DE1045543B - Translucent, electrically conductive layers and processes for their production - Google Patents

Description

GERMAN

The invention relates to translucent, electrically conductive layers and their production. These layers are needed for many purposes, e.g. B. for electroluminescent and photoconductive Devices.

Many methods of making such layers are known. There are e.g. B. a number of metal oxides, which can be deposited on glass-like surfaces at high temperatures and which deliver highly transparent, conductive films. A typical such procedure is that of hot Glass subjected to the action of tin chloride. This method is only applicable for glass surfaces, insofar temperatures of a few hundred degrees Celsius are required.

Conductive, translucent films can also be applied to smooth, flat surfaces by vapor deposition of graphite be produced in a vacuum or by other application.

The invention leads to a translucent, electrically conductive layer on a base which does not necessarily have to be smooth or flat and, in addition, does not have to be at an elevated temperature during manufacture needs to be exposed.

According to the invention, there is the transparent, electrically conductive layer, which in particular acts as a cover electrode suitable for luminous capacitors and photoelectroluminescent light amplifiers and on the luminous or the surface to be illuminated is applied from a thin, tightly packed, single-layer layer Made of the smallest possible glass beads, which stick to the base and, moreover, preferably over half of them Height in a network that is also opaque, but electrically conductive and that extends around the sides of the Glass bead extends around, is embedded.

The glass beads are known under the name »Ballotini« and are preferably used in one layer, which has the strength of a single pearl. The "Ballotini" beads have a diameter of about 0.05 to 0.5 mm. It has been found that a large part of the incident light passes through the beads can pass through and the layer is therefore translucent, even if the conductive mesh is opaque is.

If it is desired that the layer be conductive over both the beads and the interstices should be, the beads can be made electrically conductive before they are applied to the substrate will. This can be B. done by treating the hot beads with tin chloride or circulate it for a few hours in a mill with a small amount of graphite, which gives the surface a receives thin polished graphite layer, which is electrically conductive and allows light to pass through.

Translucent, electrically conductive

Layers and procedures

for their manufacture

Applicant:

Thorn Electrical Industries Limited,

London

Representative: Dr.-Ing. E. Liebau, patent attorney,
Göggingen via Augsburg, Von-Eichendorff-Str. 10

Claimed priority:
Great Britain 20 August 1956

Derek Hubert Mash, London,
has been named as the inventor
25th

The beads can be attached to the surface of the pad by a variety of methods. A satisfying one Method consists, as has been found, in thinning the surface of the support with a Pouring a solution of a synthetic resin that remains sticky when the solvents have evaporated. the Beads can then be rolled or shaken onto the surface, attached to which they are densely packed Cling to arrangement.

The conductive material used to form the network can e.g. B. a suspension of silver in toluene or a conductive powder, e.g. B. silver or graphite. This can be done with a brush or otherwise applied. If silver powder is used, the mesh obtained is very low electrical resistance, but it remains translucent.

If necessary, a layer can be made over the beads after the conductive mesh has been applied Apply translucent or clear plastic. This way both the scatter as well as the adsorption of light can be reduced, and layers with a high light transmission can be created of 60% or more can be produced.

The invention is described using the drawing for illustrative purposes:

809 697/276

Claims (1)

