JPH0352545B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for industrially forming a green-blue film relatively quickly on the surface of copper or copper alloy products, particularly copper plates for building materials used as roofing materials. be. [Prior Art] Many patent applications have been filed so far for methods of industrially forming a green-blue film on the surface of copper or copper alloy products, particularly copper plates for building materials used as roofing materials. Chemical treatment methods, such as chemical conversion treatment methods, chemical electrolytic treatment methods, chemical conversion treatment and further painting methods, methods of painting with paints containing green-blue-forming substances, and copper surfaces whose surface has been roughened by sandblasting etc. Examples include a method of bonding copper powder or copper alloy powder with an adhesive and then applying a treatment liquid having a patina effect to form a patina film. As a method that falls under the above method,
-110235, JP-A-53-122637, JP-A-53-
122638, JP 55-8490, JP 56-9270, JP 56-30396, JP 57-51468, etc.
In either method, the drying after treatment is done naturally, so the color development tends to vary depending on seasonal factors, such as outside temperature and humidity, or the process of treatment and drying needs to be repeated, so the patina may change. Not only is the color development rate slow, but the green-blue film tends to be uneven and has poor adhesion, which is not necessarily suitable for quality or industrial production. As a method that falls under the above method,
-122641, Special Publication Showa 55-12117, Special Publication Showa 55-14157,
Japanese Patent Publication No. 55-15558 and Japanese Unexamined Patent Publication No. 57-177997 are cited, but although it is possible to generate patina on the copper surface in a short time during the treatment process using an electrolytic method, the formed patina film may peel off. easy things,
It also has problems such as requiring a large amount of capital investment. As applicable to the method of
8491, JP-A No. 56-13483, etc., but they have the problem that it is difficult to stably form a patina film. As applicable to the method of
139467, but it has the problem that adhesion deteriorates due to chocking of the coating film due to aging of the patina film. As applicable to the method of
69375, and Japanese Patent Publication No. 57-52425, but all of these methods require a large number of steps to form a verdigris film, and have problems in terms of productivity and processing cost. In order to solve these problems, the inventor of the present invention has investigated and developed a patina film-forming treatment solution that has the function of promoting patina formation, and after applying and drying the treatment solution, the coating film can be formed in a shorter time. The present invention was completed by discovering a treatment method for promoting patina that produces a uniform and adhesive patina film. [Object of the Invention] The present invention was made with the aim of eliminating the above-mentioned problems and satisfying the needs. After applying it to the surface and forcing it to dry, spray water and/or steam onto the applied surface in an atmosphere controlled at a constant temperature, or
Alternatively, the coated surface is exposed to a relative humidity of 90% or higher to develop a greenish-blue color, and then dried. In other words, in the above surface treatment process, a greenish-blue film with excellent appearance and adhesion is maintained throughout the year at outside temperature and humidity. The object of the present invention is to provide a new method for forming a patina film that is similar to natural patina and is extremely superior in terms of industrial production. [Structure of the Invention] The present invention, which has been made to achieve the above object, comprises a verdigris film forming treatment liquid (hereinafter referred to as treatment liquid) and an accelerated treatment method using the treatment liquid.
In other words, the solid content of water-based resin is 10 to 300g/
, a compound that forms a complex salt with copper ions, a compound that forms a chelate bond with copper ions, and an alkali metal salt in a total amount of 40 to 500 g, and further contains 5 to 4 g of silica, and the processing solution is cleaned. After coating the surface of copper or copper alloy and forcing the coated surface to dry, the coated surface is sprayed with water and/or steam to develop color, or the coated surface is kept at relative humidity.
By exposing the coated surface to an atmosphere of 90% or more to develop the color and then drying the coated surface, a green color with an excellent appearance and excellent adhesion, which is uniform on copper or copper alloy and has a subdued color tone close to natural patina. It consists of a treatment method that can form a blue film. [Description of Composition and Conditions] The water-based resin contained in the treatment liquid used in the present invention may be either water-soluble or water-dispersible, and the types of resin include acrylic, alkyd, urethane, Commonly used resin compositions such as polyester-based resin compositions are applicable. The resin content in the treatment liquid is preferably 10 to 10% in terms of solid content.
300g/particularly preferably 50-200g/.
