JP6097155B2 - Contamination-resistant vinyl chloride resin molded body and exterior member, and method for producing contamination-resistant vinyl chloride resin molded body - Google Patents

Description

  The present invention relates to a resin molded body having excellent stain resistance against dirt caused by dripping or the like. More specifically, the present invention relates to a resin molded article having a specific shape of irregularities on the surface of a specific thermoplastic resin molded article, which is excellent in stain resistance and in which deterioration in performance of stain resistance over time is suppressed.

  Conventionally, metal exterior members such as tin, which have been used as exterior members for building roofs, are subject to deterioration over time due to their weight and rust, and various resin materials are used as alternative materials. A so-called resin exterior member has been proposed.

  Examples of such a resin exterior member include a polycarbonate resin exterior member excellent in transparency and impact resistance. The polycarbonate resin exterior member is known to have a flat plate shape, a corrugated plate shape, and the like, and is used for carports, terraces, sound insulation plates, and other building material corrugated plates (roof corrugated plates).

  Moreover, as other resin, the vinyl chloride resin excellent in coloring property and workability is mentioned. As an exterior member using a vinyl chloride resin, a laminated body in which a vinyl chloride resin and a metal plate are laminated as well as the above-described flat plate shape and corrugated plate shape are known. These are used for roof surrounding members such as rain gutters, shutter cases, and outer walls.

  And these resin-made exterior members are excellent in weather resistance and have been improved to be usable for a long time such as several years or several decades by years of technical studies. However, another problem that is not caused by material deterioration is a reduction in appearance due to adhesion of various pollutants caused by wind and rain because of being exposed to the outdoor environment for a long time.

  Although such a decrease in appearance does not directly affect the strength or the like of the resin exterior member, it impairs the aesthetic appearance and decreases the value of the entire structure including the resin exterior portion. It has become a challenge. One of the causes of such a decrease in appearance is contamination caused by adhesion or residual water droplets such as raindrops (hereinafter sometimes referred to as “raindrop stains”).

  For this raindrop, various proposals have been made to improve the antifouling property by applying various antifouling coating layers to the resin surface of the resin exterior member (see, for example, Patent Documents 1 to 3).

Japanese Patent No. 4119014 Japanese Patent No. 3470336 Japanese Patent No. 3161595

  However, the resin exterior member provided with the coating layer in this way has a concern that the coating layer may be peeled off from the base material when exposed to sunlight or wind and rain in long-term outdoor laying. In addition, in order to provide such a coating layer, the chemical industry production such as the manufacturing process and cost increase of the resin exterior member, and the optimum design load of the coating layer forming material required every time the composition of the coating layer is changed There is also concern about the generation of large loads at the level.

  Then, this invention makes it a subject to provide the resin molding which can suppress the external appearance fall by raindrops for a long period of time irrespective of a coating layer, for example, can be used suitably for a building exterior member.

  This inventor earnestly examined in order to provide the technique which suppresses the external appearance fall of the resin-made exterior members irrespective of a coating layer. The inventor first paid attention to the surface state of the resin exterior member in which raindrops are generated. Then, intensive studies were made on the relationship between the water droplets that cause raindrops and the surface shape of the resin exterior member, the chemical composition of the resin itself, and the like.

  Specifically, the present inventor has examined the prevention of drooling stains by providing the surface with minute irregularities and utilizing the expression of water repellency due to the surface tension of water droplets. As a result, surprisingly, for example, a resin such as a polyester resin, which is not easily maintained in shape against an external force, is used on the surface, and a vinyl chloride resin that is appropriately deformed against the external force and has excellent resilience is used on the surface. By providing a micro-concave shape with a concave-convex shape, specifically a distance between the convex portions (concave-concave shape pitch) and a rising length of the convex portion (concave / convex depth), an excellent raindrop stain prevention effect on the surface of the resin molded body It was found that can be expressed.

