JPH07164569A - High hardness double layer roll - Google Patents

Abstract

PURPOSE:To provide a high hardness double layer roller suitable for a calender roll for paper making. CONSTITUTION:In a resin roll wherein a surface of a roll core metal is coated by upper and lower two thermosetting resin layers, the resin layers are composed of an upper stuck thermosetting resin layer of resin hardness of JISC80-95 and a lower stuck thermosetting resin layer of 30-200% in elongation at break of resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high hardness multi-layer roll, and more particularly to a high hardness multi-layer roll suitable as a calender roll for papermaking.

[0002]

2. Description of the Related Art In the paper manufacturing industry, rolls having a high surface hardness are used in the dewatering process of paper and the finishing process such as polishing and smoothing. In particular, a supercalender for producing high-quality paper such as printing paper, coated paper, and glassine paper requires a roll covered with a material having a small nip width even under high pressure. These materials include natural stone, cotton, paper, wool,
Asbestos, non-woven fabric, etc. have been used, but among them, asbestos cannot be used from a hygienic point of view, and in recent years, these have been replaced by hard resins such as urethane, nylon and epoxy resins. For example, as disclosed in JP-A-61-696, a roll cored bar provided with a thermosetting resin layer containing an inorganic powder having a Shore D hardness of 70 or more;
Shore A on the outside of the roll core metal
40-D75 rubber layer is formed, and Shore D80 is formed on it.
A roll provided with the above thermosetting resin layer is proposed.
The Shore D hardness referred to here is the same value as the JISC hardness.

The rubber layer is used as the lower adhesive layer, because the thermosetting resin of the upper adhesive layer may be destroyed due to internal strain due to shrinkage during the curing reaction. This is to alleviate problems such as cracks in the upper adhesive layer or peeling between the upper and lower layers due to the relaxation.

[0004]

By the way, for example, recent papermaking machines have been gradually operated at high temperature, high pressure and high speed in order to improve paper quality or production efficiency.
Along with this, the roll temperature is often used at a high temperature of about 100 to 120 ° C to 180 ° C. For this reason, there is an increasing risk that the roll surface material will be destroyed due to expansion and contraction due to heat.

When the roll of Japanese Patent Publication No. 63-58086 is used as a roll used under such a high temperature, the rubber of the lower sticking layer softens due to heat under the above-mentioned conditions of use, and the upper sticking layer is The hard resin is likely to be deformed, the pressure applied by the roll is insufficient, the performance cannot be exhibited, and the problem that the upper adhesive layer is broken due to deformation is caused.

The present inventor has conducted research to improve such problems, and has developed a papermaking roll that can be used even at high temperatures and has excellent formability.

[0007]

The features of the high hardness multi-layered roll of the present invention that achieves the above object are a resin roll in which the surface of a roll core is covered with two thermosetting resin layers, the upper and lower layers. The upper thermosetting resin layer has a resin hardness of 80 to 95 in JISC, and the lower thermosetting resin layer has an elongation at break of 30 to 200%. . In the above structure, the core metal is not particularly limited, but a general iron core is used.

The overlaid thermosetting resin layer having a hardness of JIS C80 to 95 is, for example, an epoxy resin, a phenol resin,
It can be made of thermosetting resin such as urethane resin, and it is formed by putting the resin roll of the semi-finished product on which the lower sticking layer is formed in the casting mold for upper sticking and injecting and hardening the prescribed resin. You can The hardness of the upper layer is JIS
If it is less than C80, there is a problem that it is broken due to deformation due to a high nip pressure, and if it exceeds JISC95, it adversely affects the performance and quality of paper, so that the above range is set.

The lower sticking layer, like the upper sticking layer, can be formed of, for example, a thermosetting resin such as an epoxy resin, a phenol resin, a urethane resin, and the core metal is put in a casting mold for the lower sticking. It can be formed by injecting and hardening a predetermined resin. If the elongation of the resin of the lower adhesive layer at break is less than 30%, the thermosetting resin of the upper adhesive layer causes internal strain due to shrinkage during the curing reaction, and at that time, the elongation of the resin itself of the lower adhesive layer is small. There is a problem that this internal strain cannot be relaxed and cracks are likely to occur. On the contrary, when the elongation exceeds 200%, the lower adhesive layer is repeatedly deformed to a large extent due to local pressure during roll operation. Therefore, the heat generation of the lower laminating layer exceeds the heat resistant temperature of the material, which causes a problem that the material is likely to be destroyed, so that the above range is set.

