JPH0132872B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a surface treatment agent for buildings or building materials, particularly inorganic building materials, and more specifically to an acrylic polymer having a fluoroalkyl group and a silyl group having a hydrolyzable substituent in the side chain. , in surface treatment of inorganic building materials,
The present invention relates to surface treatment agents that provide long-term protection for building materials against deterioration factors based on oil-based and water-based substances, such as dirt, frost damage, weathering, chemical damage, etc. Various treatment agents have been used for the purpose of protecting inorganic building materials. Among them, a group of treatment agents called organic penetrating water absorption inhibitors impart water repellency to buildings without changing the appearance of the building even after treatment, and eliminate various deterioration factors due to water absorption of buildings, such as dirt, dirt, etc. It has the effect of protecting buildings from weathering, freezing damage, etc., and is used as a treatment agent for inorganic building materials. Here, the organic penetrating water absorption inhibitor is mainly a silicone-based compound, which is an organic silane compound and its polymer, and when surface-treated on an inorganic building material, The bonded alkyl group exhibits a water-repellent effect and reduces the water absorption of building materials. Silicone-based water-repellent agents have a strong water-repellent effect, and can make the surface layer of a building hydrophobic by using a very small amount, so there is almost no change in the appearance of the building. Many inorganic building materials are valued for their unique aesthetic appearance, which is why they are used in surface treatments for materials such as silicone-based water repellents, which are essentially clear. In this way, silicone-based penetrating water absorption inhibitors are
Although it can be expected to have a protective effect against various deterioration factors based on the water absorption of buildings due to its excellent water repellent effect, its uses and uses are limited due to the drawbacks described below. The water repellency of silicone-based water repellents is
Due to the alkyl group bonded to the side chain, oil repellency cannot be expected; rather, it is lipophilic. For this reason, infiltration of oily substances cannot be prevented. For example, it is not effective against oil-based stains such as exhaust smoke from automobiles, etc., and cannot prevent moisture mixed with surfactants from entering bathrooms and the like. This is a common weakness not only in silicone-based water-repellent materials but also in materials that prevent water from entering through the water-repellent effect of alkyl groups and are intended to protect building materials. Fluorine compounds have conventionally been used as water- and oil-repellent materials. The present inventors have investigated fluorine-based water- and oil-repellent materials as protective treatment materials for building materials, but have not been able to obtain sufficient effects. It is true that some oil repellency was initially confirmed, and good effects were obtained in the water absorption prevention performance against surfactant-containing water and the contamination resistance test with automobile exhaust gas, but the effect was quickly shown in short-term exposure tests. This resulted in a loss. This is believed to be due to the fact that this type of material is merely physically attached to the building material and easily detaches from the material surface under short-term exposure conditions. In addition, there is a material known as fluorocarbon resin paint that has been recognized for its excellent weather resistance, but this material significantly changes the appearance of the building material and is not suitable for the intended use by the inventors.
A good effect could not be observed at a low coating amount that was not suitable for the field and did not change the appearance. The present inventors have conducted extensive studies on treatment agents that can be applied to the surface of buildings or building materials, particularly inorganic building materials, to protect buildings from deterioration factors caused by oil and moisture over a long period of time without changing their appearance. As a result, the main structural unit is a unit formed by a monomer having a (meth)acryloyl group,
It was discovered that an acrylic polymer having both a specific amount of fluoroalkyl group and a hydrolyzable functional group or a silyl group whose atom is bonded to a silicon atom in the molecule exhibits excellent effects, and the present invention completed. That is, the present invention provides a method in which units formed by monomers having a (meth)acryloyl group account for 30% by weight or more based on the total amount of all monomer units, and which contain hydrolyzable functional groups. or 10 to 50 monomer units having a silyl group whose atom is bonded to a silicon atom
This is a surface treatment agent for buildings or building materials, which is prepared by dissolving an acrylic polymer containing 10 to 70 mol% of monomer units having fluoroalkyl groups in an organic solvent. When an inorganic building material is surface-treated with the surface treatment agent of the present invention, a sufficient effect can be obtained even at an extremely low concentration, so that the appearance of the building material is hardly changed. In addition, silyl groups with hydrolyzable functional groups (hereinafter simply referred to as silyl groups) are used as silanol groups in building materials.

