Record material
Abstract
A thermally sensitive record medium is disclosed. Data is generated on the record medium in response to an application of heat. The record medium is capable of generating data images in more than one color by exposing the medium to more than one temperature level in areas to be imaged. Overlap or interference between two colors is avoided by utilizing at least one color-forming system which requires a thermal decomposition of one system component before it can be reacted to yield color.

Term
No projected expiry on record.
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17 claims: 5 independent, 12 dependent
- 1Patentkrav 1. Termiskt känsligt uppteckningsmaterial bestående av ett bärarark uppbärande en termiskt svarande komposition, vilken innehåller ett första färgbildande system, bestående av en färgbildare och en samreaktant, med förmågan att ge färg vid eller över en temperatur och ett andra färgbildande· system med förmågan att ge färg vid eller över en högre temperatur, känneteckna t av att det andra färgbildande systemet består av en föregångare och en samreaktant, varvid föregångaren har den egenskapen, att den kan termiskt sönderdelas till en färgbildare, vilken därefter kan reagera med samreaktanten under bildning av en färg och att sönderdelningen sker vid en högre temperatur än den vid vilken färg bildas av det första färgbildande systemet.
- 2Uppteckningsmaterial enligt krav 1, kännetecknat av att det första färgbildande systemet utnyttjar en färgbildare och en samreaktant, vilken är densamma eller skild från den som utnyttjas i det andra färgbildande systemet, varvid den ena av färgbildarna och samreaktanten har förmågan att smälta eller förångas, så att de reagerar med varandra och därvid ger en färg.
- 3Uppteckningsmaterial enligt krav 2, kännetecknat av att den första färgbildaren i det första färgbildande systemet utgöres av 3,3-bis(l-etyl-2-metylindol)-3-yl)ftalid;3,3-bis(4-dimetylaminofenyl)-6-dimetylarainoftalid;2'-bromo-3'-metyl-6'dietyl-aminofluoran eller 2'-butoxi-6'-dietylaminofluoran.
- 4Uppteckningsmaterial enligt krav 2 eller 3, kännetecknat av att samreaktanten i det första färgbildande systemet utgöres av 4,4'-i-propylidendifenol eller 4,4 , '-tiodifenol.
- 5Uppteckningsmaterial enligt något av föregående krav, kännetecknat av att föregångaren är en tioamid med formeln (I) . 7812551 - (I) där R^ betecknar en alkylgrupp, en arylgrupp lämpligen substituerad med en halogenantom, en biarylgrupp, en aralkylgrupp, en alkyloxigrupp, en aryloxigrupp, en aroylgrupp, en aryloxialkylgrupp eller en grupp H_NCS(CH_) -, i vilken n betecknar från 1 till 2 3 z z n12
- 66 och R och R betecknar en väteatom, där R och R betecknar en arylgrupp och R betecknar väteatom eller där R betecknar en alkylgrupp, R betecknar gruppen ~(CH_) NHCS-R , i vilken R betecknar en alkylgrupp och i vilken n betecknar från 1 till 6 och där R betecknar en väteatom, varvid alkylgrupperna innehåller 1-4 kolatomer, arylgruppen företrädesvis utgöres av en fenylgrupp, halogenatomen företrädesvis utgöres av klor och aroyIgruppen företrädesvis utgöres av benzoyl och där n företrädesvis betecknar från 3 till 6. 6. Uppteckningsmaterial enligt krav 5, kännetecknat av att tioamiden är tioadipamid.
- 7Uppteckningsmaterial enligt något av kraven 5 och 6, kännetecknat av att samreaktanten i det andra färgbildande systemet utgöres av en metallisk samreaktant i vilken katjonen är åtminstone divalent.
- 8Uppteckningsmaterial enligt krav 7, kännetecknat av att katjonen utgöres av en nickel, järn, bly, kvicksilver, koppar eller koboltkatjon.
- 9Uppteckningsmaterial enligt något av kraven 7 eller 8, k ä n netecknat av att den metalliska samreaktanten utgöres av nickelacetonylacetonat eller nickelnaftenat. '7812551-5
- 10Uppteckningsmaterial enligt något av kraven 1-4, kännetecknat av att föregångaren utgöres av en spiropyran med formeln (II) C £ där R och R är lika eller olika och var och en utgöres av en 7 alkylgrupp med 1-4 kolatomer eller en fenylgrupp, där R betecknar väte eller en halogen eller en alkoxigrupp eller alkylgrupp O med 1-4 kolatomer, där R betecknar en alkoxigrupp med 1-4 kolq i n atomer, där R och R är lika eller olika och betecknar väte eller halogen och där R^ betecknar en alkoxigrupp med 1-4 kolatomer eller väte.
