EP1122086A1

EP1122086A1 - Cover film for protection of a print and method for production thereof

Info

Publication number: EP1122086A1
Application number: EP00300874A
Authority: EP
Inventors: Akio Terai; Noriyuki Kawashima
Original assignee: Fujipla Inc
Current assignee: Fujipla Inc
Priority date: 2000-02-04
Filing date: 2000-02-04
Publication date: 2001-08-08

Abstract

A cover film for protection of a print from the influence of weather, the cover film being produced by coating an aqueous dispersion containing 50 through 500 weight portion of at least one ingredient of a group including ethylene, unsaturated carboxylic acid and unsaturated carboxylic ester, in addition to aliphatic conjugated diolefin monomer and vinyl monomer, 10 through 500 weight portion of a tackifier and 50 through 500 weight portion of a crystalline plasticizer which is liquefied at a temperature of 40°C, on a substrate and a method for the production thereof.

Description

FIELD OF THE INVENTION

This invention relates to a cover film employable for protection of a print and a method for production thereof. More specifically, this invention relates to a cover film to be attached on a print which is printed on a sheet of paper employable for printing conducted by employing a type of a printer which uses a water based ink or which is printed on a sheet of paper on which a film for expediting permeation of a water based ink into the paper and for causing clear printing thereon, is attached, for the purpose to project the print from a potential external hazard particularly caused by rain unavoidable, when the print is kept outdoors.

BACKGROUND OF THE INVENTION

It is well-known that some type of prints such as posters, sign boards, advertising signals et al. are displayed outdoors and are inclined to incur external hazards such as the influence of weather and/or climate including the influence of rain and/or the influence of storm. For the purpose to protect the foregoing prints from such external hazards, a cover film is attached thereon. In other words, a cover film resistive against the influence of weather and/or climate is attached on the prints to be displayed outdoors. On the other hand, it is known that the paper employable for printing conducted by employing a printer which employs a type of water based ink, is required to be coated with a film for expediting permeation of the water based ink into the paper and for causing clear printing thereon. The film available in the prior art for expediting permeation of the water based ink into the paper and for causing clear printing thereon is a film of a hydrophilic material such as polyvinyl alcohol, water soluble acrylic resin, water soluble polyester resin, aqueous urethane resin, gelatin, polyethylene oxide or the like.
A typical film resistive against the influence of weather and/or climate and which is available in the prior art is a film of polyethylene terephthalate or oriented polypropylene which is coated a film of polyethylene resin, ethylene vinyl acetate copolymer resin, ethylene acrylic ester copolymer resin, ethylene methacrylic ester copolymer resin, ethylene acrylate copolymer resin, ethylene methacrylate copolymer resin, ethylene acrylate acrylic ester copolymer resin, ethylene methacrylate acrylic ester copolymer resin, ethylene acrylate methacrylic ester copolymer resin, ethylene acrylate methacrylic ester copolymer resin or ethylene methacrylate methacrylic ester copolymer resin.
The foregoing cover film available in the prior art is, however, involved with the following drawbacks. Firstly, the cover film is inclined to be readily removed from the print which is produced by printing conducted on a sheet of paper which is coated with the foregoing film for expediting permeation of a water based ink into the paper and for causing clear printing thereon and which actually is made of a hydrophilic material, in a rather long period in which the print is kept outdoors. Secondly, the process to cover the print with the cover film must be conducted at a relatively high temperature for example 100° C.

