Patent ID: 12246544

DETAILED DESCRIPTION

Next, embodiments of the present invention will be described while referring to the accompanying drawings. The referenced drawings are used to describe the technical features made possible with the present invention. The configurations of the apparatuses described below are merely examples, and the present invention is not intended to be limited to these configurations.

First, a printing tape cassette30and a printing device1in which the printing tape cassette30is mounted will be described with reference toFIGS.1through5according to a first embodiment of the invention. In the following description of the embodiment, the lower-left side, upper-right side, lower-right side, and upper-left side of the printing device1inFIG.1are respectively defined as the front side, rear side, right side, and left side of the printing device1. The lower-right side, upper-left side, upper-right side, and lower-left side of the printing tape cassette30inFIG.2are respectively defined as the front side, rear side, right side, and left side of the printing tape cassette30. A group of gears shown inFIG.2that include gears91,93,94,97,98, and101is actually covered and hidden by the bottom surface of a cavity8a. However, the bottom surface of the cavity8ais not shown inFIG.2for the purpose of describing this group of gears.FIG.2also schematically depicts side walls that form a periphery around a cassette housing section8, but this is merely a schematic diagram and the side walls are drawn thicker than the thickness of the actual side walls. Further, to facilitate understanding, the printing tape cassette30mounted in the cassette housing section8inFIG.3is depicted without an upper case31a.

Structure of a Printing Device1According to a First Embodiment

The structure of a printing device1in which a printing tape cassette30is mounted will be described with reference toFIG.1. As shown inFIG.1, the printing device1is a general-purpose tape printing device in which various types of printing tape cassettes can be commonly used, including a thermal type, a receptor type, and a laminated type. The printing device1is provided with a main unit cover2, a keyboard3, a display5, and a cassette cover6. The main unit cover2has a rectangular parallelepiped shape in a plan view. The keyboard3is arranged on the front side of the main unit cover2. The keyboard3includes character keys for alphabetic and numeric characters and symbols, and various function keys. The display5is provided on the rear side of the keyboard3. The display5can display inputted alphanumeric characters and symbols. The cassette cover6is provided on the rear side of the display5. The cassette cover6is opened and closed when replacing the printing tape cassette30. While not shown in the drawings, a discharge slit is provided toward the rear on the left side of the main unit cover2. Tape that has been printed is discharged from the main unit cover2through this discharge slit. A discharge window is also formed on the left side surface of the cassette cover6. The discharge slit is exposed on the outside of the main unit cover2through the discharge window when the cassette cover6is in a closed state.

The internal structure of the main unit cover2under the cassette cover6will be described next with reference toFIG.2. As shown inFIG.2, a cassette housing section8is provided inside the main unit cover2in a region corresponding to the cassette cover6. Thus, when the cassette cover6is open, the printing tape cassette30can be freely inserted into and removed from the cassette housing section8. The cassette housing section8includes a cavity8a, and a cassette support part8b. The cavity8ais formed as a depression that substantially corresponds to the shape of a bottom surface30bof a cassette case31described later and has a flat bottom surface. The cassette support part8bis a flat surface that extends horizontally from the outer edges of the cavity8a. The cassette support part8bhas a rectangular shape elongated in the left-right direction in a plan view and corresponds substantially to the shape of the printing tape cassette30in a plan view. In a plan view, the rear edge of the cavity8ahas two arcs formed adjacent to each other in the left-right direction.

As shown inFIG.2, two positioning pins102and103are provided at two locations on the cassette support part8b. More specifically, the positioning pin102is provided on the left side of the cavity8aand the positioning pin103is provided on the right side of the cavity8a. The positioning pins102and103are disposed in positions respectively corresponding to pin holes62and63described later when the printing tape cassette30is mounted in the cassette housing section8. The pin holes62and63are two recessed parts formed in the bottom surface of the printing tape cassette30. When the printing tape cassette30is mounted in the cassette housing section8, the positioning pins102and103are respectively inserted into the pin holes62and63, thereby supporting the printing tape cassette30from below at left and right positions on the peripheral portion of the printing tape cassette30.

The cassette housing section8is also provided with a conveying mechanism that conveys tape drawn out from the printing tape cassette30, a printing mechanism that prints characters and the like on the surface of the tape, and the like. As shown inFIG.2, a head holder74is fixedly disposed on the front side of the cassette housing section8, and a thermal head10provided with heating elements (not shown) is mounted in the head holder74.

A tape feed motor23is arranged on the outer side of the cassette housing section8(the upper-right side inFIG.2). The tape feed motor23is configured of a stepping motor. A drive gear91is fixed to the lower end of a drive shaft in the tape feed motor23. The drive gear91is meshed with a gear93through an opening penetrating the right wall of the cassette housing section8, and the gear93is meshed with a gear94. A ribbon take-up shaft95is disposed in an upright state on the top surface of the gear94. The ribbon take-up shaft95drives a ribbon take-up spool44described later to rotate. A gear97is also meshed with the gear94, a gear98is meshed with the gear97, and a gear101is meshed with the gear98. A tape drive shaft100is disposed in an upright state on the top surface of the gear101. The tape drive shaft100drives a tape drive roller46described later to rotate.

