JPS6315398B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial application field This invention relates to an endless belt for papermaking, and particularly relates to an extended nip press in the press part of the papermaking process.
Press, hereinafter abbreviated as ENP. ) is useful as a belt. (B) Prior Art In the press part of the papermaking process, there are roll presses and ENP as press methods, and ENP has become popular in recent years because it has various advantages. To put it simply, ENP is a wet paper sandwiched between two sheets of felt. One side of the paper is held down with a rotating roll, and the other side is pressurized with a pressure shoe via an ENP belt to dehydrate it. This is a press to do. Conventional belts for ENP have been disclosed in British Patent Publication No. 2106555A and British Patent Publication No. 2106557A, etc., but these belts are endless by weaving a flat base fabric made of multiple weaves of synthetic fiber threads. It has a configuration in which an elastic material layer is formed on one side. The elastic material layer surface of this belt is slid on the pressure shoe, and the other exposed surface of the base fabric is brought into contact with the felt. However, in this conventional method, a flat base fabric made of multiple weavings of synthetic fiber threads is weaved together to create an endless pattern, so the woven structure and thread density of the spliced parts are uneven compared to other parts. Therefore, there is a problem in terms of strength, and there is also a problem in that weaving joint marks are likely to occur on the paper. (C) Purpose of the Invention The object of the present invention is to provide an endless belt for papermaking that can be used for a longer period of time than conventional ENP belts and does not generate weave joint marks on paper. (d) Structure of the invention Thus, according to the present invention, there is provided a belt in which one side of the base fabric is covered with an elastic material layer, the base fabric is woven in an endless manner with a bag weave, and the base fabric is covered with the elastic material layer. On the exposed side of the base fabric that is not covered, the plane that touches the apex of the bend in the yarn in the running direction of the belt is at a lower position than the plane that touches the apex of the bend in the thread in the direction that crosses the running direction of the belt. A woven endless belt for papermaking is provided. In order to make an endless belt by splicing a multi-layered flat base fabric as in the past, in order to increase the strength of the spliced part, 'threads in the running direction of the belt' are used.
It is necessary to create a structure that has a sufficiently large bend in order to sufficiently entangle the two. In other words, the weave has a structure in which the ``threads in the running direction of the belt'' have large bends throughout the belt (so-called weft multiple weave). On the other hand, since great strength is not required in the direction intersecting the running direction of the belt, there is no need to increase the bending in that direction. Therefore, the bending point of the ``thread in the running direction of the belt'' is located outside of the ``thread in the direction that intersects with the running direction of the belt.'' By the way, the 'thread in the running direction of the belt' is the thread that requires the most strength in the belt, but in the above structure, the 'thread in the running direction of the belt' comes into direct contact with the felt, and the strength is the highest. It will wear out. In other words,
In conventional endless belts made by weaving multiple layers of flat base fabric, it is difficult to avoid the fact that the threads that require the most strength wear out the most quickly. Can not. In addition to considering the above, the inventor of the present invention has conducted various studies and found that it is possible to make the base fabric a multiple bag weave.
