JPH05286226A - Printing method of pet film - Google Patents

Abstract

PURPOSE: To improve clearness, heat resistance and solvent resistance of printed color of PET products by infiltrating the printed ink after printing into clearance of PET film crystallites under a specific temperature and pressure. CONSTITUTION: A PET film wound in a roll is subjected to a tensile force of about 2 kg, and the film and a patterned mold paper are presses under a pressure of 6-8 kg/cm<2> and advanced with a speed of 10-20 m/min. Both are passed on a heating roller of 175-220 deg.C to print the printing ink on the mold paper on the PET film. After printing, the film and the paper are quickly introduced into a freezing room to cool down to a temperature lower than 10 deg.C, recover the crystalline state of the film crystals, combine printed ink with crystallites to fix. Then, after the mold paper and the PET film are separated, the printed PET film is wound into a roll to obtain a product.

Description

Detailed Description of the Invention

[0001]

The present invention relates to PET (polyethylene
(Terephthalate: Abbreviated as PET) It is related to the printing method of the film, and its main feature is that it is exactly adapted to the physical properties and melting properties of the PET material, and gives a tensile force of about 2 kg to the PET film that is rolled up into a cylindrical shape. , So as not to cause a relaxation state, 6-8kg / cm
^While pressing by the pressure of ² , while moving by the roller at a speed of 10-20m per minute, press it with the mold paper and then pass through the heat roller at 175-220 ℃ high temperature, the gap of the pet crystal To allow the printing ink on the mold paper to penetrate into the pet's film, and finally to add rapid cooling again to stabilize the printing ink and combine with the pet's film to increase the product thickness. It is a printing method that maintains the same thickness as the original PET film.

[0002] The method of printing a pet film is mainly to give a proper amount of tensile force to the pet film which is rolled up in a cylindrical shape, and to control the pet film so as not to cause a loose state, and then to be laminated with a mold paper. It progresses at a speed of 10 to 20m every minute, and 1
After passing through a heat roller having a temperature of 75 to 220 ° C. and a pressure of 6 to 8 kg / cm ² , the PET film is printed with a hard printing ink while obtaining a very good truthfulness through cooling.

[0003]

2. Description of the Related Art Pets are nowadays widely applied materials, which are aggregates that exhibit a crystalline state, and the characteristic of them is that when they are made into a model through biaxial stretching, the mechanical strength becomes great. In addition, it has low wicking rate, moisture rate, and air permeability, and has excellent dimensional stability. It withstands heat, cold, and solvents, and its application is outside the heat insulation film of automobiles. Widely applied to rubber, tape, wrapping paper, trademark, nameplate, toys, sun glasses, photo plates, etc. However, since the above shows the characteristics of PET film, it gives rise to important difficulties in printing and dyeing which are necessary for its application.

1. Conventional printing method with smooth material on the surface: Traditional printing method is decided by looking at the characteristics of the printed material, it is metal like material with smooth surface, generally plastic, etc.
This method increases the thickness of the prints and makes the prints and prints adhere to each other like the coating of the print ink on the paper with another layer of resin, which makes the print ink and the prints adhere to each other. All the properties are poor, and the property of withstanding heat, exfoliation, washing with water, etc. is even less desirable (as shown in FIG. 1).

2. Conventional printing methods for rough materials on the surface:
It is similar to the printing of spun fibers of artificial fibers such as polyesters, and the printing ink on the mold paper is completely clogged and adheres to the gaps on the printed product surface when printing is completed, and As described above, the biggest drawback of this method is that the position of the printing ink is lower than the original position because the printing ink reaches the purpose of adhering the printing ink to the printed matter by utilizing the method in which the printing ink fills up and adheres. Therefore, the veracity becomes poor, and when it is attracted to the printed matter (this method is generally applied to a soft material), it is also poor in exfoliation and water resistance (as shown in FIG. 2).

3. Conventional direct printing method of PET film: Due to the characteristic of PET film, its printing is also limited, and since PET film is not applied in the previous printing method, it is processed by general printing technology, and half tone is applied. -For block printing, photogravure printing, phototype printing, etc., the product to be printed is also the conventional printing method with smooth surface as described above.
The strength and authenticity of the printing are also poor, and heat, peeling, and
It also fails to withstand washing, and, especially for bare-footing, increases its thickness after printing, which does not meet the strict requirements of certain industrial film thickness limits (as shown in Figure 1).