SUMMARY OF THE INVENTION

The first object of this invention is to provide a cover film employable for protection of a print which is printed on a sheet of paper employable for printing conducted by employing a type of a printer which uses a water based ink or which is printed on a sheet of paper on which a film for expediting permeation of a water based ink into the paper and for causing clear printing thereon is attached, for the purpose to protect the print from a potential external hazard particularly caused by rain unavoidable, when the print is kept outdoors, wherein the effects of the protection is durable for a long time and the cover film can be attached on a print at a relatively low temperature.
The second object of this invention is to provide a method for producing the foregoing cover film.
This invention is based on a concept to utilize the chemical property that a cover film produced by coating an aqueous dispersion containing 100 weight portion of a copolymer latex containing at least one ingredient of a group including ethylene, unsaturated carboxylic acid and unsaturated carboxylic ester, in addition to aliphatic conjugated diolefin monomer and vinyl monomer, 10 through 200 weight portion of a tackifier and 50 through 500 weight portion of a crystalline plasticizer, is effective to adhere the cover film itself to the film of a hydrophilic material such as polyvinyl alcohol, water soluble acrylic resin, water soluble polyester resin, aqueous urethane resin, gelatin, polyethylene oxide or the like, when the cover film is pressed toward the film of the hydrophilic material under a high temperature, because the copolymer latex, the tackifier and the crystalline plasticizer are melted together under a high temperature and the crystalline plasticizer plasticizes the copolymer latex and the tackifier, resultantly reducing the inter molecular bonding strength and causing them to become adhesive to one another.
More specifically, a cover film in accordance with this invention is a film produced by coating an aqueous dispersion containing 50 through 500 weight portion of at least one ingredient of a group including ethylene, unsaturated carboxylic acid and unsaturated carboxylic ester, in addition to aliphatic conjugated diolefin monomer and vinyl monomer, 10 through 500 weight portion of a tackifier and 50 through 500 weight portion of a crystalline plasticizer which is liquefied at a temperature of 40° C, on a substrate which actually is a single layer film or a plural layer film of polyethylene terephthalate or oriented polypropylene or on a substrate which actually is a single layer film or a plural layer film of polyethylene terephthalate or oriented polypropylene which is coated with a film of polyethylene resin, ethylene vinyl acetate copolymer resin, ethylene acrylic ester copolymer resin, ethylene methacrylic ester copolymer resin, ethylene acrylate copolymer resin, ethylene methacrylate copolymer resin, ethylene acrylate acrylic ester copolymer resin, ethylene methacrylate acrylic ester resin, ethylene acrylate methacrylic ester copolymer resin or ethylene methacrylate methacrylic ester copolymer resin.
Incidentally, a method for producing a cover film in accordance with this invention is a step for coating an aqueous dispersion containing 50 through 500 weight portion of at least one ingredient of a group including ethylene, unsaturated carboxylic acid and unsaturated carboxylic ester, in addition to aliphatic conjugated diolefin monomer and vinyl monomer, 10 through 500 weight portion of a tackifier and 50 through 500 weight portion of a crystalline plasticizer which is liquefied at a temperature of 40° C, on a substrate which actually is a single layer film or a plural layer film of polyethylene terephthalate or oriented polypropylene or on a substrate which actually is a single layer film or a plural layer film of polyethylene terephthalate or oriented polypropylene which is coated with a film of polyethylene resin, ethylene vinyl acetate copolymer resin, ethylene acrylic ester copolymer resin, ethylene methacrylic ester copolymer resin, ethylene acrylate copolymer resin, ethylene methacrylate copolymer resin, ethylene acrylate acrylic ester copolymer resin, ethylene methacrylate acrylic ester resin, ethylene acrylate methacrylic ester copolymer resin or ethylene methacrylate methacrylic ester copolymer resin, the coating step being conducted by employing a gravure coater, roll coater, bar coater or the like, at a temperature of 40 ° C or less.
The followings supplement the foregoing description for the aqueous dispersion.
1. A polymer derived from 4 through 25 weight % of aliphatic conjugated diolefin monomer, 1 through 15 weight % of unsaturated carboxylic acid and 60 through 95 weight % of vinyl monomer shows a good grade of adhesion and a good film quality.
2. Butadiene, isoprene, chloroprene and 1, 3-pentadiene can be employed as the foregoing aliphatic conjugated diolefin monomer. Out of the above three ingredients, butadiene is the best.
3. From the viewpoints of blocking, a relative portion of a less than 25 weight % is preferable for aliphatic conjugated diolefin monomer. The relative portion of aliphatic conjugated diolefin monomer must be in a range of 4 through 25 weight %, more preferably in a range of 10 through 25 weight %, because the adhesion is not satisfactory under a high temperature for aliphatic conjugated diolefin monomer in a relative portion of a less than 4 weight %.
4. The foregoing unsaturated carboxylic acid includes acrylic acid, methacrylic acid, fumaric acid, malefic acid, malefic anhydride and itaconic acid. The relative portion thereof must be in a range of 1 through 15 weight %. If the relative portion is less than 1 weight %, the blocking property is not satisfactory. If the relative portion is more than 15 weight %, the anti-water property is extremely bad.
5. The foregoing vinyl monomer includes aromatic vinyl compounds such as styrene, α-methylstyrene, vinyl toluene et al., alkyl ester methacrylates such as methyl methacrylate, ethyl methacrylate, butyl methacrylate et al., alkyl ester acrylate such as ethyl acrylate, butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate et al., vinyl cyanide compounds such as acrylonitrile, methacrylnitrile et al., vinyl ester compounds such as vinyl acetate et al. and various functionality monomers such as acrylamide, methacrylamide, glycidyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, sodium styrene sulfonate, N-methylol acrylamide, N-butoxymethyl acrylamide, acrylamide methylpropan sulfonate, diethyl aminoethyl methacrylate et al. The foregoing vinyl monomers are employed in a relative portion range of 60 through 95 weight % for the purpose to increase cohesion of the polymer. The relative portion is essential to obtain a good grade of adhesion and the anti-blocking property. Out of the foregoing vinyl monomers, styrene is the best, followed by methyl methacrylate and acrylonitrile.
Any tackifier available in the prior art can be employed for the foregoing purpose. It is needless to emphasize that the compatibility is good with the base resin. Rosin, the derivatives of rosin, terpene and the derivatives of terpene are preferable.
Typical examples of the foregoing crystalline plasticizers are dicyclohexyl phthalate, diphenyl phthalate, dihexyl phthalate, dihydro aviethyl phthalate, dimethyl isophthalate, sucrose benzoate, ethyleneglycol dibenzoate, trimethylolethane tri-benzoate, glyceride tri-benzoate, pentaerythritol tetra-benzoate, sucrose octacetate, tri-cyclohexyl citrate and N-cyclohexyl p-toluenesulfonamide et al.

