JPH059971U - Printing screen - Google Patents

Abstract

(57) [Summary] [Object] To provide a printing screen in which the adhesive strength between the screen base cloth and the photosensitive resin is high and the strength of the screen base cloth is not deteriorated. A printing screen comprising a photosensitive resin layer which is exposed, developed and fixed in accordance with a desired pattern on a screen base fabric made of monofilament having a diameter of 25 to 150 μm. A modified layer formed by corona discharge treatment is formed on the surface on the side where the photosensitive resin is adhered.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

  The present invention relates to a printing screen. To elaborate further, the book The idea is a screen base cloth made of monofilament and a desired pattern on it. An improved resin that has a high durability against repeated printing due to the formed resin layer. Screen for printing.

[0002]

[Prior art]

  Conventionally, in order to produce a printing screen, first of all synthetic fibers, especially polyester etc. The photosensitive resin solution is applied to one or both sides of the screen base fabric consisting of the monofilament of Visible through the original with the desired pattern by coating or adhering the photosensitive resin film Irradiate with light rays and / or ultraviolet rays. At this time, only the part of the resin layer that received the light A crosslinking reaction or a photolysis reaction occurs. After that, the soluble part of the resin layer is washed with water and chemicals. And so on to obtain a printing screen having a desired pattern.

[0003]   In such a printing screen, the contact between the photosensitive resin layer and the filament base cloth If the adhesion is weak, the resin layer will be peeled off by repeated printing. It becomes impossible to print repeatedly. In order to eliminate such problems, For Termonofilament base cloth, use this screen base cloth with alkaline aqueous solution. The weight reduction process is applied to improve the adhesive strength of the screen base cloth to the photosensitive resin. The method of increasing the durability and improving the repeated printing durability is adopted.

[0004]   However, in order to obtain satisfactory durable adhesion with this method, it is quite frustrating. Since it is necessary to perform severe alkali weight loss treatment, filaments with a particularly small fiber diameter The yarn has an extreme decrease in strength, which causes the screen There is a problem such as the cloth breaking.

[0005]

[Problems to be solved by the device]   In printing screens where monofilament base cloth is coated with photosensitive resin ,   (1) To strengthen the adhesion between the monofilament base cloth and the photosensitive resin, And   (2) Minimize the reduction in strength of the monofilament base fabric.

[0006]

[Means for Solving the Problems]

  The printing screen of the present invention is a monofilament having a diameter of 25 to 150 μm. Screen base fabric, and a photo-sensitive material on this base fabric according to the desired pattern. ・ Made of a photosensitive resin layer that has been developed and fixed, to give the feeling of the monofilament base cloth. Characterized by a modified layer formed by corona discharge treatment on the surface of the photo resin adhesive side It is what

[0007]

[Action]

  Due to the presence of the above corona discharge treatment modified layer, a monofilament base cloth and a photosensitive resin layer And the resulting printing screen has excellent repeatability. Eshi Printing durability can be demonstrated.

[0008]   The monofilaments useful in constructing the screen substrate used in the present invention are Natural fiber such as silk, inorganic fiber such as glass fiber, carbon fiber, metal fiber Fibre, regenerated fiber, for example, viscose rayon, cupra, semi-synthetic fiber, For example, di- and tri-acetate fibers and the like, and synthetic fibers such as nylon. 6, nylon 66, polyester (polyethylene terephthalate etc.) fiber, fragrance Group polyamide fibers, acrylic fibers, polyvinyl chloride fibers, polyolefin fibers and And polyvinyl alcohol fiber insolubilized in water or insolubilized in water.

[0009]   The diameter of the monofilament fiber is 25 to 150 μm, and this diameter is 25 μm. If it is smaller, the tensile strength of the monofilament is insufficient and it is easy to cut and It will be difficult. Moreover, when the diameter is larger than 150 μm, the accuracy is high and good. No print results are obtained.

[0010]   The photosensitive resin useful in the present invention includes a water-soluble polymer, for example, having a molecular weight of 130. Ester of polyvinyl alcohol of about 0 to 1500 and a compound having a photosensitive group Compounds, for example, the above-mentioned polyvinyl alcohol cinnamic ester, β-furyl Acrylic ester, α-cyanocinnamic ester, p-azidocinnamic Ester, β-styryl acrylic ester, α-cyano-β-styryl acrylic Ester, p-phenylenediacrylic ester, p- (2-benzoylvinyl) -Cinnamic ester, diphenylcyclopropene ester, etc. Photodimerization photopolymers such as tilbene compounds and α-phenylmaleimide compounds, And a hydroxyl group-containing polymer such as polyvinyl alcohol and a diazo compound or Is a resin material mixed with a photodegradable photopolymer such as an azide compound, and a polymer Acrylic ester group, methacrylic acid ester group, crotonic acid in the molecular chain or side chain Ester group, maleic acid ester group, fumaric acid ester group, itaconic acid ester Group, vinyl ester group, vinyl ether group, vinylbenzene group, allyl ether Group, photopolymerizable photopolymer having photopolymerizable photosensitive group such as acrylamide group What can be illustrated.

