JP2001347716A - Printer for linerless print sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer having a long lifetime and an easy-to-manufacture roll in which a linerless print sheet can be fed out in stable state from a roll thereof at the time of printing, printing can be resumed stably even after long term interruption and such good print characteristics can be sustained for a long term. SOLUTION: The printer comprises a print mechanism 2 for forming ink information 26 on the surface of a linerless print sheet 1 having an adhesive layer 12 formed on the rear surface of a basic material 11 to be printed, and a carry roll 21 for feeding out the sheet 1 from a roll 13 thereof and carrying the sheet 1. Ink information 26 is formed on the sheet 1 by means of the print mechanism 2 while carrying the sheet 1 through the roll 22. The roll 21 carries the sheet 1 while touching the adhesive layer 12 and at least the surface of the roll 21 is formed of a silicon rubber containing silicon oil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing mechanism for forming ink information on the surface of a linerless printing sheet provided with an adhesive layer on the back surface of a substrate to be printed, and winding the sheet into a roll. Transport means for feeding out and transporting the sheet from the wound body, wherein the ink information is formed by the printing mechanism while the sheet is transported by the transport means.

[0002]

2. Description of the Related Art A linerless printing sheet (hereinafter sometimes simply referred to as a sheet) having an adhesive layer for bonding an adherend on the back surface of a substrate to be printed is stored in a compact wound form. A printing apparatus capable of continuously forming a print sheet such as a label while feeding the sheet from the wound body is known. Further, it has been a long time since the adhesive layer does not have a protective cover such as a separator.
The reason for this is that the protective cover such as a separator must be finally peeled off from the adhesive layer and discarded, which requires extra work for peeling off or generates unnecessary products such as dust. It is because.

On the other hand, in order to convey a linerless printing sheet without a protective cover, it is necessary to devise a material of a conveying roll (corresponding to a conveying means) which comes into contact with the adhesive layer. That is, in order to transport the sheet smoothly, it is necessary to use a material that does not easily adhere to the surface of the roll and the adhesive layer of the sheet. For this reason, conventionally, as a transport roll that comes into contact with the adhesive layer of the sheet, a metal roll whose surface is baked and coated with silicone or fluororesin,
Alternatively, a roll formed of silicone has been used.

[0004]

In the case of the roll according to the prior art described above, the sheet can run stably when the printing process is continuously performed. However, once the printing process is stopped and the conveyance stop state continues for a while, the printing substrate cannot be moved forward because the substrate to be printed is caught in the conveyance roll due to an increase in the adhesive force when the printing process is restarted. However, there is a problem of poor practicality.

[0005] Further, in a metal roll coated with a fluororesin or the like in the conventional printing apparatus, if the releasability of the fluororesin or the like is reduced, the adhesive force between the sheet and the adhesive layer is increased. That is, if the baking coat layer is worn away quickly, the sheet cannot be transported, and the transport life is shortened. Further, there is also a problem that the production efficiency is low (the production cost is high) because the production of the metal roll having the baking coat requires many steps.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to perform a printing process while sequentially feeding a sheet from a roll of a linerless printing sheet in a stable state and transporting the sheet. Equipped with rolls that can continuously and stably perform print processing while feeding out and transporting in the same way as before the interruption even if resumed after interruption, and can maintain such good printing characteristics for a long time, have a long life, and be easy to manufacture To provide a printing device.

[0007]

According to the present invention, there is provided a printing apparatus for a linerless printing sheet according to the present invention, wherein ink information is provided on a surface of the linerless printing sheet provided with an adhesive layer on a back surface of a substrate to be printed. A printing mechanism for forming a sheet, and conveying means for feeding the sheet from a roll wound around a roll and conveying the sheet. The conveying mechanism conveys the sheet, and the printing mechanism conveys the ink information. In the printing apparatus for a sheet for linerless printing, the conveying means is configured to convey the sheet in a state of being in contact with the adhesive layer, and at least the surface of the sheet contains silicone oil. It is characterized by being formed of silicone rubber.

According to this structure, the surface of the conveying means such as a roll is formed of silicone rubber containing silicone oil.
Even if the pressure-sensitive adhesive layer of the linerless printing sheet and the conveying means have been in contact with each other for a long time, the adhesive force does not increase. In addition, as a configuration of the transport means,
The entire conveying means may be formed of silicone rubber, or only the surface of the conveying means may be formed of silicone rubber. In any case, it suffices that the surface of the conveying means that comes into contact with the adhesive layer is configured as described above.

As described above, according to the configuration of the present invention, the printing process can be performed while the sheet is sequentially fed out and conveyed from the roll of the linerless printing sheet in a stable state, and the printing process is resumed after a long-term interruption. As in the case before the interruption, the printing process can be continuously and stably performed while being fed out and conveyed. Therefore, such good printing characteristics can be maintained for a long period of time, and the life can be prolonged. In addition, since the silicone rubber is merely impregnated with silicone oil, it can be said that the production of the transporting means is easier and the production efficiency is superior to that in which the silicone rubber is baked and coated.