[0010]

According to the present invention, since the elongation of the resin of the lower laminating layer at break is as large as 30 to 200% and it is highly elastic, the strain of the upper laminating layer during molding is relieved and cracks are generated. There is no. Also, since the material is a thermosetting resin, it does not soften even at high temperatures and can fully exhibit the characteristics of the high-hardness resin of the upper adhesive layer, so it can be used as a paper finishing roll, especially as a super calender roll. Most suitable.

[0011]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the examples.

Example 1 The surface of an iron core (170φ × 200 l) was blasted,
After applying the adhesive, it is put in a lower layer casting mold and POREA R-300 (Ihara Chemical Industry Co., Ltd.) is injected.
It was cured at 0 ° C. for 1 hour.

The elongation at break of the thermosetting resin forming this underlayer was 150% as measured by a breaking test using a tensile tester according to JIS K6301. The surface of the lower sticking layer that has been demolded after curing is polished to make the thickness of the resin layer 5 mm, an adhesive is applied, and this is put in a casting mold for sticking the epoxy resin TA-1595. (Sanyo Chemical Co., Ltd.) was injected and cured at 100 ° C. for 1 hour.

The surface hardness of the thermosetting resin forming the upper adhesive layer was measured according to the JISC hardness measurement method, and was 90 in JISC.

The multi-layer resin roll that has been demolded after curing is further heat-treated at 180 ° C. for 5 hours, and after cooling, the upper layer is 10
It was polished to a thickness of mm to obtain a high hardness multilayer roll.

No abnormalities such as cracks and peeling were observed during demolding and polishing.

The multi-layer resin roll manufactured as described above is used as an upper roll, and a lower roll is made up of a pair of iron jacket rolls. The nip pressure is 250 kg / cm and the peripheral speed is 200 m /.
sec, heating roll surface temperature 180 ° C continuously 8
After the time rotation test, the surface was inspected for cracks and peeling by visual inspection and percussion, but no abnormality was found.

COMPARATIVE EXAMPLE 1 Instead of the under layer of the high hardness multi-layer roll of Example 1, the same epoxy resin TA-1595 (Sanyo Kasei Co., Ltd.) as the upper layer was used as the lower layer. Was produced.

This resin roll was subjected to 180
When heat treatment was performed at 5 ° C. for 5 hours and then surface polishing was performed, cracks were generated in the upper adhesive layer during surface polishing. The elongation at break of this resin forming the underlayer was 3% as measured by the same method as in Example 1. It was destroyed because the internal strain of the upper adhesive layer was not relaxed.

Comparative Example 2 Instead of the undercoat layer of the high hardness multi-layer roll of Example 1, a vulcanized nitrile rubber having an elongation at break of 540% was used to form the undercoat layer, and the example was formed thereon. The top adhesive layer of No. 1 was injected, and similarly cured, heat-treated and polished to prepare a resin roll.

During the production, no cracks were generated on the surface of the upper adhesive layer, and no abnormality such as peeling was observed.

Next, the roll of this example was subjected to a rotation test under the same conditions as in Example 1. As a result, the rubber melted and fractured between the upper and lower sticking layers in 0.25 hours. This is because the lower adhesive layer was greatly deformed due to the local pressure during the roll operation, and the material was destroyed by heat generation.

[0023]

EFFECTS OF THE INVENTION According to the high hardness multi-layer roll of the present invention, which comprises a thermosetting resin having a predetermined property as the lower sticking layer and the upper sticking layer, the elongation at break of the lower sticking layer is 30 to 200. %, Which is highly flexible, there is no problem such as cracks during roll forming and use, and peeling does not occur. In addition, as a paper finishing roll for which a resin roll having a particularly high surface hardness and a large nip pressure has been demanded, it is possible to provide a roll having good finishing performance, and there is an effect that manufacturing is easy.

Claims (1)

[Claims] 1. A resin roll in which the surface of a roll cored bar is covered with upper and lower two thermosetting resin layers, wherein the thermosetting resin layer on the top has a resin hardness of 80 to 95 in JISC,
The underlying thermosetting resin layer has an elongation at break of resin of 30 to 200.
%, A high hardness multi-layer roll.