JP2018184305A - Hydrotalcite compound, resin composition comprising the hydrotalcite compound blended therein, and molded article thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrotalcite compound capable of improving the thermal resistance of a resin, making the life of a resin longer, and making the recycling and reuse of a resin practicable without sacrificing economic efficiency, while maintaining characteristics of a resin such as excellent water resistance, acid resistance, alkali resistance, solvent resistance, flame retardancy, electric insulation, and moldability, as well as its desirable characteristics in the applications of a molded article thereof.SOLUTION: The hydrotalcite compound represented by the following chemical formula (a), is characterized in that the representative peak of the stretching vibration frequency of a hydroxy group measured by a Fourier transformation infrared spectrophotometer (FT-IR) is in a range of not lower than 3405 cmand not higher than 3435 cmand satisfies the particle size characteristics as defined by the following formulae (b) to (d): (a) MgAl(OH)A-mHO, (b) 5≤Sw≤15 (m/g), (c) 0.8≤Dp≤2.0 (μm), (d) D≤10.09 (μm). In the formulae, A represents a n-valent anion, x and m are each in a range of 0.267≤x≤0.290, and in a range of 0≤m<1 respectively, Sw represents a BET specific surface area (m/g), Dprepresents a 50% mean particle diameter (μm), and Drepresents the maximum particle diameter (μm).SELECTED DRAWING: None

Description

  The present invention relates to Mg-Al type hydrotalcites in which the ratio of two constituent metal elements is within a specific range, the hydroxyl group (OH) has a specific energy state, and further has specific powder properties. The present invention relates to a compound, a resin composition containing the compound, and a molded product thereof.

Hydrotalcite compounds ^usually represented by the composition formula _{^{M 2+ 1-x M 3+ x}} (OH) 2 A n- x / n · mH 2 O, the crystal structure has a layered structure, 2 It consists of a basic layer made of a composite hydroxide of a valence (M ²⁺ ) and a trivalent (M ³⁺ ) metal, and an intermediate layer having anions (A ⁿ⁻ ) and water between the basic layers.
The base layer is positively charged by the coordination of trivalent metal ions instead of a part of the divalent metal ions, and the anion intercalates between the layers of the base layer, so that the total charge is reduced. Neutralized.
Hydrotalcite compounds can adsorb anions between the surface layer and the interlayer of the basic layer, and are blended in synthetic resins, synthetic rubbers, ceramics, paints, papers, toners, etc. depending on their ability, and are used as halogen scavengers and receivers. It is used in a wide range of applications as an excellent stabilizer having an effect as an acid agent and an absorbent.

  Chlorine-containing resins such as polyvinyl chloride resin are excellent in water resistance, acid resistance, alkali resistance and solvent resistance, have flame resistance and electrical insulation, soften when heated, and harden when cooled. It is easy to process and the softness of the molded product itself can be changed by adding a plasticizer. Furthermore, it is inexpensive and has a wide range of applications, including clothing, wallpaper, bags, cushion materials, heat insulating materials, soundproofing materials, and protective materials. , Ropes, wire coverings, screen doors, packaging materials, water pipes, building materials, agricultural films, erasers, etc. are widely used.

However, when a chlorine-containing resin is exposed to heat, ultraviolet rays, etc., hydrogen chloride in the molecular chain is likely to be eliminated and a carbon double bond in the molecular chain is likely to be generated. It has the problem of attracting the elimination of hydrogen chloride from the molecular chain, creating a continuum of carbon double bonds in the molecular chain, increasing the coloration and brittleness, and reducing the commercial value. And measures for long-term use are necessary.
As countermeasures, various stabilizers have been added to improve and improve the stability of chlorine-containing resins, and various stabilizers such as lead-based, organotin-based, and metal soap-based have been proposed. It is used.
However, lead-based and organic tin-based stabilizers have been in the direction of being avoided in recent years because lead and tin themselves are harmful to the human body and the environment. Alternatives to zinc-barium stabilizers are in progress.
However, if a large amount of zinc metal soap stabilizer is added to the chlorine-containing resin for the purpose of improving heat resistance, the phenomenon of the resin called zinc burnt blackening or the zinc stabilizer also acts as an external lubricant. There are problems such as obstruction.

On the other hand, the molded product of chlorine-containing resin may be exposed to sunlight outdoors or indoors depending on the use, there is a problem of causing weather resistance deterioration such as coloring by ultraviolet rays or a decrease in brittleness, for the purpose of suppressing them, It contains antioxidants such as organic acid metal salts, inorganic metal salts, and phosphites, ultraviolet absorbers, light stabilizers, and the like.
However, the antioxidants, UV absorbers, and light stabilizers react with metal ions in the chlorine-containing resin and become colored, reducing the product value without producing the original color tone. The agent cannot exhibit its original performance, resulting in problems such as failure of the designed weather resistance.
In particular, under heating and pressurization conditions such as injection molding and extrusion kneading, the activity, desorption, movement, and reaction of the resin itself and the resin compound become active, and the reaction between metal ions and ultraviolet absorbers or light stabilizers, etc. Is further promoted.

This phenomenon occurs even when a hydrotalcite compound containing a small amount of other metal elements based on magnesium or aluminum is used as a stabilizing aid in a chlorine-containing resin. Problems such as coloring are solved by adding an auxiliary agent (Patent Documents 1 and 2).
Further, for example, a method for further preventing coloring without impairing the weather resistance by further adding a mercapto ester compound has been proposed (Patent Document 3).

In recent years, from the viewpoint of environmental protection and reduction of environmental impact, chlorine-containing resins are also strongly required to have long life, recycling, and reuse. As countermeasures, hydrotalcite compounds and other stabilizing aids, ultraviolet absorbers, light stabilizers, etc. Countermeasures by increasing various stabilizers have been proposed and studied.
However, simply increasing the compounding amount of various stabilizers such as hydrotalcite compounds and light stabilizers increases the chance of reaction between metal ions and light stabilizers, and the like. Deterioration of weather resistance due to a decrease in capability is not preferable.
Therefore, it has been proposed to increase the amount of β-diketone etc., which suppresses the reaction between various metal ions released from hydrotalcite compounds and light stabilizers, but they are lifted from resins called bleed and blooming. Since this phenomenon occurs, large-scale addition is not suitable for long-term applications such as electric wires.
Furthermore, for example, when blending them into a vinyl chloride resin, they are added to an epoxidized vegetable oil or the like from the viewpoint of handling to form a paste or a liquid. For example, dibenzoylmethane, which is a β diketone, is approved by the FDA. Stearoyl benzoylmethane, which is an FDA-approved β-diketone, has problems such as increasing the viscosity of the epoxidized vegetable oil and deteriorating its fluidity, making it difficult to handle ( Patent Document 4).
In addition, ester compounds of β-diketone and mercapto have a problem that they are more expensive than stabilizers such as hydrotalcite compounds as well as lead-based and metal soap-based stabilizers.

The hydrotalcite compound can replace the metal ion in the basic layer made of the metal hydroxide depending on the reaction conditions. For example, magnesium which is a divalent metal ion of the hydrotalcite compound described above. It is also possible to replace some or all with other metals.
For example, hydrotalcite represented by the composition formula Zn _x Al ₂ (OH) _{4 + 2x} CO ₃ · mH ₂ O (where 3.5 ≦ x ≦ 4.5, 0 ≦ m ≦ 4) in which all of magnesium is replaced with zinc It has been reported that the heat resistance of chlorine-containing resins is improved because the hydrotalcite compounds are superior in halogen absorption and acid-accepting ability to the conventional products including the hydrotalcite compounds described above. (Patent Document 5).