[0010] As an embodiment of the present invention, the silicone
The kinematic viscosity of the oil is from 300 to 100,000 mm ^Two / S (25 ° C)
Preferably, there is. A silicone oil with a kinematic viscosity in this range
Bloom properly by selecting the file
Can be fed out of linerless printing sheet
Can be maintained.

In another preferred embodiment of the present invention, a printing method in the printing mechanism is selected from any one of a fusion type thermal transfer type, a sublimation type thermal transfer type, an ink jet type, and a thermal type. Using such a versatile printing method, a printing sheet such as a label can be continuously formed in a stable state.

Further, the linerless printing sheet, especially the substrate to be printed, has heat resistance, water resistance, solvent resistance, weather resistance, etc., depending on the fixing property based on various printing methods and the intended use of the printed matter. Performance can be set appropriately according to the application and can be handled in a wide range. Therefore, the printing sheet can be efficiently and continuously formed by various printing methods excellent in versatility,
In addition, a printing sheet can be issued on the spot using a commercially available thermal transfer printer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A printing apparatus according to the present invention comprises a printing mechanism for forming ink information on the surface of a linerless printing sheet provided with an adhesive layer on the back surface of a substrate to be printed, and a sheet-like printing apparatus. And a transport unit for feeding out the rolled body and transporting the roll, wherein the printing mechanism forms the ink information while transporting the sheet by the transport unit. The conveying means includes a roll for conveying the sheet in contact with the adhesive layer of the sheet, and at least the surface of the roll is formed of silicone rubber containing silicone oil.

A printed label sheet can be obtained by applying ink information to a substrate to be printed of a linerless printing sheet. This linerless printing sheet has an adhesive layer on the back surface of the substrate to be printed, but does not have a protective cover such as a separator for protecting the adhesive layer. By using a linerless printing sheet, it is possible to abolish the removal and removal of protective covers such as separators,
It is possible to prevent generation of unnecessary products due to dusting of the protective cover. In addition, the sheet can be made compact by forming it into a wound body. Furthermore, since a label sheet can be smoothly created on site and there is no need to peel off the protective sheet, the label sheet can be smoothly bonded to an adherend.

<Configuration of Printing Apparatus According to Embodiment> FIG.
A preferred embodiment of the printing apparatus according to the present invention has been illustrated by way of example.
The linerless printing sheet 1 has an adhesive layer 12 on the back surface of a printing substrate 11 formed continuously in a long shape,
This adhesive layer 12 is not provided with a protective cover. In the linerless printing sheet 1, the adhesive layer 12 is wound around a core material 13 a in the form of a roll-shaped wound body 13. While the sheet 1 is sequentially fed out and conveyed from the winding body 13 in the direction of the arrow, the information 26 by ink is given to the surface of the substrate 11 to be printed by the printing mechanism 2 based on the print data. After performing predetermined printing on the surface of the substrate 11 to be printed, the sheet 1 is cut into predetermined dimensions by the cutting mechanism 4 provided on the downstream side of the transport path. Thereby, a printing sheet (label sheet) 14 such as a label can be continuously formed.

The printing mechanism 2 shown in FIG. 1 is a thermal transfer system including a platen roll 21, a thermal head 22 disposed on the platen roll 21, an ink ribbon 23, a delivery reel 24 and a take-up reel 25. Printing mechanism 2 is adopted. Therefore, the platen roll 21 functions as a transport unit that comes into contact with the adhesive layer 12 provided on the back surface of the substrate 11 to be printed. This platen roll 2
In No. 1, at least a surface portion thereof is formed of silicone rubber containing silicone oil.

In the present invention, when the printing process is performed on the linerless printing sheet 1, the sheet 1 provided with the adhesive layer 12 on the back surface of the substrate 11 to be printed as shown in FIG. The sheet 1 is sequentially fed out from the rotor 13. A platen roll 21 having at least a surface portion made of silicone rubber impregnated with silicone oil is used as a transporting means on the side that comes into contact with the adhesive layer 12 of the sheet 1. The ink information 26 is provided by the printing mechanism 2 to the printer.

The platen roll 21 may be formed entirely of silicone rubber, or only its surface portion may be formed of silicone rubber. In any case, it is important that the surface portion is formed of silicone rubber containing silicone oil.

In the present invention, as shown in FIG. 1, a cutting mechanism 4 for cutting the linerless printing sheet 1 that has been subjected to a printing process to a predetermined size can be provided as required. Incidentally, in the example of FIG. 1, a forward feed mechanism 3 including pinch rolls 31 and 32 using a pair of embossing rolls is provided upstream of the cutting mechanism 4.

In the above case, the progressive feeding mechanism 3 can also be a roll of transport means that comes into contact with the adhesive layer 12 of the linerless printing sheet 1. In this case, at least the surface of the roll that comes into contact with the adhesive layer 12 is made of silicone. Made of silicone rubber impregnated with oil. Incidentally, in the progressive feeding mechanism 3 illustrated in FIG. 1, at least the surface of the roll 32 (the lower roll in FIG. 1) in contact with the adhesive layer 12 is formed of silicone rubber impregnated with silicone oil. .

