JPH0357846B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a synthetic resin-lined cloth hose for use in fire hoses and the like.

Conventional technology In recent years, in order to carry out fire extinguishing operations quickly and smoothly,
There is an increasing demand for lightweight fire hoses. There is also a demand for lighter weight hoses with similar structures other than fire hoses. On the other hand, in recent years extremely strong and flexible synthetic resins have become available, and by using these synthetic resins as the lining of hoses, it has basically become possible to reduce the weight of these hoses. However, in reality, this has not been realized due to various inconveniences in manufacturing technology.

When manufacturing a hose with a rubber or synthetic resin lining on the inner surface of a woven or knitted cylindrical fabric, such as a conventional fire hose, the tube is molded from rubber or synthetic resin by extrusion molding, and the outer surface of the tube is Alternatively, a method has been widely used in which an adhesive is applied to the inner surface of the cylindrical fabric, the tube is drawn into the cylindrical fabric, and the tube is adhered to the inner surface of the cylindrical fabric to form a lining.

Further, a cylindrical fabric is immersed in a rubber latex liquid to form a coating of the latex rubber on the outer surface of the cylindrical fabric, and then the cylindrical fabric is turned over inside and outside to use the rubber coating as an lining, Methods of obtaining cloth hoses are also known.

In addition, coating layers of rubber or synthetic resin are simultaneously formed on both the inner and outer surfaces of a coarse cylindrical fabric by extrusion molding, and the outer coating layer and the inner coating layer are integrated through the holes of the cylindrical fabric. , methods for improving adhesive peel strength are also known.

Furthermore, there is also a method in which a synthetic resin coating layer is directly formed on the outer surface of a cylindrical fabric by extrusion molding, and this is turned inside out to form a fabric hose.

Problems to be Solved by the Invention However, all of these methods have various problems, and cannot be said to be suitable as a method for manufacturing a lightweight fire hose lined with synthetic resin.

In other words, the method of drawing and pasting a synthetic resin tube into a cylindrical fabric requires a large number of steps and is expensive, and it is difficult to make the amount of adhesive uniform when applying adhesive to the tube or cylindrical fabric. However, it has the disadvantage that the adhesiveness between the tube and the cylindrical fabric is difficult to maintain. Also, when the tube is drawn into the cylindrical fabric, a large force is applied to the tube due to friction with the cylindrical fabric, so if the tube is made thin, it will easily stretch and become distorted, making it difficult to form a lining with a uniform thickness. was difficult.

Furthermore, the method of dipping a cylindrical fabric in latex to form a coating on its outer surface and then turning it over to form a hose is an extremely excellent method for manufacturing a rubber-lined fire hose. However, since latex with excellent physical properties cannot be obtained using synthetic resin, it is not suitable as a method for lining with synthetic resin.

Furthermore, the method of forming and integrating coating layers on both the inner and outer surfaces of a cylindrical fabric is not preferable because the hose becomes thick and heavy.

Furthermore, the method of forming a synthetic resin coating layer on the outer surface of the cylindrical fabric by extrusion molding and turning it inside out to make a hose is the most promising method for producing a lightweight hose lined with synthetic resin. It is believed that. However, this method
It has the disadvantage that the adhesion between the coating layer and the tubular fabric is not sufficient.

Especially for fire hoses, extremely high quality is required for safety, and these performances are strictly regulated by the Ordinance of the Ministry of Home Affairs. Adhesion between the coating layer and the cylindrical fabric is also included in these required performances, and an adhesion peel strength of 4.5 kg or more at a width of 3.8 cm is required. Therefore, a hose with insufficient adhesiveness cannot be used as a fire hose.

Generally, not only fire hoses but also hoses through which fluid flows require adhesive strength between each layer, and those with insufficient adhesive strength cannot withstand use as hoses.

The present invention has been developed in view of the above circumstances, and is capable of stably manufacturing a hose that is highly productive, lightweight, flexible, and has a high adhesion peel strength between a cylindrical fabric and a coating layer. The purpose is to provide a method.

