JPS6176564A - Coating composition - Google Patents

Abstract

PURPOSE:A coating composition that is obtained by adding specific amounts of mountain wood and roasted mountain wood in specific amounts, respectively, to a coating resin, thus being suitable for use as an anticorrosive coating for cars, building and outdoor constructions, because it prevents the substrates from being corroded and gives coating films with high water resistance, film strength and adhesion. CONSTITUTION:The objective composition is obtained by adding (A) 0.5-30pts. wt. of mountain wood, preferably sepiolite, attapulgite or palygorskite and (B) 0.5-30pts.wt. of roasted mountain wood (preferably a substance resulting from heat-treatment of a powder selected from sepiolite, attapulgite or palygorskite at 400-1,100 deg.C to (C) 100pts.wt. of a resin for coating.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to anticorrosion materials for automobiles, building materials, outdoor structures, etc.

(Prior Art and Problems) Paints for automobiles and parts, chemical equipment, building materials, wall structures, agricultural machinery, electrical appliances, etc. are required not only to look beautiful but also to have anti-corrosion performance.

In recent years, as the need for resource conservation has increased, there has been a desire for coated products that do not deteriorate in performance over a longer period of time due to corrosion protection, etc.

In addition, the environments in which coated products are used are becoming more diverse1, and they are increasingly being used in harsh environments where corrosion is likely to occur, and in this sense, demands for anti-corrosion and rust-proofing performance are becoming even stronger.

For example, cars that drive on roads coated with antifreeze agents (calcium chloride or rock salt) constantly come into contact with salt water and the like. Also,
Painted aluminum panels and balconies of buildings in coastal areas are exposed to wind and rain containing seawater. As described above, painted objects are often placed in harsh environments where they are susceptible to corrosion.

Typical types of corrosion that reduce the performance of painted objects are 1. When there is a scratch on a painted object, the welding strength of the base material in that area begins to decrease, and over time the paint film moves outward from the scratch. There is a phenomenon of peeling. There are also the following types of corrosion: Even if there are no scratches, when the coating film comes into contact with water, Na ions or C1- ions in the water permeate the coating film and reach the substrate, forming an anode portion and a cando portion of the counter electrode on the substrate surface. As a result, a local potential difference is generated, the base material is eluted, and the base material is corroded. Then, the adhesion between the coating film and the base material decreases, and over time, the coating film separates from the base material at that part and lifts up. Water accumulates in the gaps, causing blisters, and eventually the paint film ruptures and an aqueous solution called rust fluid flows out, severely damaging the aesthetics and shortening the lifespan of the painted product.

Many researchers have made efforts to prevent such corrosion, and several techniques have been provided so far. The main ones are described below.

In order to prevent corrosion, methods such as increasing the thickness of the paint film by applying multiple coats of paint have been implemented. However, there were drawbacks such as an increase in the number of painting steps and an increase in the amount of paint used. In addition, in order to prevent corrosion, we focused on improving the adhesion between the base material and the coating film, and published JP-A-50-1391
No. 29, JP-A No. 52-151323, a method of introducing a compound that forms a chelate bond at the interface between the substrate and the coating film, or as disclosed in JP-A-53-113835. In recent years, a method has been implemented in which a compensating agent is interposed at the interface between the base material and the coating film.

However, resins that can be chelated or coupled have selectivity, which has the drawback of restricting the selection of resin materials for coatings.

Additionally, a method of incorporating rust-preventing pigments into paints has been implemented to prevent corrosion. Of these, chromic acid-based pigments such as zinc chromate are by far the most common. When these pigments come into contact with moisture, they elute chromate ions, which passivate metal surfaces through their strong oxidizing action, thereby exerting a corrosion-preventing action. However, compounds containing heavy metals are toxic and lack safety.

(Problems to be solved by the present invention) The present invention solves these problems and provides a non-corrosive and non-toxic product even in environments where corrosion is likely to occur, such as being exposed to wind and rain containing seawater or being placed under high temperature and humidity. It is also an object of the present invention to provide a paint with low pollution properties using no additives.

(Means and effects for solving the problem) The present invention is a paint containing a paint resin as a main component, in which 0.5 to 30th1 part of mountain skin and 0.5 to 30 parts of fired mountain skin per 100 parts by weight of the paint resin.
This is a coating composition characterized in that it contains 5 to 30 parts by weight.

