Printer and adhesive label manufacturing device

A heat-sensitive adhesive sheet is inserted into a printing device and heated by a thermal head to perform printing on a printable layer of the sheet. After printing, the heat-sensitive adhesive sheet is conveyed forward until the leading edge of the sheet abuts upon a guide roof member. While contacting the guide roof member, the leading edge of the heat-sensitive adhesive sheet is slid down and guided along the guide roof member to the nip portion of a pair of insertion rollers and is held at the nip. Once the insertion rollers have been halted, or have begun rotating slowly, the heat-sensitive adhesive sheet is conveyed further and deflected downward and assumes a concave shape. Then, the heat-sensitive adhesive sheet is cut to a predetermined length by a cutting device, and the heat-sensitive adhesive layer of the cut portion is heated and thermally activated by a thermal activation device.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a printer that employs a heat-sensitive adhesive sheet, wherein a heat-sensitive adhesive layer, which normally is not adhesive but becomes adhesive when thermally activated, is deposited on one face of a sheet base material, and produces an adhesive label that has desired characters, symbols, numbers or images recorded on the obverse face and adhesive on the reverse face, and relates to a method for producing such an adhesive label.

2. Description of the Related Art

Conventionally, as disclosed in Japanese Patent Laid-Open Publication No. Hei 11-79152, a heat-sensitive adhesive sheet having a heat-sensitive adhesive layer that becomes adhesive when heated has been put to practical use. The heat-sensitive adhesive sheet has several advantages, such as that handling the sheet before it is heated is easy and that no industrial waste is generated because release paper is not required. In order to manifest the adhesive property of the heat-sensitive adhesive layer on the heat-sensitive adhesive sheet, heating the sheet may be performed using a thermal head, one such as is commonly used for a thermal printer. Moreover, when the face of the heat-sensitive adhesive sheet opposite the thermal adhesive layer is a heat-sensitive printing enabled layer, the same type of thermal head can be used both for printing and for heating the thermal adhesive layer.

A printer for producing adhesive labels has been developed whereby desired characters, symbols, numbers or images can be printed on a printing enabled layer of a heat-sensitive adhesive sheet, the heat-sensitive adhesive sheet can be cut into predetermined lengths, and the adhesive property of the heat-sensitive adhesive layer can be manifested so that the thus produced labels can be attached to products to provide, for example, unit prices or product names (seeFIG. 5). This printer includes: a printing device101, for recording desired characters, numbers, symbols and images on a printing enabled layer100b; a cutting device102, for cutting a heat-sensitive adhesive sheet100into lengths that can serve as labels; a thermal activation device103, for thermally activating a heat-sensitive adhesive layer100ato manifest adhesion; and a conveying mechanism, for conveying the heat-sensitive adhesive sheet10through the printer. The printing device101includes: a heater (a print thermal head104) used for printing, which contacts and heats the printing enabled layer100b; and a first conveying unit (a print platen roller105), which conveys the heat-sensitive adhesive sheet100. The thermal activation device103includes: a heater (a thermal head106for thermal activation) used for thermal activation, which contacts and heats the heat-sensitive adhesive layer100a; and a second conveying unit (a pair107aof inserted rollers and a platen roller107bfor thermal activation), which conveys the heat-sensitive adhesive sheet100. Generally, the cutting device102is located between the printing device101and the thermal activation device103, and cuts into labels the heat-sensitive adhesive sheet100that has been printed.

For this printer, before the cutting device102begins to perform the cutting operation, the conveying forward of the heat-sensitive adhesive sheet100must be halted for a period of time (e.g., 0.4 seconds) while a movable blade is moved vertically. That is, while the printing device101and the second conveying device of the thermal activation device103are halted, the cutting device102cuts the heat-sensitive adhesive sheet100. Therefore, when the adhesive label to be produced is longer than the distance from the cut position of the cutting device102to the thermal head106of the thermal activation device103, the operation is halted while the heat-sensitive adhesive sheet100is held between the thermal head106and the platen roller105used for thermal activation. As a result, the heat-sensitive adhesive layer for which adhesion has now been manifested adheres to the thermal head106. Thus, when sheet feeding is resumed after the cutting has been completed and a label has been produced, the heat-sensitive adhesive sheet100is not fed smoothly, and a so-called jam occurs, one which in turn causes a conveying failure. Further, heat generated by the thermal head106is transmitted to the printing enabled layer100b, which causes color development.