Means for Solving the Problems The method of the present invention is to apply a thermoplastic polyester elastic resin, R value (-NCO component/-OH component molar ratio) to the outer surface of a cylindrical fabric formed by weaving or knitting fibers ) is 0.95 to 1.05, the outer layer is a thermoplastic synthetic resin selected from the group consisting of a fully thermoplastic type thermoplastic polyurethane elastic resin, and a copolymer or blend of a thermoplastic polyvinyl chloride resin and a thermoplastic polyurethane resin. The A hardness is 65.
~ 80 degrees Celsius, R value is 1.05 to 1.3, the inner layer is at least two layers of synthetic resin mainly composed of thermoplastic polyurethane elastic resin of incomplete thermoplastic type, thermoplastic polyurethane forming the interior Under temperature conditions such that the melt viscosity of the elastic resin is in the range of 3,000 to 20,000 ps, at least two or more layers are molded and covered by an extrusion molding method, and the tube is made into the cylindrical shape by reducing the pressure inside the cylindrical fabric. Apply it tightly to the outer surface of the fabric, then turn it inside out.
It is characterized by feeding pressurized steam into the hose.

The thermoplastic polyurethane elastic resin in the present invention includes polytetramethylene glycol and 1,4-
A polyurethane resin whose main components are butanediol and 4,4'-diphenylmethane diisocyanate is desirable.

The thermoplastic synthetic resin of the outer layer is a thermoplastic polyester elastic resin with an R value of 0.95 to 1.05.
A fully thermoplastic type thermoplastic polyurethane elastic resin, a copolymer of a thermoplastic vinyl chloride resin and a thermoplastic polyurethane resin (for example, manufactured by Toagosei Kagaku Kogyo Co., Ltd., trade name Aron NP) or a blend are suitable. be.

The method of the present invention will be explained below with reference to the drawings. FIG. 1 shows the step of forming a synthetic resin coating layer on the outer surface of a cylindrical fabric in the method of the present invention.

1 is a cylindrical product obtained in this step, and the second
As shown in the figure, a synthetic resin coating layer 3 is formed on the outer surface of the cylindrical fabric 2. Therefore, this cylindrical object 1
By turning over the inner and outer surfaces, a hose A is obtained in which the coating layer 3 is located on the inner surface of the cylindrical fabric 2 and the tubular fabric 2 is lined with the coating layer 3, as shown in FIG.

In FIG. 1, 4 is an extrusion device. An extrusion head 5 is installed in the center facing downward, and the extrusion head 5 is equipped with two extruders 6.
a and 6b are attached. The extrusion head 5 consists of an outer shell 7, an intermediate 8, and a core 9, and an outer resin passage 10a is provided between the outer shell 7 and the intermediate 8.
An inner layer resin passage 10b is provided between the intermediate body 8 and the core body 9.
are formed respectively, and the resin passage 10
a and 10b are combined at the tip of the intermediate body 8,
An annular discharge port 11 is formed. Further, a cavity 12 is formed in the center of the core body 9, and a suction member 13 is provided at the rear of the cavity 12. The inner diameter of the tip of the cavity 12 is the same as that of the cylindrical fabric 2.
It is approximately equal to or slightly larger than the outer diameter of the

14 is a mandrel chip. The mandrel tip 14 has a cylindrical shape whose outer diameter is approximately equal to or slightly smaller than the inner diameter of the cylindrical fabric 2, and is provided at the front end of the cavity 12 of the extrusion head 5. It is positioned with a slight distance between it and the inner surface of the body.

Also attached to the rear of the mandrel tip 14 is a rod 15 which extends rearwardly through the cavity 12 of the extrusion head 5. A holder 16 having a generally bullet-shaped cross section is attached to the rear end of the rod 15. Small rollers 17 are rotatably supported on both shoulders of the holder 16, and are supported by support rollers 18. ing.

19 is a feeding device. The feeding device 19
consists of a pair of feed rollers 21a, 21b with annular grooves 20a, 20b formed in the center;
One roller 21a is moved by the cylinder 22.
It is designed so that it can move into and out of contact with the other roller 21b. Therefore, the feeding rollers 21a, 2
The rod 15 is fitted into the grooves 20a and 20b of the rod 1b. The feeding rollers 21a, 2
1b rotate in synchronization with each other and are actively driven.

