JP2000290877A - Water-repellent net and its manufacturing method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve light transmission and air permeability, and to ensure waterproofness and air permeability even when a distribution of mesh openings is generated. SOLUTION: A water-repellent coating is applied to a network in which a large number of holes having an opening length of 1 μm or more and 1.5 mm or less are formed two-dimensionally in parallel to form a water-repellent network. I have.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-repellent net having a net such as a net or a lace having a waterproof property and a water-repellent property, and a method for producing the net.

[0002]

2. Description of the Related Art Materials that can ensure waterproofness and air permeability include materials known for skiing and mountain climbing equipment, and chemical fibers such as Gore-Tex (registered trademark).
In this type of chemical fiber, pores of about 0.2 μm are formed, and air permeability and waterproofness are ensured by utilizing the difference in permeability due to the difference in size between water and water vapor.

[0003]

This type of chemical fiber is
Although it has the advantage that the fabric thickness can be reduced, it has the disadvantage of poor light transmission due to the small pore size, eyes closed during use, and reduced breathability and waterproof performance. ing.

In these materials, it is important to make the pore size uniform, for example, 0.2 to 1 μm.
When the pore size is distributed to a size of about the m diameter, the incidence of water droplet penetration increases, and the waterproof performance is extremely reduced.

[0005] The applicant of the present invention has disclosed Japanese Patent Application No. 8-23371.
No. 6, etc., a fine particle having a functional group on the surface thereof, a coupling material having a functional group capable of chemically bonding to the functional group on the surface of the fine particle, and having a water-repellent functional group in the molecule;
An application has been filed for a binder resin that binds the fine particles and a water-repellent paint containing a solvent of the binder resin as an active ingredient. According to the water-repellent paint, a contact angle of 150 ° or more with water can be easily achieved. can do.

However, when an attempt is made to apply a water-repellent coating to a net or a net such as a lace using such a water-repellent paint having super water repellency, a metal net having a relatively large mesh is used. If the mesh has a mesh size of 0.5 mm or less, there is a problem that clogging occurs. In addition, a mesh material made of a plastic material such as polycarbonate, acrylic, and ABS resin, which is widely used, has a problem in that the mesh material itself by the solvent is used. Melting is a problem, and even the production is unclear.

The present invention has been made in view of such circumstances, and has good water permeability, has both waterproofness and air permeability, and can be applied to various miscellaneous goods and products. It is an object of the present invention to provide a mesh body.

Another object of the present invention is to provide a method for producing a water-repellent net capable of applying a water-repellent paint to a net made of a general-purpose plastic material or a net having a small mesh. .

[0009]

According to the first aspect of the present invention, 1
A water-repellent coating is applied to a net-like body in which a number of holes having an opening length of not less than μm and not more than 1.5 mm are formed two-dimensionally in parallel to form a water-repellent net-like body.

[0010] According to the invention relating to a method for manufacturing a water-repellent net according to the second aspect, a glass bead or a glass net is formed on a mesh body in which a large number of holes having an opening length of 1 µm or more and 1.5 mm or less are formed two-dimensionally in parallel. The present invention is characterized in that the water-repellent paint is applied by a dipping method using a water-repellent paint using polytetrafluoroethylene as a water-repellent powder.

In the case where glass beads are used as the water-repellent powder, the solid content of the water-repellent paint is preferably 5 to 5%.
It is desirable that the content be 30 wt% and the specific gravity of the solvent be 0.6 to 1.6. Further, as the solvent, for example, heptane is used.

When polytetrafluoroethylene is used as the water-repellent powder, the solid content of the water-repellent paint is set to 5-35 wt% and the specific gravity of the solvent is set to 0.
It is more preferable to set it to 6 to 1.6. As the solvent, for example, a fluorine-based solvent is used.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 2 is a schematic view of a water drop 2 dropped on the substrate 1, and FIG. 3 is a schematic view showing a principle of measuring a contact angle which is a measure of the water repellency of the substrate 1.

