DE2049279C3 - Pressure sensitive copier paper - Google Patents

Description

V ^s χ / * = ■
/ \ _N , · \ _o -;

R,

R-

wherein R, an alkyl group having 1 to 4 carbon atoms, R ₂ and R ₃ each have a hydrogen atom, a halogen atom, a nitro group, an alkoxyl group having 1 to 4 carbon atoms in the alkyl group, an alkoxycarbonyl group having 1 to 4 carbon atoms in the alkyl group or represent an aldehyde group.

2. Pressure-sensitive copier paper according to claim 1, characterized in that the connection from 3 - methylspiro - [benzothiazoline-2,2'-2'H- (1,3) -benzoxazine], 3-methyl-6'-nitrospiro- [benzothiazoline-2.2'-2'H- (1.3) -benzoxazine ~]. 3-methyl-6'-nitro-8'-formylspiro- [benzothiazoline-2,2'-2'H- (1,3) -benzoxazine], 3-methyl-6 ', 8'-dibutylspiro - [benzothiazole - 2,2' - 2Ή - (1,3) -benzoxuzin] or 3-methyl-6'-mtro-8'-methoxyspiro- [benzothiazoline-2,2'-2 H- {1,3) -benzoxazine].

35 layering on a paper, and in some cases a sheet containing the microcapsules as a coating on one side and the electron accepting substance on the other side will be deceptive. between the two leaves given above. or it can be a sheet which simultaneously soaks the microcapsules and the electron-accepting substance as a coating on the pale surface of the paper. come into use. I _n any case, the microcapsules are ruptured by the write or copy printing, and the solution of the given Farbbitdners then is contacted with the electron-accepting substance into contact with a colored copy image obtained ν ird.

The principle, the shape and the manufacturing process, as described above, are known. . (val. USA. Patents 2548 3M. ₁ 2 711 375. 2 730 456. 2 730 457 , 2 812 50 ". 2800 45" and 2 "800 458).

The object of the invention is to create a, improved pressure-sensitive copier paper which a new compound is used as a color former.

The pressure-sensitive copying paper according to the invention which has a coating on a support Has microcapsules which contain a compound with an electron accepting substance results in a color reaction, is characterized by the fact that the compound has the general form!

The invention relates to pressure sensitive copier paper.

In general, pressure-sensitive copying paper is based on the principle of which an electron donating and color-reactive, colorless organic substance for reaction with a Electron accepting substance in a medium of a non-polar oil solvent to form a color, the electron donating and color-reactive, essentially colorless organic substance (hereinafter referred to as "color former") leucomethylene blue, crystal violet lactone, Rhodamine-B-lactam and acidic rhodamine-B-sultone or the like. Comprises and the electrons absorbing substance acidic clay, active clay. Attapulgite, aluminum sulfate, natural zeolite. Kaolin, bentonite, silicon dioxide gel, feldspar, pyrophyllite, halloysite, magnesium trisilicate, zinc sulfate, Zinc sulfide, calcium fluoride, lead sulfate, lead sulfide and an organic acid such as calcium citrate, tannic acid and benzoic acid.

In general, a pressure-sensitive copier paper comprises a combination of a sheet containing the above-mentioned color former dissolved in a non-polar solvent such as benzene, toluene. Trichlorodiphenyl or the like, enclosed microcapsules as a coating on a paper and from a sheet which has the electron-accepting substance together with a binder as Bebebitzes, wherein R _{1 is} an alkyl group with 1 to 4 carbon atoms, R ₂ and R _{3 are} each a hydrogen atom , represent a halogen atom, a nitro group, an alkoxy group having 1 to 4 carbon atoms in the alkyl group, an alkoxycarbonyl group having 1 to 4 carbon atoms in the alkyl group, or an aldehyde group.
Preferably consists in the pressure sensitive

Copy paper the compound of 3-methylspiro- [benzothiazoline-2,2'-2'H- (l, 3) -benzoxazine], 3-methyl - 6 '- nitrospiro - [benzothiazoline - 2,2' - 2'H- (1.3) -benzoxazine], 3-methyl-6'-ni'ro-8'-formy! Spiro- [benzothiazoline - 2,2 '- 2Ή - (1,3) -benzoxazine], 3 - methyl - 6 ', 8' - dibutylspiro - [benzothiazoline - 2.2 '- 2' H-

(1,3) -benzoxazine] or 3-methyl-6'-nitro-8'-methoxyspiro- [benzothiazoline-2,2'-2'H- (1,3) -benzoxazine].

