JPS58205145A - Thermodevelopable diazo type recording material - Google Patents

Abstract

PURPOSE:To obtain a diazo type recording material good in color development thermosensitivity, and enhanced in humidity resistance, chemical resistance, etc., by forming a recording layer contg. a binder resin having a glass transition point in a specified range, and a specified polybasic acid and a specified alkyl- substd. guanidine salt. CONSTITUTION:The thermodevelopable diazo type recording material enhanced in humidity and chemical resistance without impairing color development thermosensitivity is obtained by forming on a support a recording material contg. as a thermodeveloping agent, a salt of a guanidine represented by the formula (one of R1, R2 or both are 8-24C alkyl, and the other is same or H or 1-7C alkyl) and a polybasic acid having 2X10<-1>-1X10<-4> primary dissociation constnat; a polymer binder having a glass transition point in 60-130 deg.C; diazonium borofluoride; an aromatic hydroxy compd. having a sulfamoyl or carbamoyl group in the molecule; and an acid stabilizer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-developable diazo type recording material that can be fixed (processing to prevent uncolored areas from recoloring due to heat).

Conventionally, there are many known image recording methods for converting information into visible images. In general, physical energy is generated in response to energy such as radiation, electrolysis, magnetism, heat, pressure, etc.
Alternatively, chemical changes occur to form images.

For example, there are two types of recording methods that use heat: one that forms images using physical changes such as melting, sublimation, and volatilization, and one that forms images that utilizes color development due to chemical changes caused by heat. . However, since such a heat-sensitive recording medium has a structure VCfc in which a recorded image is obtained by heat, the non-image area also has the ability to develop color when heat is applied later. Therefore, if you accidentally bring it close to heat, it will develop color and lose its ability as a recording medium. + is negative. Therefore, this additional improvement is desired in the general market.

Therefore, in recent years, a heat-developable diazo type recording material, which is a dry imaging system, has been attracting attention as a heat-sensitive recording material and is being developed for practical use.

Here, heat-developable diazo type recording bodies can be roughly classified into three types. That is, they are an alkali precursor type, a coupler precursor type, and a diazo precursor type. These three types of image forming methods are the same in terms of phenomenon; first, a diazo compound and a coupler undergo a campling reaction using thermal energy to form an image with an azo dye, and then the entire surface is irradiated with light energy. The color development ability of the unimaged area is lost and fixed to form a permanent image. The difference between the three types of image forming methods is the method of inducing the coupling reaction. Specifically, in the case of the alkali precursor type, thermal energy causes chemical changes such as decomposition, dissociation, and melting of the thermal developer, and the recording layer is placed in an alkaline atmosphere), and a coupling reaction occurs between the diazo compound and the coupler. This is a method of forming an image using an azo dye.The coupler precursor type uses a coupler that is inactive in the coupling reaction at normal temperatures, and is activated by thermal energy to cause a camping reaction with the diazo compound to form an image of the azo dye. The diazo precursor type is a method of structural isomerization reaction of diazosulfonate by light using flI, in which the anti-type diazosulfonate, which is inactive in the cambling reaction, isomerized to the active syn-type by light energy. This method uses thermal energy to cause a coupler reaction with the coupler to form an image using an azo dye.

Heat-developable diazo recording materials using the three types have already been published publicly, and numerous patents have been issued.

For example, US Pat. No. 265 as an alkali precursor type.
Heat-developable diazo type recording materials and recording materials using various color development aids are described in Japanese Patent Publication No. 5091, Japanese Patent Publication No. 8500/1980, Japanese Patent Publication No. 10248/1982, Japanese Patent Publication No. 3926/1982, etc. .

Power, as a puller precursor type, Special Publication Showa 45-4015
Publication No. 3, Special Publication No. 47-11797, Special Publication No. 11797
JP-A No. 1562 and Japanese Patent Publication No. 14522/1987 describe heat-developable diazo type recording materials using 2,3-dihydrox7benzoic acid derivatives as couplers which are activated for coupling by thermal energy. and US Pat. No. 2,217,189 as a diazo precursor type,
British Patent No. 544702, German Patent No. 73430
No. 2 and Japanese Unexamined Patent Publication No. 56-5790 describe a recording medium comprising a diazosulfonate compound, a coupling agent, and a polymer binder, and a recording method thereof.

