JP2021058879A - Wave type sieving mat and use thereof - Google Patents

Abstract

To provide a wave type sieving mat which can suppress clogging and can improve durability of even an object to be sorted which easily adheres.SOLUTION: As a screen mat 11 which is installed on a wave type sieving machine for sieving objects to be sorted while vibrating the same, a wave type sieving mat, which includes a core body 13 containing a cloth and a resin component, and a surface resin layer 12 which is laminated on a face on a screen upstream side (a side on which the object to be sorted is inputted) of the core body, and contains a silicone modified resin containing organosiloxane unit and which has a mesh by perforation, is manufactured. An average thickness of this screen mat may be 2.5 to 5 mm. Tear strength according to JIS K6252 of the screen mat may be 100 to 500 N/mm. In the screen mat 11, a back resin layer 14, which contains a silicone modified resin containing organosiloxane unit, may be laminated on a face on a screen downstream side of the core body.SELECTED DRAWING: Figure 4

Description

The present invention relates to a wave-type sieving mat for sieving lumps and powders such as ores, crushed stones, coke, and chemicals with a wave-type sieving machine, and uses thereof.

Masses and powders such as ore, crushed stone, coke, and chemicals are screened using a screen (net) to make the particle size uniform. Specifically, sieving is performed by placing a mass or powdery substance, which is an object to be screened (object to be sorted), on the upper surface of the screen and dropping it downward from the opening of the screen. Conventionally, a metal screen has been used as such a screen. However, in recent years, screens made of elastic material (rubber screens) have become the mainstream instead of metal screens because of their excellent life, noise problems, wear resistance, and ease of attachment to vibrating sieves. There is.

Further, as a sieving machine for sieving the lumps and powders and granules, a vibrating sieving machine for sieving by applying vibration to the screen is widely used, and among them, efficient sieving is possible. As a possible vibration sieving machine, a wave type sieving machine (jumping screen or jumping screen device) is known.

As shown in FIG. 1, the wave type sieving machine has a structure in which a plurality of rectangular screen mats 2 are arranged in parallel between the facing drive side plates 5. Each screen mat 2 is arranged in parallel along the longitudinal direction of the wave type sieving machine 1 in the width direction, and the screen mat 2 is a screen fixture on a flat bar 3 arranged between the adjacent screen mats 2. It is fixed at 4. The object to be sorted (processed object) 6 is thrown onto the screen mat 2 on the upstream side of the wave sieving machine 1, and is transferred toward the downstream side in the direction of the arrow in the drawing. A part of the object to be sorted (processed object) 6 is sieved by falling from the opening 2a of the screen mat 2 in the process of transfer.

FIG. 2 shows a partially cutaway enlarged view of FIG. 1 for explaining the detailed structure of FIG. 1. In the wave type sieving machine 1, both ends of one screen mat 2 are adjacent to each other, and the cross beam 7 It is arranged on the top, and both ends are pressed by metal flat bars 3 and fixed by screen fixtures 4 (bolts and nuts). Specifically, in one cross beam 7, one metal flat bar 3 fixes the ends of two adjacent screen mats 2 in an overlapping state. Further, the cross beams 7 arranged in order in the longitudinal direction of the wave type sieving machine 1 are alternately fastened to the inner drive side plate 5a and the outer drive side plate 5b. That is, in the cross beam 7 (adjacent cross beam) fixing both ends of one screen mat 2, one cross beam 7 is fastened to the inner drive side plate 5a, and the other cross beam 7 is on the outer side. It is fastened to the drive side plate 5b of. When the adjacent cross beams 7 move in the opposite phase in the horizontal direction (in the direction of the arrow in FIG. 2), the screen mat 2 fixed to the cross beams 7 repeats the movements of tension and loosening.

That is, when one screen mat 2 is pulled in conjunction with the movement of the drive side plate that moves in the opposite phase of the adjacent screen mat 2, the wave motion in which the other adjacent screen mat 2 loosens is repeated. FIG. 3 is a diagram for explaining such a repetitive operation of the screen mat 2, and more specifically, a schematic schematic cross-sectional view for explaining the repetitive operation of the screen mat 2 of FIG. 1 (along the width direction of the screen mat). (Cross section). That is, the loose screen mat 2 shown in FIG. 3 (a) is pulled by the drive side plate, and is pulled through the state of FIG. 3 (b) as shown in FIG. 3 (c). It reaches a state and repeats such a movement as a wave movement. In this wave motion, in the state of FIG. 3C in which the screen mat 2 is pulled, the object to be sorted 6 is violently flipped up in the direction of the arrow, and in the state of FIG. 3A in which the screen mat 2 is loosened, the screen is displayed. It falls on the mat 2 and collides violently. At the time of collision, the agglomeration of the object to be sorted 6 is crushed and dispersed. As described above, the wave type sieving machine (jumping screen) 1 can perform more efficient sieving by using this jumping in addition to the normal vibrating sieving. In particular, in a wave-type sieving machine, such a flip-up motion makes it easy even for a subject to be sorted with high adhesion, specifically, a subject to be sorted with a large amount of water, or a subject with high viscosity. In addition to being able to be crushed and dispersed, the opening is deformed and expanded by the wave motion of the screen mat, so clogging of the object to be sorted can be suppressed. Further, since the sieve surface is composed of a plurality of screen mats, only the damaged part can be replaced and maintenance is easy.

The following screen mats are known as screen mats for vibrating sieving machines.

In Japanese Patent Application Laid-Open No. 48-43264 (Patent Document 1), holes such as square holes, round holes, and polygonal holes are made in a metal plate or a plastic plate, and the ears thereof are bent to provide a support structure. A single elastic plate, a plastic film, and a reinforcing elastic plate lined with or inserted with a short fiber reinforcing elastic are placed on the supporting structure, which is prepared and perforated with a sieve mesh smaller than the mesh of the structure. A screen formed by bending the support structure so as to wrap the bent ear portion of the support structure is disclosed.

In Japanese Patent Application Laid-Open No. 48-43265 (Patent Document 2), a plastic film having a thickness of 2 mm or less or a woven fabric in which the overlapping portion of the warp and weft is fixed by an adhesive treatment, or a mixture of short fibers and the like. Disclosed is an elastic screen in which a mesh is punched and perforated in an elastic plate lined or embedded with a relatively thin and soft reinforcing material such as a reinforced polyurethane thin layer sheet reinforced by the above.

Japanese Patent Laying-Open No. 2019-141839 (Patent Document 3) describes a first rope, which is a plurality of strips arranged in parallel in the first direction at intervals, and the first rope on the first rope. It is formed by a second rope, which is a plurality of strips that are arranged and placed at intervals parallel to the second direction that intersects in one direction, and whose cross contact portions with the first rope are joined. In the screen, the first rope is embedded in the first body portion made of the first elastic material and the first body portion, and extends in the length direction to form a core wire. A second rope formed of a tension body, and the second rope is embedded in a second body portion made of a second elastic material, respectively, and extends in the length direction to form a core wire. A screen is disclosed in which the first elastic material and / or the pre-second elastic material is formed of a rope and contains a silicone-modified resin containing an organosiloxane unit.

Further, as a screen mat of a commercially available wave type sieving machine, a screen mat in which an opening is formed by perforating a urethane elastomer sheet is used.

Jitsukaisho 48-43264 Jitsukaisho 48-43265 Gazette Japanese Unexamined Patent Publication No. 2019-141839

However, Patent Documents 1 to 3 do not describe a wave type sieving machine.

Further, according to a study by the present inventors, the screen mats of Patent Documents 1 and 2 and commercially available screen mats have low non-adhesiveness even when used in a wave sieving machine, and the objects to be sorted are included. When the water content was too high or the viscosity was too high, the effect of the wave motion alone could not sufficiently prevent the adhesion. Therefore, there is a problem that the object to be sorted adheres (adhesively) to the surface of the screen mat and accumulates, and as the accumulation progresses, the screen is clogged. In addition, since the commercially available screen mat is a single layer of urethane elastomer sheet, the part fixed by the metal flat bar (the boundary between the flat bar and the mat) due to repeated pulling and loosening movements due to wave motion. ), A crack occurred, and early replacement was required.

Further, according to the examination by the present inventors, the screen mat of Patent Document 3 also has cracks like the commercially available screen mat, and early replacement is required. If the durability of the mat is improved by increasing the thickness of the screen mat, clogging is likely to occur, and there is a trade-off relationship between the durability of the mat and the suppression of clogging, and both are compatible. It is a difficult characteristic. As for the thickness of the mat, increasing the thickness to increase the mechanical strength can improve the durability of the mat, but increasing the strength to make the mat too rigid makes it difficult for the mat to bend into a wavy shape, resulting in unreasonable vibration. Exercise cracks the mat so that it breaks. Therefore, it is not easy to improve only the durability of the mat with a wave-type sieving machine that has a jumping function (repeated pulling and loosening movements due to wave motion), and it is even more difficult to achieve both suppression of clogging. Met.