These compounds associate with an electron

absorbing substance with the formation of a distinctive color.

The above compound is dissolved in a solvent, e.g. B. benzene, toluene, dioctyl phthalate And chlorinated diphenyl od. The like., dissolved, encapsulated in microcapsules and as a coating on the Surface of paper applied.

In use, this material can be combined with a sheet such as those identified above Carries electron-accepting substance as a coating.

In addition, the microcapsules containing a solution of the above-described compound contained, and the electron accepting substance at the same time on the surface of the paper as a loading

layering can be applied. The microcapsules containing a solution of the color former can after Procedures as in U.S. Patent 2,800,457 and British Patents 1,091,076, 1,091,077 and 1,091,078.

The compound represented by the above general formula is usually referred to as "the following Working method produced:

2-aminobenzothiazole and a halogenated, lower one Alkyl or p-toluenesulfonic acid alkyl esters are implemented in an equimolar ratio. The quariernary salt thus obtained and an equimolar amount of one Salicylaldehyde derivative can be taken in ethanol in the presence of an equimolar amount of triethylamine Refluxing to give a compound of the formula given above.

The above-described reaction is illustrated by the following reaction equations ".

130 C, / V ^s

2 to 3 hours

NH,

-p-Ts

CHO

NAt ₃

AtOH

The compound thus obtained has sufficiently excellent properties as a compound for one pressure sensitive copier paper that forms a red to reddish-purple color on contact with the electron accepting substance is capable.

When producing pressure-sensitive copier paper, the connection is made together with a common color former, for example crystal violet lactone or benzoylleucomethylene blue. in Microcapsules encapsulated, creating different shades or colors, e.g. B. black, can be obtained, when the mixture of color formers is brought into contact with the electron accepting substance will.

The invention is explained in more detail below with the aid of examples.

example 1

3.4 g of S-methyl-I-aminobenzothiazolium-p-loluenesulfonate and 1.2 g of salicylaldehyde were dissolved in 25 ml of ethanol, and 1 g of triethylamine was added, followed by reflux for about 3 hours. It was then left to stand Bring crystals to crystallize, which were then filtered off and recrystallized from ethanol. There were 1.4 g of 3-methyl-spiro- [benzoihiazolin-2.2'-2'H- (1.3) -benzoxazine] obtained in the form of white crystals. The melting point of this compound was 155 to 159 C.

Elemental analysis:

Calculated ... C 67.38. H 4.21. N 9.9 ¹¹ O:
found C 67.15. H 4.51. N 10.44%.

ίο The solution of this compound in benzene was in Microcapsules enclosed and applied to the surface of paper as a coating, this Paper was then combined with a construction paper, the surface of which was acidic white clay and a

ι? Binder was coated. on what this material was pressed or printed by means of a typewriter. The pressed part instantly turned red colored.

B e i s ρ i e 1 2

3.4 g of S-methyl ^ -aminobenzothiazolium p-toluenesulfonate and 1.7 g of 5-nitrosalicylaldehyde were dissolved in 25 ml of ethanol and 1 g of triethylamine was added, followed by refluxing for about 3 hours. After 2.5 hours from the start of the reaction, yellow crystals crystallized out. After standing, the crystals were filtered and recrystallized from benzene, whereby 2.3 g of 3-methyl-6'-nitrospiro- [benzothiazoline-2.2'-2'H- (1,3) -benzoxazine] were obtained in the form of light yellow crystals . The melting point of this compound was 195 to 198 ° C.
Elemental analysis:

Calculated ... C 57.76, H 3.85, N 13.90%;

found .... C 57.51, H 3.54. N 13.42%.