That is, the first present invention comprises a resin composition containing a vinyl chloride resin as a main component, and has a concavo-convex shape satisfying all of the following conditions (a) to (c) on the surface: It is a resin molding.
(A) The uneven pitch (λ) is 500 μm or less (b) The uneven depth (d) is 20 μm or more and 250 μm or less (c) The ratio (λ / d) of the uneven pitch (λ) to the uneven depth (d) is 1 ≦ λ / d ≦ 3

  In the present invention, the “main component” means a component having the largest mass% among the components constituting the resin composition. In the present invention, other resins and various additives other than the vinyl chloride resin may be contained in the resin composition as long as the effects of the present invention are not impaired.

  The molded body according to the first aspect of the present invention is sheet-like, and preferably has the above-described uneven shape on at least one surface.

  The second aspect of the present invention is an exterior member using the vinyl chloride resin molded body according to the first aspect of the present invention.

  More specifically, in the second aspect of the present invention, it is preferable that the base material is laminated on a surface side different from the surface having the concavo-convex shape of the vinyl chloride resin molded body according to the first aspect of the present invention. The “base material” is not particularly limited, such as a metal base material, a ceramic base material, or a resin base material other than vinyl chloride resin, but is preferably a metal base material, particularly a metal plate, more specifically a steel plate. Is preferred.

The third aspect of the present invention is a process of providing an uneven shape satisfying all of the following conditions (a) to (c) on the surface while molding a resin composition containing a vinyl chloride resin as a main component or after molding. It is a manufacturing method of the vinyl chloride resin molded object characterized by providing.
(A) The uneven pitch (λ) is 500 μm or less (b) The uneven depth (d) is 20 μm or more and 250 μm or less (c) The ratio (λ / d) of the uneven pitch (λ) to the uneven depth (d) is 1 ≦ λ / d ≦ 3

  In 3rd this invention, it is preferable to provide the above-mentioned uneven | corrugated shape on the surface by the thermal transfer process using an embossing roll or an embossing plate.

  In 3rd this invention, it is preferable to provide an uneven | corrugated shape in the sheet | seat surface, after shape | molding a resin composition in a sheet form.

  The molded body according to the present invention has one characteristic in that it has a specific uneven shape on the surface. In the molded product having a specific uneven shape on the surface, when a water droplet adheres to the surface, an air pocket is formed between the water droplet and the concave portion. That is, although the convex part on the surface of the molded body is wet, the concave part comes into contact with trapped air, and the surface of the molded body is in a non-uniform wet state. Further, due to the presence of the air pocket, the contact angle of water attached to the surface is increased, and the water repellency of the surface of the molded body is increased. This makes it difficult for the dirt component contained in the water droplets to adhere to the molded body, facilitates the water droplets to flow, and can effectively prevent raindrops.

  In addition, the molded body according to the present invention has another feature that it is made of a resin composition containing a vinyl chloride resin as a main component. In general, a vinyl chloride resin is softer than a polyester resin or the like, and its shape is likely to be restored over time against deformation. For example, excessive friction and stress may occur on the surface of the molded product under the manufacturing process and actual use environment. This friction and stress may cause unevenness on the surface of the molded product. If used, deformation due to friction or stress can be corrected over time and restored to its original uneven shape. In addition, it is easy to formulate with almost no deterioration in physical properties and yellowing in an outdoor ultraviolet environment as compared with polyester resins. Thereby, a desired uneven shape can be maintained over a long period of time, and raindrops can be suppressed for a long period of time.

  Furthermore, the above-described shape restoration performance depends not only on the type of resin used but also on the shape of the formed unevenness. According to the specific uneven shape according to the present invention, the above-described shape restoration performance is suitably exhibited. Easy to be. That is, by using a vinyl chloride resin and forming a molded article having a specific uneven shape on the surface, it is possible to maintain a desired uneven shape for a longer period of time, and to prevent raindrops for a long period of time. .

  As described above, according to the present invention, it is possible to suppress a decrease in the appearance due to raindrops over a long period of time regardless of the coating layer, and to provide a resin molded body that can be suitably used for, for example, a building exterior member. it can.

