JP2007204862A - Belt for papermaking machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt for papermaking machine having excellent physical properties such as crack resistance, abrasion resistance, hair crack resistance, etc. <P>SOLUTION: In the belt for papermaking machine in which an outer peripheral surface is laminated to the felt side of a base body, the belt for papermaking machine comprises an intermediate layer having an outer peripheral surface in contact with the base body and the outermost layer positioned on the outer periphery of the intermediate layer. The intermediate layer is a polyurethane cured with dimethyl-thiotoluenediamine, the outermost layer is a cured polyurethane cured with a curing agent except dimethyl-thiotoluenediamine or a thermosetting resin selected from an epoxy resin and an unsaturated polyester resin. A drainage channel is cut on the outer peripheral surface and the bottom of the drainage channel is cut to a position deeper than the interface between the intermediate layer and the outermost layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a papermaking machine belt (hereinafter sometimes simply referred to as “belt”). More specifically, it is a papermaking machine belt having a multilayer outer peripheral surface and excellent physical properties such as crack resistance, wear resistance, and permanent set.

In a paper mill, a belt for a papermaking machine made of a substrate and polyurethane is used in each manufacturing process. That is, a shoe press belt or a transfer belt is used in the press part of the papermaking process, and a soft calender belt is used in the calendar part.

  These belts are basically composed of a base made of woven fabric or the like for developing the strength of the entire belt, and polyurethane laminated on both sides or one side of the base. In order to manufacture such a belt, a process of applying and impregnating a liquid urethane prepolymer to a substrate and curing it with a curing agent is taken.

In polyurethane for papermaking machine belts, various types of polyurethane are used properly depending on the part used and the application, such as the press part in the papermaking process. Because of the strong pressure between the press shoe and the press shoe, high physical properties are required. In recent years, the operating environment has become increasingly severe in recent years with the increase in the operating speed of papermaking machines due to the improvement in paper productivity and the increase in pressure in the press section. A belt used in such a high-performance papermaking machine is required to have a higher level of performance. In general, a papermaking machine belt is required to have physical properties such as wear resistance, permanent set, crack resistance, and compression fatigue resistance.

  As described above, the belt is formed by laminating polyurethane on both sides or one side of the base. In the case of both sides, the outer peripheral surface is in contact with the felt side, and the inner peripheral surface is in contact with the press roll or the press shoe. Of these, the outer peripheral surface laminated on the felt side is subjected to severe pressure, and a drainage groove is usually provided on the outer peripheral surface to increase dewatering efficiency, so cracks are generated from the bottom and the edge of the drainage groove. It's easy to do. Further, there is a problem that the convex surface located between adjacent drain grooves is easily worn. Therefore, among the polyurethanes constituting the belt, particularly for the polyurethane used as the outer peripheral surface, there is a great demand for improvement in crack resistance and wear resistance.

    In the process for producing polyurethane, a diisocyanate having two isocyanate groups at the terminal and a polyol having a plurality of hydroxyl groups at the terminal are subjected to a polyaddition reaction to first produce a urethane prepolymer having an isocyanate group at the terminal. The liquid urethane prepolymer thus obtained has a low molecular weight, and is cured by adding a curing agent (chain extender) thereto and heating to obtain a solid high molecular weight polyurethane.

The selection of the curing agent for the production of high molecular weight polyurethane is important as it greatly affects the properties of the polyurethane. Typical examples of curing agents for papermaking polyurethanes are dimethylthiotoluenediamine (DMTDA) and methylenebisorthochloroaniline (MBOCA), both of which are frequently used. Among them, MBOCA is excellent in wear resistance, and DMTDA is particularly excellent in crack resistance. Crack resistance is an important property for papermaking belts, and DMTDA is increasingly used in applications that place importance on crack resistance.

  For example, Patent Document 1 provides a papermaking machine belt that can balance crack resistance, abrasion resistance, and permanent distortion resistance when DMTDA is used as a polyurethane curing agent for a papermaking machine belt.

However, in addition to normal cracks caused by strong external forces as cracks generated in the belt, there are small hair-like cracks on the convex surface located between adjacent drainage grooves, so-called hair cracks. Although it was excellent in preventing occurrence, there was a drawback that hair cracks were likely to occur. When the hair cracks are uniformly generated on the surface of the belt convex portion, there is a problem that the frictional wear increases as a result of increasing the surface roughness. Furthermore, the papermaking belt is usually provided with drainage grooves on the outer peripheral surface in order to discharge the squeezed water, but there is a phenomenon that the edge of the convex surface located between adjacent drainage grooves is lost. The phenomenon also tends to occur more easily with DMTDA cured products.

