JPS59176329A - Transparent molding with surface on which both hydrophilic and hydrophobic zones are formed and its use - Google Patents

Abstract

PURPOSE:A molding having a marked effect of condensing water drops near the surface and an excellent effect of preventing formation of mist-form water drops and suited as an agricultural covering material or the like, obtained by forming a pattern of repeated hydrophilic an hydrophobic zones on the surface. CONSTITUTION:The purpose transparent molding is prepared by forming a pattern of repeated hydrophilic and hydrophobic zones on the surface by, for example, a method comprising mixing a synthetic resin (e.g., polyvinyl chloride or polyester resin) with a surfactant, and molding the mixture to produce a film- or sheet-form molding having a surface which is hydrophilic entirely, and forming a pattern of a hydrophobic substance by coating or printing. It is preferred that the proportion of the hydrophilic zone accounts for 51-99% and that of the hydrophobic zone for 49-1%. Further, it is preferred that the contact angle with a water drop in the hydrophilic zone is 60 deg. or below, and that in the hydrophobic zone is 61 deg. or above.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention (rl) relates to a transparent molded article and a method of using this molded article. The present invention relates to a transparent molded product that is effective in preventing this and how to use this molded product.

Conventionally, glass with excellent heat retention, insulation properties, and (d) weather resistance,
Thin plates such as synthetic resin sheets or films have been widely used as covering materials for solar heat-based fresh water production equipment, and as covering materials for greenhouses or tunnels for cultivating useful plants. In this field of application, coating materials with high light transmittance are preferred, and the antifogging properties of the coating material are important.

Below, problems with conventional techniques will be listed, focusing on coating materials for useful plant cultivation, such as tunnels.

A typical example of the covering phase of a greenhouse for cultivating useful plants, such as a tunnel or a tunnel, is a synthetic resin sheet or film. In these synthetic resin sheet tu films, the inner surface of the coating material (
For the purpose of preventing the formation of water droplets on the side facing the inside of a tunnel or tunnel, a method of compounding an antifogging agent into a synthetic resin base material and forming it into a sheet or film (for example, 3/-Agguj
(see publication).

(2) A method in which the synthetic resin base material is formed into a sheet or film without adding an antifogging agent, and then an antifogging agent is applied to the surface of these molded products (for example, Tokkosho!r3-3/ 3C#
Publication No.).

etc. have been proposed, and many other methods have been proposed in addition to these.
Efforts are still being made to improve it.

When using a covering material improved by methods (1) and (2) above, (1) Moisture that evaporates from the soil and cultivated plants inside a greenhouse or tunnel will condense on the inner surface of the covering material and Since it flows down along the surface, it does not condense and adhere to the inner surface of the coating material as water droplets, and the light transmittance of the coating material does not decrease.

(11) Moisture evaporated from the soil and cultivated plants flows down along the inner surface of the covering material, so water droplets do not fall onto the cultivated plants, inhibiting pollination of the cultivated plants and promoting the spread of diseases. Never.

It is possible to achieve the following effects. However, it has been difficult to prevent fog from forming near the inner surface of the covering material when there is a large temperature difference between the inside and outside of the covering material.

Recently, methods for preventing fog generation near the inner surface of coating materials have been proposed, such as Japanese Patent Application Laid-Open No. 2011-2-3, Japanese Patent Application Laid-Open No. 3,2333, and Japanese Patent Application Laid-Open No. 4-1011. j3
Publication No. 57-3g2, Japanese Patent Application Laid-Open No. 1977-3G
/, 2070 Publication, JP-A-57-/, 23.237-A, JP-A-Sho Orfugu 611. Publication No. g, Japanese Unexamined Patent Publication No. 7
-/ A method described in Publication No. 92'14# etc. has been proposed.

These newly proposed methods include (a) using a specific antifogging agent in combination, (b) using a combination of an antifogging agent and a silicone compound, and (・→ an antifogging agent and a fluorosurfactant) The effects of (i) to 1ii) can be achieved by using a combination of the antifogging agent and the bisamide compound, and the like.