However, these conventional heat-developable diazo recording materials,
Like the alkali precursor type, it has heat-sensitive coloring sensitivity but lacks storage stability.On the other hand, like the coupler precursor and diazonium precursor types, it has storage stability but has coloring sensitivity that is compatible with the mechanism. It had the disadvantage of not having For this reason, various improvements are being made and development is underway to put it into practical use, but a practical heat-developable diazo recording material that has both heat-sensitive coloring sensitivity and storage stability has not yet been completed. is the current situation.

As a result of conducting additional experiments on the conventional heat-developable diazo type recording material, the present inventors found that the difference in heat-sensitive coloring sensitivity is due to the recording material. The heat-sensitive coloring sensitivity of each body type is due to the heat-sensitivity of the coupler and diazosulfonate, respectively. The thermal sensitivity of these organic compounds is determined by the position or type of substituents. However, although some improvement can be seen even if a substituent that improves the thermal sensitivity is added, the recording material has the disadvantage of not being able to achieve the thermal sensitivity intended by the inventors due to its structure. The above two types were unsuitable for practical use.

Therefore, the present inventors investigated the characteristics of the alkali precursor type,
That is, focusing on the high heat-sensitive coloring sensitivity, we synthesized a number of substances for the heat developer that determines the heat-sensitive coloring sensitivity of the type, and developed heat-sensitive diazo type recording materials using each synthetic material as the heat developer. As a result of investigating color development sensitivity and storage stability, it was found that a heat-developable diazo type recording medium using a salt of a certain type of guar-zine compound as a heat developer has excellent storage stability and good heat-sensitive color development sensitivity. The inventors discovered that the invention had the same property, and filed an application as Japanese Patent Application No. 57-011245.

As a result of intensive research to further improve the practicality of recording media than the above patent application, the inventors of the present invention have created a recording composition in order to improve humidity resistance and chemical resistance without impairing heat-sensitive coloring sensitivity. The present invention was achieved by limiting the coupling agent to a hydrophobic one and further using a thermoplastic resin with a glass transition point in the range of 60 to 150°C as the polymer binder. .

That is, the present invention provides diazonium borofluoride,
As a coupling agent, sulfamoyl (su
lfamoyl group or carbamoyl group
yl) group, an acid stabilizer, a salt of alkyl-substituted guanidine as a heat developer, and a thermoplastic resin selected from the glass transition temperature range of 60 to 160°C as a polymer binder. The present invention is a heat-developable diazo type recording material characterized by being provided with a recording layer made of recording components.

The heat-developable diazo type recording material of the present invention is an alkali precursor type, and as a heat developer, the -order dissociation constant is 2XI.
D"-' to IX1 [1-' polybasic acid (represents an inorganic or organic acid higher than -basic acid) and the general formula % formula % (However, at least one of R1 and R, 2 is C8~
The C24 alkyl group is a hydrogen atom or a C1 or more alkyl group. ) is characterized by using a salt with an alkyl-substituted guanidine.

In the present invention, the above-mentioned properties of the alkyl-substituted guanidine salt have superior properties compared to conventionally known thermal developers, namely: 1) The alkyl-substituted guanidine has more hydrophobic properties than hydrophilic properties.

2) Salts of alkyl-substituted guanidines are poorly soluble in water and are neutral or weakly acidic.

3) The salt of alkyl-substituted guanidine is stable at room temperature, and can instantly form a coupling-active atmosphere at around 100°C.

In order to fully demonstrate this, in order to suppress the pre-coupling phenomenon between the diazonium compound and the coupling agent due to humidity, a sulfamoyl group or a sulfamoyl group or It is characterized by using an aromatic hydroxy compound having a carbamoyl group.

