US517034A - Slate or blackboard eraser - Google Patents
Slate or blackboard eraser Download PDFInfo
- Publication number
- US517034A US517034A US517034DA US517034A US 517034 A US517034 A US 517034A US 517034D A US517034D A US 517034DA US 517034 A US517034 A US 517034A
- Authority
- US
- United States
- Prior art keywords
- slate
- blackboard eraser
- pulp
- dempsey
- erasing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000010454 slate Substances 0.000 title description 10
- 239000000463 material Substances 0.000 description 14
- KMUONIBRACKNSN-UHFFFAOYSA-N Potassium dichromate Chemical compound [K+].[K+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KMUONIBRACKNSN-UHFFFAOYSA-N 0.000 description 4
- 229920001131 Pulp (paper) Polymers 0.000 description 4
- CVHZOJJKTDOEJC-UHFFFAOYSA-N Saccharin Chemical compound C1=CC=C2C(=O)NS(=O)(=O)C2=C1 CVHZOJJKTDOEJC-UHFFFAOYSA-N 0.000 description 4
- 229940081974 Saccharin Drugs 0.000 description 4
- 235000019204 saccharin Nutrition 0.000 description 4
- 239000000901 saccharin and its Na,K and Ca salt Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 239000001828 Gelatine Substances 0.000 description 2
- 241000206672 Gelidium Species 0.000 description 2
- 206010022114 Injury Diseases 0.000 description 2
- 229920000159 gelatin Polymers 0.000 description 2
- 235000019322 gelatine Nutrition 0.000 description 2
- 108010059642 isinglass Proteins 0.000 description 2
- 229910052627 muscovite Inorganic materials 0.000 description 2
- 239000000123 paper Substances 0.000 description 2
Classifications
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
- A47L25/00—Domestic cleaning devices not provided for in other groups of this subclassÂ
- A47L25/005—Domestic cleaning devices not provided for in other groups of this subclass using adhesive or tacky surfaces to remove dirt, e.g. lint removers
Definitions
- the object of my invention is an improved slate and blackboard eraser to produce a superior erasive material for the purpose of erasing chalk, slate or crayon marks from slates and blackboards.
- I add to ordinary paper pulp, preferably that known as blotting paper pulp, a solution composed of one part of saccharin, three parts of potassium bichromate and six parts of gelaaside from the water, bearing the relation of about one part of chemicals to ninety nine parts of dry paper material. While the proportions of the chemicals as stated are preferably used, they may be varied both with relation to each other and to the pulp.
- the pulp having been thus treated is under heat and pressure, made into dry sheets, the dimensions and thickness of which may be varied at will.
Description
, tine or isinglass, such solution,
UNITED STATES PATENT OFFICE.
DOMINICK E. DEMPSEY, OF GENEVA, NEW YORK.
SLATE OR BLA CKBOARD ERASER.
SPECIFICATION forming part of Letters Patent No. 517,034, dated March 27, 1894. Application filed July 8,1893. Serial No. 479,461- (No specimens.)
To all whom it may concern.-
Be it known that I, DoMINIoK E. DEMPSEY,
a citizen of the United States, residing at Ge-,
neva, in the county of Ontario and State of New York, have invented certain new and useful Improvementsin Slate and Blackboard Erasers; and I do hereby declare the following to be afull, clear, and exact description of theinvention, such as will enable others skilled in the art to which it appertains to make and use the same.
The object of my invention is an improved slate and blackboard eraser to produce a superior erasive material for the purpose of erasing chalk, slate or crayon marks from slates and blackboards. For this purpose, I add to ordinary paper pulp, preferably that known as blotting paper pulp, a solution composed of one part of saccharin, three parts of potassium bichromate and six parts of gelaaside from the water, bearing the relation of about one part of chemicals to ninety nine parts of dry paper material. While the proportions of the chemicals as stated are preferably used, they may be varied both with relation to each other and to the pulp. The pulp having been thus treated, is under heat and pressure, made into dry sheets, the dimensions and thickness of which may be varied at will. These dry sheets are then divided into small masses, blocks or tablets, suitable to be held conveniently in the hand and used for the purposes mentioned. The material obtained by this process iseconomical in cost, light in weight, readily made into convenient shapes and sizes, compact and durable, and remarkably effective for completely erasing, with slight friction, chalk, slate and crayon marks from slates and blackboards, without doing any injury to the surfaces thereof. In using this material for such erasing purposes, it is unnecessary to use water or other moisture. In these respects this material is superior to any other material heretofore used for the purposes described.
Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-
A block, tablet or mass of erasive material for the purpose set forth, composed of paper, gelatine, saccharin, and potassium bichromate, substantially as described.
In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.
DOMINIOK E. DEMPSEY.
Witnesses:
ALBERT B. GUILBERT, J. H. PICKETT.
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US517034A true US517034A (en) | 1894-03-27 |
Family
ID=2585839
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US517034D Expired - Lifetime US517034A (en) | Slate or blackboard eraser |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US517034A (en) |
-
0
- US US517034D patent/US517034A/en not_active Expired - Lifetime
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