KR102707245B1 - Water-based inorganic paint composition having adsorption functions - Google Patents

Abstract

The non-combustible and adsorption functional water-based inorganic paint composition according to the present invention is characterized by comprising a silica aerogel whose surface is modified with a binder including lithium silicate and a silane compound having an anhydride group at a terminal.

Description

{Water-based inorganic paint composition having adsorption functions}

The present invention relates to an aqueous inorganic paint composition having excellent flame retardancy and adsorption performance.

Buildings used as residential or office spaces have developed in various ways to protect people from rain and snow and from external environmental changes such as heat and cold.

In addition to the cement concrete that forms the skeleton of a building, various materials such as wood, tiles, MDF, and plaster are used for interior decoration on the inner walls and floors of the building. These architectural decoration materials can be bonded with adhesives, and most of these adhesives contain volatile organic compounds (VOCs). In particular, MDF is a board processed by mixing wood fibers and adhesives, and contains a large amount of adhesives. Adhesives release volatile organic compounds such as formaldehyde, toluene, and xylene over time, and the released volatile organic compounds are substances that cause sick house syndrome and have various negative effects on the skin and respiratory system of the human body. Accordingly, the development of architectural decoration materials that do not contain volatile organic compounds is actively being conducted, and in addition, various paints that can absorb and remove volatile organic compounds released from adhesives are being developed.

Meanwhile, as property and human damage caused by fires have become a problem recently, the demand for building interior materials that exhibit fire-retardant performance is increasing. Accordingly, there is a need to develop a paint composition with excellent fire-retardant performance that can be applied as building interior materials to absorb harmful substances or safely protect people and property from fire.

Republic of Korea Patent Publication No. 10-2018-0098813

An object of the present invention is to provide a coating composition having excellent fire resistance even at a thin film thickness.

Another object of the present invention is to provide a paint composition having excellent adsorption performance for volatile organic compounds such as formaldehyde and adsorbing harmful substances present indoors.

The non-combustible and adsorption functional water-based inorganic paint composition according to the present invention is characterized by comprising a silica aerogel whose surface is modified with a binder including lithium silicate and a silane compound having an anhydride group at a terminal.

The non-flammable and adsorbent functional water-based inorganic paint composition according to the present invention may be characterized by including diatomaceous earth, titanium dioxide, zeolite and silica gel, the surface of which is modified with a silane compound containing an anhydride group at a terminal.

The non-combustible and adsorption functional water-based inorganic paint composition according to the present invention may be characterized by further comprising illite and bentonite.

In a non-combustible and adsorption functional water-based inorganic paint composition according to one embodiment of the present invention, the binder may be characterized by including a redispersible powder resin.

In a non-flammable and adsorbent functional water-based inorganic paint composition according to one embodiment of the present invention, the re-emulsifiable powder resin may be characterized by including a polyvinyl alcohol emulsifier on the surface of acrylic particles.

In a non-combustible and adsorption functional water-based inorganic paint composition according to one embodiment of the present invention, the re-emulsifiable powder resin may be characterized by having an average particle diameter of 0.02 to 0.5 ㎛.

In a non-combustible and adsorbent functional water-based inorganic paint composition according to one embodiment of the present invention, the silica aerogel powder may be characterized by having an average particle diameter of 50 ㎛ or less.

In a non-flammable and adsorbent functional water-based inorganic paint composition according to one embodiment of the present invention, the silane compound including an anhydride group at the terminal may be characterized by satisfying the following chemical formula 1.

[Chemical Formula 1]

In the above chemical formula 1,

L is a direct bond or a straight or branched chain alkylene group having 1 to 10 carbon atoms,

R ₁ to R ₃ are each a straight-chain or branched-chain alkyl group having 1 to 3 carbon atoms.

In a non-combustible and absorbent functional water-based inorganic paint composition according to one embodiment of the present invention, the diatomaceous earth may be characterized in that impurities are removed by calcination.