An adhesive label that is thus produced and discharged from the printer is not appropriate for use because its appearance is not pleasing. Furthermore, when an adhesive label has become firmly adhered to the thermal head106of a printer, all the separate operations being performed must be halted and remedial maintenance must be performed. Thus, as described above, the efficiency with which adhesive labels are produced is deteriorated.

Therefore, in Japanese Patent Laid-Open Publication No. 2003-316265, a configuration is disclosed wherein the speeds of a printing device101and the conveying unit of a thermal activation device103are limited a heat-sensitive adhesive sheet100is deflected and assumes a convex shape between a cutting device102and the thermal activation device103; and while the operation of the conveying means is halted, the cutting device102begins the cutting of the heat-sensitive adhesive sheet100(seeFIG. 6). Specifically, a guide floor member108is located below and substantially parallel to the path along which the heat-sensitive adhesive sheet100is conveyed, and located above this path, respectively arranged at the front end and at the rear end of the guide floor member108, are a pair of induction guides109. According to this arrangement, for the portion of the heat-sensitive adhesive sheet100nearer the leading edge and along the guide floor member108the forward speed is decelerated, or the forward movement is halted, so that the portion of the heat-sensitive adhesive sheet100nearer the trailing edge is conveyed faster than the portion nearer the leading edge. In this manner, an extra long portion of the heat-sensitive adhesive sheet100is obtained on the guide floor member108, between the induction guides109, and is deflected upward, assuming a convex shape between the induction guides109. As a result, an adhesive label of a desired length can be efficiently produced.

To produce multiple adhesive labels, generally, a roll member110, around which the heat-sensitive adhesive sheet100is wound, is prepared in advance, and as the heat-sensitive adhesive sheet100is progressively unwound from the roll member110, printing, cutting and thermal activation of the heat-sensitive adhesive sheet100are performed.

According to the printer described in Japanese Patent Laid-Open Publication No. 2003-316265, a print thermal head104for a printing device101is located above the path along which the heat-sensitive adhesive sheet100is conveyed, and located below this path is a thermal head106for a thermal activation device103. Therefore, the heat-sensitive adhesive sheet100is fed with a printing enabled layer100bfacing upward and a heat-sensitive adhesive layer100afacing downward. In this case, as shown inFIG. 6, when the heat-sensitive adhesive sheet100is wound around the roll member110with the printing enabled layer100boutside and the heat-sensitive adhesive layer100ainside, the winding direction of the roll member110matches the direction in which the heat-sensitive adhesive sheet100is to be deflected between the cutting device102and the activation device103. Thus, the heat-sensitive adhesive sheet100can be smoothly deflected, and conveying and cutting of the sheet can be smoothly performed.

However, the printing enabled layer100bis the surface on which characters, symbols, numbers or images are represented when an adhesive label is completed, and on this surface, smudging is not desirable. Furthermore, there is a case wherein when the roll member110is formed the heat-sensitive adhesive sheet100is wound with the printing enabled layer100binside. In this case, as shown inFIG. 7, since the direction in which the roll member110is wound is the reverse of the direction in which the heat-sensitive adhesive sheet100is to be deflected, the heat-sensitive adhesive sheet100can not be smoothly deflected and appropriately cut to desired lengths, and smooth sheet feeding may not be performed. As a result, adhesive labels of the desired lengths can not be produced, the manufacturing accuracy is very low, and deterioration of the production yield occurs.

SUMMARY OF THE INVENTION

Therefore, the objectives of 'the present invention are to provide a printer that can smoothly deflect a heat-sensitive adhesive sheet in a direction that matches a direction in which the heat-sensitive adhesive sheet is wound around a roll member, and can easily cut the heat-sensitive adhesive sheet to predetermined lengths, and a method for manufacturing an adhesive label.