[0011]   The photosensitive resin used in the present invention may contain a sensitizer. Examples of such sensitizers include 5-nitroacenaphthene and N-acetyl-4-nitro- 1-naphthylamine, 2-ethylanthraquinone, 1,2-benzanthraquinone , Benzophenone, acetophenone, azobisisobutyronitrile, etc. You can

[0012]   The photosensitive resin is applied as a solution or film on the screen base cloth and dried, or Is affixed. The direct version, direct method, and indirect method can be used to create the screen version. You may use each.

[0013]   In the present invention, at least one surface of the screen base cloth, that is, the photosensitive resin is in contact with A modified layer formed by corona discharge treatment is formed on the surface to be attached. Corona discharge The reason is that a high voltage is applied between the roller that supports the base cloth and the electrode that is installed opposite to it. , Generate corona discharge and move the base cloth between the electrodes to process the surface of the base cloth one after another. It is something to do.

[0014]   The corona discharge treatment used in the printing screen of the present invention is shown in FIG. The pair of roll-shaped discharge electrodes as shown in Fig. It can be carried out continuously.

[0015]   In FIG. 1, a pair of roll-shaped discharge electrodes 1 and 2 are each a metal electrode core. 3 and 4 and non-electrically conductive resin layers 5 and 6 (for example, rubber layers) that cover them It is something. The electrode core 3 of one roll-shaped discharge electrode is connected to the high voltage power source 7, The electrode core 4 of the other roll-shaped electrode is connected to the ground 8. After going through the guide roll 9 The back surface 11 of the base fabric 10 sent in as a roll-shaped electrode is connected to the ground. The discharge electrode is moved at a constant speed (for example, 2 to 10 m / min) so as to be in contact with the peripheral surface of No. 2. To go. At this time, a predetermined voltage (100 to 200 V) is applied between the two roll-shaped electrodes 1 and 2. When applied, a corona discharge of 10 to 60 A is generated, and this corona discharge causes the base fabric 10 Surface 12 is subjected to treatment.

[0016]   The distance A between the peripheral surfaces between the electrodes is preferably 30 mm or less, and generally 5 to 20. mm. The base cloth 10 which has been subjected to the corona discharge treatment is passed through the guide roll 13 and then rolled. Wound to form 14.

[0017]   Spark gap method, vacuum tube method, solid state for corona discharge treatment A method etc. can be used.

In order to improve the surface workability of the base cloth, for example, the adhesiveness, it is preferable that the critical surface tension thereof be 35 to 60 dyn / cm, and for this purpose, the surface of the base cloth is 5 to 5 d. It is preferable to impart a treatment energy of 50,000 W / m ² / min, preferably about 150 to 40,000 W / m ² / min. The amount of energy to be applied (voltage, current amount, distance between electrodes, etc.) is determined in consideration of the width of the base cloth, processing speed, and the like. For example, when corona discharge is applied to a surface of a base cloth having a width of 2 m at a processing speed of 10 m / min, the output (power consumption) is preferably about 4 kW to 800 kW. However, it is not necessarily limited to this condition.

[0019]   The corona discharge device used for manufacturing the printing screen of the present invention is a conventional metal electrode. It may be of a mold. The performance of the high voltage power supply etc. of the corona discharge device can be set as desired. Can be specified. Other operating conditions for corona discharge treatment are model, device performance , And setting conditions can be arbitrarily selected.

[0020]   On the modified surface of the monofilament base fabric with the modified layer formed by corona discharge treatment Apply or stick a photosensitive resin and pass visible light through an original with a desired pattern. And / or irradiate with ultraviolet rays. After that, apply the required development and fixing process to it, Obtain the printing screen of the present invention.

[0021]   The photosensitive resin layer can be formed on one side or both sides of the base cloth. When forming the photo-resin layer, even if the opposite side of the base cloth is subjected to corona discharge treatment It doesn't matter. In this case, the photosensitive resin wraps around the opposite surface of the monofilament. May be effective in improving the adhesion durability between the base cloth and the photosensitive resin layer. .

[0022]

【Example】

  The present invention will be described in more detail with reference to the following examples.

Example 1 and Comparative Examples 1 and 2 Polyester monofilament cloth having the following structure: Warp Diameter: 30 μm Density: 250 threads / 25.4 mm Weft Diameter: 30 μm Density: 250 threads / 25.4 mm Corona discharge treatment was performed by the device shown in FIG.

The base cloth was fed between the pair of discharge electrodes at a speed of 10 m / min so that the one-sided layer of the base cloth was in contact with the peripheral surface of the roll-shaped electrode connected to the ground. Corona discharge treatment was continuously performed on the back surface of this base cloth at a distance A between both electrodes of 10 mm, a voltage of 160 V, a current of 18 amps and a maximum output of 8 kW (power consumption of 7.9 kW / hr). At this time, the diameter of the metal electrode core of both electrodes was 20 cm, the thickness of the resin layer was 2 mm (roll diameter 20.4 cm), the roll length was 2 m, and the discharge width was 1.92 m. At this time, the energy radiated on the sample surface was about 440 W / m ² / min.