When the tape feed motor23is driven to rotate in the counterclockwise direction while the printing tape cassette30is mounted in the cassette housing section8, the ribbon take-up shaft95is also driven to rotate in the counterclockwise direction via the drive gear91, gear93, and gear94. The rotation of the ribbon take-up shaft95drives the ribbon take-up spool44in the printing tape cassette30to rotate. The ribbon take-up spool44is mounted over the ribbon take-up shaft95. The rotation of the gear94is also transmitted to the tape drive shaft100via the gear97, gear98, and gear101, thereby driving the tape drive shaft100to rotate in the clockwise direction. The rotation of the tape drive shaft100drives the tape drive roller46in the printing tape cassette30to rotate. The tape drive roller46is mounted over the tape drive shaft100.

As shown inFIG.3, an arm-like platen holder12is pivotably supported about a support shaft12aprovided on the front side of the head holder74. A platen roller15and a movable feed roller14are both rotatably supported on the distal end of the platen holder12. The platen roller15is disposed so as to be capable of contacting and separating from the thermal head10when the platen holder12pivots, while the movable feed roller14is disposed so as to be capable of contacting and separating from the tape drive roller46that is mounted over the tape drive shaft100.

A release lever (not shown) is coupled with the platen holder12. The release lever moves in the left-right direction in association with the opening and closing of the cassette cover6. Specifically, when the cassette cover6is opened, the release lever moves rightward, and the platen holder12moves toward a standby position (the position depicted with dashed lines inFIG.3). When moving toward the standby position, the platen holder12separates from the cassette housing section8, allowing the printing tape cassette30to be inserted into or removed from the cassette housing section8. A coil spring (not shown) constantly urges the platen holder12elastically toward the standby position (counterclockwise in a plan view).

When the cassette cover6is closed, on the other hand, the release lever moves leftward, and the platen holder12moves toward a printing position depicted with solid lines inFIG.3. When moving toward the printing position, the platen holder12moves in a direction approaching the cassette housing section8. When a thermal-type printing tape cassette30possessing a first tape59and a second tape58is mounted in the cassette housing section8, as illustrated inFIG.3, the platen roller15presses the first tape59against the thermal head10while the movable feed roller14presses the first tape59and second tape58against the tape drive roller46.

As shown inFIG.3, the printed first tape59and the second tape58become a printing tape50after joining at the nip point between the movable feed roller14and tape drive roller46. The printing tape50exits the printing tape cassette30via a tape discharge part49. A conveying path for conveying the printing tape50is provided from the tape discharge part49to the discharge slit (not shown) in the printing device1. A cutting mechanism17is disposed on the conveying path for cutting the printing tape50at a prescribed position. The cutting mechanism17is configured of a fixed blade18, and a movable blade19that opposes the fixed blade18and is supported to be capable of moving in the front-rear direction (vertical direction inFIG.3). A cutter motor (not shown) is provided for moving the movable blade19in the front-rear direction.

2. Structure of the Printing Tape Cassette30According to the First Embodiment

Next, the structure of the printing tape cassette30according to the first embodiment will be described with reference toFIGS.2through4. As shown inFIG.3, the printing tape cassette30has a cassette case31, the first tape59, and the second tape58. As shown inFIG.2, overall, the cassette case31is a substantially rectangular parallelepiped (box-shaped) housing with corners that are rounded in a plan view. The cassette case31is configured of a lower case31band an upper case31a. The lower case31bincludes a bottom surface30bof the cassette case31. The upper case31aincludes a top surface30aof the cassette case31and is fixed to the top of the lower case31b. When the upper case31aand lower case31bare fixed together, a side surface30cof a prescribed height is formed along the outer edges of the top surface30aand bottom surface30b. In other words, the cassette case31is a box-like casing that includes the top surface30aand bottom surface30bconstituting a pair of rectangular-shaped planar surfaces oppositely arranged in the vertical direction, and the side surface30cformed at a prescribed height along the outer edges of the top surface30aand bottom surface30b(in this example, four sides surfaces including the front surface, rear surface, left side surface, and right side surface). The combination of the top surface30a, bottom surface30b, and the side surface30cdefines an internal space. The first tape59and the second tape58are accommodated in the internal space and wound in a roll. In the cassette case31, the side surface30cneed not enclose the entire peripheries of the top surface30aand bottom surface30b. For example, an opening may be provided in a portion of the side surface30c(the rear surface, for example) that exposes the interior of the cassette case31, and a boss connecting the top surface30ato the bottom surface30bmay be provided in a position confronting this opening. In the first embodiment, the vertical dimension of the cassette case31(i.e., the direction in which the top surface30aand bottom surface30boppose each other) substantially corresponds to the direction in which the printing tape cassette30is inserted into and removed from the cassette housing section8.

