KR20010079785A - Multilayer Adhesively Bonded Articles Having an Ink-Containing Surface Bonded to a Second Surface - Google Patents

Abstract

A laminate comprising at least one ink-containing surface of a polymer substrate adhesively bonded to the surface of a second polymer substrate such that the peel strength between the substrates is at least 6 N / cm. Ink is an electrophotographic ink. In one aspect of the invention, the two substrates are different from each other. In another embodiment of the present invention, the peel strength reaches 6 N / cm within 1 hour after lamination under prescribed conditions.

Description

Multilayer Adhesively Bonded Articles Having an Ink-Containing Surface Bonded to a Second Surface}

The present invention relates to a multilayer stack wherein at least one layer comprises an ink-containing surface.

There has been interest in printing images such as photographs on plastic substrates. The use of liquid toner-based electrophotographic printing for this purpose is particularly desirable because this printing technique produces high quality images.

Once the image is printed on the surface of the plastic substrate, it is necessary to apply a protective film on the printed ink containing surface. The bond strength between the protective film and the printed surface should be sufficiently resistant to delamination under typical conditions of use.

Summary of the Invention

In a first aspect, features of the present invention include (a) a first polymer substrate having a major surface; (b) a second polymer substrate different from the first substrate having a major surface; And (c) an adhesive that bonds the major surface of the first polymer substrate to the major surface of the second polymer substrate such that the peel strength between the polymer substrates is at least 6 N / cm. At least one of the major faces is an ink-containing surface. In addition, both major surfaces of the substrate may be ink-containing surfaces. The two polymer substrates are "different" in that they are made of different base polymers.

The ink is preferably an electrophotographic ink. In some embodiments, the ink comprises a polymer having a Tg (glass transition temperature) of about 30 ° C. or less, and in another embodiment the ink comprises a polymer having a Tg of greater than about 30 ° C.

One example of a suitable ink is derived from the gel organosol-containing liquid toner compositions described, for example, in US Pat. No. 5,652,282 (Baker et al.) And US Pat. No. 5,698,616 (Baker et al.). These toners are (a) a carrier liquid (e.g., an aliphatic hydrocarbon carrier liquid having a Guri-butanol number less than 30) and (b) a thermoplastic (co) that is insoluble in the carrier liquid and has a molecular weight of 50,000 Daltons or more and a polydispersity of less than 15 A (co) polymer conformational stabilizer covalently bound to the polymer core. The core preferably has a Tg of about 30 ° C. or less. The toner may also include a colorant and a charge director. Also suitable are, for example, non-gel organosol-containing liquid toner compositions described in US Pat. No. 5,886,067 to Baker et al.

Another example of a suitable ink is US Pat. No. 4,794,651 (Landa et al.); US 4,842,974 (Landa et al.); US 5,047,306 (Landa et al.); US 5,047,307 (Landa et al.); US 5,192,638 (Landa et al.); US 5,208,130 to Landa et al .; US 5,225,306 (Landa et al.); US 5,264,313 (Landa et al.); US 5,266,435 (Landa et al.); US 5,286,593 (Landa et al.); US 5,346,796 (Landa et al.); US 5,407,771 (Landa et al.); And the liquid toner described in WO 92/17823 (Landa, published October 15, 1992, title “Polymer Blends”).

The compositions are also useful as inks such as ink jet inks and lithographic inks. These inks may be used alone or in combination with each other. For example, the ink-containing surface may include an electrophotographic printed area having electrophotographic ink features and an offset printed area having flat printing ink features. Preferably, however, all printed areas of the laminate are electrophotographic printed areas that have the characteristics of electrophotographic inks.

The adhesive is preferably inserted between the major surfaces of the first and second polymer substrates and at about a nip pressure of about 0.1 to 0.8 MPa (about 15 to 110 lbs / in ² ) and a temperature of about 65 to 150 ° C. Using a linear speed of 0.5 to 25.4 cm / sec (about 0.2 to 10 inches / sec), they are laminated together between a pair of lamination rollers to obtain a peel strength of 6 N / cm or more in a period of about 1 hour or less after lamination. And an adhesive composition that bonds the first and second polymer substrates together.