In the example of FIG. 1, the printing mechanism 2 of the thermal transfer system is illustrated, but the thermal transfer system may be a fusion thermal transfer system or a sublimation thermal transfer system. In addition, for example, an appropriate printing mechanism for printing with a heat fixing type or dry type ink, such as an ink jet type printing method, may be employed. Furthermore, a printing mechanism using a heat-sensitive method can be adopted. The progressive mechanism 3 may be a pinch roll type or any other suitable mechanism capable of progressively feeding a linerless printing sheet.

In the present invention, the platen roll 21 as a transporting means that comes into contact with the adhesive layer 12 of the linerless printing sheet 1 is formed at least on a surface portion of silicone rubber impregnated with silicone oil. Similarly, it is preferable that the surface portions of the transfer rolls and guide portions (guide guides and the like) other than those described above are also formed of silicone rubber impregnated with silicone oil.

In the above case, the thickness of the silicone rubber layer is preferably 0.1 mm or more, more preferably 0.5 mm or more, particularly preferably in view of the roll life due to wear of the silicone rubber layer. Is 1 mm or more.
The contact portion can be entirely formed of silicone rubber or the like.

<Regarding Silicone Oil> The silicone oil used in the present invention preferably has a kinematic viscosity of 300 to 100,000 mm ² / s (25 ° C.). If the thickness is less than 30 mm ² / s, the silicone oil rapidly and largely blooms on the surface of the silicone rubber, so that it is difficult to maintain good feeding and transportability.
On the other hand, if the kinematic viscosity exceeds 100,000 mm ² / s, blooming on the surface of the silicone rubber becomes difficult, and no improvement in the feeding-out transportability is observed. In addition, the addition amount of the silicone oil is preferably 2 to 50% by weight.

The adhesive force between the surface of the adhesive layer 12 and the silicone rubber impregnated with silicone oil can be appropriately determined from the viewpoint of the balance between the adhesive force to the conveying means (roll) and the adhesive force to the adherend. . Generally, in consideration of the automatic transportability of the linerless printing sheet 1 when a thermal transfer printer or the like is used, the 180-degree peel adhesion (peeling speed 300 mm / min) to silicone rubber impregnated with silicone oil is considered. Based on the above, preferably 98 mN / 50 mm or less, more preferably 9.8
mN / 50 mm or less, particularly preferably 0.98 mN / 5
It is preferable that the adhesive strength is set to be 0 mm or less.

The silicone rubber layer may be provided on the surface of the conveying means (rolls or the like) by a casting method, a polymer liquid applying method,
It can be performed by an appropriate method such as a lamination method of a sheet or the like. Therefore, in this case, the printing according to the present invention is performed by attaching a silicone rubber layer to a roll that comes into contact with the adhesive layer of the linerless printing sheet and, if necessary, other conveying means in an existing printing apparatus. It can be a device.

As the silicone rubber, those having an appropriate polymer skeleton such as polydimethylsiloxane, polymethylphenylsiloxane, and polydialkylsiloxane can be used. The silicone rubber may be subjected to a cross-linking treatment by an appropriate method such as electron beam irradiation for the purpose of improving abrasion resistance and the like. In addition, the silicone rubber may contain 1 to 10% by weight of a suitable release polymer such as a silicone-based, long-chain alkyl-based, or fluorine-based polymer for the purpose of reducing the adhesive strength.

As the silicone oil of the present invention, for example, one or more suitable polysiloxanes such as polydimethylsiloxane, polymethylphenylsiloxane and polydialkylsiloxane may be used. In addition, silicone oils are amino-modified, epoxy-modified, carboxyl-modified, carbinol-modified, methacryl-modified, mercapto-modified, phenol-modified and other reactive silicone oils and polyether-modified, methylstyryl-modified, alkyl-modified, higher fatty acid ester-modified, It may be a non-reactive silicone oil such as a higher alkoxy-modified one, may have a functional group, or may be a modified one.

The method of adding silicone oil to the silicone rubber includes a method of adding the silicone oil to the silicone rubber before crosslinking and blending the silicone rubber, and a method of immersing the silicone rubber after crosslinking in the silicone oil and absorbing it.

On the other hand, a portion of the transporting means or the like (a transport guide or the like) in the printing apparatus which may come into contact with the adhesive layer of the linerless printing sheet is adhered to the adhesive layer so that the linerless printing sheet can be transported smoothly. Appropriate measures may be taken to prevent hindrance or the like.

The printing apparatus according to the present invention can be provided with a cutting mechanism 4 as shown in FIG. 1 if necessary.
The cutting mechanism 4 may be any mechanism that cuts the linerless printing sheet 1 at a predetermined size, and an appropriate mechanism such as a mechanism that controls the cutting blade through a cam or the like to perform intermittent operation, thereby cutting to a predetermined size. Can be formed. Further, the cutting may be a cutting over the entire width of the linerless printing sheet, or a partial cutting with a joining margin that can be easily separated by hand or the like.

