PatentDe  


Dokumentenidentifikation EP1378370 30.11.2006
EP-Veröffentlichungsnummer 0001378370
Titel Wärmeempfindliches Übertragungsaufzeichnungsmedium und Druckerzeugnis
Anmelder Kabushiki Kaisha Toshiba, Tokio/Tokyo, JP
Erfinder Washizuka, Toshiba Kabushiki Kaisha, Junichi, Minato-ku Tokyo, JP
Vertreter derzeit kein Vertreter bestellt
DE-Aktenzeichen 60215478
Vertragsstaaten AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LI, LU, MC, NL, PT, SE, TR
Sprache des Dokument EN
EP-Anmeldetag 13.06.2002
EP-Aktenzeichen 030231476
EP-Offenlegungsdatum 07.01.2004
EP date of grant 18.10.2006
Veröffentlichungstag im Patentblatt 30.11.2006
IPC-Hauptklasse B41M 5/52(2006.01)A, F, I, 20060309, B, H, EP
IPC-Nebenklasse B41M 5/44(2006.01)A, L, I, 20060309, B, H, EP   B41M 7/00(2006.01)A, L, I, 20060309, B, H, EP   

Beschreibung[en]

The present invention relates to a heat transfer recording medium having an image receiving layer formed on a support member, and capable of forming an image by hot-melt ink and thermally adhering the layer onto a recording medium such as paper or plastic, and to a printed product obtained by using this heat transfer recording medium.

A sublimation type heat transfer recording method is most often used as a method of recording a face image for personal authentication onto an image display body such as a license, employee's ID card, member's card, or credit card.

In this sublimation type heat transfer recording method, a sublimating ink ribbon formed by coating a support sheet with ink containing a sublimating (or heat flowing) dye such that heat transfer is possible, is overlayed on a recording medium having an image receiving layer made of a thermoplastic resin capable of accepting the sublimating dye. The heat transfer ribbon is selectively heated on the basis of image data by a thermal head or the like, thereby forming a desired image on the recording medium by sublimation type heat transfer recording. It is widely known that color images superior in tone reproduction can be easily recorded by this method. However, this sublimation type heat transfer recording method has the problems related to the durability of a card. For example, an image is easily scratched because it is formed near the face region of thermoplastic resin layer, the dye sublimates again to lower the image density with time, and ultraviolet radiation decomposes the dye to change the tone of color of an image.

A melting type heat transfer recording method is also usable. In this method, a hot-melt ink transfer ribbon formed by coating a support sheet with hot-melt ink in which a coloring pigment or dye is dispersed in a binder such as a resin or wax, is overlayed on a recording medium having an image receiving layer made of a thermoplastic resin capable of accepting the hot-melt ink transfer ribbon. The heat transfer ribbon is selectively heated on the basis of image data by a thermal head or the like, thereby recording a desired image by transferring the binder-containing hot-melt ink onto the recording medium. In this method, inorganic or organic pigments generally having high lightfastness can be selectively used as the coloring material. Also, by improving the resin or wax used as the binder, it is possible to provide images hard to scratch and superior in solvent resistance. In addition, special high-security ink is readily formable by mixing a functional material such as a fluorescent pigment or magnetic substance into the ink. The image receiving layer can be any recording medium provided that the medium has a surface adhesive to the binder. So, the image receiving layer can be chosen from various recording media. As described above, this melting type heat transfer recording method is advantageous for the sublimation type heat transfer method.

Still another method is proposed in which an image is formed on a transparent transfer type image receiving layer formed on a base film by the sublimation heat transfer recording method or the melting type heat transfer recording method described above, and this transfer type image receiving layer on which the image is recorded is thermally transferred onto a recording medium such as paper. In this method, after transferring the transfer type image receiving layer itself can function as a surface protective film, so the mechanical strength of the surface is high. Also, by improving the smoothness of the transfer type image receiving layer surface and thereby increasing the affinity to the ink layer, images excellent in tone reproduction can be formed even by the melting type heat transfer method.

Unfortunately, if a printed product on which a transfer type image receiving layer is formed by the above method is stored for long time periods in contact with a film containing a plastic material, e.g., a vinyl chloride resin, such as used in a transparent resin cover, this plastic material moves to the transfer type image receiving layer and is fused to the vinyl chloride resin or the like. If this plastic material is peeled, the transfer type image receiving layer is removed from the final recording medium. Alternatively, if a sublimating ink image is recorded on a printed product, the sublimating dye becomes readily diffusible. This smears the contour of the image or discolors the image.

That is, a transfer type image receiving layer formed by the conventional method cannot be stored for long time periods if a resin film containing a plastic material is overlayed on the layer.

Also, the melting type heat transfer recording method basically performs ink adhesion and uses a dot area modulation tone recording method in which tone recording is performed by changing the sizes of transferred dots. Therefore, the method is very sensitive to the surface unevenness of a recording medium to which an image is to be transferred. If the surface is uneven, inferior transfer occurs to make dot size control impossible, resulting in poor tone reproduction.

Various proposals have been made to solve the above problems. One proposed method uses a recording medium having a porous image receiving layer. In this method, fine pores are formed in an image receiving layer of a recording medium, and hot-melt ink is transferred into these fine pores by permeation.