Multiple polymer substrates can be used. In one preferred embodiment, the first polymer substrate comprises a rigid core layer and the second polymer substrate comprises a flexible overlay film. Preferably, the one or more substrates are substantially transparent, such that an image printed on the ink-containing substrate surface can be seen.

Examples of suitable polymer substrates are selected from the group consisting of polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, polyesters, polyolefins, polycarbonates, and combinations thereof. Also suitable are commercially available from PPG (Pittsburgh, Pa.) Under the trade mark of pore substrates such as TESLIN film. One preferred structure includes a polyvinyl chloride substrate adhesively bonded to a substantially transparent polyester overlay film.

The article may comprise two or more substrates. For example, the article may include a core substrate having a pair of opposing major surfaces, each bonded to a separate overlay film. Such a structure is particularly useful for articles having images printed on two different surfaces.

In a second aspect, features of the present invention include (a) a first polymer substrate having a major surface; (b) a second polymer substrate having a major surface; And (c) between the major surfaces of the first and second polymer substrates, which join the major surface of the first polymer substrate and the major surface of the second polymer substrate such that the peel strength between the polymer substrates is at least 6 N / cm, and about 65 A pair using a line speed of about 0.5 to 25.4 cm / sec (about 0.2 to 10 inches / second) at a temperature of from about 150 ° C. and a nip pressure of about 0.1 to 0.8 MPa (about 15 to 110 lbs / in ² ) And an adhesive selected from adhesive compositions that are laminated together between the lamination rollers of to bond the first and second polymer substrates together to yield a peel strength of at least 6 N / cm within a period of about 1 hour or less after lamination. One or both of the major faces have an ink-containing surface.

The polymer substrates may be the same or different from each other. Useful polymer substrates include those described above in connection with the first aspect of the invention. The article may also include two or more substrates. For example, the article may comprise a core substrate having a pair of opposing major surfaces, each bonded to a separate overlay film. The structure is particularly useful for articles having images printed on two different surfaces.

In a third aspect, features of the present invention are characterized by from about 0.5 to 25.4 cm / sec (about 0.2 to about 150 to about 65 to 150 ° C.) and a nip pressure of about 11 to about 77 kg / cm 2 (about 15 to 110 lbs / in ² ) 10 inch / sec), using a line velocity to laminate the major surfaces of the first and second substrates together via an adhesive, resulting in a peel strength between the first and second substrates of 6 N / cm or more in a period of about 1 hour or less after lamination. Lamination method for the production of the above described article to obtain.

Ink-containing images are preferably

(Iii) charging the surface of the electrophotographic photoreceptor;

(Ii) imagewise exposing the charged surface of the photoreceptor to disperse the charge in the selected area to form a latent image on the photoreceptor surface;

(Iii) contacting the latent image and the toner to form a toned image;

(Iii) It is formed according to an electrophotographic method comprising transferring the rendered image to the main surface of the first polymer substrate.

The toner is preferably a liquid toner. Preferred liquid toners also include film-forming polymers. In some embodiments, the film-forming polymer has a Tg of about 30 ° C. or less, and in other embodiments, the film-forming polymer has a Tg of greater than 30 ° C. After lamination, the article can perform a number of manipulations, such as slitting, cutting, drilling and drilling, foil stamping, weaving and grommeting, foil stamping, perforating, grounding, surface texturing, and the like.

Other features and advantages of the invention will be apparent from the following description of the preferred embodiments and from the claims.

The present invention is now further described by the following examples.

The black, positive, film-forming, electrophotographic inks used in the examples were prepared at a ratio of organosol / pigment 6 according to the method described in Example 40 of US Pat. No. 5,652,282, modified as follows.

Gel organosol prepared according to the method of Example 22 of US 5,652,282 was mixed using a Silverson mixer (Model L2R, Silverson Machine) operated at the lowest speed setting. After mixing for 5 minutes, 1912 g of organosol homogenized to 16.14% (w / w) solids in NORPAR 12 were added in a 4.0 L polyethylene vessel, 1031 g of NORPAR 12 (Exon Chemical, Houston, TX), MONARCH 51 g of 120 carbon black (Cabot Corporation, Billerica, Mass.) And 6.08 g of zirconium HEX-CEM (OMG Chemical Company, Cleveland, Ohio). The mixture was then placed into 10 vertical bead mills (Model 6TGS-1 / 4, Imex, Tokyo, Japan) each having a capacity of 0.5 L. Potter glass beads of 1.3 mm diameter (Porter Industries, NJ, USA) on each mill. 390 g of Parsippany and 300 g of millbase were milled by injection. Each mill was operated for 1.5 hours at 2,000 rpm without cooling water circulating through the cooling jacket of the milling vessel.

