JPH01154792A - Heat and pressure sensitive recording sheet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a recording sheet having a heat-sensitive recording paper with a pressure-sensitive recording function.

(Prior Art and Problems) Thermosensitive recording paper having a thermosensitive recording layer coated on one side of a base material has been widely used in recent years. This thermal recording method, which uses a thermal head, has many advantages such as non-impact, no noise during recording, no need for developing and fixing, and easy maintenance of equipment, so it can be used for computer output, calculators, etc. It has been used in a wide range of applications, including printers, medical measurement recorders, low- and high-speed facsimiles, automatic ticket vending machines, and thermal copying.

The common form of thermal recording paper is one in which colorless dyes, color developers, etc. are finely pulverized and supported in a binder, and a heat-sensitive layer is provided on the base material. By heating, the colorless dye and the color developer come into molten contact and a coloring reaction occurs, thereby obtaining an image record.

The colorless dyes and color developers used for these are generally electron-donating compounds and electron-accepting compounds, respectively. This is because the colorless dye, which is an electron-donating compound, has high reactivity, and when it comes into contact with a color developer, which is an electron-accepting compound, a colored image with a high temperature is instantly produced.
This is because it has excellent properties such as being able to obtain an appearance close to white and being able to capture various color hues such as red, orange, yellow, green, blue, and black.

Incidentally, the thermal recording system has been equipped with a copying function as well as high-speed recording, and the conventional method of copying the required number of sheets using an electrophotographic system of recordings recorded using the thermal recording system has become unnecessary. In this way, the copying function using thermal recording paper has become an effective means, but on the other hand, if there are typos or recording errors found in the original manuscript that need to be corrected, or if new information is added to the copied document, it is difficult to do so. If it is necessary to make a copy, depending on these circumstances, it is necessary to make corrections or additional records on each page with a writing instrument, or to make new copies after making corrections or additional records on the manuscript.

Japanese Utility Model Application Publication No. 55-160854 is a known document that has been improved in order to save the above-mentioned time and effort. In this publication, a substance that develops color by reacting with any of the color-forming reactive substances in the heat-sensitive 28 layer 1 of the lower sheet adjacent to the back side of the self-coloring heat-sensitive recording paper, which is arranged so that multiple sheets of recording can be obtained at the same time. A heat-sensitive and pressure-sensitive recording paper characterized in that it is provided with a microcapsule layer 2 containing the following is described. That is, when the color-forming reactants in the heat-sensitive recording layer are an electron-donating color former (colorless dye N'EI in this application) and an electron-accepting color developer (color developer in this application), the back side of the heat-sensitive recording paper is colored. It consists of a microcapsule layer in which only one of the agents and the color developer is microencapsulated.

In the case of such a structure, when a plurality of heat-sensitive and pressure-sensitive recording papers are stacked and pressed with a writing instrument, etc., the recorded image recorded on the heat-sensitive recording layer has the disadvantage that the speed of color development is slow and the color density is insufficient. There is.

(Means for Solving the Problems) In view of the above, the inventors of the present invention have conducted extensive research, and as a result, they have invented a heat-sensitive and pressure-sensitive recording sheet in which a heat-sensitive recording paper has a pressure-sensitive function. , a heat-sensitive and pressure-sensitive recording sheet formed by coating a heat-sensitive recording layer on the surface of a base material and a pressure-sensitive recording layer on the back surface, characterized in that the pressure-sensitive recording layer contains microcapsules containing only an organic solvent. The present invention provides a heat-sensitive and pressure-sensitive recording sheet.

The present invention will be explained in detail below.

An object of the present invention is to print a plurality of sheets of copy paper made of heat-sensitive recording paper by stacking them together and applying pressure using a writing instrument, etc. when making typographical errors, corrections to sentences, additional entries, etc. It can be done in one go. This is a heat-sensitive and pressure-sensitive recording sheet.

A specific example is proofreading a manuscript. A plurality of copies of a document sent by facsimile are made using the heat-sensitive and pressure-sensitive recording sheet of the present application. In this case, it is more preferable to use the recording sheet of the present invention for the facsimile itself. Next, the copies are stacked one on top of the other, proofread with a writing instrument, and pressure printed to make corrections, deletions, and additional records (additions).