However, as agricultural covering materials, the above (1) to (iii)
) is not sufficient. That is,
In addition to the above-mentioned performances (1) to (iii), the covering material surface is non-sticky and has good workability, the surface is difficult to contaminate (excellent stain resistance), and transparency. , has excellent weather resistance and dust resistance, does not bleed out or bleed during long-term use or storage, is easy to bond with a high-frequency sewing machine, and does not become cloudy during use. It is said that it must be equipped with the following.

It has been found that the newly proposed method described in (a) to (a) above is still insufficient in the following points.

■ In both cases, additives are blended into the base resin, so in order to achieve the effects (il to (iii)) above and at the same time avoid undesirable phenomena, the type and amount of additives are adjusted. A huge amount of work is required to select the type of additive, confirm the limit on the amount added, etc.

■ Confirm the presence or absence of interaction between the additives already blended in the base resin and the newly blended additives, and ensure that both are innovated.
Confirming changes in the surface condition of molded products that have been present requires a huge amount of work and long-term confirmation.

■ When actually used as cover for tunnels, etc., the temperature range is from below freezing point to 70°C.
'Q, but it must be stable and maintain a favorable surface state at all times over such a wide temperature range.

As described above, a coating material that has all of the performances (1) to (iii) above and does not have the drawbacks (1) to (3) above has not been proposed in the past.

Under such circumstances, the present inventors have discovered the above (1) to (i).
As a result of extensive research aimed at providing a covering material that has all of the performance characteristics of iii and also does not have the drawbacks of We have discovered that this can be achieved, and have arrived at the present invention.

The gist of the present invention, therefore, resides in a transparent molded article characterized by having hydrophilic regions and hydrophobic regions formed in a repeating pattern on its surface.

The present invention will be explained in detail below.

In the present invention, a molded product refers to a transparent molded product made of glass or synthetic resin.

Glass refers to commonly known silicate glass, noda lime glass, and the like. Synthetic resins refer to those with excellent transparency, such as olefins such as ethylene, propylene, butene, and pentene, vinyl chloride, vinyl acetate, vinyl alcohol, acrylic acid and its derivatives, methacrylic acid and its derivatives, styrene, etc. Monopolymers or copolymers of monomers such as vinyl compounds such as derivatives thereof, diene compounds such as butadiene and cyclopentadiene; polyesters; polyamides; polymers and copolymers such as polybonates or polyimides. It refers to a combination or a combination of these polymers.

Molded products include plates, sheets, films, as well as pipes and tubes.

To produce plates from glass, continuous pulling method,
A roll forming method or the like may be adopted, and a machine conventionally used for pipe manufacturing such as a Danner machine (DANN BRMACH NE) may be used to manufacture the pipe.

For producing plates, sheets, films, etc. from synthetic resins, melt extrusion, solution casting, calendering, laminating, etc. may be used; for producing pipes, tubes, etc., melt extrusion may be used. It is better to use a plate,
A method of post-processing a sheet, film, etc. into a pipe or tube may also be used.

Various resin additives, such as plasticizers, heat stabilizers, and surfactants, can be added to the synthetic resin before it is made into a molded product.

In the present invention, hydrophilic regions and hydrophobic regions are formed in a repeating pattern on the surface of a transparent molded article made of the above-mentioned base material.

The hydrophilic area formed on the surface of the transparent molded object condenses and adheres to the hydrophobic area formed next to it, forming a thin film of water droplets, minimizing the amount of water droplets adhering to the surface of the molded object. In addition, it functions to maintain a high light transmittance.

To form a hydrophilic region and a hydrophobic region on the surface of a transparent molded product, if the molded product is hydrophilic, a hydrophobic substance is immobilized, and in the opposite case, a hydrophilic substance is immobilized. It is better.

In order to fix a hydrophilic substance or a hydrophobic substance on the surface of a transparent molded article, methods such as coating, printing, plasma treatment, sputtering, etc. can be selected depending on the nature of the surface of the molded article.