A patina film formed with a treatment liquid containing less than 10 g/g/ml has poor adhesion. In addition, it was not possible to prepare a treatment liquid containing more than 300 g/ml because the solid content of the aqueous resin used in the examples of the present invention was lower than 50%, so the performance could not be confirmed. This is not preferable because it increases the cost. Substances that form complex salts with copper ions include aqueous ammonia, ammonium salts, and amines; substances that chelate with copper ions include polyaminocarboxylic acid salts such as ethylenediaminetetraacetate, oxycarboxylic acids such as citric acid, and condensation Examples include phosphates, and any of these substances can be selected and used. Examples of alkali metal salts include sodium, potassium, and lithium salts of hydrochloric acid, sulfuric acid, and acetic acid. The content of these compounds in the treatment solution is preferably 40 to 500 g/, particularly preferably
It is 100-400g/. If the treatment solution has a content of less than 40 g/l, the amount of dry coating obtained by coating will be small and the patina will be insufficient or will not progress much. A treatment solution with a content of more than 400 g/ml has the ability to sufficiently turn the film into a patina, but as a prerequisite for this, the content of water-based resin must be reduced, which results in a decrease in adhesion. Undesirable. The concentration of the substance forming a complex salt with the copper ion is preferably 20 to 480 g/, and the concentration of the substance forming a chelate bond with the copper ion and the alkali metal salt is preferably 10 to 470 g/. As the silica, commercially available colloidal silica or finely powdered silica can be used. The content of silica is preferably 5 to 5.
40g/particularly preferably 10 to 30g/, and 5
If the amount is less than 40g/, the uniformity of the coating will decrease and it will not contribute enough to improving the color development, and if the amount is more than 40g/, the adhesion of the film will decrease. Even so, I don't like it. Next, methods for applying the treatment liquid according to the present invention include, for example, spray coating, roll coater coating, air knife method, curtain flow coater method, etc., but these methods are not particularly specified. Any coating method may be used as long as it can uniformly apply the treatment liquid to the surface of the substrate at a dry adhesion amount of 5 to 30 g/m ² . When the dry adhesion amount is less than 5 g/m ² , patina formation is difficult to occur, and when it is more than 30 g/m ² , the adhesion of the formed patina film decreases and the consumption of processing solution increases. Therefore, it is unfavorable in terms of performance and cost. Examples of forced drying means include methods using hot air or infrared rays. Although these methods are not specified, the drying conditions are usually 100~
200℃ (60 to 130 as the plate temperature of copper or copper alloy coated plate)
The test is carried out under the conditions of fixation and drying at a temperature of In addition, the main point of the green-blue formation promotion treatment method in the present invention is to apply moisture as uniformly as possible to the dry film obtained in the above treatment and quickly react with the surface of copper or copper alloy. Preferably, a method of spraying water in the form of mist or steam onto the coated plate, or a method of exposing the dried film to a high humidity atmosphere is preferred. In the method of spraying water in the form of a mist, it is desirable to spray the mist as finely and uniformly as possible. Color development is promoted when the ambient temperature is high to a certain extent, but when processing costs are taken into consideration, room temperature to about 80℃ (particularly preferably about 30 to about 60℃)
is appropriate, and in order to keep the color tone constant, it is preferable to keep the temperature as constant as possible. The appropriate spray amount is 1 to 12 ml/m ² /min (especially preferably about 2 to about 5 ml/m ² /min), and 1 ml/m ² /min.
If it is less than this, it will take too long for color development (greenish-blue) and unevenness in greenish-blue shade will likely occur. Also 12ml/m ² /
If it exceeds min, color flow becomes uneven, which deteriorates the quality of the patina film after drying, which is not preferable. A treatment time of about 5 to about 120 minutes (particularly preferably about 20 to 60 minutes) is practically and productively appropriate.Actually, the treatment time should be selected appropriately depending on the green-blue condition and the treatment should be carried out for a certain period of time. It is preferable to do so. Next, the practical method of exposing the coated surface to a high humidity atmosphere is to expose it to an atmosphere at room temperature to about 80℃ (especially preferably about 30 to about 60℃) and relative humidity of 90% or more for about 30 to about 120 minutes. This is preferable considering the following. The copper or copper alloy material that has been subjected to the above acceleration treatment is either dried as is or washed with water and then dried. Either natural drying or forced drying may be used as the drying method, but since changes in drying conditions will cause subtle changes in the green-blue tone, select drying conditions that match the color tone and maintain the conditions within a constant range as much as possible. There is a need. However, forced drying is preferred for industrial production. The forced drying temperature is usually preferably about 100 to about 200°C (about 80 to about 130°C as the temperature of the treated plate). A clear coat may also be applied on the resulting patina film to further strengthen and protect the surface. The clear coating agent may be a commonly used water-based, solvent-based or resin-based one, and is not particularly limited thereto. [Function] The treatment liquid in the present invention can form a green-blue film by being exposed outdoors for about one month after applying and drying the treatment liquid, so it itself has the function of promoting green-blue color. The present invention also includes a method of accelerating the formation of patina during the treatment process. That is, the film formed by applying a treatment solution to a surface-clean copper or copper alloy surface and forcing it to dry has air permeability and water permeability, so this coating film is coated with the patina promotion treatment of the present invention. That is, water and/or steam spray or room temperature to about 80°C,
By exposing the material to an atmosphere having a relative humidity of about 90% or higher, a verdigris film can be formed in the verdigris film formation promotion treatment process of the present invention. In other words, when accelerated treatment is performed after applying and drying a treatment liquid, moisture penetrates into the film, and the components present in the film that develop a greenish-blue color, i.e., compounds that form complex salts with copper ions, copper ions. Dissolve the compound and alkali metal salt that chelate with. The aqueous solution containing this color-forming component ionizes copper on the surface, forms a copper complex salt and a copper chelate compound with the ionized copper, and develops a greenish-blue color. At this time, alkali metal salts play a role in promoting this reaction.