The front side of the cassette case31is provided with an arm part34, a head insertion section39, guide parts36, and a tape discharge part49. The arm part34extends diagonally leftward and forward from the right front portion of the printing tape cassette30. The extended direction of the arm part34is substantially aligned with the longitudinal direction of the cassette case31(left-right direction). An opening34athat is elongated vertically is formed in the distal end (left end) of the arm part34. When the cassette case31is assembled by joining the upper case31aand lower case31btogether, a conveying path is formed inside the arm part34for guiding conveyance of the first tape59. As shown inFIG.3, after the first tape59is guided along this conveying path, the first tape59is discharged through the opening34ainto the head insertion section39(and more specifically an opening77described later). Thus, the opening34ais provided in the side surface30cand constitutes the portion in the cassette case31through which the first tape59guided along the prescribed conveying path passes from the inside to the outside of the cassette case31.

The head insertion section39is a space surrounded by a rear surface37of the arm part34, and a peripheral surface of the cassette case31formed continuously with the rear surface37of the arm part34, and has a general rectangular shape in a plan view. The head insertion section39penetrates the printing tape cassette30vertically. The head insertion section39is provided in a forwardly biased position in the cassette case31(i.e., in a position biased toward the side opposite the second tape58and first tape59). As shown inFIG.4, the head insertion section39also communicates with the outside of the printing tape cassette30at the front side thereof through an opening77formed in the front surface of the printing tape cassette30. The head holder74that supports the thermal head10of the printing device1is inserted into the head insertion section39. The thermal head10prints on the first tape59discharged through the opening34aof the arm part34in the opening77where the first tape59is exposed to the outside of the cassette case31.

The guide parts36are provided on the side surface30cupstream of the tape drive roller46. After the first tape59has passed out of the cassette case31through the opening34aand has been printed by the thermal head10in the opening77, the guide parts36guide the first tape59back inside the cassette case31. The guide parts36in this example are a pair of bar-shaped members extending vertically. The guide parts36guide the printed first tape59from the downstream side of the thermal head10toward the tape discharge part49while restricting movement of the first tape59vertically (in the direction along the tape width). Hence, the guide parts36ensure that the printed first tape59is properly bonded to the second tape58with no positional displacement therebetween.

The tape discharge part49is a plate-shaped member spanning between the top surface30aand bottom surface30bof the cassette case31. The tape discharge part49is slightly separated in the forward direction from the front end on the left side surface of the cassette case31. The tape discharge part49guides the printing tape50conveyed over the guide parts36and tape drive roller46into a passage formed between the front end on the left side surface of the lower case31band the side surface of the cavity8a, and discharges the printing tape50through a tape discharge opening (not shown) at the downstream end of the passage.

As shown inFIG.4, pin holes62and63are provided in the bottom surface30bto correspond to the positioning pins102and103of the printing device1described above. Specifically, a recessed part provided in the left-front portion (the lower-right corner inFIG.4) of the cassette case31, constitutes the pin hole62in which the positioning pin102is inserted. A recessed part provided near the center region on the right edge of the cassette case31constitutes the pin hole63in which the positioning pin103is inserted.

Support holes65a,66a, and67a(seeFIG.2) are formed in the upper case31a, and support holes65b,66b, and67b(seeFIG.4) are formed in the lower case31bfor rotatably supporting a first tape spool40and a second tape spool41described later, as well as the ribbon take-up spool44.

As shown inFIG.3, the first tape59is a long strip of tape wound in a roll about the second tape spool41. As shown inFIG.5, the first tape59is configured of a first protective layer591, a heat-sensitive layer592, and a second protective layer593. The first protective layer591is provided on the heat-sensitive layer592. The first protective layer591transmits light. The first protective layer591should be capable of transmitting a sufficient amount of light for observing color development in the heat-sensitive layer592. For example, the first protective layer591may be formed of a resin, such as polyethylene (PE), polypropylene (PP), ethylene vinyl acetate (EVA) copolymer, ethylene methacrylic acid (EMAA) copolymer, polybutene (PB), polybutadiene (BDR), polymethylpentene (PMP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyimide (PI), polyetherimide (PEI), polyetherketone (PEK), polyether ether ketone (PEEK), nylon (NY), polyamide (PA), polycarbonate (PC), polystyrene (PS), expanded polystyrene (FS/EPS, also called foamed “polystyrene”), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), saponified ethylene vinyl alcohol (EVOH), polyvinyl alcohol (PVA), plain transparent (PT) cellophane, moisture-proof sealable transparent (MST) cellophane, polyacrylonitrile (PAN), vinylon (VL), polyurethane (PU), and triacetyl cellulose (TAC). For example, the first protective layer591may be formed of a metal foil (aluminum foil or copper foil), a vacuum metalized (VM) film, or the like, or may be configured of one of various types of paper, including translucent paper, washi (traditional Japanese paper), wood-free paper, dust-free paper, glassine paper, clay-coated paper, resin-coated paper, laminated paper (polyethylene-laminated paper, polypropylene-laminated paper, etc.), synthetic paper, kraft paper, and the like. The first protective layer591may also be formed of a nonwoven cloth or a glass cloth, for example.