Reference numeral 23 is a preheating furnace, and hot air is blown into the preheating furnace 23 from a hot air blowing port 24 to heat the inside of the preheating furnace 23.

The suction member 13 has a suction port 25 connected to a vacuum pump to reduce the pressure inside the cavity 12.

A water bath 26 is provided below the extrusion head 5, and a reversing roller 27 is rotatably supported within the water bath 26.

28 is a guide roller, 29 is a take-up device, and each has a pair of rollers 30a, 3.
A pair of endless belts 3 stretched across 0b
1a and 31b.

Function 2 is a cylindrical fabric. The cylindrical fabric 2 is
It is wound around a reel 32 in a flat folded state, and is pulled out from the reel 32 and fed from above the device via a guide roller 33. The cylindrical fabric 2 is placed over the outside of the holder 16, passes between a small roller 17 and a support roller 18, moves downward, and is further held between feeding rollers 21a and 21b of the feeding device 19. By driving the feed rollers 21a and 21b, the cylindrical fabric 2 is fed downward along the rod 15.

The cylindrical fabric 2 first enters the preheating furnace 23, where it is heated by hot air. The tubular fabric 2 is then introduced into the cavity 12 of the extrusion head 5. Furthermore, the cylindrical fabric 2 passes through the cavity 12 of the extrusion head 5, covers the mandrel tip 14 at its lower end, is inflated to have a substantially circular cross section, and forms a gap between the mandrel tip 14 and the front end of the extrusion head 5. Proceed downward through the gap.

On the other hand, thermoplastic synthetic resins 34a and 34b are extruded from the extruders 6a and 6b. One extruder 6a extrudes a synthetic resin 34a having properties required depending on the use of the hose, and the other extruder 6b extrudes a thermoplastic polyurethane elastic resin 34b. Both synthetic resins 34a and 34b pass through the outer layer resin passage 10a and the inner layer resin passage 10b, respectively, of the extrusion head 5, join at the tip of the intermediate body 8, unite, and proceed to the tip of the extrusion head 5. From the discharge port 11, the outer layer 35a of the synthetic resin 34a and the inner layer 35b of the thermoplastic polyurethane elastic resin 34b are discharged.
A two-layer thermoplastic synthetic resin tube 3 consisting of
5 and is extruded.

At this time, since the pressure inside the cavity 12 is reduced, the air inside the thermoplastic synthetic resin tube 35 is also sucked through the grains of the cylindrical fabric 2, and the pressure is reduced. Therefore, the thermoplastic synthetic resin tube 35
Since the inside of the cylindrical fabric 2 is reduced in pressure, its diameter is contracted and the cylindrical fabric 2 is pressed against the surface of the cylindrical fabric 2.

At this point, the thermoplastic synthetic resin tube 35 has just been extruded and is still at a high temperature and has plastic deformability, so it is closely and firmly adhered to the outer surface of the cylindrical fabric 2. A cylindrical article 1 having a coating layer 3 on the outer surface of a cylindrical fabric 2 is molded.

The molded cylindrical object 1 is transferred to the flat molding device 15.
The water passes through the water bath 26, travels downward, is folded flat, and enters the water bath 26, where it is thoroughly cooled as a whole. The traveling direction is then reversed by a reversing roller 27 within the water bath 26 , and taken up by a take-up device 29 and wound onto a take-up reel 36 .

A cylindrical article 1 obtained in this way is formed by forming a synthetic resin coating layer 3 on the outer surface of the cylindrical fabric 2.
By turning over the inner and outer surfaces using a known method, a hose A lined with synthetic resin is obtained as shown in FIG.

Next, pressurized steam is introduced into this hose A,
The film layer 3 is heated to remove distortion and wrinkles, and to improve the adhesion peel strength between the film layer 3 and the tubular fabric 2.