- 11Uppteckningsmaterial enligt krav 10, kännetecknat av att spiropyranen är 4'-(l,3,3-trimetylindolenyl)-6'-kloro8'-metoxi-l,3,3-trimetylbenzoindolinospiropyran;4- (1,3,3 trimetylindolenyl)-6'-kloro-8'-etoxi-l,3,3-trimetylbenzoidolinospiropyran;4'-(1,3,3-trimetylindolenyl)-8'-metoxi-l,3,3-trimetylbenzoindolinospiropyran eller 4'-(1,3,3-trimetylindolenyl)8'-etoxi-l,3,3-trimetylbenzoindolinospiropyran.
- 12Uppteckningsmaterial enligt något av kraven 10 och 11, kännetecknat av att samreaktanten i det andra färgbildande systemet utgöres av en fenolförening.
- 13Uppteckningsmaterial enligt krav 12, kännetecknat av att fenolen utgöres av 4,4'-i-propylidendifenol eller 4,4'tiodifenol. 7812551-5 3tA
- 14Uppteckningsmaterial enligt något av föregående krav, kännetecknat av att den termiskt känsliga kompositionen bildar en beläggning på ett bärarark som ett enda skikt med alla färgbildande systemen däri.
- 15Uppteckningsmaterial enligt krav 1, kännetecknat av att den termiskt känsliga kompositionen innehåller fler än två färgbildande system innefattande fler än en föregångare och att den ytterligare föregångaren skall ha en så- 10 dan sönderdelningstemperatur att den skiljer sig från den tidigare använda föregångaren och att systemet därigenom kan bilda ytterligare färger, skilda från de andra bildade färgerna och att den ytterligare föregångaren ej interfererar med de övriga färgbildande systemen.
- 16Förfarande för framställning av ett termiskt känsligt uppteckningsmaterial enligt krav 1,bestående av ett bärarark uppbärande en termiskt svarande komposition, vilken innehåller ett första färgbildande system, bestående av en färgbildare och
- 1720 en samreaktant, med förmågan att ge färg vid eller över en temperatur och ett andra färgbildande system med förmågan att ge färg vid eller över en högre temperatur, varvid det andra färgbildande systemet består av en föregångare och en samreaktant, varvid föregångaren har den egenskapen, att den kan termiskt 25 sönderdelas till en färgbildare, vilken därefter kan reagera med samreaktanten under bildning av en färg och att sönderdelningen sker vid en högre temperatur än den vid vilken färg bildas av det första färgbildande systemet, kännetecknat av att en dispersion i ett vattenhaltigt medel av de färgbildan30 de komponenterna i varje färgbildande system och ett termografiskt acceptabelt bindemedel framställes och att den erhållna dispersionen påföres bärararket och torkas. 7812551-5 \h-cs-nh-r 3 111 r 2/
Independent claims17
168 paragraphs in 8 sections, as filed
(24) Running day
Patent Office (62) National application number (86) International filing date (86) Filing date for European patent application (30) Priority information (11) <sup>number</sup> 443 535
79-06-16
12/12/06 Application received as:
78-12-06
H Swedish patent application completed international patent application with number converted European patent application with number
77-12-15 US 861046 (71) Applicant Appleton Papers Inc, Appleton Wis US (72) Inventor Η H. Baum, Appleton Wis (74) Agent H Albihns patent agency AB [54) Designation Thermally sensitive recording material consisting of a carrier sheet carrying two color-forming systems, one of which has a precursor: 56) Published publications: GB 1,401,639 (B41M 5/18), GB 1,463,815 (C09B 57/00) Other publications: Chemical Abstract's, vol.77 (1972) abstract no. 116 069y, JP 72 13427: 57) Summary:
Thermally sensitive recording material in two colors where one of the color forming systems cannot operate until a precursor to one of the participating materials is thermally decomposed to form said material. The decomposition temperature of the precursor is higher than the color-forming temperature of the second color-forming system.
Figures in brackets indicate international identification code, INID code Letters in clamps indicate international document code
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Thermally sensitive recording materials are well known and are described in many patents such as U.S. Patents Nos. 3,293,055, 3,445,261, 3,451,338, 3,539,375, and 3,674,535. Essentially, they consist of a carrier sheet coated with a thermally sensitive composition comprising a color forming agent. systems utilizing a colorant and a co-reagent. When the composition coating is heated by a suitable imaging tool, to normal thermographic temperatures, the co-reactant melts and / or evaporates and reacts with the color former to form a colored mark or image corresponding to the shape of the area of the coating heated.