This method can provide images superior in tone reproduction. However, a porous image receiving layer generally has low mechanical strength, so the surface is scratched when brought into contact with various rollers and a convey path in a printing apparatus, resulting in image defects.

In another proposed method, an image is formed on a resin layer obtained by forming a transparent image receiving layer/adhesive layer on a film base, and this image receiving layer/adhesive layer is heated and pressurized to adhere or heated transfer onto a base such as paper or plastic to which the image is to be given. In this method, no fine pores are formed in the image receiving layer, so the mechanical strength of the surface is high. In addition, by improving the smoothness of the resin layer surface and thereby increasing the affinity to the ink layer, images excellent in tone reproduction can be formed even by the melting type heat transfer method.

Unfortunately, the above method has the problem that if a low-softening-temperature resin having high adhesion to paper or plastic is used as the image receiving layer/adhesive layer, the reproducibility of the recording image density becomes unstable under the same recording conditions. This is so because a state (center omission) in which no ink is present in the centers of pixel points constructing a transferred ink image occurs.

To prevent this center omission of each pixel point, a resin having a high softening temperature can be used in the image receiving layer/adhesive layer. However, this lowers the adhesion to the base such as paper or plastic.

As described above, a melting type heat transfer recording image receiving layer formed by the conventional method cannot prevent center omission and ensure sufficient adhesion to paper or plastic at the same time.

US 5,981,077 discloses a heat transfer recording medium, comprising a support member and an image receiving layer formed on said support member, wherein said image receiving layer comprises a resin component having a glass transition temperature lower than 0°C, and a resin component having a glass transition temperature higher or equal to 0°C, and/or a resin having a molecular weight from 10000 to 500000, and a resin having a molecular weight from 10000000 to 60000000.

It is the first object of the present invention to provide a heat transfer recording medium having an image receiving layer excellent in image printing characteristics when a melting type heat transfer recording method is used, and a protective film which, even when stored as it is overlayed on a resin containing a plastic material, causes neither fusion to the resin nor deterioration of an image and hence can be stably stored for long time periods.

It is the second object of the present invention to provide a printed product which has excellent image printing characteristics when a melting type heat transfer recording method is used, and which, even when stored as it is overlayed on a resin containing a plastic material, causes neither fusion to the resin nor deterioration of an image and hence can be stably stored for long time periods.

It is the third object of the present invention to provide a heat transfer recording medium which has excellent image printing characteristics when a melting type heat transfer recording method is used, from which a stable image density is obtained whenever recording is performed, which can form a high-quality image superior in tone reproduction, and which has sufficient adhesion to a base.

According to a first aspect of the invention, there is provided a heat transfer recording medium for recording an image by using hot-melt ink, comprising a support member, and a hot-melt ink image receiving layer/adhesive layer formed on the support member and containing at least first and second resin components, the first resin component having a number-average molecular weight of 16,000 or more and having a glass transition point of -20°C to 20°C, the second resin component having a number-average molecular weight of 16, 000 or less and a glass transition point of 50°C to 180°C, and a weight mixing ratio of the first resin component to the second resin component being 1 : 9 to 5 : 5.

According to a second aspect of the invention, there is provided a printed product comprising a base, hot-melt ink image layer, and hot-melt ink image receiving layer/adhesive layer in turn,

wherein the hot-melt ink image receiving layer/adhesive layer contains a first resin component having a number-average molecular weight of 16,000 or more and having a glass transition point of -20°C to 20°C and a second resin component having a number-average molecular weight of 16, 000 or less and a glass transition point of 50°C to 180 °C, a weight mixing ratio of the first resin component to the second resin component being 1 : 9 to 5 : 5.

The invention may also be a sub-combination of these described features.

The invention can be more fully understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:

  • FIG. 11 is a schematic sectional view showing an example of the structure of a heat transfer recording medium of the present invention;
  • FIG. 12 is a schematic sectional view showing an example of the structure of a printed product of the present invention;
  • FIG. 13 is a schematic sectional view showing the structure of another example of the third heat transfer recording medium of the present invention;
  • FIG. 14 is a schematic sectional view showing another example of the structure of a printed product of the present invention;
  • FIG. 15 is a schematic sectional view showing the structure of still another example of the heat transfer recording medium of the present invention; and
  • FIG. 16 is a schematic sectional view showing another example of the structure of a printed product of the present invention.

The heat transfer recording medium of the present invention comprises a support member, and a hot-melt ink image receiving layer/adhesive layer formed on the support member and containing first and second resin components.

The first resin component has a number-average molecular weight of 16,000 or more and, has a glass transition point Tg1 of -20°C to 20°C.

The second resin component has a number-average molecular weight of 16,000 or less and a glass transition point Tg2 of 50°C to 180°C.

The weight mixture ratio of the first resin component to the second resin component is 1 : 9 to 5 : 5.

In this hot-melt ink image receiving layer/adhesive layer, an image layer can be formed by using hot-melt ink having the glass transition point Tg.