Also, a composition in which a part of magnesium is replaced with zinc (Mg _y Zn _z ) _1-x Al _x (OH) ₂ A _{x / n} · mH ₂ O (where 0.1 ≦ x ≦ 0.5, y + z = 1, 0.5 It has been proposed that hydrotalcite compounds having ≦ y ≦ 1, 0 ≦ z ≦ 0.5, A is an n-valent anion, and 0 ≦ m ≦ 1) improve the heat resistance of chlorine-containing resins (patents) References 6, 7).

However, this only focuses on improving the heat resistance when the above hydrotalcite compounds are blended with chlorine-containing resins, and the use of zinc as a raw material for these hydrotalcite compounds is considered. Absent.
In addition, since zinc is contained in the hydrotalcite compound, zinc may be liberated to cause the above-mentioned zinc burn, deterioration and weather resistance under heat and pressure conditions such as extrusion molding and injection molding. It does not contribute to the fundamental problem of preventing deterioration.

Zinc, which replaces part or all of magnesium in the hydrotalcite compounds mentioned above, is usually added during the reaction as chloride, sulfate or nitrate, and hydrotalcite is set under advanced reaction conditions. It is incorporated in the metal hydroxide layer, which is the basic layer of a similar compound.
Zinc chlorides, sulfates, and nitrates are obtained by reacting zinc oxide and metallic zinc with hydrochloric acid, sulfuric acid, and nitric acid. Most zinc oxide and metallic zinc are zinc blende (ZnS) and rhombozincite. It is obtained by refining zinc ore such as (ZnCO ₃ ) and then roasting to obtain zinc ore (ZnO), or by refining the zinc ore by a dry method or a wet method (electrolytic refining).
However, since zinc sulfate is in the form of zinc sulfate at the time of electrolytic refining, it is not necessary to refine even metallic zinc if the purpose is to obtain it.
However, since sphalerite contains cadmium and chalcopyrite contains lead, the refining process aimed at removing these harmful substances, protecting the environment, protecting workers, etc. is advanced, and zinc oxide and metal zinc are also included. Hydrochloric acid, sulfuric acid, and nitric acid to be reacted with the product are also required, resulting in high production costs.
Furthermore, in Japan, zinc itself is regulated by the Water Pollution Law, and the concentration (drainage standard) in the discharged water is regulated to 2 ml / L or less (promulgated on November 10, 2006). However, this has become a severe burden on costs and handling.
Therefore, it has been demanded to further improve the anion absorption capacity without using materials such as zinc, which are burdensome on the environment, cost, and handling.

In consideration of environment and economy, the present inventors have focused on the energy state in the crystal structure, hydrotalcite compounds with significantly improved heat resistance, and improved crystal structure and new sealing / trapping agents. The hydrotalcite composition which suppressed the detachment | desorption of the metal ion under heating-pressing conditions was proposed paying attention to (patent documents 8, 9).
However, although the former has suppressed metal ions under heat and pressure conditions, the latter has improved heat resistance compared to conventional hydrotalcite compounds and compositions. There has been a demand for a hydrotalcite compound comprising

Japanese Unexamined Patent Publication No. 57-80444 Japanese Unexamined Patent Publication No. 06-192520 JP 2013-10834 A Japanese Patent No. 5116141 Japanese Patent Publication No. 11-255973 WO99 / 01409 Publication WO099 / 05219 Publication Japanese Unexamined Patent Publication No. 2016-108177 JP 2016-108427 JP

The present invention provides various resins, particularly chlorine-containing resins, for the purpose of reducing recent environmental burdens, and has excellent water resistance, acid resistance, alkali resistance, solvent resistance, flame resistance, and electrical insulation properties. To provide hydrotalcite compounds that improve heat resistance without sacrificing economics, extend life, recycle, and reuse, while maintaining processability and properties according to the use of molded products Objective.
Specifically, for Mg-Al-type hydrotalcite compounds that do not use zinc or the like, anion adsorption is improved, metal ions such as magnesium and aluminum are further desorbed, and the particle size as powder or particles By improving the characteristics, for example, when blended in a chlorine-containing resin such as polyvinyl chloride resin, hydrogen chloride or chloride ions are more adsorbed to prevent the continuous formation of double bonds of molecular chains, and It aims at preventing coloring by reacting with stabilizers, such as antioxidant, a ultraviolet absorber, and a light stabilizer, by suppressing metal ions released from talcite compounds.
In addition, when the hydrotalcite compound is blended with a chlorine-containing resin, it does not impair the properties of the chlorine-containing resin even if a stabilizing aid such as β-diketone is not used or the amount used is extremely small. The purpose is to provide long-life, recycle and reuse.

  In view of such circumstances, the present inventors have intensively studied to achieve the above object, and as a result, the ratio of the two metal elements to be constructed is within a specific range, and the hydroxyl group (OH) has a specific energy state. Furthermore, the present inventors have found that an Mg-Al type hydrotalcite compound having specific powder properties is excellent in anion adsorbability while suppressing the separation and release of metal ions.

The present invention includes the following inventions.
(1) The hydrotalcite compound of the present invention is represented by the chemical formula of the following formula (a), and is representative of the stretching vibration frequency of the hydroxyl group (OH) obtained from a Fourier transform infrared spectrophotometer (FT-IR). peak in the range of 3405cm ^-1 or 3435cm ^-1 or less, the following (b) ~ hydrotalcite compound characterized by satisfying the particle size characteristics of (d).
(A) Mg _1-x Al _x (OH) ₂ A _{x / n} · mH ₂ O
(B) 5 ≦ Sw ≦ 15 (m ² / g)
(C) 0.8 ≦ Dp ₅₀ ≦ 2.0 (μm)
(D) D _Max ≦ 10.09 (μm)
In the formula, A represents an n-valent anion, and x and m represent values satisfying the following conditions.
0.267 ≦ x ≦ 0.290, 0 ≦ m <1
Sw: BET specific surface area measured by nitrogen adsorption method (m ² / g)
Dp ₅₀ : 50% average particle diameter (μm) of hydrotalcite compounds measured with a laser diffraction / scattering particle size distribution analyzer
D _Max : Maximum particle size (μm) of hydrotalcite compounds measured with a laser diffraction / scattering particle size distribution analyzer
(2) The hydrotalcite compound, wherein the hydrotalcite compound is surface-treated with at least one surface treatment agent selected from fatty acids, fatty acid metal salts, and coupling agents.
(3) The hydrotalcite compound has an acid dissociation constant of 1.5 to 3.5, at least one sequestering / trapping agent A selected from salts thereof, and a primary chelate stabilization constant of 6 or more against magnesium ions. A hydrotalcite compound characterized by being coated with either or both of the sequestering / capturing agent B selected from the chelating agents.
(4) A hydrotalcite compound wherein the sequestering / scavenging agent A is at least one selected from sulfurous acid, phosphonic acid, salicylic acid, maleic acid, and salts thereof.
(5) A hydrotalcite compound wherein the blocking agent / capture agent B is hydroxyethylidene diphosphonic acid.
(6) A resin composition comprising the hydrotalcite compound of any one of (1) to (5) above and a resin.
(7) A resin composition, wherein the resin is a polyvinyl chloride resin.
(8) A molded article comprising the resin composition according to (6) above.
(9) A molded article comprising the resin composition according to (7) above.

