FI57071B - ARK FOER ANVAENDNING I ETT TRYCKKAENSLIGT KOPIERINGSSYSTEM - Google Patents

Description

RSSFH [B] (11) ™ RELEASE 57071 ffiA l J U; UTLÄGGNINGSSKRIFT ^ (45) Pa ton t e-.iriplnt ^ ^ (51) Kv.lk. * / Lnt.CI. * B 41 M 5/12 FINLAND — FINLAND (21) p * t «n« lh »k» mu · -p »« »t» eiaiin * 2578/72 (22) HakamitpUvi - An * eknlnpda «19 * 09-72 (FI) (23) ANuiplivl — GlltlghMadag 19-09-72 (41) Tullut | offantllg 2k. 03-73

Pttwttl I »r.klttwIhalHtui νκολ, ιρ ™. J.I..LMU »,

Patent · ocn regitteratyrelsen 'An * ek »n uti ** d och uti ^ krifUn pubikend 29-02.συ (32) (33) (31) Pyydetty muoNcmi — B« gtrd prtoritet 23-09-71 20.01.72, 06.09 -72 Englaiiti-England (GB) I + 4U7I + / 7I * 2785/72, 2785/72 (71) Wiggins Teape Research & Development Limited, Gateway House, 1 Watling Street, London ECI +, England-England (GB) (72) ) John Edward Ross, Stoke Poges, Buckinghamshire, David James Marshall,

High Wycombe, Buckinghamshire, Brian Samuel Chapman, Prestwood,

Buckinghamshire, England-England (GB) (7 * 0 Oy Kolster Ab (5¾) Sheet used in the pressure-sensitive copying method - Ark för använd-Ning i ett tryckkänsligt kopieringssystem

The invention relates to a sheet for use in a pressure-sensitive copying process comprising a base sheet coated with microcapsules each containing an organic, initially colorless color former, for example crystal violet-lactone, benzoyl-leukomethylene-blue, 3,3-bis (dialkyl) dialkyl 3-Dialkylamino-6-alkyl-β-alkylamino-fluorane or 3-dialkylamino-7-dialkylamino-fluorane dissolved in a solvent. The pressure-sensitive copying method may be of the type in which the microencapsulated coating is on one side of a transfer sheet, which is called a CB sheet (background coated) and the reactive antibody is applied to the other side of the recording sheet, this is called a CF sheet (front side coated), or be of the self-developing type, with the microcapsules and the reactive antibody on the same side of the same simple sheet. Methods with a high number of copies use intermediate CFB sheets (back and front coated).

In known CB sheets, the microcapsules of the microcapsule coating may be separate or may form capsule groups. The walls of each microcapsule are made of a hydrophilic colloidal substance, such as gelatin, and contain a color-forming agent (color former) having basic chemical properties: 2 57071 which, in use, comes into contact and stains with an antibody, such as attapulgite clay, with particles of acid-treated montmorillonite clay or an acidic phenolic polymeric substance of an oil solution (usually in combination with kaolin clay) on the surface of the CF sheet to give distinct colored markings on the surface of the CF sheet. Such contact and staining is obtained by breaking microcapsules at the local compression caused by writing by hand or by machine or uncoated printing on the front of the CB sheet was coated with the back side being in contact with a CF sheet coated with the front side.

Various methods for making microcapsules and capsule units are well known, as are various methods for coating a core sheet with microcapsules and capsule units into a CB sheet and methods for coating a base sheet with a reactive antibody into a CF sheet, and therefore such methods are not described in detail herein.

Normally, the phase inside the microcapsule, i.e. the substance inside the walls of the microcapsule, contains one or more colorants of a coloring nature, typically crystal violet lactone (CVL) and benzoyl-leucomethylene blue (BD4B) or 3,3-bis (dialkyl-indyl). ) phthalides, 3-dialkylamino-6-alkyl-7-alkylaminofluoranes. These color formers are dissolved in a solvent, typically hydrogenated terphenyl or monoisopropyl-biphenyl, and diluted with e.g. fuel oil. The dyes CVL and BLMB are normally used together because CVL is able to stain rapidly and BLMB is able to provide permanent staining when reacted with commonly used reactive antibodies such as those listed above.