A heat transfer recording medium in which an image layer is formed is transferred onto a base, and the support member is peeled. The result is a printed product having the base, the image layer formed on the base by the hot-melt ink having the glass transition point Tg, and the hot-melt ink image receiving layer/adhesive layer by which the image layer is received and which is adhered together with this image layer onto the base.

When the support member is not peeled, a printed product is obtained which includes the base, the image layer formed on the base by the hot-melt ink having the glass transition point Tg, the hot-melt ink image receiving layer/adhesive layer by which the image layer is received and which is adhered together with this image layer onto the base, and the support member. This support member can function as, e.g., a protective layer.

The first resin component contributes to the adhesive action, together with the second resin component, during thermal adhesion. Therefore, it is possible to assure sufficient adhesion properties which cannot be obtained by the adhesive action by the first resin component alone. The second resin component is also superior in a function of accepting hot-melt ink.

In the present invention, the hot-melt ink image receiving layer/adhesive layer containing the first and second resin components at a predetermined weight mixing ratio is used. This improves the adhesion of the hot-melt ink image receiving layer/adhesive layer to the base such as paper. In addition, since no pixel point center omission occurs, the image density is stable whenever recording is performed, so high-quality images excellent in tone reproduction can be formed.

If the number-average molecular weight of the first resin component is less than 16,000 and the glass transition point Tg1 exceeds Tg - 80°C, no sufficient adhesion of the hot-melt ink image receiving layer/adhesive layer to the base can be obtained.

The number-average molecular weight of the first resin component is preferably 16,000 to 30,000. If this number-average molecular weight exceeds 30,000, sufficient adhesion strength intends to not be achieved. The glass transition point of the first resin component is preferably -20°C to 20°C. If this glass transition point is less than -20°C, pixel shape and tone recording properties tend to be deteriorated.

If the second resin component has a number-average molecular weight exceeding 16,000 and the glass transition point Tg2 less than Tg - 50°C, pixel point center omission occurs during image printing.

The number-average molecular weight of the second resin component is favorably 1,500 to 16,000. If this number-average molecular weight is less than 1,500, sufficient adhesion strength intends to not be achieved. The glass transition point of the second resin component is favorably 50 to 180°C. If this glass transition point exceeds 180°C, excessive heat amount tends to be required for thermal adhesion.

The combination of the first and second resin components can be selected from combinations of the same type or different types of resins having different glass transition points and different molecular weights, provided that these resins have predetermined molecular weights and glass transition points described above.

The present invention will be described in detail below with reference to the accompanying drawing.

FIG. 11 is a schematic sectional view showing an example of the structure of the heat transfer recording medium of the present invention.

As shown in FIG. 11, this heat transfer recording medium 50 has a structure in which a hot-melt ink image receiving layer/adhesive layer 42 containing first and second resin components at a mixing ratio of 1 : 9 to 5 : 5 is stacked on a support sheet 41 such as a polyester film. The first resin component has a number-average molecular weight of 16,000 or more and, letting Tg be the glass transition point of hot-melt ink, has a glass transition point of Tg - 80°C or less. The second resin component has a number-average molecular weight of 16,000 or less and a glass transition point of 50°C or more.

This hot-melt ink image receiving layer/adhesive layer 42 can be formed by preparing a resin coating solution containing the resins and a preferred solvent, forming a layer of this resin coating solution, and drying the layer. The coating and drying are done by a method which forms a layer of a coating solution and dries the layer. Examples are gravure coating, reverse coating, die coating, wire bar coating, and hot-melt coating.

After an image is formed by hot-melt ink on this heat transfer recording medium 50, the heat transfer recording medium 50 can be thermally adhered to a base such as paper or plastic.

FIG. 12 is a schematic sectional view showing an example of the structure of a printed product obtained by using the heat transfer recording medium 50 shown in FIG. 11.

As shown in FIG. 12, this printed product 51 has a structure in which an image layer 43 formed by hot-melt ink and a resin layer 42 consisting of at least two components are stacked in this order on a base 44 such as paper.

The image layer 43 can be formed by placing a hot-melt ink ribbon on the surface of the hot-melt ink image receiving layer/adhesive layer 42 of the heat transfer recording medium 50, and performing heat transfer recording by using a heat recording means such as a thermal head. After the image layer 43 is formed, the paper base 44 is placed on this image layer 43, and the resultant structure is passed through, e.g., a heat roller capable of simultaneously applying heat and pressure, thereby entirely heating the hot-melt ink image receiving layer/adhesive layer 42 or selectively heating a desired pattern by using, e.g., hot stamp. In this manner, the whole or part of the hot-melt ink image receiving layer/adhesive layer 42 can be thermally adhered onto the base 44. After that, the support sheet 41 is peeled to obtain the printed product 47 shown in FIG. 12.

In this heat transfer recording medium of the present invention, an easy-adhesion layer or a peeling layer can also be formed as an intermediate layer between the support member and the hot-melt ink image receiving layer/adhesive layer.

When the hot-melt ink image receiving layer/adhesive layer is thermally adhered onto the base and the support member formed on the hot-melt ink image receiving layer/adhesive layer is peeled off as described above, the peeling between this support member and the hot-melt ink image receiving layer/adhesive layer can be further improved by the formation of a peeling layer.