The first protective layer591is provided to protect the heat-sensitive layer592from oil, dirt, and the like and to enhance resistance to various matter (resistance to plasticizers, water, oil, and chemicals). The first protective layer591is formed of a water-soluble resin (polyvinyl alcohol, etc.), a resin emulsion, and the like. The heat-sensitive layer592produces color at temperatures within a prescribed range. The heat-sensitive layer592includes leuco dye, developer, auxiliary agents (fillers, binders, lubricants, antioxidants, water-resistant additives, film-forming assistants, pigments, stabilizers, dispersants, antifoaming agents, etc.), and the like.

The second protective layer593is provided on the side of the heat-sensitive layer592opposite the first protective layer591. The second protective layer593includes at least one resin from among fluorine-based resins, silicone-based resins, olefin-based resins, polyester-based resins, epoxy/polyester-based resins, and silicon-based resins. Resins included in the second protective layer593are preferably polyvinyl fluoride resins (fluorides), polyvinylidene fluoride resins (difluorides), polychlorotrifluoroethylene resins (trifluorides), and polytetrafluoroethylene resins (tetrafluorides), and most preferably polytetrafluoroethylene resins. The second protective layer593is formed of material that transfers heat to the heat-sensitive layer592. As shown inFIG.3, the second tape spool41about which the first tape59is wound is disposed so as to be rotatable via the support hole66a(seeFIG.2) and the support hole66b(seeFIG.4). The second protective layer593in the section of the first tape59positioned between the opening34aand guide parts36confronts the thermal head10provided in the cassette housing section8of the printing device1.

As shown inFIG.3, the second tape58is wound in a roll about the first tape spool40and is accommodated in the interior space of the cassette case31. As shown inFIG.5, the second tape58is provided with a first adhesive layer581, and a base material582. The first adhesive layer581includes at least one adhesive from among an emulsion-type adhesive containing an acrylic polymer and a rubber-based adhesive and compounded with a tackifying resin, silicone based adhesive, and rubber-based adhesive. The first adhesive layer581is bonded to the second protective layer593of the first tape59.

The base material582is bonded to the surface of the first adhesive layer581on the side opposite the surface bonded to the second protective layer593. The base material582in this example is a release paper. The base material582may be configured of paper, film, or synthetic paper. In the preferred embodiment, the surface of the base material582on the first adhesive layer581side is subjected to a non-silicone-based release treatment, and the surface of the base material582on the opposite side from the first adhesive layer581is also subjected to a non-silicone-based release treatment. In other words, one surface of the base material582on the first adhesive layer581side is subjected to a non-silicone-based release treatment. Another surface opposite the surface of the base material582is subjected to non-silicone release treatment.

The non-silicone-based release agent used in this release treatment is a pendant-type polymer of a long-chain fatty acid produced by reacting an aliphatic isocyanate with polyvinyl alcohol, or the like. A non-silicone-based release agent can be used to form a release coating simply by applying a liquid composition formed by dissolving the release agent in solvent to a supporting medium and drying the liquid composition, for example, without needing to use a special catalyst or to perform heat treatment or other processes when forming the release coating. As shown inFIG.3, the first tape spool40is disposed so as to be rotatable via the support hole65a(seeFIG.2) and the support hole65b(seeFIG.4). The second tape58is wound about the first tape spool40such that the base material582faces outward and is arranged and conveyed in a manner that brings the first adhesive layer581against the second protective layer593of the first tape59. In other words, the second tape58is wound in a roll about the first tape spool40with the first adhesive layer581facing inward.

3. Overview of the Printing Process on the Printing Device1

When the printing device1performs printing, the tape drive roller46driven to rotate via the tape drive shaft100pulls the first tape59from the second tape spool41in cooperation with the movable feed roller14. The first tape59drawn off the second tape spool41is redirected leftward at the bottom-right corner of the cassette case31in a plan view (i.e. at the right-front corner of the cassette case31) and conveyed along the conveying path in the arm part34. The first tape59is supplied through the opening34aof the arm part34into the opening77and is conveyed between the thermal head10and platen roller15. The first tape59receives heat from the thermal head10on the second protective layer593side while between the opening34aand the guide parts36. This heat produces printed characters, graphics, symbols, and the like in the heat-sensitive layer592. The tape drive roller46and movable feed roller14work in concert to convey the printed first tape59onto the prescribed conveying path while the first tape59is guided by the guide parts36so that the first adhesive layer581of the second tape58adheres to the second protective layer593of the first tape59(seeFIG.5(A)). The first tape59having the second tape58affixed thereto becomes the printing tape50. This printing tape50is conveyed toward the tape discharge part49and cut by the cutting mechanism17.