There are various tests used to compare weight-sensitive copying methods, and these are the most important "calendar" intensity test (CI) and the staining test. Other tests used include fading tests for window fading and office fading, and a rice fading test. All of these tests are well known and are therefore not described in detail here. Suffice it to say that the CI test is a measure of the strength of the imprint, which means the clarity of the imprint formed, and the result is expressed as a percentage, the lower the percentage the better the print intensity, and the staining test is a measure of the resistance of the CB sheet to random less than 100, the higher the number the better the resistance of the CB sheet to accidental rupture of the microcapsules. The window fading test and the office fading test measure the intensity of the print after exposure to daylight and artificial light for different lengths of time, while the rice deterioration test measures the original print intensity obtained on sheets stored for different lengths of time.

3 57071

Three other important factors to consider when comparing weight-sensitive copying methods are odor both before and after manufacture, toxicity and price.

In particular, this invention relates to the internal phase in microcapsules used in weight-sensitive copying methods of the type defined above.

According to the invention, a sheet used in weight-sensitive copying processes of the type defined above comprises a base sheet coated with microcapsules, each capsule containing an organic, initially colorless color former dissolved in a solvent containing dibenzylbenzenes of the general formula * - J-ch2 4 - «" 24 - | - * 6 HB \ R2 3 5 in which R1-R8 represent hydrogen, alkyl groups containing less than 5 carbon atoms or aralkyl groups containing 7 or 8 carbon atoms.

Preferably, the solvent contains a mixture of these dibenzylbenzenes in which R 1 -R represent hydrogen or lower alkyl groups having less than 3 "carbon atoms.

1 6

The preferred solvent contains a mixture of these dibenzylbenzenes wherein R -R represent hydrogen and methyl groups up to 3. Preferably, the mixture of dibenzyl-1-benzenes contains by weight:

Dibentsyylibentseenejä! n. 10 - 15

Methyldibenzylbenzenes: about 40 i »(including dibenzyltoluene)

Dimethyldibenzylbenzenes: about 35-40 $ 6

Trimethyldibenzylbenzenes: about 10 to about 99 with the remainder being impurities of higher molecular weight.

Such a mixture is sold in the United Kingdom under the trade name Lipinol T Huls (U.K.) Ldt. The level of toxicity of Lipinol T is very low in various mammals, with a lethal dose of more than 20 g / kg. Thus, Lipinol T does not pose a risk of toxicity to humans under normal conditions when used as a solvent in the inner phase of microcapsules of a weight-sensitive copying method.

4,57071

Compared to other solvents, the preferred mixture of dibentayylbenzenes has the following advantages: cheapness, better initial intensity of CB sheet coating weight given to the ice sheet (Cites ti) when used with CF sheet with oil-soluble, acidic phenolic polymeric agent / kaolin clay coating: , which allows high dilution; slower decay value window-fade test path; less odor both during manufacture and in the finished CB sheet. Still, the preferred mixture has no adverse effects on office-fade-rice-deterioration tests.

The preferred mixture of dibenzylbenzenes has a viscosity of between 35-45 ° C at 20 ° C and a density of 1.0-1.04 g / ml; road travel range 2700 Pa 240-26 ° C and a flash point at about 160 ° C.

Experiments have shown that a preferred mixture of dibenzylbenzenes dissolves 8.3% w / v. 0Lt and 3.8 w / v. BLNB and that it is fully compatible with fuel oil, which is a standard and inexpensive diluent.

The preferred mixture of dibenzylbenzenes is a suitable solvent for many other color formers used in weight-sensitive copying processes, and in particular for 313-bis (dialkylindolyl) phthalides, 3-dialkylamino-6-alkyl-7-alkylamino-fluoranes and 3-dialkylamino-dialkylamino -fluoraanit.

Embodiments specific to the invention are described below by comparing the results with the test results provided by a CB sheet made in a pilot plant.

Example 1

A reference CB sheet was prepared by coating microcapsules containing a standard inner phase with hydrogenated terphenyl as solvent, fuel oil as diluent, and both CVL and BLHB as color formers, a base sheet with a coating thickness of about 6.3 g / m 2. The solvent to diluent ratio was 4: 1 w / w.