  According to the present invention, in a Mg-Al type hydrotalcite compound that does not use zinc or the like, the ratio of magnesium to aluminum is within a specific range, and is determined from a Fourier transform infrared spectrophotometer (FT-IR). The representative peak of the stretching vibration frequency of the hydroxyl group (OH) is within a specific range, and further having a specific particle size suppresses the elimination of metal ions such as magnesium and aluminum from hydrotalcite compounds, Contains metal ions and antioxidants, UV absorbers, light stabilizers and other stabilizers that react to prevent coloring, and has excellent anion absorption / adsorption ability and excellent particle size characteristics, so it contains chlorine such as polyvinyl chloride resin. When compounded in a resin, hydrogen chloride or chloride ions are quickly adsorbed to prevent the continuous formation of double bonds in the molecular chain and prevent deterioration of its mechanical properties. It hydrotalcite compound capable, as well as a molded article thereof said hydrotalcite compound by blending the resin composition.

The hydrotalcite compound of the present invention is represented by the chemical formula (a).
Examples of the n-valent anion A include divalent CO ₃ ²⁻ , SO ₄ ²⁻ , monovalent OH ⁻ , F ⁻ , Cl ⁻ , Br ⁻ , NO ₃ ⁻ and I ⁻ . Among these, CO ₃ ²⁻ is easily available, is economically effective, is advantageous in terms of environmental burden, and is stable as a hydrotalcite compound.

In the Mg-Al type hydrotalcite compound constituting the hydrotalcite compound of the present invention, the constituent metal elements are magnesium and aluminum, and the mixing ratio of both can be selected depending on the conditions at the time of production. .
The ratio of aluminum in the metal element of the hydrotalcite compound of the present invention, magnesium and aluminum is represented by x in the chemical formula of (a) above as a molar ratio, and is 0.267 ≦ x ≦ 0.290, preferably 0.274 ≦ x. By being in the range of ≦ 0.282, the amount of absorption and adsorption of anions increases, and magnesium desorption is suppressed.

  When x of the hydrotalcite compound of the present invention exceeds 0.290, for example, when blended in a polyvinyl chloride resin or the like, sufficient heat resistance is not exhibited, and the object of the present invention is not achieved. Although this mechanism is not clear in detail, the amount of anion adsorption is smaller than that of the hydrotalcite compound of the present invention, and the trapping, absorption, and acid acceptability of chlorine or chloride ions desorbed from the polyvinyl chloride resin are insufficient. The cause is thought to be the continuous formation of double bonds in the vinyl chloride resin. This applies to the hydrotalcite compounds mentioned in the prior art.

  When x of the hydrotalcite compound of the present invention is less than 0.267, for example, when blended with a polyvinyl chloride resin or the like, the heat resistance is excellent, but the pressure assuming an extrusion kneading process or an injection molding process Coloring occurs under heating conditions, and the object of the present invention is not achieved. Although details of this mechanism are not clear, metal ions such as magnesium and aluminum are more released and released from the resin than the hydrotalcite compounds of the present invention, and they are light stabilizers and antioxidants in the resin. It is thought that the reaction is promoted and coloring occurs.

In the hydrotalcite compound of the present invention, the representative peak κ (cm ⁻¹ ) of the stretching frequency of the hydroxyl group (OH) obtained by measurement with a Fourier transform infrared spectrophotometer FT-IR is 3405 ≦ κ ≦ 3435. And preferably 3415 ≦ κ ≦ 3425.

When a hydrotalcite compound having a representative peak κ of stretching frequency of OH obtained by measurement of FT-IR of less than 3405 cm ⁻¹ is blended with, for example, a polyvinyl chloride resin, the heat resistance is low and the effects of the present invention are obtained. Absent. Although this mechanism is not clear in detail, the amount of anion adsorbed by the hydrotalcite compound of the present invention is reduced, and the trapping, absorption, and acid acceptability of chlorine or chloride ions desorbed from the polyvinyl chloride resin are insufficient. The cause is thought to be the continuous formation of double bonds in the vinyl chloride resin. This applies to the hydrotalcite compounds mentioned in the prior art.
In the case of hydrotalcite compounds having a representative peak κ of stretching frequency of OH obtained by measurement of FT-IR exceeding 3435 cm ⁻¹ , heat resistance is good when blended with polyvinyl chloride resin, but pressure heating conditions Coloring occurs below. Details of this mechanism are not clear, but metal ions such as magnesium and aluminum are likely to be released from the hydrotalcite compound into the resin, and the reaction with light stabilizers and antioxidants is promoted to cause coloration. .

  It is clear that the magnitude of the representative peak κ indicating the stretching frequency of OH obtained by FT-IR measurement affects the adsorption rate and amount of anions, but the mechanism is unknown. κ is considered to be a representative value obtained by calculating not only the OH of the basic layer (metal hydroxyl layer) of the hydrotalcite compound, but also the OH stretching frequency of interlayer water contained between the layers. And it is thought that the stretching vibration wave number of OH of interlayer water is strongly influenced by the state of the hydroxyl group of the basic layer of the hydrotalcite compound.

Although it cannot be said that there is a strict correlation, when the value of x indicating the ratio of magnesium and aluminum in the metal element constituting the hydrotalcite compound of the present invention increases, the stretching vibration wave number of OH decreases, and x As the value of decreases, the stretching frequency of OH tends to increase. Since the vibration wave number is also energy, the ratio of the metal element of the hydrotalcite compound of the present invention affects the OH energy, which is considered to affect the absorption and adsorption of halogen. Details are not clear.
In addition, the FT-IR analysis in this invention was performed with the Hitachi high-tech sciences Fourier transform infrared spectroscopy apparatus Nicolet is50 FT-IR.

The BET specific surface area Sw (m ² / g) measured by the nitrogen adsorption method of the hydrotalcite compound is 5 ≦ Sw ≦ 15, preferably 8 ≦ Sw ≦ 12. When Sw is within this range, handling during production and use is improved, and further, for example, when blended in a chlorine-containing resin and exhibiting its effectiveness as a stabilizer or acid acceptor, Disperses well and facilitates the halogen adsorption reaction.

Those having a BET specific surface area Sw of less than 5 m ² / g are difficult to produce, and in that case, a large number of single particles are present in the hydrotalcite compound, and for example, polyvinyl chloride is present. Rapid absorption and adsorption of hydrogen chloride generated due to a shortage in the resin compounded in the resin, etc. is not performed, and it is possible to suppress desorption and release of hydrogen chloride from the molecular chain and continuous generation of double bonds. Not preferable. Moreover, it becomes a cause of a fracture | rupture of a resin composition or a molded object, or a mechanical weak point, and it becomes the cause of reducing the impact strength of a molded article, and a tensile strength, and is unpreferable.
When Sw exceeds 15m ² / g, fine particles increase in the hydrotalcite compound, causing aggregation during storage as a powder, when blended into a resin, or when molding a chlorine-containing resin composition. For example, when blended with polyvinyl chloride resin, etc., the hydrogen chloride generated due to insufficient number in the resin is not absorbed and adsorbed quickly, and the hydrogen chain is desorbed or doubled from the molecular chain. It is not preferable because the continuous formation of bonds cannot be suppressed, and the specific surface area from the particles increases, so that metal ions such as magnesium and aluminum are likely to be detached from the particles, which react with the light stabilizer and the antioxidant. This increases the chance of coloring, which is not preferable. Further, it is not preferable because it causes breakage of the composition or molded body or mechanical weakness and causes a decrease in strength properties.
In addition, the measurement of the nitrogen adsorption type BET specific surface area in this invention is MOUNTECH Co. , Ltd., Macsorb (registered trademark) HM model-1201.

