JP6765087B2 - Fabric ribbon for dot impact printers - Google Patents

Description

The present invention relates to a fabric ribbon for a dot impact printer.

Dot impact printers have been widely used in recorders, time card recorders, financial terminals, etc. because of their high operational stability and excellent maintainability such as the need to replace supplies such as fabric ribbons less frequently. There is.

In this way, among various usage methods, especially when used in a time card recorder or a financial terminal, a recorded medium such as a time card or a passbook is repeatedly inserted into the insertion slot of the time recorder or the financial terminal each time it is used. Printing is performed after being transported to a predetermined position of the dot impact printer built in by the rubber roll for transport, and then the rubber roll for transport transports the same transport path in the opposite direction as at the time of insertion and discharges from the insertion port. Will be done. In a time card recorder or financial terminal having a printing mechanism that repeatedly prints on the same recorded medium and then inserts and ejects with a rubber roll for transport, the recorded medium is recorded when it is inserted and ejected. When the print surface of the medium comes into contact with the transport rubber roll, ink adheres to the transport rubber roll from the print surface, and recording is performed from the transport rubber roll to which the ink adheres when the recording medium is ejected or when printing is performed next time. There was a problem that the ink was re-transferred to the medium and became dirty.

Furthermore, in recent years, ethylene-propylene-diene ternary copolymer (EPDM) -based rubber, which has excellent heat resistance and weather resistance and is inexpensive, has been changed from urethane-based rubber, which has been commonly used as rubber for transporting rubber rolls of printers. The ones that use the rubber are becoming more and more popular. However, while EPDM rubber has the above-mentioned excellent properties, it has a weakness of being inferior in oil resistance. Therefore, when ink adheres to the rubber roll for transporting a printer in a financial terminal or the like as described above, it is contained in the ink. The outer diameter of the rubber roll for transport increases as the oil gradually permeates into the rubber roll for transport and the rubber swells. As a result, an error occurs in the transport position of the recording medium, and printing should be performed originally. The problem of printing problems such as printing in a place different from the place where the printing was done has come to occur frequently.

A method for preventing ink retransfer by a transport rubber roll has been proposed in Patent Document 1 and the like, but it is for a transport rubber roll made of urethane rubber, and is a transport rubber roll made of EPDM rubber as in the present invention. In the above, it was necessary to solve not only the problem of ink retransfer but also the problem of printing defects caused by the swelling of the transport rubber roll by the oil agent contained in the ink.

JP-A-8-156403

The present invention has been made in view of such a situation, and in a dot impact printer using EPDM rubber for a transport rubber roll, there is little ink retransfer and printing defects due to swelling of the transport rubber roll due to an oil agent. The main problem is to provide a fabric ribbon for a dot impact printer impregnated with an ink that is less likely to generate ink.

In order to solve these problems, the present inventor is an ink for a dot impact printer composed of at least a colorant, a surfactant, an oil agent, and a resin, and the main component of the oil agent is a medium chain fatty acid triglyceride. Further, they have invented a fabric ribbon for a dot impact printer in which a resin is impregnated with an ink using a thermoplastic elastomer.

If the fabric ribbon for a dot impact printer of the present invention is used, in a dot impact printer using EPDM rubber for a rubber roll for transfer, printing ink adheres to the rubber roll for transfer, and the ink is further transferred to a different place on the printing medium. Retransfer is suppressed, and even if ink adheres to the transport rubber roll, the transport rubber roll does not easily swell due to the oil in the ink, so printing defects caused by the swelling of the transport rubber roll can be suppressed. It will be possible.

The ink used for the fabric ribbon in the present invention is at least a colorant such as a dye or a pigment, a surfactant that functions to disperse the pigment and stabilize the paint, and an oil agent that is a main component of the ink vehicle, and the ink is applied to paper or the like. It is composed of a resin that serves as a binder component that forms a coating film when transferred.

Furthermore, various inorganic fillers and organic fillers, organic acids such as fatty acids as dye dissolving agents, various dispersion aids, various lubricants, various additives, etc. are added as ink raw materials according to the required quality and application requirements. However, it is not limited to these.