[0007]

In order to eliminate the drawbacks associated with the above-mentioned technique, if a printing method that exactly adapts to the physical properties and melting properties of the PET film can be created, it is assumed that the thickness will not increase after printing. In addition, the printed matter (printing ink) can be more tightly bonded to the PET film, and it can withstand water, heat and chemicals, and enhances the printing authenticity as well as the characteristics of the PET film itself. Based on this idea, the present invention has been made, which truly expresses the original color of printing ink, which is an ideal creation with new practical and industrial values.

[0008]

In other words, the present invention provides a kind of printing method for pet film, which is designed with physical properties and melting property of the pet film as the basis. ~ 220 ℃ temperature and 6
Under the conditions of a pressure of ~8kg / cm ^2, permeates the printed ink after printing gap PET film Akirakarada maintained when completing the printing, the thickness of originally product thickness PET film This is the main purpose of the present invention.

The present invention provides a method for printing a pet film, which is combined with a process of rapidly cooling at a suitable rotation speed by a printing method of penetrating a printing ink into a pet film crystal using the above. hand,
The printing ink has high authenticity and can withstand washing with water, withstands heat,
It is another object of the present invention to endure chemicals. Other objects and advantages of the present invention will be further clarified by detailed description in combination with the drawings.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The special structure and its technical means and features which are used to achieve the above-described designing object of the present invention will now be described in detail with reference to the drawings. Referring to FIG. 1, it is a cross-sectional side view of a product made by a traditional printing method with a smooth material on the surface and a conventional method of directly printing a pet film, in which a smooth material or a pet material is provided on the surface. Since the resin layer 102 is used as an intermediary between the film 100 and the printing ink layer on the surface, or the resin layer 102 is mixed and adheres, the drawbacks are as described above.

Next, referring to FIG. 2, it is a side cross-sectional view of a product produced by a traditional printing method having a coarse substance (fiber material) on the surface, of which the surface of the fiber material or the like. The printing ink 201 printing of the poor material 200 is stuck in the gaps of the surface when printing and sticks to the full, this method is only applied to textiles, but it is curved into the fibers of the printed matter. As mentioned above, not only can the original design not be transparent and beautiful, but also the veracity does not apply to the printing of pet films. Furthermore, FIG.
With reference to the displays of 4 and 4, there are illustrated a step block chart and a flow sheet of the printing method of the present invention, and the main steps and flow sheets of the present invention are: 1. Approximately 2k on PET film 10 rolled up in a cylindrical shape
Giving a tensile force of g: 2. Both the above-mentioned PET film 10 and the patterned mold paper 20 are pressed by a pressure of 6-8 kg / cm ² and controlled so as to move at a speed of 10/20 m every minute. After passing through the press, the PET film 10 and the mold paper 20 are combined with the above pressure and the advancing speed, and passed through the heating of the heat roller 30 at a temperature of 175 to 220 ° C.
Print 0 to within the PET film layer: After printing, the PET film 10 and the mold paper 20 quickly pass through the freezing room 50, and are rapidly frozen at a temperature of 10 ° C. or less, so that the printing ink 40 is stably contained in the PET film 10 layer. 4. Intimately bind to the crystal (not shown) of: The mold paper 20 and the pet film 10 are separated, and after the printing is completed, the pet film 10 is rolled up into a cylindrical shape to become a product.

As described above, in the printing method of the present invention, the temperature of the heat roller is 175 to 220 ° C., the pressure of the press is 6 to 8 kg / cm ^2, and the speed is 10 to 20 m per minute. Ensure the effect of printing, so that the three conditions can be adjusted and complemented with each other within that range,
For example, the temperature of the heat roller may be adjusted low to increase the pressure of the press or decrease the speed of progress to ensure the progress of printing.