Furthermore, the heat-developable diazo type recording material of the present invention uses a polymer binder with a glass transition point of 60 to improve the adhesion between the recording material and the support, coating uniformity, water resistance, and chemical resistance. It contains a thermoplastic resin with a temperature of ~130°C, and the reason why the range of the glass transition point is limited is to prevent a decrease in heat-sensitive coloring sensitivity.

Also, what I would like to pay attention to here is that when a thermoplastic resin with a glass transition point of around 100°C is used as a polymer binder for the recording layer, there is a risk of residue adhesion to the thermal head and sniping during thermal printing of a thermal printer. King phenomenon is likely to occur, but
The thermal developer used in the present invention plays a role in preventing this phenomenon. That is, the alkyl-substituted guanidine salt used in the present invention as a thermal developer has a linear alkyl group in its molecule, and thus plays the role of a lubricant.

Such a heat-developable diazo type recording material has much better storage stability than conventionally known recording materials, and at the same time, it has a heat-sensitive coloring sensitivity comparable to that of a heat-sensitive secondary coloring recording material made of a leuco dye system. , and can form an azo dye image with a reflection density of 10 or more, and has excellent chemical resistance after fixing, and provides a heat-developable diazo-type recording sickle body with unprecedented properties. It is.

Here, the hydrophobic coupling agent used in the present invention, that is, a couplingable aromatic hydroxy compound having a sulfumoyl group or a carbamoyl group in the molecule, includes 2,5-dihydroxynaphthalene-6-sulfonamide, 2-naphthol-6,6-disulfonamide, 2.8-dihydroxynaphthalene-6-sulfonamide, 1.8-dihydroxynaphthalene-8-sulfonamide, 1-8-aminonaphthol-5-sulfonamide, 2.7 -cyhydroxy-3,6-disulfonamide, 1,8-henshylaminonaphthol-2-sulfonamide, 1,8-dihydroxynaphthalene-6-sulfonamide, 2-acetoacetaminonaphthalene-6-
Sulfonamide, 2-acetoacetaminonaphthalene-
7-sulfonamide, 2-acetoacetaminonaphthalene-8-sulfamide, 1-acetoacetaminonaphthalene-4-sulfamide, 1-acetoacetaminonaphthalene-5-sulfonamide and derivatives of these sulfonamides, 2-hydroxy -6-naphthoic acid propylamide, 6-promo-2-hydroxy-3-naphthoic acid propylamide, 2-hydroquine-3-naphthoic acid phenylamide, 2-hydroxy-3-naphthoic acid 0-tolylamide, 2-hydroxy-6 -naphthoic acid m-)lylamide, 2-hydroxy-5-naphthoic acid p-)lylamide, 6-promo-2-hydroxy-3-naphthoic acid o
-M+ ruamide, 6-bromo-2-hydroxy-3-su7) engineering acid m-)') ruamide, 6-bromo-2-hydroxy-3-naphthoic acid p-tolylamide, 1-hydroxy-2-naphthoic acid propyl Amide, 1-hydroxy-
2-naphthoic acid 0-tolylamide, 1-hydroxy-2
-naphthoic acid m-)lylamide, 1-hydroxy-2-
Examples include naphthoic acid p-)lylamide.

The recording materials other than the coupling agent used in the present invention will be described in detail below.

Various known diazo compounds can be used as the diazo compound used in the present invention. For example, paraphenylenediamine N-N-substituted compounds (4-diazo-N-diethylaniline etc.), aminohydroquinone ethers (4-
Diazo-2-5-diptoxy-N-N-diethylaniline, 4-diazo-2-chloro-5methoxy-N-benzoylaniline etc), aminodiphenyl, aminodiphenylamine and similar compounds (4-diazo-2s
al) rioxydiphenylamine etc.), heterocyclic amine derivatives (4-diazo-2-5-dibutoxy-N-phenylmorpholine etc.), etc.The diazo compounds mentioned above include diazonium borofluoride, etc. Used as an organic solvent-soluble salt of

Next, as a hydrophobic thermal developer, the -order dissociation constant is 2X1
A polybasic acid of 0-' to l
A salt with an alkyl-substituted guanidine represented by the following formula can be used.