It is a figure for demonstrating water repellency of the molded object surface by uneven | corrugated shape provision. It is the schematic which shows an example (concave shape) of uneven | corrugated shape. It is the schematic which shows an example of uneven | corrugated shape (column shape). It is the schematic which shows an example (concave type) of uneven | corrugated shape. It is the schematic which shows an example (corrugated) of uneven | corrugated shape. It is a figure for demonstrating the insertion angle of a sheet | seat when embossing is provided to a sheet-like molded object using an embossing roll. 1 is a surface shape roughness chart of a vinyl chloride resin molded body (resin sheet) produced in Example 1. It is a schematic cross section for demonstrating raindrop dirt evaluation (exposure evaluation) of a molded object. It is the model perspective view which illustrated the fall path | route of the raindrop in raindrop dirt evaluation.

1. Vinyl chloride resin molded body The vinyl chloride resin molded body according to the present invention is composed of a resin composition containing a vinyl chloride resin as a main component, and has a concavo-convex shape satisfying all of the following conditions (a) to (c) on the surface. It is characterized by.
(A) The uneven pitch (λ) is 500 μm or less (b) The uneven depth (d) is 20 μm or more and 250 μm or less (c) The ratio (λ / d) of the uneven pitch (λ) to the uneven depth (d) is 1 ≦ λ / d ≦ 3

1.1. Composition of Resin The vinyl chloride resin molded article according to the present invention has one characteristic that it consists of a resin composition containing a vinyl chloride resin as a main component. Regarding the content of the vinyl chloride resin in the resin composition, the lower limit is preferably 40% by mass or more, more preferably 50% by mass or more, and the upper limit is preferably 80% by mass or less, more preferably 70% by mass or less. is there. Vinyl chloride resin is softer than polyester resin and the like, and its shape is likely to be restored over time against deformation. For example, excessive friction and stress may occur on the surface of the molded product under the manufacturing process and actual use environment. This friction and stress may cause unevenness on the surface of the molded product. If used, the deformation due to the friction can be corrected over time and restored to the original uneven shape. In the present invention, by using such a vinyl chloride resin as a main component, a desired uneven shape can be maintained over a long period of time, and raindrops can be suppressed for a long period of time.

  In addition to the vinyl chloride resin, the resin composition may contain other resins and additives as long as the effects of the present invention are not impaired.

  As other resins, thermoplastic resins other than vinyl chloride resins can be used, for example, polyolefins such as polypropylene; polyesters such as polyethylene terephthalate; acrylic resins such as poly (meth) acrylates; urethane resins; Examples thereof include fluororesins such as fluoroethylene. In the resin composition, the lower limit of the content of these other resins is preferably 0% by mass or more, and the upper limit is preferably 20% by mass or less.

  In the present invention, it is preferable to include a plasticizer as an additive in the resin composition. By including a plasticizer, the vinyl chloride resin molded body can be made softer, and the above-described shape restoration effect can be more suitably exhibited. Specific examples of the plasticizer include diisononyl phthalate and bis (2-ethylhexyl) phthalate. The plasticizer content in the resin composition is preferably 20% by mass or more and 40% by mass or less.

  In addition to the plasticizer described above, the vinyl chloride resin may contain, as necessary, known resin additives that are usually blended in synthetic resins for molding, such as lubricants, heat stabilizers, antioxidants, and stabilizers. An agent, an inorganic filler, a coloring agent, etc. can be mix | blended.

  Examples of the lubricant include higher fatty acids or metal salts thereof, zinc stearate, various paraffins, higher alcohols, natural waxes, polyethylene wax, fatty acid esters and fatty acid amides.

  Examples of the heat stabilizer include calcium stearate, barium stearate, dibasic lead stearate, basic lead sulfite, dibasic lead phosphite, dibutyltin dilaurate, dibutyltin malate, dibutyltin mercaptoide, β-diketone compound or , Dioctyltin malate stabilizers, dioctyltin laurate stabilizers, dioctyltin mercaptide stabilizers, and the like.

