed in a three-necked flask equipped with a thermometer, stirrer and reflux condenser and submitted 170 g of the above monomer. After displacing the air with nitrogen, 0.85 g Azodiisobutyric acid dinitrile was added with stirring and the mixture was heated to 70.degree.

The polymerization takes place in 5 to 6 hours at 70 ° C., the polymer being a white powder separates.

After cooling, 100 g of acetone are added and the mixture is filtered off with suction.

After drying at 50 ° C. in vacuo, 156 g of a white powder with a K value of 38 to 40 are obtained obtained (92% of theory).

Copolymers of N-methylol methacrylamide

The copolymerization is carried out as described for the above polymerization, but is on Instead of 830 g of benzene, a mixture of 415 g of benzene and 415 g of ethyl acetate was used.

Yield: copolymer with acrylamide (1: 1) 94% K value: 63.5; Copolymer with methacrylamide (1: 1) 93% K value: 31.8 (according to Fikentscher, "Cellulosechemie", Vol. 13, p. 58 (1932).

The polymers according to the invention can be used in the light-sensitive silver halide emulsion layers or any auxiliary layers, such as intermediate or protective layers, can be added. It is not there critical at which stage of the emulsion production or the production of the casting solutions for the layers the polymers are added. They are used as aqueous solutions of 10 to 30 percent by weight of the polymer included. The colorless polymer powders are generally warm Easily soluble in water from 30 to 50 ° C.

The polymers according to the invention are added to the layers in amounts of preferably 10 to 50 g added per mole of silver halide. When used in emulsion layers, 5 to 50 percent by weight the gelatin to be replaced. The most favorable application concentrations vary depending on the product on the desired effect, the silver content of the emulsion and the type of silver halides used. The optimal application concentration can be generally known through a few comparative tests Way to be determined.

Gelatin is preferably used as a binder for the layers, which is completely or partially through other water-permeable film-forming colloids such as alginic acid and its derivatives can be replaced, z. B. salts or esters, also polyvinylpyrrolidones, starch, carboxymethyl cellulose.

5 6

_. Ii thick on a transparent base made of cellulose

e ι s ρ ι e acetate potted and dried.

A silver bromide emulsion containing 90 g of silver halo by increasing the solids content

genid per liter of emulsion, the 2 mole percent silver - the latter two samples less silver halide

Contains iodide, is added with the usual additives, such as 5 per square meter of film. After exposure after the

Wetting agent, for example saponin (30 ml of a 7.5 ge method by van B ri e s e η behind a gray wedge

weight percent aqueous solution per kilogram of the sequence / ~ 2 ~ the 3 samples are 5 minutes

the emulsion) and stabilizer, e.g. B. of the long at 20 ° C type in a developer of the following

Azaindolizins, especially 5-methyl-7-hydroxy- composition developed:

2,3,4-triazaindolizine (250 mg per kilogram of emul- 10 ,,,, ·,, -, _e

sion), and a hardener, for example p-methylaminophenol 3.5 g

one of the described in DT-PS 8 72 153, sodium sulfate sicc 60 g

offset and divided into several samples. The one hydroquinone y g

Sample serves as a comparison, another will be per 7? Y ^S1C £ ' "·"*' τ f

Liter 50 ml, a third 100 ml a 20 weight. ₅ f ~ f ™ "™ ^bromide · ■ · ■ · ··. · ^ ³ p

percent aqueous solution of polymethacrylic with water on 11 aufTullen.

amide-N-methylol-methyl ether added. The results of the experiments are shown as follows

All 3 emulsion samples are made with the same casting Table 1:

Table 1

sample additive sensitivity 7th veil Silver application D _max Silver application (° DIN) (g / m ² ) (1-t = const.) 2.5
2.9. ··
/ 3.0 A.
B.
C. 50 ml
100 ml Type
± 0
+ 3.5
4.0
3.6 0.05
0.04
0.05 12.6
11.3
10.5 3.1
3.25
3.15

