US3655427A

US3655427A - Correctable graphic system

Info

Publication number: US3655427A
Authority: US
Inventors: Walter J Smith; John W Rafferty
Original assignee: Parker Pen Co
Current assignee: Bankers Trust Co
Priority date: 1969-10-28
Filing date: 1969-10-28
Publication date: 1972-04-11
Anticipated expiration: 1989-04-11

Abstract

A correctable graphic system which will permit easy correction of written material by the application of a correcting fluid of dilute aqueous ammonia solution comprising: a paper base, a rubber latex or acrylic emulsion barrier coating which is insoluble in the correcting fluid and relatively resistant to the penetration of ink and a proteinaceous ink receptive surface coating which is soluble in the correcting fluid.

Description

Unite States atent Smith et a1.

[15] 3,655,427 [451 Apr. 11, 1972 154] CORCTABLE GRAPHIC SYSTEM [72] Inventors: Walter J. Smith, Arlington; John W. Rafferty, Marblehead, both of Mass.

[73] Assignee: The Parker Pen Company, Janesville, Wis.

[22] Filed: Oct. 28, 1969 211 App1.No.: 871,971

[52] US. Cl ..ll7/76 P, 117/2 R, 117/2 TC, 117/15, 117/80, 117/83,1l7/l02R [51] Int. Cl. ...B32b 25/06, B44d/14, B44d 5/04 [58] Field ofSearch ..l17/2 R,2TC, 76 P, 80, 83, 117/15, 102 R [56] References Cited UNITED STATES PATENTS 5/1938 Elliot ..ll7/76P 11/1958 l-loeletal ..117/83X 2,955,970 10/1960 Rice et a1. ..l17/83 X 3,076,720 2/1963 Rice et a1 ....1 17/83 X 3,086,884 4/1963 Betschmann ....1 17/76 P 3,468,698 9/1969 Pelletier et a1..... ....1 l7/76 P 3,494,783 2/1970 Kimura et a1. ..1 17/76 P 3,520,242 7/1970 Kemp et a1 ..1 17/76 PX Primary Examiner-William D. Martin Assistant Examiner-Ralph Husack Att0rneyBacon & Thomas [57] ABSTRACT 1 Claim, No Drawings CORRECTABLE GRAPHIC SYSTEM DESCRIPTION OF THE INVENTION Despite advances in writing instruments, inks, etc., the correction of written material is still a relatively imprecise operation usually resulting in a noticeable surface blemish. An object of the present invention, therefore, is the provision of a novel and improved correctable graphic system which will permit easy correction of written material.

A further object of the present invention is the provision of a correctable graphic system which is usable with any kind of writing instrument, ink, etc.

Further objects and improvements of the present invention will be apparent upon reading the undergoing specification and claims.

According to the present invention a correctable graphic system which will permit easy correction of written material by the application of a correcting fluid is provided comprising: a paper base, a resinous barrier coating which is insoluble in the correcting fluid and relatively resistant to the penetration of ink and an ink receptive surface coating which is soluble in the correcting fluid. There are many advantages to the novel and improved correctable graphic system according to the present invention. The correctable graphic system is applicable to every kind of writing method, etc. and no special ink or writing instrument is required. Only a specially coated paper is required and this specially coated paper is producible on standard paper finishing equipment. Various weights and kinds of paper can be employed since only the finish is special and, additionally, no dangerous or messy chemicals are required for correction.

According to the present invention, the written (handwritten, typewritten, etc.) material or line trace remains wholly in the surface coating which is removed by the application of a correcting fluid which is a solvent for the surface coating. Since the surface coating is one that can be readily dissolved, any part of the written material or line trace can be removed at will.

The base of the correctable graphic system may be an ordinary writing or typewriting paper base. It has been found necessary to provide a barrier coating overlying the paper base so that dissolved surface coating and dispersed trace line color will not strike through to the paper base. The barrier coating, therefore, must be relatively resistant to the penetration of ink (wet inks, ballpoint, typewriter, etc.), correcting fluid and solubilized surface film into the paper base. The barrier coating also serves as a support for the surface coating and should hold the surface coating away from the paper base. To accomplish this, the barrier coating must lie on the paper surface as a tight film. Latex-type resinous binders do this very well. Both rubber latices and acrylic emulsions have been employed with success. The coating weight and thickness of the barrier coating is conventional.

Overlying the barrier coating is a surface coating which is ink receptive and is adapted to receive the writing or line trace. The surface coating is the means of erasing any unwanted mark and is selectively removable. It is soluble in the correcting fluid and may be made using any of the many soluble binders. Proteinaceous coatings are preferred and as a practical matter casein works very well since it resists water wetting and is easily removed by the addition of dilute ammonia solution. Moreover, casein is a standard paper-coating material. The surface coating may be pigmented, for example, with clay and titanium dioxide. To the greatest extent consistent with its principle function, the barrier coating should be pigmented to match the surface coating or, in other words, the surface and barrier coatings should be pigmented alike so that removal of the surface coating does not result in a too noticeable surface blemish. The coating weight and thickness of the surface coating is conventional.

The correctable graphic system according to the present invention may be easily written upon using any writing instrument and ink (wet inks, ballpoint, typewriter, etc.). When an error is made, correction may be easily affected by touching the error spot with a correcting fluid in which the surface coating is soluble and the barrier coating is insoluble. The desired spot is then blotted away and the area allowed to dry. The correction may be made on the remaining surface. In the case of a casein surface coating, a dilute water solution of ammonia may be employed as the correcting fiuid and an acrylic resin as the barrier coating.

The following non-limitative example illustrates the invention:

EXAMPLE Ten (10) parts of water were added to a dry mix of 2 parts of Titanox (TiO and 18 parts of Ultraglos (clay) and the mixture was worked to a smooth paste. A solution of 20 parts water and 0.2 part oxalic acid was added to the paste while thoroughly mixing. Sixteen (16) parts of Rhoplex l-lAl2 (an aqueous dispersion of acrylic polymer available from Rohm & Haas Co.) was then added to the paste with good mixing. This composition was coated on paper stock using a No. 10 rod, air dried and then cured for 15 minutes at 300 F. Twelve (12) parts of water were added to 4 parts of casein (cold) while stirring to a paste. 0.5 part of concentrated ammonium hydroxide (NI-LOH) was added to the casein and water, stirred and heated for 15 minutes at F. (double boiler) to form a solution. Fifteen (15) parts of water were added to a dry mix formed by adding 3 pans of Titanox (TiO to 27 parts of Ultraglos 90 (clay) with good stirring until a smooth paste was formed. The casein-water solution formed above was added to the paste while stirring to a smooth coating mixture. This mixture was coated on top of the above applied base coat with a No. 10 rod, air dried and cured for 5 minutes at 130 F. The surface coating was readily removable by the application of ammonia.

We claim:

1. A correctable graphic system which will permit easy correction of written material by the application of a correcting fluid of dilute aqueous ammonia solution, said system comprising a paper base, a resinous barrier coating consisting essentially of an acrylic resin which is insoluble in said correcting fluid and relatively resistant to the penetration of ink overlying said base and an ink receptive surface coating consisting essentially of casein which is soluble in said correcting fluid overlying said barrier coating, and wherein the surface and the barrier coating both contain the same pigment.