A portion of the 12% solids (w / w) toner concentrate thus formed was diluted to approximately 3% (w / w). The diluted toner sample was measured using the test method described in US Pat. No. 5,652,282 and exhibited the following properties:

Number average particle size 0.261 micron

Bulk Conductivity 149 PicoMhos / cm

Free phase conductivity (%) 5%

Dynamic Mobility 0.0402 micron-cm / [volts-second]

This 3% toner was tested on a toner surface coating apparatus described in US Pat. No. 5,652,282. Reflective optical density (ROD) was greater than 1.47 at coating voltages greater than 400 volts.

Example 1

Adhesive-coated polyester film was prepared using a Desmocoll 8634 polyurethane resin solution (15 wt% in methyl ethyl ketone, available from Bayer Chemicals) Mellinex 454 polyester film (23.4 μm (0.92 mil) available from DuPont) The solution was prepared by solution coating onto a wet coating application rate of approximately 375 g / m 2 and drying to obtain an adhesive-coated film. The dry thickness of the adhesive layer was 25.4 μm (1.0 mil).

The adhesive portion of the film was area-printed at a net optical density of 1.6 using a liquid toner base, black, positive type, film-forming, electrophotographic ink (prepared as described above). The net optical density is equal to the white light optical density-white light optical density of the unprinted film, measured in reflectance mode using a Macbeth photo densitometer. The net optical density corresponded to an ink net optical density of 1.3 for paper substrates printed under the same conditions.

After printing, the adhesive-coated film was laminated to a white polyvinyl chloride substrate. Lamination was carried out at a rate of 1.0 cm / sec (0.4 inch / sec) between two heating rollers (roll surface temperature = 135-138 ° C.) to obtain laminated and printed articles. The article was cut into 2.5 cm (1 inch) wide strips and the 180 degree peel strength required to cause delamination was measured 15 minutes after the lamination step using an Instron tester (Model 5542). The crosshead speed was 30.5 cm / minute (12 inches / minute). Peel strength was measured at 8.8 N / cm (5.0 lbs / in.).

In a separate experiment, an unprinted adhesive-coated polyester film was laminated to the same white polyvinyl chloride substrate in the same manner. Peel strength was measured at approximately 21 N / cm (12 lbs / in.), As a result of which the polyester film was torn.

Example 2

Methyl ethyl ketone (201 g), Epon 1007F epoxy resin (143 g of 20 wt% solution in methyl ethyl ketone, available from Shell Chemicals), epoxycyclohexylethyl trimethoxy silane (14.4 g, from Aldrich Chemicals) ) And Vestanat T1890E isocyanate (215 g of a 20 wt% solution in methyl ethyl ketone, available from creanova) to 1428 g of Desmocoll 8634 polyurethane resin (15 wt% in methyl ethyl ketone, available from Bayer Chemicals) The same method as in Example 1 was carried out except for using the adhesive coating solution prepared by. The resulting laminate had a peel strength of 7.9 N / cm (4.5 lbs / in.).

Example 3

Adhesive-coated polyester film with Airflex 7200 ethylene vinyl acetate copolymer dispersion (72 wt% in water, available from Air Products Chemicals) Mellinex 454 polyester film (23.4 μm (0.92 mil) available from DuPont) The solution was prepared by solution coating at a wet coating application rate of approximately 75 g / m 2 and drying to obtain an adhesive-coated film. The dry thickness of the adhesive layer was 50.8 μm (2 mil).

The adhesive portion of the film was area-printed with a net optical density of 1.6 using a liquid toner base, black, positive type, film forming, electrophotographic ink (prepared as described above) and white according to the method described in Example 1 It was laminated to a polyvinyl chloride substrate. Peel strength measured as described in Example 1 was measured at 7.9 N / cm (4.5 lbs / in.).