These substances are soluble, but as they dry after the coloring treatment and over time, insoluble basic copper chloride further progresses to form a stable patina film. The patina film thus formed is uniform and has excellent adhesion, combined with the adhesion-improving effect of resin, silica, etc. coatings, and becomes a patina film that approximates a settled natural patina. Furthermore, the resulting patina film can be further strengthened and protected by further applying a clear coat on top of the patina film. EXAMPLES Examples of the present invention will be shown below together with comparative examples to specifically explain the effects of the present invention. Example 1 (1) Compounds used in the preparation of treatment liquids The compounds used in the preparation of treatment liquids used in the examples and comparative examples of the present invention are as follows. ●Compounds that form complex salts with copper ions Ammonium chloride (1st grade reagent) Ammonium carbonate (1st grade reagent) ●Compounds that form chelate bonds with copper ions Tetrasodium ethylenediaminetetraacetate (EDTA-4Na, 1st grade reagent) ●Water-based resin Phthalkyd w-760A Resin Solid content 47
% (Alkyd emulsion, Hitachi Chemical
(manufactured by Nippon Aerosil Co., Ltd.) ●Alkali metal salt Sodium chloride (first grade reagent) ●Silica Finely powdered silica (Aerosil #200 Nippon Aerosil Co., Ltd.) (2) Preparation of treatment solution Add the calculated amounts of copper complex-forming compounds and copper chelate-forming compounds. After adding it to an appropriate amount of water and stirring well, silica was dispersed, a calculated amount of water-based resin was added to this water suspension, water was added to bring the total volume to 1, and the treatment solution was prepared by further stirring. . Table 1 shows the composition of the treatment liquid used in the Examples and Comparative Examples of the present invention. (3) Test plate Copper plate for roofing material Thickness 0.35m Dimensions 70mm x 150mm (4) Treatment method Test plate with Perco Cleaner N364S (Alkali cleaner manufactured by Nihon Parkerizing Co., Ltd.) 20
After spray cleaning at 60°C for 1 minute, wash with water, drain and dry. Next, the treatment solution was applied to the test plate at a rate of 40 ml/m ² using a grooved rubber roll coater, and immediately forced drying was performed at 120° C. for 30 seconds. next,
The coated plate was sprayed with water at an ambient temperature of 40℃ for 30 minutes (spray amount 2ml/m ² /min), and then heated to 120℃ for 30 minutes.
Force dry for seconds. Table 2 shows the results regarding the uniform application, green-blue color development, and adhesion of these treatment solutions. (5) Test method and evaluation method Visual observation of treatment liquid applicability ◎...Appearance is uniform ○...There are uneven areas △...Uneven areas are noticeable ×...Applying is uneven overall Visual observation of green-blue color development◎...Over the entire surface Uniformly colored green-blue. ○…There are some uneven parts. △...Color development is weak or uneven. x: Almost no color development is observed. Adhesion After color development, the test plate is coated with the same thickness as the test plate (0.35
Stack 4 sheets of mm) and fold them so that they are sandwiched together. Then, the state of peeling of the film at the bent portion was visually observed. ◎...No peeling at all. ○: Slight peeling is observed. ▲…Approximately 25% peeling is observed. △...Approximately 50% peeling is observed. ×…Full surface peeling.

