DD277343A1 - METHOD OF DISPERSING HYDROPHOBIC COMPONENTS - Google Patents

Abstract

For dispersing hydrophobic components for the production of gelatin-containing layers containing high-boiling organic solvents in disperse form and optionally photographically active substances (color couplers, antioxidants, additives, polymers, plasifikatoren), is used as dispersing a mixture of an anionic surfactant (alkyl sulfates, alkylbenzenesulfonates or Alkylnaphthalenesulfonates) and a polysiloxane-polyether copolymer of general structure I and / or II and / or III. The resulting dispersions are storage stable; they have a reduced coarse fraction of the dispersed particles in the range of 0.2 mm, whereby the transparency of the layers produced therewith is improved. Formulas I to III

Description

1 '> λ / Δ ^λ η / 2 ^ν' 1. Μ / 3 ^J '' 1.

v / orin P-. - (Cm ₀ ). - (0 ·;)., - (OP) ,, - Γ> _ο ^; .

c. .'J ,, _t

o: - -o -ZW _n - c :; _r or - -cc; - ci -i _p -

C-U

n; : 1 - before: '!. u ::; v,' oiGCi 'ZZ

η 5 - ?. ^v .Xj _t before :: ü _ü o'.vüic; e 10 - l ^r 0

y , A _r ₀

n " 'Hey ^1, vo r:;.. u jG'.vcieo ethyl !!

', 1 ^ = I; ct! Io:; y-, 3uto ;; y ~,;', c,] l: oxy- or Cyonc L "ho ;; · /

mean is used.

2. The method according to claim 1, characterized in that as anionic surfactant alkyl sulfates, alkylbenzenesulfonates or alkylnaphthalenesulfonates having a weight ratio of anionic surfactant to polysiloxane-polyether copolymers of 3: 1 to 1: 3 are used.

Field of application of the invention

The invention relates to a process for the preparation of oil-containing dispersions containing high-boiling organic solvents, optionally photographically active substances such as color couplers, antioxidants, additives, polymers or plasticizers and are used in silver halide or auxiliary layers.

-2- 27/343 j

Characteristic of the known technical solutions

In the production of modern silver halide materials, high boiling organic solvents are used in dispersed form in emulsion and auxiliary layers. The introduction of high-boiling solvents into hydrophilic colloids takes place with the addition of surface-active dispersing aids. The resulting dispersions have particle sizes between 0.15 and 0.4 μm.

In addition to the dispersion technology (rotor-stator principle, pressure atomization, spontaneous emulsification), the structure and concentration of the dispersing aid are of great importance for the quality of the dispersions. The surface-active substances used as dispersing agents must have a good dispersing effect and a high stabilizing power for the disperse phase. In addition, they must be photographically inactive and must not interfere with the coating process in the production of photographic materials.

As surfactants for din introduction of hydrophobic components in hydrophilic colloids alkyl sulfates or alkyl sulfonates (DE 2448597) are known. In addition, alkylbenzene and alkylnaphthalenesulfonate can be used for the dispersion of high-boiling organic solvents and oil-protected color coupler (US 2322027, US 2801170). DE 1942873 describes mixtures of ionic and nonionic wetting agents as dispersing aids for photographic components. Furthermore, polymeric surfactants based on maleic anhydride copolymers are known as surface-active substances for oil-protected hydrophobic substances (DE 2613005, DE 2361185).

However, the dispersion aids known hitherto, especially in the introduction of high-boiling organic solvents, have an undesired coarse fraction in the range of> 0.2 μm, which is detected by light microscopy

In addition, surfactants have insufficient stabilizing power for the disperse phase, so that it comes to exudation of the high-boiling organic solvents from the hydrophilic colloid layer and thus to change the degree of transparency of the layers.

Object of the invention

The object of the invention is an improved process for the dispersion of high-boiling organic solvents for photographic materials, which enables the production of stable dispersions with improved quality.