The adsorption functional inorganic paint composition according to the present invention is characterized by including a silica aerogel whose surface is modified with a binder including lithium silicate and a silane compound having an anhydride group at a terminal, and thus has the advantages of high moisture absorption/desorption capacity and high volatile organic compound adsorption rate such as formaldehyde and excellent nonflammability.

The advantages and features of the embodiments of the present invention, and the methods for achieving them, will become clear with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and the present embodiments are provided only to make the disclosure of the present invention complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

In describing embodiments of the present invention, if it is judged that a detailed description of a known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. In addition, the terms described below are terms defined in consideration of functions in the embodiments of the present invention, and these may vary depending on the intention or custom of the user or operator. Therefore, the definitions should be made based on the contents throughout this specification.

The non-combustible and adsorption functional water-based inorganic paint composition according to the present invention is characterized by comprising a silica aerogel whose surface is modified with a binder including lithium silicate and a silane compound having an anhydride group at a terminal.

The non-flammable and adsorption functional water-based inorganic paint composition according to the present invention can be applied as an interior material inside a building to absorb or release moisture in indoor air to help control humidity, can improve indoor air quality by adsorbing and removing volatile organic compounds such as formaldehyde, and has the advantage of preventing fire occurrence due to its excellent non-flammable performance.

A non-flammable and adsorbent functional water-based inorganic paint composition according to one embodiment of the present invention may include diatomaceous earth, titanium dioxide, zeolite, and silica gel, the surface of which is modified with a silane compound having an anhydride group at a terminal, and through such modification, dispersibility can be secured and the workability of the paint and the durability of the coating film can be secured.

In addition, the non-flammable and adsorption functional water-based inorganic paint composition according to one embodiment of the present invention may further include illite and bentonite, and by including these, the surface hardness of the paint film after curing can be improved.

Lithium silicate can be prepared by using a lithium silicate aqueous solution mixed with water, and can be mixed with a re-emulsifiable powder resin, a surfactant, and water in an aqueous solution state to form a first agent. At this time, the aqueous solution containing lithium silicate can contain 10 to 40 wt% of lithium silicate, preferably 15 to 30 wt%, and more preferably 17 to 25 wt%. In addition, the lithium silicate can be used having a molar ratio of Li ₂ O : SiO ₂ of 1:3 to 7, preferably 1:4 to 6, and by satisfying this range, the mechanical strength and surface hardness of the coating film after curing can be increased.

In a non-flammable and absorbent functional water-based inorganic paint composition according to one embodiment of the present invention, the binder may further include a redispersible powder resin. The redispersible powder resin means an emulsifier layer formed on the surface of polymer particles to easily disperse the polymer particles and emulsify them. For convenience of explanation, the polymer particles are hereinafter referred to as a core. The core may preferably use an acrylic or ethylene vinyl acetate polymer, and the emulsifier layer may use polyvinyl alcohol. In addition, the redispersible powder resin may have an average particle diameter of 0.02 to 0.5 ㎛, preferably 0.05 to 0.3 ㎛, and by using a redispersible powder resin satisfying such a particle diameter range, adhesion to the construction surface can be secured and storage stability can be improved.

In addition, the binder may include 30 to 50 parts by weight, preferably 32 to 45 parts by weight, of a redispersible powder resin relative to 100 parts by weight of the lithium silicate aqueous solution, and by satisfying this range, it is possible to prevent a decrease in adhesion and a decrease in storage stability and to form a coating film with excellent adsorption capacity.

The above binder can secure storage stability by including a surfactant, and can maintain uniform mixing even when mixed with a second agent thereafter. Specifically, a nonionic surfactant can be used as the surfactant, and by using a nonionic surfactant, high dispersibility can be secured while minimizing the influence on other compositions of the paint composition. More specifically, a polyoxyethylene-based surfactant can be used as the surfactant. At this time, the binder can contain 0.5 to 5 parts by weight, preferably 1 to 3 parts by weight, of the surfactant relative to 100 parts by weight of the lithium silicate aqueous solution, and by satisfying this range, the effect of improving dispersibility can be exhibited, while preventing deterioration of physical properties due to mixing of a large amount of surfactant.

