DE1209467B - Device for applying fluids to tapes - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

ALAJk

GERMAN AW ^ PATENT OFFICE

EDITORIAL

Int. α .:

B 05 c

Number:
File number:
Registration date:
Display day:

German KI .: 75 a-20

1 209 467
P21219Ib / 75a
20th August 1958
20th January 1966

The invention relates to a device for applying liquids to tapes, in particular of aqueous binders for photographic purposes, with an excess application and subsequent coarse and fine stripping of the excess liquid from the upwardly guided Band through a squeegee and an air knife.

The use of air knives is in the art of applying photographic material Carrier tapes known. The use of squeegees for smoothing and for Regulating the thickness of the coatings applied.

The invention provides a device for applying liquids to tapes, which makes it possible to obtain a coating with a surprising degree of smoothness and uniformity and the speed at which the coating is applied versus known devices to enlarge for this purpose. This is possible because in the device according to the invention the scraper bar located below the air knife is a sloping downward from the belt has flat excess surface and the bar with respect to the tape guide perpendicular, parallel and adjustable in angle and attached to the air knife carrier with its adjustment device is.

The invention is based on the knowledge that the relative position of the squeegee to the tape and the air knife has a major impact on the quality of the subsequent coating, and the essential Advantage that the device according to the invention has over the known devices, are the various setting options available with her for the squeegee compared to the Air knife carriers that allow the most favorable setting for the respective material to be applied to undertake. There is a uniform discharge for the air knife flow.

The air knife carrier can preferably be swiveled away from the tape guide so that it is possible to close to gain access to the tape or to insert a new tape without subsequently re-adjusting the device to have to.

The use of the coatings according to the invention is particularly favorable with regard to the achievable quality of the coatings Device with an excess application device in which the application thickness is adjustable is.

A preferred embodiment of the device according to the invention is shown in the drawing. It contains a device for applying liquids
on tapes

Applicant:

E. I. du Pont de Nemours and Company,

Wilmington, Del. (V. St. A.)

Representative:

Dipl.-Ing. E. Prince and Dr. G. Hauser,

Patent attorneys,

Munich-Pasing, Ernsbergerstr. 19th

Named as inventor:
Charles Francis LeClaire,
Little Silver, NJ (V. St. A.)

Claimed priority:

V. St. ν. America dated August 21, 1957 (679 342)

F i g. 1 a side view of the device according to the invention,

F i g. Fig. 2 is a schematic representation of a photographic film manufacturing plant using the device according to the invention for applying a photographic coating on the tape.

The device has an air knife 1, a squeegee 2, and a roller 3 serving to guide the tape and a pan 4. The desired thin layer of viscous liquid coating material 5 is applied to her applied by lifting the material from a liquid surface on a flexible belt 6, the moves forward continuously in the direction indicated by the arrows.

The air knife 1 is attached to a frame, not shown. It is adjustable in a known way, so that it is possible to have a plane stream of air at any angle on the coated To let tape hit. At each end of the end wall 8 of the air knife is near the Air outlet opening 9 a pin 7 attached. The pins 7 hold together with nuts 11 the upper bracket 10 of the adjustment mechanism for the squeegee 2.

509 779/126

3 4

The squeegee 2 is arranged so that its at least 200%, preferably 450 to 550%, of the lip 12 is parallel to the surface of the roll 3, desired final thickness of the wet coating and it extends across the roll over a amounts to. The thickness of the stretch applied to the pan, which is at least as long as the overcoating, is determined by the dam 21,
pulling tape 6 is wide. In addition to the lip 12, 5, it is also advisable to arrange the lip 12 of the deflector, as shown, through a strip 2 adjacent to the roller, shortly before the point where the outgoing band makes contact with the roller on the hard, machined protruding part is used, the squeegee 2 has an upper surface 13 lined. In the proposed position, the air surface and a lower surface 14 for returning the overflow from the outlet opening 9 meet with a coating material that is still in contact with one another in the pan. The part of the upper surface 13 which is in contact with the roller 3 goes downwards in a curved band onto the coating material.
shaped projection 15 over which the excess lip 12 is attached so close to the tape. Directs material from surface 13 into the pan. One that they removed a portion of the freshly applied coating pin 16 for attaching the squeegee 2 to materials. It is of great importance that the adjustment mechanism is on each side of the device that no air, especially no air from the bar is attached by clamping fits. the air knife, between the lip 12 and the