Explanation of the essence of the invention

The object of the invention is to find new dispersing aids for introducing high-boiling organic solvents, which may contain photographically active substances (color couplers, antioxidants, additives, polymers or plasticizers) in hydrophilic colloids, which lead to stable dispersions with a reduced coarse fraction and with which prevents exudation of high-boiling substances from hydrophilic colloid layers. According to the invention the object is achieved in that as a dispersing aid, a mixture of an anionic surfactant and a polysiloxane-polyether copolymer of the general structure

OK - (R ₁ -GiO) _m PE

(R ₁ - GiO ) _Λ - Gi R ₁ and / or

I ¹ ~ ^c H Π

«1 - ^Gi0 > n / 2

(II)

and / odcr

ivo r xn

iiO - (R ..- GiO } _Ω , _ζ

( R, - GiO) .._

^v 1 j ^y n / ~

( i - GiO), -,

PE

OE - - O CiI ₂ - CM ₀ -

CP- - O CM - CM ₀ CIL

OK) _{n / 2} - (R ₁ - G 10) _{ia / 3} -Si

PJ

(III)

- (0P) _y - R,

111

i-12, preferably 1-3

5-250, preferably 10-150

Λ - 50

4-50

R ₁ - alkyl, preferably r.efhyl

R ₀ = t'ethoxy, 3uto; y, acoxy or cyanoethoxy

mean is used.

According to the invention, a dispersing agent is used which contains, as polysiloxane-polyether copolymer, for example the following compounds:

connection

Ri

1 2 b 4 4 me butoxy 2 6 10 10 15 me butoxy 3 8th 20 10 10 me methoxy 4 10 30 15 15 me butoxy 5 6 100 40 40 me cyanoethoxy 6 8th 200 50 50 me methoxy 7 10 10 20 20 me methoxy 8th 12 20 10 10 me methoxy

As anionic surfactants are alkyl sulfates, for example

Na-dodecyl sulfate, alkylbenzenesulfonates, for example Na-nonylbenzenesulfonate or Alkylnaphthalinsuifonate, for example, Na-Triisobuthyl- or Na-Diisobiitylnaphthalinsulfonat used.

The surfactant mixtures according to the invention are used in a concentration of 5-15% by weight, preferably 7-10% by weight, based on the high-boiling solvent to be dispersed. The weight ratio of anionic surfactant to polysiloxane-polyether copolymers is 3: 1, preferably 2: 1 to 1: 2.

It is possible to add in the dispersion, the polysiloxane polymers of the aqueous and / or organic phase.

The polysiloxane-polyether copolymers used according to the invention are prepared by addition reactions of hydrosilanes with alkenyl ethers and polyethylene oxides, such as, for example, US Pat . 299112 and US 3955035.

Duα h the use of the surfactant mixtures according to the invention as Dispersierhiifsmittei for the introduction of hydrophobic

Components for photographic materials, it is possible to avoid the previously disturbing coarse fraction of the disperse phase in the range> 0.2μιτ \, whereby the transparency of the layers produced therewith is improved. The method is suitable for the preparation of (!) Dispersions for auxiliary layers or emulsion layers as well as for the incorporation of photographically active agents, such as, for example, antioxidants, color couplers, UV absorbers, sensitizers and the like.

embodiments

Example 1 (Comparative Example) 100 g of a yellow coupler of the structure

ο. ι-

-C-C-CiI

CC - UM ~ / V

\ ri co (c: u) _? -O-

r.i -

are dissolved in a mixture of 200ml ethyl acetate and 75ml dibutyl phthalate at 7O ⁰ C and contains sodium in 750 ml of 10% gelatin 10 g Na-Diisobutylnaphthalinsulfonat, at 65 ⁰ C 60min dispersed ohnellrührwerk by £. Subsequently, the ethyl acetate is removed by distillation.

50 ml of this dispersion are diluted with 25 ml of water and applied to a Cellulosetriacetatunterlage. After solidification and drying, the layer is assessed by light microscopy at a magnification of 200 times and the relative degree of transparency of the model layer against a gelatin layer on the spekol at 546 nm is determined.