Mountain bark is commonly known as mountain cork.
ork), Mountain Leather (Mountain 1
ether), Mountain Wood (Mountain
It is also called wood), etc., and has hydrated magnesium silicate as its main component. Note that a part of magnesium may be replaced with aluminum, iron, etc.

Specifically, sepiolite,
Examples include attapulgite, palygorskite, and meerschaum.

The substance is an aggregate of long fibers having a quadrilateral cross section with sides of 0.01 to 0' and 1 uLm, and the aggregate has a large number of holes in the length direction of the fibers. In addition, the fiber has highly reactive hydroxyl groups on its surface, and the substance is
It itself has the property of absorbing and adsorbing a large amount of water.

Burnt mountain bark is obtained by heat-treating (calcining) this mountain bark powder at a temperature of 400 to 1100°C.The processing time is required to be at least 15 minutes, and the longer the time, the more stable the performance of the fired mountain bark will be. be able to. The particle size of the fired product is 100-0.1p
m is desirable.

Structural changes due to heat treatment are not necessarily clear, but compared to the unfired mountain skin, the calcined mountain skin remains fibrous, but zeolite water, bound water, and structural water contained in the crystal structure What is said to be has been transformed into a smaller structure. Therefore, it is thought that it has the property of incorporating a larger amount of Na. Therefore, while seki has a certain effect, fired sanpi has a greater effect in inhibiting corrosion.

In this way, when the prepared calcined mountain skin (powder) is blended into paint, it can capture ions in salt water into the paint film, effectively suppressing the occurrence of corrosion such as blistering. be.

The amounts of mountain skin and calcined mountain skin contained in the coating composition according to the present invention are 100 parts by weight of paint resin, 1. , l, is in the range of 0.5 to 30 parts by weight, and the total amount of both is preferably in the range from 1 to 30 parts by weight. In particular, it is preferable to set the mountain bark to 0.5 to 20 heavy weights, and the mature mountain bark to 0.5 to 11 heavy weights, since the effect of the mountain bark and fired mountain bark will be the highest.

The blended solution of Yamapi exhibits some corrosion resistance and excellent water resistance at 0.5 parts by weight or more, and prevents the peeling of the paint film, but 3
When 0 ton exceeds 100 ton, the resulting paint film becomes less flexible and brittle.

On the other hand, when the amount of calcined mountain skin is 0.5 parts by weight or more, it exhibits anti-corrosion effects, especially anti-corrosion and anti-rust effects against salt water, but when the amount exceeds 30 parts by weight, the stability of the paint deteriorates. This will adversely affect the aesthetic appearance, such as the lack of gloss in the paint film.

In the same sense, it is not preferable for the total amount of mountain skin and fired mountain skin to exceed 30 parts by weight, but it is permissible depending on the purpose and conditions of use.

The anticorrosive paint according to the present invention is preferably in a state in which mountain bark and calcined mountain bark powder are appropriately dispersed and solidified in the coating resin. It may be one that is made easy to paint by adding a solvent to give it a suitable viscosity. Furthermore, suitable amounts of pigments, resin preservatives, antifoaming agents, leveling agents, hardening accelerators, and plasticizers for coloring the paint may be added.

Although the phenomenon by which the anticorrosive paint of the present invention exhibits the effect of preventing corrosion such as rust on the base material, which causes peeling of the paint film such as blistering when it is formed as a paint film on the surface of a painted product, is not clear. It can be considered as follows.

Even if corrosive ions, such as Na
This is thought to be because a does not reach the base material. If there is a scratch on the paint film, this hot water part becomes the 7 note of a corrosion battery, and the area under the paint film around the hot water part becomes a cathode. In this case, if Na is present at the cathode, OH- generated at the cathode is successively neutralized by Na, and corrosion of the base material progresses. It is thought that the presence of the fired mountain bark here causes Na+ to be incorporated into the fired mountain bark, suppressing the occurrence of corrosion and rust. It's not a mountain bark. However, mountain bark has a strong effect of improving water resistance, so when used in combination with fired mountain bark, an excellent paint can be obtained.

The coating resin of the present invention is used in paints used in conventional painting, and is easily formed into a film, and is also a material that mixes well with mountain bark and fired mountain bark and can be dispersed appropriately. Good to have.

