WO2021234762A1

WO2021234762A1 - Handrail and method for manufacturing same

Info

Publication number: WO2021234762A1
Application number: PCT/JP2020/019583
Authority: WO
Inventors: 伸治九鬼
Original assignee: 三菱電機株式会社
Priority date: 2020-05-18
Filing date: 2020-05-18
Publication date: 2021-11-25
Also published as: JPWO2021234762A1; JP6800391B1

Abstract

The handrail according to the present invention comprises a base body layer that includes at least one reinforced fabric, and a cosmetic rubber layer that covers the surface of the base body layer. At least portions of the base body layer other than the reinforced fabric include chloroprene rubber and a hydrotalcite compound. The chloroprene rubber is a cross-linked rubber in which a metal oxide is used, or is a cross-linked rubber in which an organic peroxide is used.

Description

Handrail and its manufacturing method

This disclosure relates to handrails and their manufacturing methods.

Generally, escalators, auto lines, etc. installed in buildings such as department stores, stations, and airports are equipped with handrails called handrails in order to stably transport passengers.

Due to the diversification of buildings in recent years, such handrails are increasingly used in outdoor environments exposed to rain and wind without roofs. In this case, since it is easily affected by rainwater, humidity, etc., chlorosulfonated polyethylene with excellent weather resistance is used for the decorative rubber layer of the handrail, and polyester cloth with low water absorption is used for the reinforcing cloth. In many cases, the handrail is made of a material different from that used in the indoor environment.

For example, in Patent Document 1 (Japanese Unexamined Patent Publication No. 10-152279), instead of the conventional canvas (cotton fabric) provided inside the handrail, polyester fiber having excellent water resistance (low water absorption) and antibacterial property is obtained. Alternatively, a handrail using a woven fabric made of polyamide fiber as a reinforcing cloth is disclosed, and it is stated that slime due to adhesion and propagation of dust and bacteria to the substrate layer including the reinforcing cloth is suppressed and can withstand outdoor use. Has been done.

Patent Document 2 (Japanese Unexamined Patent Publication No. 08-259759) describes a decorative rubber used for a handrail of an outdoor escalator, which contains an epoxy resin, hydrotalcite, etc. in chlorosulfonated polyethylene used for a decorative rubber layer. It has been disclosed, and it is described that the cosmetic rubber has little decrease in gloss even when used for a long period of time in a complex environment such as water immersion, ultraviolet irradiation, and high temperature and high humidity exposure.

Japanese Unexamined Patent Publication No. 10-152279 Japanese Unexamined Patent Publication No. 08-259759

However, as in Patent Document 1, by using a woven fabric made of polyester fiber or polyamide fiber having low water absorption instead of canvas (cotton fabric) as the reinforcing cloth, water absorption or moisture absorption is less likely to occur, but the substrate layer It is not possible to prevent water absorption or moisture absorption into the inside (parts other than the reinforcing cloth such as the adhesive layer). Therefore, with the long-term use of the handrail, water absorption or moisture absorption into the inside of the handrail gradually progresses. As a result, the rubber (adhesive layer) that adheres the reinforcing cloth and the reinforcing cloth, or the rubber (adhesive layer) that adheres the reinforcing cloth and the anti-tension body made of metal or the like, deteriorates and becomes the reinforcing cloth. Adhesive strength may decrease and peeling may occur between the reinforcing cloth or between the reinforcing cloth and the anti-tension body.

Further, when water-resistant chlorosulfonated polyethylene is used only for the decorative rubber layer as in Patent Document 2, the durability of the decorative rubber layer itself to water immersion, ultraviolet irradiation, high-temperature and high-humidity exposure, etc. is improved, but the handrail. It is not possible to prevent water absorption or moisture absorption from the side opposite to the decorative rubber layer (base layer side). Therefore, it is not possible to prevent peeling between the reinforcing cloth and the reinforcing cloth or between the reinforcing cloth and the tension body due to water absorption or moisture absorption inside the handrail, and corrosion of the tension body.