Therefore, an object of the present invention is to provide a wave-type sieving mat and its use, which can suppress clogging and improve durability even for an object to be sorted that easily adheres.

As a result of diligent studies to achieve the above problems, the present inventors and others have found that the core body containing the cloth and the resin component and the surface of the core body on the upstream side of the screen (the side on which the object to be sorted is put or placed). By attaching a screen mat that is laminated and contains a surface resin layer containing a silicone-modified resin containing an organosiloxane unit and has a sieve mesh by perforation to a wave-type sieving machine, it is easy to adhere. The present invention has been completed by finding that clogging can be suppressed and durability can be improved even in a sorted product.

That is, the wave-type sieving mat of the present invention is a screen mat attached to a wave-type sieving machine for sieving the object to be sorted while vibrating, and includes a core body containing a cloth and a resin component. It is laminated on the surface of the core on the upstream side of the screen, contains a surface resin layer (surface non-adhesive layer) containing a silicone-modified resin containing an organosiloxane unit, and has a sieve mesh by perforation. The average thickness of this screen mat may be 2.5-5 mm. The tear strength of the screen mat according to JIS K6252 may be 100 to 500 N / mm. The screen mat may have a back surface resin layer containing a silicone-modified resin containing an organosiloxane unit laminated on the surface of the core body on the downstream side of the screen (the side through which the object to be sorted has passed). In the screen mat, the average thickness of the front surface resin layer may be equal to or more than the average thickness of the back surface resin layer, and the average thickness of the back surface resin layer may be 0.3 mm or more. The cloth may be a woven cloth having an average thickness of 0.2 mm or more. The average fineness of the threads constituting this woven fabric may be 1200 dtex or more. The yarn density of the yarns constituting this woven fabric may be 50 yarns / 5 cm or more. The core body may be a plurality of fabric layers in which an intermediate resin layer containing a silicone-modified resin containing an organosiloxane unit is interposed. The silicone-modified resin may be a polycarbonate-type polyurethane containing 3 to 15% by mass of an organosiloxane unit.

The present invention also includes a method of mounting the screen mat on a wave sieving machine to sift the objects to be sorted.

In the present invention, a core body containing a cloth and a resin component and a surface resin layer laminated on the surface of the core body on the upstream side of the screen and containing a silicone-modified resin containing an organosiloxane unit are included, and a sieve mesh is formed by perforation. Since the screen mat having the above is attached to the wave type sieving machine, clogging can be suppressed and the durability can be improved even if the object to be sorted easily adheres. In particular, by forming a specific back surface resin layer on the surface of the core body on the downstream side of the screen or forming the core body with a specific laminated body, the durability of the screen mat is further improved and clogging is suppressed. it can.

FIG. 1 is a schematic perspective view of a wave type sieving machine. FIG. 2 is a partially cutaway enlarged view for explaining the detailed structure of the wave type sieving machine of FIG. FIG. 3 is a schematic schematic cross-sectional view for explaining the repetitive operation of the screen mat 2 of FIG. FIG. 4 is a schematic view showing an example of the layer structure of the wave-type sieving mat of the present invention. FIG. 5 is a schematic view showing another example of the layer structure of the wave-type sieving mat of the present invention. FIG. 6 is a schematic view showing still another example of the layer structure of the wave-type sieving mat of the present invention. FIG. 7 is a schematic view showing another example of the layer structure of the wave-type sieving mat of the present invention. FIG. 8 is an array pattern diagram showing an example of the sieve mesh of the wave type sieving mat of the present invention. FIG. 9 is an array pattern diagram showing another example of the sieve mesh of the wave type sieving mat of the present invention. FIG. 10 is an array pattern diagram showing still another example of the mesh of the wave type sieving mat of the present invention. FIG. 11 is a plan view showing an example of the wave-type sieving mat of the present invention. FIG. 12 is an enlarged view of the mesh of the wave-type sieving mat of FIG. FIG. 13 is a plan view showing another example of the wave type sieving mat of the present invention. FIG. 14 is an enlarged view of the mesh of the wave-type sieving mat of FIG. FIG. 15 is a schematic view for explaining a method of measuring the tear strength of the sheet-like base material obtained in the examples. FIG. 16 is a plan view of a test piece and an iron plate used for measuring the strength of the opening of the sheet-like base material obtained in the examples. FIG. 17 is a schematic view showing a state in which the test piece is fixed in order to measure the strength of the opening of the sheet-like base material obtained in the examples. FIG. 18 is an array pattern diagram of the sieve mesh of the screen mat used in Examples 1 to 3, 7 to 8, 11 to 13 and Comparative Examples 1 to 2, 5 and 7. FIG. 19 is an array pattern diagram of the sieve mesh of the screen mat used in Examples 4 to 6, 9 to 10, 14 to 16 and Comparative Examples 3 to 4, 6 and 8. FIG. 20 is a schematic view for explaining a method of evaluating clogging in an embodiment. FIG. 21 is an array pattern diagram of the sieve mesh of the screen mat used in Examples 17 to 20 and Comparative Examples 9 to 10.

[Layer structure of wave-type sieving mat]
The wave-type sieving mat (screen mat) of the present invention is laminated on a core body containing a cloth and a resin component and a surface of the core body on the upstream side of the screen (the side before the object to be sorted passes through), and It suffices to have a layer structure including a surface resin layer containing a silicone-modified resin containing an organosiloxane unit. The layer structure of the wave-type sieving mat may be a structure having the core body and the surface resin layer, and an organoxane may be formed on the surface of the core body on the downstream side of the screen (the side through which the object to be sorted has passed). It may have a layer structure in which back surface resin layers containing a silicone-modified resin containing a siloxane unit are laminated, or the core body may have a layer structure including a plurality of fabric layers.

FIG. 4 is a schematic view showing an example of the wave-type sieving mat layer structure of the present invention, in which the core body 13, the surface resin layer 12 laminated on the surface of the core body 13 on the upstream side of the screen, and the above. It is formed of a back surface resin layer 14 laminated on the surface of the core body 13 on the downstream side of the screen. The surface resin layer 12 containing the silicone-modified resin can prevent the object to be sorted from adhering (adhering) to the surface of the screen mat and accumulating, and the combination with the core 13 can improve the mechanical strength of the mat. Therefore, cracks generated by the jumping function (repeated pulling and loosening movements due to wave motion) can be suppressed, and the durability of the screen mat can be improved. Further, since the back surface resin layer 14 is laminated on the back surface of the core body 13, it is possible to prevent lint and fluff generated by fraying of the fibers (threads) constituting the core body 13 from being mixed into the object to be sorted. The durability of the screen mat is further improved from the viewpoint of suppressing fraying of the core body 13. Further, since the back surface resin layer also contains the silicone-modified resin, clogging of the screen is suppressed. In this mat, the front surface resin layer 12 and the back surface resin layer 14 contain a silicone-modified resin in order to suppress clogging. Although the silicone-modified resin suppresses clogging, the silicone-modified resin does not. Since the adhesive strength is low, delamination caused by the jumping function is likely to occur, which is disadvantageous for the durability of the mat. As described above, from the viewpoint of the mechanical strength of the mat, there is a trade-off relationship between clogging suppression and mat durability, but in the screen mat of the present invention having a layered structure, not only the mechanical strength of the mat but also Although it is necessary to improve the interlayer adhesion, the resin component for suppressing clogging has a relationship of lowering the interlayer adhesion. Therefore, in the screen mat of the present invention, it is more difficult to achieve both clogging suppression and mat durability than the conventional screen mat having a single-layer structure. On the other hand, in the present invention, clogging can be suppressed and mat durability can be achieved at the same time by selecting the material constituting the core body and selecting the layer structure.

FIG. 5 is a schematic view showing another example of the layer structure of the wave-type sieving mat of the present invention, which is the same as the layer structure of the screen mat of FIG. 4 except that the back surface resin layer 14 is not formed. is there. In this layer structure as well, as in the screen mat of FIG. 4, it is possible to prevent the object to be sorted from adhering to and accumulating on the surface of the screen mat, and the durability of the screen mat can be improved, so that the thickness of the surface resin layer 12 can be increased. The mat durability with respect to cracks is equivalent to that of the mat of FIG. 4 due to the large adjustment. Since the back surface resin layer 14 is not laminated, the durability of the mat with respect to the fraying of the core body tends to be slightly lowered.

