JP2008297413A - Water-based coating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-based coating for wood which is free of an organic solvent as a solvent for an oil and fat and having high safety for human bodies and performances equal to those of a solvent type oil-based coating. <P>SOLUTION: The water-based coating is composed of an aqueous dispersion made from a vegetable oil as a raw material and an additive. The aqueous dispersion is obtained by emulsifying 100 pts.wt. of an oil and fat composed of a processed oil obtained by treating the vegetable oil (except the oil in which an organic solvent is added) in water with 3.3-15 pts.wt. of a surfactant. The oil and fat used herein is a film-forming component and is the processed oil obtained by treating the vegetable oil (except the oil in which the organic solvent is added). The vegetable oil is an oil collected from a plant and a drying oil or a semi-drying oil is used. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a water-based paint for wood using vegetable oil as a raw material.

  There are oil-based and water-based types of paint for wood. The oily type has been used for a long time, has good permeability to wood, and forms a coating film that follows the expansion and contraction of wood after drying. The conventional oily type uses an organic solvent as a solvent for the oil and fat to be the coating film component.

  In recent years, reduction of volatile organic compounds (VOC) has been demanded from the viewpoint of air pollution and handling safety, and the paint industry is also researching and developing to bring volatile components close to zero. .

  As a method for reducing the volatile organic solvent, a method (emulsification) of dispersing fats and oils (coating film component of paint) in water without using an organic solvent as a solvent can be considered. Such a water-dispersed paint is one solution for reducing volatile organic solvents.

  The coating film performance and finish feeling of the paint mainly depend on the coating film component (resin containing fats and oils). In the case of an oxidative curable paint using an oil-based resin, the resin is chained and gradually cured by taking in oxygen in the air when the solvent evaporates and dries. Therefore, a coating film with moderate hardness and elongation is completed.

  This oil-based paint penetrates and adheres well to wood, and can protect wood for a long time. However, the disadvantages of solvent-based oil-based paints are that the solvent odor is harsh, and that organic solvents must be used to clean the paint tools after the painting operation is completed. Organic solvents contain a large amount of harmful components for humans and the above-mentioned air pollutants. In recent years, water-based paints have been actively developed in all fields including industrial paints.

  Development of water-based paints has also progressed, and with synthetic resin emulsion paints in which synthetic resin is dispersed in water, it has become possible to obtain finishes and coating film performance comparable to conventional solvent-type synthetic resin paints. However, in the field of wood coatings, synthetic resin emulsion paints do not provide a finish that enhances the beauty of the grain of traditional oil finishes.

  In addition, even if a weather-resistant water-based paint (for example, acrylic emulsion, urethane dispersion, silicone-modified acrylic emulsion, etc.) currently marketed for outdoor wood parts is used, the weather resistance does not reach that of oil-based paints. . Even if outdoor weather resistance is good, if maintenance coating is performed after several years after painting, considerable effort is required to peel off the old coating film. On the other hand, since the coating film gradually flows down with the passage of time, the surface of the oil-based coating can be repeatedly applied by washing the surface when the coating film becomes thin.

  With regard to recent synthetic resin emulsion paints, considering a resin dispersed in water, fine particles already polymerized are dispersed in water. Therefore, a coating film is formed by fusing fine particles with a film-forming aid (mostly a high-boiling solvent) blended in the paint as the water evaporates after coating. For this reason, the permeability with respect to wood is inferior compared with an oil-based paint. Moreover, even if the weather resistance of the coating film is strong, in the case of wood, unlike metal and other inorganic materials, it is weak against ultraviolet rays because it is organic, and ultraviolet rays deteriorate the surface of the wood through the coating film. Therefore, the boundary surface between the coating film and the wood becomes weak, and the coating film peels off from the wood no matter how strong the coating film is. Therefore, synthetic resin emulsion paints are not suitable for painting wood for outdoor use.

  The good point of water-based paint is that it is easy to handle, and after painting work, the painting tool can be washed with detergent and water, and no organic solvent is required from the paint stage to the work after painting. Therefore, there is almost no odor resulting from the volatile organic solvent.

  The present invention combines the advantages of solvent-based oil-based wood paints (wood permeation is good and difficult to peel off) and water-based wood paints (safe without using organic solvents as oil solvents). Related to wood paint. Furthermore, since vegetable oil is used as a raw material as a coating film component, it is related to the one with higher safety.