In this way, with regard to the handrail used in the outdoor environment, the conventional measures for water absorption or moisture absorption focusing on the material of the decorative rubber layer or the reinforcing cloth alone absorb water or moisture inside the handrail during long-term use. It is not possible to prevent the deterioration and damage of the handrail due to the progress of the above.

The present disclosure has been made in view of the above problems, and an object thereof is to suppress deterioration, breakage, etc. of the handrail due to the progress of water absorption or moisture absorption into the inside of the handrail.

The handrail according to the present disclosure is a handrail including a base layer including at least one reinforcing cloth and a decorative rubber layer covering the surface of the base layer.

At least a portion of the substrate layer other than the reinforcing cloth contains chloroprene rubber and hydrotalcite compounds.

The chloroprene rubber is a crosslinked chloroprene rubber using a metal oxide or a crosslinked chloroprene rubber using an organic peroxide.

The method for manufacturing a handrail according to the present disclosure is a method for manufacturing a handrail including a base layer including at least one reinforcing cloth and a decorative rubber layer covering the surface of the base layer.

Chloroprene rubber and hydrotalcite compounds are used as materials for at least a portion of the substrate layer other than the reinforcing cloth.

In the handrail of the present disclosure, since chloroprene rubber having excellent water resistance (low water absorption) is used as a material for members other than the decorative rubber layer and at least the reinforcing cloth, water absorption into the inside of the handrail or Deterioration, breakage, etc. of the handrail due to the progress of moisture absorption can be suppressed.

It is sectional drawing which shows an example of the handrail which concerns on Embodiment 1. FIG. It is sectional drawing which shows the laminated structure of the example of the handrail which concerns on Embodiment 1. FIG.

Embodiment 1.
<Handrail>
The handrail of the present disclosure is a member used as a handrail for passengers such as an escalator and an auto line.

With reference to FIG. 1, the handrail 100 has a substrate layer 2 provided on the side in contact with the guide rail (not shown) and a decorative rubber layer covering the outer surface of the substrate layer 2 (opposite the guide rail). 1 and.

The handrail 100 is, for example, as shown in FIG. 1, a back portion arranged on a guide rail (passenger conveyor balustrade) and a pair of side surface portions extending downward from both ends of the back portion. And a pair of ear portions protruding from the lower ends of the pair of side surface portions in a direction approaching each other. The cross-sectional shape of the handrail 100 is, for example, a C-shape as shown in FIG. The back of the handrail 100 circulates along the guide rail while being engaged with, for example, the top of a guide rail (not shown) having a T-shaped cross section.

The substrate layer 2 includes at least one reinforcing cloth 2a.
At least a portion of the substrate layer 2 other than the reinforcing cloth 2a contains a chloroprene rubber and a hydrotalcite compound.

Note that, in FIG. 1, the substrate layer 2 further includes a tension body 3 embedded along the length direction of the substrate layer 2. However, the tension body 3 may be embedded in the decorative rubber layer 1.

(Cosmetic rubber layer)
As the material of the decorative rubber layer 1, it is preferable to use rubber having excellent tactile sensation, stain resistance, bending fatigue resistance, repeated elongation resistance, and coloring property.

The rubber is not particularly limited, but for example, synthetic rubber such as chlorosulfonated polyethylene (CSM), chloroprene rubber (CR), styrene butandien rubber (SBR), or natural rubber can be used.

Further, considering that the decorative rubber layer 1 is directly exposed to rain or the like, in order to prevent water absorption into the inside of the handrail 100, it is possible to appropriately select the rubber compounding agent so as to have low water absorption. preferable.

In addition, bacteria, mold, etc. propagate in the decorative rubber layer 1 due to contamination such as hand stains of passengers. Therefore, it is preferable to add an antibacterial agent or the like containing a silver component to the rubber. If necessary, the surface of the decorative rubber layer 1 may be coated with an antibacterial agent.