For example, if the transparent molded product is a plate, sheet, film, etc. made of synthetic resin, the molded product is made by blending a surfactant with the synthetic resin material, the entire surface of the molded product is made into a hydrophilic region, and then the hydrophobic It is good to form a sexual area. In this case, a specific method for forming the hydrophobic region is to apply or print a hydrophobic substance.

In addition, molded products such as plates, sheets, and films can be made without adding surfactants to synthetic resin Ag 3'll.
A method may also be used in which the entire surface of the molded article is made into a hydrophobic region by directly utilizing the hydrophobicity of the base material, and a hydrophilic region is formed on the surface. In this case, effective methods for forming the hydrophilic region include coating, printing, corona treatment, chromic acid oxidation, plasma treatment, and sputtering.

Even if synthetic resin plates, sheets, films, etc. are smooth, there may be small uneven patterns (embossed patterns) on the surface.
It's so good.

The ratio of the hydrophilic region and the hydrophobic region to the entire surface of the molded product is 57 to 99% for the former, and 57 to 99% for the latter. The smaller the proportion of the hydrophobic region on the entire surface of the molded object, the fewer water droplets will adhere to the surface of the molded object.
Although the light transmittance of the molded product improves, the water condensation effect on the surface of the molded product decreases. Therefore, when such a molded product is used as a covering material, there is a disadvantage that fog is generated near the surface, so 1. It doesn't look like f-4. Experiments conducted by the present inventors have revealed that the above-mentioned negative aspects can be solved by setting the amount within the above-mentioned range.

The hydrophilic and hydrophobic regions formed on the surface of the transparent molded article have a repeating pattern. As for the pattern, it is best to arrange circular, oval, triangular, square, lattice, tortoiseshell, and other regular patterns as repeating patterns. in this case,
It is preferable that the hydrophobic regions are separated from each other (the seven regions are not connected to other regions) and dispersed and arranged within the hydrophilic region.

The distribution and arrangement of the hydrophilic regions and hydrophobic regions formed on the surface of the molded article can be arbitrarily set depending on the usage form of the molded article.

For example, in the case of a thin sheet whose molded product is used as an agricultural covering, the inner surface of the part used to cover the ceiling area has more hydrophilic areas to increase light transmittance, and the inner surface of the part used to cover the ceiling area is increased to increase light transmittance; It is preferable to increase the hydrophobic region on the inner surface of the part to promote moisture condensation.

According to experiments conducted by the present inventors, the contact angle of water droplets in the hydrophilic region formed on the surface of the molded article (temperature 23 C1 relative humidity 6
In an atmosphere of zero temperature, the measurement surface of the molded product is covered with one! ／ ／ 0
This refers to the angle formed between the surface of a molded product and a water drop, as measured using a reading telescope manufactured by Elsima Optical ■ with a 00 ml water drop placed on it. The same applies below. ) is 60 degrees or less, particularly preferably SS degrees or less, and it has been found that the water droplet in the hydrophobic region preferably has a contact angle of 67 degrees or more, particularly preferably 65 degrees or more. That is, when the water droplet contact angle in the hydrophilic region is 10 degrees or less, the water droplets attached to the surface of the molded product tend to form a thin film, and the water droplet contact angle in the hydrophobic region is 6 degrees or less.
It has been found that when the temperature is 7 degrees or higher, water droplets adhering to the surface of the molded product tend to maintain their shape. When the water droplet contact angles of the hydrophilic region and the hydrophobic region are each within the above ranges, the water droplets form a thin film in the former and become water droplets in the latter, resulting in the condensation of water droplets on the surface of the molded product as a whole. Good for preventing mist-like water droplets from forming near the surface (can be used as a molded product).

The transparent molded product according to the present invention can be used as a covering material for a seawater freshening device using solar heat (a collector collects fresh water condensed on its inner surface), or as a covering material for an agricultural greenhouse or tunnel. suitable for use.

The present invention has been described above, and has particularly remarkable effects as described below, and its industrial utility value is extremely significant.