4. First Variation of the Printing Tape Cassette30According to the First Embodiment

In the printing tape cassette30according to the first embodiment, the first tape59may be arranged such that the first protective layer591opposes the thermal head10provided in the cassette housing section8of the printing device1while passing between the opening34aand the guide parts36, as illustrated inFIG.5(B). In this case, the first protective layer591is preferably formed of a material that conveys heat to the heat-sensitive layer592.

5. Second Variation of the Printing Tape Cassette30and the Printing Tape50According to the First Embodiment

The second tape used to form the printing tape50may be configured to include a double-sided tape base material571, as in a second tape258illustrated inFIG.5(C). In this case, the second tape258may include a second adhesive layer572affixed to the side of the double-sided tape base material571opposite the first adhesive layer581, and a release paper573affixed to the second adhesive layer572.

In the first embodiment and the first variation, the cassette case31, top surface30a, bottom surface30b, and side surface30care respective examples of the cassette case, first surface, second surface, and third surface in the present invention. The first tape59, heat-sensitive layer592, first protective layer591, and second protective layer593are respective examples of the first tape, heat-sensitive layer, first protective layer, and second protective layer in the invention. The second tape58, first adhesive layer581, and base material582are respective examples of the second tape, the first adhesive layer, and the base material in the invention. In the second variation, the double-sided tape base material571is an example of the base material in the invention.

6. Tests for Evaluation

The printing characteristics of the printing tape50according to the first embodiment were evaluated by testing a tape whose second protective layer includes polyvinyl alcohol as a comparative example, and a tape whose second protective layer includes fluorine-based resin as an example of the preferred embodiment. The same heat-sensitive layer, first adhesive layer, and second adhesive layer were used in both the comparative example and the example of the embodiment. Specifically, as indicated inFIG.10, the heat-sensitive layer used in the experiments was a common heat-sensitive layer that included leuco dye, developer, auxiliary agents (fillers, binders, lubricants, antioxidants, water-resistant additives, film-forming assistants, pigments, stabilizers, dispersants, antifoaming agents, etc.), and the like. The first protective layer was formed of PET at a thickness of 25 μm. The first adhesive layer was formed with an acrylic-based adhesive (solvent). The second protective layer in the comparative example was formed of polyvinyl alcohol at a thickness of approximately 1 μm. The second protective layer in the example of the embodiment was formed of polytetrafluoroethylene resin (tetrafluoride) at a thickness of approximately 1 μm. The width of the printing tape (vertical dimension inFIG.10) was 12 mm, and the characters ABC were printed in 22-point Gothic type using the same printing device for both tests. Printing tape according to both the comparative example and the example of the embodiment were printed in black characters and left for seven days under the high-temperature and high-humidity conditions of 50° C. and 90% humidity, after which the printing characteristics were evaluated. A Macbeth densitometer (with black filter) was used to evaluate the printing characteristics by measuring optical density (OD values).

As shown inFIG.10, the black color forming the characters on the printed tape according to the comparative example disappeared after being exposed for seven days to high temperature and high humidity. On the other hand, the black characters remained vibrant in the printed tape according to the example of the embodiment after seven days under high-temperature and high-humidity conditions, with an OD value of 1.2. Thus, a marked difference in resistance to temperature and water (humidity) was observed in the printing tape according to the preferred embodiment and the printing tape according to the comparative example.

Even though the first adhesive layer581of the second tape58is affixed to the second protective layer593of the first tape59after the printing process, the second protective layer593in the printing tape cassette30according to the first embodiment protects the heat-sensitive layer592from the first adhesive layer581. As confirmed in the evaluation results, the resin used to form the second protective layer593in the preferred embodiment can better protect the heat-sensitive layer592from the effects of temperature, humidity, and the like than the resin emulsion and water-soluble resins, such as polyvinyl alcohol, used in the overcoat layer of the conventional printing tape. Further, since the resin used to form the second protective layer593has relatively low polarity, the first adhesive layer581can be made to adhere well to the second protective layer593by forming the first adhesive layer581of an adhesive exhibiting good adhesive properties with nonpolar adherends.

The printing tape cassette30is provided with release paper as the first adhesive layer581. Thus, the printing tape can be affixed to a desired object after peeling off the base material582(release paper).