The support member can also be used as a protective layer without being peeled. When the support member is to be used as a protective layer, the adhesion between the support member and the hot-melt ink image receiving layer/adhesive layer can be further improved by the formation of an easy-adhesion layer.

Protective layers can be further formed between the support member and the hot-melt ink image receiving/adhesive layer, between the peeling layer and the hot-melt ink image receiving layer/adhesive layer, and between the support member and the easy-adhesion layer. As these protective layers, it is possible to use as the protective layer, one containing mainly a resin selected from the group consisting of a polybutyral resin, phenoxy resin, and polyvinylacetal resin.

FIG. 13 is a schematic sectional view showing the structure of another example of the heat transfer recording medium of the present invention.

As shown in FIG. 13, this heat transfer recording medium 60 has the same structure as the heat transfer recording medium shown in FIG. 11, except that a peeling layer 45 made of, e.g., wax and an ethylene-vinyl acetate copolymer resin is formed between a support sheet 41 and a hot-melt ink image receiving layer/adhesive layer 42.

This peeling layer 45 can be formed by, e.g., gravure coating, reverse coating, die coating, wire bar coating, or hot-melt coating.

FIG. 14 is a schematic sectional view showing another example of the structure of a printed product obtained using the heat transfer recording medium 60 shown in FIG. 13.

As shown in FIG. 14, this printed product 61 has the same structure as the printed product 51 shown in FIG. 12, except that the peeling layer 45 is formed on the hot-melt ink image receiving layer/adhesive layer 42.

Referring to FIG. 14, the peeling layer 45 is formed on the hot-melt ink image receiving layer/adhesive layer 42. This peeling layer 45 can partially remain on the hot-melt ink image receiving layer/adhesive layer 42 or can be peeled off together with the support sheet 41. When the peeling layer 45 is removed, the obtained printed product has the same structure as the printed product 51 shown in FIG. 12.

FIG. 15 is a schematic sectional view showing the structure of still another example of the heat transfer recording medium of the present invention.

As shown in FIG. 15, this heat transfer recording medium 70 has the same structure as the heat transfer recording medium shown in FIG. 11, except that an easy-adhesion layer 45 made of, e.g., ethylene vinylacetate copolymer resin, acryl resin, or polyester resin is formed between a support sheet 41 and a hot-melt ink image receiving layer/adhesive layer 42.

This easy-adhesion layer 46 can be formed by, e.g., gravure coating, reverse coating, die coating, wire bar coating, or hot-melt coating.

FIG. 16 is a schematic sectional view showing another example of the structure of a printed product using the heat transfer recording medium 70 shown in FIG. 15.

As shown in FIG. 16, this printed product 71 has the same structure as the printed product 61 shown in FIG. 14, except that an easy-adhesion layer 46 and a support sheet 41 are formed in this order on a hot-melt ink image receiving layer/adhesive layer 42.

A resin used in the peeling layer desirably has a properly controlled adhesive force to the support member. If this adhesive force is excessively large, the support member can become difficult to peel after thermal adhesion. If the adhesive force is too small, the support member can be easily peeled, but an undesired resin layer which is not thermally adhered often remains on the hot-melt ink image receiving layer/adhesive layer.

Examples of the resin having proper adhesive force appropriate as the peeling layer are wax, vinyl acetate resin, ethylene-vinyl acetate copolymer resin, acrylic resin, silicone resin, polyester resin, and mixtures of these resins.

As the wax, it is possible to preferably use polyethylene wax, carnauba wax, or the like. Practical examples are Hi-Mic-2065, Hi-Mic-1045, Hi-Mic-2045, PALVAX-1230, PALVAX-1330, PALVAX-1335, PALVAX-1430, BONTEX-0011, BONTEX-0100, and BONTEX-2266 (trademarks) manufactured by NIPPON SEIRO CO., LTD.

Practical examples of the vinyl acetate resin are SAKNOHOL SN-04, SAKNOHOL SN-04S, SAKNOHOL SN-04D, SAKNOHOL SN-09A, SAKNOHOL SN-09T, SAKNOHOL SN-10, SAKNOHOL SN-10N, SAKNOHOL SN-17A, ASR CH-09, and ASR CL-13 (trademarks) manufactured by DENKI KAGAKU KOGYO K.K., Movinyl DC (trademark) manufactured by Kurarianto Polymers K.K., and Cevian A530, Cevian A700, Cevian A707, Cevian A710, Cevian A712, and Cevian A800 (trademarks) manufactured by Daiseru Kaseihin K.K.

Practical examples of the ethylene-vinyl acetate copolymer resin are EVAFLEX 45X, EVAFLEX 40, EVAFLEX 150, EVAFLEX 210, EVAFLEX 220, EVAFLEX 250, EVAFLEX 260, EVAFLEX 310, EVAFLEX 360, EVAFLEX 410, EVAFLEX 420, EVAFLEX 450, EVAFLEX 460, EVAFLEX 550, and EVAFLEX 560 (trademarks) manufactured by Du Pont-Mitsui Polychemicals Co., Ltd., Movinyl 081F (trademark) manufactured by Kurarianto Polymers K.K., EVATATE D3022, D3012, D4032, and CV8030 (trademarks) manufactured by SUMITOMO CHEMICAL CO., LTD., Hirodain 1800-5, Hirodain 1800-6, Hirodain 1800-8, Hirodain 3706, and Hirodain 4309 (trademarks) manufactured by Hirodain Kogyo K.K., and BOND CZ250 and BOND CV3105 (trademarks) manufactured by KONISHI K.K.