FIG. 6 is a schematic view showing still another example of the layer structure of the wave-type sieving mat of the present invention, and is a layer of the screen mat of FIG. 4 except that the core has a three-layer structure instead of a single-layer structure. It is the same as the structure. Specifically, the core body of FIG. 6 forms a three-layer structure in which the first cloth layer 13a and the second cloth layer 13c are laminated with the intermediate resin layer 13b interposed therebetween. Also in this layer structure, the surface resin layer 12 can prevent the object to be sorted from adhering to and accumulating on the screen mat surface, and the core body forms a three-layer structure, so that the durability is further improved. By forming the intermediate resin layer 13b with a silicone-modified resin containing an organosiloxane unit, clogging can also be suppressed. On the other hand, as the number of layers (number of laminated sheets) increases, the mat durability tends to decrease due to delamination. In the present invention, by combining a specific intermediate resin layer and a specific fabric layer, the mat durability with respect to delamination can be improved. Further, similarly to the screen mat of FIG. 4, the back surface resin layer 14 further improves the durability of the core body with respect to fraying.

FIG. 7 is a schematic view showing another example of the layer structure of the wave-type sieving mat of the present invention, which is the same as the layer structure of the screen mat of FIG. 6 except that the back surface resin layer 14 is not formed. is there. In this layered structure as well, as in the screen mat of FIG. 6, it is possible to prevent the object to be sorted from adhering to and accumulating on the surface of the screen mat, and the durability is also improved. Although the back surface resin layer 14 is not laminated, the thickness of the front surface resin layer 12 is greatly adjusted, so that the durability of the mat with respect to cracks is as excellent as that of the mat of FIG. The durability of the mat is slightly reduced.

The layer structure of the screen mat may be provided with the core body and the surface resin layer, and is further provided with the back surface resin layer from the viewpoint that fraying of the core body can be suppressed and the durability of the screen mat can be highly improved. Is preferable.

The core body may have a single-layer structure including a single cloth, or may have a laminated structure including a plurality of cloths. In the laminated structure, the number of fabrics is not particularly limited, and is 2 or more (for example, 2 to 10), preferably 2 to 5 (particularly 2 to 4), more preferably 2 to 3, and most preferably 2. A laminated structure is preferable from the viewpoint that the thickness and mechanical strength of the screen mat can be easily adjusted, and a single-layer structure is preferable from the viewpoint of improving the durability regarding delamination of the screen mat.

When the core body has a laminated structure, it is preferable that a middle layer resin layer is interposed between the cloth layers from the viewpoint of improving the interlayer adhesion.

The tear strength of the wave-type sieving mat of the present invention may be 100 N / mm or more, for example, 100 to 500 N / mm, preferably 150 to 480 N / mm, more preferably 200 to 450 N / mm, and most preferably 200 to 450 N / mm. It is 220 to 400 N / mm. If the tear strength is too small, the durability of the screen mat may decrease. On the contrary, if it is too large, it becomes difficult for the mat to bend in a wavy shape, and cracks may occur.

In the present application, the measurement can be performed by a method conforming to JIS K6252, and in detail, the measurement can be performed by the method described in Examples described later.

The average thickness of the wave-type sieving mat of the present invention is, for example, 1 to 7 mm, preferably 1.5 to 6 mm, and may be particularly 2.5 to 5 mm from the viewpoint of suppressing cracks in the belt. It is more preferably 2 to 5 mm, more preferably 2.5 to 4.5 mm, and most preferably 3 to 4 mm. If the thickness is too thin, the durability of the screen mat may decrease, and if it is too thick, the flexibility may decrease.

In the present application, the average thickness of the screen mat and each layer can be measured by a method of observing the cross section of the screen mat using a scanning electron microscope and calculating the average value of the thicknesses at three points.

[Mesh structure]
The wave-type sieving mat of the present invention has sieving meshes (plural openings) by perforation. In the present invention, since the sieving is not an opening (mesh) of a reticulated body formed by crossing a plurality of threads (ropes) but an opening by perforation, it has excellent durability and is mounted on a wave sieving machine. Even if it can be used for a long time.

The shape of each opening can be appropriately selected according to the type of the object to be sorted. For example, a polygonal shape such as a square shape, a rectangular shape, a rhombus shape, or a parallel quadrilateral shape; a perfect circle shape, a substantially circular shape, an elliptical shape, or a long shape. It may be a circular shape such as a circular shape. Among these shapes, from the viewpoint of productivity and the like, a circular shape such as a square shape, a rectangular shape, a square shape, or a perfect circular shape is preferable, and a square shape is particularly preferable.

The opening diameter of the opening can be appropriately selected according to the type of the object to be sorted, and can be selected from, for example, a range of about 2 to 35 mm. When the shape of the opening is square or perfect, the opening diameter (the length of one side of the square or the diameter of the circle) is preferably 3 to 30 mm, more preferably 5 to 25 mm. When the shape of the opening is rectangular, oval or elliptical, the major axis (the length of the long side of the rectangle) is, for example, 5 to 35 mm, preferably 10 to 25 mm, and more preferably 12 to 12 to the major axis of the opening diameter. It is 20 mm, and the minor axis (the length of the short side of the rectangle) is, for example, 2 to 10 mm, preferably 2 to 5 mm.

The arrangement pattern of the sieve mesh is not particularly limited as long as it is regularly arranged. For example, as shown in FIG. 8, a pattern structure in which square openings are regularly arranged at equal intervals in the vertical and horizontal directions. , As shown in FIG. 9, the square openings are arranged at equal intervals in the horizontal direction (length direction of the screen mat) and alternately staggered at equal intervals in the vertical direction (width direction of the screen mat). Staggered pattern structure (horizontal chidori structure), as shown in FIG. 10, square openings are arranged at equal intervals in the vertical direction, and the chidori (staggered) pattern is alternately staggered in the horizontal direction. The structure (vertical chidori type structure) and the like can be mentioned.

On the surface of the wave-type sieving mat, the area ratio occupied by the openings (the ratio of the total area of the openings) may be 25% or more, for example, 25 to 75%, preferably 30 to 70%, more preferably. Is 35 to 65%, most preferably 40 to 60%. If the area of the opening is too large, the efficiency of sieving the object to be sorted may decrease, and conversely, if it is too small, the durability of the screen mat may decrease.

The planar shape of the wave-type sieving mat is usually rectangular, and as shown in FIG. 1, the width direction of the mat is parallel to the longitudinal direction of the wave-type sieving machine, and a plurality of wave-type sieving mats are arranged in parallel. It is attached to the machine.

An example of the wave-type sieving mat of the present invention is shown in FIG. 11. As shown in FIG. 12, the screen mat 20 has a square opening 21 formed in a vertical chidori pattern, and the upper end in the width direction. Holes 22 for mounting and fixing for mounting on the cross beam are perforated at equal intervals in the portion and the lower end portion. In FIG. 11, the opening is partially omitted.

Another example of the wave-type sieving mat of the present invention is shown in FIG. 13. As shown in FIG. 14, in the screen mat 30, the oval-shaped opening 31 has an oval opening 31 along the long axis along the width direction of the screen mat. The upper end and the lower end in the width direction are formed by arranging them at equal intervals in the vertical and horizontal directions, and holes 32 for mounting and fixing for mounting on the cross beam are perforated at equal intervals. Also in FIG. 13, the opening is partially omitted.

[Surface resin layer]
In the present invention, since the surface resin layer contains a silicone-modified resin containing an organosiloxane unit, it is possible to prevent the object to be sorted from adhering to the screen mat and suppress clogging.

In the silicone-modified resin contained in the surface resin layer, the base resin is modified with a silicone component, and more specifically, the organosiloxane unit (silicone unit) is copolymerized and incorporated in the molecule of the base resin. The resin (base resin unit) can improve the adhesion to the core body, and the silicone component can suppress the adhesion of the object to be sorted.

The organosiloxane unit is represented by the formula: -Si (-R) _2- O- (in the formula, the group R is a substituent), and the substituent represented by the group R includes an alkyl group, an aryl group, and the like. Cycloalkyl groups and the like can be mentioned. _{Examples of the alkyl group include C 1-12} alkyl groups such as methyl, ethyl, propyl, butyl, hexyl, octyl and decyl. _{Aryl groups include, for example, C 6-20} aryl groups such as phenyl, methylphenyl (or trill), dimethylphenyl (or xsilyl), naphthyl and the like. Examples of the cycloalkyl group include C _5-14 cycloalkyl groups such as cyclopentyl, cyclohexyl and methylcyclohexyl. These substituents can be used alone or in combination of two or more. Of these substituents, a C _{1-3 alkyl group such as a methyl group and a C 6-12} aryl group such as a phenyl group are widely used.