Such a salt of alkyl-substituted guanidine has extremely low solubility in water, which is on the order of several ml or less in 100fi4 of an aqueous solution. That is, the guanidine compound has more hydrophobic properties than hydrophilic properties. As an acid that can form an appropriate salt with an alkyl-substituted guanidine exhibiting hydrophobicity, the first-order dissociation constant is 2xi.
Polybasic acids ranging from o' to lX10-' can be selected.

More specifically, examples of the alkyl-substituted guanidine include octylguanidine, nonylguanidine, decylguanidine, undecylguanidine, laurylguanidine,
Tridecylguanidine, myristylguanidine, hexadecylguanidine, octadecylguanidine, icosylguanidine, tocosylguanidine, dioctylguanidine, dioctadecylguanidine, N-methyl-N-octadecylguanidine, N-methyl-N-decylguanidine, N,N -didecylguanidine, etc.

- On the other hand, examples of polybasic acids having a first-order dissociation constant of 2 x 10-1 to 1 x 10-' that can form salts with alkyl-substituted guanidines include benzenesulfonic acid, trichloroacetic acid, oxalic acid, glycerophosphoric acid, maleic acid, phosphoric acid,
Citric acid, malonic acid, tartaric acid, malic acid, lactic acid, etc. are suitable.

Furthermore, the alkyl-substituted guanidine salt used in the present invention can be synthesized by a known method.

That is, a solution of alkyl-substituted guanidine dissolved in a suitable solvent is heated to 50° C., and while stirring, a stoichiometric amount of the dissolved solution is added dropwise. By continuing stirring for about 10 minutes after the completion of the dropwise addition, the product can be produced with a yield of about 100%.

Next, as the acid stabilizer used in the present invention, various known nonvolatile acids used for diazo type materials can be used. For example, citric acid, gluconic acid, oxalic acid, tartaric acid,
These include sulfamino acid, hydroxylamine hydrochloride, boric acid, and phosphoric acid. In addition, even if thiourea, L-ascorbic acid, urea, allyl inthiocyanate, etc. are used as antioxidants to improve the storage stability of the recording medium after recording, the coloring sensitivity and storage stability of the recording medium of the present invention can be improved. It won't harm your sexuality.

Furthermore, the thermoplastic resin selected from glass transition points of 60 to 130°C as a polymeric binder used in the present invention includes, for example, polystyrene, polymethylstyrene,
Polyphenylstyrene, polychlorostyrene, polyxylene, polyvinyl butyral, cellulose acetate butyrate copolymer, polyethylene terephthalate, triacetyl cellulose, polyacrylate, polyacrylonitrile, polymethyl methacrylate, polymethyl/butyl acrylate, inbutyl methacrylate,
These include butyl methacrylate, polychloromethyl acrylate, polyvinyl tert-butyl ether, polyvinyl chloride salt and vinegar picopolymer, and the like.

Next, a recording layer is coated on the support in the present invention. A known method can be used to do this.

Specifically, a dispersion containing a liquid in which a recording agent consisting of a diazo compound, a coupling agent, an acid stabilizer, an antioxidant, and a polymeric binder is dissolved in an organic solvent, and a heat developer prepared in advance. A heat-developable diazo type recording material can be produced by applying a coating solution obtained by uniformly mixing the solutions onto a support such as paper, glass or film using a wire bar, and drying at a low temperature. In addition, when the recording layer has a two-layer structure, a coating liquid in which a thermal developer and a polymeric binder are uniformly dispersed in an organic solvent is applied onto the support using a wire bar, etc., and after drying. , a diazo compound, a coupling agent, on the layer,
A heat-developable diazo type recording material is manufactured by applying a solution of a recording agent consisting of an acid stabilizer, a polymeric binder, and optionally an antioxidant dissolved in an organic solvent using a wire bar and drying it. be able to.