<Regarding the substrate to be printed> As a printing method, general-purpose printing mechanisms such as a thermal transfer method using a thermal head and an ink ribbon, a sublimation type thermal transfer method, an ink-jet method using an ink-jet head and ink, and a heat-sensitive method are used. In this case, it is possible to perform printing in a good fixed state. Therefore, the substrate 11 to be printed can be appropriately formed using a sheet-like substrate made of a suitable material such as paper or a polymer.

As the linerless printing sheet 1, FIG.
As exemplified in the above, it is possible to use an appropriate material having an adhesive layer 12 without a protective cover on the back surface of a printing substrate 11 that can be printed by ink, heat, or the like.
The one or the adhesive layer 12 can take an appropriate layer form such as a single-layered product, a two-layered product, or a multi-layered product of three or more layers.

Accordingly, the substrate to be printed may be, for example, various types of paper, a film or sheet or a foamed sheet made of a polymer, a fiber, a cloth or a non-woven fabric made of the polymer, or a fiber, a cloth or a nonwoven fabric made of the polymer, depending on the object of use of the linerless printing sheet. Can be formed by an appropriate material such as a laminate using two or more of the above materials such as paper, film, foamed sheet and cloth, and a composite sheet using such a material in combination with a reinforcing base material such as a metal foil. .

Therefore, any of the known melt-type thermal transfer systems, sublimation-type thermal transfer systems, heat-sensitive systems and ink-jet systems, and other known screen-printing systems, gravure printing systems, letterpress printing systems and planographic printing systems can be used. Can be used as the substrate to be printed of the linerless printing sheet of the present invention.

The required properties of the substrate to be preferably used are that the adhesive layer provided on the back surface of the substrate to be printed has excellent adhesion support force, and when the sheet is formed into a roll, The adhesive force between the pressure-sensitive adhesive layer and the surface of the substrate to be printed is weak, so that a large force is not required for feeding the sheet, and the ink has excellent fixability. By the way, as an example, one in which the entire substrate to be printed is formed of a mixed layer of an ink-receiving polymer and a low-adhesion polymer,
Such a mixed layer is provided on a reinforcing layer or the like, a thin layer or a porous or mesh-like low-adhesion polymer layer is provided on an ink receiving layer made of paper, polymer, or the like, or on a reinforcing layer or the like. And the like provided with an ink receiving layer and a low adhesive polymer layer.

Further, the substrate to be printed may be formed of a polymer having low adhesion to a certain kind of pressure-sensitive adhesive layer and receiving a certain kind of printing ink, or a polymer layer on a reinforcing layer or the like. Those provided are also preferably used. In this case, a target label sheet can be prepared by printing as a linerless printing sheet having an adhesive layer having a low adhesive strength with the polymer layer using ink received by the polymer layer.

In the above, the ink receptive polymer used for fixing the ink with good durability includes polyolefins such as polyethylene and polypropylene, polyamides, polyesters, polyvinyl acetates, ethylene-vinyl acetate copolymers, urethane-based polymers. Polymers, acrylic polymers such as poly (meth) acrylic acid alkyl esters, polyvinyl chloride, styrene polymers, silicone polymers, natural rubber, polyisobutylene, polyisoprene, chloroprene rubber, isoprene-isobutylene rubber, nitrile butyl rubber, styrene- Butadiene rubber, styrene-butadiene-styrene rubber, styrene-isoprene-styrene rubber, styrene-ethylene-butadiene rubber, styrene-ethylene-butylene-styrene rubber, styrene- Isoprene - propylene-styrene rubber, ethylene-propylene terpolymers such as plastic-based and rubber-based polymers, such as blends thereof and the like.

Examples of the low-adhesion polymer used for the purpose of lowering the adhesion to the pressure-sensitive adhesive layer include, for example, a release coating polymer known as a pressure-sensitive adhesive sheet of silicone type, long-chain alkyl type or fluorine type, and a low molecular weight polymer. Suitable materials such as polyethylene, phosphate ester surfactants, polypropylene, and rubber polymers can be used. Preferably, a polymer for a release coat, particularly a silicone-based polymer, can be preferably used.

When the above-mentioned mixed layer is formed, the preferable mixing ratio of the ink-receiving polymer and the low-adhesion polymer is 100 parts by weight of the ink-receiving polymer, from the viewpoints of lowering the adhesive strength and preventing the lowering of the ink fixing property. Per part, 0.01 to 10 parts by weight of the low-adhesion polymer, more preferably 0.1 part by weight.
It is 1 to 8 parts by weight, particularly preferably 1 to 5 parts by weight.

On the other hand, the method in which the low-adhesion polymer is provided as a thin layer on the ink-receiving layer is achieved by reducing the adhesive force of the low-adhesion polymer to the pressure-sensitive adhesive layer by reducing the thickness of the low-adhesion polymer. The purpose is to maintain. In such a case, the thickness of the low-adhesion polymer layer is preferably 0.01 to 10 μm, more preferably 0.05 to
It is 5 μm, particularly preferably 0.1 to 2 μm.

