JPS6223918B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an information recording card that can form a durable permanent image record by providing an ink absorbing layer and a slippery layer on a card base and then transferring ink using an impact printer, inkjet printer, etc. and its manufacturing method.

In recent years, there has been an increase in the number of industrial fields in which the following requirements regarding recording, printing, marking, etc. are strongly desired. In other words, information recording cards such as various securities, card certificates, commuter passes for automatic ticket gates, labels, etc. that must withstand harsh conditions of use for a long period of time have abrasion resistance, weather resistance, water resistance, and solvent resistance. The information recording method must be easy to output information stored in a computer, etc., and the mechanism and operation must be simple. . Conventionally used electrophotographic methods and electrostatic recording methods generally require complicated and large equipment, are expensive, and require consumables such as developers, which requires maintenance. This had the disadvantage of being complicated to manage. Considering this point, the impact printing method or inkjet printing method is evaluated as a preferable recording method due to its simple mechanism, low consumable materials, and low running costs, and it is recommended that paper be used as the recording medium. It has begun to be actively applied not only to facsimiles but also to information recording, which requires durability of recorded images, such as information recording cards, which are the object of the present invention.

However, in the past examples of application, in order to obtain a durable recorded image, a fixing means was further applied after the image was formed to strengthen the ink in the image area so that it would not easily peel off. This is due to the fact that the ink does not penetrate into the card substrate but merely adheres to the surface. Therefore, as fixing means for this purpose, infrared heaters, flash lamps, and ultraviolet lamps have been used for irradiation, but these devices have become complicated and have disadvantages such as increased running costs. In view of this point, as a result of intensive research, the present invention has been completed to provide a highly practical method for producing information recording cards that allow sufficient penetration of ink, are durable, and are smudge-free. It is something to do.

The recording medium of the present invention has a base 2 made of plastic, metal, or strong paper, and has an ink absorbing layer 3 on its surface that can retain ink, and further has an ink absorbing layer 3 on the surface that allows ink to pass through and prevents scumming. A two-layer recording layer including a slippery layer 4 is provided. Since the most practical method for forming this recording layer is to apply a coating liquid, the coating film will be described in detail below.

First, the method for forming the coating film of the ink absorbing layer will be described below. The basic composition of the coating liquid consists of particles, a resin that uniformly disperses and binds the particles, and an organic solvent that dissolves the resin. As specific examples of particles, all commonly used inorganic or organic white pigments can be used.

Note that if a colored recording layer is required, colored pigments may be used. For example, titanium oxide, calcium carbonate, zinc oxide, silicon oxide, barium sulfate, lead carbonate, alumina, clay, etc. can be used.

On the other hand, regarding resins, binder resins commonly used in paints and inks, such as polyester, phenyl, alkyd, acrylic,
Epoxy resins, polyurethane resins, modified cellulose resins, and mixtures thereof can be used. Kneading and dispersion for preparing a coating liquid is performed by a well-known method. This coating solution is applied to a durable substrate such as plastic or metal and dried to form an ink absorbing layer. Note that a well-known coating method may be applied for coating.

As a result of intensive studies, the following requirements were clarified in order for this coating film to have properties as an ink absorbing layer. First, the pigment/resin composition ratio is determined by the recording properties (related to the porosity of the coating film), coating film strength, adhesion to the substrate,
It shows remarkable results in terms of abrasion resistance, but in order to satisfy all the conditions, the composition ratio of pigment/resin must be in the range of 1/3 to 4/1 by weight. Although the above-mentioned full range may not be applicable depending on the pigment material type, pigment particle size, and shape, the range common to all material configurations is 1/3 to 4/1. Next, regarding the particle size and particle size distribution of the pigment, taking into account porosity and surface roughness, it is preferable that the particle size is in the range of 0.5 to 5 μm and the particle size distribution is as narrow as possible to provide good properties as an ink absorbing layer. Further, the appropriate thickness of the coating film is about 10 to 30 μm.