  Examples of the antioxidant include phenolic, thiodipropionic acid esters, aliphatic sulfides, and disulfide antioxidants. Specifically, 2,6-di-tert-butyl-4-methylphenol 2,2,2′-methylenebis (6-tert-butyl-4-ethylphenol), dilauryl thiodipropionate and the like can be mentioned.

Examples of inorganic fillers include oxides such as calcium, magnesium, and aluminum,
Examples include hydroxides, carbonates, silicates, and the like and composites thereof.

  Examples of the pigment or dye include inorganic pigments such as titanium oxide, zinc white, lead white, gypsum, precipitated silica, carbon black, bengara, molybdenum red, cadmium yellow, yellow lead, titanium yellow, chromium oxide green, ultramarine blue, etc .; permanent -Organic pigments such as Red 4 R, Hansa Yellow 10 G, Benzidine Yellow G R, Permanent Carmine FB, Phthalocyanine Blue B, and Phthalocyanine Green.

  Each of the above various resin additives can be used alone or in combination. The addition amount of the above various resin additives can be selected in a range that does not deteriorate the properties of the molded body, usually in a range of 10 parts by weight or less with respect to 100 parts by weight of the vinyl chloride resin of the substrate. To blend the above plasticizer and other resin additives into vinyl chloride resin, weigh each required amount and use a ribbon blender, a Banbury mixer, a super mixer or other conventionally known blending machines and mixers. That's fine. In this way, a desired resin composition can be obtained.

1.2. Uneven shape on the surface The vinyl chloride resin molded article according to the present invention has high water repellency by having a specific uneven shape on the surface. Hereinafter, the expression of water repellency due to the uneven shape will be described in detail.

  When the water droplets adhere to the surface of the resin molded body, if the surface is a smooth surface, the water droplets adhere to the entire surface of the resin molded body. A layer (air pocket) is created. Regarding such a phenomenon, the Cassie-Baxter model is known as a model representing the relationship between surface roughness and wettability. According to this model, as shown in FIG. 1, when a water droplet adheres to a surface having a concavo-convex shape, a part of the surface of the convex part gets wet, but the concave part comes into contact with trapped air, and the surface of the molded body is In other words, it takes a non-uniform wet condition. In such a case, it is known that the contact angle of water droplets attached to the concavo-convex surface is a contact angle θ ′ as shown in the following formula (1).

In the formula (1), θ ′ is the water contact angle on the uneven surface, θ is the water contact angle on the smooth surface, Q is the ratio of the area where the water droplet is in contact with the surface of the resin molding, and θ _air is the water contact in the air. It is an angle and is 180 ° (ie, cos θ _air = −1). According to the above formula (1), θ ′ approaches 180 ° as the air pocket increases. That is, it turns out that water repellency increases.

In order to generate air pockets when water droplets adhere to the surface of the molded body, the uneven pitch (λ) and the uneven depth (d) of the uneven shape need to be within a predetermined range. That is, the vinyl chloride resin molded body according to the present invention has another feature in that the surface has an uneven shape that satisfies all of the following conditions (a) to (c).
(A) The uneven pitch (λ) is 500 μm or less (b) The uneven depth (d) is 20 μm or more and 250 μm or less (c) The ratio (λ / d) of the uneven pitch (λ) to the uneven depth (d) is 1 ≦ λ / d ≦ 3

  The uneven pitch (λ) may be any pitch that allows air pockets to be formed between the water droplets attached to the surface of the molded body and the surface of the molded body. In this respect, the present invention has an object to prevent raindrops and dirt. In normal rain, water droplets (raindrops) are larger than 500 μm, and the waterdrops that flow as raindrops are larger than that, so that air pockets can be formed. In order to achieve this, the concavo-convex pitch (λ) may be set to 500 μm or less. Preferably it is 400 micrometers or less, More preferably, it is 200 micrometers or less. About a lower limit, it can determine suitably by relationship with (lambda) / d mentioned later.