(Base layer)
With reference to FIG. 2, in the handrail 100 of the present disclosure, the substrate layer 2 is formed by adhering a plurality of reinforcing cloths 2a via the adhesive layer 4.

The constituent material of the reinforcing cloth 2a is not particularly limited, and for example, a cotton fabric (canvas) or a woven fabric of chemical fibers such as polyester fiber and aramid fiber can be used. Chemical fiber woven fabrics are more preferable than cotton woven fabrics in terms of water absorption resistance, abrasion resistance, dimensional stability, microbial decomposition resistance, availability, price fluctuations, and the like.

The tension body 3 is not particularly limited, and a metal such as a steel cord or a steel tape or a chemical fiber such as aramid fiber or strong human silk (rayon) can be used. Also, in the case of a handrail with severe bending or an outdoor handrail, it is difficult to bend or there is a possibility of metal corrosion if it is a metal tension material, so it is made of chemical fiber such as aramid fiber or strong human silk (rayon). It is more desirable to use the one.

In this embodiment, the tension body consists of one layer. However, when the handrail is applied to the escalator, the handrail for the escalator has a curved portion, so that the flexibility to bend is required. The handrail may be provided with two or more layers of tension material as long as its flexibility is not lost.

Further, as the material of the tension body, for example, a metal (stainless steel, iron, etc.), a chemical fiber, or the like can be used. When chemical fibers are used, since the flexibility of the tension body can be ensured, a plurality of tension bodies may be arranged. In FIG. 2, two tension bodies 3 are formed on the substrate layer 2, but the formation location of the tension body 3 is not limited to this.

In the present embodiment, at least the adhesive layer 4, which is a portion other than the reinforcing cloth, contains chloroprene rubber having excellent water resistance (low water absorption) and hydrotalcite compounds. More specifically, the adhesive layer 4 contains chloroprene rubber as a main component and hydrotalcite compounds.

In the present specification, the "main component" of a certain composition means a component whose ratio to the total amount of the composition is more than 50% by mass. The ratio of the main component to the total amount is preferably 70% by mass or more, more preferably 80% by mass or more, and further preferably 90% by mass.

In the present embodiment, as the chloroprene rubber having excellent water resistance, a chloroprene rubber crosslinked using a metal oxide (a metal oxide cross-linking system) or a chloroprene rubber crosslinked using an organic peroxide (organic). Chloroprene rubber (of peroxide cross-linking system) is used.

The metal oxide cross-linked chloroprene rubber is a chloroprene rubber cross-linked using a metal oxide as a cross-linking agent. As the metal oxide, known ones can be used, and examples thereof include zinc oxide.

The metal oxide preferably contains zinc oxide as a main component. The metal oxide preferably does not contain magnesium oxide.

The organic peroxide cross-linking type chloroprene rubber is a chloroprene rubber cross-linked using an organic peroxide as a cross-linking agent. As the organic peroxide, known ones can be used, and examples thereof include dialkyl peroxides, alkyl peroxy esters, peroxy carbonates, peroxyketals, and diacyl peroxides.

The organic peroxide preferably contains at least one selected from the group consisting of dialkyl peroxide, alkyl peroxy ester, peroxy carbonate, peroxy ketal and diacyl peroxide dicumyl peroxide as a main component.

As the hydrotalcite compounds, known compounds can be used, and examples thereof include compounds represented by the following chemical formulas.

[Mg _1-x Al _x (OH) ₂ ] _x + [(CO ₃ ) _{x / 2} · mH ₂ O] ^x- (0 <X ≦ 0.33)
These may be used alone or in combination of two or more.

In general, the chloroprene rubber composition is vulcanized while absorbing the generated acid due to the peculiarity that the acid is generated at the time of crosslinking. As such a vulcanization method, for example, a vulcanization method (metal oxide-based cross-linking) in which magnesium oxide and zinc oxide are used in combination is used. However, in this vulcanization method, magnesium chloride generated by the absorption of acid by magnesium oxide has high water absorption, so that the water absorption of the obtained chloroprene rubber becomes high.