To achieve these objectives, a printer according to the present invention comprises:

a printing device for printing a printing enabled layer of a heat-sensitive sheet obtained by forming the printing enabled layer on one face of a sheet base material and forming a heat-sensitive adhesive layer on the other face;

a cutting device, located downstream of the printing device, for cutting the heat-sensitive adhesive sheet to a predetermined length;

a thermal activation device, located downstream of the cutting device, for activating the heat-sensitive adhesive layer using heat; and

a guide portion, located between the cutting device and the thermal activation device, for deflecting the heat-sensitive adhesive sheet downward in a concave shape,wherein an insertion point for the thermal activation device for the heat-sensitive adhesive sheet is located at a position lower than a delivery point for the cutting device for the heat-sensitive adhesive sheet,

wherein a guide roof member is provided for the guide portion that is located above a sheet conveying path, extending from the delivery point of the cutting device to the insertion point for the thermal activation device,

wherein, when the leading edge of the heat-sensitive adhesive sheet, which has been delivered to the cutting device from the delivery point, abuts upon the guide roof member, the heat-sensitive adhesive sheet, while in contact with the guide roof member, is slid down and guided to the entrance of the thermal activation device.

According to this arrangement, since the heat-sensitive adhesive sheet can be cut before the sheet enters the thermal activation device, a defect, such as a jam caused by the heat-sensitive adhesive sheet sticking to the thermal activation device, can be prevented, no maintenance is required to remove the jam, and the efficiency for producing adhesive labels can be considerably improved. Furthermore, according to this arrangement, the heat-sensitive adhesive sheet is deflected downward, forming a concave shape, in order for the sheet to be cut to a predetermined length. Therefore, the heat-sensitive adhesive sheet can be easily and smoothly deflected in consequence with the direction in which the sheet is wound.

The printer further comprises:

a roll member storage unit for holding a roll member around which is wound the heat-sensitive adhesive sheet to be supplied to the printing device. According to this arrangement, in addition to the configuration of the conventional printer, a choice is provided for selecting the direction in which the heat-sensitive adhesive sheet is to be deflected, in consonance with the direction in which the roll member is wound.

The printing device includes: a heater, used for printing, for contacting and heating the printing enabled layer; and a first conveying unit for conveying the heat-sensitive adhesive sheet. The thermal activation device includes: a heater, used for thermal activation, for contacting and heating the heat-sensitive adhesive layer, and a second conveying unit for conveying the heat-sensitive adhesive sheet. By controlling the second conveying unit and the first conveying unit speeds, the heat-sensitive adhesive sheet can be deflected downward to form a concave shape at the guide portion. With this arrangement, the heat-sensitive adhesive sheet can be deflected very easily, and a length to be cut can be accurately designated.

An adhesive label manufacturing method according to the invention comprises:

a printing step of a printing device heating and printing a printing enabled layer of a heat-sensitive sheet provided by forming the printing enabled layer on one face of a sheet base material and forming a heat-sensitive adhesive layer on the other face;

a cutting step, following the printing step, of a cutting device cutting the heat-sensitive adhesive sheet to a predetermined length; and

a thermal activation step, following the cutting step, of a thermal activation device heating and, thermally activating the heat-sensitive adhesive layer;

a step, preceding the cutting step, of deflecting the heat-sensitive adhesive sheet downward, so as to form a concave shape between the cutting device and the thermal activation device, until a portion, extending from the leading edge of the heat-sensitive adhesive sheet, which is delivered to the cutting device from a delivery point, to a portion facing the cutting device reaches a desired length for an adhesive label,

whereby the step of deflecting the heat-sensitive adhesive sheet downward into a concave shape includes a step ofconveying the heat-sensitive adhesive sheet so that the leading edge abuts against a guide roof member positioned above the sheet path and extending from the delivery point for the cutting device to an insertion point for the thermal activation device, the position of the insertion point being lower than the delivery point, and sliding the heat-sensitive adhesive sheet, while in contact with the guide roof member, so as to introduce the heat-sensitive adhesive sheet to the entrance of the thermal activation device.

According to this method, since the heat-sensitive adhesive sheet can be deflected downward to form a concave shape and be cut to a predetermined length, smooth deflection of the sheet, in consonance with the direction in which the heat-sensitive adhesive sheet is wound, can be easily performed.