As the colorant used for the ink of the fabric ribbon of the present invention, various dyes and various pigments can be used. The fabric ribbon ink in the present invention may be a dye-based ink using only a dye, a pigment-based ink using only a pigment, or a dye-based ink using both a dye and a pigment.

As the dye used for the fabric ribbon ink of the present invention, one or more dyes such as niglosin dye, methyl violet, and oil black can be used.

When a dye is used as a colorant for ink, it is common to use various long-chain fatty acids such as oleic acid and stearic acid as a dye-dissolving agent, and to dissolve the dye in the long-chain fatty acid. Since EPDM rubber has poor resistance to organic acids such as fatty acids, it is preferable to keep the amount of dye dissolving agent as small as possible when using it in ink, and the amount of dye dissolving agent added is 0 to 0 for the entire ink, although it is not particularly limited. It is preferable to keep it in the range of 20% by mass.

As the pigment used for the ink of the fabric ribbon of the present invention, one or more kinds of inorganic pigments such as carbon black and organic pigments such as aniline black, phthalocyanine blue and dysazo yellow can be used.

The amount of the colorant added to the ink of the fabric ribbon of the present invention is not particularly limited, but is preferably in the range of 10 to 40% by mass, more preferably in the range of 20 to 30% by mass of the entire ink. More preferred. When the amount of the colorant added is within the above range, it is easy to obtain an ink having appropriate print density and ink fluidity and less likely to reduce the print life.

As the surfactant used for the ink of the fabric ribbon of the present invention, various known surfactants can be used. The surfactant not only plays a role of dispersing the pigment and imparting stability of the paint as a wetting agent / dispersant for improving the wetting / dispersing property of solid fine particles such as pigments, but also has a viscosity depending on the selection of the surfactant. It also serves as a modifier, dye solubilizer, compatibilizer, solubilizer, and antistatic agent.

Examples of the surfactant that can be used in the fabric ribbon ink of the present invention include various carboxylate-type surfactants, various sulfonate-type surfactants, and various sulfate ester-type surfactants as anionic surfactants. Activators, various phosphate ester salt-type surfactants, etc. can be used. As the cationic surfactant, an alkylamine salt type surfactant, a quaternary ammonium salt type surfactant and the like can be used in the fabric ribbon ink of the present invention. As the amphoteric surfactant, a carboxybetaine type surfactant, a 2-alkylimidazoline inducible type surfactant, a glycine type surfactant, an amine oxide type surfactant and the like can be used in the fabric ribbon ink of the present invention. Nonionic surfactants include ester-type surfactants such as glycerin fatty acid ester, sorbitan fatty acid ester and sucrose fatty acid ester, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether and polyoxyethylene polyoxyporopylene glycol. Ether-type surfactants, ester ether-type surfactants such as fatty acid polyethylene glycol and fatty acid polyoxyethylene sorbitan, and alkanolamide-type surfactants such as fatty acid alkanolamide can be used in the fabric ribbon ink of the present invention. The above-mentioned surfactant can be used alone or in combination of two or more depending on the intended use, and the usable surfactant is not limited to the above-mentioned surfactant.

The amount of the surfactant added to the ink of the fabric ribbon of the present invention is preferably in the range of 5 to 40% by mass, more preferably in the range of 10 to 30% by mass of the entire ink. When the amount of the surfactant added is within the above range, it is possible to obtain an ink having excellent pigment dispersion and coating stability.

Depending on the type of surfactant used for the ink of the fabric ribbon of the present invention, there are some that have a great influence on the swelling of EPDM rubber or the shrinkage due to the elution of components in EPDM rubber. Therefore, when using EPDM as much as possible. It is necessary to consider in advance the use of a type of surfactant that does not swell or shrink the rubber, and it is preferable to keep the amount added to the minimum necessary.

The oil agent in the ink of the fabric ribbon of the present invention is a main component of a vehicle that has a great influence on the viscosity, viscosity, storage stability, dispersibility of pigments and dyes, etc. of the ink. The amount of the ink added is not particularly limited, but in general, it is often added in an amount of about 30 to 70% by mass of the entire ink.