Therefore, in order to reduce the water absorption of the chloroprene rubber composition, a method of using a lead compound such as lead oxide as a vulcanizing agent is also known. However, since lead is highly toxic, it is desirable to avoid the use of lead from the viewpoint of reducing the environmental load in recent years.

In the present disclosure, in the vulcanization of chloroprene rubber, a metal oxide-based cross-linking in which zinc oxide and a hydrotalcite compound are used in combination in a metal oxide-based cross-linking, or an organic peroxide and a hydrotalcite compound are used in combination. By using the organic peroxide-based cross-linking, it is possible to provide a handrail having low water absorption (high water resistance) without using lead.

In the reinforcing cloth 2a, it is preferable that the water-resistant chloroprene rubber is sufficiently impregnated into the reinforcing cloth 2a. For the water-resistant chloroprene rubber adhesive (chloroprene rubber before vulcanization) used for impregnation, a kneaded product of the water-resistant chloroprene rubber composition having the same components as the adhesive layer 4 is put into a solvent and stirred at room temperature with a stirring blade. By doing so, it can be prepared. The solvent is not particularly limited as long as it can uniformly disperse the chloroprene rubber composition, and for example, toluene, ethyl acetate, acetone, or a mixed solvent thereof can be used.

The step of impregnating the reinforcing cloth 2a with the water-resistant chloroprene rubber adhesive is not particularly limited as long as the step is such that the water-resistant chloroprene rubber sufficiently permeates the inside of the reinforcing cloth 2a. Dipping by immersing the reinforcing cloth 2a, which is the base material, in a dipping tank filled with the agent and then squeezing excess chloroprene rubber adhesive between the rolls, or gravure rolls that reverse-rotate from the adhesive supply pan. It can be carried out by gravure coating or the like in which the adhesive is scraped up and the adhesive is applied to each side of the reinforcing cloth 2a.

The type of raw rubber for chloroprene rubber is not particularly limited, and may be, for example, either G-type (sulfur-modified) or W-type (non-sulfur-modified). For example, Tosoh's Skyprene B-30, Skyprene B-31, Skyprene R-10 and Skyprene TSR-48 (all of which are trade names), or Showa Denko's Showprene W and Neoprene WX. -J and Showa Plen WRT (both are trade names) can be used. These may be used alone or in combination of two or more.

As a compounding agent for chloroprene rubber, reinforcing fillers such as carbon black and ultrafine silica, non-reinforcing fillers such as calcium carbonate and clay, processing aids such as fatty acid ester and fatty acid calcium hydrochloric acid, phthalic acid and adipine are used. An acid-based plasticizer, an antiaging agent such as aromatic amines and phenols, and a tackifier such as an alkylphenol resin and a petroleum resin can be appropriately blended as needed.

As a kneading method for kneading the composition containing the water-resistant chloroprene rubber, a well-known kneader such as a Banbury mixer, a tumbler, a pressure kneader, a kneading extruder, or an open roll is used to knead the above optional components. A method of kneading uniformly can be mentioned.

With such a handrail configuration, since water-resistant chloroprene rubber is used as the material of the adhesive layer 4, there is an effect of preventing deterioration of adhesion between each layer and corrosion of the tension body due to water absorption. Further, by impregnating the reinforcing cloth 2a with the water-resistant chloroprene rubber adhesive having the same composition as the adhesive layer 4, the chloroprene rubber is impregnated deep into the reinforcing cloth 2a, so that the reinforcing cloth 2a itself absorbs water or moisture. Since the chloroprene rubber adhesive to be impregnated has exactly the same components as the adhesive layer 4, the adhesive strength between the adhesive layer 4 and the reinforcing cloth 2a can be enhanced. This makes it possible to provide a handrail that is extremely unlikely to be deteriorated by water absorption or moisture absorption even after long-term use.