Practical examples of the acrylic resin are Cevian A45000, Cevian A45610, Cevian A46777, and Cevian A4635 (trademarks) manufactured by Daiseru Kaseihin K.K., and Dianal BR-80, Dianal BR-83, Dianal BR-85, Dianal BR-87, Dianal BR-101, Dianal BR-102, Dianal BR-105, and Dianal BR-106 (trademarks) manufactured by Mitsubishi Rayon Co., Ltd.

A practical example of the silicone resin is Tosguard 510 (trademark) manufactured by Toshiba Silicones K.K.

Practical examples of the polyester resin are VYLON 200, VYLON 220, VYLON 240, VYLON 245, VYLON 280, VYLON 296, VYLON 530, VYLON 560, VYLON 600, VYLONAL MD1100, VYLONAL MD1200, VYLONAL MD1245, VYLONAL MD1400, and VYLONAL GX-W27 (trademarks) manufactured by TOYOBO CO., LTD., and ELITEL UE-3300, ELITEL UE-3320, ELITEL UE-3350, ELITEL UE-3370, and ELITEL UE-3380 (trademarks) manufactured by UNITIKA, LTD.

The easy-adhesion layer must have large adhesive force between the base film and both the support member and the resin layer. A resin satisfying this requirement is selected in accordance with the materials of the support member and hot-melt ink image receiving layer/adhesive layer. Examples are an ethylene-vinyl acetate copolymer resin, acrylic resin, polyester resin, and mixtures of these resins.

Practical examples of the ethylene-vinyl acetate copolymer resin are EVAFLEX 45X, EVAFLEX 40, EVAFLEX 150, EVAFLEX 210, EVAFLEX 220, EVAFLEX 250, EVAFLEX 260, EVAFLEX 310, EVAFLEX 360, EVAFLEX 410, EVAFLEX 420, EVAFLEX 450, EVAFLEX 460, EVAFLEX 550, and EVAFLEX 560 (trademarks) manufactured by Du Pont-Mitsui Polychemicals Co., Ltd., Movinyl 081F (trademark) manufactured by Kurarianto Polymers K.K., EVATATE D3022, D3012, D4032, and CV8030 (trademarks) manufactured by SUMITOMO CHEMICAL CO., LTD., Hirodain 1800-5, Hirodain 1800-6, Hirodain 1800-8, Hirodain 3706, and Hirodain 4309 (trademarks) manufactured by Hirodain Kogyo K.K., and BOND CZ250 and BOND CV3105 (trademarks) manufactured by KONISHI K.K.

Practical examples of the acryl resin are Dianal BR-53, Dianal BR-64, Dianal BR-77, Dianal BR-79, Dianal BR-90, Dianal BR-93, Dianal BR-101, Dianal BR-102, Dianal BR-105, Dianal BR-106, Dianal BR-107, Dianal BR-112, Dianal BR-115, Dianal BR-116, Dianal BR-117, Dianal BR-118, (trademarks) manufactured by Mitsubishi Rayon Co., Ltd.

Practical examples of the polyester resin are VYLON 103, VYLON 220, VYLON 240, VYLON 245, VYLON 270, VYLON 280, VYLON 300, VYLON 500, VYLON 530, VYLON 550, VYLON 560, VYLON 600, VYLON 630, VYLON 650 (trademarks) manufactured by TOYOBO CO., LTD., ELITEL UE-3300, ELITEL UE-3320, ELITEL UE-3350, ELITEL UE-3370, ELITEL UE-3380 (trademarks) manufactured by UNITIKA, LTD.

The first and second resin components of the hot-melt ink image receiving layer/adhesive layer used in the present invention are preferably made of at least one of a polyester resin and acrylic resin.

More preferably, the combination of the first and second resin components is an acrylic resin and polyester resin, or a polyester resin and polyester resin.

Particularly preferably, the combination is polyester resin and polyester resin.

More particularly preferably, the combination is VYLON 300 and ELITEL UE-3350.

Examples of the first resin component used in the hot-melt ink image receiving layer/adhesive layer are an acrylic resin and polyester resin.

Practical examples of the acrylic resin are Dianal BR-102 and Dianal BR-112 (trademarks) manufactured by Mitsubishi Rayon Co., Ltd.