The contact angle θ shown in FIG. 3 is used as an evaluation scale of the water repellency. When the contact angle θ is measured, a water drop 2 is dropped on the substrate 1 as shown in FIG. The contact angle θ refers to an angle between a tangent line at one of two points where the water droplet 2 contacts the substrate 1 and the substrate surface, as shown in FIG. When this contact angle exceeds 150 °, the substrate 1
Shows super water repellency. As the contact angle θ increases, the water becomes water droplets from the water film and becomes a true sphere when the contact angle exceeds 150 °.

A super-water-repellent material having a very large contact angle
Or, when applied to or coated on a net such as a lace, if the mesh of the net or the lace is smaller than the size of the water drop, the water drop is repelled by the net or the lace and cannot pass through the mesh. Utilizing this property, the net can be applied to a purpose of preventing water from entering or a purpose of pumping water.

(Embodiment 1) In general, the size of a water drop is reminiscent of a diameter of several millimeters. When water is dropped on a super-water-repellent material and observed with a scanning electron microscope (SEM). The smallest water droplet having a diameter of several tens of μm could be observed. Observation of the growth of water droplets from water vapor on the water-repellent material shows that the formation of water droplets starts at 2-3 μm. As shown in FIG. 3, the height h of the water droplet on the water-repellent material is given by h = r where the contact angle is θ.
Since it is about [1 + sin (θ−π / 2)], a water-repellent net can be formed by using a mesh having an opening length (hole width) with a lower limit of about 1 μm.

Here, the opening length of the net means an average length of an opening (hole) of a net or a net such as a lace in a shortest portion. That is, if the (opening) hole is circular,
The opening length refers to the inner diameter of the hole, and if the opening is square,
The opening length refers to the length of the short side of the rectangular hole as shown in FIG. Hereinafter, the opening length of the mesh body is referred to as a mesh size.

FIG. 1 is an experimental result showing the relationship between the mesh size and the clogging rate. In this case, as the water-repellent paint applied to the net, glass beads obtained by pulverizing glass were used as water-repellent powder, and the solid content was 5 wt%. The clogging rate is
The ratio obtained by dividing the area of the coating film forming part under the microscope observation by the visual field area of the microscope is expressed as a percentage.

According to the experimental results of FIG. 1, the mesh size is 1
If it is smaller than μm, the clogging rate exceeds 50% and the properties as a mesh cannot be secured, so 1 μm was set as the lower limit of the mesh size.

FIG. 4 is an experimental result showing the relationship between the mesh size and the penetration rate (water leakage rate). The permeation rate referred to here means that water is poured into a net having a water storage shape such as a tea strainer as shown in FIG.
The weight of the leaked water was measured after one minute, and the ratio of the weight of the leaked water to the weight of the injected water is shown as a percentage. As the water-repellent paint applied to the net-like body, glass beads obtained by pulverizing glass were used as water-repellent powder, and the solid content was 5 wt%.

According to the experimental results shown in FIG. 4, the upper limit of the mesh size is 1.5 mm because the permeability rapidly rises to 50% or more with the mesh size of 1.5 mm as a boundary.

(Embodiment 2) In the case where a mesh having a mesh size larger than 0.5 mm is used as the mesh, the water-repellent coating is performed without causing clogging even if the method of applying the water-repellent paint is not specified. be able to. Further, when the mesh is made of a metal material, the water-repellent coating can be performed without causing the material to be dissolved, even if the water-repellent coating is not specified.

However, when the mesh size is smaller than 0.5 mm or when a general-purpose plastic material is used as the net, a conventionally known material such as that disclosed in Japanese Patent Application No. 8-233716 may be used as it is, The coating methods such as spray coating, brush coating, and gun coating cannot perform water-repellent coating without causing the above-mentioned problems.

Therefore, in this embodiment, dipping coating (dipping coating) is employed. The dipping coating can apply a water-repellent treatment to details having a complicated shape.