Due to the smooth crystal aggregates on the surface of the pet film 10, it is generally transported as a cylindrical shape, convenient for the operation of the other steps of the present invention, and provides the pet film with an appropriate amount of pulling force for relaxation. A tensile force of about 2 kg is generally most suitable so as not to cause a condition: mold paper 20 and PET film 10 as well.
Presses make printing steps easier,
Besides, PET film 10 and mold paper 2
The progressing speed of 0 is also related to the progressing time and effect of printing. Therefore, after checking the pattern of printing by setting the temperature of the heat roller 30, the power of the press and the speed of progressing are appropriate. In general, the pressing force and the advancing speed are generally 10 to 20 m per minute, which is most suitable: With respect to the setting of the temperature of the heat roller 30, the pet film 10 is an aggregate of crystals. Since the applicant obtained from the result of the experiment that the gap between the crystal bodies of 80 ° C. or lower still does not change due to the frequency of the melting temperature, the conventional printing is advanced and the printing ink 40 for printing is printed. When it is illegal to penetrate into the film layer 10 and the temperature is 175 ° C. or higher, the progress of printing is achieved after combining with the force of the press and the speed of progress, and as shown in FIG. The result of Based on this, as can be seen from the test when the printing of the pet film 10 proceeds, the extent to which the printing ink 40 penetrates into the pet film layer 10 and the temperature of the heat roller 30 when printing are very high. There is a large relationship, and the change in the size of the gap between the crystal bodies of the pet film layer 10 (percentage of the degree of printing)
Is from 175 ° C. to about 220 ° C., above 220 ° C. the PET film 10 begins to soften and the crystals melt, which causes the temperature of the heat roller 30 to fall between 175 and 22 ° C.
The temperature is set to 0 ° C. and the most suitable temperature is about 180 to 210 ° C. When printing is finished in this case, the printing ink 40 on the mold paper has about 80 to 90% or more in the PET film layer 10. Penetrate. Further, in order to stably and regulate the temperature of the heat roller, if the heat box 60 is provided outside the heat roller 30, the requirement can be reached.

Upon rapid cooling after the printing of the present invention, the PET film crystals are quickly restored to their normal state, and the printing ink 40 of the printing is stably bound in the PET film layer 10, which is about Use the most suitable cooling in a freezing room below 10 ° C. Referring to FIG. 6, the structure of the product formed by the above printing method is as follows. When the PET film 10 and the mold paper 20 are pressed, the printing ink 40 and the PET film 10 are closely adhered to each other. When the film 10 and the mold paper 20 pass through the heat roller 30, the printing ink 40 enters into the PET film layer 10 due to the change in the gap between the crystals of the PET film layer 10, cools, and then molds. When the paper 20 separates, the printing ink 40 has already penetrated into the PET film layer 10 and has a stable and true fixation between the crystals so that the total thickness of the PET film 10 is equal to the printing ink 40. It does not increase due to penetration.

[0015]

As can be seen from the above summary, the printing method of the present invention thoroughly improves the drawbacks of the printing of pet films in general, and makes the printing color of the product clear and true. -Its resistance to physical properties such as heat, water, exfoliation and solvent, and its solubility is further superior.

[Brief description of drawings]

FIG. 1 is a cross-sectional side view of a product obtained by a traditional printing method with smooth physical properties on the surface and a conventional method of directly printing a pet film.

FIG. 2 is a cross-sectional side view of a product produced by a traditional printing method with a poor material (textile) on the surface.

FIG. 3 is a diagram showing a step block chart of the printing method of the present invention.

FIG. 4 is a flow sheet explanatory diagram of a printing method of the present invention.

FIG. 5 is a curve diagram of a temperature at which printing of a pet film progresses and a temperature at which printing is easily performed.

FIG. 6 is a cross-sectional view of a transitional side surface of a product in the printing process of the present invention.

[Explanation of symbols]

 10 PET film 20 Mold paper 30 Heat roller 40,201 Printing ink 50 Freezing room 60 Heat box 100 Smooth substance or PET film on the surface 101 Printing ink layer 102 Resin layer 200 Roughness of the surface of textiles, etc. Substance

Claims (2)

[Claims] 1. A polyethylene rolled up in a cylindrical shape.
A tensile force of about 2 kg is applied to the terephthalate (PET) film so as not to cause a relaxation state: (2) While pressing the above PET film and the patterned mold paper with a pressure of 6 to 8 kg / cm ² , It is controlled so that it progresses at a speed of 10 to 20 m per minute: (3) The pet film and mold paper that have passed the pressing are combined with the above pressure and the progressing speed, and 175
Through the heating of a heat roller at a temperature of ~ 220 ° C,
Print the printing ink on the mold paper up to the PET film layer: (4) After printing, print the PET film and mold
The paper quickly passes through the freezing room and rapidly freezes it at temperatures below 10 ° C. to restore the crystalline state of the crystals in the film layer above and combine the printing ink with the crystals. (5) A method for printing pet film, characterized in that the mold paper and the pet film are separated, and after the printing is completed, the pad film is rolled up into a cylindrical product to form a product. 2. The temperature of the heat roller is 175 to 22.
0 ℃, compression pressure is 6-8kg / cm ² and 1 per minute
The printing of pet film according to claim 1, characterized in that the three conditions can be adjusted to each other within the range so as to proceed at a speed of 0 to 20 m and compensate for each other to ensure the printing effect. Method.