The photographic properties of the same emulsions ung at 6O ⁰ C are shown in the following Table 2:

after a three-day heating cabinet test

Table 2

Sample sensitivity y

C DIN)

veil

A. Type 2.7 0.16 B. ± 0 2.9 0.13 C. + 1 ° 2.9 0.14 Table 3

50 ml
100 ml

33-

40

Example 2

A copolymer of polymethacrylamide-N-methylol methyl ether with polymethacrylamide in a molar ratio of 1: 1 is also used in the amounts of 50 and 100 ml of a 20 weight percent solution of a similar emulsion as in Example 1 indicated, added. It is also processed as described there.

Table 3 below shows that here too, with decreasing silver application, gamma and sensitivity are essentially preserved.

sample additive sensitivity y veil Silver application U-t = const.) D _max ■ 10 (° DIN) (g / m ² ) Silver application

Type

+0.5

+0.2

3.0 0.10 2.9 0.08 2.5 0.28

12.7
11.2
10.3

3.0
2.9

2.8

2.4
2.6

2.7

Example 3

50 ml of a 20 percent strength by weight solution are added to a silver halide emulsion according to Example 1 of polymethacrylamide - N - methylol - methyl ether and pour the emulsion as indicated. The light sensitive The emulsion layer is covered with a protective layer that contains an accelerator from Contains type of polyethylene oxide (sample G). In another sample, the emulsion layer is applied before the Potting also a mercury stabilizer

(Derivative of mercury thiazole chloride) added (sample H). The result of table 4 can be seen: that when the general sensitivity is increased, the same opacity-increasing effect can be observed and, above all, hardly any increase in haze ■ what else is there when using this Substances is common in highly sensitive emulsions.

Table 4 additive 7th sensitivity y 14th 47 582 Silver application 8th D ^ ΊΟ sample Γ DIN) veil (g / m ² ) Silver application 50 ml
50 ml Type
+ 1.3
+0.3 3.5
3.1
3.5 12.6
11.2
11.3 (/ ■ / = const.) 2.5
2.8
2.8 A.
G
H 0.05
0.07
0.03 OJ OJ OJ
K) - -
Ul

If this material is additionally stabilized with N-methyl methacrylamide and 25 mol percent acrylic with the mercury stabilizer, then acidic, according to BE-PS 6 20 515, a very low haze is obtained as opacity with good sensitivity. increasing substance added. The material used in these examples is intended to make it clear that it is also processed in the same way.
Combination with accelerators and other stabilizers. It can be seen from the following table that the lisatoren this substance retains its advantages. photographic properties to a great extent. . to be worsened. Compared to the Standardis e 1 s ρ 1 e 1 4 sample A, the blackening was about the same, so that a

A silver halide emulsion according to Example 1 20 has an opacity-increasing effect,

As a comparison, 50 ml of a 20 percent by weight - a practical application due to the high

However, a solution of a copolymer of 75 mol percent haze is not possible.

Table 5
Sample addition

sensitivity γ veil Silver application (It = const.) Silver application Γ DIN) (g / m ² ) 3.1
3.0 2.5 '
2.7 Type
-3 3.5
2.9 0.05
0.70 12.5
11.3

A -

K 50 ml

Example 5

A silver chlorobromide emulsion with 107 g of silver per kilogram of emulsion, of which 1 mole percent as Silver iodide, is used as a basis for the following comparison. Different parts of the emulsion are per Kilograms of increasing amounts of the polymers to be compared in the form of a 20% strength aqueous solution added, as can be seen from the table. After exposure and development, as described in Example 1, are achieved the following results:

Table 6

sample additive Sensation y veil Silver application D _max Silver application opportunity (° DIN) (g / m ² ) 2.05 A. Type 1.00 0.19 9.1 1.85 2.35 B. 50 ml polymer A ± 0 1.05 0.19 8.3 1.95 2.45 C. 75 ml polymer A ± 0 1.00 0.20 .8.2 2.00 2.50 D. 100 ml polymer A ± 0 1.00 0.20 8.1 2.15 2.10 E. 50 ml polymer B ± 0 0.95 0.18 8.5 1.80 2.15 F. 75 ml polymer B ± 0 0.95 0.17 8.4 1.80

G 100 ml polymer B ± 0 1.00 0.18 8.6 1.90 2.20

Polymer A = polymethacrylamide-N-methylol-methyl ether according to the present invention.