The method for recording the heat-developable diazo recording material thus obtained is as follows:
An image is formed on the recording layer of the recording body using thermal energy, and then a permanent image is formed using heat and light energy that is fixed by irradiating the entire surface with light energy, or is transmitted through the recording layer of the recording body. A method of forming a permanent image using light and thermal energy is possible, in which the original is placed in close contact with the original, a latent image is formed by irradiating the original energy, and then thermal energy is applied to the entire surface to develop the image. However, as the energy source used here, a thermal head, a thermal pen, an infrared ray, a laser source, a thermal roll, etc. can be used as a thermal energy source. Further, as a light source for generating light energy, a mercury lamp, a xenon lamp, a tungsten lamp, a xenon lamp, and a vf-9° can be used.

Since the present invention has the above configuration, it has various effects as shown below. That is, 1) The salt of alkyl-substituted guanidine, which is a thermal developer, is hydrophobic, stable at room temperature, and easily forms a coupling-active atmosphere at around 100°C.

2) Since the diazonium compound, coupling agent, and thermal developer exhibit hydrophobic properties, the precoupling phenomenon caused by humidity during storage is suppressed.

3) Water resistance after fixing due to the use of polymer binder.
Excellent chemical resistance.

4) In addition to its role as a heat developer, the salt of alkyl-substituted guanidine, which is a heat developer, has a linear alkyl group in its molecule, so it has properties as a lubricant. Therefore, it is also useful for preventing residue adhesion and staking during thermal printing with a thermal printer.

As described above, the heat-developable diazo type recording material according to the present invention has satisfactory storage stability, heat-sensitive color development sensitivity, and chemical resistance, which have been difficult to put into practical use, and therefore can be used in various applications. For example, it is a particularly effective recording medium for computer output printers and data communication terminals, and for tickets, cards, and sticker-less commuter passes that require counterfeit prevention.

Examples of the present invention will be shown below. In each example, "part" means part by weight.

[Example 1] 3 parts of n-decylguanidine tartrate represented by the above structural formula, polystyrene (glass transition point io.

℃), 70 parts of methyl ethyl ketone, and 30 parts of toluene were uniformly dispersed using a disperser. 06 parts of oxalic acid, 2 parts of 2-hydroxy-3-naphthoic acid propylamide, and 1 part of PN,N-diethylaminobenzenediazonium borofluoride were added and dissolved in the dispersion to prepare a photosensitive solution. The photosensitive solution was applied onto 55 kg of high-quality paper using an air knife coater to produce a heat-developable diazo type recording paper. After placing a transparent original in close contact with the recording paper and exposing it to light using a Ricoh diazo copier to form a latent image,
When the entire surface was heated and developed using a hot roll at 130° C., a blue copy with an optical density of 1.5 against a pale background was obtained. Further, even when heat was applied to the uncolored portion, no blue image was formed, and a fixed bundle was obtained. In addition, after leaving the recording paper at 40°C and 20% relative humidity for 10 days or at 40°C and 90% relative humidity for 2 days, a latent image was formed with light energy and developed with thermal energy in the same manner as above. However, a blue image with an optical density of 15 was obtained, and no Pace capri was observed.

Further, even if the image area was rubbed with water-soaked gauze after fixing, the image did not change color or fade. In this way, it was possible to provide a recording paper with excellent thermal color development sensitivity and storage stability.

[Example 2] Myristylguanidine oxalate 5 shown by the above structural formula
PolyP-chlorostyrene (glass transition point 130°C)
A coating liquid consisting of 5 parts of polyester film, 70 parts of methyl ethyl ketone, and 50 parts of toluene was uniformly dispersed using a disperser and then applied onto a polyester film using a roll coater and dried. On the layer, citric acid 04 parts, thiourea 0.2 parts, P
-) A photosensitive solution consisting of 0.2 parts of luenesulfonic acid, 2 parts of 2.5-dihydroxynaphthalene-6-sulfamide, 1 part of p-morpholinobenzenediazonium borofluoride, and 3 parts of poly p-chlorostyrene was applied to a roll coater. −(
It was coated and dried at 60°C to produce a heat-developable diazo type recording film.