[Example 1]
(Preparation of rubber composition)
Chloroprene rubber (CR) (manufactured by Showa Denko Co., Ltd., trade name: Shoprene WXJ) 100 parts, stearate 2.5 parts, silica (manufactured by Oriental Silicas Corporation, trade name: Tokseal 233) 30 parts, dibutyl phthalate (DBP) 10 parts, zinc oxide (1 type) 5 parts, hydrotalcite (manufactured by Kyowa Chemical Industry Co., Ltd., trade name: Hydrotalsite DHT-4A) 8 parts, sulfur 1.0 part, vulcanization accelerator (D) (large) Sealed type with 1.5 parts of Uchishin Kagaku Kogyo Co., Ltd., trade name: Noxeller D) and 0.5 parts of vulcanization accelerator (TS) (manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., trade name: Noxeller TS). A rubber composition containing CR and hydrotalcite compounds was prepared by kneading using a kneader.

[Comparative Example 1]
(Preparation of rubber composition)
The rubber composition of Comparative Example 1 was prepared in the same manner as in Example 1 except that 4 parts of magnesium oxide was used instead of 8 parts of hydrotalcite.

That is, CR (manufactured by Showa Denko Co., Ltd., product name: Shoprene WXJ) 100 parts, stearic acid 2.5 parts, silica (manufactured by Oriental Silicas Corporation, product name: Tokseal 233) 30 parts, DBP 10 parts, zinc oxide (1 type). ) 5 parts, magnesium oxide 4 parts, sulfur 1.0 part, vulcanization accelerator (D) (manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., trade name: Noxeller D) 1.5 parts, and vulcanization accelerator (TS) ) (Manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., trade name: Noxeller TS) 0.5 parts were kneaded using a closed kneader to prepare a rubber composition.

<Water resistance evaluation>
The following evaluations were made on the vulcanized rubber sample (thickness: 2 mm) obtained by heating each of the rubber compositions of Example 1 and Comparative Example 1 in a mold at 150 ° C. for 15 minutes and further vulcanizing. Was done.

Using a JIS No. 3 dumbbell, the above sample was immersed in water at 50 ° C. for 100, 300 or 500 hours, and the weight of the sample before and after immersion was measured. The rate of change in the weight of the sample (the ratio of the increase in the weight of the sample after immersion to the weight of the sample before immersion) was calculated as the water absorption rate (%). Table 1 shows the water absorption rates of Example 1 and Comparative Example 1. The n number of each sample is 3, and the values in Table 1 are the average values thereof.

From the results in Table 1, the water absorption rate of the vulcanized rubber (sample) obtained from the rubber composition of Example 1 is the water absorption rate of the vulcanized rubber obtained from the rubber composition containing magnesium oxide of Comparative Example 1. It can be seen that the vulcanized rubber of Example 1 has excellent water resistance (low water absorption).

[Example 2]
(Adhesive preparation)
A rubber composition similar to that in Example 1 was prepared.

To this rubber composition, add toluene so as to have a concentration of 10% by mass or 30% by mass, stir with a stirring blade, and when the rubber is uniformly dispersed, further add 10 parts of kumaron resin (dissolved in MEK). Then, the mixture was stirred overnight to prepare an adhesive (an adhesive containing 10% by mass of toluene and an adhesive containing 30% by mass of toluene).

(Adhesive application)
A polyester cloth was dipped in an adhesive containing 10% by mass of toluene in a stainless steel vat for 10 seconds to soak the adhesive. Then, the polyester cloth was pulled up and dried at 100 ° C. for 2 minutes. Then, an adhesive containing toluene having a concentration of 30% by mass was applied twice on both sides with a bar. Each application was dried at 100 ° C. for 2 minutes.

(Vulcanization adhesion)
The unvulcanized rubber of chlorosulfonated polyethylene was placed on the above-mentioned adhesive-impregnated reinforcing cloth and vulcanized at 150 ° C. for 35 minutes in a mold to prepare a test piece for adhesive strength evaluation.

[Comparative Example 2]
A rubber composition similar to that of Comparative Example 1 was prepared.

A test piece for adhesive strength evaluation was prepared in the same manner as in Example 2 except that this rubber composition was used.