The hydrotalcite compound of the present invention has a 50% average particle diameter Dp ₅₀ (μm) measured by a laser diffraction / scattering particle size distribution meter in the range of 0.8 ≦ Dp ₅₀ ≦ 2.0, preferably 0.8 ≦ Dp ₅₀ ≦ 1.5. Similarly, the maximum particle diameter D _Max (μm) measured by a laser diffraction / scattering particle size distribution meter is in the range of D _Max ≦ 10.09, and there is preferably little or little secondary aggregation.

  When the particle size characteristics of the hydrotalcite compound are within the above range, when blended in the resin and exhibit its effectiveness as a stabilizer, it is well dispersed in the resin and further contacts with halogen in the blended resin. The number and area are appropriate, halogen absorption / adsorption is likely to occur, and detachment of magnesium and aluminum can be reduced.

The above 50% average particle diameter Dp ₅₀ is less than 0.8 μm, and it is difficult to produce, and particles having a 50% average particle diameter Dp ₅₀ of less than 0.8 μm can be obtained by observation with an electron microscope or the like. Therefore, the surface energy of the particles is increased, and the particles are aggregated and stabilized, so that it is difficult to obtain particles having such values in the particle size measurement.
In addition, for example, when blended with polyvinyl chloride resin, magnesium and aluminum are easily separated from the particles, increasing the opportunity to react with light stabilizers and antioxidants. Agglomerates are easily formed when molding the resin, and the hydrogen chloride generated due to the insufficient number in the resin is not absorbed and adsorbed quickly. It is not preferable because it cannot suppress the continuous formation of the resin, and it is not preferable because it causes breakage of the composition or mechanical weakness and causes a decrease in strength properties such as impact strength and tensile strength of the resin molded product. It is done.
If the average particle diameter Dp ₅₀ exceeds 2.0 μm, a large amount of coarse particles will be present in the chlorine-containing resin, and when the particles are blended into a resin composition, the appearance of the composition will be impaired. However, it is not preferable because it causes breakage or mechanical weakness and decreases strength properties of the molded product.
Further, since the number in the chlorine-containing resin is reduced, the generated hydrogen chloride is not rapidly absorbed and adsorbed, and desorption of hydrogen chloride from the molecular chain cannot be suppressed, which is not preferable. In particular, when the particles are composed of aggregates, both the reduction of the halogen absorption / adsorption ability due to the decrease in the number and the promotion of the separation of the metal element due to the increase in the surface area occur, which is further undesirable.

When the maximum particle diameter D _Max exceeds 10.09 μm, a large number of coarse particles are present in the chlorine-containing resin regardless of the form of single particles or aggregated particles. Then, it becomes the cause of the fracture | rupture of the composition, or a mechanical weak point, and it becomes a cause which reduces strength physical properties, such as impact strength of a molded article, and tensile strength, and is unpreferable.
The average particle size Dp ₅₀ and the maximum particle size D _max of the hydrotalcite compound were measured with a Microtrac MT3300EX II laser diffraction / scattering particle size distribution meter manufactured by Microtrac Bell.

The hydrotalcite compound of the present invention can be produced by considering the following reaction conditions.
As described above, the stretching vibration frequency, average particle diameter Dp ₅₀ , maximum particle diameter D _Max , and BET specific surface area Sw of the hydroxyl group are determined by using a solution in which raw materials such as Mg, Al, CO ₃ and OH have been dissolved. The pH of the solution reaction when the hydrotalcite compound is produced by mixing, and the temperature, time, and stirring during the hydrothermal reaction of the resulting hydrotalcite compound reaction solution may be affected. It turns out.
However, the above conditions affect each physical property of the hydrotalcite compound of the present invention, and the magnitude and correlation of each effect are not necessarily clear. As a tendency, first, when the pH during the solution reaction is increased, the stretching vibration frequency of the hydroxyl group increases. Next, when the temperature during the hydrothermal reaction is increased, the average particle diameter Dp ₅₀ and the maximum particle diameter D _Max increase, and the BET specific surface area Sw tends to decrease. The maximum particle diameter D _Max increases when the temperature is lowered too much, but this is considered to be caused by aggregation of fine particles.
As the time during the hydrothermal reaction is increased, the average particle diameter Dp ₅₀ and the maximum particle diameter D _Max increase, and the BET specific surface area Sw tends to decrease. However, the maximum particle diameter D _Max increases as the time is short, but this is considered to be caused by aggregation of fine particles.
Regarding the stirring during the hydrothermal reaction, when the number of stirring is increased, the average particle diameter Dp ₅₀ tends to be small and the maximum particle diameter D _Max tends to be small.
Since the BET specific surface area Sw becomes large regardless of whether the number of stirring is large or small, it is necessary to select the number of stirring appropriately depending on the reaction apparatus and reaction conditions.

When the hydrotalcite compound of the present invention is molded into a resin and formed into a resin molded body, in addition to improving various physical properties such as durability and strength, the improvement of the original halogen absorption, the stability of the particles, Surface treatment (coating) is preferably performed with at least one surface treatment agent selected from fatty acids, fatty acid metal salts, and coupling agents for the purpose of improving dispersibility and affinity with the resin and imparting water repellency.
The surface treatment agent is preferably selected as appropriate from the viewpoints of the above various physical properties, applications, influence on the environment, handling properties, and cost.

  Examples of fatty acids include saturated fatty acids such as caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid; sorbic acid, elaidic acid, palmitoleic acid, oleic acid And unsaturated fatty acids such as linoleic acid, linolenic acid, cetreic acid, erucic acid, and ricinoleic acid. Among these, a mixed acid of stearic acid and palmitic acid is preferable in terms of reactivity with the hydrotalcite compound, particle stability, dispersibility, availability, and cost.

  Examples of metal salts of fatty acids include potassium laurate, potassium myristate, potassium palmitate, sodium palmitate, barium stearate, calcium stearate, zinc stearate, potassium stearate, cobalt (II) stearate, tin stearate (IV), saturated fatty acid salts such as sodium stearate, potassium stearate, lead (II) stearate; unsaturated fatty acid salts such as zinc oleate, potassium oleate, cobalt (II) oleate, sodium oleate It is done.

In addition, during or before the surface treatment of the hydrotalcite compound of the present invention, the above-described fatty acids include lithium, sodium, potassium, rubidium, beryllium, magnesium, calcium, strontium, barium, zinc, aluminum, lead, cobalt, A metal salt of a fatty acid may be appropriately prepared by mixing and reacting a compound having tin and an acyl group.
Among the above fatty acid metal salts, use of mixed soaps mainly composed of stearic acid or palmitic acid in terms of reactivity with hydrotalcite compounds, particle stability, dispersibility, availability, and cost Is preferred.

  Examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyl tris (β-methoxyethoxy) silane, γ-chloropropyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane. , Β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -Γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane and the like. Among these, vinyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, in terms of reactivity and stability with hydrotalcite compounds, improved affinity with resin, and cost, The use of 3-methacryloxypropyltrimethoxysilane is preferred.