As a water-dispersed wood coating material made of vegetable oil as a raw material, those disclosed in the following Patent Document 1 are known.
JP 56-26964 A

  This patent document 1 relates to a wood emphasis agent that protects wood and gives an aesthetic appearance. This wood emphasis agent is obtained by emulsifying a dry oil or semi-dry oil and a solid wax as main components in water. Nonionic interface by adding 100 parts by weight of linseed oil, safflower oil, tung oil, soybean oil, etc. to 1 part by weight of solid wax such as paraffin wax in an organic solvent as a water repellent. The water dispersible wood emphasis agent is obtained by emulsifying in 5 to 20 parts by weight of the activator. Since this wood emphasis agent is a water-dispersed liquid, it does not have to worry about fire or poisoning due to organic solvents, and is easy to immerse, apply, spray, etc., and has excellent workability. However, since the solid wax is dissolved in the organic solvent, it is not possible to eliminate the organic solvent.

Moreover, the following patent document 2 is known as suggesting the water dispersible wood coating material which uses vegetable oil as a raw material.
JP 2004-26994 A

  This Patent Document 2 relates to an emulsion of oils or waxes, and an emulsion is obtained by adding oils or waxes to alkaline water generated by electrolysis of water and stirring with heating. Oil emulsions are particularly suitable for exhaust gas purification (passing exhaust gas through the emulsion), and wax emulsions are particularly suitable for coating agents. In Patent Document 2, as oils, cypress essential oil, tea seed oil, olive oil and the like, which are vegetable oils, are exemplified. Moreover, the protection of wood is mentioned as a use of a coating agent.

  The above-mentioned Patent Document 1 discloses the use of an aqueous emulsion containing vegetable oil as a wood protective agent. However, since a solid wax dissolved in an organic solvent is added as a water repellent and emulsified, It has not been possible to eliminate the organic solvent. When a wax is blended, there is a temporary water-repellent effect, but the weather resistance is not good, so it is not possible to maintain long-term performance in terms of weather resistance. Patent Document 2 discloses an emulsion of vegetable oil and alkaline water, and suggests a coating agent for wood as its use, but the blending ratio of vegetable oil and water when used as an aqueous paint for wood. No mention is made of the presence or absence of surfactants and their proportions.

  An object of the present invention is to provide an aqueous paint for wood that does not contain an organic solvent as a solvent for fats and oils, has high safety for the human body, and has performance equivalent to that of a solvent-type oil paint. Another object of the present invention is that the amount of solvent reduction is large, which contributes to the reduction of environmental pollution, is excluded from the handling of dangerous goods under the Fire Service Act from the viewpoint of handling, and is safer against fire than solvent-based paints. An object is to provide an improved water-based paint for wood.

  The water-based paint for wood of the present invention comprises an aqueous dispersion made from vegetable oil and an additive. The aqueous dispersion is obtained by emulsifying 100 parts by weight of fat and oil consisting of processing oil (excluding those to which an organic solvent is added) processed from vegetable oil in water using 3.3 to 15 parts by weight of a surfactant.

  Additives suitable for waterborne paints for outdoor wood are antiseptics, freeze stabilizers, wetting agents, fungicides, insect repellents and drying accelerators. Additives suitable for waterborne paints for indoor wood are preservatives, freeze stabilizers, wetting agents, drying accelerators and surface conditioners. In order to obtain a colored paint in water-based paints for outdoor wood parts and indoor wood parts, a color paste adjusted to be dispersed in water is used as an additive.

  The fats and oils used in the present invention are coating film forming components and are processed oils (excluding those added with an organic solvent) processed from vegetable oils. The vegetable oil is an oil collected from a plant, and a dry oil or a semi-dry oil is used. The dry oil has an iodine value of 130 or more, and examples thereof include Chinese tung oil, linseed oil, Japanese paulownia oil, cocoon oil, and hemp seed oil. Semi-drying oils have an iodine value of 100 to 130, and include sesame oil, soybean oil, safflower oil, cottonseed oil, rice bran oil, tall oil and the like. Processed oil processed with vegetable oil (excluding those added with organic solvent) is one that has been heated to increase the degree of polymerization or added with a desiccant (dryer) in order to increase the drying property of the vegetable oil. It is. In the present invention, the processing oil to which an organic solvent is added is excluded. Examples of processed oils processed from vegetable oil include boiled linseed oil (with increased degree of polymerization and addition of metal oxide desiccant), dehydrated castor oil polymerized oil (dehydrated castor oil and oxidized to dryness) Processed). In addition, there is a polymer oil of each vegetable oil.