The form of introducing the organosiloxane unit is not particularly limited as long as it is bonded (copolymerized) in the base resin, and may be introduced into the main chain or the side chain. The introduction method can be selected according to the type of base resin, and is based on a (poly) organosiloxane monomer having an ethylenically unsaturated bond (vinyl group, etc.) or a reactive group (hydroxyl group, amino group, carboxyl group, etc.). It may be introduced by reacting (polymerizing) with a resin or a monomer thereof. The form of copolymerization is not particularly limited, and may be any of random copolymerization, block copolymerization, and graft copolymerization. Organosiloxane units are often derived from polyorganosiloxane diols.

The molecular weight of the skeleton (polyorganosiloxane diol) into which the organosiloxane unit has been introduced is, for example, 100 to 50,000, preferably 500 to 10000.

The ratio of the organosiloxane unit can be selected from the range of about 1 to 50% by mass with respect to the entire silicone-modified resin, for example, 2 to 30% by mass, preferably 3 to 25% by mass, and more preferably 5 to 20% by mass. Most preferably, it is 6 to 18% by mass. In particular, the proportion of the organosiloxane unit is 3 to 15% by mass, preferably 4 to 4 to the total amount of the silicone-modified resin, from the viewpoint of improving the bonding strength with the core while maintaining the non-adhesiveness to the material to be sorted. It may be 12% by mass, more preferably 5 to 10% by mass, and most preferably 6 to 9% by mass. If the proportion of the organosiloxane unit is too small, the non-adhesiveness to the object to be sorted may decrease, and conversely, if it is too large, the adhesion to the core may decrease.

The silicone-modified resin may be a thermoplastic resin or a thermoplastic elastomer. In the case of a thermoplastic resin, examples of the base resin include polyolefins, (meth) acrylic resins, polyesters, polyacetals, polycarbonates, polyurethanes, and polyimides. In the case of thermoplastic elastomers, examples of the base resin include polyolefin elastomers, polyester elastomers, polyamide elastomers, polyurethane elastomers and the like. These base resins can be used alone or in combination of two or more.

Among these base resins, a thermoplastic resin or a thermoplastic elastomer is preferable, and a polyurethane or a polyurethane elastomer is particularly preferable, from the viewpoint of handleability and flexibility.

The polyurethane (or polyurethane elastomer) may be a polyurethane obtained by reacting a polyol or a polyisocyanate.

Examples of the polyols include polyester polyols (including polycaprolactones), polyether polyols, polyether ester polyols, polycarbonate polyols, polyesteramide polyols, acrylic polymer polyols and the like. These polyols can be used alone or in combination of two or more. Among these polyols, polyether polyols (poly C _2-4 alkylene glycol such as polyethylene glycol and polytetramethylene glycol ether) and polycarbonate polyols (ethylene glycol and 1, _{Reaction products of C 2-6} alkanediol such as 4-butanediol and _{di C 1-4} alkyl carbonate such as dimethyl carbonate _{or di C 6-12} aryl carbonate such as diphenyl carbonate) are preferred.

Polyisocyanates include, for example, aliphatic diisocyanates such as aliphatic polyisocyanates [propylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMDI), lysine diisocyanate (LDI), etc. , 1,6,11-Undecantryisocyanate Methyloctane, 1,3,6-hexamethylenetriisocyanate and other aliphatic triisocyanates], alicyclic polyisocyanate [cyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI) , Hydrocyclic xylylene diisocyanate, alicyclic diisocyanate such as hydrogenated bis (isocyanatophenyl) methane, alicyclic triisocyanate such as bicycloheptane triisocyanate], aromatic polyisocyanate [phenylenediocyanate, tolylene diisocyanate ( TDI), xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), naphthalenediocyanate (NDI), bis (isocyanatophenyl) methane (MDI), toluidine diisocyanate (TODI), 1,3-bis (isocyanato) Phenyl) Aromatic diisocyanates such as propane] and the like are included.

These polyisocyanates are multimers [dimers, trimers (polyisocyanates having an isocyanurate ring), tetramers, etc.], adducts, modified products (biuret modified products, alohanate modified products, urea modified products, etc.). Etc.), or a urethane oligomer having a plurality of isocyanate groups.

These polyisocyanates can be used alone or in combination of two or more. Among these polyisocyanates, aliphatic diisocyanates such as HDI, alicyclic diisocyanates such as IPDI, aromatic aliphatic diisocyanates such as XDI, and aromatic diisocyanates such as MDI and TDI are widely used and are highly versatile. Aromatic diisocyanates are particularly preferred.

Among these polyurethanes, polyether type polyurethane and polycarbonate type polyurethane are preferable from the viewpoint of excellent water resistance and chemical resistance, have excellent non-adhesiveness to the object to be sorted, can suppress clogging, and adhere to the core body. Polycarbonate type polyurethane is particularly preferable because it can improve the properties.

When the silicone-modified resin is a silicone-modified polyurethane, the surface resin layer may further contain a curing agent. As the curing agent, conventional curing agents such as polyisocyanates, polyols, and polyamines can be used and can be selected according to the type of polyurethane, but polyisocyanates are preferable from the viewpoint of reactivity and the like. As the polyisocyanates, the polyisocyanates can be used. Among the polyisocyanates, aromatic diisocyanates are preferable as the curing agent from the viewpoint of stable reactivity.

The ratio of the curing agent is, for example, 1 to 50 parts by mass, preferably 2 to 25 parts by mass, and more preferably 5 to 10 parts by mass with respect to 100 parts by mass of the silicone-modified polyurethane.

As the silicone-modified resin of the surface resin layer, an elastomer-type polyurethane silicone-modified resin (silicone-modified polyurethane elastomer) that is not used in combination with a curing agent is preferable, and an elastomer-type polycarbonate-type polyurethane silicone-modified resin (silicone-modified polycarbonate-type polyurethane) is preferable. Elastomer) is particularly preferred.

The surface resin layer may further contain other resin components such as rubber, elastomer, and non-silicone modified polyurethane. The ratio of the other resin components is 30 parts by mass or less, preferably 0.1 to 20 parts by mass, and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the silicone-modified resin (particularly silicone-modified polyurethane).

The surface resin layer may contain conventional additives such as chain extenders, stabilizers (weather resistant stabilizers, antioxidants, heat stabilizers, light stabilizers, etc.), fillers, plasticizers, lubricants, etc. Good. These additives can be used alone or in combination of two or more. The ratio of the additive is 30 parts by mass or less, preferably 0.1 to 20 parts by mass, and more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the silicone-modified resin (particularly silicone-modified polyurethane).

The average thickness of the surface resin layer is, for example, 0.3 to 7 mm, preferably 0.5 to 5 mm, more preferably 1 to 4 mm, and most preferably 1.5 to 3.5 mm. If the thickness of the surface resin layer is too thin, the non-adhesiveness may decrease, and conversely, if it is too thick, the flexibility may decrease.

[Core body]
The core body contains the cloth and the resin component, and the cloth and the resin component may form independent layers, but usually, at least a cloth layer in which the resin component is impregnated between the fibers inside the cloth is formed. Includes.

As the cloth (or canvas), a cloth commonly used for the core body can be used, and examples thereof include woven cloth and knitted cloth. Of these fabrics, woven fabrics are preferable because they are excellent in strength and productivity.

The woven structure (woven structure) of the woven fabric may be, for example, a plain weave, a twill weave (oblique weave), a satin weave (satin weave), or the like. Among these woven structures, a plain weave may be used from the viewpoint of excellent balance of strength and the like, and a twill weave and a satin weave structure may be used from the viewpoint of adhesion to the surface resin layer.

In the woven fabric, the yarn density (average value of warp yarn density and weft yarn density) may be 30 yarns / 5 cm or more (particularly 50 yarns / 5 cm or more), for example, 30 to 150 yarns / 5 cm, preferably 30 to 150 yarns / 5 cm. It is 45 to 100 lines / 5 cm, more preferably 50 to 80 lines / 5 cm, and most preferably 53 to 60 lines / 5 cm. In applications where a high degree of belt durability is required, the density may be, for example, 53 to 65 lines / 5 cm, particularly 55 to 62 lines / 5 cm. If the thread density is too low, the durability of the screen mat may decrease.

The fibers constituting the fabric may be short fibers, but from the viewpoint of strength, spun yarns (spun yarns) obtained by twisting long fibers and short fibers are preferable. Further, the long fibers may be monofilament yarns or multifilament yarns. Of these, multifilament yarn is preferable from the viewpoint of durability of the screen mat.

As the fiber, fibers of various materials can be used, for example, polyester fiber (polyalkylene allylate fiber such as polyethylene terephthalate and polyethylene naphthalate), polyamide fiber (aliphatic polyamide fiber such as polyamide 6 and polyamide 66, aramid fiber, etc.). , Cellulous fibers such as cotton and rayon may be used. _{Of these, poly C 2-4} alkylene allylate fibers such as polyethylene terephthalate (PET) are preferable from the viewpoint of excellent balance of strength and flexibility.