The adjustment mechanism is so that the air band can pass through it. It was the same for

knife carrier 1 mounted that the exact setting found necessary to arrange the lip 12 so

the squeegee 2 regardless of the air knife that it lets through more coating material than for

can be made. It is extremely important 20 the final product is required. In particular

that the distance y of the lip 12 from the other should be the amount of coating material which

going tape 6, the distance ζ between the Ab- on the lip 12 can get past, or what

strip strip 2 and the air outlet opening 9 and which is equivalent, the distance between the lip 12 of

Angle Ö, which the band with the upper surface 13 of the band 6 at least 120%, preferably between

the squeegee 2 includes, precisely set 35 see 120 and 150 ° / o, the final thickness of the

can. wet coating.

The adjustment mechanism has upper brackets 10 The covering material which passes through the lip 12

and lower bracket 17, which is retained together, flows on the lower surface 14

are bound. One attached to the upper bracket 10 of the squeegee 2 in a smooth stream into the

Adjustment screw 18 enables a more precise approach 30 from the tub 22. The angle at which the lower surface

lead and retract the squeegee 2 to 14 depends on the design of the

the distance between the lip 12 from the strip squeegee 2 and is not critical,

to be able to adjust. Similarly, the air knife 1 must be so arranged

an adjustment screw 19 to precisely adjust that there is an air flow at an angle

and withdrawing the squeegee 2 in a vertical 35 35 to 90 °, preferably 45 to 55 °, against there;

Direction to it so as to direct the distance between the coated tape. This angle is used by de;

The scraper bar 2 and the air outlet opening 9 are one level of the outgoing belt (or given

to be able to provide. In addition, the squeegee 2 is de if of the role at the point of impact;

pivotable about the axis of the pin 16, so that the air flow tangential plane from) against the dei

the angle between the tape and the top 40 measured clockwise.

Area 13 of the squeegee can be changed. The optimal distance between the hit line

The selected angle setting is determined by the intake of the air stream and the lip 12 can be according to be

Maintain adjusting screw 20. certain variable, like the viscosity de:

The pan 4 is divided into separate sections. Coating material or the speed, mi

It will vary from the outside with coating material 5 to which the coating is applied. Ii

supplies that to a large extent via a dam most of the time it will preferably be there:

21 overflows into a tub 22, which is also 1 to 5 times, in particular 2 to 3 times de

Collecting container for the final thickness of the moist coating along surfaces 13 and 14

the squeegee 2 draining excess transfer,

pulling material is used. 50 The angle between the top surface 13 de

The dam 21 is parallel to the peripheral surface of the squeegee 2 and the plane of the tape to de

Role 3 arranged and is slightly lower than the scraping line of the lip 12 is critical. He is opposed

Rear edge 23 of the pan 4, so that the coating in a clockwise direction from the upper surface 13 from ge

Measure the material only in the direction of movement of the belt and denote it as the angle Θ in the following!

overflows. The over 55 collected in the tub 22 is of great importance to this angle Θ

Tensile material is at least as large, preferably 5 to 15, by means of a not shown

Facility again to dimension the pan 4 supplying greater than the angle under which

Coating liquid flow supplied. The pan 4 deflates after hitting the coating

can be adjusted in the lateral and vertical direction material from the coated surface of the band

so that it is possible to have the application thickness reflected at 60. This ensures the stability of the air

cease the excess application. current and the current removed coating

The above settings are made within materials downwards over the area 13. Let be

certain, listed in more detail below, it notes that the angle of incidence of the air knife air

kept shear limits and then lead to the currents not necessarily equal to the reflection

desired results. The pan must be at a 65 angle to the airflow.