  The surfactant used in the present invention plays a role of dispersing the above-mentioned fats and oils in water. This surfactant is preferably a nonionic one. The nonionic system is most excellent in the stability of water-based paints when “color paste adjusted to be dispersed in water” and other additives are added to the aqueous dispersion. The following can be used as the nonionic surfactant. (A) As alkyl ether type, polyoxyethylene alkyl ether, polyoxyethylene 2-ethylhexyl ether, polyoxyethylene oleyl ether, polyoxyethylene tridecyl ether, polyoxyethylene castor oil ether, polyoxyethylene cetyl ether, polyoxy Ethylene stearyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyldodecyl ether, polyoxyethylene cholesteryl ether, polyoxyethylene decyl tetradecyl ether, polyoxyethylene behenyl ether , Polyoxyalkylene alkyl ether, lauryl alcohol alkoxylate, lauryl Le call ethoxylates, primary alcohol ethoxylates. (A) Polyoxyethylene polycyclic phenyl ether as polycyclic phenyl ether type. (C) As sorbitan derivatives, sorbitan stearate, sorbitan oleate, sorbitan trioleate, sorbitan monourarate, sorbitan sesquioleate, polyoxyethylene sorbitan stearate, polyoxyethylene sorbitan monooleate, polyoxyalkylene sorbitan fatty acid ester . (D) As an EO / PO block polymer, a polyoxyethylene / polyoxypropylene block polymer. (E) Others include polyoxyethylene oleate, polyoxyethylene triisostearate trimethylolpropane, polyoxyethylene hydrogenated castor oil, polyoxyethylene glyceryl tristearate, triglyceride glyceryl, and polyethylene glycol monoisostearate.

  As for the ratio of fats and oils, surfactant is 3.5-15 weight part with respect to 100 weight part of fats and oils. When the surfactant is less than 3.5 parts by weight, the dispersed particles become coarse and the stability of the emulsion is deteriorated. On the other hand, when the surfactant exceeds 15 parts by weight, the surfactant acts as a plasticizer, lowers the hardness of the coating film, increases hydrophilicity, and decreases water resistance. Furthermore, when the amount of the surfactant is excessively large, it does not dry. The upper limit of the amount of the surfactant is about 15 parts by weight.

  Depending on the type of oil and fat used, select the type of nonionic surfactant (select one or more composites) and make quantitative adjustments to obtain a homogeneous and stable aqueous dispersion. Obtainable.

  The ratio of fats and oils to the total weight of the water-based paint is preferably 10 to 50% by weight. The optimum ratio of fats and oils depends on the type of fats and oils. For example, in the case of polymerized oil of dehydrated castor oil, an aqueous dispersion containing 30 to 50% by weight of fats and oils is stable. In China tung oil-polymerized oil, an aqueous dispersion containing 30 to 50% by weight of fats and oils is stable.

  The water used in the present invention is preferably ion exchange water. Distilled water can also be used. Although tap water can be used depending on circumstances, it may contain iron or calcium, so that the particle size of the water-dispersed particles may be uneven or the stability may be impaired.

  Various additives can be added to the aqueous dispersion described above. In order to enhance the drying property, a drying accelerator (for example, a metal dryer) can be added. In order to adjust the color of the paint, a color paste adjusted to be dispersed in water can be added. Preservatives can be added to provide long-term storage. Freezing stabilizer can be added to prevent freezing in winter. An antifoaming agent can be added so as not to generate bubbles during production and coating. A fungicide or insect repellent can be added for the purpose of fungicide or insect repellent. In order to enhance durability against ultraviolet rays, an ultraviolet cut agent can be added. A surface conditioner can be added to improve the feel of the painted surface. A wetting agent can be added for the purpose of improving the wettability and dispersibility, arranging the emulsion particles, and preventing precipitation of the pigment. These additives are appropriately selected depending on whether they are for outdoor xylem or indoor xylem. Preservatives, freeze stabilizers, wetting agents, fungicides, insect repellents, UV screening agents and drying accelerators are added to the waterborne paint for outdoor wood. Preservatives, freeze stabilizers, wetting agents, drying accelerators and surface conditioners are added to the waterborne paint for indoor wood. In addition, in the case of a colored paint in the water-based paint for outdoor wood parts and indoor wood parts, a color paste adjusted so as to be dispersed in water is further added.