Said surface treating agent is used individually or in combination of 2 or more types as needed. Further, the amount of the surface treatment agent to be treated is appropriately selected depending on the type and use of the resin in which the hydrotalcite compound obtained in the present invention is used. For example, when used as a stabilizer for a polyvinyl chloride resin. Usually, it is 0.01 to 15% by weight, preferably 0.05 to 8% by weight, based on 100% by weight of the polyvinyl chloride resin.
When the treatment amount of the surface treatment agent is less than 0.01% by weight, the effect of the surface treatment agent is not recognized, and it is not preferable because it only increases the cost. If the surface treatment amount exceeds 15% by weight, for example, when blended with polyvinyl chloride resin, fatty acid metal salts and the like work as external lubricants, making it impossible to work, and fatty acids and coupling agents are bleed and blooming. This is not preferable because a phenomenon referred to as “e.g.” tends to occur, and when a molded body is produced, the strength of the resin is significantly lowered, and even the shape of the molded body cannot be maintained in some cases.

  The hydrotalcite compound of the present invention is a sequestering / supplementary agent A selected from the above hydrotalcite compounds or surface-treated hydrotalcite compounds having an acid dissociation constant in the range of 1.5 to 3.5, and salts thereof. In addition, it is preferable to treat (coat) the particle surface with either or both of the blocking / capturing agent B composed of a chelating agent having a primary chelate stabilization constant of 6 or more with respect to magnesium.

  Examples of acids having an acid dissociation constant in the range of 1.5 to 3.5 include inorganic acids such as phosphonic acid (phosphorous acid), sulfurous acid, o-phosphoric acid, arsenic acid, chlorous acid, telluric acid, selenious acid, Examples include nitrous acid, hydrofluoric acid, and cyanic acid. Of these, sulfurous acid and phosphonic acid are preferred from the viewpoints of toxicity, stability, consideration for reducing environmental burden, solubility in water, availability, and the like.

  Examples of organic acids having an acid dissociation constant in the range of 1.5 to 3.5 include acetylsalicylic acid, inosine, 1,10-phenanthroline, 2,2-biviridine, 2-chloropropionic acid, 2-furancarboxylic acid, 3,4-dihydroxy Phenylalanine, 4-hydroxyproline, 4-methylpyrazole, DL-leucine, (d, RR) -tartaric acid, L-2,4-diaminenobutyric acid, L-alanyl-L-alanine, L-alanyl-L-phenylalanine, L -Alanylglycylglycylglycine, (L, β) -alanylglycylglycine, (L, β) -alanylglycine, L-histidylglycine, L-phenylalanylglycine, L-prolylglycine, L -Leucyl-L-tyrosine, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, m-nitriloaniline, 2-nitrobenzoic acid, 3-nitrobenzoic acid, 4 Nitrobenzoic acid, 2-benzenedicarboxylic acid, 3-benzenedicarboxylic acid, N, N′-dimethylglycine, N, N′-dimethylcysteine, 2-chloroaniline, 4-chloroaniline, 2-chlorobenzoic acid, 2- Fluorobenzoic acid, 2-bromobenzoic acid, 2-iodobenzoic acid, 4-anilinesulfonic acid, γ-L-glutamyl-L-cysteinylglycine, asparagine, aspartic acid, adenosine, alanine, arginine, isonicotinic acid, Isoleucine, oxaloacetate, ornithine, guanine, guanine, citric acid, glyoxylic acid, glycyl-DL-histidylglycine, glycyl-L-alanine, glycyl-L-histidine, glycyl-L-leucine, glycylglycyl-L-alanine, Glycylglycyl-L-histidine, glycylglycylglycyl-L-histi Glycylglycylglycylglycine, glycylglycylglycine, glycylglycine, glycine, glutamine, chloroacetic acid, sarkosylglycine, sarcosine, cyanoacetic acid, cysteine, citrulline, serine, thioglycolic acid, tyrosine, triethylenetetramine, Tryptophan, threonine, nicotinamide, nicotinic acid, valine, histidine, hypoxanthine, pyrazole, pyruvic acid, phenoxyacetic acid, phenylalanine, fumaric acid, purine, fluoroacetic acid, promoacetic acid, proline, maleic acid, malonic acid, mandelic acid, methionine , Mercaptoacetic acid, iodoacetic acid, lysine, malic acid and leucine. Among these, 2-aminobenzoic acid, 2-chlorobenzoic acid, 2-fluorobenzoic acid, in terms of toxicity, stability, consideration for reducing environmental impact, solubility in water, availability, etc. Salicylic acid, maleic acid, mandelic acid, malic acid, 2-nitrobenzoic acid and 2-bromobenzoic acid are preferred, and salicylic acid and maleic acid are particularly preferred.

  As inorganic acid salts with acid dissociation constants in the range of 1.5 to 3.5, inorganic acids include calcium phosphite, disodium hydrogen phosphite, disodium phosphite, ammonium hydrogen sulfite, sodium hydrogen sulfite, barium sulfite, bismuth sulfite, o-zinc phosphate, o-aluminum phosphate, o-ammonium cobalt phosphate, o-monoammonium phosphate, o-monopotassium phosphate, o-calcium monohydrogen phosphate, o-monosodium phosphate, o- Indium phosphate, o-estramustine phosphate disodium, o-silver phosphate, o-chromium monochromate (III), o-cobalt phosphate (II), o-samarium phosphate (III), o- Tripotassium phosphate, o-tricalcium phosphate, o-tricalcium phosphate, β-tricalcium phosphate, trisodium phosphate, triphosphate Nesium, o-trilithium phosphate, o-sodium ammonium hydrogen phosphate, o-potassium hydrogen phosphate, o-calcium hydrogen phosphate, o-sodium hydrogen phosphate, o-diammonium hydrogen phosphate, o-phosphate Dipotassium hydrogen, disodium o-phosphate, o-barium hydrogen phosphate, o-magnesium hydrogen phosphate, o-cerium (II) phosphate, o-iron (III) phosphate, o-copper phosphate ( II), o-sodium phosphate, o-ammonium dihydrogen phosphate, o-potassium dihydrogen phosphate, o-calcium dihydrogen phosphate, o-sodium dihydrogen phosphate, o-manganese dihydrogen phosphate (II ), Lithium dihydrogen phosphate, neodymium (III) phosphate, bismuth (III) phosphate, hydroxyamine phosphate, praseodymium (III) phosphate, o-phosphate pen Chloride, o-boron phosphate, o-magnesium ammonium phosphate, o-magnesium phosphate, o-manganese phosphate (II), o-manganese phosphate (III), o-tetracalcium phosphate, o-phosphate Lanthanum (III), potassium arsenate, calcium arsenate, disodium hydrogen arsenate, cesium dihydrogen arsenate, potassium chlorite, copper chlorite, sodium chlorite, barium chlorite, cadmium tellurite, Potassium tellurite, sodium tellurite, potassium selenite, sodium selenite, barium selenite, potassium nitrite, silver nitrite, diamine palladium palladium (II), diammonium platinum ammonium nitrite, sodium nitrite, fluorine Zinc fluoride, aluminum fluoride, antimony fluoride, ammonium fluoride, ytterbium fluoride, fluoride fluoride Bium, cadmium fluoride, potassium fluoride, potassium fluoride titanium, calcium fluoride, cobalt fluoride (II), cobalt fluoride (III), samarium fluoride, ytterbium fluoride oxide, terbium fluoride oxide, dysprobium fluoride , Mercury fluoride (II), ammonium hydrogen fluoride, potassium hydrogen fluoride, sodium hydrogen fluoride, scandium fluoride, tin fluoride (II), strontium fluoride, cesium fluoride, cerium fluoride (III), fluorine Tantalum (V), Titanium fluoride potassium, Thulium fluoride, Iron fluoride (III), Terbium fluoride (III), Copper fluoride (II), Sodium fluoride, Lead fluoride (II), Nickel fluoride (II), neodymium fluoride (II), barium fluoride, bismuth fluoride (III), praseodymium fluoride (III), holmium fluoride, Magnesium fluoride, manganese fluoride (III), molybdenum fluoride (VI), eurobium fluoride, lanthanum fluoride, lithium fluoride, lutetium fluoride, rubidium fluoride, ammonium cyanate, potassium cyanate, silver cyanate, Examples include sodium cyanate. Of these, sodium sulfite and sodium phosphonate are preferred from the viewpoints of toxicity, stability, consideration for reducing environmental burden, solubility in water, and availability.