  Regarding the uneven depth (d), as the depth increases, the water repellency increases, and conversely, the strength decreases. If the strength decreases too much, it becomes difficult to maintain the uneven shape due to physical impact after the manufacturing process or installation. On the other hand, the strength increases as the depth becomes shallower, but the above-described air pocket is difficult to be formed, and the water repellency is deteriorated. Considering these, in the present invention, the uneven depth (d) is set to 20 μm or more and 250 μm or less. The lower limit is preferably 40 μm or more, more preferably 80 μm or more, and the upper limit is preferably 200 μm or less, more preferably 150 μm or less.

  The ratio (λ / d) between the concavo-convex pitch (λ) and the concavo-convex depth (d) is set to 1 ≦ λ / d ≦ 3 in consideration of the above-described strength and water repellency due to air pockets. If λ / d <1, the depth becomes too large, so that the surface shape is crushed depending on the use process and use environment, and the desired water repellency cannot be maintained. On the other hand, if 3 <λ / d, since the pitch becomes too large, it becomes difficult to form air pockets and the desired water repellency cannot be expressed. If 1 ≦ λ / d ≦ 3, the desired water repellency can be expressed by the occurrence of air pockets, raindrops can be appropriately suppressed, and the process can be performed over a long period of time depending on the process and environment of use. The surface shape is not crushed.

  In the present invention, the specific form is not particularly limited as long as it is an uneven shape satisfying the above-described predetermined uneven pitch (λ) and uneven depth (d). For example, a shape having a prismatic convex portion as shown in FIG. 2, a shape having a cylindrical convex portion as shown in FIG. 3, and a lattice-like convex portion (rectangular concave portion) as shown in FIG. Various shapes such as a shape and a shape having a corrugated shape or a curved shape as shown in FIG.

The reason why raindrops are less likely to adhere due to such an uneven shape is specifically as follows.
(1) An air pocket is formed between the water droplet and the resin molded body, and the water repellency of the surface is increased (the water contact angle is increased), so that the water droplet easily flows and dirt is difficult to adhere.
(2) Since an air pocket is formed between the water droplet and the resin molded body, a contact interface between the water droplet and the resin molded body is reduced, and a dirt component in the water droplet is hardly fixed to the surface of the molded body.

  In addition, it is difficult to attach raindrop dirt, and the uneven shape in the present invention has a deeper uneven depth than the conventional uneven shape (deep). Another advantage is that dirt is not noticeable.

  As described above, the vinyl chloride resin molded body according to the present invention is made of a resin composition containing a vinyl chloride resin as a main component, thereby making the most of the performance (softness, shape restoration) unique to the vinyl chloride resin. By having a specific concavo-convex shape, it is possible to exhibit high water repellency and shape maintainability and to suppress dripping dirt over a long period of time.

1.3. Overall Form of Molded Body As long as the vinyl chloride resin molded body according to the present invention has a specific concavo-convex shape on the surface, the overall form is plate-like, columnar, sheet-like (including film-like), etc. It can be set as various forms. In particular, it is preferable to form a sheet-like molded body and have the above-described uneven shape on at least one surface of the sheet. The sheet thickness (sheet thickness including uneven depth (d)) in the form of a sheet is not particularly limited, and can be reduced as long as desired water repellency and strength are obtained. Alternatively, by preparing a base material having a thin vinyl chloride resin layer on the surface, and providing the concave and convex shape together with the base material, a molded body in which the vinyl chloride resin layer is provided along the concave and convex shape of the base material is obtained. Even in this case, it can be said that the thin vinyl chloride resin layer corresponds to a vinyl chloride resin molded article having a specific uneven shape according to the present invention. When it is set as a sheet-like molded product, it is suitable for the following exterior member because it is excellent in handling, for example, it can be cut to an appropriate size and attached to a substrate.