  Since the water-based paint for wood of the present invention uses only vegetable processing oil as the fat and oil, and does not use the organic solvent as the fat and oil solvent, it is an emulsion using water. Safe and less environmental pollution. Moreover, although it is a water-based paint, the permeability with respect to wood is favorable. Compared with the conventional paint, it is as follows. Wood paints composed of synthetic resin emulsions contain a small percentage of organic solvents and have less environmental pollution, but are poorly permeable to wood. On the other hand, a solvent-based wood paint in which a coating film component is dissolved in an organic solvent has good permeability to wood, but has problems in terms of safety to the human body and environmental pollution. On the other hand, the water-based paint of the present invention has a permeability equal to or better than that of a solvent-based paint, is safe for the human body, and can reduce environmental pollution.

  Considering the coating for outdoor wood (wood protective coating), this is generally divided into three types: a film-forming type, a permeation type, and a semi-film-forming type (between the film-forming type and the permeation type). In the film-forming type paint, the coating film peels off as the coating film deteriorates. On the other hand, since the penetration type paint does not peel off the coating film, the maintenance is easy. The water-based paint of the present invention is a penetrating type and is superior to the film-forming type in this respect. The commercially available waterborne outdoor xylem paints are a film-forming type and a semi-film-forming type, and there is no penetrating type. In addition, when compared with a conventional paint for outdoor xylem, when the water-based paint of the present invention is used for outdoor xylem, it is a penetrating type and does not contain an organic solvent. Better than. In the conventional type, the permeation type contains an organic solvent, and the one not containing the organic solvent is a film-forming type or a semi-film-forming type.

  When the water-based paint of the present invention is used as a paint for indoor wood parts, it exhibits a wood part permeability and finish performance equivalent to or higher than a solvent-type penetrating paint called teak oil, although it is an aqueous paint.

  The aqueous paint of the present invention is characterized by an aqueous dispersion of vegetable oil. A biaxial stirrer is used to make this aqueous dispersion. This stirrer includes a stirring blade that can obtain a shear flow at a high speed (about 1000 rpm) and a low-speed stirring blade for high viscosity (wall scraping blade). As the stirring liquid becomes higher in viscosity, a dead space tends to be formed in the vicinity of the wall surface in the pot of the stirrer, and the fluidity of this part decreases. In the biaxial agitator, the dead space in the vicinity of the wall surface is scraped with a low-speed arm-type blade, so that the fluid in the vicinity of the wall surface can be guided to the central portion to be uniformly stirred. Thereby, stirring of a wide viscosity range can be performed efficiently. Since the aqueous dispersion used in the present invention does not use a solvent, it becomes highly viscous at the emulsification stage. Therefore, the emulsifying apparatus usually used does not work. For example, as a general device for emulsification, there are a high-speed rotating stirrer (homogenizer) and a device that sprays from a nozzle while being pressurized by a high-pressure pump. It can be used only for emulsification. Since the aqueous dispersion used in the present invention temporarily has a high viscosity, the above-described biaxial stirrer is used for stirring.

  Appropriate temperature control is required to make a stable aqueous dispersion. It is necessary to keep the temperature during emulsification within a certain range so as not to impair the properties of the surfactant used for emulsification. It is necessary to keep the temperature during emulsification within the range of 15 to 65 ° C.

  An example of a method for producing an aqueous dispersion containing fats and oils will be described below by taking, as an example, processed oil of Chinese paulownia oil as the fats and oils. In the case of an aqueous dispersion having a production amount of 20 kg and an oil and fat content of 30% by weight, it is produced as follows. Nonionic surfactant (polyoxyethylene alkyl ether) and ion-exchanged water are uniformly mixed at a ratio of 30:70. The processing oil of Chinese paulownia oil is adjusted to a temperature of 20 to 30 ° C. and an amount of 6 kg is put into a tank of a biaxial agitator. The above-mentioned mixed solution of the surfactant and ion-exchanged water is adjusted to a temperature of 15 to 30 ° C., and an amount of 1.33 kg is put into the tank of the biaxial agitator. Set the blades of the twin-shaft stirrer to the optimal position, and then start stirring. After a few minutes, the viscosity increases as the above-mentioned mixed solution and fats and oils are mixed. Finally, the fluidity is lost and a cream is formed. In this state, stirring is continued for 20 to 30 minutes. The tank is cooled to control the temperature so that the temperature during stirring does not exceed 60 ° C. Next, during the stirring, an amount of 2 kg of ion exchange water is added at a flow rate of 100 g / min. Further, the remaining 10.67 kg of ion-exchanged water is added at a flow rate of 300 g / min, and an aqueous dispersion having a fat and oil content of 30% by weight is completed. A freezing stabilizer, an antiseptic and an antifoaming agent are added to the aqueous dispersion to complete an aqueous paint base for evaluation.