A method of providing a porous or mesh-like layer made of a low-adhesion polymer on the ink-receiving layer is as follows.
An object of the present invention is to make it possible to fix an ink through a gap between low-adhesion polymers while achieving a reduction in adhesion between the low-adhesion polymer and an adhesive layer. For this purpose, the ratio of the porous or mesh-like low-adhesion polymer layer on the ink receiving layer is preferably 1 to 90%,
More preferably 2 to 70%, particularly preferably 5 to 50%
It is. Further, the thickness of the low-adhesion polymer layer in this case is preferably 0.01 to 100 μm from the above-mentioned point.
m, more preferably 0.05 to 50 μm, particularly preferably 0.1 to 20 μm.

The porous or mesh-like low-adhesion polymer layer can be formed by an appropriate method, and it is preferable that the gap between the low-adhesion polymers is evenly distributed as much as possible. Incidentally, the formation of a porous or mesh-like low-adhesion polymer layer is, for example, a gravure printing method or a screen printing method, a pattern forming method using a photoresist, a known porous film forming method using a dry or wet method,
It can be performed by an appropriate method such as a melt blow method, a curtain spray method, or a method of laminating a porous or mesh-like film.

On the other hand, examples of the polymer having low adhesion to the above-mentioned kind of pressure-sensitive adhesive layer and receiving a kind of printing ink include polyolefin polymers such as polyethylene and polypropylene, silicone polymers, rubber polymers, and the like. Long-chain alkyl polymers and the like can be mentioned. The molecular weight of the polymer can be appropriately determined according to the compatibility with the ink. Incidentally, in the case of a polyolefin-based polymer, it is preferably from 5 to 6,000,000 based on the viscosity average molecular weight from the viewpoint of solvent resistance and ink fixing property.

In the above, the formation of the ink-receiving layer supporting the printing substrate or the back layer or the thin layer of the polymer or the low-adhesion polymer layer such as a porous layer is performed by molding one or more polymers. It can be performed by forming a film into a film or a porous shape by an appropriate method such as a method or a coating method. In forming the film, a reinforcing agent such as a fiber, a suitable coloring agent such as a pigment such as silica or titania, alumina or zinc white, zirconia or calcium oxide, or mica, and an appropriate additive such as an antioxidant are blended. Can also. The amount of the additive is preferably 30% by weight or less from the viewpoint of printability and the like.

The linerless printing sheet only needs to have the substrate to be printed exposed on one side and the adhesive layer exposed on the other side. Therefore, a reinforcing layer or the like is provided between the substrate for printing and the adhesive layer. An appropriate layer can be interposed. The reinforcing layer is used as needed according to the use of the label sheet for the purpose of reinforcing the substrate to be printed. Therefore, as the reinforcing layer, an appropriate layer such as a polymer coating layer or film, fiber or cloth, paper or nonwoven fabric, metal foil, net, or wire can be used. The physical properties of the linerless printing sheet or label sheet can be easily controlled by selecting the reinforcing layer. In addition, measures as necessary, such as improvement of contrast with ink information to be formed, can be applied to the reinforcing layer.

The linerless printing sheet having the reinforcing layer is formed by, for example, attaching the above-described ink receiving layer of the substrate to be printed on the reinforcing layer by an appropriate method such as a heat laminating method or an extrusion coating method. The method can be carried out by an appropriate method such as a method of impregnating the layer with a solution or molten material for forming a substrate to be printed and a method of interposing a reinforcing layer in the substrate to be printed. It is preferable to use a substrate as a substrate to be printed which is excellent in flexibility, from the viewpoints of winding property and curved surface adhesion.

Incidentally, for a linerless printing sheet or the like in which a low-adhesive pressure-sensitive adhesive layer is provided on a printing substrate made of paper, the paper shows good ink receptivity, and is subjected to good printing processing by various printing methods. be able to. Also, a mixed layer of a low-adhesion polymer such as a silicone polymer and an ink-receptive polymer such as a polyester polymer, or a printing substrate comprising a thin layer of a low-adhesion polymer on the ink-receptive polymer layer, A linerless printing sheet in which a general-purpose adhesive layer such as a rubber is provided on a substrate to be printed having such a layer on a reinforcing layer such as a polypropylene synthetic paper is a sublimation-type thermal transfer system using an ink ribbon of a sublimable ink. Good print processing can be performed by the printer.

Further, a printing substrate having a porous layer made of a low-adhesion polymer such as a silicone polymer on an ink-receiving polymer layer made of a hydrophilic polymer or the like, or such a layer is placed on a reinforcing layer such as paper. A linerless printing sheet provided with a general-purpose adhesive layer such as an acrylic material on a substrate to be printed can be subjected to favorable printing processing by an inkjet printer.

An example of a printing method comprising a special combination of the above-described substrate to be printed, a pressure-sensitive adhesive layer having a low adhesion to the surface thereof, and a printing ink includes, as necessary, a silicone polymer or the like. A substrate to be printed consisting of a polyolefin-based polymer layer containing an adhesive polymer or a layer supported by a reinforcing layer such as paper, and a low-adhesion adhesive layer such as a polyester-based adhesive or an acrylic-based adhesive, A fusion-type thermal transfer system performed by combining a polyolefin-based polymer and an ink containing a colorant as a component is exemplified.