2. Exterior Member The vinyl chloride resin molded body according to the present invention can suppress dripping dirt over a long period of time, and is particularly suitable for exterior members such as rain gutters, roof surrounding members, shutter cases, and outer walls. As for the exterior member, as long as the vinyl chloride resin molded body according to the present invention is used, the specific shape and form are not particularly limited, but it has the uneven shape of the vinyl chloride resin molded body. It is preferable that a base material is laminated (or pasted) on a surface side different from the surface. Examples of the base material include various base materials such as a metal base material, a ceramic base material, and a resin base material other than vinyl chloride resin. In consideration of cost, workability / workability, designability, etc., the metal plate is particularly preferable. More specifically, it is preferable to use a steel plate.

  For example, when a sheet-like molded body is used as the vinyl chloride resin molded body and a plate-like base material (such as a metal plate) is used as the base material, the side opposite to the surface having the uneven shape of the sheet-like molded body The surface (sheet back surface) and one surface of the base material are optionally bonded using an adhesive. By carrying out like this, it can be set as the resin coating board excellent in the designability, and can be used suitably as a building exterior member.

  Conventionally, in an exterior member coated with a resin, there has been a problem that raindrops adhere to the exterior member in a short period of time and the appearance is impaired. Thus, such a problem can be solved.

3. Method for Producing Vinyl Chloride Resin Molded Body The vinyl chloride resin molded body according to the present invention has the following conditions (a) to (b) on the surface while molding a resin composition containing a vinyl chloride resin as a main component or after molding. It can be produced by a method for producing a vinyl chloride resin molded article, comprising a step of providing an uneven shape satisfying all of (c).
(A) The uneven pitch (λ) is 500 μm or less (b) The uneven depth (d) is 20 μm or more and 250 μm or less (c) The ratio (λ / d) of the uneven pitch (λ) to the uneven depth (d) is 1 ≦ λ / d ≦ 3

  In molding the resin composition, injection molding, extrusion molding, or the like can be appropriately selected depending on the shape of the target molded body (use of the molded body). For example, when the resin composition is formed into a sheet shape, the molten resin composition is extruded into a sheet shape through a T-die using a melt extruder, cooled by contacting with a cast roll, and further in a subsequent stage. A sheet-like molded body can be obtained by bringing it into contact with at least one cooling roll and taking it out while cooling. In addition, any known method can be employed for molding the resin composition. For example, a sheet-like molded body can be obtained by an inflation method, a calendar molding method, a solution casting method, or the like.

  What is necessary is just to select suitably as a method of providing uneven | corrugated shape on the surface of a molded object according to the whole shape and magnitude | size of a molded object, such as the thermal transfer process by an embossing roll or an embossing plate, an etching process, and sandblasting process. For example, when the molded body is a sheet-like molded body, thermal transfer processing using an embossing roll or an embossing plate is preferable, and thermal transfer processing using an embossing roll is particularly preferable. However, in the present invention, since the uneven depth (d) of the uneven shape is deeper than before, when the sheet-like molded body is processed using an embossing roll, so-called air smearing is large. Therefore, in order to reduce air smearing, it is preferable to make the molded body insertion angle into the embossing roll shallow. That is, as shown in FIG. 6 (A), when embossing is applied to a sheet-like molded body, if the molded body insertion angle into the embossing roll is deep, the contact time between the embossing roll and the sheet becomes longer. Although air is easily transferred, air stagnation (bubbles) easily occurs between the embossing roll and the sheet. On the other hand, as shown in FIG. 6 (B), when the insertion angle of the molded body into the embossing roll is shallow, bubbles do not easily enter because the contact time between the embossing roll and the sheet is short. In the present invention, the insertion angle α is preferably 30 ° to 80 °, more preferably 45 ° to 70 °.