The solvent-type water-repellent paint is mainly composed of water-repellent powder,
It consists of a binder and a solvent for adjusting the concentration of these components. Furthermore, an additive used to enhance the dispersibility of the water-repellent powder or extend the life of the coating film, or an undercoat material that enhances the adhesion to the substrate may be added.

In this embodiment, glass beads or PTFE (polytetrafluoroethylene) beads are used as the water-repellent powder.

However, the specific gravity of the solvent is preferably about 0.6 to 1.6, and the surface tension is preferably about 16 to 22 dyn / cm ² . In fact, glass beads and PTF
When an E-type bead is used and the specific gravity of the solvent is variously changed to examine the boundary of the mesh size where clogging occurs / does not occur, an experimental result as shown in FIG. 6 is obtained. If the specific gravity of the solvent is less than 0.6, the volatility becomes too high,
It volatilizes in a short time and cannot be used as a paint for dipping. Further, the specific gravity of the solvent is 1.6.
As it gets larger, the mesh size boundary that clogs
Upper limit of mesh size defined from the experimental results of FIG.
It becomes larger than 5 mm.

Therefore, glass beads and PTFE
When the system beads are used as a water-repellent powder, the specific gravity of the solvent is 0.1.
It has been found that a range of 6-1.6 should be used.

FIG. 7 shows the solid content ratio (wt.) Of the water-repellent paint.
5 shows the results of an experiment in which the boundary of the mesh size where clogging occurred / non-occurring was examined with various changes in%). When the solid content is less than 5 wt%, glass beads,
Also in the case of PTFE beads, the fixability of the water-repellent powder becomes insufficient, and the water-repellent powder cannot be sufficiently exhibited. On the other hand, if the solid content is too high than 35 wt%, the viscosity increases and clogging occurs instantaneously without waiting for drying. In the case of glass beads, the solid content is 3%.
If the content exceeds 0 wt%, the boundary between the mesh size at which clogging occurs and the mesh size at which clogging does not occur becomes larger than the upper limit condition of the mesh size of 1.5 mm shown in FIG. In the case of PTFE beads, the boundary between clogged / non-clogged mesh size does not exceed the upper limit condition of the mesh size of 1.5 mm until the solid content exceeds 50 wt%.

Therefore, when glass beads are used as the water-repellent powder, the solid content is controlled to fall within the range of 5 to 30% by weight. When PTFE beads are used, the solid content is set to fall within a range of 5 to 35 wt%.

The surface tension of the solvent must be set smaller than the surface tension of water, and is 16 to 22 dyn / cm.
^Be within the range of ² .

As a solvent that satisfies the conditions for the specific gravity, surface tension, and solid content of the water-repellent paint, relatively easily available solvents include, for example, heptane (specific gravity: 0.68, Surface tension 19.6 dyn / c
m ² ), which is a fluorine-based solvent for PTFE-based beads.

When heptane is used as a solvent, the water-repellent powder is used as glass beads, and the solid content is 5% by weight,
The water-repellent coating was able to be performed on the mesh of the plastic material having a mesh size of 1.5 mm by using the dipping method without any problem. Similarly, when a fluorine-based solvent is used, the water-repellent powder is PTFE-based beads, and the solid content of the beads is about 30 wt%, the dipping method is also used.
The water-repellent coating was able to be performed on a mesh of a plastic material having a mesh size of 1.5 mm without any problem.

In the dipping method, bubbles generally cause a problem. In this case, since the surface tension of the solvent is set to be low, the generation of bubbles can be suppressed.

In order to protect the substrate (the net in this case) on which the water-repellent coating film is formed, it is important to apply the water-repellent paint as thinly as possible and to dry it as quickly as possible. The dipping coating in which the water-repellent coating is performed only by dipping in the water-repellent paint is advantageous in this respect as compared with other coating methods. To make the paint thinner,
The solid content ratio may be reduced to such an extent that the water repellency does not decrease. After dipping, to obtain quick drying,
Heating air may be applied to the painted surface.

