JPH07116586A - Reactive liquid applying method - Google Patents

Abstract

PURPOSE:To stably applying a reactive liquid, such as an instant film stiffener on a wet layer contg. a protein binding agent with low applied quantity and at high speed. CONSTITUTION:A layer contg. a protein binding agent is formed on a supporting body 4. A coating liquid contg. a reactive liquid is caused to flow out at a flow rate of 0.4-0.7cc/cm.sec by an extrusion coater 3 to form a curtain film on the layer in a wet state. The height of the curtain film is adjusted so that the impact velocity may be 140-250cm/sec. A plate for shielding wind 2 is fitted near the curtain film on the upstream side and the application is made while the wind accompanying the coating liquid is shielded by the plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for coating a reactive liquid in which a reaction occurs immediately when two liquids are mixed, and in particular, a layer containing a proteinaceous binder and a layer containing a reactive liquid such as an instantaneous hardening agent. The present invention relates to a method of applying.

[0002]

2. Description of the Related Art As a method of applying a reactive liquid in which a reaction occurs immediately when two liquids are mixed, a method of applying a layer containing an instant hardening agent to a layer containing a proteinaceous binder is particularly useful for multi-layer color photography. It is used in a method of applying a hardener in a layer of material. (JP-A-63-61243, JP-A-63-17)
(See each report of No. 5668) As the coating method, at the lip tip of a multi-layered liquid injector containing a proteinaceous binder in a slide type multi-layer coating device, a layer containing an instantaneous hardener is poured into a thin film and joined. In this method, the combined layers are curtain-coated on a support.

[0003]

[Problems to be Solved by the Invention] Reactive liquids (such as highly reactive cationic dyes, mordants, fast-acting hard blink agents)
For example, a rapid-acting hardener has a very fast hardening reaction, and thus can be expected to have many merits such as a reduction in the amount of stock and a shortened research cycle because it is completed as a product in a short time after application. However, on the other hand, there is a demerit that it is difficult to handle because the liquid thickens violently after mixing with the protein to be hardened. In order to solve this problem fundamentally, the present invention applies a hardener and a protein onto a wet layer by a separate coater that does not mix and contact not only in a solution preparation tank but also in a liquid injector. Adopt the method. When coating with a separate coater, stable high-speed coating with a low flow rate and a low coating amount is required for coating the reactive liquid. In the present invention, curtain coating is used for coating a layer containing a reactive liquid, but problems that hinder high-speed coating, such as air entrainment and film-stretching development, must be solved. . Therefore, it is an object of the present invention to provide a reactive liquid coating method that solves the above problems and enables stable high-speed coating.

[0004]

The above object of the present invention is to provide a method of coating a layer containing a reactive liquid on a layer containing a proteinaceous binder, wherein a layer containing the proteinaceous binder is used as a support. A coating liquid containing the above-mentioned reactive liquid was formed on the wet layer by an extrusion coater at a flow rate of 0.
The flow rate is 4 to 0.9 cc / cm · sec to form a curtain film, and the collision speed to the wet layer is 140 to 250.
The reactive liquid is characterized in that the height (h) of the curtain film is adjusted to be cm / sec, and a wind shield is provided near the upstream side of the curtain film to block entrained air while performing coating. How to apply. The distance (D) between the wind shield and the curtain film before the curtain film is 3 to 30 mm, and the clearance (C) between the lower end of the wind shield and the support is 0.1 to 1.0 mm. This is achieved by the method of applying the reactive liquid described above.

As shown in FIG. 1, when another coating liquid film is overlaid on a wet coating liquid film applied by slide coating or another coating method and curtain coating is performed, the curtain film collides with a support. It was found that by increasing the speed and additionally using a wind shield, the coating limit speed in the low flow rate region of the unit width flow rate was improved, and low coating amount and high speed coating could be realized. This is because the film pulling phenomenon can be suppressed by increasing the collision speed, and the air entrainment can be suppressed by using the wind shield. It is also effective to reduce the surface tension of the overcoat layer. Specifically, the unit width flow rate is 0.4 ~
0.7cc / cm ・ sec, impact speed 140-250cm / sec, windshield conditions D = 3-30mm distance from curtain membrane, support clearance C = 0.1-1.0mm can get. The conditions of curtain coating according to the present invention can be applied to other general curtain coating. In the present invention, the unit width flow rate is 0.4 to 0.7 cc
/ Cm · sec means 0.4 cc / cm · sec
Below, the coating limit speed drops sharply, and maintaining the curtain film itself is difficult. 0.7 cc / cm · sec
Even with the above, the coating limit speed drops sharply. The collision velocity to the lower layer at that time depends on the height H of the curtain film.
~ 250 cm / sec is preferred. By doing so, the coating limit speed can be maintained at 300 m / min or more.