BRIEF DESCRIPTION OF THE DRAWING

This invention, together with its various features and advantages, can be readily understood from the following more detailed description presented in conjunction with following drawing, in which :
Fig. 1 is a schematic drawing illustrating a process for attaching a cover film in accordance with one embodiment of this invention on the both surfaces of a print to be protected by the cover film of this invention.

DETAILED DESCRIPTION OF THIS INVENTION

A detailed description will be presented below for a cover film in accordance with 14 embodiments of this invention and for a method for employing a cover film in accordance with this invention.

FIRST EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 60 weight portion of a tackifier which actually is rosin estyer and 160 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate. In this manner, a cover film in accordance with the first embodiment of this invention is produced.

SECOND EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 60 weight portion of a tackifier which actually is rosin estyer and 160 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the second embodiment of this invention is produced.

THIRD EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 60 weight portion of a tackifier which actually is terpene and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate. In this manner, a cover film in accordance with the third embodiment of this invention is produced.

FOURTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 60 weight portion of a tackifier which actually is terpene and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the fourth embodiment of this invention is produced.

FIFTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 60 weight portion of a tackifier which actually is terpene and 160 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate. In this manner, a cover film in accordance with the fifth embodiment of this invention is produced.

SIXTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 60 weight portion of a tackifier which actually is terpene and 160 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the sixth embodiment of this invention is produced.

SEVENTH EMBODIMENT

An aqueous dispersion is produced by dispersing dicyclohexyl phthalate in water at a temperature less than 50° C. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer.. In this manner, a cover film in accordance with the seventh embodiment of this invention is produced.

EIGHTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 100 weight portion of a tackifier which actually is rosin estyer and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the eighth embodiment of this invention is produced.

NINTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 60 weight portion of a tackifier which actually is rosin estyer and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the ninth embodiment of this invention is produced.

TENTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 100 weight portion of the foregoing copolymer, 2 weight portion of a tackifier which actually is rosin estyer and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the tenth embodiment of this invention is produced.

ELEVENTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 50 weight portion of the foregoing copolymer, 100 weight portion of a tackifier which actually is rosin estyer and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the eleventh embodiment of this invention is produced.

TWELFTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 10 weight portion of the foregoing copolymer, 100 weight portion of a tackifier which actually is rosin estyer and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the twelfth embodiment of this invention is produced.

THIRTEENTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 10 weight portion of the foregoing copolymer, 100 weight portion of a tackifier which actually is terpene and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the thirteenth embodiment of this invention is produced.