The surface of the base material582on the first adhesive layer581side is treated with a non-silicone-type release agent. Thus, the printing tape cassette30can decrease blocking between the adhesive in the first adhesive layer581and the base material582and reduce the release force. The surface of the base material582on the side opposite the first adhesive layer581side is also subjected to treatment with a non-silicone-release agent. Thus, the printing tape cassette30can decrease blocking between the adhesive and the base material582and can reduce the release force, even when the first adhesive layer581is affixed to the surface of the base material582on the opposite side of the first adhesive layer581.

The second tape258according to the second variation includes the double-sided tape base material571as the base material affixed to the first adhesive layer581. The printing tape cassette30in this variation also includes the second adhesive layer572affixed to the side of the double-sided tape base material571opposite the first adhesive layer581, and the release paper573affixed to the second adhesive layer572. With the printing tape cassette30according to the second variation, the thickness, strength, and the like of the printing tape configured by affixing the second tape258to the first tape59can be adjusted according to the double-sided tape base material571. The printing tape of the printing tape cassette30can be affixed to a desired object after peeling off the release paper573.

In the first embodiment, the printing tape cassette30is mounted in the cassette housing section8of the printing device1, which includes the thermal head10, and the second protective layer593of the section of the first tape59positioned between the opening34aand the guide parts36confronts the thermal head10. Accordingly, the printing tape cassette30can facilitate the transfer of heat from the thermal head10to the heat-sensitive layer592to produce color in the heat-sensitive layer592properly. Further, since second protective layer593is formed of a material that transfers heat to the heat-sensitive layer592, the printing tape cassette30can transfer heat from the thermal head10to the heat-sensitive layer592to produce color in the heat-sensitive layer592.

When the printing tape cassette30according to the first variation is mounted in the cassette housing section8of the printing device1, the first protective layer591of the first tape59confronts the thermal head10. Accordingly, the printing tape cassette30can easily transfer heat from the thermal head10to the heat-sensitive layer592to produce color in the heat-sensitive layer592properly. Further, since first protective layer591of the printing tape cassette30is formed of a material that transfers heat to the heat-sensitive layer592, the printing tape cassette30can transfer heat from the thermal head10to the heat-sensitive layer592to produce color in the heat-sensitive layer592.

Next, a printing tape cassette109according to a second embodiment of the present invention and a printing device4in which the printing tape cassette109is mounted will be described with reference toFIGS.6through9. In the following description, the lower side, upper side, left side, and right side inFIG.6are respectively defined as the front side, rear side, left side, and right side of the printing device4and the printing tape cassette109.

7. Structure of the Printing Device4According to a Second Embodiment

As shown inFIG.6, the printing device4is provided with a main unit81, a cover (not shown), an operating section82, a window section83, a display unit84, and a cutter lever85. The main unit81is a case formed of a synthetic resin in a general elliptical shape that is elongated vertically. The cover is detachably mounted on the bottom of the main unit81so as to cover the entire bottom surface (the surface on the opposite side of the surface that the user faces when operating the printing device4). The operating section82includes character keys for alphabetic and numeric characters and symbols, and various function keys. The window section83is a region elongated in the left-right direction and inset in the top surface of the main unit81at the approximate center thereof. The display unit84is disposed in the bottom of the window section83. The display unit84can display inputted alphanumeric characters and symbols. The cutter lever85is provided in the side surface of the main unit81on the left side of the display unit84. When the user pushes the cutter lever85inward (rightward), a cutting blade90described later can cut printing tape discharged through a tape discharge opening (not shown) formed in the rear surface of the main unit81.

Next, the internal structure of the main unit81in the region covered by the cover will be described. As shown inFIG.7, a cassette housing section130is provided inside the main unit81in a region corresponding to the cover. When the cover is removed, the printing tape cassette109can be freely inserted into and removed from the cassette housing section130. The cassette housing section130is formed as a depression that substantially corresponds to the shape of a top surface111of a cassette case110described later when the printing tape cassette109is mounted in the cassette housing section130.

The cassette housing section130is also provided with a conveying mechanism that conveys printing tape120drawn out from the printing tape cassette109, a printing mechanism that prints characters and the like on the surface of the tape, and the like. A head holder86is fixedly disposed on the left side of the cassette housing section130. A thermal head105provided with heating elements (not shown) is mounted in the head holder86.