The water-repellent coating film may be formed on the net by printing using a roller using the above-described water-repellent paint.

(Application Example 1) FIG. 8 shows an application example in which a water reservoir and a flower insert 4 are constituted by the water-repellent mesh formed as described above.

(Application Example 2) FIG. 9 shows an application example in which a vase 5 requiring a flower stop such as a sword mountain is formed by the water-repellent mesh.

(Application Example 3) FIG. 10 shows an application example in which an umbrella 6 is formed by the above-mentioned water-repellent mesh.

(Application Example 4) FIG. 11 shows an application example in which the screen 7 is formed by the above-mentioned water-repellent mesh.

(Application Example 5) FIG. 12 shows an application example in consideration of a case where the momentum of the water is strong. In such a case, as shown in FIG. The second and subsequent water-repellent nets may prevent water from entering.
As an example of using a plurality of water-repellent nets in such a manner, an umbrella shown in FIG. 10, a screen door shown in FIG. 11, and an arcade are suitable. When the water-repellent nets are stacked, it is better to form a space between the water-repellent nets with spacers interposed therebetween, so that more waterproof property can be secured.

(Application Example 6) In FIG. 13, a net not subjected to the water-repellent treatment and a water-repellent mesh body subjected to the water-repellent treatment as described above are overlapped to enhance the waterproofness. FIG. Also in this case, it is better to form a space between the water-repellent nets with a spacer interposed therebetween, whereby more waterproofness can be secured.

(Application Example 7) FIG. 14 shows a configuration in which a water-repellent net supported by four pillars 8 is disposed above a clothesline where laundry is dried, and a rain cover that prevents the clothesline from raining. FIG.

(Application Example 8) Utilizing vibration and momentum of water,
The water-repellent net can also be applied to those having a valve function for switching passage / blocking of the flow of water. In other words, if the mesh size is selected according to the intensity of the generated vibration, water does not flow in a state without vibration, and when vibration occurs, water flows as fine water droplets through the mesh of the network. A valve function can be achieved. Therefore,
The water repellent net of the present invention can be applied to an object utilizing water or the like.

Application Example 9 Since the water-repellent net of the present invention can realize a net having both air permeability and waterproofness, the water-repellent net of the present invention can be used for shoes, clothing, sports goods, etc. May be applied. Only by using the water-repellent net of the present invention in the portion near the outside air contact side including the outermost side, it is possible to prevent the intrusion of water from the outside and release the sweat that has become water vapor to the outside. Therefore, if a moisture absorbing material is used for the inner, comfortable sporting goods can be realized.

It should be noted that the water-repellent net of the present invention allows fishing to float,
The roof of the rainy practice hall and the roof of the rainy game hall may be configured. Furthermore, you may make it apply the water-repellent mesh of this invention to various other miscellaneous goods and products.

[0048]

According to the first aspect of the present invention, a water-repellent coating is applied to a net-like body in which a large number of holes having an opening length of 1 μm or more and 1.5 mm or less are formed two-dimensionally in parallel. Since the mesh is formed, the aperture size is larger than that of the chemical fiber having air permeability and waterproofness, thereby improving light transmission and air permeability, and generating a distribution in the mesh opening size. In this case, waterproofness and air permeability can be ensured.

According to the second aspect of the present invention, glass beads or polytetrafluoroethylene is added to a water-repellent powder in a network in which a number of holes having an opening length of 1 μm or more and 1.5 mm or less are formed two-dimensionally in parallel. A water-repellent net is manufactured by applying a water-repellent coating by a dipping method using a water-repellent paint. That is, a dipping method using a water-repellent paint having super water repellency (dip coating method)
As a result, a thin coating film can be formed evenly on the net-like body.

[Brief description of the drawings]

FIG. 1 is a graph showing a relationship between a mesh size and a clogging rate.