FOURTHTEENTH EMBODIMENT

An emulsion polymerization process is employed to polymerize 10 weight % of butadiene, 10 weight % of methacrylic acid and 80 weight % of styrene to produce styrene butadiene methacrylate copolymer particles containing the styrene component, butadiene component and methacrylic acid componet in a ratio of 80 : 10 : 10. An aqueous dispersion containing 10 weight portion of the foregoing copolymer, 100 weight portion of a tackifier which actually is terpene phenol copolymer and 100 weight portion of crystalline plasticizer which actually is dicyclohexyl phthalate (for example, an aqueous dispersion containing dicyclohexyl phthalate, a surface active agent and a water soluble resin in a ratio of 100 : 3 : 3) is produced. A gravure coater is employed to coat the foregoing aqueous dispersion on a substrate of polyethylene terephthalate coated with ethylene vinyl acetate copolymer. In this manner, a cover film in accordance with the fourteenth embodiment of this invention is produced.

METHOD FOR EMPLOYING A COVER FILM OF THIS INVENTION

Referring to Fig. 1, letters and/or pictures (7) are printed on a film for expediting permeation of the water based ink into the paper and for causing clear printing thereon (2) coated on one surface of a sheet of paper (1) to produce a print (3). The film for expediting permeation of the water based ink into the paper and for causing clear printing thereon (2) is a film of a hydrophilic material such as polyvinyl alcohol, water soluble acrylic resin, water soluble polyester resin, aqueous urethane resin, gelatin, polyethylene oxide or the like. Two sheets of cover films (4) in accordance with the first through fourteenth embodiments of this invention are attached on the both surfaces of the print (3) at a low temperature of approximately 80° C. As a result, a film (6) of plasticized mixture of the foregoing copolymer latex, the tackifier and the crystalline plasticizer which film is attached on the surface of the substrate (5) of polyethylene terephthalate or ethylene vinyl acetate, is allowed to contact the surfaces of the print (3).

Tests for adhesion between the film and the print, the strength of the film and the anti-water property were conducted to each of the foregoing prints each of which was attached with the cover film of this invention. Results of the tests are indicated in a table presented below.

RESULTS OF THE TESTS
EMBODIMENT	ADHESION	STRENGTH	ANTI-WATER PROPERTY
1st Emb.	o ○	o ○	o ○
2nd Emb.	o ○	o ○	o ○
3rd Emb.	o ○	o ○	o ○
4th Emb.	o ○	o ○	o ○
5th Emb.	o ○	o ○	o ○
6th Emb.	o ○	o ○	o ○
7th Emb..	Δ~×	×	Δ
8th Emb.	Δ	Δ	Δ
9th Emb.	Δ	Δ	Δ
10th Emb.	○	Δ	○
11th Emb.	Δ	Δ	Δ
12th Emb.	Δ	○	o ○
13th Emb.	Δ	○	Δ
14th Emb.	Δ	○	Δ
Note : 1. The adhesion was detwermined by peeling ther cover film from the print. 2. The strength of the film was determined to be good, when the film was not harmed during the test for adhesion. 3. The anti-water property was determined to be good, when no water permeated between the cover film and the print, during 20 hours in which the print was kept in the water at a temperature of 20°C.

The above description has clarified that a cover film employable for protection of a print which is printed on a sheet of paper employable for printing conducted by employing a type of a printer which uses a water based ink or which is printed on a sheet of paper on which a film for expediting permeation of a water based ink into the paper and for causing clear printing thereon, is attached, for the purpose to protect the print from a potential external hazard particularly caused by rain unavoidable, when the print is kept outdoors, wherein the cover film has an advantage that the effects of the protection is durable for a long time and that the foregoing cover film can be attached on a print at a relatively low temperature for example 80° C, and a method for producing the foregoing cover film, have been successfully provided by this invention.