The step of deflecting the heat-sensitive adhesive sheet downward to form a concave shape is a step of deflecting the heat-sensitive adhesive sheet by controlling the speed of the first conveying unit, part of the printing device, for conveying the heat-sensitive adhesive sheet and the speed of the second conveying unit, part of the thermal activation device, for conveying the heat-sensitive adhesive sheet.

The heat-sensitive adhesive sheet may be unwound from a roll member around which the heat-sensitive adhesive sheet is wound, with the printing enabled layer inside, and be supplied to the printing device.

According to the present invention, when a heat-sensitive adhesive sheet that is wound in a different direction from the conventional is employed, the sheet can be easily and smoothly deflected. Therefore, a desired adhesive label can be easily produced by adjusting the length of the heat-sensitive adhesive sheet, and the manufacturing efficiency can be increased.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The preferred embodiment of the present invention will now be described while referring to the accompanying drawings.

FIG. 1is a schematic cross-sectional view of the internal configuration of a printer according to the present invention for manufacturing adhesive labels based on a heat-sensitive adhesive sheet. The basic configuration of the printer using a heat-sensitive adhesive sheet will be briefly explained. This printer includes: a roll member storage unit2, for holding a roll member11formed by winding around it a heat-sensitive adhesive sheet1; a printing device3, for printing on a printing enabled layer1d(seeFIG. 2) of the heat-sensitive adhesive sheet1; a cutter device4, for cutting the heat-sensitive adhesive sheet1to a predetermined length; a thermal activation device5, for thermally activating a heat-sensitive adhesive layer1a(seeFIG. 2) of the heat-sensitive adhesive sheet1; and a guide portion6, for guiding the heat-sensitive adhesive sheet1from the cutter device4to the thermal activation device5.

The foil member11, formed by winding the heat-sensitive adhesive sheet1into a roll, is stored in the roll member storage unit2.

The printing device3includes: a thermal head7for printing (heating means for printing), which has a plurality of heat generation elements that are constituted by comparatively small resistor members arranged in the widthwise direction (direction perpendicular to the paper plane inFIG. 1) to enable dot printing; and a platen roller8for printing (first conveying unit), which is pressed against the thermal head7. The thermal head7is positioned so that it contacts the printing enabled layer1dof the heat-sensitive adhesive sheet1, which is fed from the roll member storage unit2, and the platen roller8is pressed against the thermal head7. The thermal head7has the same structure as the print head of a well known thermal printer, for which a glass ceramics protective film is deposited on the surfaces of a plurality of heat-generating resistor members formed on a ceramic substrate.

The cutter device4cuts, to a predetermined length, the heat-sensitive adhesive sheet1printed by the printing device3and forms the sheet1into label forms. The cutter device4includes: a movable blade4apropelled by a drive source (not shown), such as an electric motor, and a fixed blade4blocated opposite the movable blade4a.

In the guide portion6, a guide roof member6ais arranged above the path along which the heat-sensitive adhesive sheet1is conveyed from the cutter device4to the thermal activation device5. As will be described later, the guide roof member6ais not only used to smoothly introduce the heat-sensitive adhesive sheet1to the thermal activation device5, but also to hold the heat-sensitive adhesive sheet1between the delivery point or exit for the cutter device4and the insertion point or entrance for the thermal activation device5, while the sheet1is deflected downward and assumes a concave shape (seeFIGS. 4A to 4D), so that the heat-sensitive adhesive sheet1can be cut to a desired length by the cutting device4.

The thermal activation device5includes: a thermal head9, used for thermal activation, that has a plurality of heat generation elements (not shown); a platen roller10, for thermal activation; a pair of insertion rollers13; and a discharge roller12. The thermal head9is positioned so that it contacts the heat-sensitive adhesive layer1aof the heat-sensitive adhesive sheet1, and the platen roller10is pressed against the thermal head9. In this embodiment, the pair of insertion rollers13is specifically called a second conveying unit.