In some applications involving data recording, it is often convenient to use a recording material having the ability to produce more than one color, whereby in this way the data can be presented, for example, in different colors on a sheet according to a predetermined color code. The sensitive composition contains more than one color forming system and depending on the temperature to which it is heated, one color or another color can be obtained. Japanese Patent Specification 4786269 discloses such recording materials wherein the thermally sensitive composition contains two color forming systems. The colorants are both fluorane compounds with very different melting points and the same co-reactant, a phenol compound used for both systems. The colors are generated by melting the co-reactant and subsequent mixing with the colorants. The first color is obtained at a low thermographic temperature from the fluorine compound with the lower melting point and the second color, a combination of the colors, is obtained at a higher thermographic temperature from both fluoros.
7812551-5 robbery associations. ' Depending on the resolution of the fluorane with the higher melting point in the melt of the other, there is an interference in forming one color with the development of the other, i.e., there is an overlapping coloration and no separation but a gradual color change is obtained between the two temperatures at which the fluorane compounds melts. This problem is made even more difficult by the presence of impurities in the fluorine melts.
Japanese Patent Application 48/53703 also discloses a two-color recording material, in which two color-forming systems are included in the thermally sensitive composition. The system operating at the lower thermographic temperature utilizes two colorants and a phenolic co-reactant, which upon melting or evaporation of the co-reactant reacts together to produce a color which is in reality a combination of two colors, each formed by each colorant. The system operating at the higher thermographic temperature, on the other hand, utilizes a decolorizing agent, such as a guanidine derivative, which acts on one of the two combined colors to a greater extent than the other, thereby causing a change in color. The effect of such decolorizing agents is not limited to either of the two combined colors and may further vary with temperature. As a result, no sharp color changes are obtained.
A further two-color recording material is disclosed in Japanese Patent Application 48/7003. This material comprises two color forming systems in a thermally sensitive composition. One system utilizes an acidic colorant and a basic co-reactant while the other utilizes a basic colorant and acidic co-reagent with a melting point that is widely different from that of the basic co-reactant.
At a lower thermographic temperature, the low-melting sam7812551-5 melts the reactant and reacts with the corresponding colorants to form color. At the higher thermographic temperature, the second co-reactant melts, neutralizes the first co-reactant, and decolors the color obtained at the lower thermographic temperature. It then reacts with the other colorant to form another color. Here too, a change from one color to another is not as sharp as desired.
It is, therefore, obvious that the multi-color recording material known above can suffer from the same problems to a greater or lesser extent. They form, in a given thermographic temperature range, gradually passing colors from the shades of the first to the shades of the second, thus no sharp color change is obtained.
Thus, it is an object of the present invention to provide a thermally sensitive recording material capable of providing more than one color, thereby providing a sharp color change.
The present invention provides a thermally sensitive recording material consisting of a carrier sheet carrying a thermally responsive composition which includes a first color forming system capable of providing color at or above a temperature and a second color forming system capable of providing color at or above a higher temperature. characterized in that the second color-forming system consists of a precursor and a co-reactant, the precursor having that property, that it can be thermally decomposed into a dye former, which can then react with the co-reactant to form a dye and that the decomposition occurs at a higher temperature than that at which dye is formed by the first dye-forming system.
Conveniently, in the first dye-forming system, a dye former and a co-reactant are used which are the same or different from the one used in the dye-forming systems.<sup>-</sup> the second color forming system, wherein one of the color forming agents and the co-reactant has the ability to melt or vaporize so that they react with each other, thereby giving a color.
The colorant used in the first color-forming system may be one or more compounds which are generally basic and which usually include a lactone ring, for example a phthalide or fluorane compound, or a mixture thereof. Specific types of such compounds include alkyl, phenyl, indole, pyrol, and carbazole-substituted phthalides (especially those disclosed in U.S. Pat. Nos. 3,491,111, 3,491,112, 3,491,116 and 3,509,174 and nitroamino, amido, , sulfonamido, aminobenzylidene, halogen and anilino-substituted fluoranes (especially those disclosed in U.S. Patent Nos. 3,624,107, 3,627,787, 3,641,011, 3,642,828, and 3,681,390). The most preferred color is crystal violet lactone 3,3-bis (4-dimethylaminophenyl) -6-dimethylaminophthalide; 6'-diethylamino-1 ', 2'-benzofluoran; 3,3-bis (1-ethyl-2-metylxndol-3-yl) phthalide; 6'-diethylamino-2'-anilino fluorane; 6'-diethylamino-2'-benzylaminofluorane; 6'-diethylamino-2 '-butoxy fluorane and 6'-diethylamino-2'-bromo-3'-methylfluorane.
