DE3044036C2 - White writing fluid - Google Patents

Description

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The invention relates to a white writing fluid with at least one plastic used as a whitening agent and at least one swelling agent which swells the plastic.

DE-PS 17 94 303 is a white writing fluid Serving aqueous alkaline dispersion of styrene copolymer removable. An agent which swells the polymers is added to this aqueous dispersion. This writing fluid has the advantage that it does not contain any white pigments that result from the Dispersion could settle, so that the writing fluid can also be used for fiber pens, etc. Disadvantageous is, however, the long dryness of the writing fluid due to the high water content. Because the smear only becomes visible as the water evaporates, it takes a relatively long time for this smear to become visible will. Also, the smear is gray and translucent.

The same night Elle are recorded at a writing fluid according to DE-PS 15 19 437, where likewise ^b0 if an aqueous dispersion is present time on the basis of acrylic acid ester, methacrylic acid ester or styrene.

The white inks according to the JP-PS 51 22 428 and JP-PS 47 23 091 consist of itaconic acid in methanol and water from a solution of ^poly-h "'mers. Drying of this ink occurs due to the high water content is also very slow. The polymer crystallizes

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here from.

The white ballpoint pen paste according to JP-PS 49 23 861 consists of a polycarbonate that is dissolved in chloroform is dissolved as a low boiling point solvent and polyalcohol as a high boiling point solvent. The use of chloroform here is questionable. By using two different solvents At the boiling point, problems arise, in particular, in manufacture as well as in use there are different white effects depending on the age of the ballpoint pens filled with the paste.

The object is therefore to create a white writing fluid which has a high whiteness effect and dries quickly.

This object is achieved with the characterizing features of claim 1. Advantageous embodiments can be found in the subclaims.

By using a non-aqueous dispersion of plastic and swelling agent and by using it an evaporable acetic acid ester as a swelling agent ensures that the smear dries quickly and becomes visible. A non-aqueous dispersion using a rapidly evaporating acetic acid ester is not suggested by the prior art. By using PVC or a vinyl chloride / vinyl acetal copolymer or a urea-formaldehyde polymer is achieved that the smear has a high whitening effect. These substances are in Acetic acid ester is stably dispersible and is not suggested as a whitening agent by the prior art. the Writing fluid can easily be used in writing implements whose writing head has fine cannulas, without the whitening agent clogging the cannulas. By swelling the plastic by means of of an acetic acid ester, a dispersion is obtained which, in a certain sense, has a gel-like character. A Settling of the plastic from the dispersion cannot be observed.

The implementation options are shown below using examples of the above invention explained.

example 1

Acetic acid n-butyl ester
Suspension PVC
Styrene bead polymer
optical brightener

72.0 %

22.0 96

6.0 96

0.0296

The acetic acid ester acts as a swelling agent and solvent. The PVC represents the whitening agent Styrene bead polymer is a film-forming resin that is soluble in the ester.

Example 2

Propyl acetate
Vinylchlorld / vinyl acetate copolymer
Styrene bead polymer
optical brightener

72.0 %

22.0 96 6.0 96 0.02%

In this example represents the vinyl chloride / vinyl acetate copolymer the whitener.

Example 3

Acetic acid propy lesler
Ethyl acetate
2-chlorobenzoic acid
Suspenslons-PVC
optical brightener

48.8 %

19.5%

14.6 9t, 17.1 9b

0.0296

The 2-chi.benzoic acid gives a white when smeared

Crystallization product. This example represents a particularly economical solution.

Example 4

Ethyl acetate 40.0 %

Amyl acetate 20.0 %

Vinyl chloride / vinyl acetate

Copolymer ^, 5 96

2-chlorobenzoic acid 14.5 %

optical brightener 0.02 *

Example 5

Butyl acetate 57.0 %

Ethyl acetate 14.0 96

Suspension PVC 22.0 %

Tetraisopropyl titaviate 7.0 96

optical brightener 0.02%

Tetraisopropylitanate is an organometallic compound which is soluble in the swelling agent or solvent, which

forms an insoluble hydrolysis product after the swelling agent has evaporated.

Example 6

Butyl acetate

Ethyl acetate

2-chlorobenzoic acid

Suspension PVC

Tetraisopropyl titanate

optical brightener

49.0%

12.0%

12.0%

25.0 %

0.02%

This example produces optimal white effects.

Example 7

Propyl acetate

Ethyl acetate

2-chlorobenzoic acid

Suspension PVC

Urea-formaldehyii-

polymers

optical brighteners

44.0 %

17.0 %

14.0 96

15.0%

10.0% 0.02%

All of the smears in the above examples can be removed from their base and can be slightly damp be wiped off.

Claims (4)

Patent claims: 1. White writing fluid with a plastic serving as a whitening agent and at least one swelling agent swelling the plastic, characterized in that it consists of (a) 50 to 80% by weight of evaporable acetic acid ester as swelling and solvent, (b) 10 to 25% by weight PVC and / or a vinyl chloride / vinyl acetate copolymer and / or urea-formaldehyde polymer as a polymer whitening agent, (c) 0 to 15% by weight of benzoic acid or chlorobenzoic acid acid as a crystallizing whitening agent, (d) Obis lOGew.- «Tetraisopropyl titanate, as hy- drolyzing whitener, (e) Obis 6% by weight of styrene bead polymer as a film former as well
(0 usual amounts of optical brighteners. 2. White writing fluid according to claim 1, -'5, characterized in that the swelling agent (a) Ethyl acetate and / or butyl acetate and / or propyl acetate and / or amyl acetate is. 3. White writing fluid according to claim 1, Jo, characterized in that the chlorobenzoic acid (c) is 2-chlorobenzoic acid. 4. White writing fluid according to claim 1, characterized in that the plastic (b) and the benzoic acid (c) are present in approximately equal proportions of ^ approximately 15%. 20th