JP2762282B2 - Submicron Y-type zeolite and method for producing the same - Google Patents

Description

The present invention relates to a novel submicron Y-type zeolite having a small particle size, a method for producing the Y-type zeolite, and an antibacterial zeolite using the Y-type zeolite.

[Conventional technology]

In recent years, kneading of zeolite into resin has been performed. In particular, when processing to a thickness of several tens of μm such as a film or fiber, a zeolite particle having a thickness of 0.5 μm or less is awarded. In that case, the dispersibility of the zeolite in the resin is good, pinholes are hardly generated in the kneaded resin, which is advantageous in the case of a film, and in the case of a fiber, yarn breakage is less likely to occur. There are advantages such as. Further, zeolite having a small particle diameter has an advantage that the ion exchange rate is high. Therefore, a method for producing fine zeolite has been proposed.

For example, Japanese Patent Application Laid-Open No. 55-90417 discloses a method in which the reaction is carried out under a pressure of 7 kg / cm ² · G. A method is disclosed. However, the zeolite particle diameter obtained by either method is 0.6 μm or more. Further, the former requires a special pressure vessel such as an autoclave, and the latter method is not suitable for mass production by scale-up because of difficulty in controlling the temperature rise.

[Problems to be solved by the invention]

Accordingly, an object of the present invention is to provide a fine Y-type zeolite having a particle diameter of 0.4 μm or less, and when the antibacterial zeolite is used, the kneaded resin does not discolor and the degree of discoloration increases with time. The object of the present invention is to provide a Y-type zeolite free from zeolites.

[Means for solving the problem]

In the present invention, SiO ₂ / Al ₂ O ₃ (molar ratio) is 4.0 or more,
Also, the present invention relates to a submicron Y-type zeolite having a particle diameter of substantially 0.4 μm or less.

 Hereinafter, the present invention will be described.

The feature of the submicron Y-type zeolite of the present invention is that SiO ₂
/ Al ₂ O ₃ (molar ratio) is 4.0 or more, preferably 4.1 to 5.8, and the particle diameter is substantially 0.4 μm or less. Here, “the particle diameter is substantially 0.4 μm or less”
The expression means that 95% or more, preferably 99% or more, of the total number of particles observed by photography with a scanning electron microscope has a fixed direction diameter of 0.4 µm or less. The particle size of the preferred zeolite of the present invention is at most 0.4 μm, usually 0.0
5 to 0.4 μm.

The zeolite of the present invention has the same properties as those of a Y-type zeolite.

Hereinafter, the method for producing the Y-type zeolite of the present invention will be described. That is, the zeolite of the present invention comprises: (a) a step of preparing a raw material slurry containing an aluminum compound, a silicon compound and an alkali metal compound; and (b) generating a zeolite nucleus while maintaining the raw material slurry at a temperature of 40 ° C. or lower. And (c) maintaining the slurry containing the zeolite nuclei at a temperature equal to or higher than the zeolite nucleation temperature to grow zeolite crystals.

As the raw material slurry, a slurry containing an aluminum compound, a silicon compound and an alkali metal compound is used.
Examples of the aluminum compound include aluminum hydroxide, sodium aluminate, and alumina gel. Examples of the silicon compound include sodium silicate and colloidal silica. Further, examples of the alkali metal compound include sodium hydroxide and potassium hydroxide. Further raw _{slurry, SiO 2 / Al 2 O 3} ( molar ratio)
Is 11 to 20, preferably 10.5 to 15, H ₂ O / Al ₂ O ₃ (molar ratio) is 220 to 300, preferably 230 to 250, and M ₂ O
/ Al ₂ O ₃ (molar ratio) (M is an alkali metal such as sodium or potassium) is preferably 6 to 10, preferably 6.5 to 8.

In the present invention, the raw material slurry is maintained at a temperature of 40 ° C or lower, preferably 15 to 35 ° C, to generate zeolite nuclei. The retention time depends on the temperature and the reaction scale, but is, for example, preferably 8 to 48 hours, and more preferably 12 to 24 hours. During the holding, the slurry can be stirred by a conventional method.

Next, the slurry containing the zeolite nucleus is maintained at a temperature equal to or higher than the zeolite nucleation temperature. When the zeolite nucleation temperature is 35 ° C., the holding can be performed, for example, at 35 to 85 ° C. The retention time depends on the temperature and the reaction scale, but is, for example, 10 to 48.
The time is preferably 15 to 36 hours.
Further, during the holding, the slurry can be stirred by a conventional method.

The submicron Y-type zeolite thus obtained can be made into a product by performing separation, washing, drying, etc. from the slurry by a conventional method.

Submicron Y-type zeolite of the present invention is shown as general formula _{XM 2 O · Al 2 O 3} · YSiO 2 · ZH 2 O. Here, M represents an ion-exchangeable ion and is an alkali metal ion. X and Y each represent a metal oxide, a silica coefficient, Z represents the number of waters of crystallization, X represents 0.9 to 1.1, and Y represents
Is 4-7 and Z is 0-5.

