JP2002337471A - Screen gauze - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screen gauze to which a UV-sensitive resin adheres excellently, which causes no problem of falling-off of the UV-sensitive resin therefrom even in repetition of printing, which is hardly torn in stretching and has an excellent quality and which is hardly torn even in the use in repetition and free of a shift of a mesh in squeegeeing. SOLUTION: In the screen gauze of which the warp and the woof are constituted of monofilaments respectively, at least the warp and/or the woof of the monofilaments constituting the screen gauze has the shape of a multifoliate cross section and the number of leaves is three to ten. The UV-sensitive resin adheres to recesses of the multifoliate section. By using the monofilaments for the warp and the woof of the screen gauze, the physical properties of the warp and the woof are made uniform. The monofilaments are constituted of a polyester and contain a matting agent in a proper amount.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a screen gauze used for screen printing. More specifically, it is composed of monofilaments, has good adhesion of a UV photosensitive resin for drawing a printing pattern, is used for screen printing which is print printing on cloth, such as clothing and sheet material, and has a large aperture. The present invention relates to a screen gauze that is a mesh fabric.

[0002]

2. Description of the Related Art As screen gauze for printing, silk, stainless steel and the like have long been used as materials. recent years,
Mesh fabrics made of synthetic fibers are widely used because of their excellent flexibility, durability, cost performance, and the like. In particular, polyester filaments are water resistant,
It has excellent dimensional stability and is ideal for screen gauze.

[0003] Printing (printing) prints on cloth for clothing
Since it is necessary to load ink relatively thick from the demands of quality, durability, etc., the thickness of the screen gauze is also required, so that it is woven with a monofilament having a relatively large single yarn diameter. However, screen gauze woven from monofilaments with a large single yarn diameter for both warp and weft have sufficient thickness, but due to the structure of the monofilament itself, adhesion to the UV photosensitive resin for drawing print patterns and patterns is poor. bad. Therefore, when printing is repeatedly performed, a problem occurs in which the UV photosensitive resin drops off.

In order to enhance the adhesion of a printing emulsion such as a UV photosensitive resin, a composite monofilament for screen gauze disclosed in Japanese Patent Application Laid-Open No. 1-132829 has a core-sheath composed of two components, the core component being polyester and the sheath component being nylon. The composite monofilament of the structure is disclosed in JP-A-2000-3140.
In the monofilament for screen gauze disclosed in JP-A No. 33, a core-sheath composite monofilament in which both the core component and the sheath component are polyester is proposed. However, using a core-sheath composite type monofilament has problems such as an increase in cost, a difference in strength depending on the core-sheath ratio, and a shift in the core.

[0005] In order to prevent the UV-sensitive resin from falling off, a so-called mono / multi-screen gauze has conventionally been used in which a monofilament is used for the warp and a multifilament having a plurality of single yarns is used for the weft. Is widely used. When a multifilament twisted weft is used, the UV-sensitive resin enters between the single yarns, and the UV-sensitive resin is three-dimensionally fixed to the screen gauze. Shedding is reduced. This method using mono / multi-screen gauze is generally used, for example, for print printing of T-shirts.

However, since this mono / multi-screen gauze is composed of yarns having different characteristics of a warp yarn and a weft yarn having a twist and a yarn having no twist, the tensile strength and tensile elongation in the warp and weft directions, so-called S-type yarns are known. The S-curves are different, and when stretched with the same tension, the elongation in the weft direction is different. Therefore, when the screen is stretched, a portion of the screen gauze that particularly hits the corner of the frame is apt to be subjected to an oblique force, not to the warp or weft direction of the woven fabric, so that the screen gauze is likely to be broken.

The multifilament used for the mono / multiscreen gauze is generally 33 dtex to 78 dtex. For example, 33dtex6fil. In, the number of twists is about 1000 turns / m. Therefore, the cost for twisting, equipment and time for twisting are required, and the efficiency is extremely low. In addition, twisted yarn is manufactured by a method such as Italy type, ring type, double twister, etc., but these general twisting methods are based on the fact that the ballooning point fixing guide of the twisted yarn and the position of unwinding and winding change. The number of twists in the filament is partially changed. In general, since the variation in the number of twists occurs around 10%, continuously driving the yarns having different numbers of twists into the weft naturally adversely affects the quality of the gauze.

