Method and device of correcting errors on carbonless copying paper

Abstract

 A method of correcting errors on carbonless paper comprising applying over the error to be corrected a patch of adhesive material adapted to provide a carbonless image.

Description

[0001] This invention relates to carbonless copying paper.

[0002] Carbonless copying paper may take various forms which may be summarised as follows:

1. The Transfer System:

[0003] The back of the first sheet, generally referred to as 'coated back' or more usually 'CB' has applied to it micro-capsules containing a solution of colourless chromogenic chemicals (colour formers) and the front of the sheet beneath it is coated with a co-reactant (usually acidic clay or certain synthetic resins) to form a 'coated front' or more usually 'CF' sheet. When pressure is applied to the top sheet the micro-capsules are fractured releasing the colour formers to generate colour when in contact with the co-reactant. It will be appreciated that intervening sheets may be provided in which case they are coated with co-reactant on the front and micro capsules on the back. Papers of this kind are sold under the Registered Trade Mark 'Idem'.

2. Self Contained System: Type 1:

[0004] The co-reactant and micro-capsules are either in two adjacent layers with the micro-capsules applied as one layer and the co-reactant as the other on the surface of the paper, or micro-capsules and co-reactants are arranged in a mixed formation as one layer on the surface of the paper. Papers of this kind are sold under the Registered Trade Mark 'Mono-form' and 'Intus'.

3. Self Contained System: Type 2:

[0005] The co-reactant and micro-capsules are added to the paper furnish before it is made to become part of the structure of the paper sheet. Paper of this kind is sold under the Registered Trade Mark 'Action'.

[0006] At present when carbonless copies are corrected it is necessary to correct these with a ball pen and correcting fluid, or the errors have to be crossed out and retyped on a different part of the paper, and it is an object of the present invention to overcome this drawback.

[0007] According to one aspect of the present invention a method of correcting errors on carbonless paper comprises applying over the error to be corrected a patch of adhesive material adapted to provide a carbonless image.

[0008] According to another aspect of the invention a device for use in the method as set forth comprises a patch of adhesive material formed so as to be capable of being applied over an error to be corrected and adapted to provide a carbonless image.

[0009] The patch may be formed with a self contained carbonless copying system or alternatively it may be formed with a front coating adapted to co-operate with the rear coating of the preceding sheet, so as to be operable with the transfer system.

[0010] The patches may be cut off to a desired length from a strip of patch material and preferably the strip is in roll form. _- __ The adhesive may be wettable or self adhesive. In the latter case a release liner is provided, or where the strip is provided in a roll form the upper surface may be given a rclcasc coating. A strip may if desired be provided with perforations to enable this strip to be readily removed in predetermined lengths, or the strips can be mounted on a device adapted to cut it at the desired length. The width of the strip is conveniently such as to conceal the lettering to be corrected without obscuring the lettering in the adjacent lines. Typically a strip for correction of a single line could be between 4.5 and 6.0 mm although the width may be suitably varied and may be even as much as 15 mm or as little as 3mm.

[0011] The invention may be performed in various ways and one specific embodiment will now be described by way of example with reference to the accompanying drawings in which:

Fig. 1 is a view of a roll of material and

Fig. 2 is a view of patches arranged on a sheet

[0012] In the arrangement shown in figure 1 the strip is formed on one surface with a latex self adhesive material and has applied to it a release liner which may be a silicon coated release liner. The strip may be formed with a self contained carbonless copying system or it may be formed with a front coating adapted to co-operate with the rear coating of the preceding sheet. In operation the typist removes the release liner and applies it over the error to be corrected.

[0013] In a typical example the roll may be 10 to 15 metres long and is of a width of between 4 and 6 mm, preferably about 4.5mm. If desired perforations may be provided for example at 4mm intervals so that the strip can be readily detached. Alternatively the strip may be held in a dispensing device provided with a cutter.

[0014] In the alternative arrangement shown in figure 2 the patches are provided in strips on a backing sheet and can be peeled off as required. In a typical example the release liner sheet may be 6 cm by 4 cm, the individual strips 4 cm by 4.5 cm and the length of each individual section 4 mm. Thus, each sheet would contain 100 individual patches.

Claims

1. A method of correcting errors on carbonless paper comprising applying over the error to be corrected a patch of adhesive material adapted to provide a carbonless image.

2. A device for use in correcting errors on carbonless paper comprising a patch of adhesive material formed so as to be capable of being applied over an error to be corrected and adapted to provide a carbonless image.

3. A device as claimed in claim 2 in which the patch is provided with a self-contained carbonless copying system.

4. A device as claimed in claim 2 in which the patch is formed with a front coating adapted to co-operate with the rear coating of the preceding sheet.

5. A device as claimed in claim 2, claim 3 or claim 4 in which the patches are cut to the desired length from a strip of patch material.

6. A device as claimed in claim 5 in which the strip is in roll form.

7. A device as claimed in any one of claims 2 to 6 in which the adhesive is wettable or self-adhesive.

8. A device as claimed in claim 7, in which, when the adhesive is self-adhesive a release liner is provided.

9. A device as claimed in claim 6, claim 7 or claim 8 in which when the strip is in roll form the upper surface is given a release coating.

10. A device as claimed in any one of claims 5 to 9 in which the strip is provided with perforations.

11. A device as claimed in any one of claims 5 to 10 in which the width of the strip is between 15mm and 3mm.

12. A device as claimed in claim 11 in which the width of the strip is between 4.5 and 6 mm.

Drawing