  In contrast to the aqueous paint base for evaluation obtained in this way, the waterborne paint for outdoor wood parts includes a wetting agent, a fungicide, an insecticide, a color paste adjusted to be dispersed in water, An ultraviolet blocking agent and a drying accelerator (metal dryer) were added. Wet agents, surface conditioners, and drying accelerators (metal dryers) were added to the waterborne paint base for indoor wood parts. In the case of a water-based colored paint for indoor wood, a color paste adjusted to be dispersed in water was further added.

  When the time-dependent stability of the water-based paint for evaluation thus obtained was evaluated, the freezing cycle (which was held at minus 15 ° C. for 8 hours and then held at 25 ° C. for 16 hours) was executed for 3 cycles. However, no particular quality problem occurred. Further, even in the accelerated test for 3 months at 50 ° C., which was assumed to be stored in summer, and the test stored for 12 months at room temperature, there was no problem in quality and it was stable.

  The water-based paint for evaluation obtained as described above has very fine particles in which the particle size of the oil and fat particles dispersed in water is about 0.3 μm. By using this as a coating material, the wood has good permeability and a finish that makes the most of the texture of the wood can be obtained.

  The water-based paint of the present invention is a paint specialized for wood. This water-based paint has good adhesion to wood. However, since this water-based paint uses only processing oil obtained by treating vegetable oil as a coating film component, it is difficult to obtain a smooth coating film and is not suitable for materials lacking permeability (glass, metal, plastic, etc.). .

<Example 1>
Put non-surfactant surface activity against 30 parts by weight of cinna tung oil polymer oil while putting it into a biaxial stirrer. 2 parts by weight of an agent (polyoxyethylene alkyl ether) was added (surfactant was 6.7 parts by weight based on 100 parts by weight of fats and oils). After stirring for 15 minutes, 10 parts by weight of ion-exchanged water was dropped during stirring, and stirring was continued for 10 minutes even after the dropping. Thereafter, 100 ppm of an antifoaming agent (silicone oil emulsion) was added to the polymer oil of cinnamon oil, and then 58 parts by weight of ion-exchanged water was added and stirred. Thereby, the adjustment liquid whose oil-fat density | concentration is 30 weight% was obtained. This adjustment liquid is equivalent to what added the antifoamer to the aqueous dispersion liquid which consists of fats and oils, surfactant, and ion-exchange water. 5 parts by weight of a color paste adjusted so that an inorganic pigment is dispersed in water, 0.3 part by weight of a drying accelerator (cobalt, manganese, zirconium), and an ultraviolet absorber with respect to 100 parts by weight of the adjustment liquid 1 part by weight of an aqueous dispersion and 1 part by weight of an insect and fungicide (an aqueous dispersion of an isothiazoline compound) were added to prepare a trial paint 1. This prototype paint 1 is an aqueous paint for outdoor wood parts.

  The prototype paint 1 can be applied by the following procedure. (1) Wood adjustment. Polish the wood surface with 80-150 polishing paper. When the prototype paint 1 is repainted, the old coating film is washed with water, dried and then polished. (2) Apply once. Apply a brush so that the application amount is 80 to 100 g per square meter. At that time, the brush should be sufficiently filled with paint. (3) Drying. Let stand for 24 hours to dry. Check the dryness before moving on to the next two coats. (4) Apply twice. Apply a brush to apply 50-70 g per square meter. At that time, it is uniformly applied so as not to cause uneven color. (5) Drying. Let stand for 24 hours to dry. Thereafter, the dry state is confirmed.

  An application test was conducted on the trial paint 1 and two comparative paints. The comparative paint 1 is a solvent-type oil-based paint, and is a commercially available solvent-type outdoor wood part paint mainly composed of an oil-modified urethane resin. The comparative paint 2 is an emulsion type (emulsion type) water-based paint, and is a commercially available outdoor xylem paint mainly composed of an acrylic emulsion. For prototype paint 1 and two comparative paints, they were applied twice to the surface of rice cedar (aka Western Red Cedar) so that the total application amount was 150 g per square meter, and exposed to the south surface outdoors. . The test results are shown in Table 1.