The effect of the present invention is further enhanced by the air-shielding operation of the air entrained in the support. The purpose can be achieved by keeping the clearance c between the lower end of the wind shield and the support c = 0.1 to 1.0 mm and the distance D between the wind shield and the curtain film = 3 to 30 mm. As shown in FIG. 1, the coating apparatus of the present invention is often a multi-layer simultaneous slide coater 1 for a layer containing a proteinaceous binder, but other liquid injectors may be used. A curtain coat of an extrusion coater 3 provided with a wind shield 2 is used for a layer containing an instantaneous hardening agent applied to the upper layer. A layer containing a proteinaceous binder is first coated on the support by the multilayer simultaneous slide coater 1, and then a curtain of a liquid containing a reactive liquid formed by the extrusion coater 3 is formed on the wet layer. Coating is performed by colliding the film.

[0007]

EXAMPLE Coating was carried out by a coating apparatus as shown in FIG. As a component of a liquid containing a proteinaceous binder, alkali-treated gelatin as the first layer 3.80% by weight 2-ethylhexyl sodium α-sulfosuccinate 0.15 sodium polystyrene sulfonate 0.11 as the second layer Is a two-layered solution of an aqueous solution containing alkali-treated gelatin 8.1% by weight sodium α-sulfosuccinate 2-ethylhexyl ester 0.15, and the component of the solution containing the reactive liquid is sodium polystyrene sulfonate 1. An aqueous solution containing 5% by weight of α-sulfosuccinic acid 2-ethylhexyl ester sodium 0.15 was used.

Regarding Examples 1 to 4 and Comparative Examples 5 to 9, the conditions for coating the liquid containing the reactive liquid, that is, the flow rate, the curtain film conditions, the wind shielding conditions, etc. were as shown in Table 1. The results are comparatively evaluated at the limit speed at which stable coating is possible, and shown in Table 1.
The curtain collision speed U (cm / sec) is expressed by U ² = U _o ² +2 gH. Where U _o : initial velocity (cm / sec) of the liquid flow at the slit exit of the extrusion coater,
g: acceleration of gravity (cm / sec ² ), H: curtain height (cm). The initial velocity U _o is obtained by dividing the flow rate per unit width at the slit outlet by the slit clearance. From the results in Table 1, it can be seen that the coating limit speed is significantly increased in Examples 1 to 4 which satisfy the requirements of the present invention.

[0009]

[Table 1]

[0010]

EFFECTS OF THE INVENTION By the curtain film forming conditions of the instant hardener of the present invention, it becomes possible to particularly improve the coating limit speed in the low flow rate region near the lower limit of the curtain film formation, and a high-speed method for coating a reactive liquid can be obtained. Thin layer coating became possible.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of a wet-on-wet used in the reactive liquid coating method of the present invention.

FIG. 2 is a partial side view of a method of providing a windshield for curtain coating by the extrusion coater of the present invention.

[Explanation of symbols]

 1 Multi-layer simultaneous slide coater 2 Wind shield 3 Extrusion coater H: Height of curtain film D: Distance between wind shield and curtain film C: Clearance between bottom end of wind shield and support surface

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[Procedure amendment]

[Submission date] January 25, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 2

[Correction method] Change

[Correction content]

Claims (2)

[Claims] 1. A method of applying a layer containing a reactive liquid onto a layer containing a proteinaceous binder, wherein the layer containing the proteinaceous binder is formed on a support, and the layer containing a wet state is formed on the support. The coating liquid containing the reactive liquid was caused to flow out from the extrusion coater at a flow rate of 0.4 to 0.7 cc / cm · sec to form a curtain film, and the collision speed of the wet layer was 140
Reactivity characterized in that the height (H) of the curtain film is adjusted to be ~ 250 cm / sec, and a wind shield is provided near the upstream side of the curtain film to block entrained air while performing coating. Liquid application method. 2. The distance (D) between the wind shield and the curtain film.
= 3 to 30 mm, and the clearance (C) between the lower end of the wind shield and the support is 0.1 to 10 mm, and the method for applying a reactive liquid according to claim 1.