In order to improve the strength and solvent resistance of the coating film, it is more preferable to use a crosslinked binder resin. For example, well-known techniques can be applied as appropriate, such as selecting a polyester resin having a polyol group or a resin containing a polyurethane resin as the resin, and forming a binder resin composition by adding an isocyanate group-containing compound or resin as a crosslinking agent.

Incidentally, when the adhesive force between the substrate and the recording layer to be provided is weak, it is natural to provide an undercoat layer in advance to improve the adhesive force before coating the recording layer.

Next, the method for forming the coating film of the slipping layer will be described below. The basic composition of the coating liquid consists of white or nearly white solid lubricant particles, a binder resin that uniformly disperses and binds the particles, and an organic solvent that dissolves the resin. Specific examples of solid lubricant particles include boron nitride, sulfur, mica, talc, aluminum stearate, calcium stearate, titanium sulfide,
White or nearly white fine powders of molybdenum sulfide, polyethylene, polyacetal, polytetrafluoroethylene, etc. are suitable. As for the resin, binder resins generally used in paints and inks, such as polyester, phenyl, alkyd, acrylic, epoxy, polyurethane, modified cellulose resins, and mixtures thereof, can be used. Kneading and dispersion for preparing a coating liquid is performed by a well-known method. This coating liquid is applied onto the above-mentioned ink absorption layer and dried to form a slippery layer. Note that for coating, a well-known coating method may be applied. This slippery layer allows information recording ink to pass through,
As a result of studies to obtain properties that have lubricity that should also prevent scumming, the following requirements were further clarified. First, the solid lubricant particle/resin composition ratio has a large effect on ink permeability, coating film strength, adhesion with the ink absorbing layer, and abrasion resistance, but in order to satisfy all conditions, solid lubricant The agent/resin composition ratio should be in the range of 2/1 to 20/1 by weight. Next, regarding the particle size, if it is too small, the ink permeability will decrease, and if it is too large, the surface roughness will become too large and the scumming prevention effect will decrease, so the optimum particle size range is 0.5 to 10μ. There must be. Next, regarding the thickness of the coating film, if it is too thin, it will not be able to sufficiently cover the surface of the ink absorbing layer below, and if it is too thick, the ink permeability will decrease, so the optimal film thickness range is It must be between 2 and 10μ.

Next is the recording method, which includes the impact printing method, which presses type or wire dots, etc.
There is an inkjet printing method. These methods will be explained with reference to the drawings, but any recording device that is currently in use or developed may be used, and a detailed explanation will be omitted since it is not the gist of the present invention.

First, the ink ribbon used in the impact printing method is a commercially available ink ribbon normally used in typewriters, computer terminal printers, etc., and ribbon bases made of nylon cloth or plastic film can be used.

FIG. 2 is a conceptual diagram of an information recording card recorded by the wire dot impact printing method as an example of the impact printing method. The information recording card 1 includes a base 2, an ink absorption layer 3, and a slippery layer 4 provided thereon. When the ink from the ink ribbon 5 is transferred onto the card 1 by a wire dot impact printer, the ink is transferred to the slippery layer 4.
The ink is absorbed and held in the ink absorbing layer 3. The third example shows an inkjet printing method in which information recording is visualized by a part of the ink 6 that has passed through and permeated into the overcoat layer 4 and most of the ink 7 that has been absorbed and retained in the ink absorption layer 3. This figure shows that an inkjet printer transfers ink 8 to visualize information recording. The ink used in the inkjet printing method is not particularly limited, and any ink currently in use or developed can be used.

In the information recording card obtained in this way, the ink is absorbed and retained inside the card at the same time as recording, and does not remain on the card surface, so no fixing means is required after recording, and the image is durable. It is characterized by extremely excellent abrasion resistance, solvent resistance, and tamper resistance.

In addition, the slippery layer of the present invention is also effective against long-term and harsh use of cards, such as when cards are passed through automatic ticket gates many times like magnetic commuter passes, and is free from dirt and mechanical wear. It exhibits an extremely excellent effect on.