  Regarding the deterioration of the coating film, the comparative paint 2 caused peeling of the coating film in less than one year. In the trial paint 1 and the comparative paint 1, no peeling of the coating film occurred even after 2 years and 6 months. In Table 1, when the volatile organic compound (VOC) which is a main evaluation item and the wood permeability are examined, the comparative paint 1 has good permeability, but the volatile organic compound (VOC) is 70 to 80%. Many. Although the volatile organic compound (VOC) of the comparative paint 2 is as small as 5 to 10%, the wood permeability is inferior (the coating film is easily peeled off). On the other hand, the trial paint 1 has a low volatile organic compound (VOC) of 1% or less and good permeability.

  The volatile organic compound (VOC) in Table 1 will be described. According to the chemical substance classification proposed by WHO, an organic solvent having a boiling range of 50 to 260 ° C. corresponds to a volatile organic compound (VOC). In Table 1, the volatile organic compound (VOC) of the trial paint 1 is “1% or less” and is not “0%” for the following reason. The water-based paint of the present invention comprises only a processing oil of vegetable oil as a coating film component, which is characterized by being dispersed in water using a surfactant, and an organic solvent as a solvent for dissolving fats and oils Is not used at all. Therefore, the volatile organic compound (VOC) as the organic solvent is 0%. However, various additives to be blended when producing the final paint may contain organic substances that meet the above-mentioned definition of volatile organic compounds (VOC). For example, propylene glycol used as a freezing stabilizer is an extremely safe glycol that is also used in toothpastes and foods. However, when viewed from the boiling range, it corresponds to a volatile organic compound (VOC). In consideration of the volatile organic compound (VOC) derived from such additives, in Table 1, the volatile organic compound (VOC) of the trial paint 1 is not “0%” but “1% or less”. Yes.

<Example 2>
Using the aqueous dispersion of the polymer oil of Chinese paulownia oil prepared in Example 1 as described above as the adjustment liquid, the transparent organic pigment was adjusted to be dispersed in water with respect to 100 parts by weight of the adjustment liquid. Add 1 part by weight of a color paste, 0.3 part by weight of a drying accelerator (cobalt, manganese, zirconium) and 0.1 part by weight of a surface conditioner that gives performance to improve the touch feeling, Produced. This prototype paint 2 is a water-based paint for indoor wood (water-based paint for oil finishing).

  This prototype paint 2 can be applied by the following procedure. (1) Wood adjustment. Polish the surface of wood with 240-320 sandpaper. (2) First application. The paint is applied so that the application amount is 100 to 130 g per square meter, and before being dried, it is sharpened with steel wool No. 00 or nylon abrasive cloth No. 400. Polishing the shaved wood with paint will remove the fluff, and the sharpened residue will be rubbed into the wood for a smooth finish. (3) Drying. Let stand for more than 16 hours to dry. (4) Polishing. Lightly polish with steel wool 00 or 400 sandpaper. (5) Second application. Apply the paint so that the applied amount is 60 to 80 g per square meter with a brush, and wipe it off with a cotton cloth. (6) Drying. Let stand for more than 16 hours to dry. (7) Third application. Soak the paint into the cotton cloth, rub it like a spiral, and wipe it off with a cotton cloth. (8) Drying. Let stand for more than 16 hours to dry.

  A coating test was conducted on the trial paint 2 and the comparative paint 3. The comparative paint 3 is a solvent-type oil-based paint for indoor wood parts and is marketed as teak oil and is a solvent-type permeable paint containing about 70 to 75% of a solvent. The test results are shown in Table 2.

  The paint performance of the trial paint 2 is inferior to that of the comparative paint 3, and the volatile organic compound (VOC) is significantly smaller than that of the comparative paint 3.

<Example 3>
Assuming a biaxial stirrer, a spatula was attached to the wall surface of a stainless beaker, it was installed on a rotary table, and a uniaxial stirrer was set on the inner surface of the beaker. This was used as a prototype device. Dehydrated castor oil was put into this prototype device, and 1 part by weight of a metal dryer (cobalt, manganese, zirconium) was added to 100 parts by weight of the dehydrated castor oil and stirred until uniform. Next, 12.5 parts by weight of a nonionic surfactant (polyoxyethylene allyl ether) was added to the stirring liquid and stirred. At this stage, stirring was continued for 20 to 30 minutes while maintaining the temperature at 20 to 40 ° C., and it was confirmed that there was an increase in viscosity. Subsequently, 30 parts by weight of ion exchange water was gradually added. Furthermore, 57.5 parts by weight of ion-exchanged water was added to obtain an adjustment liquid having an oil and fat content of 50% by weight. This adjustment liquid is equivalent to what added the metal dryer to the water dispersion liquid which consists of fats and oils, surfactant, and ion-exchange water.