Claims

A cover film for protection of a print from the influence of weather comprising :
a film produced by coating an aqueous dispersion containing 50 through 500 weight portion of at least one ingredient of a group including ethylene, unsaturated carboxylic acid and unsaturated carboxylic ester, aliphatic conjugated diolefin monomer and vinyl monomer, 10 through 500 weight portion of a tackifier and 50 through 500 weight portion of a crystalline plasticizer which is liquefied at a temperature of 40° C, on a substrate.
A cover film for protection of a print from the influence of weather in accordance with Claim 1, wherein said tackifier is rosin, a derivatives of rosin, terpene or a derivatives of terpene.
A cover film for protection of a print from the influence of weather in accordance with Claim 1, wherein said crystalline plasticizer is dicyclohexyl phthalate, diphenyl phthalate, dihexyl phthalate, dihydro aviethyl phthalate, dimethyl isophthalate, sucrose benzoate, ethyleneglycol dibenzoate, trimethylolethane tri-benzoate, glyceride tri-benzoate, pentaerythritol tetra-benzoate, sucrose octacetate, tri-cyclohexyl citrate or N-cyclohexyl p-toluenesulfonamide.
A cover film for protection of a print from the influence of weather in accordance with Claim 1, wherein said substrate is a single layer film of polyethylene terephthalate or oriented polypropylene.
A cover film for protection of a print from the influence of weather in accordance with Claim 1, wherein said substrate is a plural layer film of polyethylene terephthalate or oriented polypropylene.
A cover film for protection of a print from the influence of weather in accordance with Claim 1, wherein said substrate is a single layer film of polyethylene terephthalate or oriented polypropylene which is coated with a film of polyethylene resin, ethylene vinyl which is coated with a film of polyethylene resin, ethylene vinyl acetate copolymer resin, ethylene acrylic ester copolymer resin, ethylene methacrylic ester copolymer resin, ethylene acrylate copolymer resin, ethylene methacrylate copolymer resin, ethylene acrylate acrylic ester copolymer resin or ethylene methacrylate acrylic ester resin,
A cover film for protection of a print from the influence of weather in accordance with Claim 1, wherein said substrate is a plural layer film of polyethylene terephthalate or oriented polypropylene which is coated with a film of polyethylene resin, ethylene vinyl which is coated with a film of polyethylene resin, ethylene vinyl acetate copolymer resin, ethylene acrylic ester copolymer resin, ethylene methacrylic ester copolymer resin, ethylene acrylate copolymer resin, ethylene methacrylate copolymer resin, ethylene acrylate acrylic ester copolymer resin or ethylene methacrylate acrylic ester resin.
A method for producing a cover film for protection of a print from the influence of weather comprising :
a step for coating an aqueous dispersion containing 50 through 500 weight portion of at least one ingredient of a group including ethylene, unsaturated carboxylic acid and unsaturated carboxylic ester, aliphatic conjugated diolefin monomer and vinyl monomer, a tackifier and a crystalline plasticizer which is liquefied at a temperature of 40 ° C, on a substrate.
A method for producing a cover film for protection of a print from the influence of weather in accordance with Claim 8, wherein said tackifier is rosin, a derivatives of rosin, terpene or a derivatives of terpene.
A method for producing a cover film for protection of a print from the influence of weather in accordance with Claim 8, wherein said crystalline plasticizer is dicyclohexyl phthalate, diphenyl phthalate, dihexyl phthalate, dihydro aviethyl phthalate, dimethyl isophthalate, sucrose benzoate, ethyleneglycol dibenzoate, trimethylolethane tri-benzoate, glyceride tri-benzoate, pentaerythritol tetra-benzoate, sucrose octacetate, tri-cyclohexyl citrate or N-cyclohexyl p-toluenesulfonamide.
A method for producing a cover film for protection of a print from the influence of weather in accordance with Claim 8, wherein said substrate is a single layer film of polyethylene terephthalate or oriented polypropylene.
A method for producing a cover film for protection of a print from the influence of weather in accordance with Claim 8, wherein said substrate is a plural layer film of polyethylene terephthalate or oriented polypropylene.
A method for producing a cover film for protection of a print from the influence of weather in accordance with Claim 8, wherein said substrate is a single layer film of polyethylene terephthalate or oriented polypropylene which is coated with a film of polyethylene resin, ethylene vinyl which is coated with a film of polyethylene resin, ethylene vinyl acetate copolymer resin, ethylene acrylic ester copolymer resin, ethylene methacrylic ester copolymer resin, ethylene acrylate copolymer resin, ethylene methacrylate copolymer resin, ethylene acrylate acrylic ester copolymer resin or ethylene methacrylate acrylic ester resin.
A method for producing a cover film for protection of a print from the influence of weather in accordance with Claim 8, wherein said substrate is a plural layer film of polyethylene terephthalate or oriented polypropylene which is coated with a film of polyethylene resin, ethylene vinyl which is coated with a film of polyethylene resin, ethylene vinyl acetate copolymer resin, ethylene acrylic ester copolymer resin, ethylene methacrylic ester copolymer resin, ethylene acrylate copolymer resin or ethylene methacrylate copolymer.