Since screen gauze is used repeatedly for printing, it is preferable to increase the number of printable sheets in order to improve the productivity. The replacement of the printing plate is to prevent the screen gauze from stretching due to the fatigue of the screen gauze due to repeated squeezing at the time of repetitive printing, and to prevent printing from shifting. Therefore, the raw yarn used for the screen gauze is preferably a high modulus, high strength yarn. However, in general, high-strength yarns have low elongation and are easily damaged on the yarn surface by friction during twisting, and are liable to fuzz and surface scraping. There is a risk of tearing at times.

Further, when the twisted yarn comes into contact with a solid, the twist shape hinders the movement of the twisted yarn in the length direction of the twisted yarn. But tend to be slippery. Therefore, in mono / multi-screen gauze, misregistration may occur due to friction in squeezing of printing.

Further, the mono / multi-screen gauze obtains a wide opening, that is, a wide opening by converging the single yarn by making the multi-filament behave as if it is a single yarn. It is necessary to twist a large number of multifilaments. However, by using a twisted yarn, the modulus of the SS curve of the yarn decreases, that is, the yarn becomes weak and easily stretched. This is unsuitable for printing with a large tension when printing a large number of prints and in order to reduce misalignment at the beginning and end of printing and perform printing with good reproducibility. .

[0011]

SUMMARY OF THE INVENTION The present invention relates to a screen gauze composed of a monofilament, which comprises a warp and / or a warp.
Alternatively, by using a monofilament having a multi-lobed cross section for all or a part of the weft, the U
It is an object of the present invention to provide a screen gauze that has good adhesiveness of a V photosensitive resin and does not cause a problem of falling off of the UV photosensitive resin from the screen gauze even after repeated printing.

[0012]

The present invention relates to a screen gauze made of monofilaments, wherein the warp and the weft contain monofilaments having a multi-lobal cross-section.

The present invention provides a screen gauze composed of monofilaments, wherein at least 50% of the monofilaments of either the warp or the weft constituting the screen gauze have a multi-lobal cross-sectional shape. The screen gauze is characterized in that monofilaments having a multi-lobal cross-sectional shape are evenly distributed on the screen gauze.

According to the present invention, in a screen gauze composed of monofilaments, at least 25% of the monofilaments constituting the screen gauze have a multi-lobal cross-sectional shape, and the cross-sectional shape has a multi-lobal cross-sectional shape. Wherein the monofilament is uniformly distributed on the screen gauze.

It is preferable that the shape of the multi-leaf cross section is from 3 leaves to 10 leaves.

Preferably, the monofilament is made of polyester.

Preferably, the monofilament contains a matting agent.

[0018]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a U / G screen equivalent to a mono / multi-screen gauze used for screen printing on clothing or the like.
V photosensitive resin adhesiveness, and in order to obtain a screen gauze having the same quality and strong stability as a screen gauze using a monofilament for both warp and weft, the warp and weft of the monofilament constituting the screen gauze ,
The present invention relates to a screen gauze including a monofilament having a multi-leaf cross-sectional shape of, for example, 3 leaves or more and 10 leaves or less.

The multi-lobal cross-sectional shape in the present invention is a cross-sectional shape having three or more concavities and convexities, and the concave portion has a narrowed shape or an acute angle shape, and is used for fixing a resin. It is easy to do. The convex part is called a leaf, for example, 3
A leaf refers to having three convex portions in a cross-sectional shape. FIG. 2 is a cross-sectional view showing an example of a three-lobe cross-sectional shape.
FIG. 4 is a cross-sectional view showing an example of a four-leaf cross-sectional shape, FIG. 4 is a cross-sectional view showing an example of a five-leaf cross-sectional shape, FIG. 1 shows a cross-sectional view illustrating an example of an 8-leaf cross-sectional shape. The multi-lobal cross-sectional shape is not particularly limited. For example, as shown in FIGS. 2 to 6, the concave portion forms a sharp acute portion as a narrowed narrow portion, and the convex portion is rounded. It is preferable that the shape is equal, the shape is arranged uniformly along the circumference of a circumscribed circle where all the convex portions come into contact, and formed like a petal.

When the screen gauze includes a monofilament having a multi-leaf cross section, a UV photosensitive resin for drawing a print pattern is adhered to the concave portion having the multi-leaf cross section, and is used as a screen gauze.