Similar microcapsules, except that they contained as a solvent a mixture of dibenzylbenzenes sold under the name Lipinol T, and a solvent / diluent ratio of 1: 1 w / w, were prepared in the same manner and coated on a base sheet with a coating weight of about 6.3 g / m .

According to Huls (U.K.) Ltd, the composition of Lipinol T is as follows:

Compound

Bibentylbenzenes approx. 10 - 15 #

Methyl dibenzylbenzenes approx. 40%

Bimethyldibenzylbenzenes about 33-40

Trimethyldibenzylbenzenes 10%

Benzyl anthracene and other korn.

condensable substances 1 # 5 57071

The raw material characteristics for each CB sheet produced, calculated in pence / ml, which is a cost item for coating the base sheet with an equal number of microcapsules, were:

Reference sheet - 0.02401 p / ml

Sheet of the invention - 0.01890 p / ml

The reference sheet and the sheet of the invention were then examined by the "calendar intensity" test with three different CF sheets, namely the attapulgite-Vella coated sheet (ACTA CF); acid treated with montmorillonite clay / kaolin clay coated sheet (S / K); and phenol-polymeric substance / kaolin clay coated sheet (P / K CF). The results were as follows:

ACTA CF S / K CF P / K CF

Comparison CB CI 65 Oi 71 CI 75

CB CI 61 CI 67 CI 63 of the Invention It can be seen from these results that the CB sheet according to the invention gave a better initial print imprint intensity in each case and in particular with P / K CF.

Example 2

Similar reference and CB sheets of the invention were prepared except that the coating weight was 6 g / m 2 and these sheets were examined by window-fade, function to-fade and rice deterioration tests. The results are shown in the following tables: 6 57071

Ikkuna-Haalis tuxnis tes ti

ACTA CF S / K CF P / K CF

Comparison Of The Invention Comparison Of The Invention Comparison Of The Invention

03 CD CD CD. CD CD

Origin.Cl -65 61 71 67 75 63 2 days 79 75 .71 G8 .86. 83 5 days 84 84 75 75 '91 90> 1 week 90 87 79 77 94 93 • 2 weeks 94 88 84 77 98 97 3 weeks P 95 87 86 75 99 98 \ * 'Office Fading Test;

ACTA CF S / K CF P / K CF

Comparison Of The Invention Comparison Of The Invention Comparison Of The Invention ______ CB CB CB CB__OB__OB__

Alkuper.Cl 65 61 71 67 .75 63 2 days 64 60 66 62 69 65 1 week 67 63 68 65 69 64 2 weeks 69 65 69 67 72 71 3 weeks 70 ‘66 71 68 74 75

Rice Deterioration Test ACTA CF S / K CF "" J P / K CF 1

Comparison of the Invention Comparison of the Invention Comparison of the Invention OB CB OB CB CB OB

Origin.Cl 65 61 71 67 75 63 2 weeks G6 63 71 67 74 C2 * 4 weeks 64 62 71 ’CC 73 62

Claims (1)

57071 7 While the above embodiments of the invention all use a mixture of dibenzylbenzenes sold as Lipinol T, wherein the substituents R -R in the above general formula represent hydrogen 16 or methyl groups up to three, it is also possible to use mixtures of these dibenzylbenzenes in which R -R represent hydrogen, alkyl groups containing less than 5 carbon atoms, and aralkyl groups containing 7-Θ carbon atoms. Preferably, however, R 1 and R 2 represent hydrogen and lower alkyl groups having less than 3 carbon atoms. Claim: A sheet for use in a pressure-sensitive copying process comprising a base sheet coated with microcapsules each containing an organic, initially colorless color former, for example crystalline lactone, benzoyl-leucomethylene blue, 3,3-bis (dialkyl) dialkyl , 3-dialkylamino-6-alkyl-7-alkylamino-fluorane or 3-dialkylamino-7-dialkylamino-fluorane dissolved in a solvent, characterized in that the solvent contains dibenzylbenzene of the general formula: R 2 R 3 R 6 in which R -) hydrogen, alkyl groups containing less than 5 carbon atoms, or aralkyl groups having 7 or 8 carbon atoms.