Practical examples of the polyester resin are VYLON 300, VYLON 500, VYLON 530, VYLON 550, VYLON 560, VYLON 630, VYLON 650, VYLON GK130, VYLON GK330, VYLON BX1001, VYLON GM400, VYLON GM460, VYLON GM470, VYLON GM480, VYLON GM900, VYLON GM913, VYLON GM920, VYLON GM925, VYLON GM990, VYLON GM995, VYLON GA1300, VYLON GA3200, VYLON GA3410, VYLON GA5300, VYLON GA5410, VYLON GA6300, VYLON GA6400, VYLON 30P, VYLON UR2300, VYLON UR3200, VYLON UR3210, VYLON UR8700, VYLON UR9500, VYLONAL MD1930, and VYLONAL MD1985 (trademarks) manufactured by TOYOBO CO., LTD., and ELITEL UE-3220, ELITEL UE-3223, ELITEL UE-3230, ELITEL UE-3231, ELITEL UE-3400, ELITEL UE-3700, and ELITEL UE-3800 (trademarks) manufactured by UNITIKA, LTD.

Examples of the resin used as the second resin component are stylene-acryl copolymer resin and a polyester resin.

Practical examples of the polyester resin are VYLON 220, VYLON 240, VYLON 296, VYLON GK250, VYLONAL MD1200, VYLONAL MD1220, VYLONAL MD1250, and VYLONAL MD1500 (trademarks) manufactured by TOYOBO CO., LTD., and ELITEL UE-9200, ELITEL UE-3690, ELITEL UE-3370, ELITEL UE-3380, ELITEL UE-3350, and ELITEL UE-3300 (trademarks) manufactured by UNITIKA, LTD.

Practical examples of stylene-acryl copolymer resin are S-lecP SE-0020, S-lecP SE-0040, S-lecP SE-0070, S-lecP SE-1010, S-lecP SE-1035 (trademarks) manufactured by Sekisui Chemical Co., Ltd.

Examples

Examples of heat transfer recording medium having image receiving layer/adhesive layer containing first and second resin components

Examples 27 - 29 & Comparative Examples 22 - 27

25- µm thick transparent polyester films (trademark: Lumirror Q27, manufactured by TORAY INDUSTRIES, INC.) were prepared. The surfaces of these transparent polyester films were coated with a hot-melt ink image receiving layer/adhesive layer coating solution 1 having the following compositions by using a gravure coater, such that the dried film thickness was 6 µm. The obtained coating films were heated and dried at 120°C for 2 min to form hot-melt ink image receiving layers/adhesive layers, thereby obtaining heat transfer recording media. Compositions of hot-melt ink image receiving layer/adhesive layer coating solution 1 Methylethylketone 40 parts by weight Toluene 40 parts by weight Resin mixtures containing first and second resin components mixed at ratios described in Table 10 to be presented later 20 parts by weight

On the hot-melt ink image receiving layers/adhesive layers of the obtained heat transfer recording media, color images were recorded by a 600-dpi thermal head by using a commercially available hot-melt ink ribbon, thereby obtaining image layers.

After that, commercially available PPC paper was placed on each image layer, and the resultant structure was passed through Laminator LPD2306 City manufactured by Fujipra K.K., thereby thermally adhering the heat transfer recording medium and the PPC paper to obtain a printed product. The roller temperature and the roller rotating speed of the laminator were adjusted to 180°C and 1 m/min, respectively.

Each obtained printed product was tested and evaluated for the pixel point shape and the adhesion strength between the heat transfer recording medium and the PPC paper following the same procedures as in Example 23.

The results are shown in Table 10.

In this example, the printed product was obtained by adhering the support member by the easy-adhesion layer. However, when a printed product is to be obtained by peeling the support member, a tape peeling test using an adhesive tape can also be used. In this tape peeling test, the evaluation was ○ if no hot-melt ink image receiving layer/adhesive layer is sticking to the peeled tape; the evaluation was × if the hot-melt ink image receiving layer/adhesive layer is sticking to the peeled tape.

The results are shown in Table 10.

Examples 30 - 32 & Comparative Examples 28 - 33

One surface of a 25-µm thick transparent polyester film (trademark: Lumirror S10, manufactured by TORAY INDUSTRIES, INC.) was coated with a peeling layer coating solution having the following composition by using a gravure coater, such that the dried film thickness was 1 µm. The coating film was heated and dried at 120°C for 2 min to form a peeling layer. Composition of peeling layer coating solution Methylethylketone 35 parts by weight Toluene 35 parts by weight Vinyl acetate resin (trademark: Cevian A700, manufactured by Daiseru Kaseihin K.K.) 20 parts by weight Polyester resin (trademark: VYLON 220, manufactured by TOYOBO CO., LTD.) 10 parts by weight

Subsequently, on this peeling layer, a hot-melt ink image receiving layer/adhesive layer was formed following the same procedures as in each of Examples 27 to 29 and Comparative Examples 22 to 27, thereby obtaining heat transfer recording media.

By using the obtained heat transfer recording media, printed products were obtained in the same manner as in Example 27.

The obtained images were tested and evaluated for the pixel point shape and the adhesion strength in the same manner as in Example 27.

The results are shown in Table 11 below.

As is apparent from Tables 10 and 11, when the molecular weights, glass transition points, and mixing ratio of the first and second resin components used in the hot-melt ink image receiving layer/adhesive layer fell within the ranges of the present invention, no center omission occurred in the pixel point shape. Therefore, the reproducibility of the recording image density improved, and satisfactory adhesion strength was obtained.