It has been discovered that the above problems can be solved. That is, in this invention, since the base fabric is a bag weave, the conventional problem of strength at the weaving joint is completely solved. In addition, since there is no weaving splice, there is no need to increase the bending of the ``threads in the running direction of the belt'' as described above, and even if the same horizontal multiple weaving method as before is used, the ``threads in the running direction of the belt'' The structure is such that the bending point of the belt can be avoided from being located outside of the ``thread in the direction that intersects the running direction of the belt.'' On the contrary, 'thread in the running direction of the belt'
Even a weaving method (so-called warp multiple weave) in which the bending point of the belt is located inside the ``threads in the direction intersecting the running direction of the belt'' is possible. As a result, the wear of the ``threads in the running direction of the belt'' that are subject to the most force can be avoided by protecting the ``threads in the direction that crosses the running direction of the belt,'' which can significantly improve the durability of the belt. was discovered. That is, the base fabric used in this invention is the same as the conventional one in that it needs to be multi-woven and endless, but in addition, it can be weaved repeatedly like the conventional base fabric to have an endless shape. It is woven in an endless manner by bag weaving, and on the exposed side of the base fabric where the base fabric is not covered with an elastic material layer, the plane that touches the apex of the bending of the yarn in the running direction of the belt is It is characterized by being woven in a multiple weave position lower than the plane that touches the apex of the bending of the yarn in the direction that intersects the running direction of the belt. Therefore, the endless belt for papermaking of the present invention does not have a spliced part where the applied force is uneven, and therefore
It has the advantage of being extremely superior in strength and other aspects to endless belts. In manufacturing the bag weave base fabric according to the present invention, both so-called horizontal multiple weave and warp multiple weave can be used. but,
In view of the durability of this belt, it is preferable to use vertical multiple weave to form a bag weave. To explain bag weaving using warp multiple weaving more specifically, the threads in the direction intersecting the running direction of the belt are used as the warp (warp threads) of the loom, and the threads in the running direction of the belt are used as the weft threads (horizontal threads) of the loom. do. In this case, it is usually preferable to use a multiple weave, that is, a double weave to a quadruple weave, in which the threads in the running direction of the belt have two to four layers. In case of bag weaving, a middle board is used to make the warp density of both bag selvedges the same as other parts. When the woven base fabric is cut to a predetermined length, it becomes an endless base fabric belt because the fabric is woven using a bag weave. This base fabric belt is stretched under a predetermined tension in a finishing machine and heat set with hot air, infrared rays, or a heat cylinder. The tension applied to the yarn in the running direction of the belt is, for example, the width of the base fabric belt 1
The weight should be 4 to 7 kg per cm. For example, heat treatment
The heat treatment time for the base fabric belt is 30 seconds at 130-170℃.
Do this for 120 seconds. The threads for weaving the base fabric are, for example, 6-nylon, 6,6-nylon, 6,10-nylon, 12-nylon,
Preferably, monofilament or multifilament synthetic fiber yarns such as nylon, aromatic polyamide, or polyester are used. In the case of double weaving, the threads in the belt running direction of the thread layer on the exposed side of the base fabric should be monofilament with a diameter of 0.25 mm or more and 0.6 mm or less in order to meet the required strength and thickness, and should be made of an elastic material. The yarn in the running direction of the belt in the yarn layer on the layer side is a multifilament textured yarn or nylon of 1000 denier or more and 4000 denier or less, in order to achieve a weaving balance with the monofilament diameter mentioned above and the specified air permeability. spun yarn or polyester spun yarn, and the number of threads in each layer is 5 per cm to obtain the required thickness, strength and air permeability.
It is preferable that the number be at least 30 books and no more than 30 books. The most preferred form of multiple weave in this invention is triple weave. In this case, the threads in the belt running direction of the thread layer on the exposed surface side of the base fabric are of the same type as in the case of the double weave, and The threads in the running direction of the belt in the thread layer have good adhesion to the elastic material.
Either monofilament with a diameter of 0.25 mm or more and 0.6 mm or less, or multifilament with a diameter of 450 denier or more and 3500 denier or less, or a twisted yarn thereof, and the yarn of the intermediate yarn layer sandwiched between these two yarn layers is as described above. In the case of double weave, the yarn layer on the elastic material layer side is the same type as the yarn in the running direction of the belt, and the number of yarns in each layer is 1 cm.