By distributing the copy sheets proofread in this manner as necessary, they can be quickly sent to the subsequent process, for example, printing.

Next, the pressure-sensitive recording layer of the present invention will be specifically explained.

The microcapsules used in the pressure-sensitive recording layer contain only volatile and/or non-volatile organic solvents.

When recording, to explain it by copying three sheets, the pressure-sensitive recording layer side of the first sheet and the heat-sensitive recording layer side of the second sheet are opposed, and the pressure-sensitive recording layer side of the second sheet and the heat-sensitive recording layer side of the third sheet are placed opposite each other. Place the layer sides facing each other. (3
The sheets 1 to 1 are preferably ordinary thermal recording paper. ) Pressure printing is then performed using a writing instrument from the side of the first heat-sensitive recording layer. At the same time as pressure printing, the microcapsules in the first and second pressure-sensitive recording layers are destroyed, and the encapsulated zero-organic solvent flows out, dissolving the colorless dye and color developer in the heat-sensitive recording layer. Color develops when they come into contact with each other.

Both volatile and non-volatile organic solvents are effective, but volatile ones that instantly dissolve the electron-donating colorless dye and electron-accepting compound (developer), which are the coloring components in the heat-sensitive recording layer, are effective. Solvents are effective.

That is, when the colorless dye and the color developer are dissolved in the blinking spout by a volatile solvent, they come into contact with each other as a dissolved solution and a coloring reaction occurs.

When a wax is used together with the microcapsules in the pressure-sensitive recording layer, the organic solvent that flows out due to the destruction of the microcapsules is transferred to the second and third heat-sensitive recording layers without penetrating into the base material. color development can be facilitated.

In addition, if I were to add anything to the effects of waxes, the organic solvent contained within them would be absorbed by the microcapsules due to pressure and be absorbed into the base surface, reducing transferability. This is due to the fact that the wax provides a water-repellent and oil-repellent effect, and the organic solvent is transferred to the heat-sensitive recording layer, leading to improved transferability.

The coating layer components used in the present invention will be specifically illustrated below.

Examples of organic solvents encapsulated in microcapsules include volatile organic solvents and nonvolatile organic solvents.

For example, volatile organic solvents include benzene, toluene,
Aromatic hydrocarbons such as xylene, methyl alcohol,
There are volatile solvents such as alcohol-based solvents such as ethyl alcohol, isopropyl alcohol, and butyl alcohol, and ketone-based solvents such as acetone, methyl ethyl ketone, diethyl ketone, and methyl cyclohexanone.

Examples of nonvolatile organic solvents include nonvolatile solvents such as alkylnaphthalenes, chlorinated paraines, diarylethanes, alkyldiphenyls, aromatic esters, and aliphatic esters.

These exemplified organic solvents can be used alone or in combination.

In the present invention, the above-mentioned volatile organic solvents are preferred, but when considering the storage stability of the organic solvent encapsulated in the microcapsules, it is preferable to use a non-volatile organic solvent (Jf).

Further, waxes can be added to the pressure-sensitive recording layer in order to impart the effects of the waxes described above. for example,
Waxes that can be used include animal waxes such as beeswax, spermaceti wax, Chinese wax, and lanolin, vegetable waxes such as candelilla wax, carnauba wax, book wax, rice wax, and cane wax, montan wax, and osikelite. , mineral waxes such as ceresin and lignite wax, petroleum waxes such as paraffin wax and microcrystalline wax, modified waxes such as montan wax MQ derivatives, paraffin wax derivatives, and microcrystalline wax derivatives, castor wax, opal wax, etc. Hydrogenated wax, low molecular weight polyethylene and its derivatives, Acra wax,
Synthetic waxes such as distearyl ketone, caproic acid amide, caprylic acid amide, pelargonic acid amide, capric acid amide, lauric acid amide, tridecylic acid amide, myristic acid amide, stearic acid amide, behenic acid amide, ethylene bisstearic acid amide, etc. Saturated fatty acid amide wax, caproleic acid amide, myristoleic acid amide, oleic acid amide, lysic acid amide, linoleic acid amide,
Unsaturated fatty acid amide waxes such as erucamide, ricinoleamide, and linoleamide can be used alone or in combination. Microcapsules can be manufactured by methods known in the art. For example, the phase separation method from an aqueous solution as described in US Pat. No. 2,800,457 and US Pat.
574, 42-446, and 422-771. Interfacial polymerization method as shown in Tan Publications, 1986-1990.
1n-s by polymerization of seven polymers as shown in Publication No. 79 etc.
itu method, British Patent No. 952807, British Patent No. 96507
The melt decomposition cooling method shown in the specification of No. 4, etc., U.S. Patent No. 3
Examples include, but are not limited to, the spray drying method shown in British Patent No. 111407, British Patent No. 930422 @ Specifications, etc. In addition, wall film forming materials include gelatin, gum arabic, starch, sodium alginate,
Ethyl cellulose, carboxyethyl cellulose, polyvinyl alcohol, polyethylene, polyamide, polyester, polyurethane, polyethyleneimine, etc. are used.