Such binder may be included in an amount of 25 to 45 parts by weight, preferably 29 to 40 parts by weight, per 100 parts by weight of diatomaceous earth, and by satisfying this range, a constant surface hardness can be secured while exhibiting high adsorption performance.

In a non-combustible and adsorbent functional water-based inorganic paint composition according to one embodiment of the present invention, diatomaceous earth, titanium dioxide, zeolite, and silica gel may be characterized in that they are surface-modified with a silane compound having an anhydride group at a terminal. This terminal anhydride group undergoes a ring-opening reaction during the modification process, and has the advantage of making the surfaces of diatomaceous earth, titanium dioxide, zeolite, and silica gel hydrophilic, thereby significantly improving dispersibility and dispersion stability.

Specifically, a silane compound containing an anhydride group at the terminal can satisfy the following chemical formula 1.

[Chemical Formula 1]

In the above chemical formula 1, L is a direct bond or a straight or branched chain alkylene group having 1 to 10 carbon atoms, preferably a straight or branched chain alkylene group having 1 to 5 carbon atoms,

R ₁ to R ₃ are each a straight-chain or branched-chain alkyl group having 1 to 3 carbon atoms, preferably a methyl group or an ethyl group.

The above silane compound may be included in an amount of 1 to 5 parts by weight, preferably 1.2 to 3.5 parts by weight, relative to 100 parts by weight of the diatomaceous earth, and within this range, there is an advantage in that it can improve the hydrophilicity of particulate matter such as diatomaceous earth while preventing deterioration of the durability of the entire paint.

The above diatomaceous earth can be used after removing impurities or organic substances blocking the pores through calcination. Preferably, the diatomaceous earth can be calcined at 800 to 1200°C after adding a flux, etc., and by using such calcined diatomaceous earth, the indoor air quality can be improved by adsorbing harmful substances with high porosity.

The above diatomaceous earth may be used having an average particle size of 2 to 60 ㎛, preferably 10 to 58 ㎛, and more preferably 20 to 45 ㎛, and a whiteness of 90% or more. By satisfying these average particle size and whiteness, it has the advantage of enhancing the aesthetics when applying paint and enabling the formation of a uniform coating film with high dispersibility.

The non-flammable and absorbent functional water-based inorganic paint composition according to one embodiment of the present invention has the advantage of showing high hiding power by including titanium dioxide. At this time, the titanium dioxide may be used having an average particle diameter of 0.1 to 2 ㎛, and preferably 0.2 to 1 ㎛. In addition, the titanium dioxide may be included in an amount of 20 to 50 parts by weight, and preferably 25 to 40 parts by weight based on 100 parts by weight of the diatomaceous earth. In this range, the composition shows high hiding power and can prevent reduction in convenience of construction.

The non-flammable and adsorption functional water-based inorganic paint composition according to the present invention can improve indoor air quality by including zeolite and having high hygroscopicity and adsorbing formaldehyde and the like. Specifically, the zeolite can be used having an average particle diameter of 3 to 5 ㎛, preferably 3.2 to 4.5 ㎛, and a SiO ₂ /Al ₂ O ₃ ratio of 2 to 2.8, and has the advantage of exhibiting high compatibility and formaldehyde adsorption performance by satisfying such ranges. The zeolite is included in an amount of 40 to 60 parts by weight, preferably 42 to 57 parts by weight relative to 100 parts by weight of diatomaceous earth, thereby securing surface hardness and durability while exhibiting an excellent indoor air quality improvement effect.