In the extrusion process described above, since the diameter of the synthetic resin tube 35 is slightly larger than that of the cylindrical fabric 2, wrinkles may not be formed in the coating layer 3 in the length direction of the hose A in the state of the hose A. be.
Therefore, in the present invention, 0.5~
Pressurized steam of about 3.0 kg/cm ² is introduced to remove the wrinkles and improve the adhesion and peel strength.

Examples Next, more specific examples of the configuration of the present invention will be shown. The cylindrical fabric 2 uses a cylindrical fabric. The tubular fabric uses two yarns made by twisting eight 20-count polyester fiber spun yarns as the warp, 632 in total, and as the weft,
6 1500 denier long fiber yarns of polyester fiber
This yarn is woven into a cylindrical shape with an inner diameter of 65 mm by inserting 39 threads per 10 cm.

In the present invention, the synthetic resin 3 serving as the outer layer 35a
As 4a, a thermoplastic synthetic resin is used which has the characteristics required depending on the purpose of the hose. For example, in the case of manufacturing fire hoses, thermoplastic polyester elastic resin is suitable.

The thermoplastic polyester elastic resin is a synthetic resin obtained by block copolymerizing aromatic polyester and polyether, and among them, flexible ones are preferable. Commercially available ones are suitable. This thermoplastic polyester elastic resin can be easily extruded, has excellent antiblocking properties, and is extremely easy to process. In addition, it is strong and highly extensible, and has excellent heat resistance, cold resistance, chemical resistance, mold resistance, and hydrolysis resistance, making it extremely suitable as a synthetic resin for lining fire hoses.

In addition, the synthetic resin 34b used for the inner layer 35b
is a thermoplastic polyurethane elastic resin. The thermoplastic polyurethane elastic resin is mainly composed of diisocyanate, polyol, and glycol, and the diisocyanate includes 4,4'-
Diphenylmethane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, tridene diisocyanate, hexamethylene diisocyanate, etc., and polyols include polyethylene adipate, poly1,4-butylene adipate, polycaprolactone, polytetramethylene glycol, etc. Examples of glycols include ethylene glycol, 1,4 butanediol, 1,6 hexanediol, and bishydroxyethoxybenzene. Among these, a combination of 4,4'-diphenylmethane diisocyanate, polytetramethylene glycol, and 1,4-butanediol is particularly desirable because it has excellent mold resistance and hydrolysis resistance.

This thermoplastic polyurethane elastic resin is preferably relatively flexible and has a hardness of Shore A hardness.
It should be around 65-80 degrees. Since the thermoplastic polyurethane elastic resin penetrates into the grains of the tubular fabric as an adhesive, it has a large effect on the feel of the hose. If a hard material is used, the hose will lose its flexibility and become hard, which is not desirable.

Furthermore, as the thermoplastic polyurethane elastic resin, the total -OH of polyol and glycol is
The molar ratio between the component and the -NCO component of the diisocyanate (R value = -NCO component/-OH component) is 1.05 ~
1.3, a thermoplastic polyurethane elastic resin of the incompletely thermoplastic type is used. This incomplete thermoplastic type polyurethane elastic resin has −
It has an NCO group, and under the influence of heat and water, urethane bonds and unreacted isocyanate (-
(NCO group) to form a crosslink, which can improve the adhesion and peeling strength with the cylindrical fabric 2.

Further, the thermoplastic polyurethane elastic resin 34b is
By extruding at a temperature where the melt viscosity is in the range of 3,000 to 20,000 ps, particularly preferably 5,000 to 10,000 ps, the adhesive peel strength with the tubular fabric 2 is improved.
If the melt viscosity is less than 3,000 ps, the thermoplastic polyurethane elastic resin 34b will enter the grains of the cylindrical fabric too much, making the hose hard; if it exceeds 20,000 ps, it will be difficult to enter the grains, resulting in insufficient adhesive strength.