  In addition, when setting it as a sheet-like molded object, at least one of a cast roll or a touch roll is used as an embossing roll at the time of melt extrusion molding, and while the resin composition is formed into a sheet shape, the specific surface described above is formed on the surface thereof. It is also possible to provide an uneven shape. In this case, the vinyl chloride resin composition and a resin different from the resin composition may be co-extruded and embossed on the surface that becomes the vinyl chloride resin layer.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, unless this invention exceeds the summary, it is not limited to a following example at all.

<Making vinyl chloride resin molding>
Example 1
Laser embossing was performed on a metal press plate at a predetermined pitch and depth to prepare an embossed plate.

  A soft vinyl chloride sheet (sheet made of a resin composition containing vinyl chloride resin as a main component and containing additives such as a plasticizer and a lubricant, thickness 250 μm) heated to 120 ° C. with a hot press machine and the embossed plate are pressed. The emboss shape was given to the surface of the soft vinyl chloride sheet. About the obtained embossed soft vinyl chloride sheet, the surface roughness of the said vinyl chloride sheet was measured with the surface roughness meter, and uneven | corrugated pitch ((lambda)) and uneven | corrugated depth (d) were measured. FIG. 7 shows surface shape measurement data of the embossed soft vinyl chloride sheet according to Example 1.

(Examples 2-5, Comparative Examples 1-5)
In the same manner as in Example 1, an embossed plate having an uneven pitch (λ) and an uneven depth (d) was prepared, and embossed soft vinyl chloride sheets according to Examples 2 to 5 and Comparative Examples 1 to 5 were prepared. did.

<Evaluation of molded vinyl chloride resin>
The following evaluation was performed about the sheet | seat which concerns on Examples 1-5 obtained as mentioned above and Comparative Examples 1-5.

(Water contact angle)
Using a water contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.), the water contact angle of the embossed surface of each sheet of Examples and Comparative Examples was measured.

(Water contact angle after durability test)
A weight of 10 kg per 10 cm square was placed on the embossed surface of each sheet of Examples and Comparative Examples, stored at 40 ° C. for 3 days, the weight was removed, and the water contact angle was measured.

(Rain and dirt exposure assessment)
After installing each sheet of Examples and Comparative Examples in the form shown in FIGS. 8 and 9 on the roof of Mitsubishi Plastics Corporation Nagahama Factory in Mitsuya Town, Nagahama City, Shiga Prefecture, and conducting an exposure test for 3 months, The presence or absence of raindrops was confirmed visually and evaluated according to the following criteria. As shown in FIGS. 8 and 9, each sheet was attached to a steel sheet using an adhesive and used for the test.
○ (Good): The color difference between the color of the sample before the exposure test and the most dirty part after the exposure test is less than 10 × (Poor): The color of the sample before the exposure test and the most dirty part after the exposure test More than 10 color difference with

  The evaluation results are shown in Table 1 below.

As is clear from the results shown in Table 1, Examples 1 to 5 in which the uneven pitch (λ), the uneven depth (d), and the ratio of the pitch to the depth (λ / d) are within the scope of the present invention. It can be seen that raindrop dirt can be appropriately suppressed. Moreover, about Examples 1-5, since the fall of the water contact angle after an endurance test is not recognized, it has a self-restoration performance of uneven | corrugated shape, and it turns out that raindrop dirt can be suppressed over a long term.
On the other hand, as in Comparative Examples 1 and 2, when there is no uneven shape or the uneven shape is too small, raindrops cannot be appropriately suppressed. It is thought that the air pocket cannot be properly formed when raindrops adhere.
In addition, as in Comparative Example 3, when λ / d is too small, the rain pockets can be suppressed by the air pockets, but the water contact angle has changed greatly before and after the durability test, and the self-restoring performance of the uneven shape is demonstrated well. Not. Therefore, it is considered difficult to prevent dripping and soiling over a long period of time.
Further, as in Comparative Examples 4 and 5, when the pitch λ is too large or λ / d is too large, it is not possible to appropriately suppress raindrops. It is thought that the air pocket cannot be properly formed when raindrops adhere.