  On the other hand, MBOCA cured product is excellent in wear resistance, but has a defect that cracks are likely to occur. Moreover, in order to improve the abrasion resistance especially as a belt for papermaking machines, usually a polyurethane having a high hardness is selected. However, it has been known that cracks are more likely to occur even in a DMTDA cured product or a MBOCA cured product. That is, generally, improvement in wear resistance and prevention of cracks are contradictory properties, and it has been considered difficult to solve both at once.

JP 2004-52204 A

  As a result of studying this point, the inventors of the present invention have found that the occurrence of cracks often occurs from the bottom and the edge of the drainage groove provided in the polyurethane resin layer on the outer peripheral surface of the polyurethane, and the hair on the belt convex surface. Since attention should be paid to cracking and wear resistance, the resin laminated on the outer periphery (felt side) of the substrate is made up of two or more layers, and the layer that is in direct contact with the substrate (hereinafter referred to as an intermediate layer) is resistant. Laminating materials with excellent cracking properties, and laminating materials with good wear resistance and hair cracking resistance on the outer periphery to form the outermost layer on the outer peripheral surface (hereinafter simply referred to as the outermost layer), and draining on the outer peripheral surface When the groove is provided, by cutting the drainage groove so that the bottom part is deeper than the boundary surface between the intermediate layer and the outermost layer, the bottom part of the drainage groove and the edge thereof become a crack-resistant material, and the outermost layer is resistant to cracking. Abrasion and hair crack resistance Since formed from a material, it found that thereby crack resistance, wear resistance, none of the anti-hair crack resistance is excellent belt obtained.

  Specifically, DMTDA-cured polyurethane is laminated on the intermediate layer, and a thermosetting resin selected from a curing agent other than DMTDA, such as polyurethane cured with MBOCA, epoxy resin, or unsaturated polyester resin, is used as the outermost layer. Laminate.

That is, the present invention relates to a papermaking machine belt having an outer peripheral surface laminated on the felt side of a substrate, the outer peripheral surface including an intermediate layer in contact with the substrate, and an outermost layer positioned on the outer periphery, the intermediate layer being dimethylthiotoluenediamine The outermost layer is a cured polyurethane cured by a curing agent other than dimethylthiotoluenediamine, or a thermosetting resin selected from an epoxy resin and an unsaturated polyester resin, and on the outer peripheral surface. A drainage groove is cut, and the bottom of the drainage groove is cut to a position deeper than the boundary surface between the intermediate layer and the outermost layer.

The belt for the papermaking machine of the present invention has an abrasion resistance by arranging a thermosetting resin selected from a curing agent other than MDMTDA, for example, polyurethane cured by MBOCA, an epoxy resin, or an unsaturated polyester resin in the outermost layer. And excellent hair crack resistance. In addition, the drainage groove is cut deeper than the boundary between the two layers, and the intermediate layer DMTDA-cured polyurethane is exposed at the bottom of the drainage groove and its edge, so cracks from the bottom and its edge occur. On the other hand, since the convex surface located between adjacent drain grooves is the material of the outermost layer, it is possible to prevent the edge portion from being damaged. In this way, a papermaking machine belt that is better than the conventional ones in terms of crack resistance, abrasion resistance, and hair crack resistance is provided.

The structure of the papermaking machine belt of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view of a belt 1, in which a shoe-side resin layer 3 is laminated on the inner peripheral surface of a base 2 and a felt-side resin layer 4 is laminated on an outer peripheral surface.
The felt-side resin layer 4 on the outer peripheral surface includes an intermediate layer 5 and an outermost layer 6. The intermediate layer 5 is in contact with the base and the outermost layer 6 is laminated on the outer side. The belt is provided with a plurality of drain grooves 7 in the running direction. Since the drainage groove 7 is cut so as to be deeper than the boundary surface 9 between the intermediate layer 5 and the outermost layer 6, the exposed intermediate layer 5 forms the bottom surface 8 of the drainage groove 7 and its edge. Yes.