In a separate experiment, an unprinted adhesive film was laminated on the same white polyvinyl chloride substrate in the same way. Peel strength was measured at approximately 8.8 N / cm (5.0 lbs / in.).

Example 4

Bynel E418 anhydrous-modified ethylene vinyl acetate polymer adhesive (127 μm (5.0 mil) thick, DuPont) between the white polyvinyl chloride substrate and the coated side of the sheet of coated polyester film (Mylar 50RL31, available from DuPont Chemical) The sheets of commercially available) were laminated to prepare a laminated structure. Lamination was carried out according to the method described in Example 1. The peel strength of the resulting laminate, measured as described in Example 1, was 10.5 N / cm (6 lbs / in.).

As a separate experiment, the adhesion of Bynel E418 to the electrophotographic ink was tested. Substrates were prepared by forming a primer layer and then forming a subbing layer on a 101.6 μm (4 mil) thick polyvinylidene chloride primed polyester film (commercially available from 3M Company). Primer layer is 250 ppm by weight of colloidal vanadium oxide (added as 1% dispersion in water, available from 3M Company), hydrolyzed glycidoxypropyl trimethoxysilane (18 hours prior to addition to primer layer coating solution) 2500 wt ppm of 5% hydrolyzed in water using 50 ppm HCl as catalyst, 500 wtpp of Triton X-100 surfactant (available from Rohm & Haas), and Eastek 2400 polymer (40% from Eastman Chemical) Prepared by coating (12.5 micron wet thickness) and drying an aqueous dispersion containing 2.5% by weight of a commercially available dispersion. The serving layer was prepared by coating (9 micron wet thickness) and drying the coating solution of Example 1A of US Pat. No. 5,204,219 on the primer layer.

The serving layer of the resulting film was area-printed at an optical density of 1.2 using a liquid toner base, black, positive type, film-forming, electrophotographic ink (prepared as described above). The adhesion of the Bynel E418 adhesive to the ink was achieved by laminating a 127 μm (5.0 mil) thick adhesive sheet between the coated surface of the Mylar 50RL31 film and the printed surface of the serving layer of the polyester film according to the method described in Example 1. Was measured.

Peel strength of the resulting laminate was measured in accordance with the method described in Example 1. Separation between Bynel E418 and the print surface occurred at a peel strength of 6.1 N / cm (3.5 lbs / in.). Separation of the Bynel E418 adhesive from the Mylar 50RL31 film did not occur in the peel test.

Example 5

The method of Example 4 was carried out except that Bynel 11E554 film (commercially available from DuPont Chemical, described as modified ethylene vinyl acetate) was used instead of Bynel E418. Peeling of the adhesive from pure polyvinyl chloride showed a peel strength of 8.8 N / cm (5 lbs / in.). Peeling of the adhesive from the electrophotographic ink showed a peel strength of 10 N / cm (6 lbs / in.). Separation of the Bynel 11E554 adhesive from the Mylar 50RL31 film did not occur in the peel test.

Example 6

Irgacure 1700 photoinitiator (3 g, available from Ciba-Geigy), 15 wt% solution of 2-isocyanato ethyl methacrylate-modified polyacrylic acid photopolymer in Dowanol PM (Dow Chemical) (240 g, PCT publication The coating solution was prepared by adding to the method described in PCT / US96 / 03542) and Sartomer SR 259 polyethylene glycol diacrylate (21.0 g of pure liquid, available from Sartomer) to 104.5 g of Dowanol PM. The solution is then knife-coated on a polyethylene naphthalate film (commercially available from Daijin Film Co.) at a wet coating application rate of approximately 200 g / m 2 and dried at 80 ° C. for 3 minutes to give an uv-curable adhesive-coated film Obtained. The dry thickness of the adhesive layer was 25.4 μm (1.0 mil).

The adhesive portion of the film was area-printed using a liquid toner-based, black, positive type, film-forming, electrophotographic ink (prepared as described above) at a pure optical density of 1.6, and then the method described in Example 1 On a white polyvinyl chloride substrate.