  Examples of organic acid salts having an acid dissociation constant in the range of 1.5 to 3.5 include, for example, zinc salicylate, ammonium salicylate, calcium salicylate, silver salicylate, sodium salicylate, magnesium salicylate, monosalicytic acid salt such as sodium salicylate, and monochloroacetic acid sodium salt. And lactates such as zinc lactate, aluminum lactate, ammonium lactate, calcium lactate, silver lactate, sodium lactate, nickel lactate, barium lactate, magnesium lactate, magnesium lactate and lithium lactate. Of these, zinc salicylate and magnesium lactate are preferred.

  In addition, about the acid and its salt in the range of said acid dissociation constant 1.5-3.5, it is used individually or in combination of 2 or more types as needed, but it is more preferable to use in combination of 2 or more types, In particular, it is more preferable to use two kinds of inorganic acid salt and organic acid in combination.

When an acid or a salt thereof having an acid dissociation constant of less than 1.5 or more than 3.5 is blended in, for example, a polyvinyl chloride resin, coloring or weather resistance deterioration is liable to occur, which is not preferable.
Although these mechanisms are not clear, in the case of acids and salts thereof having an acid dissociation constant of less than 1.5, they react strongly with the surface of the hydrotalcite compound, and part of its crystal structure is impaired, resulting in hydrotalcite compounds. It is presumed that this is caused by promoting the elimination of metal ions from the compound and increasing opportunities for reaction with light stabilizers, antioxidants and the like.
If the acid dissociation constant exceeds 3.5 or an acid salt, even if it is added to the suspension of the hydrotalcite compound, the surface of the hydrotalcite compound cannot be sufficiently treated or coated, so that the hydrotalcite compound Since it is eliminated during production and discharged out of the system, for example, it is no different from separately adding those acids and salts and hydrotalcite compounds to polyvinyl chloride resin, so that they are hydrotalcite compounds of the present invention It is presumed that the surface cannot be efficiently reacted with the metal ions that are sequestered or desorbed, and the reaction with the light stabilizer or the antioxidant cannot be prevented.

About the addition amount of the acid which has said acid dissociation constant in the range of 1.5-3.5, and its salt, 0.01-3.0 weight% is preferable with respect to a hydrotalcite compound, respectively.
When the addition amount of the hydrotalcite compound is less than 0.01% by weight, the effect of the present invention does not appear as in the case of no addition. On the other hand, if it exceeds 3.0% by weight, for example, when it is heated during blending with polyvinyl chloride resin or when it is processed and molded, it may cause blackening or burnt itself, or too much activity may be imparted to deteriorate handling. In some cases, it is not preferable.

Examples of the chelating agent having a primary chelate stabilization constant for magnesium of 6 or more include iminodiacetic acid derivatives such as 2-hydroxybenzyliminodiacetic acid, phosphonomethyliminodiacetic acid, phosphonoethyliminodiacetic acid, N ′-( Orthohydroxycyclohexyl) Triacetic acids such as ethylenediaminetriacetic acid, ethylenediaminetetraacetic acid, ethylenediamine-N, N'-diacetic acid-N, N'-dipropionic acid, ethylenediamine-N, N'-diacetic acid-N, N ' -Di (2-propionic acid), 1,2-propylenediaminetetraacetic acid, trimethylenediaminetetraacetic acid, 1,2-cyclopentanediaminetetraacetic acid, trans-cyclohexane-1,2-diaminetetraacetic acid, orthophenylenediaminetetraacetate Acetic acid, bis (ethyl iminodiacetate) methylamine, trimethylenetetraamine Ethylenediaminetetraacetic acid such as Sa acetate, hydroxyethyl lysine engine phosphonic acid, include phosphonic acids such as nitrilotriacetic (methylene phosphonic acid), used alone or in combination. Of these, hydroxyethylidiene diphosphonic acid is preferred.
The upper limit of the primary chelate stabilization constant for magnesium is not particularly limited, but the larger the stability constant, the more complicated and large the structure of the molecule increases the cost. For example, it is added to a chlorine-containing resin. In some cases, about 8 is preferable, and about 7 is more preferable because there is a possibility of unexpected adverse effects on the system.

When a chelating agent having a primary chelate stabilization constant with respect to magnesium of less than 6 is blended in, for example, a polyvinyl chloride resin, coloring and weather resistance deterioration are caused, which is not preferable.
Although these mechanisms are not clear, when the first-order chelate stabilization constant for magnesium is less than 6, adding hydrotalcite compounds to, for example, a polyvinyl chloride resin as a hydrotalcite compound removes it from the hydrotalcite compound because of its low chelating ability. It is presumed that this is because the metal ions that are separated and released cannot react efficiently, and the reaction with various stabilizers such as a light stabilizer, an antioxidant, and an ultraviolet absorber cannot be prevented.

With respect to the addition amount of the chelating agent having a primary chelate stabilization constant of 6 or more with respect to magnesium, 0.01 to 3.0% by weight with respect to the hydrotalcite compound is preferable.
When the addition amount of the hydrotalcite compound is less than 0.01% by weight, the effect of the present invention does not appear as in the case of no addition. On the other hand, if it exceeds 3.0% by weight, for example, when it is heated at the time of blending into a polyvinyl chloride resin or at the time of processing molding, it may cause blackening or burning, which is not preferable.

The hydrotalcite compound of the present invention may be a method by which a hydrotalcite compound satisfying the above-described conditions can be obtained, and the method and conditions are not limited at all. Basically, it can be produced by a known method, but natural products are not problematic (for example, Japanese Patent Publication No. 46-2280 and Japanese Patent Publication No. 47-32198).
The order of addition / treatment of the above-described blocking / capturing agents A and B and the surface treatment agent may be determined first by handling, but it is preferable to use the surface treatment agent first.
The addition / treatment order of the blocking / capturing agents A and B and the surface treatment agent may vary in physical properties depending on the target chlorine-containing resin and application, but when used for, for example, vinyl chloride resin, the surface treatment agent first. It is preferable to surface-treat with.

The second of the present invention relates to a resin composition comprising the hydrotalcite compound of the present invention.
The hydrotalcite compound of the present invention is usually blended in an amount of 0.001 to 10 parts by weight, preferably 0.01 to 5 parts by weight per 100 parts by weight of the resin.

The resin in which the hydrotalcite compound of the present invention is used may be any resin as long as it is usually used as a molded product, but usually a thermoplastic resin is preferably used.
For example, polyolefins such as polymers or copolymers of C _{2 to} C ₈ olefins (α-olefins) such as polyethylene, polypropylene, ethylene / propylene polymers, polybutene, poly- (4-methylpentene-1), etc. Resins, copolymers of these olefins and dienes, ethylene-acrylate copolymers, polystyrene, ABS resins, AAS resins, AS resins, MBS resins, ethylene-vinyl chloride copolymer resins, ethylene-vinyl acetate copolymers Resin, ethylene-vinyl chloride-vinyl acetate copolymer resin, polyvinylidene chloride, polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene, vinyl chloride-propylene copolymer, polyvinyl acetate, phenoxy resin, polyacetal, polyamide, polyimide , Polycarbonate, polysulfone, polyphenylene oxa De, polyphenylene sulfide, polyethylene terephthalate, include polybutylene terephthalate and methacrylonitrile based resin or the like, and these are used singly or in combination of two or more, if necessary.