  The belt outer peripheral surface obtained by such a laminating method and the installation of drainage grooves is composed of an intermediate layer 5 and an outermost layer 6, and the outermost layer 6 in contact with the felt side in a papermaking machine is cured with a curing agent other than DMTDA. Polyurethane, such as MBOCA cured polyurethane, or a thermosetting resin selected from epoxy resin and unsaturated polyester resin, so that even if the paper machine is operated at high speed and high pressure, wear, hair cracks, and edges of convex surface Occurrence of partial defects is suppressed. On the other hand, since the drainage groove 7 is cut to a position deeper than the boundary surface 9 between the intermediate layer 5 and the outermost layer 6, the bottom 8 and its edge are DMTDA-cured polyurethane having excellent crack resistance, so that cracks are generated. Hard to do.

  Of the felt-side resin layer 4 that is the outer periphery of the belt of the present invention, the intermediate layer 5 is provided with DMTDA-cured polyurethane, and the outermost layer 6 is particularly required to have wear resistance and hair crack resistance. As the material of the outermost layer 6, a thermosetting resin selected from polyurethane cured with a curing agent other than DMTDA, or an epoxy resin or an unsaturated polyester resin is used.

  In the papermaking machine belt, in addition to the felt side resin layer 4 constituting the outer peripheral surface of the base 2, the shoe side resin layer 3 is usually laminated on the shoe side of the base 2. As the shoe side resin layer 3, thermosetting polyurethane is most often used as in the outer peripheral surface.

In addition, a woven fabric is usually used as the substrate, but in addition, those obtained by laying the two together without being woven, films or knitted fabrics, and those obtained by winding a strip of narrow width in a spiral are used.

  The polyurethane in the intermediate layer reacts with polyol and diisocyanate to form a urethane prepolymer, and then mixed with a curing agent (chain extender), then applied to the substrate, and then dried and cured (heated) To obtain a high molecular weight polyurethane.

Examples of the polyol that is a raw material for generating the urethane prepolymer include polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol, polyester polyols such as polycaprolactone ester, polycarbonate, polyethylene adipate, polybutylene adipate, and polyhexene adipate. Is used.

  As the diisocyanate of the urethane prepolymer raw material, any of known polyurethane raw materials such as tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), m-xylene diisocyanate, and naphthalene diisocyanate can be used. preferable. MDI has various isomers, and the 4,4 ′ isomer is most preferable. A mixture of TDI and MDI can also be used.

In a reaction for producing a urethane prepolymer from a polyol and a diisocyanate, the mixing ratio of the two is an isocyanate group / OH group equivalent ratio of 1.3 / 1 to 4/1, preferably 1.4 / 1 to 1.6 / 1. It is preferable to do so.

The reaction product contains a large amount of unreacted diisocyanate and solvent and is removed by distillation. A prepolymer is obtained as a distillation residue.

Dimethylthiotoluenediamine, which is a curing agent, has various isomers depending on the substitution position of dimethylthio group and amino group, but can be used in the form of a mixture of these isomers as ETHACURE300 (trade name) manufactured by Albemarle, USA. It is available.

Methylenebisorthochloroaniline, which is a curing agent, is available as Iharacamine MT (trade name) manufactured by Ihara Chemical.

The urethane prepolymer and the curing agent are desirably mixed at a mixing ratio such that the equivalent ratio of the active hydrogen group of the curing agent to the isocyanate group of the urethane prepolymer is O.9 to 1.10.

The curing reaction with the curing agent can be performed by a known method. The temperature of the curing reaction is usually 20 to 150 ° C., preferably 90 to 140 ° C., and it is preferable to carry out the reaction for at least 30 minutes.

The urethane prepolymer generally has a low viscosity, and a high molecular weight polyurethane can be obtained by chain-extending it with a curing agent (chain extender). In manufacturing the belt, first, a belt base 2 such as a woven fabric is impregnated with a mixture of a urethane prepolymer and a curing agent for forming the intermediate layer 5, dried and cured (may be heated), and then the intermediate layer 5. Then, a thermosetting resin selected from a mixture of a urethane prepolymer and a curing agent, or an epoxy resin and an unsaturated polyester resin is applied to the outermost layer 6 on the intermediate layer 5 as well. As shown in FIG. 4, a belt is obtained by impregnating and laminating a polyurethane layer on the inner peripheral surface of the substrate 2 and an outer peripheral surface composed of the intermediate layer 5 and the outermost layer 6 on the opposite side.