On the other hand, the substrate to be printed may be a substrate used for a heat-sensitive system in which ink information can be printed via heat of heat-sensitive paper or the like. A heat-sensitive printing substrate that can be preferably used is
A heat-sensitive coloring layer is provided on one side of a heat insulating sheet. By using the heat insulating sheet, even if the printing device accumulates heat and heats up in the continuous thermal printing process, it can prevent the heat-sensitive coloring layer from responding to the heat and preventing the color from being formed. And a sharp thermosensitive coloring pattern excellent in contrast with the above. Therefore, the heat insulating sheet enables a large amount of thermosensitive coloring patterns formed by thermal printing to be continuously formed in a clear state.

The heat insulating sheet may be a polymer sheet, depending on the purpose of use of the linerless printing sheet.
Use a suitable sheet such as a composite sheet using the polymer sheet in combination with a reinforcing base material such as fiber, cloth, non-woven fabric or metal foil, or a laminate using two or more kinds of foam sheets, paper, and polymer films. For example, a sheet made of polyethylene or the like having a crystal melting temperature of 120 ° C. or less can be used as the heat insulating sheet.

The heat-sensitive coloring layer can be appropriately formed, for example, as a layer provided with a heat-sensitive coloring property by using a leuco dye and a color developer, and can be formed as an adhesion-attaching layer of a commercially available heat-sensitive paper. Can also. The thickness of the thermosensitive coloring layer is
The thickness is generally 500 μm or less, preferably 200 μm or less, particularly preferably 5 to 100 μm, but is not limited thereto.

A release coat layer may be provided on the upper surface of the heat-sensitive coloring layer for the purpose of lowering the adhesive strength with the adhesive layer, if necessary. The release coat layer can be formed by using the above-described release agent, but from the viewpoint of prevention of heat-sensitive coloring by the attachment treatment, a silicone-based polymer containing two or more acryloyl groups or methacryloyl groups in the molecule. Release agent can be preferably used. According to this, a cured film can be formed by irradiation treatment with ionizing radiation, and thus a cured film can be formed by a low-temperature treatment, and the heat-sensitive coloring of the heat-sensitive coloring layer can be prevented.

The release coat layer is formed by applying a release agent made of the silicone polymer onto the thermosensitive coloring layer using an appropriate device such as a squeeze coater, and irradiating the coating layer with ionizing radiation. It can be performed by a method such as a treatment to form a cured film. In that case, the coating amount of the silicone-based polymer is preferably 0.05-5 g / m ^2, in particular 0.1 to 3 g / m ² is preferred. If the coating amount is less than 0.05 g / m ² , the peeling force becomes large due to insufficient film thickness, and the peeling force may not be stable. 5g /
A coating amount exceeding m ² is not practical, for example, it takes a long time for the irradiation treatment.

The thickness of the substrate to be printed may be appropriately determined according to the intended use of the linerless printing sheet. Generally, it is 1 mm or less, more preferably 1 to 500 μm, particularly preferably 5 mm or less in terms of the fixing property and strength of the ink.
The thickness is preferably 200 μm. Even when the reinforcing layer is used in combination, the ink receiving layer of the substrate to be printed is preferably 0.1 μm or more, more preferably 0.5 μm or more, and particularly preferably 1 μm or more from the viewpoints of ink fixability and strength. Thickness.

From the viewpoint of the winding property and the curved surface adhesion, etc.,
It is preferable that the substrate to be printed has excellent flexibility. Further, the substrate to be printed can be colored to a suitable color such as white by blending a suitable coloring agent such as a pigment such as silica, titania, alumina, zinc white, zirconia, calcium oxide, and mica. .

The adhesive layer provided on the back surface of the substrate to be printed is for easily adhering to the adherend in the case of a label sheet. In the present invention, the adhesive layer is formed without a protective cover such as a separator. When a wound body is adhered to the back side of the substrate to be printed, it is formed as an adhesive layer that can be fed out easily through a printing device while being easily fed out.

From the viewpoint of the easy winding property of the wound body, the adhesive strength to the surface of the substrate to be printed is 490 based on the 180 degree peel value (peeling speed 300 mm / min).
It is preferable that the pressure-sensitive adhesive layer has a thickness of 0 mN / 50 mm or less.
Further, 9.8 from the viewpoint of harmony between the automatic feeding property via a printer or the like and the adhesive force to the adherend.
It is more preferable that the adhesive layer has a thickness of 〜2940 mN / 50 mm, and it is particularly preferable that the adhesive layer has a thickness of 49 to 1470 mN / 50 mm.

For the formation of the adhesive layer, one of the appropriate adhesive substances
A kind or two or more kinds can be used, and there is no particular limitation on the kind. By the way, examples include rubber, acrylic, silicone, vinyl alkyl ether,
Examples of the adhesive include polyvinyl alcohol-based, polyvinyl pyrrolidone-based, polyacrylamide-based, cellulose-based, urethane-based, polyester-based, and polyamide-based adhesives.