In the present invention, the synthetic resin 34a used for the outer layer 35a of the coating layer 3 is not limited to the above-mentioned thermoplastic polyester elastic resin. As another example, thermoplastic polyurethane can also be used. In this case, unlike the thermoplastic polyurethane elastic resin for the inner layer 35b, the R value is
It is preferable to use a completely thermoplastic type thermoplastic polyurethane elastic resin having a molecular weight of about 0.95 to 1.05. A completely thermoplastic type thermoplastic polyurethane elastic resin has excellent antiblocking properties and moldability, and is therefore suitable as a synthetic resin for the outer layer 35a.

In addition, thermoplastic vinyl chloride resin can also be used, but those containing a large amount of plasticizer such as DOP have poor adhesion with the thermoplastic polyurethane elastic resin of the inner layer 35b, causing delamination between the inner and outer layers. Possible and undesirable. Therefore, when using polyvinyl chloride resin, it is preferable to use non-plastic thermoplastic vinyl chloride resin. Furthermore, it is also good to use a copolymer or blend of a thermoplastic vinyl chloride resin and a thermoplastic polyurethane elastic resin. In this case, since both the inner layer 35b and the outer layer 35a contain thermoplastic polyurethane elastic resin, the above-mentioned delamination will not occur.

Furthermore, it is also possible to form an intermediate resin layer between the inner layer 35b and the outer layer 35a. Examples of the intermediate resin layer include a blend of a thermoplastic polyester elastic resin and a thermoplastic polyurethane elastic resin, and by forming this intermediate resin layer, the adhesive strength can be further improved.

Further, although the synthetic resin used for the inner layer 35b is mainly composed of thermoplastic polyurethane elastic resin in the present invention, it is not necessary that it consists only of thermoplastic polyurethane elastic resin. A small amount of thermoplastic polyester elastic resin may be blended, or a small amount of non-plastic thermoplastic vinyl chloride resin or the like may be blended.

Effect of the invention The hose manufactured according to the present invention has a tubular fabric 2
and the covering layer 3 are uniformly and firmly bonded to each other. In the hose obtained by the method of the above-mentioned specific example, the adhesion peel strength between the cylindrical fabric 2 and the coating layer 3 is 7 to 10 kg/3.8 cm in the longitudinal direction, and 8 to 10 kg/3.8 cm in the circumferential direction. 11Kg/3.8cm,
Satisfactory adhesive peel strength was obtained. Furthermore, the present invention satisfies the above-mentioned performance requirements and allows selection of a low-cost, easily processable resin for the outer layer, and the hose shown in the above-mentioned specific example can be satisfactorily used as a fire hose. It was something I could endure.

[Brief explanation of drawings]

FIG. 1 is a central vertical sectional view of the apparatus, showing the process of forming a coating layer on the outer surface of a tubular fabric by the method of the present invention. FIG. 2 is a cross-sectional view of a cylindrical article formed by the process shown in FIG. 1, and FIG. 3 is a cross-sectional view of a hose formed by turning over the inner and outer surfaces of this cylindrical article. A... Hose, 1... Cylindrical object, 2... Cylindrical fabric, 3... Film layer, 35... Tube, 35a...
...outer layer, 35b...inner layer.

Claims (1)

[Claims] 1 The outer surface of a cylindrical fabric formed by weaving or knitting fibers is coated with thermoplastic polyester elastic resin, R value (-
A group consisting of fully thermoplastic type thermoplastic polyurethane elastic resins with a molar ratio of NCO component/-OH component of 0.95 to 1.05, and copolymers or blends of thermoplastic polyvinyl chloride resins and thermoplastic polyurethane resins. The outer layer is a thermoplastic synthetic resin selected from Covering the tube with at least two layers while molding at least two or more layers by an extrusion molding method under temperature conditions such that the melt viscosity of the thermoplastic polyurethane elastic resin forming the inner layer is in the range of 3000 to 20000 ps, A method for manufacturing a hose, comprising: reducing the pressure inside the tubular fabric to bring the tube into close contact with the outer surface of the tubular fabric, then turning it over and introducing pressurized steam into the hose. 2 The thermoplastic polyurethane elastic resin is a polyurethane resin containing polytetramethylene glycol, 1,4-butanediol and 4,4'-diphenylmethane diisocyanate as main components. A method for manufacturing a hose according to scope 1.