  When thermosetting polyurethane is used for the outermost layer 6, the types of the raw material polyol and diisocyanate, their mixing ratio, reaction temperature, etc. are substantially the same as those in the intermediate layer 5, but the curing agent is dimethylthiotoluene. A curing agent other than diamine (DMTDA) is used. Such curing agents include aromatic diamines (methylene bisorthochloroaniline (MBOCA), trimethylene bis-4-aminobenzoate, 1,2-bis- (2 aminophenylthio) ethane, methylene dianiline sodium chloride complex, Trimethylene glycol-di-paraaminobenzoate), aliphatic polyols (1,4-butanediol, trimethylpropane), aromatic polyols (hydroquinonequinone diethylol ether), etc., especially wear resistance, hair crack resistance MBOCA is preferable from the viewpoint of properties.

The outermost layer 6 may be made of a thermosetting resin other than polyurethane, such as an epoxy resin or an unsaturated polyester resin. The epoxy resin is preferably a bisphenol A type epoxy resin obtained by condensation of bisphenol A and epichlorohydrin and cured by a curing agent such as an aliphatic amine, aromatic amine, or acid anhydride, and an unsaturated polyester resin. As the unsaturated polyester resin, a mixture of an unsaturated polyester obtained from an unsaturated dicarboxylic acid and a glycol and a polymerizable vinyl monomer such as styrene is cured with a radical initiator such as an organic peroxide. Among the above-mentioned thermosetting resins, epoxy resins are suitable particularly when used for the outermost layer 6 as in the present invention.

An unsaturated polyester resin that is a thermosetting resin is available as Adeka Resin EP4100 (trade name) manufactured by Asahi Denka Co., Ltd.

Another thermosetting resin, bisphenol A type epoxy resin, is available as Iupica 4516P (trade name) manufactured by Iupika Japan.

  A method of laminating polyurethane resin on both surfaces of the base 2 is performed by the following steps as shown in FIGS.

(Process 1)
As shown in FIG. 2, the base 2 is passed between rolls 20 and 21, and the roll is rotated, while the urethane prepolymer to be the shoe-side resin layer 3 is formed on the base 2 and dimethylthiotoluenediamine (DMTDA) as a curing agent. And the shoe-side resin layer 3 is dried and cured (may be heated).

(Process 2)
After drying and curing the shoe side resin layer 3, the front and back of the substrate 2 are reversed, and as shown in FIG. 3, a urethane prepolymer that becomes the intermediate layer 5 on the other surface of the substrate 2 on which the shoe side resin layer 3 is laminated A mixture with DMTDA as a curing agent is applied, dried and cured (may be heated), and the intermediate layer 5 is formed. Further, a mixture of urethane prepolymer which becomes the outermost layer 6 (not shown) and MBOCA which is a curing agent is applied from the upper part of the intermediate layer 5 shown in FIG. 3 and dried and cured (heated). Thus, the felt side resin layer 4 composed of the intermediate layer 5 and the outermost layer 6 is sequentially formed.

When a thermosetting resin selected from an epoxy resin and an unsaturated polyester resin is used for the outermost layer 6, an uncured product such as a condensate of bisphenol A and epichlorohydrin, a mixture of an unsaturated polyester and a polymerizable vinyl monomer, etc. An outermost layer can be formed by adding a curing agent or a radical initiator to a commercially available liquid resin and heating and curing in the same manner as the curing of the urethane prepolymer.

Thus, after the felt-side resin layer 4 is formed on the outer peripheral surface of the substrate 2, the drainage groove 7 is formed. The drainage groove 7 is formed by cutting in the belt running direction using a rotary blade or the like. In the present invention, it is necessary to expose the DMTDA cured polyurethane as the intermediate layer 5 to form the bottom of the drainage groove 7 and the edge thereof, so that the depth of the drainage groove 7 is as shown in FIG. Cutting is performed so as to be deeper than the boundary surface 9 between the intermediate layer 5 and the outermost layer 6.

  In terms of the relative thickness of each layer on the outer peripheral surface, the intermediate layer 5 is preferably 40 to 90, particularly 50 to 80, and the outermost layer 6 is preferably 60 with respect to the total thickness 100 of the felt side resin layer 4. -10, especially 50-20. If the thickness of the intermediate layer 5 is too large (if the thickness of the outermost layer 6 is too small), when the outermost layer 6 is worn during use of the belt, the time when the intermediate layer 5 is exposed to the belt surface comes earlier. Conversely, if the thickness of the intermediate layer 5 is too small (if the thickness of the outermost layer 6 is too large), the boundary surface 9 between the intermediate layer 5 and the outermost layer 6 approaches the bottom 8 of the drainage groove 7, so Cracks may occur in the vicinity of the edge or adjacent groove walls, which is not preferable.