such position relative to the belt. The air flow forming the air knife was asleep

be that the tape due to the excess application with the outgoing tape an angle β , un

is provided with a coating, the thickness of which is reflected at an angle cv, the small

5 6

is as large as or as large as the angle θ between the air flow and the flow occurring on the coating.

the upper surface 13 of the squeegee and the ming lines. Without the upholstery

Tape. the flow lines through the air knife do not

During the operation, the dam 21 serves in part to be removed.

It has also been found that the material of the invention remains in the pan. The coating material removed by the device according to the invention as a result of the stabilization of the lip 12 flows smoothly and the airflow, the feared, aforementioned airflow, is constantly downward along the surface 14, into which fluttering is avoided.
Tub 22.

Excess coating material, which is due to io
the air knife airflow has been removed and the der in FIG. The apparatus shown in the drawing in the known covering devices with air is set so that the air knife air flow flows back down the belt or as a spray at an angle β of about 52 ° on the coated rain or in the form of mist particles from the belt . The air knife is located 2.54 mm tape flows away, the pan is removed in the form of a 15 from the tape. The air knife pressure, smooth, along the upper surface 13 of the carries 146.8 mm water column, with an outlet squeegee of flowing flow again being used as a draw opening of 0.63 mm. The stripping leads. In this way, the risk of a strip bar is set in such a way that the lip 12 is in the process of being formed by a distance of 0.33 mm away from the belt and a distance of 0.33 mm from tensile material and a deposition of spray rain. The distance between the impingement line of the or mist particle on the smoothed part of the air knife air flow and the upper edge of the coating and thus damage to the same lip of the squeegee 2 is 0.76 mm. The side. Angle Θ is about 68 °. A cellulose acetate film

The invention is particularly advantageous for the carrier moving at a speed of

Application of aqueous photographic material. 25 67 m / min and is operated with a light-sensitive

A preferred application of the invention is in photographic gelatin silver bromide chloride insulin the application of a coating from a region coated which has a viscosity of 10.6 cSt Latin silver halide emulsion. In Fig. 2 of the drawing - at a temperature of 38 ° C - and 16 Genung is one of the usual weight percent solid components according to the general principle. Man order shown schematically for this purpose. 30 holds a coating of about 135 mg of solid

A tape, film carrier or paper runs from parts per square decimeter. The resulting, with

a supply drum 24 in the indicated Rieh- this emulsion coated film shows an excellent

management around a guide role 25, then around the role 3 outstanding quality and uniformity of his

at the workstation at which the cover has sensitivity and other properties,
is brought (Fig. 1), further on a guide 35

roll 26 past, through a known cooling zone 27 example 2
through which the emulsion is solidified,

from there around a guide roller 28, then as in example 1, but with the difference,

through a known drying apparatus 29 through that the air knife pressure 94 mm water column and

and finally to a take-up drum 30 or 40, the distance between the metering lip and the

possibly also to another workstation. Tape is 0.508 mm and the angle between

The reason for the excellent results that the squeegee and the belt are around 65 ° in size.

under the above-mentioned conditions by means of an aqueous, light-sensitive photographic process

device according to the invention are achieved, is latine silver iodobromide emulsion for X-ray

Probably in that the air knife airflow. 45 radiate with a viscosity of 26 cSt - with a

after getting the last excess coating temperature of 38 ^: C - and 16 percent by weight

material has worn away and the coating of solid components is on a gelatin-coated

was reflected, applied by the squeegee 2 stabili- Polyäthylenterephthalatband, which

is sated and moves in a smooth, eddy-free stream at about 45.72 m / min. You get one

runs along the upper surface 13 of the bar. 50 coating of approximately 227 mg of solids per

This has the consequence that the excess coating square decimeter, which is an emerging quality

material is held on the surface 13 and at the same time and excellent sensitivity and others

flows moderately and gently into the tub 22. Has properties.