The average fineness of the fibers (in the case of woven fabric, the average value of the average fineness of the warp yarn and the average fineness of the weft yarn) may be 1200 dtex or more in the case of monofilament yarn or multifilament yarn, for example, 1200 to 3000 dtex, preferably 1200 dtex. It is 1300 to 2500 dtex, more preferably 1500 to 2000 dtex, and most preferably 1600 to 1800 dtex. For applications that require a high degree of belt durability, the average fineness of the warp threads is, for example, 1500-3000 dtex, preferably 1600-2800 dtex, more preferably 1800-2500 dtex, more preferably 2000-2400 dtex, most preferably 2100-2300 dtex. There may be. If the fineness is too low, the durability of the screen mat may decrease.

The average thickness of the fabrics (the average thickness of each fabric when a plurality of fabrics are combined) may be 0.2 mm or more, for example, 0.2 to 2.0 mm, preferably 0.23 to 1.0 mm, and further. It is preferably 0.25 to 0.7 mm, more preferably 0.28 to 0.65 mm, and most preferably 0.4 to 0.6 mm. In applications where a high degree of belt durability is required, the average thickness may be, for example, 0.5 to 1.0 mm, preferably 0.6 to 0.9 mm, and even more preferably 0.8 to 0.85 mm. Good. If the thickness is too thin, the durability of the screen mat may decrease.

As the cloth layer, the resin component to be impregnated in the cloth is the same as the silicone-modified resin contained in the surface resin layer (that is, the same as the base resin of the silicone-modified resin) in that the adhesion to the surface resin layer can be improved. Or the same type of resin) is preferable. Therefore, when the silicone-modified resin is silicone-modified polyurethane, polyurethane is preferable as the resin component of the core body. As the polyurethane, the polyurethane exemplified as the base resin of the silicone-modified resin can be used alone or in combination of two or more. Of the polyurethanes, a polyether type polyurethane or a polycarbonate type polyurethane is preferable, and a polyether type polyurethane is particularly preferable, for the same reason as the surface resin layer. The core polyurethane may also be combined with the curing agent exemplified in the section on the surface resin layer. As the core polyurethane, a prepolymer type polyurethane used in combination with a curing agent is preferable to an elastomer type polyurethane. The proportion of the curing agent and the preferred embodiment are the same as those of the curing agent of the surface resin layer. In the present invention, by forming the resin component of the fabric layer with such polyurethane, clogging can be suppressed and the interlayer adhesion can be improved.

In the cloth layer, the ratio of the resin component is, for example, 10 to 100 parts by mass, preferably 10 to 50 parts by mass with respect to 100 parts by mass of the cloth. If the proportion of the resin component is too small, the strength may be insufficient and the adhesion to the surface adhesive layer may be lowered, and if it is too large, the flexibility of the screen mat may be lowered.

The core body may include a cloth layer in which the cloth is impregnated with a resin component, and may include a cloth layer that does not contain a resin component. However, from the viewpoint of improving interlayer adhesion, all the cloth layers are used. It is preferable that the cloth is a cloth layer in which the cloth is impregnated with a resin component.

When forming a laminate with a plurality of fabric layers, an intermediate resin layer may be interposed between the fabric layers. The intermediate resin layer is not particularly limited as long as the fabric layers can be bonded to each other, and a conventional adhesive or adhesive can be used, and a resin of the same type as the resin component to be impregnated in the fabric (for example, polyurethane) may be used. However, it is preferable to use a silicone-modified resin containing an organosiloxane unit from the viewpoint that the adhesion between the fabric layers can be improved and the clogging of the screen can be suppressed. This silicone-modified resin can be selected from the silicone-modified resins containing the organosiloxane unit described in the section of the surface resin layer, including the preferred embodiment. The intermediate resin layer may further contain other resin components and conventional additives exemplified in the section of the surface resin layer in the same ratio.

The average thickness of the intermediate resin layers (the average thickness of each intermediate resin layer when a plurality of intermediate resin layers are combined) is, for example, 0.5 to 5 mm, preferably 1 to 3 mm, and more preferably 1.5 to 2.5 mm. is there. If the thickness of the intermediate resin layer is too thin, the effect of improving durability may decrease, and conversely, if it is too thick, the flexibility may decrease.

In the core body, the number of laminated fabrics (number of plies) can be appropriately selected according to the mechanical strength and flexibility required for the durability of the target screen mat, but about 1 to 5 plies are widely used. 1 to 3 plies are preferable, 1 to 2 plies are more preferable, and 1 ply is more preferable from the viewpoint of improving mat durability and economy regarding delamination.

[Back resin layer]
In the wave-type sieving mat of the present invention, a back surface resin layer may be formed on the surface to be sorted and the surface on the downstream side of the screen of the core body. By forming the back surface resin layer, the durability of the belt can be improved, and in particular, the fraying of the core body due to long-term use can be suppressed.

The back surface resin layer is not particularly limited as long as it can be adhered to the core body, and a conventional adhesive or adhesive can be used, and a resin of the same type as the resin component impregnated in the cloth of the core body layer (for example, polyurethane) can be used. However, it is preferable to use a silicone-modified resin containing an organosiloxane unit because it can improve the adhesion to the core and suppress clogging of the screen. This silicone-modified resin can be selected from the silicone-modified resins containing the organosiloxane unit described in the section of the surface resin layer, including the preferred embodiment. The back surface resin layer may further contain other resin components and conventional additives exemplified in the section of the front surface resin layer in the same ratio.

The average thickness of the back surface resin layer may be 0.3 mm or more, for example, 0.3 to 7 mm, preferably 0.5 to 6 mm, more preferably 1 to 5 mm, more preferably 2 to 4 mm, and most preferably 2. .5 to 3.5 mm.

The average thickness of the front surface resin layer may be equal to or greater than the average thickness of the back surface resin layer, and the average thickness of the front surface resin layer is, for example, 1.5 to 10 times, preferably 2 to 10 times the average thickness of the back surface resin layer. It is 8 times, more preferably 3 to 7 times, and most preferably 4 to 6 times. If the thickness of the surface resin layer is too small, the object to be sorted may easily adhere.

[Manufacturing method of wave-type sieving mat]
The wave-type sieving mat of the present invention can be produced by a conventional method. For example, a laminating step of laminating a surface resin layer precursor on one surface of a core precursor to obtain a mat base material precursor. A method of hot-pressing the obtained mat base material precursor to integrate the obtained mat base material precursor and a perforation step of perforating the obtained mat base material to form an opening is preferable.

As a method for preparing the core precursor used in the laminating step, a conventional method can be used, for example, a method of impregnating a liquid composition containing a resin component and a curing agent with a cloth (Japanese Patent Laid-Open No. 11-29212). Etc.). Examples of the solvent of the liquid composition include hydrocarbons (for example, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as toluene and xylene), halogenated hydrocarbons (chloroform, dichloromethane and the like), and the like. Ethers (chain ethers such as diethyl ether, cyclic ethers such as dioxane and tetrahydrofuran), ketones (acetone, methyl ethyl ketone, etc.), esters (methyl acetate, ethyl acetate, etc.), amides (eg, formamide, N, N) − Dimethylformamide and the like), nitriles (eg, acetonitrile and the like), sulfoxides (eg, dimethyl sulfoxide and the like) and the like. These organic solvents can be used alone or as a mixed solvent. Among these solvents, hydrocarbons, ethers, ketones and the like are widely used. The concentration of the resin component in the liquid composition is, for example, 5 to 50% by mass, preferably 10 to 30% by mass, and more preferably 15 to 20% by mass.

After the immersion, it may be heated and dried. The heating temperature is, for example, 60 to 200 ° C, preferably 80 to 160 ° C, and more preferably 100 to 140 ° C. The heating time may be, for example, 1 minute or more, for example, 1 to 30 minutes, preferably 3 to 10 minutes.

Further, when a plurality of fabrics are laminated as the core, a laminate of the fabric impregnated with the liquid composition and the sheet-like intermediate resin layer precursor may be used as the core precursor.

When the back surface resin layer is laminated on the other surface of the core body, the back surface resin layer precursor may be laminated on the other surface of the core body precursor in the laminating step.

The method of laminating the front surface resin layer precursor and the back surface resin layer precursor can be selected according to the type of the precursor, and may be a coating method of coating on the core body precursor. From the point of view, a method of laminating the sheet-like precursor on the core precursor is preferable.