Polymer B = copolymer of N- (1,3-dihydroxy-2-methyl) isopropyl methacrylamide and methacrylamide according to Example 7 of DT-AS 1049 100.

Claims (2)

Patent claims: 1. Photographic recording material having at least one silver halide emulsion layer with a content of a water-soluble polymer whose monomeric units differ from an N-alkylol methacrylamide or N-alkylol acrylamide, thereby characterized in that it is a water-soluble polymer in Amounts of 5 to 140 g per mole of silver halide, a co- or homopolymer, which to 15 to 100 mol percent of units of the general formula R ₁
-C-CH, - CO HNX is constructed in which R _{1 is} a hydrogen atom or a methyl group and X is the groups -CH ₂ -OR ₂ or -CH ₂ -O-CO-R ₂ means in which R _{2 is} an alkyl radical. 2. Recording material according to claim 1, characterized by the content of a homopolymer, built up from units of the methyl ether of N-methylol-methacrylamide, or one Copolymer, built up from units of the methyl ether of N-methylol methacrylamide and Acrylic or methacrylamide. The invention relates to a photographic recording material having at least one silver halide emulsion layer with a content of a water-soluble polymer, its monomeric units derive from an N-alkylol methacrylamide or N-alkylol acrylamide. It is known that the opacity of photographic silver in the form of Silver images in processed photographic layers as they are exposed during development Silver halide emulsion layers are created by adding a wide variety of compounds. With the addition of the compounds, a higher density is achieved with the same silver halide concentration or a considerable amount of silver can be saved if only the same density is obtained shall be. In particular, polysaccharides and their derivatives were used for the present purpose used. However, the practical use of these compounds is limited, since they are a troublesome Cause fogging and also photographic layers containing these additives, tend to stick, especially when stored in damp conditions. There were also polyvinylpyrrolidone or N-alkylated polymethacrylamides are used for this purpose. However, these connections are also in hardly applicable in practice, since they also make use of the photographic properties of the layers Impair the formation of fog. There has been no shortage of attempts, the main disadvantage of the known Compounds that suppress fogging by adding fogging-preventing agents. the However, the results are unsatisfactory. Γη of DT-AS 10 49100 are mixed polymers described, derived from N-alkylol (meth) acrylamides. These copolymers are said to be used as gelatin substitutes be suitable for photographic materials, through a silver covering power-increasing effect nothing is known of the copolymers mentioned. In fact, it couldn't have had such an effect being found. "The DT-AS 11 61 759 can be seen that through suitable modification of polyacrylamide as a binder for silver halide emulsion that as an artificial product has advantages over the commonly used natural product gelatine having. These modified polyacrylamides can be used as peptizers in the precipitation of the Silver halide are used and affect the grain growth and crystal structure of the Silver halide in a similar way to gelatin, via one that increases the silver covering power The effect is not known. The invention is based on the object of specifying substances that improve the opacity of silver halide layers increase without impairing the other photographic properties at the same time. It has now been found that certain water-soluble copolymers or homopolymers of ethers or esters of N-methylol-methacrylamide or N-methylol-acrylamide are outstandingly suitable for this purpose. The other photographic properties are not impaired, in particular the fog is not increased.
The invention relates to a photographic recording material with at least one silver halide emulsion layer containing a water-soluble polymer whose monomeric units are derived from an N-alkylol methacrylamide or N-alkylol acrylamide, characterized in that it is used as a water-soluble polymer in amounts of 5 to 140 g per mole of silver halide, a co- or homopolymer containing 15 to 100 mole percent of units of the general formula