The number of leaves of the filament having a multi-leaf cross section is 3 or more, preferably 3 or more and 10 or less. Particularly preferably, the number of leaves is 4 or more and 8 or less, more preferably 5 or 6 leaves. 5 or 6 leaves are U
V It is most preferable from the viewpoint of the adhesive property of the photosensitive resin, the productivity and the quality of the screen gauze.

As shown in FIG. 7, the multileaf is determined by the ratio (r / R) of the radius (r) of the inscribed circle where all the concave portions come into contact and the radius (R) of the circumscribed circle where all the convex portions come into contact. When the cross-sectional shape is represented, r / R is not less than 0.3 and not more than 0.8
The following is preferred. In particular, r / R is preferably 0.4 or more and 0.7 or less, and more preferably 0.5 or more and 0.6 or less.

The cross-sectional shape of the two-leaf yarn is, for example, as shown in FIG. This shape is the same as a so-called flat cross-section yarn, so that the UV photosensitive resin is not three-dimensionally fixed in the concave portion. Also, since the two leaves are similar in flat cross-section yarn, the projected area of the wide surface and the narrow surface is greatly different, so that the mesh (plain weave, twill weave) woven with such yarn is very frustrating. In other words, the surface has an uneven appearance due to unevenness of eyes, uneven gloss and reflection. When such an irritated mesh is used, a wide area and a narrow area of the projected area are randomly present in the ink passage flow path of the screen gauze, and the passage of the printing ink is not uniform,
As a result, uniform and clean printing cannot be performed.

On the other hand, when the number of leaves increases, the cross-sectional shape becomes very close to a round cross-section, and a three-dimensional anchor effect that the UV photosensitive resin enters the concave portion on the yarn surface, in other words, the photosensitive resin And the effect of making it difficult to peel off decreases. In addition, in the production of filaments with a large number of leaves, the shape of the spinneret in melt spinning is complicated, raising the production cost of the spinneret, difficult to manage to reproduce the same cross-sectional shape, sublimation to the surface of the spinneret during melt spinning Acceleration of foreign matter accumulation such as material and matting material causes a decrease in stable productivity. Therefore, the effect of the present invention is reduced when eleven or more leaves are present, and various negative factors increase.

In the present invention, the number of leaves of the filament having a multi-lobed cross-sectional shape is three or more because the filament has a three-dimensional anchor effect and the difference in projected cross-sectional area due to the rotation of the fiber axis is small. The quality of the screen gauze and the quality of the prints printed using the screen gauze are good.

However, even if the shape is similar to the three-lobe cross section,
As shown in FIG. 8, the concave portion is almost flat and the convex portion is almost 6
The triangular cross-section yarn of 0 ° is widely used to increase the gloss of synthetic fibers such as polyester and nylon, but the UV-sensitive resin is an anchor that enters the narrow portion of the yarn surface, that is, the concave portion three-dimensionally. The effect of preventing resin peeling due to the effect cannot be expected.

The size of the dot of the UV-sensitive resin is usually
It is about the width of two adjacent yarns of the warp or weft of the screen gauze used in the present invention. Therefore, the UV photosensitive resin is adhered to the monofilament having a multi-leaf cross section,
In order to obtain a screen gauze having good absorbability of a photosensitive resin, among screen gauze constituted by monofilaments, at least 50% of one of the monofilaments of either the warp or the weft has a multi-leaf cross-section, and the screen gauze is formed. Either dispose monofilaments having a multi-leaf cross-section on the top, or make at least 25% of the monofilaments constituting the screen gauze have a multi-leaf cross-section, and place monofilaments having a multi-leaf cross-section on the screen gauze without bias It is preferable to arrange them. Particularly preferably, among the monofilaments of the screen gauze, 50% or more of monofilaments having a multi-lobe cross section are used,
More preferably, it is used 100%.

The cross-sectional shape of the multifilament monofilament used in the present invention does not need to be the same for both the warp and the weft, and may be a combination of different cross-sectional shapes. Further, it is not necessary to unify the cross-sectional shapes of the filaments having a multi-lobed cross-sectional shape used in the warp or the weft. By using a multi-leaf cross section,
Since the UV photosensitive resin only needs to be incorporated into the screen gauze, the filaments used need not have the same cross-sectional shape.