Specific examples include thermosetting resins such as alkyd resins, aminoalkyd resins, melamine resins, acrylic resins, urethane resins, epoxy resins, urea resins, and phenol resins, thermal radiation and viscous resins such as nylon resins, and vinyl chloride. ,
Latex resins such as styrene-butadiene resin and nitrile-butadiene resin, water-based resins such as alkyd resins, epoxy resins, and alkyd-modified melamine resins, oil-based resins such as linseed oil, and even nitrocellulose.

The method for preparing the anticorrosive paint of the present invention is as follows. First, a commonly used organic paint is prepared. The organic paint preferably contains, in addition to the paint resin, pigments, additives, and a solvent to achieve a viscosity suitable for painting work.

On the other hand, a predetermined amount of powdered mountain bark and fired mountain bark are prepared and mixed with the organic paint. At this time, mixing methods include ball mills, sand grinders, roll mills, etc. It is necessary to mix the calcined mountain bark into the organic paint until it is sufficiently dispersed. By this mixing, it is preferable that the mountain bark be made into a fiber state under the condition of contact with the resin.
．． It has a size of about 1 to several meters, and is uniformly dispersed in an amorphous three-dimensional direction in the resin. It is also possible to prepare a paint resin, add mountain bark or fired mountain bark as described above, reduce the amount to 1%, and then add pigments, etc.

Mountain bark is usually made by pulverizing materials extracted from mines using a conventional method such as a crusher, but normal pulverization results in particles of 0.5 to 200 pm. The heat-treated calcined mountain bark of the present invention differs from general mountain bark particles in that it exhibits a finer, loosened fiber shape with a high slenderness ratio.

The dispersion state of mountain bark and fired mountain bark is related to the corrosion resistance of coating, l
1117, it is important to uniformly disperse fibrous mountain bark and fired mountain bark to avoid agglomeration.

In order to make the dispersion of mountain bark and fired mountain bark more uniform,
It is advisable to further add a solvent in an amount of 5 to 10 times the total weight of the mountain skin and fired mountain skin.

The paint obtained in this way is applied to a base material such as an iron plate by brushing, spraying with a spray can, etc., and then dried to form a coating film on the surface of the base material. .

Even if the coating film is exposed to salt water for a long period of time, the salt and cations in the water do not easily reach the base material, so it is less likely to blister due to corrosion such as rust (corrosion resistance). Furthermore, the coating film has a fibrous skin that does not easily allow moisture to pass through the coating film even when exposed to hot water at about 40°C for a long period of time.
Because it is reinforced with fired mountain skin, the paint film is less likely to peel or crack (#water-based).

(Example) Example 1 8 parts by weight of carbon black, 5 parts by weight of zinc white, 3 parts by weight of calcium carbonate, and 70 parts by weight of butyl cellosolve were placed in a sand grinder container for 100 parts by weight of aqueous epoxy-modified alkyd resin of a heavy plate. Quantitative 2 preparations, 2500rp
The mixture was dispersed for 2 hours at m. A predetermined weight part in the range of 0 to 15 parts by weight of calcined mountain bark obtained by firing at a predetermined temperature for 2 hours in a temperature range of 200 to 1200 ° C. with a grain size of 60 to 100 mesh, A mixture of 0 to 15 parts by weight of the mountain skin that passed through a 100-mesh sieve and 130 parts by weight of butyl cellocel was added, and the mixture was mixed again with a sand grinder at 2500 rpm.
The water-based paint of the present invention was prepared by dispersing the mixture at m for 3 hours.

The composition of this water-based paint is shown in Table 1.

Furthermore, in order to adjust each paint to a viscosity suitable for spray gun painting, five sheets of 5PCC soft river boards (70 x 150 x 0 ．．
Each paint was applied to a dry coating film (8 tmm) to a thickness of approximately 20 ALm. After painting, these soft hard boards were baked at 110°C for 20 minutes to form a paint film.

Cuts were made in the paint film of three of these five sets of coated mild steel plates until they reached the base material using a cutter knife, and a corrosion prevention test was conducted using the salt spray test method in accordance with JIS 1-5400. . The other two sheets were subjected to a wood resistance inspection test using a water resistance test method.