The pressure-sensitive adhesive layer can also be formed of a heat-activated substance. The heat-activatable pressure-sensitive adhesive layer does not show tack before heating, and tack is generated by heating to show the properties as a pressure-sensitive adhesive layer (pressure-sensitive adhesive layer). The formation can be performed, for example, by blending a crystalline plasticizer with the above-mentioned pressure-sensitive adhesive.

As the above-mentioned crystalline plasticizer, various plasticizers which show a solid state at normal temperature can be used. In particular,
Phthalate plasticizers such as dicyclohexyl phthalate (melting point 64 ° C.), dimethyl phthalate (melting point 67 ° C.) and diphenyl phthalate (melting point 69 ° C.), dibutyl itaconate (melting point 38 ° C.) and monobutyl itaconate (melting point 4
Reactive plasticizers such as 0 ° C.) and monomethyl itaconate (melting point 67 ° C.) can be preferably used from the viewpoint of tackiness due to heating and pressure-sensitive adhesive properties.

When there is no release coat layer on the surface of the substrate to be printed, the adhesiveness to the surface of the substrate to be printed is low, the initial adhesive strength is maintained, and therefore, it is easy to feed out when a roll is formed. The pressure-sensitive adhesive layer, which is preferable from the viewpoints of properties and stability, the stability of adhesion and fixation to an adherend, includes one or more of urethane-based adhesives, polyester-based adhesives, polyamide-based adhesives, and acrylic-based adhesives. It is formed by using.

The adhesive layer is formed by providing the adhesive layer on the separator by an appropriate method such as a rolling method such as a calender roll method or a coating method such as a doctor blade method or a gravure roll coater method, and then printing the adhesive layer on a separator. It can be carried out by an appropriate method such as a method of transferring onto a predetermined surface of a substrate or a method of directly providing an adhesive layer on the back surface of a substrate to be printed according to the method.

The thickness of the pressure-sensitive adhesive layer can be appropriately determined, but is generally preferably from 1 to 500 μm from the viewpoint of adhesive strength and suitability as a printing sheet when mounted on a commercially available printer or the like. In consideration of the stable formability of the pressure-sensitive adhesive layer having a uniform thickness, the thickness is preferably 5 to 100 μm, more preferably 10 to 60 μm, and particularly preferably 15 to 40 μm.

In the example of FIG. 1, the printing mechanism 2 of the fusion type thermal transfer system using the thermal head and the fusion type ink ribbon.
However, in the present invention, for example, an ink-jet method using an ink-jet head and ink, a heat-sensitive method using various thermal writing heads such as a thermal head and a laser beam method, and a sublimation-type thermal transfer using a thermal head and a sublimation ink ribbon. A printing apparatus having an appropriate printing mechanism such as a printing method can be used. In the thermal method,
It is also possible to issue a label sheet on-the-spot by developing heat-sensitive color by an appropriate thermal printing method such as a heating pen or a heating stamp.

In the above description, when the printing mechanism is a sublimation type thermal transfer system, the ink layer is subjected to a release treatment with a release agent or the like, particularly from a release film composed of a cured film of a silicone polymer, from the viewpoint of printability. It is preferable to use an ink ribbon that has been subjected to a mold treatment. When the printing mechanism is an ink jet method, a solid-state hot-melt ink at normal temperature,
In particular, it is preferable to use a hot-melt ink containing a polymer that is tacky at room temperature as a binder component, such as the above-mentioned tacky substance, from the viewpoint of print processability and the like. When applying a roll of linerless printing sheet to a printing device,
A cassette system in which the wound body is housed in a cassette can also be used.

On the other hand, when the pressure-sensitive adhesive layer is made of a heat-activatable material, the heating for generating the tack is performed by a suitable heating means such as a thermal head, a heating roll, or a hot air spraying machine such as an infrared radiator or a dryer. Can be carried out by an appropriate method such as a method of incorporating the inside of the apparatus or a heating method outside the apparatus.

FIG. 3 shows a specific example of the above printing apparatus. This is a fusion-type thermal transfer printing apparatus (printer), according to which the linerless printing sheet 5 is fed out from its winding body 51 via a silicone rubber-coated conveying roll 62 in the printer and is continuously conveyed. In the meantime, the width direction is positioned via a guide 61 made of polyolefin at the front portion, and the leading end position of the linerless printing sheet 1 is determined via a sensor 63 to obtain the ink ribbon 6.
4, a thermal head 65, and a printing mechanism 6 comprising a silicone rubber coated platen roll 66.

In the printing mechanism 6, the ink of the ink ribbon 64 is melted by the heat generated by the thermal head 65 operating based on the print data of the plate, and the melted portion is pressed by the pressing force via the platen roll 66 for linerless printing. Is transferred to the surface of the substrate to be printed of the printing sheet 1, the ink information to be formed is fixed, the ink layer of the ink ribbon that is in close contact with the substrate to be printed via the release plate 67 is separated and printed, and the ink ribbon 64 is printed. It is wound on a collection reel 68.