After lamination, the adhesive was cured by exposing the printed and laminated articles to UV light in air (40 unit exposure using the Burges Control Control Exposure Unit, available from Bugis Industries, Minneapolis, Minnesota, USA). The article was then cut into strips 2.5 inches (1 inch) wide. The adhesive tape (396 adhesive tape, available from 3M) was applied to the exposed polyethylene naphthalate surface of the article to provide the 180 degree peel strength required to cause delamination of the polyethylene naphthalate film from the polyvinyl chloride substrate. It was measured according to the method. Peel strength was measured to be greater than 6.1 N / cm (3.5 lbs / in.).

In a separate experiment, an unprinted adhesive film was laminated to the same white polyvinyl chloride substrate in the same manner and the peel strength was measured. Peel strength was high enough to tear the polyethylene naphthalate film.

Example 7

Adhesive-coated polyethylene naphthalate films were prepared according to the method of Example 6 except that Sartomer SR610 polyethylene glycol diacrylate was used instead of Sartomer SR259 polyethylene glycol diacrylate. The dry thickness of the adhesive layer was 25.4 μm (1.0 mil). The film was then used to produce the laminated article described in Example 1 except that the temperature of the heating roller used for lamination was 95 to 120 ° C. The resulting article had a peel strength of greater than 6.1 lbs / in.

In a separate experiment, an unprinted adhesive film was laminated to the same white polyvinyl chloride substrate in the same manner and the peel strength was measured. Peel strength was high enough to tear the polyethylene naphthalate film.

Example 8

The method of Example 7 was followed except that the adhesive was coated onto a polyethylene terephthalate film (25.4 μm (1 mil) thick E2Q film available from Daijin Film). Instead of Sartomer SR610 polyethylene glycol diacrylate, Sartomer CN 966 A80, a urethane acrylate in combination with tripropylene glycol diacrylate, was used. The 180 degree peel strength required to cause delamination was measured to be greater than 3.5 lbs / in. (6.1 N / cm).

In a separate experiment, an unprinted adhesive film was laminated to the same white polyvinyl chloride substrate in the same way and the peel strength was measured. Peel strength was high enough to tear the polyethylene terephthalate film.

Example 9

The method of Example 4 was followed except that a polyester film (amorphous, thermoplastic, high molecular weight, linear, saturated, polyester resin) coated with Bostik Vitel 3554 adhesive was used instead of Bynel E418. The adhesive-coated film was solution coated with a 40% solids solution of Bostik Vitel 3554 polyester adhesive to a Mellinex 454 polyester film (23.4 μm (0.92 mil), available from DuPont) at a wet coating coverage of 125 g / m 2, It was prepared by drying to obtain an adhesive-coated film. The dry thickness of the adhesive layer was 50.8 μm (2.0 mil). Lamination on a white polyvinyl chloride substrate yielded an article having a peel strength of greater than 18 N / cm (10 lbs / in.).

In a separate experiment, the adhesion of the Bostik Vitel 3554 to the electrophotographic ink was tested according to the method of Example 4. Peeling of the adhesive-coated polyester film from the electrophotographic ink showed a peel strength of 7.1 N / cm (4 lbs / in.).

Example 10

The method of Example 4 was followed except that a polyester film coated with a mixture of Desmocoll 8634 semicrystalline polyurethane resin solution (Biel Chemical) and Bostik Vitel 3554 amorphous polyester resin was used instead of Bynel E418. Adhesive-coated films were 7.5% solids Desmocoll 8634 and 7.5% solids Bostik Vitel 3554 40% on Mellinex 454 polyester film (23.4 μm (0.92 mil), available from DuPont) with a wet coating coverage of approximately 170 g / m 2. It was prepared by solution coating with a solution containing a mixture of and drying to obtain an adhesive-coated film. The dry thickness of the adhesive layer was 25.4 μm (1.0 mil). Lamination on a white polyvinyl chloride substrate yielded an article having a peel strength of greater than 18 N / cm (10 lbs / in.).

In a separate experiment, the adhesion of the Desmocoll 8634 / Bostik Vitel 3554 mixture to the electrophotographic ink was tested according to the method of Example 4. Peeling of the adhesive-coated polyester film from the electrophotographic ink showed a peel strength of 7.1 N / cm (4 lbs / in.).