(Comparative Example 6: When using polyester resin)
Embossed polyester molded body with embossing similar to that in Example 1 applied to the polyester resin layer surface of polyester resin laminated steel sheet (Mitsubishi Resin, product name: EXUM). Got. However, the emboss transferred on the surface of the molded body collapsed, and a line-shaped scratch on the sheet entered, resulting in poor appearance.

  Moreover, when the above-mentioned durability test was performed using the obtained embossed polyester molded body and the water contact angle before and after the durability test was measured, the water contact angle that was 100 ° before the durability test was 80 ° after the durability test. It dropped to. In other words, it was found that when a polyester resin is used, the self-restoring performance of the uneven shape as in the case of using a vinyl chloride resin cannot be obtained.

  Furthermore, the embossed polyester molded body was exposed outdoors in order to evaluate raindrop contamination exposure, but the polyester resin layer turned yellow in one month. In other words, it has been found that when a polyester resin is used, it is difficult to impart ultraviolet resistance and weather resistance as in the case of using a vinyl chloride resin.

  Although the present invention has been described with reference to the most practical and preferred embodiments at the present time, the invention is not limited to the embodiments disclosed herein. However, it can be changed as appropriate without departing from the gist or concept of the invention that can be read from the claims and the entire specification. Manufacturing methods are also to be understood as being within the scope of the present invention.

  The vinyl chloride resin molded product according to the present invention can suppress dripping dirt over a long period of time, and can be particularly suitably used as an exterior member for construction.

Claims (9)

Together comprising a resin composition containing a vinyl chloride resin as a main component, it has a concave-convex shape satisfying all of the following conditions on the surface (a) ~ (c),
The irregular shape is a shape having a prismatic convex portion, a shape having a cylindrical convex portion, a shape having a lattice-shaped convex portion and a rectangular concave portion, or a shape having a corrugated or curved irregular shape, A vinyl chloride resin molded article characterized by being selected from
(A) The uneven pitch (λ) is 500 μm or less (b) The uneven depth (d) is 20 μm or more and 250 μm or less (c) The ratio (λ / d) of the uneven pitch (λ) to the uneven depth (d) is 1 ≦ λ / d ≦ 3   The vinyl chloride resin molded article according to claim 1, which is in a sheet form and has the uneven shape on at least one surface. The vinyl chloride resin molded article according to claim 1 or 2, wherein a content of the vinyl chloride resin in the resin composition is 40% by mass or more and 80% by mass or less. The exterior member using the vinyl chloride resin molded object of any one of Claims 1-3. The exterior member by which a base material is laminated | stacked on the surface side different from the surface which has the said uneven | corrugated shape of the vinyl chloride resin molded object of any one of Claims 1-3. While molding a resin composition containing a vinyl chloride resin as a main component or after molding, the surface satisfies all of the following conditions (a) to (c), and has a prismatic convex shape, a cylindrical shape Characterized in that it comprises a step of providing an uneven shape selected from a shape having a convex portion, a shape having a lattice-like convex portion and a rectangular concave portion, or a shape having a corrugated or curved shape. A method for producing a vinyl resin molded article.
(A) The uneven pitch (λ) is 500 μm or less (b) The uneven depth (d) is 20 μm or more and 250 μm or less (c) The ratio (λ / d) of the uneven pitch (λ) to the uneven depth (d) is 1 ≦ λ / d ≦ 3 The manufacturing method of the vinyl chloride resin molding of Claim 6 which provides the said uneven | corrugated shape in the said surface by the thermal transfer process using an embossing roll or an embossing plate. The manufacturing method of the vinyl chloride resin molded object of Claim 6 or 7 which provides the said uneven | corrugated shape in the sheet | seat surface, after shape | molding the said resin composition in a sheet form. The manufacturing method of the vinyl chloride resin molded object of any one of Claims 6-8 whose content of the said vinyl chloride resin in the said resin composition is 40 to 80 mass%.