(■) When using the transparent molded product according to the present invention as a coating material for a seawater freshening device that uses solar heat,
Sea) By increasing the amount of light reaching the water, the heating effect is enhanced, and the amount of water vapor is increased, while at the same time promoting condensation, flow-down, etc., fresh water can be obtained efficiently.

(2) When the transparent molded product according to the present invention is used as a covering material for agricultural greenhouses or tunnels, it is useful for reducing the humidity in the space inside the facility, preventing the spread of diseases in cultivated plants, and the covering material It is also possible to prevent fog from forming near the inner surface.

Hereinafter, the present invention will be explained in detail based on Reference Examples, Examples, and Comparative Examples, and the present invention is not limited to the following examples unless it exceeds the gist thereof.

Reference example (manufacturing of film) Polyvinyl chloride (〒=7300) / 00 parts by weight Dioctyl phthalate 3 Trixylenyl phosphate j Barium-zinc composite stabilizer 3 Bisamide 01. j 〃Ultraviolet absorber
0. / 77 Hindered amine light stabilizer 0. , /tt Rubitan fatty acid ester mixture, 2// g O'Q
The mixture was supplied to a calender roll heated to 100 mL and rolled in a conventional manner to form a film having a thickness of 0.7 mm. The water droplet contact angle of this film was 35 degrees.

Example: In order to form a hydrophobic region on one side of the film prepared in the above reference example, the surface treatment agent Asahi Guard h manufactured by Asahi Glass ■ was used.
otso was printed in a polka dot pattern of diameter/7□. Full table of polka dot film.

The ratio to the area was set to 7. The water droplet contact angle of this hydrophobic region was 73 degrees.

When this film was used as an agricultural covering material, the amount of condensed water, fog generation evaluation test, antifogging evaluation test, and quality change over time were conducted as follows, and the results are shown in Table 1.

<Amount of condensed water> A field in Nagoya City, Aichi Prefecture, with a width of 2m and a height of 2m and depth!
A single-roofed house with a diameter of
Otobe // Monthly 10th Rain gutters were installed on the lower side of the roof and the water volume was measured. The measurement was carried out for 20 days, and 13 units were calculated as the average value of the amount of water flowing down in 7 hours per square meter of the inner surface of the film, which was m'/n? hr-
There is C.

<Fog generation evaluation test> A test film was placed on the sloped ceiling of a fog observation frame surrounded by wooden boards on all sides with the side printed with the hydrophobic area facing inside, and placed on a pre-prepared aquarium with a water temperature of approximately 1°C. ．．
Leave at room temperature of 2jC for 2≠ hours. Next, while maintaining the water temperature in the aquarium at ≠OC, the room temperature was lowered to 30°C, and after 30 minutes and 7 hours, the fog formation near the inner surface of the film (the surface facing the aquarium) was observed with the naked eye. I observed it.

Furthermore, the room temperature was returned to 2jC and the water temperature was poC.

After leaving it at room temperature, 25C for a week, check the aquarium temperature.
The room temperature was lowered to 0C, and after 7 hours, the formation of fog was observed with the naked eye.

The evaluation criteria were as follows.

-: No fog is observed near the inner surface of the film.

±: Very slight fog is observed near the inner surface of the film.

12. Fog is observed near the inner surface of the film.

Ox: A large amount of fog is observed near the inner surface of the film.

<Anti-fogging property evaluation test> The test film was spread on the same single-roof type house where the amount of condensed water was measured, with the side printed with the hydrophobic area facing inside. The anti-fogging property of the sexual area was observed with the naked eye.

The evaluation criteria were as follows.

"/": Water adheres in a thin film and no water droplets are observed.

+-2": Water is attached in a thin film, but there are only a few large water droplets attached.

"3": Water is attached in a thin film, but large water droplets are partially observed.

"≠": Water does not form a thin film, and small water droplets are observed to be attached in some areas.

"j": Condition in which water does not form a thin film and fine water droplets are observed throughout the film.

Change in quality over time> The prepared test film was stored in a warehouse, and the surface condition of the film was observed with the naked eye after 7 years had passed. In addition, adhesion was performed using a high-frequency sewing machine, and a peel test was performed on the bonded portion to evaluate adhesiveness.