The laminate was also peeled off at 90 degrees, showing a weak peel at a peel strength of 4.4 N / cm (2.5 lbs / in.) Compared to the zippered peel observed in the laminate structure with Desmocoll 8634 adhesive only. The adhesive-coated film had a surface that was hard and non-tacky compared to the tacky surface observed in the adhesive composition containing Bostik 3554 only.

Example 11

The method of Example 4 was followed except that a polyester film coated with a two layer adhesive composition was used instead of Bynel E418. The adhesive-coated film was airflex 7200 ethylene-vinyl acetate copolymer dispersion (Air Products Chemicals) on Mellinex 454 polyester film (23.4 μm (0.92 mil), available from DuPont) with a wet coating application rate of approximately 40 g / m 2. Prepared by solution coating and drying with 6.5% solids aqueous dispersion of g) to obtain an adhesive-coated film having a dry thickness of 25.4 μm (1.0 mil). The other adhesive layer was then obtained by solution coating a 15% solids solution of Desmocoll 8634 on the top of the Airflex 7200 layer at a wet coating application rate of 85 g / m 2 and drying to obtain a layer having a dry thickness of 12.7 μm (0.5 mil). Was added. The overall thickness of the resulting two layer adhesive was 38.1 μm (1.5 mil). Lamination on a white polyvinyl chloride substrate yielded an article with a peel strength of 11 N / cm (7 lbs / in.).

In a separate experiment, the adhesion of the two-layer adhesive to the electrophotographic ink was tested according to the method of Example 4 except that the net optical density of the area-printed adhesive film was 1.6. Peeling from the electrophotographic ink of the adhesive coated polyester film showed a peel strength of 8.5 N / cm (4.8 lbs / in.).

The laminate was also peeled at 90 degrees, showing a weak peel at a peel strength of 4.4 N / cm (6.7 lbs / in.) As compared to the zippered peel observed in the laminate structure with Desmocoll 8634 adhesive only. The adhesive-coated film had a hard and non-tacky surface compared to the tacky surface observed in the adhesive composition containing only Bostik 3554.

Example 12

The method of Example 1 was followed except that Desmocoll 530 polyester-based polyurethane was used instead of Desmocoll 8634 and the thickness of the polyester film was 76.2 μm (3 mil). In addition, the lamination rate was 1.3 cm / sec (0.5 inch / sec). The resulting article exhibited a peel strength of 7.0 N / cm (4.0 lbs / in.) As measured in Example 1.

In a separate experiment, an unprinted adhesive-coated polyester film was laminated to the same white polyvinyl chloride substrate in the same manner. The resulting article was stored at 60 ° C. and 100% relative humidity for 2 weeks before peel strength was measured to be less than 5.3 N / cm (3 lbs / in.).

Example 13

The method of Example 12 was followed except that the adhesive was prepared by combining 15 parts of Desmocoll 530, 85 parts of methyl ethyl ketone, 3 parts of Vestanat T1890E isocyanate and 1 part of ethoxycyclohexylethyl trimethoxy silane. The resulting article exhibited a peel strength of 7.0 N / cm (4.0 lbs / in.) As measured in Example 1. There is a failure mode between the adhesive and the ink.

In a separate experiment, an unprinted adhesive-coated polyester film was laminated to the same white polyvinyl chloride substrate in the same manner. The resulting article was stored at 60 ° C. and 100% relative humidity for 2 weeks and then peel strength was measured to be 17.6 N / cm (10 lbs / in.).

Example 14

The method of Example 12 was prepared except that the adhesive was prepared by combining 15 parts of Desmocoll 530, 85 parts of methyl ethyl ketone, 3 parts of Vestanat T1890E isocyanate, 1 part of epoxycyclohexylethyl trimethoxy silane, and 2 parts of Epon 1007F epoxy resin. Was performed. The resulting article exhibited a peel strength of 7.0 N / cm (4.0 lbs / in.) As measured in Example 1. The failure mode was separation of ink.

In a separate experiment, an unprinted adhesive-coated polyester film was laminated to the same white polyvinyl chloride substrate in the same manner. The resulting article was stored at 60 ° C. and 100% relative humidity for 2 weeks and then peel strength was measured to be 17.6 N / cm (10 lbs / in.).