The thermal head9has the same structure as the thermal head7of the above described printing device3, i.e., the same structure as the print head of a well known thermal printer, for which a glass ceramics protective film is deposited on the surfaces of multiple heat-generating resistor members mounted on a ceramic substrate. Since the same structure is employed for the thermal head7for printing and the thermal head9for thermal activation, the parts can be used in common and manufacturing costs can be reduced. Furthermore, since to generate heat multiple small heat generation elements (heat-generating resistor members) are used to constitute the thermal head, an advantage of this structure is that a uniform temperature can be easily distributed across a wide range, compared with a structure wherein a single (or an extremely few) large heat generation element is employed to generate heat. It should be noted 'that unlike the heat generation elements of the thermal head7, the heat generation elements of the thermal head9need not be divided into dot units, and sequential resistor elements may be employed.

The insertion point for the thermal activation device1, i.e., the nip portion for the paired insertion rollers13, is lower than the delivery point for the cutter device4, i.e., the space between the movable blade4aand the fixed blade4b. Thus, a flat plate is used to form the guide roof member6a, which is positioned above the path along which the heat-sensitive adhesive sheet1is conveyed and inclines obliquely downward from the delivery point for the cutter device4to the insertion point for the thermal activation device5.

As the heat-sensitive adhesive sheet1used for this embodiment, as shown inFIG. 2for example, an insulating layer1cand a heat-sensitive color developing layer (a printable or printing enabled layer)1dare formed on the obverse side of a sheet base material1b, and the heat-sensitive adhesive layer1ais obtained by coating, drying and solidifying a heat-sensitive adhesive agent that contains as the main element a thermoplastic resin or a solid plastic resin, for example. It should be noted that the structure of the heat-sensitive adhesive sheet1is not limited to the one shown, and that various other structures can be employed so long as the heat-sensitive adhesive layer1ais included. As an example, a heat-sensitive adhesive sheet1may also be employed for which an insulating layer1cis not included or for which a protective layer or a color printed layer (a layer on which printing is performed in advance) is deposited on the surface of the printing enabled layer1d, or on which a thermal coat layer is deposited (neither structure is shown). In this embodiment, the roll member11is formed by winding the heat-sensitive adhesive sheet1around it with the printing enabled layer1don the inside and the heat-sensitive adhesive layer1aon the outside. One of the reasons this is done is to prevent dirt from accumulating on the printing enabled layer1don which label information such as desired characters, symbols, numbers and images are to be printed.

The platen roller8used for printing, the paired insertion rollers13, the platen roller10used for thermal activation and the discharge roller12constitute a conveying mechanism for conveying the heat-sensitive adhesive sheet1through the printer.

Furthermore, although not shown, the printer also includes a controller for driving the conveying mechanism, the thermal head7for printing and the thermal head9for thermal activation, for example, and for controlling the operations of these sections.

While referring to the flowchart inFIG. 3, an explanation will be given for a method that uses the thus arranged printer to produce desired adhesive labels from the heat-sensitive adhesive sheet1.

First, the heat-sensitive adhesive sheet1is pulled forward, unwinding it from the roll member11in the roll member storage unit2, and is inserted between the thermal head7and the platen roller8of the printing device3. A print signal is supplied by the controller to the thermal head7, the heat generation elements of the thermal head7are selectively driven at an appropriate timing to generate heat, and printing is performed on the printing enabled layer1dof the heat-sensitive adhesive sheet1. Synchronized with the driving of the 'thermal head7, the platen roller8is rotated to convey the heat-sensitive adhesive sheet1in a direction perpendicular to the direction in which the heat generation elements of the thermal head7are arranged, e.g., the direction perpendicular to the array of heat generation elements. Specifically, alternately performed are the printing of one line by the thermal head7and the conveying of the heat-sensitive adhesive sheet1a predetermined distance (the equivalent of one line) by the platen roller8are so that desired characters, numbers, symbols or images are printed on the heat-sensitive adhesive sheet1(step S1).