Next, the quality of the printed state of the linerless printing sheet 1 after the printing is inspected through the verification mechanism 7,
When the sheet reaches the cutting mechanism 8 that is linked to the verification mechanism 7, the linerless printing sheet 1 is cut to a predetermined size in the width direction, and the label sheet 52 made of the cut pieces is formed. In the case of a defective product, a cut of the loss mark is made via the cut mechanism 8.

The ink information applied to the linerless printing sheet 1 via the printing device can be formed of any characters, figures, symbols, and the like, for example, a print pattern, a picture pattern, and a barcode pattern. Therefore, it is possible to form a label sheet on which appropriate information such as an identification label is written. In this case, the target label sheet can be formed continuously by continuously printing the ink information, and a single product or a fixed number of label sheets having a prescribed size can be formed.

Therefore, it is possible to cope with the formation of a label sheet which is occasionally issued due to issuance of a spot. The obtained label sheet can be cut into a predetermined size, and can be adhered and fixed to an appropriate target adherend via the adhesive layer.

[0074]

EXAMPLES Example 1 Low-density polyethylene containing 0.4% by weight of antioxidant and having a viscosity average molecular weight of 300,000 was weighed 80 g.
/ M ² high-quality paper extruded and laminated on one side to a thickness of 18
Forming a layer to be printed having a thickness of 25 μm, and transferring an adhesive layer having a thickness of 25 μm formed by uniformly coating an emulsion of butyl acrylate / acrylic acid copolymer on the other surface to obtain a linerless printing sheet. Was wound by a method in which an adhesive layer was adhered to the surface of a substrate to be printed to obtain a wound body.

The wound body obtained above was mounted on a fusion-type thermal transfer printer shown in FIG. 3 equipped with a commercially available fusion-type ink sheet, and the ink was thermally transferred to the surface of the substrate to be printed for printing. Then, a label sheet was obtained. As the platen roll 66 of the above-mentioned fusion type thermal transfer printer, a silicone rubber platen roll containing dimethylsiloxane (kinematic viscosity: 1000 mm ² / s) at 10 wt% was used.

Example 2 A label sheet was obtained in the same manner as in Example 1, except that a natural rubber-based pressure-sensitive adhesive (thickness: 25 μm) was used for the pressure-sensitive adhesive layer.

Example 3 A label sheet was obtained in the same manner as in Example 1, except that a silicone rubber-free platen roll containing no silicone oil was used.

Example 4 A label sheet was obtained in the same manner as in Example 2, except that a silicone rubber-free platen roll containing no silicone oil was used.

[Evaluation Test] In forming the label sheets in Examples 1 to 4, the following characteristics were examined. (1) Feeding-out transportability The feeding-out transportability of the linerless printing sheet during continuous printing processing and restarting printing after stopping for 5 hours was examined.
(2) Durability The operation of performing continuous printing for 4 hours twice a day was repeated for 30 days to examine the durability. The results are shown in the following table.

[0080] <Other Embodiments> In this embodiment, a roll (a platen roll or the like) is exemplified as the transporting means, but the present invention is not limited to this, and the present invention can be applied to other transporting means such as a belt. It is.

[Brief description of the drawings]

FIG. 1 is a partially enlarged explanatory view of a printing apparatus according to a preferred embodiment;

FIG. 2 is a cross-sectional view of a linerless printing sheet.

FIG. 3 is a side view illustrating a configuration of a printing apparatus according to another embodiment.

[Explanation of symbols]

 1,5: Linerless printing sheet 11: Printed substrate 12: Adhesive layer 13, 51: Wound body 14, 52: Print sheet (label) 2, 6: Printing mechanism 21, 66: Platen roll 22, 65 : Thermal head 23, 68: Ink ribbon 26: Ink information 3: Progressive feed mechanism 4, 8: Cut mechanism

Continuing on the front page (72) Inventor Shinji Muto 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation (72) Inventor Yoshikazu Soeda 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nitto Denko stock In-house (72) Inventor Wataru Kakimoto 1-2-1, Shimohozumi, Ibaraki-shi, Osaka Nitto Denko Corporation F-term (reference) 2C056 EA21 HA29 2C060 AA04 2C065 AA01 AD02 DC28 3F104 AA02 JC06 JD00

Claims (3)

[Claims] 1. A printing mechanism for forming ink information on a surface of a linerless printing sheet provided with an adhesive layer on the back surface of a substrate to be printed, and a printing mechanism for feeding the sheet from a roll formed by winding the sheet into a roll. And a conveying unit for conveying the sheet. The conveying unit conveys the sheet, while the ink mechanism is formed by the printing mechanism while the sheet is conveyed. A linerless printing sheet printing apparatus configured to convey the sheet in a state in which the sheet is in contact with the sheet, and at least a surface of the sheet is formed of silicone rubber containing silicone oil. 2. The silicone oil having a kinematic viscosity of 30 to 30.
100,000 mm ² / s (25 ℃) Rainaresu printing apparatus of the printing sheet according to claim 1, characterized in that a. 3. The printing of a linerless printing sheet according to claim 1, wherein a printing method in the printing mechanism is any one of a fusion type thermal transfer method, a sublimation type thermal transfer method, an ink jet method, and a thermal ink method. apparatus.