Example 15

The method of Example 3 was carried out except that the polyester film was coated with a mixture of Desmocoll 8634 polyurethane resin solution (Biel Chemical) and Airflex 7200 ethylene-vinyl acetate copolymer dispersion (Air Products Chemicals). The adhesive-coated film comprises a mixture of approximately 1 part 15 wt% Desmocoll 8634 and one part 15 wt% ethylene-vinyl acetate copolymer (prepared by mixing 625 g Airflex 7200 dispersion and 2375 g methyl ethyl ketone) in methyl ethyl ketone. Prepared by solution coating and drying on a Mellinex 454 polyester film (23.4 μm (0.92 mil), available from DuPont) at a wet coating application rate of g / m 2 to obtain an adhesive-coated film. The dry thickness of the adhesive layer was 25.4 μm (1.0 mil). The adhesive-coated film had a dry, non-tacky feel.

The adhesive portion of the film was area-printed at a net optical density of 1.6 using a liquid toner base, black, positive type, film-forming, electrophotographic ink (prepared as described above) and according to the method described in Example 1 It was laminated to a white polyvinyl chloride substrate. The peel strength measured as described in Example 1 except that measured 5 minutes after lamination was 8.1 N / cm (4.6 lbs / in.).

Another sample identical to the first sample was placed in a Thermotron environmental container for 14 days after lamination. The vessel was kept at 60 ° C. and 95% relative humidity. At the end of day 14, the sample was taken out and stored in the desiccator at room temperature for another 14 days. Subsequently, peel strength was measured as described in Example 1, whereupon it was measured at 10.2 N / cm (5.8 lbs / in.).

In a separate experiment, an unprinted adhesive-coated polyester film was laminated to the same polyvinyl chloride substrate in the same manner. Peel strength measured after 5 minutes of lamination was 15 N / cm (8.6 lbs / in.). Two additional laminated samples were stored as described above for 14 days at high humidity and high temperature (60 ° C./95% relative humidity). Five minutes after removal from the Thermotron vessel, the peel strength of one of the samples was measured to be 9.5 N / cm (5.4 lbs / in.). The other sample was placed in the desiccator for 14 days at room temperature. After removal from the desiccator, the peel strength was measured to be 9.0 N / cm (5.1 lbs / in.).

In another experiment, the unprinted adhesive-coated film was left at 40 ° C. for one week. It was then laminated on the same white polyvinyl chloride substrate in the same way. Peel strength measured after 5 minutes of lamination was 19 N / cm (10.6 lbs / in.).

Example 16

The adhesive coating solution was prepared by combining 1 part of 15 wt% ethylene-vinyl acetate solution and 2 parts of 15 wt% solution of Q-Thane QA3781 polyurethane resin (available from K. J. Queen, Seabrook, NH). The same method as in Example 15 was carried out except that.

The adhesive-coated film was zone-printed in the same manner as in Example 15 and laminated on a white polyvinyl chloride substrate. The peel strength of the laminate, measured 5 minutes after lamination, was 9.9 N / cm (5.6 lbs / in.). The peel strength of the same laminate was measured for 14 days at high humidity and high temperature (60 ° C./95% relative humidity), and after drying for 14 days at room temperature, measuring 14.3 N / cm (8.1 lbs / in.) It was.

The peel strength of the laminate prepared by laminating the unprinted adhesive-coated film and the same white polyvinyl chloride substrate as described in Example 15 was 9.9 N / cm (5.6 lbs / in.). Two further laminated samples were left for 14 days as described above at high humidity and high temperature (60 ° C./95% relative humidity). Five minutes after removal from the Thermotron vessel, the 180 degree peel strength of one of the samples was measured at 9.5 N / cm (5.3 lbs / in.). Another sample was placed in the desiccator for 14 days at room temperature. After taking out from the desiccator, the peeling strength was measured and found to be 15 N / cm (8.5 lbs / in.).

In another experiment, the unprinted adhesive-coated film was left at 40 ° C. for one week. It was then laminated on the same white polyvinyl chloride substrate in the same way. The peel strength measured after 5 minutes of lamination was 13.2 N / cm (7.5 lbs / in.).