The screen gauze of the present invention has a plain weave or twill weave of 50 mesh / inch (19.7 mesh / inch).
cm) to 255 mesh / inch (100 mesh / cm) or less. Particularly preferably, 13
0 mesh / inch (51 mesh / cm).

The fineness of the monofilament of the present invention is 5d
It is preferably from tex to 110 dtex, particularly preferably from 20 dtex to 45 dtex.

Although the polymer used in the present invention is not particularly specified, for example, polyethylene terephthalate (P
ET), polyester such as polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), nylon (NY), polyphenylsulfone (PPS),
And polyether ether ketone (PEEK). Particularly preferred is polyester, particularly polyethylene terephthalate (PET), from the viewpoints of shape stability, chemical resistance, production cost, operability and the like required by screen gauze.

In order to cure the UV photosensitive resin adhered to the screen gauze, the screen gauze is irradiated with UV light. In order to prevent halation at that time, an appropriate amount of titanium oxide particles or the like is added to the polymer. It is preferred that a matte dulling agent is incorporated. The amount of the dulling agent is preferably 0.2% by weight or more, particularly preferably 0.3% by weight or more and 0.5% by weight or less. For example, a substance obtained by kneading 0.5% of a matting dulling agent into a polymer is used.

The material to be adhered to the screen gauze of the present invention is not limited to the UV-sensitive resin, and any other resin or printing emulsion can be used as long as it can enter the concave portion of the cross section of the monofilament.

[0034]

EXAMPLES Examples and comparative examples of the present invention will be described below in detail, but the present invention is not limited by these examples.
The evaluation in the examples was performed according to the following method.

With respect to the breaking elongation and the intermediate modulus,
The examination was performed as follows. According to JIS-L-1013, it is a constant-speed elongation type, using a general tensile tester, the sample length of the monofilament used for the screen gauze is 20 cm, the tensile speed is 20 cm / min. The elongation and the stress at break were recorded. The breaking strength was determined by the stress value (cN) when the sample was broken, and the breaking elongation was determined by the elongation (%) when the sample was broken. The intermediate modulus is the stress value (cN) when the tensile elongation of the sample is 5%.
Was 5% modulus.

The UV-sensitive resin adhesion was examined as follows. After weaving the filaments, scouring and setting are performed to prepare a screen gauze of 130 mesh / inch (50 mesh / cm), a diazo resin type UV photosensitive resin is applied to the screen gauze with a thickness of 12 μm, and drying is performed. After that, dots of 0.2 × 0.2 mm were exposed at intervals of 0.2 mm. Thereafter, the exposed screen gauze was washed and dried to obtain a screen gauze on which photosensitive resin dots were printed. On the screen gauze printed with these dots,
After applying Scotch Mending Tape # 810 (trade name) and rubbing it back and forth 10 times by hand, the tape was peeled off. Adhesion was evaluated by the average number of dots transferred per 10 cm of the tape length.

Regarding the quality, the screen gauze obtained by weaving, scouring and setting is visually judged, and if the appearance is not irritated, the quality is good. If the appearance is irritated, the quality is poor. X was given as an object, and Δ was given if the appearance was irritating in the middle.

The monofilament and the multifilament were spun as follows. As the polymer, polyethylene terephthalate having an intrinsic viscosity of 0.64 was used, and a matting agent containing 0.5% of titanium oxide particles was used. The intrinsic viscosity (IV) was measured at a temperature of 35 ° C. using orthochlorophenol (OCP) as a solvent.

For spinning, a conventionally known melt spinning apparatus was used. The spinning is performed at a speed of 1000 m / min.
After about one day, the undrawn yarn obtained was preheated with a roller heater at a temperature of 95 ° C., and then drawn to a boiling water shrinkage of 8 to 1.
Heat set with a roller heater so that it becomes 0%,
The film was wound at a speed of 800 m / min. The draw ratio and the undrawn yarn fineness are such that the obtained drawn yarn has a fineness of 33 dte.
x, the elongation at break was adjusted to be 30%. As a mouthpiece, a circular orifice having a diameter of 0.35 mm was used for a monofilament having a round cross section. For a multifilament having 6 single filaments, a circular orifice having a diameter of 0.25 mm was used for a die. The multifilament monofilament is shown in FIG.
As shown in FIG. 12, a die having a circular orifice 1 connected by a slit 2 was used. At this time, the width, length, molten polymer temperature, and the like of the slit 2 were adjusted so as to obtain an appropriate shape in each cross-sectional shape so as to form a multi-leaf shape. However, only multifilament,
After giving a twist of 1000 times / m using an Italy type twisting machine, heat setting was performed at 130 ° C. for 30 minutes. The filaments obtained as described above were used for warp and weft and woven to obtain screen gauze. Table 1 shows the results.