As shown inFIG.7, an arm-like platen holder88is pivotably supported about a support shaft87provided on the left side of the head holder86. A platen roller89is rotatably supported on the distal end (rear end) of the platen holder88. The platen roller89is disposed so as to be capable of contacting and separating from the thermal head105when the platen holder88pivots. When the cover (not shown) has been removed, a torsion spring (not shown) urges the platen holder88in an outward direction (clockwise in the bottom view ofFIG.7) toward a standby position (not shown). In the standby position, the platen holder88is in contact with a position fixing part106. When the cover is assembled on the rear surface section of the main unit81, a protruding part on the inside of the cover is wedged between the side surface of the platen holder88and the position fixing part106, rotating the platen holder88toward the thermal head105against the urging force of the torsion spring. At this time, the platen holder88is fixed in the operating position shown inFIG.7through contact with the inner surface of the protruding part. When the platen holder88has been rotated toward the printing tape cassette109and fixed in the operating position, the platen roller89presses a section of the printing tape120in the printing tape cassette109against the thermal head105. By rotating the platen roller89while the platen holder88is in the operating position, the platen roller89can convey the printing tape120from the printing tape cassette109and discharge the printing tape120from the main unit81. A cutting blade90is disposed in the left-rear corner of the cassette housing section130downstream of the platen roller89in the tape-conveying direction. The cutting blade90cuts the printing tape120at a prescribed position when the user presses the cutter lever85.

8. Structure of the Printing Tape Cassette109According to the Second Embodiment

Next, the structure of the printing tape cassette109according to the second embodiment will be described with reference toFIGS.7through9. As shown inFIGS.7and8, the printing tape cassette109is provided with a cassette case110, and the printing tape120. Overall, the cassette case110is a substantially rectangular parallelepiped (box-shaped) housing with corners that are rounded in a plan view. The cassette case110is a box-like casing that includes a top surface111and a bottom surface113constituting a pair of rectangular-shaped planar surfaces oppositely arranged in the front-rear direction, and a side surface112formed at a prescribed width along the outer edges of the top surface111and bottom surface113(in this example, four side surfaces including the top surface, bottom surface, left side surface, and right side surface). The combination of the top surface111, the bottom surface113, and the side surface112defines an internal space. The printing tape120is accommodated in the internal space and wound in a roll. In the cassette case110, the side surface112need not enclose the entire peripheries of the top surface111and bottom surface113. For example, an opening may be provided in a portion of the side surface112(the rear surface, for example) that exposes the interior of the cassette case110, and a boss connecting the top surface111to the bottom surface113may be provided in a position confronting this opening. In the second embodiment, the front-rear dimension of the cassette case110(i.e., the direction in which the top surface111and bottom surface113oppose each other) substantially corresponds to the direction in which the printing tape cassette109is inserted into and removed from the cassette housing section130.

The side surface112is provided with an arm part92, an opening108, a guide part107, and a tape discharge part99. The arm part92extends diagonally leftward and rearward from the left-front portion of the printing tape cassette109. The opening108is formed in the distal end (rear end) of the arm part92extending vertically. A conveying path for guiding conveyance of the printing tape120is formed in the arm part92. After the printing tape120is guided along this conveying path, the printing tape120is discharged through the opening108into a head insertion section117(and more specifically, an opening96). Thus, the opening108is provided in the side surface112and constitutes the portion in the cassette case110through which the printing tape120guided along the prescribed conveying path passes from the inside to the outside of the cassette case110.

The guide part107is provided on the upstream side of the opening108formed in the side surface112on the left side of the printing tape cassette109. The guide part107is an opening that guides the printing tape120discharged out through the opening108toward the tape discharge part99. The printing tape120passes from the outside to the inside of the cassette case110through the guide part107. The tape discharge part99is an opening formed in the left-rear corner of the cassette case110. The tape discharge part99extends vertically. After the printing tape120has passed from the outside to the inside of the cassette case110through the guide part107, the printing tape120can pass from the inside to the outside of the cassette case110through the tape discharge part99.

The head insertion section117is a rectangular space formed between the opening108and guide part107. The head insertion section117is elongated vertically in a left side view and penetrates the printing tape cassette109in the vertical direction. The head insertion section117is provided in a leftwardly biased position in the cassette case110(i.e., a position biased toward the side opposite the center of the roll formed by the printing tape120). The head holder86that supports the thermal head105of the printing device4is inserted into the head insertion section117. After the printing tape120has passed from the inside to the outside of the cassette case110through the opening108, the thermal head105prints on the printing tape120in a position between the opening108and guide part107where the printing tape120is exposed to the outside of the cassette case110.

The printing tape120is wound about a tape spool121provided in the printing tape cassette109to form a tape roll that is accommodated in the cassette case110. As shown inFIG.9(A), the printing tape120is configured of a first protective layer122, a heat-sensitive layer123, a second protective layer124, a first adhesive layer125, and a release paper126, as described in the first embodiment. The first protective layer122is provided on the heat-sensitive layer123. The first protective layer122transmits light. The first protective layer122is formed of a material that transfers heat to the heat-sensitive layer123. The heat-sensitive layer123produces color at temperatures within a prescribed range. The second protective layer124is provided on the side of the heat-sensitive layer123opposite the first protective layer122. The second protective layer124includes at least one resin from among fluorine-based resins, silicone-based resins, olefin-based resins, polyester-based resins, epoxy/polyester-based resins, and silicon-based resins. The first adhesive layer581includes at least one adhesive from among an emulsion-type adhesive containing an acrylic polymer and a rubber-based adhesive and compounded with a tackifying resin, silicon-based adhesive, and rubber-based adhesive. The first adhesive layer125is bonded to the side of the second protective layer124opposite the heat-sensitive layer123. The release paper126is bonded to the surface of the first adhesive layer125on the side opposite the surface bonded to the second protective layer124. In the preferred embodiment, the surface of the release paper126on the first adhesive layer125side is subjected to the same non-silicone-based release treatment described in the first embodiment. In other words, a surface of the release paper126on the first adhesive layer125side is subjected to a non-silicone-based release treatment.