The co-reactants for use with the first dye-forming system and the second dye-forming system may be the same or different, the choice of co-reactant being mainly dependent on its efficiency in the reaction with the dye-forming agent in the first or second system to form the desired dye or color change. Generally, the co-reactant is an acidic material, such as a mono- or diphenol, including those described in U.S. Patent 3,451,338. Particularly preferred is 4-t-butylphenol;
4-phenylphenol; 4-hydroxidifenyloxid; a-naphthol; β-naphthol; metyl7812551-5
4-hydroxybenzoate; 4-hydroxyacetophenone; 4-t-octylcatechol; 2,2'-dihydroxydiphenyl; 2,2'-methylene-bis (4-chlorophenyl); 2,2'-methylenebis (4-methyl-6-t-butylphenol); 4,4'-in-propylidendifenol; 4,4'-i-propylidene-bi s- (2-chlorophenol); 4,4'-i-propylidene-bis- (2,6-dibromophenyl); 4,4'-i-propylidene-bis (2,6-dichlorophenol); Ipropyliden 4,4'-bis (2-methylphenol); 4,4'-i-propylidene-bis (2,6-dimethylphenol); 4,4'-i-propylidene-bis (2-t-butylphenol); 4,4'-p-butylidenbis- (2-methylphenol); 4,4'-cyklohexylidenfenol; 4,4'-cyclohexylidene-bis (2-methylphenol); 2,2'-thio-bis- (4,6-dichlorophenol) and 4,4'-thio-diphenol.
Although not preferred, other acidic materials can be used as co-reactants of the present invention. Examples of such other materials include phenolic novolac resins which are a product of a reaction between, for example, formaldehyde and a phenol such as an alkyl phenol, e.g. p-octylphenol or another phenol such as p-phenylphenol. Acidic mineral materials are also included, such as colloidal silica, kaolin, bentonite, attopulgite, halloysite and the like. Some of these resins and minerals do not melt or vaporize within normal thermographic temperature ranges, but may still react with the colorants as a result of melting or vaporization of the latter within such ranges.
Alternatively, a metallic co-reactant may be used in which case the cation is preferably at least divalent, such as a cation of nickel, iron, lead, mercury, copper cobalt, manganese, zinc, aluminum, magnesium, calcium, strontium and the like. The anion used with the cation is only significant as long as it results in the co-reactant reaching a melting point within the normal thermographic temperature range and to the extent that it enables the cation for the color former to be available. Examples of
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<img file="SE443535B_D0001.tif" />
Suitable anions include resinate, naphthenate, stearate, oleate, acetylacetonate, acetate, undecylenate, ricinolate and the like.
The precursor may be one of two types, although it may be noted that the present invention is not limited thereto. Thus, it may be a substituted thioamide which forms hydrogen sulphide, the colorant, at its decomposition temperature. Such thioamides can be represented by the following formula:
<img file="SE443535B_D0002.tif" />
(I) where r! represents an alkyl group, an aryl group suitably substituted with a halogen atom, a biaryl group, an aralkyl group, an alkyloxy group, an aryloxy group, an aroyl group, an aryloxyalkyl group, or a group HN.CS. (CH 2) - where n represents 1.2,<sup>Z</sup> 3
3,4,5 or 6 and wherein R and R are a hydrogen atom; or 123
R and R are an aryl group and R is a hydrogen atom or where R is an alkyl group, R is a group
-CH<sub>9</sub>) In which R-represents an alkyl group, where n represents π 2 represents 1,2,3,4,5 or 6 and wherein R represents a hydrogen atom. The alkyl groups preferably contain from 1-4 carbon atoms and are, for example, methyl or ethyl. The aryl groups are a phenyl group and the halogen atom represents chlorine; the aroyl group represents benzoyl and n represents 3,4,5 or 6.
Particularly preferred examples of such thioamides are set forth below with their respective decomposition temperatures.
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T ioamide precursors
Decomposition temperature (° C)
1st Tioazelamid
2nd Tioadipamid
3rd Difenyltioacetamid
4th Bifenyltioacetamid
5th £ -klorofenyltioacetamid
6th Benzoyltioacetamid
7th Tetrametylenditiopropionamid
Eighth Fenoxitiopropionamid
138-141
187-190
151-153
170-174
126-129
128-130
119-121
91-93
A precursor which, at decomposition temperature, forms hydrogen sulfide as a color former, is to be used with a co-reactant which is a metallic co-reactant. Thereby, a very dark staining is obtained as a result of the formation of a metal sulfide. Examples of metallic co-reactants have been mentioned previously.