However, as indicated by Comparative Examples 22, 23, 28, and 29, for example, if the amount of the first resin component was too large, the adhesion strength lowered, and, if the amount of the second resin component was too large, pixel point center omission occurred to worsen the recording image density reproducibility. Also, as indicated by Comparative Examples 25 and 31, if the glass transition point of the first resin component was too high, the adhesion strength lowered. As indicated by Comparative Examples 26 and 32, if the molecular weight of the second resin component was too low, pixel point center omission occurred to worsen the recording image density reproducibility. Furthermore, as indicated by Comparative Examples 22 and 28, if the molecular weight of the second resin component was too high, the adhesion strength lowered. As indicated by Comparative Examples 24 and 30, if no first resin component was used, the adhesion strength lowered.

The examples and comparative examples described above demonstrate that if one of the first and second resin components of the hot-melt ink image receiving layer/adhesive layer is lacking, or if any one of the molecular weights, glass transition points, and mixing ratio of the first and second resin components falls outside the range of the present invention, it is impossible to obtain a good pixel point shape, high recording image reproducibility, and sufficient adhesion strength.

As described above, the third heat transfer recording medium of the present invention can stably reproduce a recording image density without causing any pixel point center omission in an image recorded by hot-melt ink, can form a high-quality image superior in tone reproduction, and has sufficient adhesion to the base.

Also, it is possible by using this heat transfer recording medium to obtain the third printed product of the present invention which can stably reproduce a recording image density without causing any pixel point center omission in an image recorded by hot-melt ink, and which has a high-quality image superior in tone reproduction.

It is explicitly stated that all features disclosed in the description are intended to be disclosed separately and independently from each other for the purpose of original disclosure as well as for the purpose of restricting the claimed invention independent of the compositions of the features in the embodiments and/or the claims.


Anspruch[de]
Wärmetransferaufzeichnungsmedium (50) zum Aufzeichnen eines Bilds unter Verwendung einer Heißschmelztinte, das ein Trägerelement (41) und eine Heißschmelztintenbildempfangsschicht/Haftmittelschicht (42), die auf dem Trägerelement (41) ausgebildet ist, umfasst, dadurch gekennzeichnet, dass die Heißschmelztintenbildempfangsschicht/Haftmittelschicht mindestens eine erste und eine zweite Harzkomponente enthält, wobei die erste Harzkomponente ein Zahlenmittel des Molekulargewichts von nicht weniger als 16000 und einen Glasübergangspunkt von -20°C bis 20°C aufweist, wobei die zweite Harzkomponente ein Zahlenmittel des Molekulargewichts von nicht mehr als 16000 und einen Glasübergangspunkt von 50°C bis 180°C aufweist, und das Mischungsverhältnis der ersten Harzkomponente zu der zweiten Harzkomponente, bezogen auf das Gewicht, 1:9 bis 5:5 beträgt. Medium nach Anspruch 1, dadurch gekennzeichnet, dass die erste Harzkomponente ein Zahlenmittel des Molekulargewichts von 16000 bis 30000 aufweist und die zweite Harzkomponente ein Zahlenmittel des Molekulargewichts von 1500 bis 16000 aufweist. Medium nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass es ferner eine Zwischenschicht (45), bei der es sich um eine von einer leicht haftenden Schicht und einer Ablöseschicht handelt, zwischen dem Trägerelement (41) und der Heißschmelztintenbildempfangsschicht/Haftmittelschicht (42) umfasst, wobei die leicht haftende Schicht aus einem Harz zusammengesetzt ist, das aus der Gruppe bestehend aus Ethylen-Vinylacetat-Copolymerharzen, Acrylharzen, Polyesterharzen und Gemischen dieser Harze ausgewählt ist. Medium nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass die Heißschmelztintenbildempfangsschicht/Haftmittelschicht (42) aus mindestens einem von einem Polyesterharz und einem Acrylharz hergestellt ist. Gedrucktes Produkt (51), das eine Basis (44), eine Heißschmelztintenschicht (43) und eine Heißschmelztintenbildempfangsschicht/Haftmittelschicht (42) umfasst,