9. Third Variation of the Printing Tape Cassette109and Printing Tape120According to the Second Embodiment

FIG.9(B)shows a printing tape220according to a third variation of the printing tape120in the printing tape cassette109of the second embodiment. As shown inFIG.9(B), the printing tape220may be provided with a base material127and a second adhesive layer128between the first adhesive layer125and release paper126. The base material127is affixed to the surface of the first adhesive layer125on the opposite side of the second protective layer124. The second adhesive layer128is affixed to the surface of the base material127on the side opposite the first adhesive layer125. The release paper126is affixed to the surface of the second adhesive layer128on the side opposite the base material127.

In the second embodiment and the third variation, the printing tape120, heat-sensitive layer123, first protective layer122, second protective layer124, first adhesive layer125, and release paper126are respective examples of the printing tape, the heat-sensitive layer, the first protective layer, the second protective layer, the first adhesive layer, and the release paper in the present invention. In the third variation, the base material127, release paper126, and second adhesive layer128are respective examples of the base material, the release paper, and the second adhesive layer in the invention. The cassette case110, top surface111, bottom surface113, and side surface112are respective examples of the cassette case, the first surface, the second surface, and the third surface in the invention.

In the printing tape120according to the second embodiment, the second protective layer124protects the heat-sensitive layer123from the first adhesive layer125. The resin used to form the second protective layer124can better protect the heat-sensitive layer123from the effects of temperature, humidity, and the like than the resin emulsion and water-soluble resins, such as polyvinyl alcohol, used in the overcoat layer of the conventional printing tape. Further, since the resin used to form the second protective layer124has relatively low polarity, the first adhesive layer125can be made to adhere well to the second protective layer124by forming the first adhesive layer125of an adhesive exhibiting good adhesive properties with nonpolar adherends.

The printing tape120is provided with the release paper126on the side of the first adhesive layer125opposite the second protective layer124. Thus, the printing tape120can be affixed to a desired object after peeling off the release paper126.

With the printing tape120, the surface of the release paper126on the first adhesive layer125side is treated with a non-silicone-type release agent. Thus, the printing tape120can decrease blocking between the adhesive in the first adhesive layer125and the release paper126and reduce the release force.

The printing tape220according to the third variation is provided with the base material127on the side of the first adhesive layer125opposite the second protective layer124, the release paper126, and the second adhesive layer128disposed between the base material127and release paper126. With the printing tape220having this configuration, the thickness, strength, and the like of the printing tape220can be adjusted according to the base material127. The printing tape220can be affixed to a desired object after peeling off the release paper126.

When the printing tape cassette109is mounted in the cassette housing section130of the printing device4, which includes the thermal head105, the first protective layer122of the printing tape120confronts the thermal head105between the opening108and guide part107. Accordingly, the printing tape cassette109can better facilitate the transfer of heat from the thermal head105to the heat-sensitive layer123than when the side of the printing tape120opposite the first protective layer122confronts the thermal head105, thereby suitably producing color in the heat-sensitive layer123.

The first protective layer122is formed of a material that transfers heat to the heat-sensitive layer123. Accordingly, the printing tape cassette109can transfer heat from the thermal head105to the heat-sensitive layer123to produce color in the heat-sensitive layer123.

Printing tape and printing tape cassette in the present invention are not limited to the embodiments as described above. The present invention may be worked by making various changes within the spirit and scope of the invention. For example, following changes may be added appropriately.

The structure of the printing device in which the printing tape cassette is mountable may be modified as needed. Further, the size, shape, material, and the like of the cassette case constituting the printing tape cassette may be modified as needed. The printing tape120need not be accommodated in the printing tape cassette109. The printing tapes120and50need not be provided with release paper. When the printing tape50is provided with release paper, it is sufficient to treat just one surface of the release paper with a non-silicone-type release agent and unnecessary to treat both surfaces of the release paper. When the printing tape120is provided with release paper, the release paper need not be treated with a release agent. The printing tapes50and120need not be wound into rolls. The conveying path for conveying printing tape within the cassette case may be modified as needed. The printing tape cassette may be provided with the platen roller. The arrangement of the thermal head relative to the printing tape cassette and the printing tape (first tape) when the printing tape cassette is mounted in the printing device may be modified as needed.