The oil used in the ink of general fabric ribbons is a liquid, hydrophobic and non-drying substance at room temperature, and specifically, various known vegetable oils such as olive oil and various kinds are typical. Examples include various mineral oils such as animal oils and liquid paraffins, various polyα-olefin synthetic oils, and various ester synthetic oils such as monoesters, diesters, and polyol esters such as fatty acid triglycerides. One type or two or more types of oils are selected and used.

As a result of diligent research by the present inventors, it is possible to suppress swelling of EPDM rubber due to ink by using medium-chain fatty acid triglyceride as the main component of the oil agent as the oil agent used for the ink of the fabric ribbon of the present invention. found.

The medium-chain fatty acid triglyceride used as an oil agent for the ink for fabric ribbon of the present invention refers to an oil in which glycerin and three medium-chain fatty acids having 8 to 12 carbon atoms are ester-bonded. Medium-chain fatty acid triglyceride is a type of fatty acid ester that is also abundant in natural fats and oils such as coconut oil and palm oil, but if it is left as it is, it also contains a lot of impurities and triglycerides consisting of long-chain fatty acids, resulting in variations in performance. In addition, it is not easy to use because it is solid at room temperature or has very poor fluidity. Therefore, as the oil agent used in the present invention, the ratio of the medium-chain fatty acid composition to the total fatty acid composition of the fatty acid triglyceride from natural coconut oil or the like is It is preferable to use a purified medium-chain fatty acid triglyceride oil purified to be at least 90% or more, a synthetic medium-chain fatty acid triglyceride oil in which the medium-chain fatty acid triglyceride chemically synthesized from glycerin and the medium-chain fatty acid is 100%.

The component of the medium-chain fatty acid triglyceride used in the ink for fabric ribbon of the present invention is not particularly limited, but more preferably, a medium-chain fatty acid triglyceride consisting of at least one of caprylic acid capric acid triglyceride or caprylic acid capric acid lauric acid triglyceride. It is preferable to use it, and it is more preferable to use caprylic acid triglyceride. By using these medium-chain fatty acids, it is possible to produce a fabric ribbon having less swelling of EPDM rubber, good pigment dispersibility of the ink and good stability of the ink, and a long printing life.

The viscosity of the medium-chain fatty acid triglyceride used in the ink of the fabric ribbon of the present invention is not particularly limited and can be used as long as it is liquid at room temperature and has appropriate fluidity, but it can be used by a vibration viscometer of JIS Z8803 (2011). The viscosity at 25 ° C. is preferably in the range of 1 to 80 mPa · s, and more preferably in the range of 1 to 40 mPa · s. When the viscosity of the medium-chain fatty acid triglyceride is within the above range, the produced ink has an appropriate viscosity, the fluidity of the ink is ensured, and it becomes easy to produce a fabric ribbon having a long printing life.

The amount of the medium-chain fatty acid triglyceride used in the ink of the fabric ribbon of the present invention is not particularly limited, but it is preferably added in an amount of 30 to 70% by mass, more preferably 40 to 60% by mass, based on the total amount of the ink. It is more preferable to be done. At this time, it is necessary that at least 50% by mass or more of the medium-chain fatty acid triglyceride is added to the entire oil preparation, more preferably 90% by mass or more, and most preferably the entire amount of the oil preparation is the medium-chain fatty acid triglyceride. .. When the amount of the medium-chain fatty acid triglyceride added to the ink is within the above range, it becomes easy to prepare a fabric ribbon having less swelling of the EPDM rubber, the ink having an appropriate viscosity, and a long printing life.

The resin used for the ink of general fabric ribbons improves the print physical properties by forming a coating film as a binder on the surface layer of the printing medium, and retransfers the ink from printing to other papers and rubber rolls for transportation. It is effective in suppressing the ink. The amount of the ink added is not particularly limited, but in general, about 0.1 to 30.0% by mass of the entire ink is often added. When resin is not added to the ink of the fabric ribbon, the vehicle component of the ink is non-drying oil, so when the ink does not penetrate sufficiently into the paper to be printed immediately after printing, the ink is retransferred. Problems are particularly likely to occur, and similarly, the problem of ink retransfer is likely to occur when printing on paper having poor ink permeability.