In the present invention, the depth of the drainage groove 7 is 40 to 70, preferably 50 to 60 with respect to the relative ratio 100 as the thickness of the felt side resin layer 4, and the boundary surface 9 is one of the wall surfaces of the drainage groove 7. The drain groove 7 is cut so as to form a part. The depth from the boundary surface to the bottom portion 8 is preferably 10 to 90, particularly 40 to 60 with respect to the depth 100 of the drainage groove 7. If the depth of the drainage groove 7 is deeper than this, a crack may be generated from the bottom portion 8, the vicinity of the edge portion, or the adjacent groove wall portion, which is not preferable. On the other hand, if the depth is smaller than this, the dewatering efficiency of the belt is lowered, which is not preferable.

Hereinafter, the present invention will be specifically described with reference to examples. In each example and comparative example, the urethane prepolymer, the curing agent, and the thermosetting resin used as materials for the intermediate layer and the outermost layer are as follows.
(1) Urethane prepolymer:
Uses “Takenate L2395 (Takeda Pharmaceutical Co., Ltd.)”
(2) Curing agent DMTDA: “ETHACURE300” manufactured by Albemarle (mixture of 80 parts / 20 parts with 3,5-dimethylthio-2,4-toluenediamine / 3,5-dimethylthio-2,6-torundiamine)
(3) Hardener MBOCA: “Iharacamine MT” (methylenebisorthochloroaniline) manufactured by Ihara Chemical
(4) Thermosetting resin:
"Adeka Resin EP4100" (Asahi Denka Co., Ltd.): Bisphenol A type epoxy resin obtained by condensation of bisphenol A and epichlorohydrin

[Example 1]
(Lamination of inner surface polyurethane)
DMTDA was prepared as a curing agent, and the urethane prepolymer was mixed so that the H / NCO equivalent ratio was 0.97.
(Prepolymer coating)
As shown in FIG. 2, the base 2 is stretched between the rolls 20 and 21, and the urethane pre-resist which becomes the inner peripheral surface (shoe side) resin 3 is first applied from the resin coating nozzle 22 onto the base 2 while rotating the roll. A mixture of a polymer and a curing agent is applied, and the shoe side resin 3 is dried and cured.

(Lamination of middle layer polyurethane)
Next, the front and back of the substrate 2 are reversed, and as shown in FIG. 3, a mixture of the urethane prepolymer and the curing agent DMTDA to be the intermediate layer 5 is applied to the other surface of the substrate 2 and dried and cured.

(Lamination of outermost layer polyurethane)
When curing of the intermediate layer 5 proceeds and the fluidity is lost, the urethane prepolymer and the MBOCA curing agent are mixed so that the H / NCO equivalent ratio is 0.97, and the mixture is added from above the intermediate layer 5. After applying and forming the outermost layer 6, it is dried and cured. Thereafter, the reaction was performed at 100 ° C. for 3 hours by the heat source 23 provided above, and the inner peripheral surface polyurethane, the intermediate layer polyurethane, and the outermost layer polyurethane were completely cured.

  Thus, a belt was obtained in which one layer was laminated on the inner peripheral surface of the substrate 2, and two layers of the intermediate layer 5 and the outermost layer 6 were laminated on the outer peripheral surface. The thickness of each layer on the outer peripheral surface is 1.5 mm (75) for the intermediate layer 5 and 0.5 mm (25) for the outermost layer 6 with respect to the total thickness 2.0 mm (100 as a relative ratio) of the felt side resin layer 4. It is.

After the polyurethane is cured, a width of 1.0 mm is used on the outer peripheral polyurethane surface using a rotary blade.
A drainage groove 7 having a depth of 1.0 mm is formed. Thereby, the layer of DMTDA cured polyurethane as the intermediate layer 5 is exposed, and the bottom of the drainage groove is formed.

[Evaluation of physical properties]
The physical properties of the obtained belt sample were measured. The measuring method of physical properties is as follows.
(1) Cracks Measured using the apparatus shown in FIG. Both ends of the test piece 31 are clamped by clamp hands 32 and 32, and the clamp hands 32 and 32 are configured to be able to reciprocate in the left-right direction in conjunction with each other. The tension applied to the test piece 31 is 3 kg / cm, and the reciprocating speed is 40 cm / sec.
In addition, the test piece 31 is sandwiched between the rotary roll 33 and the press shoe 34 so that the outer peripheral surface is in contact with the rotary roll 33, and the press shoe is moved in the direction of the rotary roll to increase the load at 36 kg / cm ₂ . Pressed.
With this device, the reciprocating motion of the test piece was repeated, and the number of reciprocations until a crack occurred at the bottom and the edge of the test piece 31 was measured. Then, the hair crack generation condition was observed about the convex part surface located between the drainage grooves of a test piece outer peripheral surface.