Preferably, the number is 5 or more and 12 or less. In the case of quadruple weave, the threads in the running direction of the belt in the thread layer on the exposed side of the base fabric and the next thread layer are the same as the threads in the running direction of the belt in the thread layer on the exposed side of the base fabric in the triple weave. The threads in the running direction of the belt in the third thread layer from the exposed surface of the base fabric and the thread layer on the elastic material layer side are the same as those in the intermediate thread layer and the thread layer on the elastic material layer side in the case of the triple weave, respectively. It is preferable that the threads are of the same type as those in the running direction of the belt, and that the number of threads in each layer is the same as in the case of the triple weave. In order to obtain the necessary thickness, abrasion resistance, and belt stability, the threads in the direction crossing the running direction of the belt should be monofilament with a diameter of 0.3 mm or more and 0.7 mm or less, and the number of threads should be 12 or more per 1 cm. Preferably, the number is 24 or less. As the elastic material of the elastic material layer, it is preferable to use, for example, polyurethane, acrylonitrile butadiene, ethylene acrylic copolymer, fluorinated hydrocarbon, epichlorohydrin rubber, polyester elastomer, soft vinyl chloride, or thermoplastic urethane. The surface of the elastic material layer is preferably roughened using a grindstone or the like in order to improve the adhesion of lubricating oil. It is preferable to form an abrasion-resistant coating, a low friction coefficient coating, or a waterproof coating on the surface of the yarn exposed on the exposed surface of the base fabric. Examples of such coatings include coatings of fluororesin, silicone resin, fluorine-containing epoxy resin, and urethane resin. In the base fabric belt manufactured in this manner, the plane that is in contact with the apex of the bending of the thread in the direction intersecting the running direction of the belt is located at a higher position than the plane that is in contact with the apex of the bending of the thread in the direction of running of the belt, It is preferable from the viewpoint of strength and abrasion that the distance between them is 0.11 mm or more and 0.33 mm or less, and the air permeability (JIS L 1079-1976) is 20 cm ³ / cm ² /
From the viewpoint of forming the elastic resin layer, it is preferable that the velocity is not less than sec and not more than 100 cm ³ /cm ² /sec. ^In the above, if the velocity is less than 20cm ³ /cm ² /sec, it is difficult for air in ^the elastic material layer to escape;
If it exceeds sec, the elastic material will pass through the base fabric, which is not preferable. The elastic material layer is formed, for example, by applying an elastic material onto one side of the base fabric belt, and grinding it to a predetermined thickness after hardening. At this time, it is good that the elastic material is impregnated into the inside of the base fabric, but care must be taken because it must not penetrate to other surfaces. One way to achieve this is to use an elastic material that takes a short curing time. Another method is to use textured yarn in the yarn layer of the base fabric, as described above, to thereby control the permeation of the elastic material.
Spun yarn may be used in place of the textured yarn, but since spun yarn is fluffy and tends to generate air bubbles within the elastic material, in that case it is preferable to perform a fluffing treatment. After the elastic material is hardened, it is ground to roughen the surface and have a predetermined thickness, thereby forming an elastic material layer. For the grindstone used for grinding and roughening the surface of the elastic material layer, it is appropriate that the material is green silicon carbide (JIS: GC) and the average diameter is 840 to 500μ (JIS: particle size: 24). When this is used, the surface roughness will be approximately Rmax 20μm. Furthermore, it is preferable that a wear-resistant coating, a low friction coefficient coating, or a waterproof coating is then formed on the threads exposed on the exposed surface of the base fabric by a spraying method or a dipping method. (E) Embodiment 1 shown in FIG. 1 is an embodiment of the endless belt for papermaking of the present invention. The width is 4.76m, and the outer side is the base fabric exposed side 2.
The inner side is a urethane rubber layer 3. FIG. 2 is a diagram showing a part of the AA' cross section of FIG. 1. The thickness T ₁ of endless belt 1 is 2.7 mm,
The thickness T ₂ of the base fabric 4 is 1.76 mm, and the thickness T ₃ of the urethane rubber layer 3 is 2.2 mm. The threads in the running direction α of the belt are the side thread layers x ₁ , x ₂ ... on the exposed surface of the base fabric, and the intermediate thread layers y ₁ , y ₂ ...
... and the urethane rubber layer side thread layer z ₁ , z ₂ ... and the thread in the direction β that intersects the running direction of the belt.
k ₁ , k ₂ ... are the threads x ₁ , x ₂ ... in the running direction of the belt
It passes outside of z ₁ , z ₂ .... On the side of the base fabric exposed surface 2, a virtual plane P touches the bending vertices of _{the yarns k 1 ,} k _{2 .} The distance H between the virtual planes Q that are in contact with the vertices of the bend is 0.21 mm. FIG. 3 shows the structure of the base fabric 4 in detail. In the figure (A), the threads k ₁ , k ₂ . . . in the direction crossing the running direction of the belt are nylon monofilaments with a diameter of 0.47 mm, and are set as warp threads in a loom. Among the yarns in the running direction of the belt, the upper layer yarns x ₁ and x ₂ ... in Figure 3 A are nylon monofilament with a diameter of 0.37 mm, and the middle layer yarns y ₁ and y ₂ ... are 1600 denier nylon multifilament. textured yarn, the underlying yarn z ₁ , z ₂ ... is the diameter
0.37mm nylon monofilaments, these are set as weft threads on the loom. The warp and weft yarns set in this way are woven together based on the organization chart shown in FIG. 3C. Therefore, during weaving, the warp becomes a thread in the direction β that intersects the running direction of the endless belt 1, and the weft becomes a thread in the belt running direction α. Tables 1-1 to 1-3 show the characteristics of the above base fabric 4 and the base fabrics with the same structure as the above base fabric 4 but with different types of threads.