It was determined a coarse fraction of 30Vol .-%. The relative transparency of the model film was 4.5%.

After 4 weeks of storage, the relative transparency of the model film was 8%.

Example 2

The procedure of Example 1 is repeated, using as dispersing a mixture of 5g Diisobuthylnaphthalinsulfonat and 5g of the compound 2 are used.

By light microscopy, no coarse fraction could be detected and the relative transparency of the model film was 0%. After 4 weeks of storage no deterioration of the model layer could be detected.

Example 3

100g of an antioxidant of the structure

O::

c ": 7.

C "

are dissolved in 300ml ethyl acetate and 200ml of tricresyl phosphate at 65 "C and washed at 62 ⁰ C by means of Schnellrührwerk in 2000ml 10% gelatin solution containing 7.5 g of Na-Nonylphenolsulfonat and 7.5 g of compound 4, dispersed 60 minutes wide processing. of Dispersion was according to the example. No coarse fraction was detectable by light microscopy and the relative transparency of the model film was 0.5% and did not change during the storage period of 6 weeks.

Example 4 (Comparative Example) 100 g of dibutyl phthalate are dissolved in 200 ml of ethyl acetate at 65 ° C. and dispersed at 60 ° C. for 45 minutes in 1000 ml of 10% gelatin solution containing 10 g of sodium diisobutylnaphthalenesulfonate by means of a rapid stirrer. The further processing was carried out according to Example 1.

By light microscopy, a coarse fraction of 35% by volume could be quantified. The relative transparency of the model film was 7%. After 4 weeks of storage, the relative transparency was 10%.

Example 5

50 g of a chlorinated polyethylene having an average molecular weight of 8000 and a chlorine content of 40% were dissolved in 100 ml of dibutyl phthalate and 200 ml of ethyl acetate and at 65 ⁰ C SO minutes by means of high-speed agitators in 1000ml 10%

Gelatin solution containing 5 g of Na dodecyl sulfate and 2.5 g of Compound 1 dispersed.

The further treatment of the dispersion was carried out according to Example 1. It was light microscopic no coarse fraction detectable and the relative transparency of the model layers was 1%. After a storage period of 4 weeks, no deterioration was found.

Example 6

200 g of an a-Matylstyrenoligomeren having an average molecular weight of 480 are dissolved in 300 ml of ethyl acetate and at 60 ° C for 60 minutes by means of Schneürührwerk in 700ml 10% gelatin solution containing 10g Na diisobutylnaphthalenesulfonate and 5g of the compound ß and 5g of the compound 2, dispersed. The work-up of the dispersion was carried out according to Example 1. It was possible to determine kBJn.Qrobanteil and the relative transparency of the model layer was 0%. Over a storage period of 6 weeks no changes could be detected.

Example 7

100 g dioctyl adipate are dissolved in 150ml Ethylacetut at 65 ° C and C in 45 minutes via Schnellrührwerk 100ml 10foigeroelatinelösung that 7.5 g Na-Diisobutylnaphthalinsulfonat and 2.5 g of compound 8 at 6O ^0, dispersed and further processed according to Example. 1

By light microscopy, no coarse fraction was detectable and the relative transparency of the model layer was 1%.

The quality of the layer did not change during the storage period of 8 weeks.

Claims (1)

1. A process for the dispersion of hydrophobic components for the production of gelatin-containing layers containing high-boiling solvents in disperse form, using surface-active substances as a dispersing aid, characterized in that the dispersing aid is a mixture of an anionic surfactant and a polysiloxane-polyether copolymers of the general structure ..__ :: - 'Mn - (^ ₁ - GiO) _n - (TJ ₁ - GiO) ₁₁ - Ji;: _Σ (I) and / odor f .: : i _t - CiO - (', I ₁ -: - iO) _r) · - (:?, - CiO) _{n / 2} - 3i R, (II) and / or