Alternatively, a second type of precursor may be a reaction-blocked benzoindolinospiropyran, which decomposes at its decomposition temperature in the desired colorant, a benzoindolinospiropyran and a by-product derived from the blocking group. Generally, the blocking group is attached to the 4 'carbon atom and is an indolenyl group in which case the precursor is a so-called dichondensed benzoindolinospiropyran compound. Examples of spiropyran colorants which can be blocked in 4 'position with an indolenyl group include those disclosed in U.S. Pat. Nos. 3,293,055 and 3,451,338. However, the present invention provides a new and preferred type of spiropyran precursor represented by the general formula:
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Formula II
<img file="SE443535B_D0003.tif" />
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6 wherein R and R are the same or different and each is an alkyl group of 1-4 carbon atoms, preferably a methyl group or a phenyl group, where R? represents hydrogen or halogen or an alkoxy or alkyl group of 1-4 carbon atoms, where R represents an alkoxy group of 1-4 carbon atoms where R 1 and R are the same or different and represent hydrogen or halogen, preferably chlorine and where R an alkoxy group having 1-4 carbon atoms or hydrogen.
Examples of specific compounds which fall within the scope of formula (II) are: 4 '- (1-phenyl-3,3' -dimethylindolenyl) -8'-methoxy
1-phenyl-3,3-dimetylbenzoindolinospiropyran; 4 '- (1,3-trimetylindolenyl) -5'-chloro-8'-methoxy-1,3,3-trimetylbenzoindolinospiropyran; 4 '- (1,3,3-trimethylindolenyl) -5', 6'-dichloro-8'-methoxy;
1,3,3-trimethylbenzoindolinospiropyran and 4 '- (1,3,3-trimethylindolenyl) -4,7,8'-trimethoxybenzoindolinospiropyran.
The most preferred reaction-blocked spiropyran precursors are listed below together with their respective decomposition temperature.
Spiropyran Predecessors
1st 4 '- (1,3,3-trimethylindolenyl) -6'-chloro-8'-ethoxy-1,3,3-trimethyl-benzoindolinospiropyran
2nd 4 '- (1,3,3-trimethylindolenyl) -6' -chloro-8<sup>1</sup>-methoxy-1,3,3-trimethyl-benzoindolinospiropyran
3rd 4 '- (l, 3,3-trimetylindolenyl) -8'-methoxy-1,3,3, trimethyl-benzoindolino-spiropyran
Decomposition temperature (° C)
205-207
204-206
208-210
7812551-5 ίο
4th 4 '- (1,3,3-trimethylindole-200-202-enyl) -8'-ethoxy-1,3,3-trimethylbenzoindolino-spiropyran
A spiropyran precursor which at its decomposition temperature forms the corresponding spiropyran as the colored form, is preferably used with a phenolic co-reactant of the type previously mentioned.
The preparation of the substituted thioamide precursors is well known. The preparation of the dichondensed benzoindolinospiropyrans and especially those of formula II is described in Techniques of Chemistry, Volume III, Chapter III, p. 254-257, from WileyInterscience, 1971. Briefly, they are prepared by a condensation reaction between two molecules of the corresponding indole compound and a molecule of the corresponding salicylic aldehyde.
In general, the color former for use in the first color forming system should be one which produces a color of a relatively pure color 20 tons, such as red, blue or green, and the precursor should be such that it decomposes into colored forms which can give a color change by forming a color , which in combination with the first one produces a more or less neutral color tone, which is obviously different from the first color.
The practical minimum amount of the components of the color-forming systems is governed by the required image darkness and the practical maximum amount is determined by economic considerations and the desired properties of the coated sheets. Such amounts include the optimum amounts used according to the present invention, which can be readily determined by one of ordinary skill in the art.
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The temperatures at which the color is obtained by the color changes are important only by being within a practical range of the intended function, i.e. within a thermographic temperature range, and when used with the thermally sensitive recording material they should be sufficiently different from one another. A suitable range for the intended function is from about 60 to about 200 ° C. An acceptable difference between the temperatures of about 20 to 30 ° C is desired, although a minor difference can be used if desired.
The present invention includes the possibility of using more than one precursor to obtain a thermally sensitive recording material, which contains more than two pre-forming systems. A further precursor shall be decomposed at a sufficiently higher melting point than the precursor already present and shall provide a color former capable of forming a further color by generating a color which, in combination with the first and second, is visibly distinct. from those obtained from the combination of deft first and second only and also from that obtained only from the first. Of course, the color forming system utilizing additional precursors together with the first and second color forming systems cannot interfere with each other.