The thus printed heat-sensitive adhesive sheet1is passed between the-movable blade4aand the fixed blade4bof the cutter device4, and reaches the guide roof member6a. At the guide roof member6a, the heat-sensitive adhesive sheet1is appropriately deflected, so that the length between the leading edge of the heat-sensitive adhesive sheet1to the portion positioned between the movable blade4aand the fixed blade4bof the cutter device4is designated,(step S2). The step of deflecting the heat-sensitive adhesive sheet1will be described in detail while referring toFIGS. 4A to 4D.

First, the leading edge of the heat-sensitive adhesive sheet1, which has been forwarded by the platen roller8, is passed between the movable blade4aand the fixed blade4bof the cutter device4, and as shown inFIG. 4A, abuts upon the guide roof member6a(step S2a). As the heat-sensitive adhesive sheet1is forwarded further, as shown inFIG. 4B, it slides down along the guide roof member6a(step S2b). Then, as shown inFIG. 4C, the leading edge of the heat-sensitive adhesive sheet1is guided along the guide roof member6ato the nip portion of the pair of insertion rollers13(step S2c). During this process, the leading edge of the heat-sensitive adhesive sheet1continues to remain in contact with the guide roof member6a. By the time whereat the leading edge of the heat-sensitive adhesive sheet1has been guided to the nip portion, the insertion rollers13have been rotated, and when the leading edge is gripped at the nip portion and the heat-sensitive adhesive sheet1is appropriately held, the insertion rollers13are either halted, or rotated at a conveying speed slower than that of the platen roller8. Therefore, the portion of the heat-sensitive adhesive sheet1present in the guide portion6is gradually increased so that it exceeds the linear length of the path, extending from the cutter device4to the thermal activation device5, along which the heat-sensitive adhesive sheet1is conveyed, i.e., extra length is provided for the relevant portion of the heat-sensitive adhesive sheet1. As shown inFIG. 4D, the extra length portion is deflected downward so that it bows and assumes a concave shape (step S2d), and the extra length portion accumulates in the space between the delivery point (exit) of the cutter device4and the insertion point (entrance) of the thermal activation device5. At this time, the top of the sheet conveying path is covered with the guide roof member6a, and since the guide roof member6ais inclined obliquely forward, the heat-sensitive adhesive sheet1is deflected not upward but downward to assume the concave shape.

Thereafter, the speeds and the operating periods of the platen roller8and the insertion rollers13are monitored by using a sensor (not shown). When the length from the leading edge of the deflected heat-sensitive adhesive sheet1to the portion located between the movable blade4aand the fixed blade4bof the cutter device4corresponds to the length of an adhesive label to be produced, the platen roller8is temporarily halted and the heat-sensitive adhesive sheet1is cut by driving the movable blade4a.(step S3). In this manner, a label having a predetermined length can be formed from the heat-sensitive adhesive sheet1.

Following this, the insertion rollers13and the platen roller10for thermal activation are rotated, and feed to the thermal activation device5, the label, on which required printing has been performed in the above described manner, having the predetermined length that has been formed from the heat-sensitive adhesive sheet1. In the thermal activation device5, in the state wherein the label of the heat-sensitive adhesive sheet1is sandwiched between the thermal head9and the platen roller10, the controller drives the thermal head9so as to thermally activate the heat-sensitive adhesive layer la that contacts the thermal head9. At the same time, the platen roller10is rotated to feed the label of the heat-sensitive adhesive sheet1, and while the heat-sensitive adhesive sheet1is pressed against the thermal head9by the platen roller10, the thermal head9is activated to generate heat, so as to thermally activate the portion of the heat-sensitive adhesive layer la that contacts the thermal head9(step S4). At the same time, as the platen roller10is rotated, the label formed from the heat-sensitive adhesive sheet1is conveyed, while along its entire surface the heat-sensitive adhesive layer la is brought into contact with the thermal head9. Therefore, adhesion is manifested along the entire heat-sensitive adhesive layer la on one side of the label formed from the heat-sensitive adhesive sheet1.

As a result, the processing is completed for the production, from the heat-sensitive adhesive sheet1, of an adhesive label having a predetermined length, along one side of which desired printing has been performed and along the other side of which adhesion has been manifested, and the adhesive label is discharged, outside the printer, by the discharge roller12(step S5).