Among these thermoplastic resins, examples of excellent thermal deterioration prevention effect and mechanical strength retention property by the hydrotalcite compound of the present invention are polyolefins or copolymers thereof, and halogen-containing resins, specifically Is polypropylene resin such as polypropylene homopolymer, ethylene propylene copolymer, high density polyethylene, low density polyethylene, linear low density polyethylene, ultra low density polyethylene, EEA (ethylene ethyl acrylate resin), EVA (ethylene vinyl acetate) Resin), EMA (ethylene acrylic methyl copolymer resin), EAA (ethylene acrylic acid copolymer resin), polyethylene resins such as ultra-high molecular weight polyethylene, and C ₂ such as polybutene and poly (4-methylpentene-1) polymers or copolymers such as polyolefins -C ₆ is It is below.
Among these, polyethylene, polypropylene, polybutene, poly (4-methylpentene-1) or a copolymer thereof is particularly preferable. Furthermore, biodegradable plastics such as polylactic acid resin, polybutylene succinate, polyamide 11 and polyhydroxybutyric acid and biomass plastics can also be used.

These polyolefin resins contain halogens derived from Ziegler-based polymerization catalysts in the resins. However, since the hydrotalcite compounds of the present invention are extremely excellent in absorption and acid reception of these halogens, The effect of suppressing the thermal degradation caused by is excellent.
In addition, the hydrotalcite compound of the present invention is excellent in the effect of suppressing thermal deterioration for the same reason with respect to a polyvinyl chloride resin or a copolymer thereof.

  Furthermore, thermosetting resins such as epoxy resin, phenol resin, melamine resin, unsaturated polyester resin, alkyd resin and urea resin, and EPDM, butyl rubber, isoprene rubber, SBR, NBR, chlorosulfonated polyethylene, NIR, urethane rubber, The present invention can also be applied to synthetic rubbers such as butadiene rubber, acrylic rubber, silicone rubber, and fluorine rubber.

There are no particular restrictions on the method of blending the hydrotalcite compounds of the present invention into the resin, and for example, by the same means as known methods for blending various stabilizers and fillers used in the above-mentioned resins into these resins. In addition to other resin compounding agents or separately, it may be compounded in the synthetic resin so as to be as uniform as possible.
Specifically, a method of blending using a known mixing device such as a ribbon blender, a high speed mixer, a kneader, a pelletizer, an extruder, or a suspension of a heat deterioration agent containing a hydrotalcite compound as an active ingredient. An example is a method of adding to the slurry after polymerization while stirring, mixing and drying.

The resin containing the hydrotalcite compound of the present invention may contain other additives in addition to the above components as long as the efficacy of the present invention is not impaired.
Examples of such additives include antioxidants, antistatic agents, pigments, foaming agents, plasticizers, fillers, reinforcing agents, flame retardants, crosslinking agents, light stabilizers, ultraviolet absorbers, lubricants, and the like other than the above. Inorganic or organic stabilizers may be mentioned.

EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example and a comparative example, this invention is not limited at all by these examples.
In the examples and comparative examples of the present invention, the representative peak of the stretching vibration wave number of the hydroxyl group of the hydrotalcite compound obtained by FT-IR analysis is a Fourier transform infrared spectrometer Nicolet is50 manufactured by Hitachi High-Tech Science Co., Ltd. Measured by FT-IR.
The average particle size Dp ₅₀ and the maximum particle size D _max of the hydrotalcite compound were measured with a Microtrac MT3300EX II laser diffraction / scattering particle size distribution meter manufactured by Microtrac Bell.
The BET specific surface area Sw of the hydrotalcite-type compound is MOUNTECH Co. , Ltd., Macsorb (registered trademark) HM model-1201.
The compositional analysis of hydrotalcite compounds was measured and calculated by ICP-MS method, CO ₃ by CHN measurement method, and (OH) ₂ and H ₂ O amounts by calorimetric analysis method.

Example 1
A 3.5 mol / L magnesium chloride solution and a 1.0 mol / L aluminum sulfate solution are mixed to prepare a mixture of magnesium and aluminum at a molar ratio of 4: 1 and 5: 2, and each mixture is kept at 20 ° C. Adjusted.
Next, a 18.08 mol / L sodium hydroxide solution and a 0.51 mol / L sodium carbonate solution were prepared in a mixed solution having a molar ratio of hydroxyl group to carbonate group of 6.4: 1 and adjusted to 20 ° C.
Each of the above magnesium and aluminum mixing ratios of 4: 1 and 5: 2 is mixed with each of the magnesium chloride-aluminum sulfate mixed liquid and the above sodium hydroxide-sodium carbonate mixed liquid while maintaining the pH at 10.0 ± 0.1 to react. Then, a reaction solution of two types of hydrotalcite compounds (the former is called the reaction solution A and the latter is called the reaction solution B) was prepared.
Next, the reaction solution A and the reaction solution B were put into the autoclave in the ratio of 1: 4 in the order, and the mixture was stirred at 105 rpm and maintained at 160 ° C. for 12 hours, followed by hydrothermal reaction, and then released to room temperature. It was cooled to obtain a hydrotalcite compound suspension.
The obtained suspension of hydrotalcite compound was dehydrated with a press filter and washed with tap water, and the washing was terminated when the washing wastewater became 20 μS / cm higher than the electric conductivity of tap water.
The washed presscake-like hydrotalcite compound was dried in a gear oven at 135 ° C. for 12 hours and then pulverized with a Koroflex pulverizer to obtain a dry powder of a surface-treated hydrotalcite compound.
When a part of the suspension of hydrotalcite compound was collected and analyzed and measured, the chemical formula was Mg _0.732 Al _0.268 (OH) ₂ (CO ₃ ) _0.15 · 0.53H ₂ O, BET specific surface area Sw The particles were 14.4 m ² / g, average particle diameter Dp ₅₀ 1.93 μm, and maximum particle diameter D _Max 10.09 μm.
Table 1 shows the reaction conditions, chemical formula and various physical properties of the obtained hydrotalcite compounds.

Examples 2-16, Comparative Examples 1-9
Mixing ratio of magnesium chloride solution and aluminum sulfate solution at the time of solution reaction, pH at the time of reaction between the mixed solution and a mixed solution of sodium hydroxide and sodium carbonate, two types of hydrotalcite reaction solution A and reaction solution The mixing ratio with B, the temperature during hydrothermal reaction, the time, and stirring were changed as shown in Table 1, and the same operation as in Example 1 was carried out. A dry powder was obtained.