It chemically combines with [Formula] and forms a cross-linked structure with each other, firmly fixing it to the building material. Furthermore, since it is an acrylic polymer with excellent weather resistance, it maintains long-term durability. As a result, inorganic building materials retain their beauty for a long time, and are also resistant to frost damage caused by water containing surfactants in bathrooms and deterioration caused by oil on factory floors. becomes possible to protect. Next, the constituent elements of the present invention will be sequentially explained. The silyl group present in the acrylic polymer in the present invention is represented by the following general formula. Here, n represents 1 to 3. R is an alkyl group and/or an aryl group. A represents a hydrolyzable functional group or atom, specifically one or more selected from alkoxy groups such as methoxy, ethoxy, and propoxy groups, hydroxyl groups, and halogens such as chlorine, bromine, and iodine. In addition, methoxy or ethoxy groups are preferred from the viewpoint of reactivity with the base and storage stability. The fluoroalkyl group is a linear one having 3 to 20 carbon atoms as shown below, and the terminal propyl group is preferably a heptafluoropropyl group or a heptafluoroisopropyl group. Here, n represents 3 to 20. A is H, F, an alkyl group and/or an aryl group. As mentioned above, the acrylic polymer in the present invention contains 30% by weight or more of units formed by a monomer having a (meth)acryloyl group, based on the total amount of all monomer units. Monomers having such a (meth)acryloyl group include (meth)acrylic acid esters represented by the general formula below, as well as other silyl groups and (meth)acryloyl groups, specific examples of which will be described later. and fluoroalkyl (meth)acrylates. In the formula, A is hydrogen or a methyl group, and R is an alkyl group. In addition, the acrylic polymer is a copolymer with the above-mentioned (meth)acryloyl group-containing monomer, and contains either a fluoroalkyl group or a silyl group. It may also have other monomer units that do not have . Typical examples thereof include ethylene, vinyl acetate, vinyl chloride, vinylidene chloride, acrylonitrile, and styrene. The proportion of units formed by a monomer having a (meth)acryloyl group in the acrylic polymer is 30% by weight or more, and if it is less than this,
Poor weather resistance. Next, the introduction of silyl groups and fluoroalkyl groups into acrylic polymers will be described. The following methods can be cited as introduction methods. A method using a substitution reaction of a silyl group and a fluoroalkyl group to an acrylic polymer. A method based on copolymerization of a radical copolymerizable monomer containing these and an acrylic monomer. A method based on copolymerization of these added acrylic monomers. Or a method using a combination of these three. Among these, a method based on copolymerization of an acrylic monomer having a silyl group and an acrylic monomer having a fluoroalkyl group is preferred from the viewpoint of ease of production. A typical example of the monomer having a silyl group in the present invention is a monomer having both a silyl group and a (meth)acryloyl group, that is, a monomer having the general formula A monomer represented by (hereinafter referred to as (meth)acrylate silane) and a general formula having an ethylenically unsaturated group as a polymerizable group Ethylene-based silanes shown in the following can be mentioned. R ₁ is a hydrogen atom or a methyl group, R ₂ and R ₃ are a methyl group, ethyl group, or phenyl group, and n is 1 to
It is an integer of 3. m is 0 or 1, l is m=
In the case of 0, it is an integer from 0 to 2, and in the case of m=1, it is 2.