The thermally sensitive composition may be applied to the carrier sheet as a single layer with all color forming systems therein, or as a plurality of layers with each layer containing only one color forming system. However, a carrier sheet coated with a composition in a layer has advantages over sheets coated with multiple layers by obtaining a sharper and more distinct thermal image. Furthermore, the use of a single layer requires less material and reduced manufacturing costs. It also results in a sheet with more desirable handling properties. Accordingly, a sheet carrying a single layer of terry-sensitive composition is preferred.
In addition to the components of the color-forming system, the thermally sensitive composition contains a thermographically acceptable binder in which the components are evenly distributed. The binder serves to retain the components of the carrier sheet and protects them from brushing and handling that occur during storage and use of the recording material. Preferred water-soluble binders include polyvinyl alcohol, hydroxyethyl cellulose, methyl cellulose, starch, modified starch, gelatin and the like. In some cases, latexes can be used as binders and examples thereof include polyacrylates, polyvinyl acetates, polystyrene and the like. The binder to be used in sufficient quantity to perform its function, which, however, must not interfere with reactive contact, is obtained between the appropriate color forming components. Generally, from 1, preferably 5, to about 30% by weight of the dry composition is used if the binder is used, in one or, where applicable, each layer.
The thermally sensitive composition may also, if desired, contain an additive such as a wax, clay, filler, colorant or bleaching agent in such amounts as are suitable for achieving the purpose but not causing changes in the thermal response of the resulting recording material.
The nature of the carrier sheet is not critical according to the present invention.
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They may consist of a fabric, tape, tape, film, card or the like, which may be opaque, transparent or translucent and also colored. It can be made from a film, for example, cellophane or synthetic polymeric sheets, but is preferably made of fibrous material, including especially cellulose fibers. Sheets of paper are very much preferred as carrier sheets.
In the preparation of recording material of the present invention, wherein the thermally sensitive composition consists of a single layer, a dispersion in an aqueous medium is prepared from the color forming components of each system and a thermographically acceptable binder, after which the resulting dispersion is applied to the carrier sheet and dried. In the much less preferred construction where the thermally sensitive composition consists of a plurality of layers with each layer containing a color forming system, a dispersion of the color forming components and binders is prepared in an aqueous medium for each layer and then the dispersion is applied firstly. the layer is a carrier sheet and dried and the dispersion causes the second layer to be coated on the previous layer and dried.
Normally, each color-forming component is first dispersed individually with a binder in an aqueous medium and ground to an average particle size of about 5 µm. Thereafter, all the dispersions are combined to form a single layer, while for the multi-layer composition, the dispersions of the colorants and the co-reactants are separately combined to obtain a dispersion for each layer described above.
The dispersions preferably contain surfactants and examples of such are the following anti-foaming agents - sodium lauryl sulfonate,
<img file="SE443535B_D0004.tif" />
7812551 octanol, and. acetylenic glycol, a silicone and a fatty acid ester.
The coating weight of a single-layer composition is not critical but generally contains from 2-8 grams of the ratio between the first color-forming system and the second color-forming system, preferably from 1: 1 to 1:10, and the weight ratio of the color-forming or precursors of the co-reactants. is preferably from 1: 1 to 1:12, preferably from 1: 1 to 1: 6.
However, for compositions consisting of a plurality of layers, care must be taken to utilize sufficient weights to obtain distinct colors while allowing adequate heat transport from one layer to the next. Coating weights for such layers can be practically between 1.5 to 8, preferably 2 from 3 to 6 grams per m. As a general rule, color-forming components in layers near the support surface should be present in increased amounts to overcome the masking effect of the layers above.
In order to better illustrate the invention, the following detailed description discloses a prior art system as an example thereof and three examples according to the invention where all parts relate to parts by weight.
Comparative Examples of Prior Art
In this comparative example and in all the following examples, a dispersion of each color-forming component is first prepared by grinding the component in a solution of polyvinyl alcohol (of a film-forming water-soluble quality) in water containing a surfactant until a particle size of 3 µm is reached. The painting was done in a ball mill or using a friction mill.
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The proportions of the constituent materials in the resulting dispersions
<td colspan="2">sions were as follows:</td>
<td>Incoming material</td><td>parts</td>
<td>Color forming component</td><td> 10-30</td>
<td>polyvinyl alcohol</td><td> 1-5</td>
<td>Surfactant</td><td> 0-0.1</td>
<td>Water</td><td> 65-89</td>
The dispersions thus prepared where the color-forming component was (i) 2'-methoxy-6'-diethylaminofluorane; (ii) 2'-anilino6'-diethylaminofluorane and (iiiX, 4'-β-propylidene diphenol.