  This adjustment liquid was applied to a glass plate so as to have a thickness of about 0.13 mm, and the drying property was examined. After 24 hours, a slight coating was observed, but a coating film was formed.

  Next, 5 parts by weight of a color paste adjusted so as to be dispersed in water was added to 100 parts by weight of the adjustment liquid, thereby producing a trial paint 3 for an outdoor xylem. The pigments contained in the color paste used were three colors of iron oxide brown, oxide yellow and carbon black, and these three color pastes were mixed at a ratio of 1: 3: 0.5.

  For the three types of paints, the trial paint 3 and the above-mentioned comparative paint 1 and comparative paint 2, apply these two times to the surface of rice cedar (aka Western Red Cedar) so that the coating amount is 150 g per square meter. And exposed to the south side of the outdoors. The comparative paint 2 caused peeling of the coating film in less than one year. The trial paint 3 and the comparative paint 2 did not peel off even after 3 years.

<Example 4>
Ion-exchanged water was added to the adjustment liquid prepared in Example 3 to adjust the fat and oil to 30% by weight, thereby producing a trial paint 4 for indoor wood (for oil finishing). The trial paint 4 was brushed on the surface of the teak material and the plug material, polished with nylon abrasive paper, then the excess liquid was wiped off with a cotton cloth and dried for 24 hours. Next, after lightly polishing with No. 600 polishing paper, the trial paint 4 was included in a cotton cloth, wiped while sliding in a spiral, and dried for 24 hours. As a result, it was possible to obtain a moist finish that was not inferior to that of the aforementioned comparative paint 3 (commercially available solvent-type oil finish paint). The coating performance after drying was also equivalent to that of Comparative Paint 3.

<Example 5>
Using the prototype device used in Example 3, a non-ionic surfactant (polyoxyethylene alkyl) was added to 30 parts by weight of the polymer oil of cinna tung oil while stirring this polymer oil. 2 parts by weight of ether) (surfactant was 6.7 parts by weight based on 100 parts by weight of fat). After stirring for 15 minutes, stirring was continued while dropping 10 parts by weight of ion-exchanged water. Subsequently, 100 ppm (relative to the polymer oil of Sin Tung oil) of a silicone-based antifoaming agent was added, and then 58 parts by weight of ion-exchanged water was added to obtain an adjustment liquid having an oil and fat content of 30% by weight. A metal drier (cobalt, manganese, zirconium), a preservative (benzimidazole compound), and a freeze stabilizer (propylene glycol) were added to this adjustment liquid to obtain a paint base.

  To this paint base, a color paste adjusted to be dispersed in water, an antifungal agent (isothiazoline compound), and an ultraviolet absorber were added to obtain an outdoor wood part paint. This is designated as prototype paint 5. The color paste adjusted to be dispersed in water is a mixture of three colors of iron oxide brown, oxide yellow, and carbon black in a ratio of 1: 3: 0.5, as in Example 3. is there.

  In the same manner as in Example 1, three types of paints, namely, the trial paint 5, the above-described comparative paint 1, and the comparative paint 4 (commercially available solvent-type outdoor xylem paint mainly composed of an oil-modified alkyd resin) An exposure test was conducted. The prototype paint 5 and the two comparative paints showed equivalent weather resistance.

<Example 6>
A color paste adjusted so that a transparent organic pigment is dispersed in water is added to the paint base prepared in Example 5, and further an additive that imparts performance to improve the feeling of touch is added. The paint for indoor xylem used for indoor such as furniture was made. This is designated as trial paint 6.

  The trial paint 6 and the above-described comparative paint 3 were applied to the surface of a piece of wood, and the paint performance was compared. As a result, the two paints obtained equivalent performance.