<Adhesive strength evaluation>
As an adhesive strength evaluation, 90 ° peel strength after the immersion test was measured for the test pieces of Example 2 and Comparative Example 2 based on JIS K 6854-1.

The shape of the test piece used for the evaluation is 10 mm in width and 140 mm in length. A dipping test was conducted in which the test piece was immersed in water at 50 ° C. for 500 hours, and the peel strength of the test piece before and after the dipping test was measured. The measurement conditions for the peel strength were a test speed of 50 mm / min and a test temperature of 23 ° C.

Table 2 shows the measurement results of the peel strength and the rate of decrease in the peel strength before and after the immersion test (the ratio of the decrease in the peel strength of the test piece after the immersion test to the peel strength of the test piece before the immersion test). The n number of each test piece is 3, and the values in Table 2 are the average values thereof.

From the results in Table 2, the test piece of Example 2 had a smaller rate of decrease in peel strength before and after the immersion test than that of Comparative Example 2 using an adhesive containing magnesium oxide, and had excellent water resistance. When used for a handrail, it is expected to have the effect of suppressing peeling inside the handrail.

It should be considered that the embodiments and examples disclosed this time are exemplary in all respects and not restrictive. The scope of this disclosure is set forth by the claims rather than the description above and is intended to include all modifications within the meaning and scope of the claims.

1 decorative rubber layer, 2 base layer, 2a reinforcing cloth, 3 anti-tension body, 4 adhesive layer.

Claims

A handrail comprising a substrate layer containing at least one reinforcing cloth and a decorative rubber layer covering the surface of the substrate layer.
At least a portion of the substrate layer other than the reinforcing cloth contains chloroprene rubber and hydrotalcite compounds.
The chloroprene rubber is a cross-linked chloroprene rubber using a metal oxide or a cross-linked chloroprene rubber using an organic peroxide, which is a handrail.
The substrate layer is a plurality of reinforcing cloths, a tensioning body, and at least one adhesive layer interposed between the reinforcing cloth and the reinforcing cloth and between the reinforcing cloth and the tensioning body. And, including
The handrail according to claim 1, wherein the adhesive layer contains chloroprene rubber as a main component and a hydrotalcite compound.
The handrail according to claim 1 or 2, wherein the reinforcing cloth is impregnated with the same chloroprene rubber and hydrotalcite compounds as the adhesive layer.
The handrail according to any one of claims 1 to 3, wherein the hydrotalcite compound is a synthetic hydrotalcite compound represented by the following formula.
[Mg 1-x Al x (OH) 2 ] x + [(CO 3 ) x / 2 · mH 2 O] x- (0 <X ≦ 0.33)
The handrail according to any one of claims 1 to 4, wherein the metal oxide contains zinc oxide as a main component.
The organic peroxide comprises at least one selected from the group consisting of a dialkyl peroxide, an alkyl peroxy ester, a peroxy carbonate, a peroxy ketal, and a diacyl peroxide dicumyl peroxide as a main component. The handrail according to any one of 4 to 4.
A method for manufacturing a handrail including a substrate layer including at least one reinforcing cloth and a decorative rubber layer covering the surface of the substrate layer.
Chloroprene rubber and hydrotalcite compounds are used as materials for at least a portion of the substrate layer other than the reinforcing cloth.
The method for producing a handrail, wherein the chloroprene rubber is a crosslinked chloroprene rubber using a metal oxide or a crosslinked chloroprene rubber using an organic peroxide.
The substrate layer is a plurality of reinforcing cloths, a tensioning body, and at least one adhesive layer interposed between the reinforcing cloth and the reinforcing cloth and between the reinforcing cloth and the tensioning body. And, including
The method for producing a handrail according to claim 7, wherein chloroprene rubber as a main component and a hydrotalcite compound are used as the material of the adhesive layer.
The method for manufacturing a handrail according to claim 7 or 8, wherein the reinforcing cloth is impregnated with the same chloroprene rubber and hydrotalcite compounds as the adhesive layer.