In addition, the evaluation of E4 corrosion resistance is based on the width of the bulge from the cut hot water part to 6 m.
On the other hand, watertightness 74 was evaluated by the time until peeling occurred (referred to as #water time) by a 1 mm pitch goggle test.

The results are shown in Table 2.

Regarding the O and X marks in the table, the O mark indicates that water resistance and corrosion resistance were improved, while the X mark indicates that no improvement in water resistance and corrosion resistance was observed. In addition, water resistance is based on the water resistance time (96 hours) of a paint film that does not contain any mountain skin or fired mountain skin, while corrosion resistance is shown for each mountain skin content in paints containing mountain skin. The SS time was used as the standard. Further, the SS time of the coating film that did not contain mountain skin or fired mountain skin was 80 hours.

Table 1 Table 2 Example 2 Rutile titanium oxide: 40 Higashi Oribe, calcium carbonate: 70 Tamako, zinc white: 2 to 100 parts by weight of water-dilutable linseed oil
0 parts by weight, cobalt naphthenate/Izt (cobalt content 6
%) 2.2 parts by weight, and 0 to 28 parts by weight of calcined mountain bark powder having the same particle size as Example 1 and calcined at a predetermined temperature in the temperature range of 1200°C. A predetermined amount of the mountain bark that has passed through a sieve of 1 part of the specified type ti and 100 menshu, in the range of 0 to 28 parts, is charged into a Sandgra ink container and heated to 2500 ml.
An uninvented coating material containing linseed oil resin as a main component was prepared by dispersing 41 Terama in pm. The composition at this time is shown in Table 3.

Next, each of the above paints was applied using a percoater to five spccem boards (7 x 150 x 0.8 mm), which had been previously degreased with petroleum benzine, to a dry film thickness of about 35 mm. The coated mild steel plate was held at 120° C. for 20 minutes to form a dry coating.

Make a cut in the coating film of each of these 5 pieces of 11 old L1 seedlings with a canter knife, reaching the base material.
A corrosion resistance test was conducted using the salt water jet A test method in accordance with IS.5400, and the remaining two sheets were subjected to a water resistance adhesion test using the water resistance test method.

These tests and evaluation methods are the same as in Example 1. The results are shown in Table 4.

In addition, the water resistance time of the fired mountain skin and the paint film that does not contain the mountain skin is 7
2 hours, SS time was 48 hours.

Table 3 Table 4 Example 3 Mountain skin powder with a particle size of 300 mesh passes per 100 parts by weight of commercially available thermosetting acrylic paint resin (manufactured by Mitsui Toatsu Chemical Co., Ltd., trade name: Flumatex, 7A2-5) 40
1 at a given temperature in the temperature range from 0℃ to 1200℃
A predetermined weight part in the range of 15 parts by weight from the burned mountain bark O obtained by firing for a time and 1 part by weight of the mountain bark powder passed through 300 menshu.
To a predetermined weight part in the range of 5 parts by weight, a thinner whose main component is xylene in an amount of 5 to 10 times the combined amount of calcined mountain bark powder and mountain bark powder is added and dispersed in an emulsifying machine to form the above-mentioned acrylic paint resin. The acrylic paint of the present invention was prepared by mixing and dispersing 100 g of T and 30 parts by weight of rutile titanium oxide in a ball mill for 24 hours.

The blending composition at this time is shown in Table 5.

Table 5 The above paint was further diluted with thinner and adjusted to a viscosity suitable for painting with a spray gun, and then a 5PCC mild steel plate (7 x 150 x 0.8 t
For each test number, five coats of the above paint were applied so that the dry film thickness was approximately 30 mm). After coating, these mild steel plates were baked at 160° C. 12 O for minutes to form a coating film.

Next, the coating film on the surface of three mild steel plates among these five coated plates was used for one corrosion resistance test, and the other two were subjected to a water resistance test, and the test was conducted in the same manner as in Example 1. Each test was conducted and evaluated.

The results are shown in Table 6.

In addition, the water resistance time of the paint film not containing the mountain skin and the fired mountain skin was 240 hours, and the SS time was 190 hours.