Example 17

The adhesive coating solution was prepared with 1 part of 15 wt% ethylene-vinyl acetate solution, 2 parts of 15 wt% solution of Q-Thane QA3781 polyurethane resin and 15 wt% amorphous polyester resin (Vitel B3554, Bostick, Middleton, Mass.) ) The same method as in Example 15 was carried out except that 1 part was prepared by combining.

The adhesive coated film was zone-printed in the same manner as in Example 15 and laminated on a white polyvinyl chloride substrate. The peel strength of the laminate measured after 5 minutes of lamination was 10.4 N / cm (5.9 lbs / in.). The peel strength of the same laminate was exposed for 14 days at high humidity and high temperature (60 ° C./95% relative humidity), dried at room temperature for 14 days and measured to be 13.8 N / cm (7.8 lbs / in.). .

The peel strength of the laminate prepared by laminating the unprinted adhesive-coated film and the same white polyvinyl chloride substrate as described in Example 15 was measured at 11.6 N / cm (6.6 lbs / in.). Two further laminated samples were left for 14 days as described above at high humidity and high temperature (60 ° C./95% relative humidity). The 180 degree peel strength of one of the samples measured 5 minutes after removal from the Thermotron vessel was 10.2 N / cm (5.8 lbs / in.). The other sample was placed in the desiccator for 14 days at room temperature. After removal from the desiccator, the peel strength thereof was measured and found to be 12 N / cm (6.8 lbs / in.).

In a separate experiment, the unprinted adhesive-coated film was placed at 40 ° C. for one week. It was then laminated on the same white polyvinyl chloride substrate in the same way. Peel strength measured after 5 minutes of lamination was 9.5 N / cm (5.4 lbs / in.).

Other embodiments are within the scope of the following claims.

Claims (10)

(a) a first polymer substrate having a major surface; (b) a second polymer substrate different from the first substrate having a major surface, wherein the major surfaces comprise ink-containing images; And (c) an article comprising an adhesive for bonding the main surface of the first polymer substrate to the main surface of the second polymer substrate such that the peel strength between the polymer substrates is at least 6 N / cm. The article of claim 1, wherein the first polymer substrate comprises a rigid core layer and the second polymer substrate comprises a flexible overlay film. The article of claim 1, wherein the polymeric substrate is substantially transparent. The article of claim 1, wherein the polymer substrate is selected from the group consisting of polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, polyesters, polyolefins, polycarbonates, and combinations thereof. . The article of claim 1, wherein the first polymer substrate comprises polyvinyl chloride and the second polymer substrate comprises polyester. 6. The article of claim 1, wherein one of the polymeric substrates comprises a porous film. 7. The adhesive of claim 1, wherein the adhesive is inserted between the major surfaces of the first and second polymer substrates and has a temperature of about 65 to 150 ° C. and about 0.1 to 0.8 MPa (about 15 to 110 lbs / in the nip (nip) pressure in ^2), using a line speed of about 0.5 to 25.4 ㎝ / sec (about 0.2 to about 10 inches / second), it is laminated together between a pair of laminating rollers, and then laminated about an hour An article selected from an adhesive composition to obtain a peel strength of at least 6 N / cm within the following time period. (a) bonding the first polymer substrate having the major surface and the second polymer substrate having the major surface with an adhesive such that the adhesive is in the middle of the major surfaces of the polymer substrates, (b) a linear velocity of about 0.5 to 25.4 cm / sec (about 0.2 to 10 inches / sec) at a temperature of about 65 to 150 ° C. and a nip pressure of about 0.1 to 0.8 MPa (about 15 to 110 lbs / in ² ). And laminating the major surfaces of the first and second substrates via an adhesive to obtain peel strength between the first and second substrates of at least 6 N / cm within a period of about 1 hour or less after lamination. . The method of claim 8, (a) charging the surface of the electrophotographic photoreceptor; (b) imagewise exposing the charged surface of the photoreceptor to disperse the charge in the selected area to form a latent image on the photoreceptor surface; (c) contacting the latent image and the liquid toner to form a toned image; (d) transferring the rendered image to a major surface of the first polymer substrate A method comprising ink-containing image formation according to an electrophotographic imaging process. 10. The method of claim 9, wherein the toner comprises a liquid toner comprising a film-forming polymer.