When the pair of insertion rollers13are to be halted at the time whereat the leading edge of the heat-sensitive adhesive sheet1has been guided to the nip portion of the insertion rollers13, the insertion rollers13must be halted before the leading edge of the heat-sensitive adhesive sheet1contacts the thermal head9, e.g., immediately after the leading edge is gripped and held at the nip portion. This is because the contact portion of the heat-sensitive adhesive sheet1will be heated excessively if contacting the thermal head9when the platen roller10and/or the insertion rollers13are halted.

Further, when the heat-sensitive adhesive sheet1is to be deflected by slowly rotating the insertion rollers13, for the same reasons as described above, the insertion rollers13and the platen roller10must be continuously rotated without stopping, at least after the heat-sensitive adhesive sheet1contacts the thermal head9. Since the heat-sensitive adhesive sheet1is deflected at the guide portion6, during the cutting process performed by the cutter device4, the thermal head9and the platen roller10can be continuously operated, and the thermal activation process can be performed in parallel.

As described above, according to this embodiment, at the guide portion6between the cutter device4and the thermal activation device5, the heat-sensitive adhesive sheet1is deflected downward and assumes a concave shape, so that the length of the heat-sensitive adhesive sheet1can be adjusted and an adhesive label having a desired length can be easily produced. Further, even when, as in the configuration inFIG. 1, the roll member11is formed by winding the heat-sensitive adhesive sheet1with the printing enabled layer1dinside and the heat-sensitive adhesive layer1aoutside, is employed, since the winding direction of the roll member11matches the direction in which the heat-sensitive adhesive sheet1is deflected, the heat-sensitive adhesive sheet1can be smoothly conveyed, and the sheet1can be accurately cut to a predetermined length.

According to the conventional configuration disclosed in Japanese Patent Laid-Open Publication No. 2003-316265, as shown inFIG. 6, it is very easy for the heat-sensitive adhesive sheet to be deflected upward, above the guide floor member. However, merely by reversing the structure of the guide portion, the heat-sensitive adhesive sheet can not be deflected downward. This is because once the leading edge of the heat-sensitive adhesive sheet is deflected downward, since the leading edge of the heat-sensitive adhesive sheet that is being conveyed forward is suspended by gravity, it can not be raised to the horizontal position and returned to the conveying path. Therefore, the extra length portion of the heat-sensitive adhesive sheet is simply suspended by gravity and separated from the conveying path. As described above, conventionally, even when downward deflection of a sheet is demanded, no structure that enables this has been proposed.

On the other hand, according to this invention, as shown inFIGS. 4A to 4D, first, the insertion point of the thermal activation device5is located lower than the delivery point of the cutter device4, and second, the guide roof member6a, which inclines obliquely downward in the forward direction, is provided above the conveying path, between the delivery point and the insertion point. With this arrangement, the deflection downward of the heat-sensitive adhesive sheet1is enabled by exploiting the resilience of the heat-sensitive adhesive sheet1. That is, when the leading edge of the heat-sensitive adhesive sheet1abuts upon the guide roof member6a, as shown inFIG. 4A, the resilience of the heat-sensitive adhesive sheet1prevents the leading edge from separating from the guide roof member6aas it slides down, as shown inFIG. 4B, and is guided to the nip portion between the pair of insertion rollers13, as shown inFIG. 4C. Thereafter, as shown inFIG. 4D, when the leading edge has been gripped and is held at the nip portion of the pair of insertion rollers13, which are not rotated or are rotated slowly, and the heat-sensitive adhesive sheet1is conveyed further, the heat-sensitive adhesive sheet1is deflected downward and assumes a concave shape. With this arrangement, the heat-sensitive adhesive sheet1is prevented from being freely suspended by gravity, and can be deflected downward smoothly.

In order to obtain the smooth deflection shown inFIGS. 4A to 4D, the angle and the length of the guide roof member6amust be appropriately designated, while taking into account the resilience of the heat-sensitive adhesive sheet l, determined in accordance with the material and the thickness of the heat-sensitive adhesive sheet1, so that the leading edge will not be folded when it abuts upon the guide roof member6a, and will not be separated from the guide roof member6aand freely suspended by gravity.