The non-flammable and adsorption functional water-based inorganic paint composition according to the present invention can exhibit excellent hygroscopicity and moisture resistance by including silica gel. The silica gel can be A-type or B-type silica gel, and preferably B-type silica gel. The silica gel can secure compatibility by using one having an average particle diameter of 5 to 35 ㎛, and preferably 10 to 25 ㎛. The silica gel is included in an amount of 40 to 80 parts by weight, and preferably 50 to 65 parts by weight relative to 100 parts by weight of the diatomaceous earth, to secure a high adsorption rate and excellent durability.

The non-flammable and adsorption functional water-based inorganic paint composition according to the present invention can exhibit excellent non-flammability by including silica aerogel powder. Specifically, the silica aerogel powder can satisfy an average particle size of 50 ㎛ or less, specifically 10 to 40 ㎛, and can secure excellent modification effect and dispersibility within this range. More specifically, the silica aerogel can secure high non-flammability by using an average pore diameter of 10 to 40 nm, a specific surface area of 450 to 600 m2/g, and a porosity of 90% or more.

Silica aerogel powder can be added in an amount of 3 to 7 parts by weight, preferably 3.5 to 6.5 parts by weight, per 100 parts by weight of diatomaceous earth. If a small amount of silica aerogel powder is added, it is difficult to secure non-flammability, and if a large amount of silica aerogel powder is added, it may be difficult to secure durability of the entire coating film.

The non-flammable and adsorption functional water-based inorganic paint composition according to one embodiment of the present invention may further include one or more selected from bentonite, illite, calcium hydroxide, etc., and preferably includes illite and bentonite to assist moisture absorption and desorption functions of the paint film and formaldehyde adsorption, etc. Illite may be used having an average particle size of 0.5 to 5 ㎛, and bentonite may be used having an average particle size of 5 to 20 ㎛, and illite and bentonite may be included in an amount of 10 to 25 parts by weight, respectively, relative to 100 parts by weight of diatomaceous earth.

The absorption functional inorganic paint composition according to one embodiment of the present invention may further contain water. At this time, the water may be added in an amount of 130 to 200 parts by weight, preferably 140 to 180 parts by weight, based on 100 parts by weight of diatomaceous earth. By satisfying this range, the paint can be conveniently applied and have a thickness of a certain level or more, thereby having the advantage of exhibiting excellent moisture absorption/desorption and absorption functionality after the film is manufactured.

Hereinafter, the present invention will be specifically described by examples and comparative examples. The examples below are only intended to help understanding the present invention, and the scope of the present invention is not limited by the examples below.

[Manufacturing Example 1]

100 g of diatomaceous earth having an average particle size of 45 ㎛ and a whiteness of 95% or higher, 33 g of titanium dioxide (TiO ₂ ) having an average particle size of 0.4 ㎛, 50 g of zeolite (zeolite 13 X) having an average particle size of 4 ㎛ and a SiO ₂ /Al ₂ O ₃ ratio of 2.3, 57 g of B-type silica gel having an average particle size of 15 ㎛, and 5 g of silica aerogel powder having an average particle size of about 25 ㎛ are added and mixed to 150 g of water. To this, 3 g of (3-triethoxysilyl)propylsuccinic anhydride as a modifier is added, and the mixture is further stirred at room temperature for 2 hours. After that, 15 g of illite having an average particle size of 1.5 ㎛ and 15 g of bentonite having an average particle size of 10 ㎛ are further added and mixed. Here, 33 g of a binder solution was added to finally manufacture an absorption functional paint. At this time, the binder solution was a lithium silicate aqueous solution (A) having a molar ratio of Li ₂ O : SiO ₂ of 1:5 and a solid content of 20 wt%, a redispersible powder resin (B) emulsified with a polyvinyl alcohol emulsifier having an average particle diameter of 0.1 ㎛ and a degree of polymerization of about 500 in an acrylic powder resin, and a polyoxyethylene surfactant (C), and A : B : C was mixed in a weight ratio of 100 : 40 : 2.