Shown below. FIGS. 4 to 6 show other embodiments of multiple weave of the base fabric. FIG. 4 shows another embodiment of a triple weave different from that shown in FIG. 3. In this embodiment _{, the threads x 1 ,} x ₂ . . . and z ₁ , z ₂ . Thread k in the direction crossing the running direction ₁
is characterized in that only yarns x ₁ and x ₂ are woven together, and yarn k ₃ in the direction intersecting the running direction of the belt is woven together only yarns z ₁ , z _{2 .} . . . Since the bending angles of the yarns _k1 and _k3 are large and the contact area with the felt can be widened, it has excellent abrasion resistance. In this example, the threads x ₁ , x ₂ ... of the thread layer on the exposed surface side of the base fabric in the running direction of the belt are nylon monofilament with a diameter of 0.43 mm, the thread y ₁ , which becomes the intermediate thread layer,
y ₂ ... is a textured yarn of 1600 denier nylon multifilament, and z ₁ , z ₂ ..., which will be the urethane rubber side layer, are nylon monofilament with a diameter of 0.43 mm. The threads k ₁ , k ₂ ... that intersect with the running direction of the belt are nylon monofilaments with a diameter of 0.52 mm. The characteristics of the base fabric of this example, such as thickness and basis weight, are as shown in Table 2. When an endless belt was made using the base fabric of this example, the length etc. of the belt were the same as those shown in FIGS. 1 and 2. The base fabric of this example is woven according to the organization chart shown in FIG. 4C. Figure 5 shows the threads x ₁ , x ₂ . . . in the running direction of the belt.
y ₁ , y ₂ ... z ₁ , z ₂ ... w ₁ , w ₂ ... indicates a four-layer weave base fabric. In this example, the threads x ₁ , x ₂ ... of the thread layer on the exposed surface side of the base fabric in the running direction of the belt are nylon monofilament with a diameter of 0.35 mm, and the threads y ₁ , y ₂ ... of the first intermediate thread layer are nylon monofilament with a diameter of 0.35 mm. are nylon monofilament with a diameter of 0.35 mm, and the threads w ₁ , w ₂ of the second intermediate thread layer are...
is 1600 denier polyester spun yarn, and the threads z ₁ , z ₂ on the urethane rubber layer side are nylon monofilament with a diameter of 0.35 mm. The threads k ₁ , k ₂ . . . in the direction crossing the running direction of the belt are nylon monofilaments with a diameter of 0.47 mm. The characteristics of the base fabric of this example, such as thickness and basis weight, are as shown in Table 3. The belt length etc. when manufacturing an endless belt using the base fabric of this example are shown in Figure 1~
It is the same as that shown in FIG. The base fabric of this example is woven based on the organization chart shown in FIG. 5C. FIG. 6 shows a double-woven base fabric having two layers of yarns x and y in the running direction of the belt. In this example, the yarn x of the yarn layer on the exposed surface side of the base fabric in the running direction of the belt is
The textured yarn is 1600 denier nylon multifilament, and the yarn y in the yarn layer on the urethane rubber side is nylon monofilament with a diameter of 0.52 mm. Threads k ₁ , k ₂ in the direction that intersects the running direction of the belt
is a nylon monofilament with a diameter of 0.52 mm. The characteristics of the base fabric of this example, such as thickness and basis weight, are as shown in Table 4. The length of the belt when an endless belt for papermaking is manufactured using the base fabric of this example is as follows:
This is the same as that shown in FIGS. 1 and 2. The base fabric of this example is woven based on the organization chart shown in FIG. 6C.

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[Table] The corn has been subjected to a sintering process.