Four parts of (iii) were mixed with part of (i) and the resulting merged dispersion (1) was coated onto a sheet of paper at a weight of about 5 g / m dry weight. This coating was dried and heated to 100 ° C to give a red color.
Four parts of (iii) were mixed with part of (ii) and resulted in a mixed dispersion (2) and loaded onto a paper in an amount of 5 grams / m dry weight. This coating, when dried, gave no color below about 110 degrees but turned green at about 120 ° C and above.
The two combined dispersions (1 and 2) are coated on a two-sheet paper sheet, one on top of the other. The combined dispersions (1 and 2) are then mixed and coated onto another sheet as a single layer. The sheet-bearing two-layer composition changed to blackish red at about 100 ° C and the blackish red color gradually darkened to black at a temperature when the temperature was raised to about 120 ° C.
<img file="SE443535B_D0005.tif" />
781255116 the other layer composition was blackened immediately at about 100 °. This occurred because the low-temperature melt of one color served as co-solvent for the other - and thus both color generators gave one color together.
Further, the two combined dispersions (1 and 2) above are coated onto a sheet of two-layer paper separated from one another by a clear layer of an insulating polymeric material. A red color was obtained at about 100 ° C and was pure in color tint until the temperature rose to about 110 ° C. Above 120 ° C, a combination of red and green gave a black color change. The insulating polymer layer on such a coated sheet of paper gave the desired sharp color change which is characteristic of the present invention but is difficult and expensive to manufacture.
EXAMPLE 1
The dispersions were prepared as follows:
Incoming material
A crystal violet lactone
polyvinyl alcohol
Water
B 4,4'-r-propylidene diphenol
Polyvinyl alcohol Water
C Thioadipamide Polyvinyl alcohol Water
D Nickelacetonylacetonate Polyvinyl alcohol Water
parts
22.5
2.5
2215
2.5
22.5
2.5
7812551-5 £ Nickel Naphthene Polyvinyl Alcohol Water
The dispersions were then mixed as follows:
A
B
C
D
E
Parts and the resulting combined dispersion were used to coat a sheet of paper in an amount of 4.5 to 6.0 grams / m 2 dry weight and dried.
The dye-forming component A (dye-forming agent) and B (phenol co-reactant) were used in the first dye-forming system and component C (the precursor), D and E (both metallic co-reactants) were used in the second dye-forming system.
When the composition was heated to about 120 ° C, the lower thermographic temperature, a light blue color was obtained from a reaction between the color forming components of A and B and this color was pure to about 140 ° C. At 149 ° C, the higher thermographic temperature, the color changed rapidly to black as a result of the formation of a metallic sulfide from a reaction between the color former, hydrogen sulfide formed by decomposition of C (the thioamide precursor) and D and E (the metallic co-reactants). ).
<img file="SE443535B_D0006.tif" />
781255118
Crystal violet lactone in A was replaced by 6'-diethylamino-1,2'-benzofluorane or 3,3-bis- (1-ethyl-2-methylindol-ylyl) phthalide (indolyl red) and a red color was obtained at 120 ° C.
Crystal violet lactone in A was replaced by 6'-diethylamino-2'-benzylaminofluorane and a green color was obtained at 120 ° C.
The thermally sensitive recording material in which the composition is coated on two sheets of paper, one layer containing A and B and the other, C, D and E, also produced a sharp change in color at the higher thermographic temperature.
EXAMPLE II
The dispersions were prepared as follows:
Incoming material
A. 2'-Butoxy-6'-diethylaminofluorane
Divide polyvinyl alcohol water
B 4 '- (1,3,3-trimethyl-indolenyl) 6'-chloro-8'-ethoxy-1,3,3-trimethylbenzoindolinospiropyran polyvinyl alcohol
Water
C 4 ', 4'-β-propylidene diphenol polyvinyl alcohol water
The dispersions were treated as follows:
7812551-5
Parts and the resulting combined dispersion were used to coat a sheet of paper as in previous examples.
Both the colorant A and the spiropyran resulted in decomposition of the precursor B and reacted with the phenolic co-reactant C. The sheet, when heated to 110 ° C, gave a red color which became completely clear to about 140 ° C and turned brownish black at about 150 ° C.