<Example 7>
A polymer oil of linseed oil was put into a biaxial stirrer, and 3 parts by weight of a nonionic surfactant (mixed 3 types) was added dropwise to 30 parts by weight of the polymer oil of linseed oil while stirring this. (The surfactant is 10 parts by weight based on 100 parts by weight of fats and oils). While stirring this, 67 parts by weight of ion-exchanged water was added in two stages. As a result, an aqueous dispersion having an oil and fat content of 30% by weight was obtained. A metal drier (cobalt, manganese, zirconium), a preservative (benzimidazole compound), and a freeze stabilizer (propylene glycol) were added to the aqueous dispersion to form a paint base. The nonionic surfactant of the three types used in Example 7 is a mixture of polyoxyethylene alkyl ether A, polyoxyethylene alkyl ether B and polyoxyethylene castor oil in a ratio of 40:40:20. is there. The difference between A and B in the polyoxyethylene alkyl ether is the difference in the characteristic values of the cloud point (the temperature at which the aqueous solution of the surfactant turns cloudy) and the HLB (lipophilic and hydrophilic balance). is there.

  This paint base was applied to a glass plate to a thickness of about 0.13 mm, and the dry state after 24 hours was examined. Although there was slight tackiness, a normal coating film with good water repellency could be obtained.

<Example 8>
<Ratio of surfactant to oil and fat>
Using the prototype device used in Example 3, an appropriate range of the ratio of the surfactant to the oil and fat was examined. 3 parts by weight of surfactants per 100 parts by weight of cinna tung oil polymer oil are 1 part, 2 parts, 3 parts, 3.3 parts, 3.5 parts, 4 parts, 5 parts 11 parts by weight, 10 parts by weight, 15 parts by weight, 25 parts by weight, and 50 parts by weight are added, and ion-exchanged water is further added so that the fat and oil content is 30% by weight. The state of the aqueous dispersion was observed. As a result, when the surfactant was 3 parts by weight or less, a normal aqueous dispersion was not obtained, and non-uniform coarse particles were observed, leading to separation of water and fats and oils. When the surfactant was 3.3 to 50 parts by weight, a stable aqueous dispersion was obtained. However, when this aqueous dispersion is made into a paint, if the surfactant exceeds 15 parts by weight, the coating film becomes soft and the intended coating film performance cannot be obtained. In addition, when the amount is 25 parts by weight or more, drying is significantly delayed. Therefore, the ratio of the surfactant to the fat is suitably 3.3 to 15 parts by weight of the surfactant with respect to 100 parts by weight of the fat. Moreover, the mixing ratio and addition amount of an appropriate surfactant vary depending on the type of oil. Furthermore, the ratio of the surfactant for obtaining the target particle size also changes.

<Example 9>
Using the prototype device used in Example 3, 6 parts by weight of a surfactant of 3 types was added to 100 parts by weight of polymerized oil of Chinese paulownia oil, stirred for 15 minutes, and then 50 parts by weight of ion-exchanged water. Part was added gradually. Then, after stirring for 10 minutes, ion-exchange water was added so that the fat and oil concentration would be 10% by weight to obtain an aqueous dispersion. When this aqueous dispersion is made into a paint, since there are few oils and fats as coating film components, it is the lowest oil and fat content level for use as a paint. If the oil and fat content is less than this, it is not suitable as a paint for wood, but it can be used for purposes such as polishing wax and antifouling agent for white wood.

<Example 10>
Carnauba wax previously adjusted to be dispersed in water in the aqueous dispersion of Example 9, similarly adjusted drying accelerator, similarly adjusted silicone-based lubricant, HEC as a thickener (Hydroxyethyl cellulose) or PVC (polyvinyl alcohol) and a viscosity modifier (polyether type, urethane association type, urethane-modified polyether type, modified polyacrylic acid type) used in various emulsions are mixed and liquid An antifouling paint was obtained.

Claims (5)

  From an aqueous dispersion obtained by emulsifying 100 parts by weight of fats and oils made from processing oil (excluding those to which an organic solvent has been added) treated with vegetable oil in water using 3.3 to 15 parts by weight of a surfactant, and an additive Water based paint for wood.   The water-based paint according to claim 1, wherein the additive includes a preservative, a freezing stabilizer, a wetting agent, a fungicide, an insect repellent, and a drying accelerator.   The water-based paint according to claim 1, wherein the additive includes a preservative, a freezing stabilizer, a wetting agent, a drying accelerator, and a surface conditioner.   The water-based paint according to any one of claims 1 to 3, wherein the additive further includes a color paste adjusted to be dispersed in water.   The water-based paint according to any one of claims 1 to 4, wherein the ratio of the fats and oils is 10 to 50% by weight with respect to the total weight of the water-based paint.