As a result of diligent research by the present inventors, it has been found that the problem of ink retransfer can be significantly suppressed by using a thermoplastic elastomer as the resin used for the ink of the fabric ribbon of the present invention. did.

As the thermoplastic elastomer used for the ink of the fabric ribbon of the present invention, various known thermoplastic elastomers can be used, for example, amide-based thermoplastic elastomers, ester-based thermoplastic elastomers, olefin-based thermoplastic elastomers, etc. Among styrene-based thermoplastic elastomers, urethane-based thermoplastic elastomers, and various other thermoplastic elastomers, thermoplastic elastomers that are soluble in the medium-chain fatty acid triglyceride oil of the present invention can be used.

By adding a small amount of thermoplastic elastomer to the ink, the ink becomes gelled and the viscosity becomes very high. High-viscosity ink has lower fluidity than low-viscosity ink, so the rate of wetting with the surface of paper, transport rubber rolls, etc. is slower, and as a result, printing and transport rubber rolls come into instantaneous contact. It is considered that the problem of ink retransfer that occurs at that time is less likely to occur in the ink having a high viscosity.

The thermoplastic elastomer used in the present invention is a copolymer of at least 3 blocks composed of styrene and a specific diene such as butadiene or isoprene, and the two hard blocks at both ends are polystyrene. It is particularly preferred to use a styrene-based thermoplastic elastomer (TPS) in which one or more soft blocks consist of polydiene or hydride polydiene.

Polystyrene-based thermoplastic elastomers are used as raw materials for adhesives and pressure-sensitive adhesives for various materials. They have little tack on their own, and once bonded, they are resistant to other materials unless heat and pressure above a certain level are applied. It has the property of being difficult to reattach and reattach. Therefore, when a styrene-based thermoplastic elastomer is used as a raw material for ink, not only the adhesive strength of the ink to various materials is improved, but also after the transferred ink forms a coating film, it becomes another substance. On the other hand, it has an excellent property that it is difficult to re-adhere or re-adhere.

The type of styrene-based thermoplastic elastomer that can be used in the present invention is not particularly limited, and various known styrene-based thermoplastic elastomers such as SBS resin, SEBS resin, SEPS resin, and SIS resin can be appropriately selected and used.

The content of the styrene component in the styrene-based thermoplastic elastomer in the present invention is not particularly limited, but is preferably 10 to 40% by mass, preferably 20 to 40% by mass. If it is within the range of the previous term, it is easily dissolved in the oil agent, and the printed coating film exhibits appropriate adhesiveness and adhesiveness in a wide range from paper to film material.

In the present invention, the amount of the styrene-based thermoplastic elastomer added to the ink is preferably in the range of 0.3 to 10.0% by mass, and more preferably in the range of 0.5 to 7.0% by mass. , 1.0 to 5.0% by mass, most preferably. If the amount of the styrene-based thermoplastic elastomer added to the ink is less than 0.3% by mass, the effect of suppressing the retransfer of the ink is less likely to appear, and conversely, if the amount added exceeds 10.0% by mass, the ink Since the viscosity of the ink is very high, the printing life tends to decrease sharply. A study by the inventor has revealed that the larger the amount of styrene-based thermoplastic elastomer added to the ink, the higher the effect of suppressing the retransfer of the ink tends to be.