EXAMPLE III
The dispersions were prepared as follows:
Ingredient Parts
A 4 '- (1,3,3-trimethyl-indolenyl) -6'-chloro8' -methoxy-1,3,3-trimethylbenzoindolinospiropyran 13
2'-bromo-3'-methyl-6'-dietylaminofluoran2
3,3-bis (1-ethyl-2-methylindol) -3-yl) phthalide2 polyvinyl alcohol3 water80
B 4,4'-i-propylidene diphenol9
ACRAWAX C * 8
Bindemedel3
Water 80 x Reaction product from hydrogenated castor oil and ethanolamine, insoluble in boiling water, melting point at 140 -143 ° C, flash point at 285 ° C in open cup, density 0.97 at 25 ° C and available as a fine powder from Glycol Chemicals, Inc., New York, USA.
7812551
<img file="SE443535B_D0007.tif" />
The dispersions were mixed as follows:
parts
102 and the resulting composition was used to coat a sheet of paper as in the previous example. Both the fluorine and phthalide colorants of dispersion A and the spiropyran obtained from decomposition of the indolenyl-blocked spiropyran from dispersion A reacted with the diphenol co-reactant of dispersion B.
The sheet, when heated to 110 ° C, gave a red color, which remained fairly pure to about 140 ° C, but converted to black at about 150 ° C.
From the above it can be seen that recording materials according to the present invention substantially reduce the overlap and interference between colors produced at different thermographic temperatures compared to previously known recording materials. Furthermore, the color changes of the present recording material are much sharper because no additional colors are obtained until the decomposition temperature of the precursor is reached. At that temperature, a second color is obtained, which is combined with the first one and gives a distinct color change.
7812551-5
Contents8
8 sheets
Sheet 1 Sheet 2 Sheet 3 Sheet 4 Sheet 5 Sheet 6 Sheet 7 Sheet 8
40 members in 21 offices
Priority claims4
| Document | Office | Kind | Date |
|---|---|---|---|
| 86104677 | United States of America | A | |
| 86104677 | United States of America | A | |
| 861046 | – | – | – |
| US19770861046 | – | – | – |
Members40
| Document | Office | Kind | |
|---|---|---|---|
| IT7852291D0 | Italy | D0 | |
| BE872635A | Belgium | A | |
| LU80650A1 | Luxembourg | A1 | |
| US4151748A | United States of America | A | |
| IE782316L | Ireland | L | |
| DK561678A | Denmark | A | |
| ES476050A1 | Spain | A1 | |
| FI783739A | Finland | A | |
| FI783739A7 | Finland | A7 | |
| SE7812551L | Sweden | L | |
| NL7812167A | Netherlands (Kingdom of the) | A | |
| AU4228078A | Australia | A | |
| DE2853120A1 | Germany | A1 | |
| GB2011105A | United Kingdom | A | |
| JPS5492264A | Japan | A | |
| BR7808195A | Brazil | A | |
| FR2415009A1 | France | A1 | |
| ZA786661B | South Africa | B | |
| AU512720B2 | Australia | B2 | |
| GB2064153A | United Kingdom | A | |
| CH628574A5 | Switzerland | A5 | |
| CA1121158A | Canada | A | |
| GB2011105B | United Kingdom | B | |
| NL170827B | Netherlands (Kingdom of the) | B | |
| NL170827C | Netherlands (Kingdom of the) | C | |
| GB2064153B | United Kingdom | B | |
| JPS5822357B2 | Japan | B2 | |
| DE2853120C2 | Germany | C2 | |
| ATA884278A | Austria | A | |
| FI65190B | Finland | B | |
| AT373827B | Austria | B | |
| IE47515B1 | Ireland | B1 | |
| IE47516B1 | Ireland | B1 | |
| FI65190C | Finland | C | |
| HK73684A | Hong Kong, China | A | |
| HK74484A | Hong Kong, China | A | |
| FR2415009B1 | France | B1 | |
| IT1107596B | Italy | B | |
| IT7852291A0 | Italy | A0 | |
| SE443535BThis record | Sweden | B |
1 legal event, as the office reported them to INPADOC
Events
| Event | Code | |
|---|---|---|
| Patent in forceNAL | NAL |
Numbers
- Publication, DOCDB
- 443535
- Publication, EPODOC
- SE443535
- Application
- 7812551
- Application, DOCDB
- 7812551
- Application, EPODOC
- SE19780012551
Titles2
- Swedish
- TERMISKT KENSLIGT UPPTECKNINGSMATERIAL BESTAENDE AV ETT BERARARK UPPBERANDE TVA FERGBILDANDE SYSTEM VARAV DET ENA HAR EN FOREGANGARE
- English
- THERMALLY SENSITIVE RECORDING MATERIALS CONSISTING OF A CARRIER CREATING TWO PRELIMINARY SYSTEMS OF WHICH ONE HAS A PREVIOUS
Classification
- CPC, 2
- B41M5/34
- B41M5/345
- IPC, 2
- B41M5 323
- B41M5 34