Another reason for the excellent, ins- _R. . . ,

especially at high stall speeds up to 55 eggs

Achieving results is probably in the fact, As Example 1, but with the difference that that as the excess coating is removed, the distance between the lip and the tape materials from the tape through the air knife-air is 0.178 mm. A paper tape made of light current a small pool of covering material on the weighty material, such as that used for files The upper part of the point of contact between the 60 is moving at a speed of going tape and the upper edge of the stripping about 45.72 m / min and is made with a coating bar 2 is formed. This cushion forms a re-a photographic light-sensitive gelatin reservoir, which material to any in the silver bromide chloride emulsion which in a Tem coating provides existing cavities. At this temperature of 38 ° C a viscosity of 8.4 cSt and Thus, the coating material provides the air stream 65 with a solid content of 11 percent by weight Uniform surface, which has irregular components, coated. You get one inconsistencies and irregularities avoided by about 30 mg of solid components per coating which are caused by the impact of the square decimeter, which is an excellent qua-

i 209 467

lity and excellent sensitivity and others Has properties.

The excess application can of course also take place in a way other than the lift-off method.

In addition to silver halide emulsions, the device according to the invention is also suitable for application other coating materials such as gelatin sheets, gelatin filter sheets, layers for preventing from wear and tear and anti-static layers. It's also useful for the application of layers of paint to films and paper tapes and the like.

The device according to the invention is usually appropriately adjusted so that a coating material layer with a thickness of at least 200 ¹⁰ Zo, preferably 450 to 550%, of the desired final thickness in the wet state is applied to the carrier tape, this layer along a first, transversely to The line extending across the belt is reduced to a lesser thickness of at least 120%, preferably 120 to 150%, of the desired final thickness when wet and finally the desired final thickness along a second line extending across the belt through the air knife air flow is set, which strikes the tape at an angle β of 35 to 90 °, preferably 45 to 50 °, and strips off the excess material. The second transverse line is located at a distance of 1 to 5 times, preferably 2 to 5 times the desired final thickness of the moist coating from the first transverse line. In addition, the air knife air flow after its reflection on the second transverse line is preferably diverted at an angle which, starting from the plane of the strip at the first transverse line, is at least as great as the angle between the reflected air flow and the plane of the strip on the second transverse line, preferably even 5 to 15 ° larger than this angle, while both the incident and the reflected air flow are prevented from coming into direct contact with the incoming strip at any point in front of the first transverse line.

Unexpectedly advantageous results in terms of sensitivity and photographic quality The quality of the end product is obtained when using those set in the above manner Device according to the invention for producing a coating from an aqueous gelatine-silver halide dispersion.

The device according to the invention is easily adjustable and easily accessible for cleaning and maintenance. Another advantage of it is that no coating material is wasted because the entire amount of stripped material is returned.

The entire stripping device including the air knife can easily be moved out of the working position and back into it by means of a single movement, so that it is not necessary to re-adjust the distance between the lip of the squeegee and the distance between this lip and the air knife outlet opening or the angle Θ to adjust.

Claims (3)

Patent claims: 1. Device for applying liquids to tapes, especially aqueous ones Binders for photographic purposes, with an excess application and afterwards Coarse and fine stripping of the excess liquid from the upwardly guided belt by a squeegee and an air knife, characterized in that the underneath of the air knife (1) arranged scraper bar (2) a sloping downward from the belt has flat excess guide surface and that the bar (2) with respect to the tape guide (3) vertically, parallel and angularly adjustable as well as with its adjustment device on the air knife carrier (7) is attached. 2. Apparatus according to claim 1, characterized in that the air knife carrier (7) of the tape guide (3) can be swiveled away. 3. Use of the device according to claim 1 or 2, with an excess application device, in which the application thickness is adjustable. 1 sheet of drawings 509 779/126 1.66 © Bundesdruckerei Berlin