X is an alkoxy group, an acetoxy group, or a group of the general formula (OC ₂ H ₄ ) _p OR ₄ (R ₄ is a hydrogen atom, a methyl group, or an ethyl group, and n is an integer of 1 to 5). Specifically, γ-(meth)acryloyloxypropyltrimethoxysilane, γ-(meth)acryloyloxypropylmethyldimethoxysilane, γ-(meth)acryloyloxypropyldimethoxysilane, 3-(2-(meth)acryloyloxy ethoxy)propyltrimethoxysilane,
3-(2-(meth)acryloyloxyethoxy)
Propylmethyldimethoxysilane, 3-(2-(meth)acryloyloxyethoxy)propyldimethylmethoxysilane, 5-((meth)acryloyloxy)pentyltrimethoxysilane, 5-((meth)acryloyloxy)pentylmethyldimethoxysilane, 5-((meth)acryloyloxy)
Pentyldimethylmethoxysilane, P-vinylphenyltrimethoxysilane, P-vinylphenylmethyldimethoxysilane, P-vinylphenyldimethylmethoxysilane, γ-(meth)acryloyloxypropyltri(β-methoxyethoxy)
Examples include silane. As a monomer having a fluoroalkyl group,
Fluoroalkyl (meth)acrylates are preferred, and specific examples include fluoroalkyl (meth)acrylates represented by the following formula. R is a hydrogen atom or a methyl group. The polymerization method and catalyst used are carried out in accordance with ordinary solution polymerization, but contamination of water must be avoided. The solid content concentration during polymerization, that is, the polymer concentration, is preferably approximately 20 to 70%, more preferably 30 to 60%. The proportion of monomer units having a silyl group in the acrylic polymer is 10 to 50 mol% based on the total amount of all monomer units constituting the polymer,
Further, the proportion of monomer units having a fluoroalkyl group is 10 to 70 mol% on the same basis as above. A more preferable proportion of monomer units having a silyl group and a more preferable proportion of monomer units having a fluoroalkyl group are 20 to 50 mol% and 20 to 50 mol%, respectively.
It is 40-70 mol%. The surface treatment agent of the present invention is used for surface treatment of building materials by diluting and dissolving the polymer in a solvent soluble therein at an arbitrary ratio. In the surface treatment of building materials, workability (an appropriate amount of treatment that is easy to work with is generally 0.1 for spraying).
~0.5 ( ^{approximately} 0.5 (with drug)/m2), and from the viewpoint of performance and cost, the polymer concentration in the surface treatment agent is preferably 0.05 to 20% by weight. Moreover, when applying to mortar concrete by spraying, 1 to 10% by weight is more preferable, and when treating tiles by dipping, 0.1 to 1% by weight is even more preferable. Usable organic solvents vary depending on the polymer composition, but examples include toluene, xylene, benzene, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, cyclohexanone, methanol, ethanol, isopropyl alcohol, diacetone alcohol, and cellosolve. Solvents include acetate, carbon tetrachloride, trichlorethylene, perchlorethylene, chloroform, tetrahydrofuran, ethyl ether, dimethylformamide, mineral spirits, solvent naphtha, hexane, etc. alone or in combination. Among these, mineral spirits, solvent naphtha, and toluene are preferred in terms of workability, and it is also possible and preferred to use higher acrylic esters such as stearyl acrylate as a monomer in order to improve the solubility in these. . The surface treatment agent of the present invention is applied to the surface of a building by a known method. Examples of the surface treatment method include an air spray method, an airless spray method, a roller coating method, a brush coating method, a dipping method, a curtain roll coater method, and the like. The amount of the surface treatment agent of the present invention to be used is determined by the solid content concentration,
Although it varies depending on the porosity of the building material and the surface treatment method, it is approximately 0.05 to 2.0 Kg/m ² . Building materials to which the surface treatment agent of the present invention can be applied include concrete with voids, mortar, cement materials such as ALC, and cellular cocrete;
Inorganic building materials having silanol groups such as slate, calcium silicate plates, sizing boards, ceramics such as tiles, bricks, and roof tiles, and stone are preferable, and other materials such as wood and plastics are also possible. It also exhibits favorable performance as a top coat for cement-based cosmetic materials such as cementolysin. By applying the surface treatment agent of the present invention to the surface of building materials, it is possible to reduce water absorption, impart detergent resistance and stain resistance, and protect building materials without changing their appearance. be. The surface treatment agent of the present invention can also be used in combination with other architectural paints or penetrating water absorption inhibitors. When mixed with architectural paints, it improves the durability of the coating film and improves the alkoxy Even better performance is often obtained when used in combination with a water absorption inhibitor with excellent permeability such as an alkylsilane. Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples. All parts and percentages in each example are by weight, and the test method is as follows. 1. Changes in appearance after application of treatment agent A predetermined amount of treatment agent was applied to building materials, and after being left indoors for 7 days, differences in appearance from untreated products were visually observed and classified and judged as follows. 〇... No change in appearance △... Appearance is slightly different from untreated ×... Significantly different from untreated 2 Water absorption rate After building materials whose surface has been treated with a specified amount of treatment agent are left at room temperature for 7 days The sample was dried at 105°C until it reached a constant weight, left to cool, and then submerged in water to determine the water absorption rate using the following formula. Water absorption rate (%) = Water absorption amount after 1 day / Dry weight × 100 3. Detergent resistance water absorption rate The test specimen prepared in the same manner as in Section 2 was washed with 5% Mama Lemon (neutral household detergent manufactured by Kao Soap Co., Ltd.). It was immersed in water, and the water absorption rate was determined in the same manner as in Section 2. 4. Stain Resistance A test specimen prepared in the same manner as in Section 2 was exposed to nature outdoors with heavy traffic, and the state of dirt was visually observed after 3 months and 1 year, and was judged as follows. ◎...Very good 〇...Good △...Slightly stained ×...Significantly stained Example 1 As fluoroalkyl acrylate 50 parts of γ-methacryloxypropyltrimethoxysilane as a radically polymerizable silane, 200 parts of methyl ethyl ketone (MEK) as a solvent, and 2 parts of azobisisobutyronitrile (hereinafter abbreviated as AIBN) as a radical polymerization initiator. The mixture was placed in a flask equipped with a stirrer and a thermometer, and reacted in a nitrogen atmosphere at a temperature of 90°C for 4 hours. 700 parts of toluene was added to this to obtain a composition with a solid content of 10%. Apply this to the entire surface of the mortar board (7 x 7 x 2 cm)
A 0.3Kg/ ^m2 brush coating was applied and various performance evaluation tests were conducted. The results are shown in Table 1, and the appearance was almost the same as that of the untreated mortar board, and the other properties were also excellent. Example 2 As fluoroalkyl acrylate 50 parts, 25 parts of γ-methacryloxypropyltrimethoxysilane as a radically polymerizable silane, stearyl methacrylate (hereinafter abbreviated as SMA)
25 parts, 200 parts of MEK as the solvent, and 2 parts of AIBN as the radical polymerization initiator.
Made it react. After the reaction was completed, MEK was removed by vacuum distillation to obtain a slightly yellow, highly viscous oily reaction product. The reaction product was soluble in mineral spirits, toluene, and acetone. Next, the reaction product was dissolved using mineral spirits to obtain a surface treated material with a solid content of 1%. Add to this a ceramic interior tile (manufactured by Fujimi Tile, 10cm)
(corner) was soaked for 1 hour. The amount of treatment after 1 hour immersion treatment was approximately 12 g per tile. A performance evaluation test was conducted using this treated tile. The results are shown in Table 1, and showed excellent water absorption prevention performance against detergent water. Examples 3 to 6 Tests were conducted in the same manner as in Example 1 using the materials shown in Table-1. The results are shown in Table 1, and showed good performance. Comparative Examples 1 to 5 Table 2 shows the surface treated materials, test specimens, and
The coating amount and performance evaluation test results are listed, but the performance was significantly inferior in all cases compared to the treated material of the present invention shown in Table 1.

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Claims (1)

[Claims] 1 Based on the total amount of all monomer units, (meta)
The proportion of units formed by a monomer having an acryloyl group is 30% by weight or more, and the proportion of monomer units having a silyl group whose hydrolyzable functional group or atom is bonded to a silicon atom is 10 to 10% by weight. A surface treatment agent for buildings or building materials obtained by dissolving an acrylic polymer containing 50 mol% and 10 to 70 mol% of monomer units having a fluoroalkyl group in an organic solvent.