[Manufacturing examples 2 to 6]

The paint composition was manufactured in the same manner as in Manufacturing Example 1, but the amount of the paint composition added was varied as shown in Table 1 below to manufacture the paint composition. However, in Table 1, some of the compositions of the second agent were omitted, and the omitted compositions were added in the same ratio as in Manufacturing Example 1.

Manufacturing example Diatomaceous earth TiO ₂ 13X Silica gel Aerogel Illite Bentonite Modifier 1 100 33 50 57 5 15 15 2 2 100 35 50 55 5.5 14 17 2 3 100 33 50 57 5 15 15 0.5 4 100 33 50 57 5 15 15 0 5 100 33 30 57 5 15 15 2 6 100 33 50 57 1.5 15 15 2

Confirmation of the physical properties of manufactured adsorption paint

The moisture absorption and moisture release of the coating film formed with the adsorption paint manufactured according to KS F 2611 were measured and shown in Table 2. At this time, the test piece was repeatedly coated with the paint twice and the average thickness after curing was unified to 0.5 mm, and then subsequent experiments were performed.

According to KS F ISO 1182, the mass reduction rate and the temperature difference between the maximum temperature and the final equilibrium temperature (hereinafter referred to as the temperature difference) were measured, and the results are shown in Table 2. At this time, in order to satisfy non-combustibility, the mass reduction rate must be 30% or less, and the temperature difference must be 20℃ or less.

Manufacturing example Moisture absorption
(g/㎡) Formaldehyde
Accumulated adsorption amount (㎍/㎡) Non-flammability test Mass reduction rate (%) Temperature difference (℃) 1 70 7,400 1.5 2.8 2 72 7,500 1.6 2.6 3 68 7,100 1.7 3.5 4 60 6,900 1.9 3.8 5 68 6,600 1.8 3.1 6 62 7,000 1.8 6.4

Referring to Table 2, it can be confirmed that the paints of Manufacturing Examples 1 to 6 all passed the nonflammability standard. However, in the case of Manufacturing Example 6 containing a small amount of silica aerogel, the temperature difference between the maximum temperature and the final equilibrium temperature was relatively large, and through this, it can be confirmed that the nonflammability is low compared to the other Manufacturing Examples. In addition, it can be confirmed that when a small amount of silane modifier was added or when it was not added, low moisture absorption/desorption amounts and formaldehyde adsorption amounts were shown, and this can be seen to indicate that the moisture absorption/desorption and adsorption effects can be improved by improving dispersibility.

Claims (9)

A silica aerogel, diatomaceous earth, titanium dioxide, zeolite and silica gel, the surface of which is modified with a binder including lithium silicate and a silane compound of the following chemical formula 1 having an anhydride group at the terminal,
A non-flammable and adsorption functional water-based inorganic paint composition characterized in that the binder comprises a redispersible powder resin containing a polyvinyl alcohol emulsifier on the particle surface.
[Chemical Formula 1]

(In the above chemical formula 1,
L is a direct bond or a straight or branched chain alkylene group having 1 to 10 carbon atoms,
R1 to R3 are each a straight-chain or branched-chain alkyl group having 1 to 3 carbon atoms.)
delete In paragraph 1,
A non-flammable and adsorption functional water-based inorganic paint composition characterized in that the paint composition further comprises illite and bentonite.
delete delete In paragraph 1,
A non-flammable and adsorption functional water-based inorganic paint composition, characterized in that the above-mentioned re-emulsifiable powder resin has an average particle diameter of 0.02 to 0.5 ㎛.
In paragraph 1,
A non-flammable and adsorption functional water-based inorganic paint composition, characterized in that the silica aerogel powder has an average particle size of 50 ㎛ or less.
delete In paragraph 1,
A non-combustible and absorbent functional water-based inorganic paint composition characterized in that the above diatomaceous earth is calcined to remove impurities.