[Table] (F) Effects of the Invention The endless belt for papermaking of the present invention has the above-described structure, and the base fabric is endlessly woven with a bag weave, and the base fabric is not covered with an elastic material layer. On the exposed side, the plane in contact with the apex of the bend in the yarn in the running direction of the belt is at a lower position than the plane in contact with the apex of the bend in the thread in the direction crossing the running direction of the belt, that is, in the running direction of the belt. If the structure is such that the threads in the direction that intersects with the running direction of the belt are located on the outside of the threads, the threads in the running direction of the belt will be protected by the threads that intersect with the running direction of the belt, thereby preventing contact with the felt. As a result, the threads are worn from the outside, but the threads that cross the running direction of the belt, which are not subject to high tension, are mainly worn, and the threads that are subject to high tension, that are in the running direction of the belt, are hardly worn. As a result, the belt has a long service life and has the advantage of being able to stably squeeze out moisture from the wet paper over a long period of time. By the way, a belt bending test (based on JIS K 6323) was carried out using the endless belt test piece shown in Figure 1, 30 mm wide x 500 mm long, with a reciprocating bending stroke of 130 mm, a reciprocating bending speed of 180 times/min, an environmental temperature of 25°C to 35°C, and a test load of 100 kg. ), it was found that with the conventional product, the threads in the running direction of the test piece were worn out so much after about 500,000 cycles that it became unusable, but the product of the present invention could not be used in the running direction of the test piece until about 1,000,000 cycles. There was almost no wear on the threads. In other words, the product of the present invention is estimated to have a lifespan more than twice that of the conventional product. Furthermore, since the fabric is endlessly woven by bag weaving, there are no weaving joints where the texture, thickness, and air permeability of the base fabric are uneven, and there is no problem with paper marks.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the endless belt for papermaking according to the present invention, and FIG.
Partially enlarged view of cross section A', Figure 3 A, B, and C are the first
A cross-sectional structural diagram of the base fabric used in the endless belt shown in the figure, an explanatory cross-sectional diagram of the weaving method, and an organization chart, Part 4
6 to 6 are views corresponding to FIG. 3 of other embodiments of the base fabric, respectively. 1...Endless belt for paper making, 2...Exposed surface of base fabric, 3...Urethane rubber layer, 4...Base fabric, α
...Belt running direction, β...Direction intersecting the belt running direction, x ₁ , x ₂ ... y ₁ , y ₂ ... z ₁ , z ₂ ...
...Threads in the running direction of the belt, k ₁ , k ₂ ...Threads in the direction that intersects with the running direction of the belt.

Claims (1)

[Scope of Claims] 1. A belt in which one side of a base fabric is covered with an elastic material layer, the base fabric is endlessly woven with a bag weave, and the base fabric is exposed without being covered with the elastic material layer. The belt is characterized by being woven in a multi-layered weave in which the plane that touches the apex of the bend in the yarn in the running direction of the belt is at a lower position than the plane that touches the apex of the bend in the thread in the direction that crosses the running direction of the belt. Endless belt for paper making. 2 Claims in which the distance between the plane that is in contact with the apex of the bend in the thread in the running direction of the belt and the plane that is in contact with the apex of the bend in the thread in the direction that intersects with the running direction of the belt is 0.11 mm or more and 0.33 mm or less The endless belt for papermaking described in item 1. 3 The multiple weave of the base fabric is such that the threads in the running direction of the belt are 3
Claims 1 and 2 are triple weave layers.
The endless belt for papermaking described in any of the above. 4 Among the threads in the running direction of the three-layer belt, the threads in the layer closest to the elastic material layer have a diameter of 0.25 mm or more.
Nylon monofilament or polyester monofilament of 0.6 mm or less, the next nearest layer is textured yarn of nylon multifilament or spun yarn of nylon or polyester of 1000 denier or more and 4000 denier or less, and the furthest layer The endless thread for paper making according to claim 3, wherein the thread is nylon monofilament or polyester monofilament with a diameter of 0.25 mm or more and 0.6 mm or less, and the number of threads in each layer is 5 or more and 12 or less per 1 cm.
belt. 5. The method according to claims 1 to 4, wherein the threads in the direction crossing the running direction of the belt are nylon monofilament with a diameter of 0.3 to 0.7 mm, and the number of threads is 12 or more and 24 or less per 1 cm. The endless belt for papermaking described in any of the above. 6. Claims 1 to 5, wherein the elastic material layer is formed by applying urethane elastomer to one side of a woven base fabric and impregnating the other side of the base fabric to an extent that it does not bleed. An endless belt for papermaking according to any of the above. 7. Claims 1 to 6 in which an abrasion-resistant coating is formed on the surface of the yarn exposed on the exposed surface of the base fabric.
The endless belt for papermaking described in any of the above.