The following is a summary of typical ink compounding examples used in the fabric ribbon for the dot impact printer of the present invention described above.
<Component><Mass%>
Colorants (pigments / dyes) 10-40
Surfactants (dispersants, wetting agents, viscosity modifiers) 5-40
Oil (medium chain fatty acid triglyceride) 30-70
Dye solubilizer (organic acid, etc.) 0 to 20
Resin (thermoplastic elastomer) 0.3 to 10.0
Various additives 0-5

The ink used for the fabric ribbon of the present invention is produced by kneading and dispersing the above-mentioned ink-blended raw materials with a three-roll mill or the like. The viscosity of the ink impregnated in the fabric ribbon is preferably within a certain range, and if the viscosity is too low, the paper may become dirty even if the fabric ribbon and the paper come into contact with each other, or the ink transferability is good. There is a tendency that the printing life is too short and ink re-transfer is likely to occur. On the other hand, if the viscosity of the ink is too high, the fluidity of the ink will be too poor, causing ink unevenness depending on the location of the fabric such as the printed part of the fabric ribbon and the non-printed part, resulting in uneven printing density. And problems such as shortened printing life tend to occur. The ink produced from these things preferably has a viscosity in a certain range, and the viscosity of the ink used in the present invention is 500 to 6000 mPa · s at 25 ° C. according to a vibration viscometer of JIS Z8803 (2011). It is preferably in the range, and more preferably in the range of 1000 to 5000 mPa · s. If the viscosity of the ink is within the above range, retransfer of the ink is unlikely to occur, the ink has an appropriate viscosity, the fluidity of the ink is ensured, and it is easy to create a fabric ribbon having a long printing life. Become.

The fabric ribbon in the present invention is completed by impregnating the fabric for fabric ribbon with the above-mentioned ink by a coating machine. The fabric for the fabric ribbon is not particularly limited, and for example, a plain weave cloth made of various synthetic fibers such as nylon and polyester can be used, but it is particularly preferable to use a plain weave cloth made of nylon 66 having excellent mechanical strength. The basis weight of the fabric for the fabric ribbon is not particularly limited, but it is generally preferable to use a fabric of 40 to 80 g / m ² .

In the present invention, the amount of ink impregnated in the fabric is not particularly limited, but the amount of ink impregnated per unit area is preferably in the range of 6 to ²⁰ g / m ² . If the amount of ink impregnated is within the above range, it is possible to obtain a fabric ribbon having an appropriate print density and life, and which does not cause problems such as background stains.

Next, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to the Examples.

<Example 1>
Ink formulation 1 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 1)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 47.0
(100% caprylic acid triglyceride)
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer A (styrene content 30% by mass) 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Example 2>
The ink formulation 2 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 2)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 50.0
(100% caprylic acid triglyceride)
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer A (styrene content 30% by mass) 2.0
・ Carbon 10.0
・ Organic pigment 18.0

<Example 3>
Ink formulation 3 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 3)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 51.5
(100% caprylic acid triglyceride)
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer A (styrene content 30% by mass) 0.5
・ Carbon 10.0
・ Organic pigment 18.0

<Example 4>
The ink formulation 4 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 4)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 45.0
(100% caprylic acid triglyceride)
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer A (styrene content 30% by mass) 7.0
・ Carbon 10.0
・ Organic pigment 18.0

<Example 5>
The ink formulation 5 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 5)
Raw material component mass%
・ Refined medium-chain fatty acid triglyceride oil 47.0
(Caprylic acid capric acid lauric acid triglyceride 90%)
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer A (styrene content 30% by mass) 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Example 6>
The ink formulation 6 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 6)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 47.0
(100% caprylic acid triglyceride)
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer B (styrene content 18% by mass) 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Example 7>
The ink formulation 7 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 7)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 47.0
(100% caprylic acid triglyceride)
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer C (styrene content 20% by mass) 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Comparative example 1>
The ink formulation 8 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 8)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 52.0
(100% caprylic acid triglyceride)
・ Surfactant 20.0
・ Carbon 10.0
・ Organic pigment 18.0