FIG. 2 is a schematic view of a water drop dropped on a substrate.

FIG. 3 is a schematic diagram illustrating a principle of measuring a contact angle of water, which is a measure of the water repellency of a substrate.

FIG. 4 is a graph showing the relationship between mesh size and permeability.

FIG. 5 is a view showing a tea strainer constituted by the water-repellent mesh of the present invention.

FIG. 6 is a graph showing a boundary between a specific gravity of a solvent and a mesh size at which clogging occurs.

FIG. 7 is a graph showing a boundary between a solid content of a water-repellent paint and a mesh size at which clogging occurs.

FIG. 8 is a view showing a flower insertion made of the water-repellent mesh of the present invention.

FIG. 9 is a view showing a vase constituted by the water-repellent mesh of the present invention.

FIG. 10 is a view showing an umbrella constituted by the water-repellent mesh of the present invention.

FIG. 11 is a view showing a screen door constituted by the water-repellent mesh body of the present invention.

FIG. 12 is a diagram showing an example in which the water-repellent mesh of the present invention is used in an overlapping manner.

FIG. 13 is a view showing an example in which the water-repellent net of the present invention is used by being superimposed on a normal net.

FIG. 14 is a diagram showing a rain cover of a clothesline made of the water-repellent net of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Board 2 Water drop 4 Flower insertion 5 Vase 6 Umbrella 7 Screen door 8 Prop

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaya Fujino 3-19-2 Nishi Shinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Corporation (72) Inventor Kenji Ota 3-19 Nishi Shinjuku, Shinjuku-ku, Tokyo No. 2 Inside Nippon Telegraph and Telephone Corporation (72) Kazuyoshi Tateishi Inventor 3-19-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Seiichiro Mizuno 1-3-1 Gotenyama, Musashino City, Tokyo No. NTT Advanced Technology Co., Ltd. (72) Inventor Chiemi Nishi 1-3-3 Gotenyama, Musashino-shi, Tokyo, Japan Inside NTT Advanced Technology Co., Ltd. (72) Inventor Reiko Shimada 1-3-1-3 Gotenyama, Musashino City, Tokyo NTT Advanced Technology Corporation (72) Akiya Yasuhiro Tsukamoto 1-3-1 Gotenyama, Musashino-shi, Tokyo NTT Advanced Technology Co., Ltd. (72) Inventor Nobuhiro Funakoshi 1-3-1, Gotenyama, Musashino-shi, Tokyo・ F-term within T Advance Technology Co., Ltd. (reference) 4D075 AB01 CA36 CA38 DA21 DB31 DC38 EA07 EB02 EB18 EB56 4L031 BA19 BA33 DA00 4L033 AC03 CA17

Claims (6)

[Claims] 1. A water-repellent net formed by applying a water-repellent coating to a net in which a large number of holes having an opening length of 1 μm or more and 1.5 mm or less are formed two-dimensionally in parallel. body. 2. A water-repellent paint in which glass beads or polytetrafluoroethylene is used as a water-repellent powder in a network in which a large number of holes having an opening length of 1 μm or more and 1.5 mm or less are formed two-dimensionally in parallel. A method for producing a water-repellent net, characterized in that a water-repellent coating is applied by a dipping method using a liquid. 3. In the dipping method, when glass beads are used as the water-repellent powder, the water-repellent paint has a solid content of 5 to 30 wt% and a specific gravity of the solvent of 0.6 to 1.6.
3. The method for producing a water-repellent net according to claim 2, wherein: 4. The method according to claim 3, wherein the solvent is heptane. 5. In the dipping method, when polytetrafluoroethylene is used as the water-repellent powder, the water-repellent paint has a solid content of 5-35 wt% and a specific gravity of the solvent of 0.6-1.6. 3. The method for producing a water-repellent net according to claim 2, wherein: 6. The method according to claim 5, wherein the solvent is a fluorinated solvent.