【table】

【table】

[Table] Looking at the processing solution coating properties, green-blue coloring properties, and adhesion of Examples and Comparative Examples, the addition of resin improves adhesion, and the addition of silica improves coating uniformity and coloring properties. is recognized. In the case of Example 1-5, the adhesion is one rank inferior to Examples 1-2 to 1-4, but this is due to the content of ammonium chloride, ammonium carbonate, sodium chloride, etc. as seen in Table-1. This is because there are relatively many. However, when compared comprehensively, the example is clearly superior. In other words, when promoting patina treatment, there is a mutual effect of a copper complex forming compound, a copper chelate forming compound, an alkali metal salt, an aqueous resin having an adhesion function, and silica that improves uniform application, and providing moisture to the coated surface. The combination of these effects makes it possible to form a patina film with a calm tone in a short period of time, uniformly and with good adhesion. On the other hand, Comparative Examples 1-1 to 1-3
Since the applied treatment liquid does not contain a water-based resin, the color development is excellent, but the adhesion is significantly inferior. Furthermore, Comparative Examples 1-5 had a very low silica content, resulting in poor color development and poor uniformity during coating. Next, in Comparative Example 1-4, the silica content was too high, so the adhesion was reduced. Also, Comparative Example 1-6
is because the total amount of copper complex-forming compounds, copper chelate-forming compounds and alkali metal salts is insufficient.
Almost no green-blue color was observed. In short, contradictory phenomena occur: adding resin to improve adhesion will result in poor color development, and adding too much silica to improve color development will result in poor adhesion. This makes it possible to improve adhesion and color development at the same time. Example 2 A method of promoting patina color development was investigated on a copper plate treated by the coating method of Example 1 using treatment solution 1-4 of Example 1. The conditions and results are shown in Table 3. . The test method and evaluation method are the same as in Example 1.

[Table] From the results in Table 3, it can be seen that the examples exhibit better color development than the comparative examples. That is, while the patina is promoted by supplying moisture to the film under the conditions shown in Example 2, Comparative Example 2
In the case of -1, color development is insufficient due to insufficient water supply, and in the case of Comparative Example 2-2, the patina film runs and becomes uneven due to excessive water supply, resulting in poor appearance. Moreover, in the case of Comparative Example 2-3, the green color development was extremely poor due to the low humidity in the atmosphere. [Effects of the Invention] As explained above, the method for promoting the formation of a verdigris film according to the present invention involves forming a film containing a predetermined amount of a water-based resin, an alkali metal salt, and silica, and then adding 50% water and/or water vapor to the film. ~60 minutes spray or humidity
Because it develops a greenish-blue color by exposing it to 90% or more for 30 to 120 minutes, even if the film is 5g/ ^m2 or more, it can quickly form a greenish-blue film with a calm color tone and improve its adhesion. It produces excellent results and allows for easy formation of excellent products. Furthermore, when a roof is constructed using a copper plate treated by the method of the present invention, it is possible to obtain a roof that has a uniform and subdued green-blue color immediately after construction, and the resulting patina film has a natural patina. It also has excellent effects such as being similar and preferable in terms of quality.

Claims (1)

[Claims] 1. 10 to 300 g of water-based resin as solid content,
A treatment solution containing a total of 40 to 500 g of a compound that forms a complex salt with copper ions, a compound that forms a chelate bond with copper ions, and an alkali metal salt and 5 to 40 g of silica is applied to the surface of a clean copper or copper alloy. After coating and force drying to form a film of 5 to 30 g/ ^m2 , water and/or steam is sprayed on the coated surface for 5 to 120 minutes to develop a green-blue color, and then the coated surface is dried. A treatment method for promoting the formation of a verdigris film. 2. The method for promoting the formation of a verdigris film according to claim 1, which comprises spraying water and/or steam in an atmosphere at room temperature to 80°C. 3 Spray water and/or steam at a rate of 1 to 12 ml/m ² /
The method for promoting the formation of a verdigris film according to claim 1, which is carried out at a rate of min (amount of spray per minute per square meter, in the case of water vapor, its water equivalent value). 4 10 to 300 g/solid content of water-based resin,
A processing solution containing a compound that forms a complex salt with copper ions, a compound that forms a chelate bond with copper ions, and an alkali metal salt in a total amount of 40 to 500 g/, and further contains 5 to 40 g/of silica, is used to clean copper. Alternatively, apply it to the surface of a copper alloy and force dry the coated surface to form a film of 5 to 30 g/ ^m2 , and then leave the coated surface in an atmosphere of room temperature to 80°C and relative humidity of about 90% or more for 30 to 30 minutes. 1. A treatment method for promoting the formation of a green-blue film, which comprises exposing the coated surface for 120 minutes to develop a green-blue color, and then drying the coated surface. 5. Claim 4, which develops a greenish-blue color by exposing it to an atmosphere of 30 to 60°C and a relative humidity of about 90% or more.
The method for promoting the formation of a verdigris film as described in .