This recording film was printed on a Toshiba ■ thermal printer (printing conditions o45W, pulse width 2.75m5).
Further, when the entire surface was irradiated with a mercury lamp, a bluish-purple image with an optical density of 1 or 2 was obtained with a pale color background. In addition, after printing with a thermal printer, the entire surface was not exposed to a mercury lamp, and the capri quality of the 20 colors and non-image areas at 50° C. relative humidity was checked. Under the above conditions, no discoloration of the image or capri of the base was observed. Further, even if the image area was rubbed with gauze soaked in water or methyl alcohol after fixing, no discoloration or fading of the image was observed. As described above, it was possible to provide a recording film with properties that can withstand practical use.

[Example 5] On a polyester film (thickness 200 μm), a coating solution obtained by kneading a dispersion consisting of 2 parts of powdered silica, 4 parts of polyurethane resin, 8 parts of methyl ethyl ketone, and 2 parts of toluene in a ball mill overnight was applied to a roll coater. It was applied and dried to form a porous silica layer. On the layer, 6 parts of trichloroacetate of octadecylguanidine shown by the above structural formula, polymethyl methacrylate (glass transition point 6
0°C) 8 parts, methyl ethyl ketone 70 parts, toluene 30 parts
08 parts of oxalic acid, 2 parts of 2-hydroxy-3-naphthoic acid phenylamide, and 4-morpholino-2,5-dibutoxybenzenediazonium borofluoride were uniformly dispersed in a dispersion liquid using a disperser. A photosensitive liquid containing 1 part of the photosensitive liquid was applied using a roll coater and dried using a hot air dryer at 60° C. to produce a heat-developable diazo type recording material.

This recording medium was first printed using a Toshiba ■ thermal printer (printing conditions: 045 W, pulse width: 2 m5), and then the entire surface was exposed using a xenon flash (exposure energy: 450 J), resulting in an n-color image with an optical density of 1.2 against a pale color background. was formed. In addition, after printing with a thermal printer, we exposed the entire surface with a xenon flash at / - to check for discoloration, fading, and capri of the image. Under the above conditions, no discoloration, fading, or capri of the base was observed. Ta. Further, even when the direct image area was rubbed with gauze soaked in water, an aqueous solution of a neutral detergent, petroleum ether, or alcohol after fixing, no discoloration or fading of the image was observed.

As described above, it was possible to provide an excellent recording medium with properties that can withstand practical use.

Patent Applicant Toppan Printing Co., Ltd. Representative Kazuo Suzuki Procedural Amendment (Juri July 6, 1981 To the Commissioner of the Japan Patent Office 1, Indication of the case 1988 Patent Application No. 88543 2, Name of the invention Heat-developable diazo mold Record 3, Relationship with the case of the person making the amendment Patent applicant address 1-5-1 Taito, Taito-ku, Tokyo a) Detailed description of the invention in the specification column 5o Contents of the amendment a) Invention of the Meiji 41 Zhuan The detailed explanation column for τ is shown below.

, 1) In the 15th line of the 16th Tei, ``ride salt and vinegar'' is corrected to ``Urji, salted salmon and:''.

W) 20th Q 9th fT r 55 K Q's" is deleted.

2-

Claims (1)

[Claims] (1) On the support, diazonium borofluoride, an aromatic hydroxy compound having a sulfamoyl or carbamoyl group in the molecule as a coupling agent, an acid stabilizer, and a glass in the range of 60 to 130°C as a polymer binder. As a thermoplastic resin with a transition point and a thermal developer, the −order dissociation constant is 2.
A heat-developable diazo type recording characterized by providing a recording layer containing a salt of a polybasic acid of X10-' to 1X10' and an alkyl-substituted guanidine represented by the general formula 01 or higher. body.