<Comparative example 2>
The ink formulation 9 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 9)
Raw material component mass%
・ Poly α-olefin synthetic oil 47.0
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer A (styrene content 30% by mass) 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Comparative example 3>
The ink formulation 10 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 10)
Raw material component mass%
・ Octyl oleate 47.0
・ Surfactant 20.0
-Styrene-based thermoplastic elastomer A (styrene content 30% by mass) 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Comparative example 4>
The ink formulation 11 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 11)
Raw material component mass%
・ Synthetic medium chain fatty acid triglyceride oil 47.0
(100% caprylic acid triglyceride)
・ Surfactant 20.0
・ Resol type phenol resin 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Comparative example 5>
The ink formulation 12 shown below is kneaded and dispersed with a three-roll mill to create an ink, and the ink is further applied by a painting machine to a width of 13 mm and a grain of 55 g / m ^{2 for} a nylon 66 plain weave ribbon of 11 g / m. ^A fabric ribbon was prepared by impregnation coating with an amount of ² .
(Ink formulation 12)
Raw material component mass%
・ Dioctyl adipate 47.0
・ Surfactant 20.0
・ Resol type phenol resin 5.0
・ Carbon 10.0
・ Organic pigment 18.0

<Ink immersion storage test of EDPM rubber transport rubber roll>
Approximately 100 cc of each of the various inks prepared in Examples and Comparative Examples is weighed in a container, and the entire EPDM rubber transport rubber roll of the dot impact printer in which the fabric ribbon of the present invention is used is completely immersed in the ink at 60 ° C. Store in a state of being allowed to stand for 400 hours in the environment of. Based on the results of measuring the outer diameter of the EDPM rubber transport rubber roll before and after the ink immersion storage, the outer diameter change rate of the EDPM rubber transport rubber roll for each ink was determined. The outer diameter change rate (%) of the EDPM rubber transport rubber roll is calculated by the following equation.
"Rate of change in outer diameter of EDPM rubber transport rubber roll (%) = ((Outer diameter of EDPM transport rubber roll after ink immersion storage)-(Outer diameter of EDPM transport rubber roll before ink immersion storage)) ÷ (Outer diameter of EDPM transport rubber roll before ink immersion storage) x 100 "
From the results of printing tests so far, if the outer diameter change rate of the transport rubber roll of the dot impact printer is in the range of 0 to 5.0%, printing defects due to the swelling of the transport rubber roll will occur at all. However, if the outer diameter change rate exceeds 5.0% and 7.0% or less, printing defects due to swelling of the rubber roll for transportation may occur slightly, but it can withstand use. It has been found that when the outer diameter change rate exceeds 7.0%, printing defects due to swelling of the transport rubber roll tend to occur frequently.

<Viscosity of oil and ink>
The viscosities of the oil and the ink were measured at 25 ° C. using a tuning fork type vibration viscometer SV series manufactured by A & D Co., Ltd., which corresponds to JIS Z8803 (2011).

<Evaluation of ink retransfer>
The fabric ribbons produced in Examples and Comparative Examples were loaded into a ribbon cassette as a Mobius ring, and the ribbon cassette was mounted on a 24-pin wire dot printer for print evaluation using EDPM rubber for a rubber roll for transport. This print evaluation printer is a printing operation in which when a piece of high-quality paper is fed, the character "*" is printed on the piece of paper for the entire width of one line, and then the piece of paper is ejected. Is set to do. A sample for evaluation of ink retransfer was prepared by continuously printing a sheet of single-cut paper 24 times repeatedly using the above-mentioned printer for print evaluation. It should be noted that the cut sheet was initially used in an unused and unprinted state, and printing was started, and the printing operation was continuously performed 24 times without any time until printing was completed. In addition, the printer used for evaluation has a structure in which the printing part and the rubber roll for transport pass through and contact each other once when feeding and discharging the cut sheet.
The degree of dirt on the upper end non-printing area of the cut sheet paper through which the transport rubber rolls passed and contacted after printing was visually observed and evaluated according to the following evaluation criteria.
(Evaluation criteria)
A: Ink retransfer can hardly be visually confirmed.
B: Retransfer of ink can be visually confirmed, albeit slightly.
C: Ink retransfer is visually observed.
D: The stain due to ink retransfer is severe.