(2) Abrasion resistance It measured using the apparatus shown in FIG. In FIG. 5, the test piece 31 is attached to the lower portion of the press board 35, and the lower surface (surface to be measured) is pressed by the outer peripheral surface coming into contact with the rotary roll 36. A friction piece 57 is provided on the outer periphery of the rotating roll 36, and the contact friction with the rotating roll under pressure is performed for 20 minutes at a pressure of 10 kg / cm and the rotating speed of the rotating roll of 100 m / min. The thickness reduction amount of 31 was measured.

[Example 2]
In Example 1, a belt sample was prepared in the same manner as in Example 1 except that MBOCA cured polyurethane was replaced with Adeka Resin EP4100 (bisphenol A type epoxy resin), which is a thermosetting resin, as the outermost layer resin. The physical properties of were measured. The results are also shown in Table 1.

[Comparative Example 1]
A belt sample was produced in the same manner as in Example 1 except that the outer peripheral surface was a single layer of only DMTDA cured polyurethane used as an intermediate layer in Example 1, and the physical properties of the obtained belt sample were measured. The results are also shown in Table 1.

[Comparative Example 2]
A belt sample was produced in the same manner as in Example 1 except that the outer peripheral surface was a single layer of only MBOCA cured polyurethane used as the outermost layer in Example 1, and the physical properties of the obtained belt sample were measured. The results are also shown in Table 1.

As is clear from the results in Table 1, the belt of the present invention in which the outer peripheral surface is made of two layers consisting of an intermediate layer of DMTDA cured polyurethane and an outermost layer of MBOCA cured polyurethane has crack resistance, abrasion resistance, and hair crack resistance. Sexually improved.
In comparison, the belt of Comparative Example 1 in which the outer peripheral surface is a DMTDA cured polyurethane single layer has good crack resistance, but is insufficient in wear resistance and hair crack resistance, while the outer peripheral surface is The belt of Comparative Example 2, which is a single MBOCA-cured polyurethane layer, has good wear resistance and hair crack resistance, but is inferior in crack resistance.

  According to the present invention, a belt for a papermaking machine having excellent crack resistance, wear resistance, hair crack resistance, and the like is provided, and durability is increased, compared with a conventionally used belt composed of a single layer of outer peripheral polyurethane. Improvements in product quality and cost reduction are expected by improving the productivity of the papermaking process.

It is a cross-sectional view which shows the structure of the belt for papermaking machines of this invention. The belt manufacturing process of the papermaking machine of this invention is shown. The belt manufacturing process of the papermaking machine of this invention is shown. Crack resistance test equipment. Wear resistance test equipment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Belt 2 Base | substrate 3 Shoe side resin layer 4 Felt side resin layer 5 Intermediate layer 6 Outermost layer 7 Drainage groove 8 Drainage groove bottom 9 Boundary surface of intermediate layer and outermost layer
20, 21 rolls
22 Resin coating nozzle
23 Heat source
31 specimen
32 Clamp hand
33 Rotating roll
34 Press shoe
35 Press board
36 rotating roll
37 Friction

Claims (3)

In a papermaking machine belt having an outer peripheral surface laminated on the felt side of the substrate, the outer peripheral surface includes an intermediate layer in contact with the substrate and an outermost layer positioned on the outer periphery, and the intermediate layer is cured with dimethylthiotoluenediamine The outermost layer is a cured polyurethane cured with a curing agent other than dimethylthiotoluenediamine, or a thermosetting resin selected from an epoxy resin and an unsaturated polyester resin, and a drain groove is cut on the outer peripheral surface. A belt for a papermaking machine, wherein a bottom portion of the drainage groove is cut to a position deeper than a boundary surface between the intermediate layer and the outermost layer. The papermaking machine belt according to claim 1, wherein the outermost layer is polyurethane cured with methylenebisorthochloroaniline.   The papermaking machine belt according to claim 1, wherein the thermosetting resin is a bisphenol A type epoxy resin.

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