In the hot pressing step, the heating temperature can be selected according to the type of resin component, but may be, for example, 100 ° C. or higher, preferably 100 to 200 ° C., and more preferably 120 to 180 ° C. The applied pressure is, for example, 0.1 MPa or more, preferably 0.1 to 0.6 MPa, and more preferably 0.2 to 0.5 MPa. The hot pressing time may be, for example, 10 seconds or more, for example, 1 to 20 minutes, preferably about 3 to 10 minutes.

The hot pressing step is not limited to the step of hot pressing the mat base material precursors all at once, and may be divided into a plurality of times and hot pressed. For example, each time each layer precursor is laminated. , May be hot pressed.

As a method for forming an opening in the mat base material in the drilling step, a conventional method can be used, and a method for forming the opening by punching drilling, a cutting plotter, or the like can be used.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[Details of materials used]
(Sheet-like precursor for forming the front surface resin layer and the back surface resin layer)
Elastic body 1: Silicone-modified polycarbonate type thermoplastic polyurethane elastomer [“Resamine PS” manufactured by Dainichiseika Kogyo Co., Ltd., silicone content 8% by mass], thickness 0.4 to 4.2 mm
Elastic body 2: Silicone-modified polycarbonate type thermoplastic polyurethane elastomer [“Resamine PS” manufactured by Dainichiseika Kogyo Co., Ltd., silicone content 16% by mass], thickness 0.4 to 2.5 mm
Elastic body 3: Silicone-modified polyether type thermoplastic polyurethane elastomer [“Resamine PS” manufactured by Dainichi Seika Kogyo Co., Ltd., silicone content 8% by mass], thickness 0.4 to 2.5 mm
Elastic body 4: Silicone-modified polyether type thermoplastic polyurethane elastomer [“Resamine PS” manufactured by Dainichi Seika Kogyo Co., Ltd., silicone content 16% by mass], thickness 0.4 to 2.5 mm
Elastic body 5: Polycarbonate type thermoplastic polyurethane elastomer [silicone unmodified product, "Milactran XN-2001" manufactured by Nippon Miractran Co., Ltd.], thickness 0.4 to 2.5 mm
Elastic body 6: Polyether type thermoplastic polyurethane elastomer [silicone unmodified product, "Milactran E385" manufactured by Nippon Miractran Co., Ltd.], thickness 0.4 to 2.8 mm.

(Material for forming the core)
Plain weave fabric 1: [War yarn: Polyester (PET) multifilament (fineness 1670 dtex, number of twists 1, yarn density: 57/5 cm), Weft: Polyester (PET) multifilament (fineness 1670 dtex, number of twists 1, yarn) Density: 52 pieces / 5 cm)], thickness 0.58 mm
Plain weave fabric 2: [War yarn: Polyester (PET) multifilament (fineness 1100 dtex, number of twists 2, yarn density: 65/5 cm), Weft: Polyester (PET) multifilament (fineness 1000 dtex, number of twists 1, yarn) Density: 50 pieces / 5 cm)], thickness 0.82 mm
Resin component: Polyether type thermoplastic polyurethane resin (reactant of polytetramethylene ether glycol and MDI)
Solvent: A mixed solvent of methyl ethyl ketone, cyclohexane and tetrahydrofuran (methyl ethyl ketone / cyclohexane / THF = 15/45/40 (mass ratio))
Hardener: Polyisocyanate composition.

[Adhesion treatment of core body]
A plain weave cloth 1 or 2 is immersed in a liquid composition consisting of a resin component, a curing agent and a solvent for 0.5 minutes to be taken out, and then heated at 120 ° C. for 5 minutes to dry to remove the solvent to remove the core. A precursor was obtained.

[Preparation of sheet-like base material (1 ply product)]
With the configurations shown in Tables 1 and 2, the sheet-like precursor made of elastic body 1 or 6 and the core precursor are laminated, and heat-pressed at 150 ° C. and 0.3 MPa for 5 minutes using a press machine to laminate the sheet-like material. After melting the precursor, it was cooled and solidified to prepare a laminated body as a sheet-like base material.

[Physical characteristics test of sheet-like substrate]
(Tear strength)
The sheet-shaped substrates 1 to 10 shown in Tables 1 and 2 were measured using a universal material testing machine (“Strograph T” manufactured by Toyo Seiki Co., Ltd.) in accordance with JIS K6252. A trauser-shaped test piece 40 (rectangular test piece having a 10 cm cut 40a in the length direction from the midpoint of the upper end) shown in FIG. 15 (a) was prepared, and as shown in FIG. 15 (b), the cut 40a One end and the other end were grasped by the gripping tools 41 and 42, and the force required to tear at a speed of 50 mm / min was measured starting from the notch. The base materials 1 to 4 and 6 to 10 including the core were tested in the warp direction. The test result was an average value of n = 3.

(Strength of opening)
For the sheet-shaped substrates 1 to 10 shown in Tables 1 and 2, test pieces having a length of 100 mm and a width of 50 mm were collected. As shown in FIG. 16, an oblong opening 50a having a length of 12 mm and a width of 22 mm was punched out so that the center was 16 mm from the lower end of the test piece 50 and centered on the left and right. In addition, iron plates 51 and 52 having openings were also used for measuring the strength. The dimensions of the test piece 50 and the iron plates 51 and 52 are as follows.

Specimen 50: 100 mm x 50 mm x 5 mmt, hole diameter: 12 mm x 22 mm, the center of the hole is 16 mm from the lower end Iron plate 51: 50 mm x 50 mm x 5 mmt, hole diameter: φ12 mm, the center of the hole is 25 mm from the upper end Iron plate 52: 100 mm x 50 mm x 5 mm t, hole diameter: φ12 mm, center of hole is 25 mm from the top

As shown in FIG. 17, the test piece 50 is sandwiched between the iron plate 51 and the iron plate 52, the bolt 53 of M10 is passed through the opening and fixed with the nut 54, and the upper part of the test piece 50 and the lower part of the iron plate 52 are air chucked. Fixed with. Using an autograph (manufactured by Shimadzu Corporation), the maximum strength when the bolt tears the opening when the test piece is pulled upward was measured at an ambient temperature of 23 ° C. and a speed of 50 mm / min. The test result was an average value of n = 2.

(Adhesive strength between layers)
The adhesive strength between the surface resin layer and the fabric layer was measured by a method according to JIS K6322.

The obtained evaluation results are shown in Tables 1 and 2.

As is clear from the results in Table 1, the base material 1 having the 1-ply core body layer has the tear strength and the opening, although the sheet thickness is thin, as opposed to the base material 5 having no core body. The strength was excellent. Although the sheet thickness was the same as that of the base material 5, the base material 3 having the 1-ply core layer was significantly excellent in tear strength and opening strength.

Further, the base materials 2 to 4 are examples in which the sheet thickness is changed with respect to the base material 1 (a mode in which the core body is 1 ply), but in the sheet thickness (2.8 to 5.0 mm) in this range, the sheet thickness is changed. The tear strength and the strength of the opening were excellent. Further, in the base materials 1 to 4, sufficient adhesive strength was obtained between the surface resin layer and the core body (fabric layer).

Further, even in the base material 6 which has the same sheet thickness as the base material 2 but does not have the back surface resin layer, the tear strength, the strength of the opening, and the layers between the base materials 2 are the same as those of the base material 2. Adhesive strength was obtained.

As is clear from the results in Table 2, the mechanical strength of the base material 2 using the plain weave cloth 1 is higher than that of the plain weave cloth 1 (the total fineness of the warp threads is large and the thread density is also high). In the base material 7 changed to the plain weave cloth 2, the tear strength, the strength of the opening, and the adhesive strength between the layers were improved as compared with the base material 2.

Next, with respect to the base material 2, the back surface resin layer is changed to an elastic body 6 which is an unmodified silicone material, and the front surface resin layer and the back surface resin layer are made of an unmodified silicone material. In the base material 9 changed to the elastic body 6, the tear strength and the strength of the opening were the same as those of the base material 2.

The adhesive strength between the layers of the base material 8 was the same as that of the base material 2, but in the base material 9 in which the surface resin layer was an unmodified silicone, the layer between the surface resin layer and the core body was more than the base material 2. Adhesive strength has increased. Even in the mode of the base material 10 (thickness equivalent to the base material 3) in which the thickness of the sheet is larger than that of the base material 9, the tear strength and the strength of the opening are the same as those of the base material 3, and the adhesive strength between the layers is high. It became larger than the base material 3.

Of the above base materials 1 to 10, screen mats were prepared for the base materials 1 to 2 and 8 to 10 by the following method, and non-adhesiveness evaluation and clogging evaluation were performed.

[Making a screen mat]
Examples 1 and 4
Using a base material 1 having a length of 2500 mm and a width of 1500 mm and using a large-format flatbed cutting plotter (manufactured by Mimaki Engineering Co., Ltd.), length 21 mm x width 21 mm (Example 1), length 7 mm x width 7 mm (Example 4). ) Was formed to prepare a screen mat. As for the arrangement of the openings, the screen mat of Example 1 is the pattern shown in FIG. 18, and the screen pattern of Example 4 is the pattern shown in FIG.