Of course, this information recording card can be pre-printed with desired pictures, characters, and background patterns depending on the purpose of use. Furthermore, for applications in which magnetic recording is used in addition to visual images as input information, an information recording card may be provided with a part of the base or a magnetic recording layer.

Next, an example will be explained.

Example 1 2 parts (weight ratio,
Same hereafter) Polyurethane resin (Nippon Polyurethane Co., Ltd.)
Polyester polyol/isocyanate type) 4 parts, methyl ethyl ketone 8 parts, triene 2
The mixed solution consisting of 100% of the total amount was stirred for about 20 minutes using a screw-agitating disperser, and the coating solution was uniformly dispersed and then applied using a roll coater and dried to form an ink absorbing layer. The film thickness was 20μ. On top of that, a mixed solution consisting of 7 parts of powdered talc (average particle size 3μ), 1 part of polyurethane resin, 8 parts of methyl ethyl ketone, and 2 parts of toluene was stirred for about 10 minutes using a screw-type stirring disperser to uniformly disperse the coating liquid. It was coated using a roll coater and dried to form a slippery layer with a thickness of 4 μm. This was cut into a predetermined size and made into a card. Insert this card into the wired impact printer,
A clear penetration image was created by impact printing through a commercially available nylon cloth carbon ribbon.
Immediately after recording, even if I strongly rubbed the surface of the card with my finger, the ink did not disappear or run. Although this card passed through the magnetic information reading head and its transport system 2000 times, the card was not damaged or
There was no staining at all, and there was no deterioration such as erasure of recorded images.

Example 2 8 parts of calcium carbonate powder (manufactured by Shiroishi Calcium Co., Ltd.) was placed on a 700μ thick white polyvinyl chloride sheet,
A mixture of 1 part of polyester resin (manufactured by Toyobo Co., Ltd.), 0.2 parts of nitrocellulose (manufactured by Daicel), 15 parts of methyl ethyl ketone, and 15 parts of toluene was kneaded in a ball mill for about 4 hours, and then the coating liquid was mixed with a roll coater machine. The ink absorption layer was formed by coating and drying. Furthermore, a liquid mixture consisting of 2 parts of boron nitride powder (manufactured by Denki Kagaku Kogyo Co., Ltd.), 1 part of nitrocellulose, 15 parts of isopropyl alcohol, and 3 parts of toluene was further stirred for about 1 hour using a screw-type stirring disperser. The uniformly dispersed coating liquid was applied using a gravure coater and dried to form a slippery layer with a thickness of 3 μm. This was cut into a predetermined size and made into a card. When this card was attached to an inkjet printer and printed, a clear penetration image was formed. Immediately after recording, even if I strongly rubbed the surface of the card with my finger, the ink did not disappear or run.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a configuration diagram of an information recording card of the present invention, FIG. 2 is an explanatory diagram showing a method using impact printing, and FIG. 3 is an explanatory diagram showing a method using inkjet printing. It is. DESCRIPTION OF SYMBOLS 1... Information recording card, 2... Substrate, 3... Ink absorbing layer, 4... Slippery layer, 5... Ink ribbon, 6, 7, 8... Ink.

Claims (1)

[Claims] 1. An ink absorption layer with a thickness of 10 to 30 μm that absorbs and retains information recording ink is provided on the card base, and a slipping layer of 2 to 10 μm that allows the ink to pass through and prevents background smearing is further provided on the card base. The ink absorption layer is made of a pigment having a particle size of 0.5 to 5μ and a resin that disperses and binds the pigment, and the composition ratio of the pigment to the resin is 1/3 to 4/1 by weight. The active layer is composed of solid lubricant particles with a particle size of 0.5 to 10μ and a resin that disperses and binds the solid lubricant particles, and the composition ratio of the solid lubricant particles to the resin is 2/1 to 20 by weight. An information recording card characterized by being /1.