When pressing this Verbirdung in the same manner as described in Example 1, the pressed Partly colored red-violet.

Example 3

3.4 g of 3-methyl-2-aminobenzothiazolium p-toluenesulfonate and 2 g of 3-formyl-5-nitrosalicylaldehyde were dissolved in 25 ml of ethanol and 1 g of triethylamine was added, followed by refluxing for about 3 hours. When the reaction liquid was concentrated to about a quarter and then cooled, orange colored crystals crystallized out. The crystals were filtered and recrystallized from ethanol, giving 2.1 g of S-methyl-6'-nitro-S-formylspiro - [benzothiazolium - 2,2 '- 2' H - (1,3) - benzoxazine] in the form of yellow crystals. The melting point of this compound was 162-165 ° C.

Elemental analysis:

Calculated ... C 55.92, H 3.66, N 12.90%;
found .... C 56.31, H 3.25, N 12.31%.

When using this connection for writing while applying pressure in the same way as in Example 1 given, the pressed part was colored red-violet.

Example 4

3.4 g of 3-methyl-2-aminobenzothiazolium p-toluenesulfonate and 2.8 g of 3,5-dibromosalicylaldehyde were added dissolved in 25 ml of ethanol, and 1 g of triethylamine was added, whereupon for 3 hours under reflux

was held, and if left to stand after reaction white crystals crystallized out. These were filtered and mixed from a Solution of ethanol and benzene recrystallized, whereby 3.3 g of 3-methyl-6'.8'-dibromspiro- [benzothiazoiin-2.2'-2'H- (1.3) -benzoxazine] in the form of white crystals. The melting point of this compound was 192 to 194 C.

When the solution of this compound in chlorinated diphenyl on the surface of the paper as a coating was applied and then placed on the surface of the clay paper and pressed the two papers the pressed part was instantly colored red.

Example 5

1.7 g of 3-methyl-2-aminobenzothiazolium-p-toluenesulfonate and 3-methoxy-5-nitrosalicylaldehyde were dissolved in 20 ml of ethanol, and 0.5 g of triethylamine were added and refluxed for about 2 hours. When cooling after the reaction, yellow-brown crystals crystallized out. These were filtered and recrystallized from ethanol, giving 1.2 g of 3-methyl-6'-nitro-8'-methoxyspiro- [benzothiazoline-2,2'-2'H- (1,3) -benzoxazine] in the form of pale yellow crystals were obtained. The melting point of this compound was 195 to 198 ^C C.

Elemental analysis:

Calculated ... C 56.20, H 4.08. N 12.51%;
found .... C, 55.98. H 3.82. N 12.24%.

Example 6

10 a of a 1 "own solution of the connection, which as in Example 2 ^ was obtained in chlorinated diphenyl, were added to 100 g of an aqueous solution of 10 "o'-methylcellulose, whereupon the mixture was stirred vigorously to obtain an emulsion. Afterwards this emulsion was coated onto the surface of the paper applied and dried. The thickness of the coating layer was 80 u.

When "the color-producing paper is placed on a construction paper and by the pressure of a writing instrument in in the same way as described in Example 1, pressed was, the pressed part was instantly colored red

Example 7

The paper made with that obtained in Example 5

Compound coated on its surface and in

in the same way as in Example 6

was, after hanging up, on a construction paper and Presses colored red.

Example 8

The compound contained in Example 4 was prepared according to that described in Japanese Patent No. 493,064 Encapsulated mode of operation. This capsule solution was applied as a coating to a paper surface and dried. When the color forming paper thus obtained is placed on a construction paper and printed was, the pressed or pressed part was instantly colored red.

Claims (1)

Patent claims: 1. Pressure sensitive copier paper that uses a carrier has a coating of microcapsules which contain a compound with results in a color reaction of an electron accepting substance, characterized in that that the compound has the general formula