Examples 2 and 5
A screen mat of Example 2 was prepared in the same manner as in Example 1 except that the base material 2 was used, and a screen mat of Example 5 was prepared in the same manner as in Example 4.

Examples 3 and 6
A screen mat of Example 3 was prepared in the same manner as in Example 1 except that the base material 8 was used, and a screen mat of Example 6 was prepared in the same manner as in Example 4.

Comparative Examples 1 and 3
Using a base material 9 having a length of 2500 mm and a width of 1500 mm and using a large-format flatbed cutting plotter (manufactured by Mimaki Engineering Co., Ltd.), length 21 mm x width 21 mm (Comparative Example 1), length 7 mm x width 7 mm (Comparative Example 3) ) Was formed to prepare a screen mat. As for the arrangement of the openings, the screen mat of Comparative Example 1 is the pattern shown in FIG. 18, and the screen pattern of Comparative Example 3 is the pattern shown in FIG.

Comparative Examples 2 and 4
A screen mat of Comparative Example 2 was prepared in the same manner as in Comparative Example 1 except that the base material 10 was used, and a screen mat of Comparative Example 4 was prepared in the same manner as in Comparative Example 3.

[Non-adhesiveness evaluation of screen mat]
The screen mats obtained in Examples 1 to 6 and Comparative Examples 1 to 4 are cut into predetermined dimensions (width 215 mm, length 330 mm) to form a test piece, which is horizontally movable (rectangular table). The test piece is fixed on the top so that the length direction of the test piece is parallel to the length direction of the table. Next, an adhesive tape (width 50 mm, length 250 mm) is placed in the center of the surface (upper surface of the screen) of the test piece so that the length direction of the adhesive tape is parallel to the length direction of the table and the test piece. Press with a roller to attach. Further, the load cell is fixed on one side in the length direction of the table, and one end of the adhesive tape on the side opposite to the side where the load cell is fixed and the tip of the string fastened to the load cell are gripped and fixed with a clip. .. The table is moved in the length direction at 300 mm / min toward the direction away from the load cell, the adhesive tape is peeled off from the surface of the test piece in the 180 degree direction, and the peeling force is measured. The peeling force was an average value excluding the peak value at the initial stage of peeling.

[Evaluation of clogging of screen mat]
The screen mats prepared in Examples 1 to 6 and Comparative Examples 1 to 4 were used to evaluate clogging. Each screen mat is cut to a predetermined size (width 215 mm, length 330 mm) and installed in a metal frame. Next, as shown in FIG. 20, the screen mat 61 fixed with the metal frame is fixed to the L-shaped angle 62 with an inclination angle of 20 °. As a sample, a mixture of gravel and crushed stone 63 [grain size: 1 to 5 mm (Examples 4 to 6 and Comparative Examples 3 to 4), 1 to 15 mm (Examples 1 to 3 and Comparative Examples 1 to 2), moisture. Amount: 10%] was placed in the vicinity of the center position on the screen mat 61, the screen was vibrated by the vibrating device 64 for 60 seconds, and the weight of the sample passed through the opening was measured. As an index of clogging, as shown in the following formula, the passage rate was calculated from the weight of the sample that passed through the opening of the screen mat with respect to the total weight of the sample placed on the screen mat.

Passage rate (%) = [weight passed through the opening (g) / weight placed on the screen mat (g)] × 100.

The evaluation results are shown in Table 3.

As is clear from the results in Table 3, in Example 1 (base material 1) and Example 2 (base material 2) in which the elastic body 1 (silicone-modified polyurethane) was used for the front surface resin layer and the back surface resin layer, comparative examples were used. The non-adhesiveness was high because the peeling force in the non-adhesiveness evaluation was smaller than that of 1 (base material 9) and Comparative Example 2 (base material 10). In addition, it was difficult to clog because the passing rate of the clogging evaluation was high.

Although the front surface resin layer is an elastic body 1, in Example 3 (base material 8) in which the elastic body 6 is used for the back surface resin layer, the non-adhesiveness is equivalent to that of Examples 1 and 2. In the clogging evaluation, the transmittance decreased and clogging became more likely.

Further, Example 4 (base material 1), Example 5 (base material 2), Example 6 (base material 8), Comparative Example 3 (base material 9), and Comparative Example 4 (base material 9) in a screen mat having a small opening. The same tendency was observed in the case of material 10).

[Preparation of sheet-like base material (2-ply product)]
With the configuration shown in Table 4, the sheet-shaped precursor made of elastic body 1 or 6 and the core precursor were laminated and heat-pressed at 150 ° C. and 0.3 MPa for 5 minutes using a press machine to obtain a sheet-shaped laminated precursor. Was melted and then cooled to solidify to prepare a laminate to be a sheet-like substrate 11 to 13.

[Physical characteristics test of sheet-like substrate]
(Tear strength)
With respect to the sheet-shaped base materials 11 to 13 shown in Table 4, the tear strength was measured in the same manner as the base materials 1 to 4 and 6 to 10.

(Strength of opening)
For the sheet-shaped base materials 11 to 13 shown in Table 4, the strength of the openings was measured in the same manner as in the base materials 1 to 10.

(Adhesive strength between layers)
The adhesive strength between the surface resin layer and the first fabric layer was measured by a method according to JIS K6322.

The obtained evaluation results are shown in Table 4. For comparison, the evaluation results of the base material 3 are also shown.

As is clear from the results in Table 4, when compared with the same sheet thickness (about 4.0 mm), the core body (fabric layer) is the same as that of the base material 3 in which the core body (fabric layer) is 1 ply. In the two-ply base materials 11 to 13, the tear strength and the strength of the opening were increased.

The base material 11 uses the elastic body 1 (silicone-modified polyurethane) for the front surface resin layer, the intermediate resin layer, and the back surface resin layer, whereas the base material 12 has the intermediate resin layer and the back surface resin layer made of unmodified silicone. The base material changed to the elastic body 6, the base material 13 is a base material in which the front surface resin layer, the intermediate resin layer, and the back surface resin layer are changed to the elastic body 6 which is an unmodified silicone product. Regarding the tear strength and the strength of the opening, the base materials 11 to 13 were the same. The adhesive strength between the surface resin layer and the first fabric layer was the same as that of the base material 12 in the base material 12, but in the base material 13 in which the surface resin layer was an unmodified silicone, the base material 11 and The adhesive strength was higher than that of 12.

For the above base materials 11 to 13, screen mats were prepared by the following methods, and non-adhesiveness evaluation and clogging evaluation were performed.

[Making a screen mat]
Examples 7 and 9
A screen mat of Example 7 was prepared in the same manner as in Example 1 except that the base material 11 was used, and a screen mat of Example 9 was prepared in the same manner as in Example 4.

Examples 8 and 10
A screen mat of Example 8 was prepared in the same manner as in Example 1 except that the base material 12 was used, and a screen mat of Example 10 was prepared in the same manner as in Example 4.

Comparative Examples 5 and 6
A screen mat of Comparative Example 5 was prepared in the same manner as in Comparative Example 1 except that the base material 13 was used, and a screen mat of Comparative Example 6 was prepared in the same manner as in Comparative Example 3.

[Non-adhesiveness evaluation of screen mat]
The non-adhesiveness of the screen mats prepared in Examples 7 to 10 and Comparative Examples 5 to 6 was evaluated in the same manner as the screen mats prepared in Examples 1 to 6 and Comparative Examples 1 to 4.

[Evaluation of clogging of screen mat]
The screen mats prepared in Examples 7 to 10 and Comparative Examples 5 to 6 were evaluated for clogging in the same manner as the screen mats prepared in Examples 1 to 6 and Comparative Examples 1 to 4.

The evaluation results are shown in Table 5.

As is clear from the results in Table 5, in Example 7 (base material 11) in which the elastic body 1 (silicone-modified polyurethane) was used for the front surface resin layer, the intermediate resin layer, and the back surface resin layer, the surface resin layer and the intermediate resin layer were used. Compared with Comparative Example 5 (base material 13) in which the elastic body 6 (polyurethane not modified with silicone) was used for the back surface resin layer, the non-adhesiveness was high because the peeling force in the non-adhesiveness evaluation was small. In addition, it was difficult to clog because the passing rate of the clogging evaluation was high.

The front surface resin layer is an elastic body 1, but in Example 8 (base material 12) in which the elastic body 6 is used for the intermediate resin layer and the back surface resin layer, the non-adhesiveness is equivalent to that of Example 7. However, in the clogging evaluation, the transmittance decreased and clogging became easy.