Table 6 Example 4 80 parts by weight of nitrocellulose (manufactured by Ohira Chemical Products Co., Ltd.), 20 parts by weight of non-oxidized alkyd resin (Betsukosol 1308, manufactured by Dainippon Ink Chemicals Co., Ltd.), and 10 parts by weight of rutile titanium oxide. 250 parts by weight of MIBK, 300 mesh pass of mountain bark powder was fired at a predetermined temperature in the temperature range of 200°C to 1200'C for 2 hours. Part, 30
Pour a predetermined amount of mountain bark powder of 0 mesh pass into a sand grinder container in a range of 0 to 35 constrictions.250
The coating composition of the present invention was obtained by dispersing at 0 rpm for 4 hours.

Table 7 shows the blending composition of the mountain skin and the fired mountain skin at this time. Next, each of the above paints was applied using a bar coater to five sheets of SPCC soft wood boards (7 x 150 x 0.8'mm), which had been degreased in advance with petroleum benzene, to a dry film thickness of about 35 luros. The painted mild steel plate was held at 120° C. for 20 minutes, and a coating film consisting of a paint containing nitrocellulose as the component was formed on the surface of the mild steel plate in the same manner as above.

The paint film on the surface of three of these five types of painted boards was cut with a cutter knife to reach the base material, and the two were used for the corrosion resistance test, and the other two were tested for water resistance. Tested. The test method and evaluation method are the same as in Example 1.

The results are shown in Table 8.

In addition, the water resistance time of the paint film not containing the mountain skin and the fired mountain skin was 32 hours, and the SS time was 24 hours.

Table 7 Table 8 Example 5 After adding and dissolving 65 parts by weight of isopropyl alcohol to 100 parts by weight of alkynd resin, 1 part by weight of 0 to 25 parts by weight of the same calcined mountain bark used in Example 3 was added. Add mountain bark within the range of 0 to 20 parts by weight, and atomize and disperse using a sand grinder and a ball mill until the particle size of the burned mountain bark and mountain bark becomes 0.5 pm or less. Thereafter, 10 parts by weight of calcium carbonate, which is a white pigment, was further added, and the mixture was again mixed and ground using a sand grinder until the particle size of calcium carbonate became 3 pLm or less.

Table 9 shows the mixing ratio of calcined mountain skin and mountain skin to Alkynd resin.

Table 9: Alkynes containing calcined mountain bark and white pigment
- Add distilled ion exchange water to the resin, solid content ♀ - Calcium
The emulsion was adjusted to 5 qr% by weight, and an emulsion was formed using a high-speed stirrer to obtain an anodic deposition type electrodeposition paint.

In addition, in order to prevent gelation of the resin during the addition of distilled ion-exchanged water, the pH was adjusted while maintaining it at 8 using i-ethylamine. In addition, an antifoaming agent was also added at the same time to avoid the inclusion of air bubbles during A adjustment.

For each of the anodic deposition type electrocoating paints prepared as above, a 5PCC mild steel plate (70 x 150
Electrodeposition coating was performed under the conditions shown in the table, and five coated plates with a coating film thickness of about 25 lm were prepared for each experiment number.

: FSI 0 Table Next, use a cutter knife to make cuts that reach the base material on the paint film on the surface of three of the five coated plates.
A corrosion resistance test was conducted using a salt spray test method in accordance with JIS 5400, and the remaining two sheets were tested for water resistance adhesion using a water resistance test method.

These test and evaluation methods are the same as in Example 1.

The results are shown in Table 11.

In addition, the water resistance time of the coating film not containing the mountain skin and the fired mountain skin was 140 hours, and the SS time was 120 hours.

Table 11 (Effects of the Invention) As mentioned above, since the coating film obtained by the present invention contains the fibrous calcined skin and the Fa fibrous skin, it prevents corrosion such as rust caused by salt and has a U & male shape. Water resistant due to mountain bark
Since it imparts film strength, it has the property of good adhesion.

Claims (3)

[Claims] (1) A coating composition characterized by containing 30 parts by weight of 0.5 to 30 parts by weight and 30 parts by weight of 0.5 to 0.5 to 100 parts by weight of a paint resin. (2) The coating composition according to claim 1, wherein the mountain skin is a powder of sepiolite, attapulgite, palygorskite, or the like. (3) The fired mountain skin is made of mountain skin powder such as sepiolite, attapulgite, palygorskite, etc. from 400 to 1100.
3. The coating composition according to claim 1, wherein the coating composition is a material that has been heat-treated in the temperature range of .degree.