[0025]   Table 1 shows the tensile strength of the obtained polyester monofilament base fabric having the modified layer. Shown in.

[0026]   Then, after wetting the modified polyester monofilament base cloth with water sufficiently, Attach a photosensitive resin film (AUTOTYPE, CAPILLEX35) on the surface of the After lightly pressure-bonding with a tool, it was dried at a temperature of 40 ° C. for 30 minutes. In the resulting laminate Adhesive strength between the photosensitive resin film and the monofilament base cloth Are also shown in Table 1.

[0027]

[Table 1]

[0028]   Comparative Example 1 is a case where the corona discharge treatment is omitted.   As Comparative Example 2, a polyester monofilament base cloth having the same structure as that described above was used with caustic saw. It is impregnated with a da water solution and subjected to alkali weight reduction processing by the pad steam method, The alkali-treated base fabric obtained by changing the weight loss rate between 3% and 40% Adhesion between the base material that has been subjected to the tensile strength and alkali treatment and the photosensitive resin film The strength was measured. The results are shown in Table 2.

[0029]

[Table 2]

[0030]   Also, using a high-pressure mercury lamp with an output of 7 kW, the laminate after sticking the photosensitive resin film Measures the adhesive strength between the photosensitive resin layer obtained by developing and irradiating with ultraviolet light for 3 minutes and the base cloth. The results also showed a tendency similar to the results shown in Table 1 and Table 2 and good. It was something.

Example 2 and Comparative Example 3 A polyester monofilament base fabric having the same structure as in Example 1 was subjected to corona discharge treatment in the same manner as in Example 1. Table 3 shows the adhesive strength of the modified base fabric to the photosensitive resin film (then, the same operation as in Example 1 was repeated) and the change with time of the adhesive strength. The tensile strength of the modified base fabric was equivalent to that of the untreated product treated with corona discharge.

[0032]   Comparative Example 3 is a case where the corona discharge treatment is omitted.

[0033]

[Table 3]

[0034]   Also, the photosensitive resin film-attached laminate was irradiated with ultraviolet rays in the same manner as in Example 1. When the adhesive strength between the photosensitive resin layer and the base cloth obtained by spraying and developing was measured, Table 3 shows Results similar to those shown were obtained.

Example 3 and Comparative Example 4 A polyester monofilament base fabric having the same structure as in Example 1 was subjected to corona discharge treatment in the same manner as in Example 1. Next, this modified polyester monofilament base cloth was fixed to an aluminum frame of 50 cm × 50 cm by applying tension to sufficiently contain water, and then a photosensitive resin film (CAPILLEX35) was attached thereto, and the temperature was kept at 40 ° C. Dry at temperature for 30 minutes. After that, the surface was covered with originals having various dot patterns with different line widths, and ultraviolet rays were irradiated for 3 minutes using a high-pressure mercury lamp with an output of 7 kW. This was subjected to a predetermined development treatment with water to obtain a printing screen plate. The results of the adhesiveness (cellophane tape peeling test) of this product are shown in Table 4. In Comparative Example 4, the corona discharge treatment was omitted.

[0036]

[Table 4]

[0037]   Note: * The peel test was repeated 5 times.   (Criteria)     ○: Does not peel     Δ: Partial peeling occurs     ×: peeled off entirely

[0038]

[Effect of device]

  The printing screen obtained by the present invention has physical properties such as tensile strength of fibers. The adhesive force between the photosensitive resin and the screen base cloth is strengthened without being damaged. Therefore, the durability against repeated printing becomes excellent.

[0039]   Also, since the adhesive force between the screen base cloth and the photosensitive resin is strong, the adhesive area is Even if it is small, it is possible to obtain an adhesive strength that can withstand practical use. It is possible to obtain a printing screen having a pattern with a small line width.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a corona discharge treatment device for forming a corona discharge modifying layer on a desired surface of a monofilament base fabric in a printing screen of the present invention.

[Explanation of symbols]

1, 2 ... Discharge electrodes 3, 4 ... Electrode core 5, 6 ... Resin layer 9, 13 ... Guide roll 10 ... Base cloth

Claims (4)

[Scope of utility model registration request] 1. A monofilament screen base cloth comprising a screen base cloth made of a monofilament having a diameter of 25 to 150 μm, and a photosensitive resin layer which is exposed, developed and fixed on the base cloth according to a desired pattern. A printing screen, characterized in that a modified layer by corona discharge treatment is formed on the surface of the photosensitive resin adhered side. 2. The printing screen according to claim 1, wherein the monofilament is selected from natural monofilament, inorganic monofilament, regenerated cellulose monofilament, semi-synthetic monofilament, and synthetic monofilament. 3. The printing screen according to claim 1, wherein the photosensitive resin layer is formed on only one surface of the base cloth. 4. The printing screen according to claim 1, wherein the photosensitive resin layer is formed on both sides of the base cloth.