Further, the same tendency was observed in the cases of Example 9 (base material 11), Example 10 (base material 12), and Comparative Example 6 (base material 13) in the screen mat having a small opening.

From the above results, it was clarified that the use of silicone-modified polyurethane imparts non-adhesiveness to the screen mat as in the case of the 1-ply product, and as a result, it is effective in suppressing clogging.

[Making a screen mat]
Comparative Examples 7 and 11-13
Examples except that the base material 2 using the elastic body 1 for the front surface resin layer and the back surface resin layer was used with the base material in which the materials of the front surface resin layer and the back surface resin layer were changed to the elastic bodies 2 to 5. A screen mat was prepared in the same manner as in 2.

Comparative Example 8 and Examples 14-16
Examples except that the base material 2 using the elastic body 1 for the front surface resin layer and the back surface resin layer was used with the base material in which the materials of the front surface resin layer and the back surface resin layer were changed to the elastic bodies 2 to 5. A screen mat was prepared in the same manner as in 5.

[Physical characteristics test of sheet-like substrate]
With respect to the obtained sheet-like base material, the adhesive strength between the layers was measured in the same manner as in the base material 2.

[Non-adhesiveness evaluation of screen mat]
The non-adhesiveness of the screen mats prepared in Examples 11 to 16 and Comparative Examples 7 to 8 was evaluated in the same manner as the screen mats prepared in Examples 1 to 6 and Comparative Examples 1 to 4.

[Evaluation of clogging of screen mat]
The screen mats prepared in Examples 11 to 16 and Comparative Examples 7 to 8 were evaluated for clogging in the same manner as the screen mats prepared in Examples 1 to 6 and Comparative Examples 1 to 4.

The evaluation results are shown in Table 6.

As is clear from the results in Table 6, Examples 2 and 11 to 13 in which the front surface resin layer and the back surface resin layer were formed of elastic bodies 1 to 4 made of silicone-modified polyurethane (silicone content 8% by mass, 16% by mass). Since the peeling force in the non-adhesiveness evaluation was small, the non-adhesiveness was high, and the passing rate of the clogging evaluation was high, so that clogging was difficult. On the other hand, in Comparative Examples 1 and 7 in which the front surface resin layer and the back surface resin layer were formed of elastic bodies 5 to 6 made of unmodified silicone (silicone content 0% by mass), the peeling force in the non-adhesiveness evaluation was high. Due to its large size, non-adhesiveness was low, and the passing rate of clogging evaluation was low, so clogging was easy.

Further, comparing the difference in the silicone content of the silicone-modified polyurethane forming the surface resin layer, as the silicone content decreased, the non-adhesiveness and the clogging property decreased, and the adhesive strength between the layers improved. In the screen mats of Comparative Examples 1 and 7 having a silicone content of 0% by mass, the clogging property (transmittance) was at a practically unacceptable level. Further, considering the balance between non-adhesiveness (clogging) and adhesiveness, when the silicone content was 16% by mass, the adhesive strength was slightly insufficient, so 8% by mass was the most excellent. Further, regarding the structure of polyurethane in the silicone-modified polyurethane forming the surface resin layer, the polycarbonate type was slightly superior to the polyether type in terms of both non-adhesiveness (clogging) and adhesiveness. That is, the screen mat of Example 2 in which the surface resin layer was formed of the polycarbonate-type silicone-modified polyurethane having a silicone content of 8% by mass had the best balance.

Further, the same tendency was observed in the cases of Examples 5 and 14 to 16 and Comparative Examples 3 and 8 in the screen mat having a small opening.

Examples 17-20 and Comparative Examples 9-10
Using a base material 2 having a width of 1915 mm and a length of 249 mm, a base material 5, a base material 6, a base material 7, a base material 9, and a base material 11, a large-format flatbed cutting plotter (manufactured by Mimaki Engineering Co., Ltd.) was used. A screen mat was produced by forming an opening having an array pattern shape shown in FIG. 21.

For the durability test, a wave sieving machine (manufactured by Eura Techno Co., Ltd.) having a path of 6000 mm in which 24 screen mats were arranged in parallel in the width direction of the screen mat was used. The screen mat is fixed to a metal flat bar (width 45 mm) arranged between the adjacent screen mats with a screen fixture, and one flat bar is used to connect the ends of two adjacent screen mats to each other. Were fixed to one cross beam in an overlapping state. The material to be sorted was put on the screen mat, and the screen mat was sieved by repeating the wave motion of the screen mat. Sieving is performed up to 12 months, and if an abnormality occurs in the screen mat (crack in the perforated part, crack in the mat, fraying of the core, delamination, extreme clogging, etc.) before reaching 12 months. At that point, it was judged that it had reached the end of its life, and the test was discontinued. If no abnormality occurred in the screen mat even after sieving for 12 months, it was judged that the durability was excellent.

The test conditions are as shown in 1) to 4) below.

1) Aperture ratio of screen effective part (part not fixed by flat bar): 33%
2) Object to be sorted: Sintered ore (particle size composition: 10%: 10 mm or less, 30%: 10 to 5 mm, 60%: 5 mm or more)
3) Moisture content: 3 to 6% (sprinkle water on the screen as a measure against dust)
4) Processing amount: 100 tons / month

The evaluation results are shown in Table 7.

In Table 7, the passing amount and the clogging property were evaluated according to the following criteria.

Passage amount: The amount of material to be sorted that passes on the screen per hour in a path of 6000 mm. The more easily clogged the screen mat is used, the less the material to be sorted will be deposited on the screen and the supply will be stagnant, resulting in less passage.

Clogging property: It was considered good if the object to be sorted was clogged and there was no need to unravel it with a jig or the like.

As is clear from the results in Table 7, even if the elastic body 1 (silicone-modified polyurethane) is used for the surface resin layer, in Comparative Example 9 of the screen mat made of the base material 5 having no core body, the clogging property (clogging property) ( The amount of passage) was good, but the bent part broke and the life was reached in 3 months. On the other hand, in Examples 17 to 19 having a core body, the clogging property (passage amount) was good, and no abnormality was observed even after 12 months had passed.

Example 20 is an example of a screen mat made of a base material 6 having no back surface resin layer. The clogging property (passage amount) was as good as that of the other examples, but after 12 months had passed. The core body was frayed.

Comparative Example 10 is an example of a screen mat made of a base material 9 that does not use an elastic body 6 (polyurethane unmodified with silicone). No abnormality was observed even after 12 months, but clogging was likely to occur. Due to the lack of passage, sieving had to be supplemented with a jig to unravel the material to be sorted.

The wave-type sieving mat of the present invention can be used as a screen mat attached to a wave-type sieving machine for sieving lumps and powders such as ores, crushed stones, coke, and chemicals. It is useful as a screen mat to be attached to a wave-type sieving machine for sieving a subject to be sorted having a large amount of water and a subject having high adhesion such as a subject having a high viscosity.

1 ... Wave type sieving machine 2, 11 ... Screen mat 12 ... Front surface resin layer 13 ... Core body 14 ... Back surface resin layer

Claims (9)

A screen mat attached to a wave-type sieving machine for sieving an object to be sorted while vibrating, which is laminated on a core body containing a cloth and a resin component and the surface of the core body on the upstream side of the screen. A wave-type sieving mat that includes a surface resin layer containing a silicone-modified resin containing an organosiloxane unit and has a sieve mesh by perforation. The wave-type sieving mat according to claim 1, wherein the average thickness is 2.5 to 5 mm. The wave-type sieving mat according to claim 1 or 2, wherein the tear strength according to JIS K6252 is 100 to 500 N / mm. The wave-type sieving mat according to any one of claims 1 to 3, wherein a back surface resin layer containing a silicone-modified resin containing an organosiloxane unit is laminated on the surface of the core body on the downstream side of the screen. The wave-type sieving mat according to claim 4, wherein the average thickness of the front surface resin layer is equal to or greater than the average thickness of the back surface resin layer, and the average thickness of the back surface resin layer is 0.3 mm or more. Any one of claims 1 to 5, wherein the fabric is a woven fabric having an average thickness of 0.2 mm or more, the average fineness of the yarns constituting the woven fabric is 1200 dtex or more, and the yarn density is 50 yarns / 5 cm or more. Wave type sieving mat described in. The wave-type sieving mat according to any one of claims 1 to 6, wherein the core is a plurality of fabric layers in which an intermediate resin layer containing a silicone-modified resin containing an organosiloxane unit is interposed. The wave-type sieving mat according to any one of claims 1 to 7, wherein the silicone-modified resin is a polycarbonate-type polyurethane containing 3 to 15% by mass of an organosiloxane unit. A method of sieving an object to be sorted by mounting the screen mat according to any one of claims 1 to 8 on a wave sieving machine.

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