The same surface treatment agent as that printed on the film of Example 1 was printed on one side of the film prepared in Example-Reference Example in a polka dot pattern so that the printed surface occupied λ with respect to the total surface area.

Regarding this film, similar to the film in Example/
Various evaluation tests were conducted. The results are shown in Table 1.

Example 3 A polka dot pattern was printed on one side of the film prepared in Reference Example using the hydrophobic processing agent Medium Eight. The percentage of the total surface area of the polka dot film is 1. ! j%. The water droplet contact angle of this hydrophobic region was 3 degrees.

Regarding this film, similar to the film in Example/
Various evaluation tests were conducted. The results are shown in Table 1.

Comparative example/The resin composition shown in the reference example was further blended with 0.3 parts by weight of an organic siloxane surfactant (manufactured by Nippon Unicar ■; L-7002), and the thickness was adjusted to O0/7n' in the same manner as in the same example. r
A film of L was created.

Various evaluation tests were conducted on this film in the same manner as the film in Example. The results are shown in Table 7.

Comparative example! In addition to the resin composition shown in the reference example, a fluorine-containing compound (
Made by Asahi Glass ■; contains 0.3 parts by weight of Surf 0n 5-it, ts>, and has a thickness of 0/111 m as in the same example.
created a film.

Various evaluation tests were conducted on this film in the same manner as the film in Example. The results are shown in Table 1.

Comparative Example 3 In the resin composition shown in Reference Example, the amount of bisamide was increased to 0,000 g parts by weight, and a film having a thickness of 0,000 m was prepared in the same manner as in the same example.

Various evaluation tests were conducted on this film in the same manner as the film in Example. The results are shown in Table 1.

Comparative Example: Various evaluation tests were conducted on the film prepared in the Reference Example in the same manner as in the Examples. The results are shown in Table 1.

Comparative Example The resin composition shown in the Reference Example had the same composition as that of the same example except that the sorbitan fatty acid ester mixture was not added, and the thickness was 0.5 mm as in the same example. /'mfn film was created.

Various evaluation tests were conducted on this film in the same manner as the film in Example. The results are shown in Table 1.

From Table 1, the following becomes clear.

(1) When the transparent molded article according to the present invention is used as an agricultural covering material, a large amount of water condenses on the inner surface of the covering material, which helps to reduce the humidity inside the facility.

(2) When the transparent molded article according to the present invention is used as an agricultural covering material, there is little fog generated near the inner surface of the covering material, and it exhibits excellent antifogging properties.

(3) The transparent molded product according to the present invention does not deteriorate in quality even when stored for a long period of time.

Applicant: Mitsubishi Motors/Santo Kasei Co., Ltd. 223-

Claims (6)

[Claims] (1) A transparent molded article characterized by having hydrophilic regions and hydrophobic regions formed in a repeated pattern on its surface. (2) The ratio of the hydrophilic region to the surface area of the molded product ranges from 57 to 99, and the ratio of the hydrophobic region ranges from 4t9 to
A transparent molded article according to claim (1), characterized in that: (3) Claims (1) to (1) characterized in that the water drop contact angle in the hydrophilic region is 60 degrees or less, and the water drop contact angle in the hydrophobic region is 47 degrees or more.
Transparent molded product described in Section 1. (4) A method of using a transparent molded product in which a hydrophilic region and a hydrophobic region are formed in a repeating pattern on one surface as an agricultural covering material or a covering material for a solar fresh water production device. (5) The coating material has a hydrophilic region and a hydrophobic region formed in a repeating pattern on the surface, and the water droplet contact angle in the hydrophilic region is to degrees or less, and the water droplet contact angle in the hydrophobic region is 47 degrees. A method of using a transparent molded article according to claim (4), which is characterized in that the above is the above. (6) Claims (4) to (5) characterized in that the transparent molded product is a thin plate made of synthetic resin.
A method using a transparent molded article as described in Section 1.