[0040]

[Table 1]

In Experiment 7, the non-twisted multifilament was used for the warp and the weft, but the screen gauze could not be printed because the multifilament was widened, there was no opening space, and there was no portion where ink came out.
Since it was not applied as a screen gauze, the gauze quality and the number of resin strips were not examined.

As shown in Table 1, the use of monofilaments having a cross-sectional shape within the range of the present invention and not less than 3 leaves and not more than 10 leaves a high balance between the quality of the screen gauze and the adhesiveness of the UV-sensitive resin. It is possible.

As a result of this experiment, it was also found that the toughness (strength × elongation) of the yarn tended to decrease somewhat as the number of leaves in the multi-leaf cross section increased. This means that the cross-sectional area of the die for obtaining the multi-leaf cross-sectional shape becomes large, and the discharge polymer flow rate and spinning tension of the center part of the yarn and the surface layer differ,
This is presumed to be the reason why a phenomenon occurred as if yarns having different spinning speeds were spun at the same time.

[0044]

The present invention provides a screen gauze composed of monofilaments, in which all or a part of the warp and / or weft yarns are monofilaments having a multi-lobed cross-sectional shape. It is possible to provide a screen gauze that has good adhesiveness of the resin and does not cause a problem of the UV photosensitive resin falling off from the screen gauze even after repeated printing.

Further, by using a monofilament for the course of the screen gauze, the unbalance of the course can be prevented, the physical properties of the course are uniform, it is hard to be broken at the time of gauze and repeated use, the quality is good, the twist direction and ski The misalignment due to the jing can be prevented, and the effect that the twist of the multifilament is not required can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a two-lobe cross-sectional shape which is a comparative example of the present invention.

FIG. 2 is a cross-sectional view showing an example of a three-lobe cross-sectional shape according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing an example of a four-lobe cross-sectional shape according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing an example of a five-lobe cross-sectional shape according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view showing an example of a six-leaf cross-sectional shape according to an embodiment of the present invention.

FIG. 6 is a cross-sectional view showing an example of an eight-lobe cross-sectional shape according to an embodiment of the present invention.

FIG. 7 is a cross-sectional view of a filament showing the radius (r) of the inscribed circle and the radius (R) of the circumscribed circle of the multilobe cross-sectional shape.

FIG. 8 is a cross sectional view of a triangular cross section yarn as a comparative example of the present invention.

FIG. 9 is an example of a spinneret shape for spinning a two-leaf cross section yarn as a comparative example of the present invention.

FIG. 10 is an example of a spinneret shape for spinning a yarn having a three-lobe cross-section according to an embodiment of the present invention.

FIG. 11 is an example of a die shape for spinning a yarn having a five-leaf cross-sectional shape according to an embodiment of the present invention.

FIG. 12 is an example of a die shape for spinning a yarn having an eight-leaf cross-sectional shape according to an embodiment of the present invention.

[Explanation of symbols]

 1 orifice 2 slit

Claims (6)

[Claims] 1. A screen gauze comprising a monofilament, wherein the warp and the weft include a monofilament having a multi-lobal cross-sectional shape. 2. A screen gauze composed of monofilaments, wherein at least 50% of one of the warp and weft monofilaments constituting the screen gauze has a multi-lobal cross-sectional shape and a cross-sectional shape of the monofilament. A screen gauze characterized in that monofilaments having a multi-leaf cross-sectional shape are evenly distributed on the screen gauze. 3. A screen gauze composed of monofilaments, wherein at least 25% of the monofilaments constituting the screen gauze have a multi-lobal cross-sectional shape and a mono-lobal cross-sectional shape. Screen gauze characterized in that monofilaments are evenly distributed on the screen gauze. 4. The screen gauze according to claim 1, wherein the multi-leaf cross-sectional shape is 3 leaves or more and 10 leaves or less. 5. The screen gauze according to claim 1, wherein the monofilament is made of polyester. 6. The screen gauze according to claim 1, wherein the monofilament contains a matting agent.