dadurch gekennzeichnet, dass die Heißschmelztintenbildempfangsschicht/Haftmittelschicht (42) eine erste Harzkomponente und eine zweite Harzkomponente enthält, wie sie im Anspruch 1 definiert sind.
Produkt nach Anspruch 5, dadurch gekennzeichnet, dass es ferner eine Schutzschicht (45) auf der Heißschmelztintenbildempfangsschicht/Haftmittelschicht (42) umfasst. Produkt nach Anspruch 6, dadurch gekennzeichnet, dass es ferner eine leicht haftende Schicht (46) zwischen der Heißschmelztintenbildempfangsschicht/Haftmittelschicht (42) und der Schutzschicht umfasst, wobei die leicht haftende Schicht aus einem Harz zusammengesetzt ist, das aus der Gruppe bestehend aus Ethylen-Vinylacetat-Copolymerharzen, Acrylharzen, Polyesterharzen und Gemischen dieser Harze ausgewählt ist.
Anspruch[en]
A heat transfer recording medium (50) for recording an image by using hot-melt ink, comprising a support member (41), and a hot-melt ink image receiving layer/adhesive layer (42) formed on said support member (41), characterized in that said hot-melt ink image receiving layer/adhesive layer contains at least first and second resin components, said first resin component having a number-average molecular weight of not less than 16,000 and having a glass transition point of -20°C to 20°C, said second resin component having a number-average molecular weight of not more than 16,000 and a glass transition point of 50°C to 180°C and a weight mixing ratio of said first resin component to said second resin component being 1 : 9 to 5:5. A medium according to claim 1, characterized in that said first resin component has a number-average molecular weight of 16,000 to 30,000 and said second resin component has a number-average molecular weight of 1,500 to 16,000. A medium according to claim 1 or 2, characterized by further comprising an intermediate layer (45), which is one of an easy-adhesion layer and a peeling layer, between said support member (41) and said hot-melt ink image receiving layer/adhesive layer (42), wherein the easy-adhesion layer is composed of a resin selected from the group consisting of ethylene-vinyl acetate copolymer resins, acrylic resins, polyester resins and mixtures of these resins. A medium according to one of claims 1 to 3, characterized in that said hot-melt ink image receiving layer/adhesive layer (42) is made of at least one of a polyester resin and acrylic resin. A printed product (51) comprising a base (44), a hot-melt ink image layer (43), and a hot-melt ink image receiving layer/adhesive layer (42),

characterized in that said hot-melt ink image receiving layer/adhesive layer (42) contains a first resin component and a second resin component as defined in claim 1.
The product according to claim 5, characterized by further comprising a protective layer (45) on said hot-melt ink image receiving layer/adhesive layer (42). The product according to claim 6, characterized by further comprising an easy-adhesion layer (46) between said hot-melt ink image receiving layer/adhesive layer (42) and said protective layer, wherein the easy-adhesion layer is composed of a resin selected from the group consisting of ethylene-vinyl acetate copolymer resins, acrylic resins, polyester resins and mixtures of these resins.
Anspruch[fr]
Matériau d'enregistrement par transfert de chaleur (50) destiné à enregistrer une image en utilisant de l'encre thermofusible, comprenant un organe de support (41) et une couche de réception/couche adhésive d'image en encre thermofusible (42) formée sur ledit organe de support (41), caractérisé en ce que ladite couche de réception/couche adhésive d'image en encre thermofusible contient au moins des premier et second composants de résine, ledit premier composant de résine ayant une masse moléculaire moyenne en nombre de pas moins de 16 000 et ayant un point de transition vitreuse de -20 °C à 20 °C, ledit second composant de résine ayant une masse moléculaire moyenne en nombre de pas plus de 16 000 et un point de transition vitreuse de 50 °C à 180 °C et un rapport de mélange en poids dudit premier composant de résine sur ledit second composant de résine étant de 1 : 9 à 5 : 5. Matériau selon la revendication 1, caractérisé en ce que ledit premier composant de résine a une masse moléculaire moyenne en nombre de 16 000 à 30 000 et ledit second composant de résine a une masse moléculaire moyenne en nombre de 1 500 à 16 000. Matériau selon la revendication 1 ou 2, caractérisé en ce qu'il comprend en outre une couche intermédiaire (45), qui est l'une parmi une couche d'adhérence facile et une couche de pelurage, entre ledit organe de support (41) et ladite couche de réception/couche adhésive d'image en encre thermofusible (42), dans lequel la couche d'adhérence facile est constituée d'une résine choisie dans le groupe constitué par les résines copolymères d'éthylène-acétate de vinyle, les résines acryliques, les résines poly(esters) et les mélanges de ces résines. Matériau selon l'une quelconque des revendications 1 à 3, caractérisé en ce que la couche de réception/couche adhésive d'image en encre thermofusible (42) est constituée d'au moins l'une parmi une résine poly(ester) et une résine acrylique. Produit imprimé (51) comprenant une base (44), une couche d'image en encre thermofusible (43) et une couche de réception/couche adhésive d'image en encre thermofusible (42),

caractérisé en ce que ladite couche de réception/couche adhésive d'image en encre thermofusible (42) contient un composant de résine et un second composant de résine tel que défini dans la revendication 1.
Produit selon la revendication 5, caractérisé en ce qu'il comprend en outre une couche protectrice (45) sur ladite couche de réception/couche adhésive d'image en encre thermofusible (42). Produit selon la revendication 6, caractérisé en ce qu'il comprend en outre une couche d'adhérence facile (46) entre ladite couche de réception/couche adhésive d'image en encre thermofusible (42) et ladite couche protectrice, dans lequel la couche d'adhérence facile est constituée d'une résine choisie dans le groupe constitué par les résines copolymères d'éthylène-acétate de vinyle, les résines acryliques, les résines poly(esters) et les mélanges de ces résines.






IPC
A Täglicher Lebensbedarf
B Arbeitsverfahren; Transportieren
C Chemie; Hüttenwesen
D Textilien; Papier
E Bauwesen; Erdbohren; Bergbau
F Maschinenbau; Beleuchtung; Heizung; Waffen; Sprengen
G Physik
H Elektrotechnik

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