3 4 Fig. 1 is a greatly enlarged cross-section of moderately light emitted, showing translucent, electrically conductive layer that ensures that the conductivity is the same everywhere. If you use was made according to the invention; furthermore spheres with a diameter of Fig. 2 is an enlarged cross-section of an electro-0.06 mm, then it is not possible to see the pattern of the luminescent cell according to the invention; 5 network to be discovered in the distribution of light. In Fig. 3 is an enlarged cross-section of a; in this case it is not necessary, as has been found, times light amplifier according to the invention. to make the surfaces of the balls conductive. Referring to Fig. 1: The top of a plastic pad. The invention is of particular value for the Her-10 is covered with a diluted plastic solution 11 of translucent, conductive coatings rinses that remain sticky when the solvent ver io on plastic surfaces, which have previously been economical are. borrowed was not yet possible. Such a plastic example A suitable solution is the following: body is e.g. for electroluminescent lamps Beetle resin BA502 100g valuable. ..,. ". , - .. ~ \ y \ ₀ ] ^ QQ (T _m 3 Line other possible uses for the Butvl alcohol 25 cm ^{3 15} ^ ^{n <} ^ ^un S consists in the fact that the surface of a photoconductor in a light amplifier becomes electrically conductive Beetle resins are alkylated urea-formaldehyde-making, while sufficient permeable resins, as it is produced by the British Industrial Plastics, which ensures that what is incident Limited «, and such a resin light activates the photoconductor. with the designation BA 502 is a solution of a with 2 ° An example of this is given in Fig. 3, in Alkyd modified resin (alkyd resin). which a glass base 19 is shown, the upper After evaporation of the solvent, side with a translucent electrically conductive the globules 12 rolled onto the sticky surface is provided with a layer 20 of tin oxide. Above the layer or shaken, to which it is tightly packed - 20 is a layer 16 of electroluminescent material be liable. ² 5 teriäl, which is covered with a layer 21 of a pholoconductive Then a suspension of silver is covered in toluene or capable material. The beads 12, which are a conductive powder, e.g. B. silver or graphite, by means of a conductive network 13 and the outer coating 14 are applied with a brush or in some other way, and as described in Fig. 1, over the layer 21 in this way an electrically conductive network 13 is brought. An AC power source 18 can be formed with the around the beads. The conductive coating network 13 and the layer 20 are connected, material 13 mostly shows no tendency to the surface of the beads, but if it is through the glass substrate 19, an image is created on the surface 15 an image with greater light adheres, visible from the upper intensity facing the outside,
surface can be easily wiped away. Then a layer is applied by spraying with a brush or in some other way.
14 made of translucent or transparent plastic attached over the beads and forms a 1. Translucent, electrically conductive layer, smooth outside 15. In particular, cover electrode for luminous condensers The measurement of the resistance of a conductive generator and photoelectroluminescent light amplifier Layer is usually placed between two parallel 40 kers, characterized in that the translucent conductive strips in contact with the layer-permeable layer that is on the luminous or too guided. This method can, in some cases, be applied from a backlighting underlay Provide leading results because the layer is made up of a thin, tightly packed, single-ply layer \ ^{r there is a} large number of electrically isolated elements with as few as possible small glass beads (12), which are attached to conductive lines that stick between the conductive 45 of the base (10 .. 16, 21) (11) and in the Extend strips, as well as be formed from elements remaining, preferably over half their height, in who happen to be in contact with each other. In an opaque, electrical but good In these cases, the measured resistance leading network (13), which is laterally around the may be considerably low, but for most cases glass bead extends around, is embedded. such a measurement is unsuitable. 50 2. Translucent, electrically conductive layer An application of the invention extends to claim 1, characterized in that the an electroluminescent lamp, whose working surface of the glass beads itself with a through one clear indication of the quality of the conductive, electrically conductive material Shift there. So one can be used according to the invention. Provides a conductive mesh as one electrode of a 55 3. Translucent, electrically conductive layer serve such lamp, the other electrode according to claims 1 and 2, characterized thereby neither an opaque conductive layer or one that distinguishes the network from a conductive one is another layer produced according to the invention. Material, e.g. B. silver, there is no isolating Thus, as shown in FIG. 2, the spheres 12 are formed as the surface layer when the as described in Fig. 1, on a layer 16 is exposed to a 6c atmosphere. electroluminescent phosphor, which is on a 4th translucent, electrically conductive layer Metal plate 17 is applied, the layer 16 according to claims 1 to 3, characterized thereby the pad 10 of Fig. 1 replaced, attached. This shows that a translucent or translucent tend network 13 is with one end of a visible final layer (14), which over the glass AC power source 18 connected, while the other 65 bead forms a smooth surface (15). End of the alternating current source with the base plate 17 5. The method according to claims 1 to 4 for is connected. Formation of a translucent, electrically conductive If a layer is placed between the electrodes 13 and 17 on a luminous or illuminated if there is sufficient tension, it is found that the underlay, characterized in that The entire area covered by the electrodes is equal to a thin, single-layer layer of the smallest possible glass beads on the surface of a fluorescent or fluorescent material that serves as a base Photoschioht, then an opaque, but electrically conductive paint or a powder applies, such that around the glass beads around an electrically conductive Network trains. 6. The method according to claim 5, characterized in that finally the superficial of the Painting of cleaned glass beads to create a smooth surface that closes off from the outside In addition, a top layer of transparent or translucent material is poured over it will. 1 sheet of drawings