Example 17
After washing the hydrotalcite compound obtained in Example 1, the presscake-like hydrotalcite compound is again suspended in water, the liquid temperature is adjusted to 80 ° C., and the hydrotalcite compound Add after dissolving a commercial soap of 65% sodium stearate-35% sodium palmitate in water at 80 ° C, equivalent to 2.2% by weight of the hydrotalcite compound in the suspension Then, the surface treatment of the hydrotalcite compound was performed by stirring for 60 minutes.
Thereafter, 0.18% by weight of salicylic acid (A1: acid dissociation constant 2.81), 0.18% by weight of sodium sulfite (A2: acid dissociation constant 1.86), 0.2% by weight of hydroxyethylidene diphosphonic acid (based on hydrotalcite compound) B: Dissolve chelate stabilization constant 6.55) in water and add to the surface-treated hydrotalcite compound solution in the order of a salicylic acid solution, a sodium sulfite solution, and a hydroxyethylidiene diphosphonic acid solution every 30 minutes under stirring. A hydrotalcite compound suspension was obtained.
The obtained suspension of surface-treated hydrotalcite compound was dehydrated again with a press filter to form a cake, then dried in a gear oven at 135 ° C for 12 hours, and then crushed with a Koroflex pulverizer. A dry powder of a hydrotalcite compound was obtained.
Table 2 shows the surface treatment agent, blocking / trapping agent type, treatment / addition amount of the hydrotalcite compound used.

Examples 18-36
The press cake obtained after washing the hydrotalcite compounds obtained in Examples 1, 6, and 16 was again suspended in water, and the surface treatment agent, the blocking / trapping agent, and the treatment amount were changed to Table 2. The surface-treated hydrotalcite compounds shown in Table 2 were obtained by operating in the same manner as in Example 17.
The acid dissociation constants of ammonium salicylate and sodium salicylate used as the blocking / capturing agent A1 in Examples 30 and 31 were 2.81, the same as the acid, and the acid dissociation of maleic acid used as the blocking / capturing agent A1 in Example 33. The constant is 1.75.
The acid dissociation constant of phosphonic acid used as the sequestering agent A2 in Examples 24 and 26 is 1.50, and sulfite is 1.86, the same as sodium sulfite.
The chelate stabilization constant for magnesium of 5 sodium nitrotri (methylenephosphonate) used as chelating agent B in Example 28 is 7.20.

Examples 37-72, Comparative Examples 10-18
After mixing the hydrotalcite compounds obtained in Examples 1 to 36 and Comparative Examples 1 to 9 with the following composition, pellets were produced with a kneading extruder set at 161 ° C.
(Composition composition)
Polyvinyl chloride resin (degree of polymerization 1300) 100 parts by weight
DOP 50 parts by weight Zinc stearate 0.5 parts by weight Hydrotalcite compound 2.5 parts by weight Further, the obtained pellets were produced using a 160 ° C. roll or a pressure press with a heater to prepare a sheet having a thickness of 1 mm. About the obtained sheet | seat, the heat resistance deterioration test, the heat-resistant press test, the sink mark, and foaming resistance were evaluated by the following method, and the volume resistivity was measured. The results are shown in Tables 3-6.

<Heat resistance degradation test>
Cut the prepared sheet into 20mm x 10mm and place it in a gear oven (Gabeh GPHH-100 manufactured by Tabai Espec Co., Ltd.) with a damper opening of 50% at 190 ° C and take it out every 15 minutes until the test piece turns black Seeking time.

<Heat-resistant press test>
The produced sheet was cut into 20 mm × 20 mm, and the sheet was taken out after being heated at 190 ° C. for 5 minutes and 30 minutes while applying pressure using a pressure press with a heater, and the hue of the sheet was measured.
The device used was a colorimetric color difference meter ZE2000 manufactured by Nippon Denshoku Industries Co., Ltd., and the YI value of transmitted light was evaluated.

<Sink marks and foam resistance>
Cut out the prepared sheet into 20mm x 20mm, apply pressure using a pressure press with a heater, take out the sheet after heating it at 190 ° C for 5 and 30 minutes, and take it out. Bubbles, dents and sheets on the surface called sink marks The voids inside were observed and evaluated in the following five stages.
5: No sink marks / bubbles in the sheet 4: Fine (0.1 mm or less) bubbles are observed at the edge of the sheet 3: 2 to 5 sink marks and fine bubbles are observed in the sheet 2: Sheet 6 or more sink marks of about 1 to 2 mm are observed in the sheet 1: Remarkable sink marks and bubbles are observed on the entire sheet surface

<Volume resistivity test>
The measurement was performed according to the following procedure in accordance with JIS K6723. That is, a sheet with a length of 120 mm or more is punched from the prepared sheet, the thickness of the test piece is measured at five locations, the average value is taken as the thickness, and the test apparatus and the punched sheet are placed in a thermostat set at 30 ° C. for 30 minutes or longer. The volume resistivity is measured at an applied voltage of 500 V and a charging time of 1 minute. The apparatus used was Agilent Technologies' 4339B High Resistance Mater.

  In the hydrotalcite compound of the present invention, the ratio of magnesium and aluminum is within a specific range, the hydroxyl group (OH) has a specific energy state, and further defines the size and dispersibility as powder or particles. As a result, it has better anion adsorption than conventional hydrotalcite compounds and compositions, and suppresses the desorption and release of magnesium ions, which are their drawbacks, such as chlorine such as resins such as polyvinyl chloride resin. When blended with a resin, the molecules such as polyvinyl chloride resin by ultraviolet rays or heating, etc. are prevented while preventing the coloration caused by the reaction between the desorbed / free magnesium ions and other additives and the ability of the stabilizer to decrease. It is useful as a stabilizer that absorbs hydrogen chloride or chloride ions leaving the chain.

Claims (9)

The representative peak of the stretching vibration frequency of the hydroxyl group represented by the chemical formula of the following formula (a) and determined by a Fourier transform infrared spectrophotometer (FT-IR) is in the range of 3405 cm ⁻¹ or more and 3435 cm ⁻¹ or less. A hydrotalcite compound characterized by satisfying the particle size characteristics of (b) to (d).
(A) Mg _1-x Al _x (OH) ₂ A _{x / n} · mH ₂ O
(B) 5 ≦ Sw ≦ 15 (m ² / g)
(C) 0.8 ≦ Dp ₅₀ ≦ 2.0 (μm)
(D) D _Max ≦ 10.09 (μm)
In the formula, A represents an n-valent anion, and x and m represent values satisfying the following conditions.
0.267 ≦ x ≦ 0.290, 0 ≦ m <1
Sw: BET specific surface area measured by nitrogen adsorption method (m ² / g)
Dp ₅₀ : 50% average particle diameter (μm) of hydrotalcite compounds measured with a laser diffraction / scattering particle size distribution analyzer
D _Max : Maximum particle size (μm) of hydrotalcite compounds measured with a laser diffraction / scattering particle size distribution analyzer   The hydrotalcite compound according to claim 1, wherein the hydrotalcite compound is surface-treated with at least one surface treatment agent selected from fatty acids, fatty acid metal salts, and coupling agents.   The hydrotalcite compound is composed of at least one sequestering / capturing agent A selected from acids having an acid dissociation constant of 1.5 to 3.5 and salts thereof, and a chelating agent having a primary chelate stabilization constant for magnesium ions of 6 or more. The hydrotalcite compound according to claim 1 or 2, wherein the hydrotalcite compound is coated with either or both of at least one sequestering / capturing agent B selected.   The hydrotalcite compound according to claim 3, wherein the sequestering / capturing agent A is at least one selected from sulfurous acid, phosphonic acid, salicylic acid, maleic acid, and salts thereof.   The hydrotalcite compound according to claim 3, wherein the blocking / capturing agent B is hydroxyethylidene diphosphonic acid.   A resin composition comprising the hydrotalcite compound according to any one of claims 1 to 5 and a resin.   The resin composition according to claim 6, wherein the resin is a polyvinyl chloride resin. The molded object which consists of a resin composition of Claim 6. The molded object which consists of a resin composition of Claim 7.