In addition, capsule protectants such as cellulose powder, starch particles, and plastic particles, inorganic pigments such as talc, calcium carbonate, zinc oxide, and titanium oxide, organic pigments such as urea-formalin resin, dispersants, antifoaming agents, desensitizers, etc. may be added.

Examples of the coating method include coating the entire surface of the support using an air knife coater, blade coater, gravure coater, etc., or coating a part of the base material using a flexible printing machine, gravure printing machine, etc. It will be done.

The coating order is to coat the heat-sensitive recording layer on the surface of the base material,
It is preferable to smooth the surface using a super calender, a machine calender, etc., and then apply a pressure-sensitive recording layer to the back surface thereof, but the reverse method may be used.

The base material can be arbitrarily selected from transparent, translucent, and opaque materials. For example, paper, various nonwoven fabrics, synthetic paper, metal foil, plastic film, etc., or a composite sheet made of a combination of these may also be used.

Next, the heat-sensitive recording layer will be described in detail, and the coating layer components may be those commonly used.

As the electron-donating colorless dye, commonly used electron-donating colorless dyes can be used, such as crystal violet lactone, 3-diethylamino-7-methylfluoran, 3-dieble 7 minnow-chloro-7-methylfluoran, 3-diethylamino-6-methyl-7-chlorofluoran, 3-diethylamino-7-anilinofluoran, 3-diethylamine-7-(2-chloroanilino)fluoran, 3-diethylamine-7-(3-chloroanilino)fluoran , 3-diethylamino-6-medy-7-anilinofluorane, 3-(N-ethyl-p-
t-luidino)-6-methyl-7-anilinofluorane, 3-(N-methylhexylamino)-3-methyl-7
-anilinofluorane, etc.

As the electron-accepting compound (color developer), acidic substances generally used in thermal paper can be used, such as phenol,
p-tert-butylphenol, p-phenylphenol, α-naphthol, p-hydroxyacetophenol, 2,2'-hydroxydiphenol, 4,4'-
Isopropylidene bis(2-tert-butylphenol), 4.4'-isopropylidene diphenol, 4,
4'-cyclohexylidene diphenol, novolac type phenol resin, benzoic acid, p-tert-butylbenzoic acid, p-oxybenzoic acid, p-oxybenzoic acid benzyl ester, p-oxybenzoic acid methyl ester, 3
-benzyl-4-hydroxybenzoic acid, β-naphthoic acid, salicylic acid, 3-tert-butylsalicylic acid, 3
-Methyl-5-tert-butylsalicylic acid, stearic acid, oxalic acid, maleic acid and the like.

Low melting point substances include waxes such as paraffin wax, microcrystalline, wax, polyethylene wax, beeswax, rice wax, candelilla wax, carnauba wax, montan wax, osikelite, ceresin, castor wax, opal wax, and stearamide. , behenic acid amide, ethylene bisstearic acid amide, methylol stearic acid amide, and oleic acid amide.

The following additives may be added as desired.

As a binder, for example, starch, hydroxyethyl cellulose, methyl cellulose, polyvinyl alcohol 1.
Examples include styrene anhydride-maleic acid copolymer, styrene butadiene copolymer, and polyacrylamide.