<Evaluation of print life>
The fabric ribbon prepared in Examples and Comparative Examples was used as a Mobius ring having a ribbon length of 38 m, and was loaded into a ribbon cassette to carry out a printing test. Printing was performed on the stock form with a 24-pin wire dot printer, and the PCS print density (A filter) was measured using a densitometer PCM-II manufactured by Macbeth. The print life was evaluated by measuring the number of characters that could be printed before the PCS print density (A filter) reached 0.40, and using the following evaluation criteria.
(Evaluation criteria)
A: 1.5 million characters or more B: 1.3 million characters or more and less than 1.5 million characters C: 1 million characters or more and less than 1.3 million characters D: less than 1 million characters

Table 1 shows various characteristic data and various evaluation results of the fabric ribbons of Examples and Comparative Examples of the present invention. (* In the table, medium-chain fatty acid triglyceride oil is abbreviated as MCT, triglyceride is abbreviated as TG, and styrene-based thermoplastic elastomer is abbreviated as TPS.)

From the results in Table 1, as shown in Examples 1 to 7, the resin is composed of at least a colorant, a surfactant, an oil agent, and a resin, the main component of the oil agent is a medium-chain fatty acid triglyceride, and the resin is a thermoplastic elastomer. By using the fabric ribbon impregnated with the used ink, the outer diameter change rate after the oil immersion storage test of the EPDM rubber transport rubber roll of the dot impact printer is as small as 5.0% or less, and the ink is retransferred. It can be seen that problems are unlikely to occur and the printing life is good.

From the results of Comparative Example 1, when a fabric ribbon impregnated with an ink in which medium-chain fatty acid triglyceride is used as the main component of the oil agent but no resin is added is used, there is no problem in printing life and it is made of EPDM rubber. It can be seen that the retransfer of the ink is clearly deteriorated, although the printing defect caused by the swelling of the transport rubber roll due to the oil agent does not occur.

When the fabric ribbon impregnated with the ink prepared by replacing the synthetic medium-chain fatty acid triglyceride oil of Example 1 with another oil agent as in Comparative Example 2 and Comparative Example 3, the printing life is not a problem and the ink is regenerated. Although the transfer problem does not occur, the rate of change in the outer diameter of the transport rubber roll due to the swelling of the EPDM rubber transport rubber roll exceeds 7.0%, so that the printing defect is caused by the swelling of the transport rubber roll due to the oil agent. Is likely to occur.

As in Comparative Example 4, when a fabric ribbon impregnated with an ink prepared by using the resole-type phenol resin exemplified in the prior art document 1 as a resin is used instead of the styrene-based thermoplastic elastomer of Example 1. There is no problem with the printing life, and there is no printing problem caused by the swelling of the EPDM rubber transport rubber roll due to the oil agent, but it was found that the problem of ink retransfer was clearly worsened as compared with Example 1. It was.

As in Comparative Example 5, when a fabric ribbon impregnated with an ink prepared by using the resole-type phenol resin exemplified in the prior art document 1 as a resin and dioctyl adipate as an oil agent is used, there is a problem in printing life. However, since the outer diameter change rate of the transport rubber roll due to the swelling of the EPDM rubber transport rubber roll exceeds 7.0%, printing defects due to the swelling of the transport rubber roll due to the oil agent are likely to occur. Furthermore, the ink retransfer was also bad.

The fabric ribbon for a dot impact printer in the present invention can be used not only for a device including a printer that repeatedly uses a printed medium such as a time clock or a financial terminal, but also for various dot impact printers in general.

Claims (4)

It is composed of at least a colorant, a surfactant, an oil agent, and a resin, and the main component of the oil agent is a fatty acid triglyceride composed of a fatty acid having 8 to 12 carbon atoms and glycerin , and the resin is impregnated with an ink using a thermoplastic elastomer. Fabric ribbon for dot impact printers. The fabric ribbon for a dot impact printer according to claim 1, wherein the fatty acid triglyceride composed of a fatty acid having 8 to 12 carbon atoms and glycerin is composed of at least one of caprylic acid capric acid triglyceride and caprylic acid lauric acid triglyceride. The fabric ribbon for a dot impact printer according to claim 1 or 2, wherein the thermoplastic elastomer is a styrene-based thermoplastic elastomer. The fabric ribbon for a dot impact printer according to any one of claims 1 to 3, wherein the viscosity of the ink at 25 ° C. by a vibration viscometer of JIS Z8803 (2011) is in the range of 500 to 6000 mPa · s.