Pigments such as diatomaceous earth, talc, kaolin,
Examples include calcined kaolin, r:AM calcium, magnesium carbonate, titanium oxide, silicon oxide, aluminum hydroxide, urea-formalin resin, and the like.

(Example) The present invention will be specifically described below with reference to Examples.

In addition, "parts" in the examples indicate parts by weight of solid content.

Practical IM Example 1 10 parts of 3-diethylamino-6-methyl-anilinofluorane and 30 parts of a 2% aqueous polyvinyl alcohol solution were dispersed in a ball mill for 2404 minutes. On the other hand, 2,2-
25 parts of bis(hydroxyphenyl)propane was mixed with 75 parts of a 2% polyvinyl alcohol aqueous solution in a ball mill for 24 hours.
Time-dispersed, roughly 2,3-dimethoxynaphthalene 10
part was dispersed in a ball mill for 24 hours with 30 parts of a 2% polyvinyl alcohol aqueous solution. After mixing these three dispersions, add 80 parts of a 50% dispersion of 1 cum calcium carbonate, add 25 parts of a 20% dispersion of zinc stearate,
180 parts of a 10% polyvinyl alcohol aqueous solution and 75 parts of water were added and thoroughly stirred to prepare a coating liquid.

The coating liquid was coated on a base paper having a tsubo m of 559/rr to a solid coating weight of 69/rd, dried, and treated with a supercalender to obtain a heat-sensitive recording paper.

A pressure-sensitive recording layer is provided on the back side of the heat-sensitive recording paper obtained above.
The coating liquid used for the pressure-sensitive recording layer is as follows.

(1) A microcapsule dispersion containing a volatile organic solvent was prepared as follows.

100 parts of toluene was prepared as a volatile organic solvent.

The above toluene was emulsified in 200 parts of a 5% ethylene-anofomaleic acid aqueous solution, and the pH of the system was adjusted to 4.0. urea 10
After adding 200 parts of an aqueous solution containing 1 part and 2 parts of resorcin to the emulsion, and further adding 25 parts of a 37% formalin aqueous solution, the temperature of the system was maintained at 55 °C and the reaction was carried out for 3 hours, followed by cooling and p[= 1 was set to 8°0, and encapsulation was completed.

(2) The following aqueous coating liquid was prepared using the toluene-encapsulated microcapsules prepared in (1) above.

Toluene-containing microcapsules 40 parts Paraffin wax emulsion 15 parts Wheat starch
30 parts SBR latex
15 parts of each of these materials were blended and water was added to prepare a water-dispersible coating liquid with a solid content of 2 to 1 part per volume.

The thus prepared water-dispersible coating liquid was applied to the back side of a heat-sensitive recording paper, which had previously been coated with a heat-sensitive recording layer, at a coating weight of 6 g/TIt, and the pressure-sensitive recording layer was removed.

Printability was examined using the recording sheet obtained in Example 1 as follows.

Three copies of the previously prepared character manuscript were made on the recording sheet prepared in Example 1 (using a heat-sensitive recording layer) using a high-speed facsimile (Matsushita Electric Transmission V tJF-920). The copied recording sheets were stacked one on top of the other with the printed surface (thermal recording layer) facing up.

Next, pressure was applied to the printed surface using a ballpoint pen to correct characters and make additional entries. After correcting in this way, 3
When the sheets were separated, the pressed characters from the ballpoint pen on the first sheet could be obtained as clear black recorded characters on the heat-sensitive recording layers of the second and third sheets.

(Effects of the Invention) As described above, the heat-sensitive and pressure-sensitive recording sheet of the present invention has two layers, a heat-sensitive recording layer and a pressure-sensitive recording layer, and a plurality of recording sheets that have been copied into a heat-sensitive recording layer can be printed at one time. Characters can be corrected and added by applying pressure, and its uses can be wide-ranging.

Claims (1)

[Claims] 1) A heat-sensitive and pressure-sensitive recording sheet formed by coating a heat-sensitive recording layer on the surface of a base material and a pressure-sensitive recording layer on the back surface, characterized in that the pressure-sensitive recording layer consists of microcapsules containing only an organic solvent. Heat-sensitive and pressure-sensitive recording sheet.