In particular, Al ₂ O ₃ / YSiO ₂ (molar ratio) in the composition formula of zeolite
Is 4.0 or more in terms of stability such as acid resistance, heat resistance, and weather resistance. The submicron Y-type zeolite of the present invention obtained as described above may be used in various fields where fine Y-type zeolite is used, for example, resin additives such as films, fibers, sheets, and various molded articles, and fillers. Can be.

Further, the submicron Y-type zeolite of the present invention can be used as an antibacterial zeolite in which some or all of the ion-exchangeable ions in the zeolite are replaced with antibacterial metal ions. Further, the submicron Y-type zeolite of the present invention can be used as an antibacterial zeolite obtained by substituting a part or all of the ion-exchangeable ions in the zeolite with an antibacterial metal ion and further subjecting the zeolite to acid treatment.

These antibacterial zeolites of the present invention are obtained by substituting some or all of the ion-exchangeable ions, for example, sodium ions and potassium ions, in the above-mentioned submicron Y-type zeolite with antibacterial metal ions. Examples of antibacterial metal ions include silver, copper, zinc, mercury, tin, lead, bismuth, cadmium, chromium or thallium ions, preferably silver, copper or zinc ions.

From the viewpoint of antibacterial properties, it is appropriate that the above antibacterial metal ions are contained in the zeolite in an amount of 0.1 to 15%.
0.1 to 15% of silver ion and 0.1 to 0.1% of copper ion or zinc ion
An antimicrobial zeolite containing 18% is more preferred. In addition, in this specification,% means weight% of 110 degreeC dry basis.

Hereinafter, the method for producing the antibacterial zeolite of the present invention will be described.

The antibacterial zeolite of the present invention is prepared by bringing zeolite into contact with a mixed aqueous solution containing antibacterial metal ions such as silver ions, copper ions, and zinc ions prepared in advance, and ion-exchangeable ions in the zeolite and the ions. Let it be replaced. The contact can be performed at 10 to 70 ° C, preferably 40 to 60 ° C, for 3 to 24 hours, preferably 10 to 24 hours by a batch system or a continuous system (for example, a column method). The pH of the mixed aqueous solution is suitably adjusted to 3 to 10, preferably 5 to 7.

This adjustment is preferable because precipitation of silver oxide or the like on the zeolite surface or in pores can be prevented. Each ion in the mixed aqueous solution is usually supplied as a salt.
For example, silver ions are silver nitrate, silver sulfate, silver perchlorate, silver acetate, diammine silver nitrate, diammine silver sulfate, etc., and copper ions are copper (II) nitrate, copper perchlorate, copper acetate, potassium tetracyanocuprate, Zinc ions such as copper sulfate are zinc nitrate (I
I), zinc sulfate, zinc perchlorate, zinc thiocyanate, zinc acetate, etc., mercury ions, mercury perchlorate, mercury nitrate, mercury acetate, etc., tin ions, tin sulfate, etc., and lead ions, lead sulfate, Bismuth ions, such as lead nitrate, bismuth chloride, bismuth iodide, etc., cadmium ions, cadmium perchlorate, cadmium sulfate, cadmium nitrate, cadmium acetate, etc., chromium ions, chromium perchlorate, chromium sulfate, ammonium chromium nitrate, Thallium ions such as chromium acetate are thallium perchlorate, thallium sulfate, thallium nitrate,
It can be supplied as thallium acetate or the like.

The content of antibacterial metal ions such as silver ions in zeolite can be appropriately controlled by adjusting the concentration of each ion (salt) in the mixed aqueous solution. For example, when the antibacterial zeolite contains silver ions and zinc ions, the silver ion concentration in the mixed aqueous solution is 0.002 M / l to 0.15
By setting the M / l and the zinc ion concentration to 0.15 M / −2.8 M / l, an antibacterial zeolite having a silver ion content of 0.1 to 5% and a zinc ion content of 0.1 to 18% can be appropriately obtained.

In the present invention, ion exchange can also be performed by using an aqueous solution containing each ion alone in addition to the mixed aqueous solution as described above and sequentially contacting each aqueous solution with zeolite. The concentration of each ion in each aqueous solution can be determined according to each ion concentration in the mixed aqueous solution.

It should be noted that ion exchange of ions without suitable aqueous salts such as tin and bismuth can be carried out by using an organic solvent solution such as alcohol or acetone so as to react so that hardly soluble basic salts do not precipitate.

In the present invention, the acid treatment is performed for the purpose of preventing discoloration due to light and heat when kneading the antibacterial zeolite into an organic polymer such as a resin. Or at any time after the end of the antibacterial metal ion exchange. As a treatment method, after dissolving an acid substance in water or the like and adjusting the concentration to an appropriate solution,
It can be performed by a conventionally known method such as adding to a reaction tank or a filtration device. Examples of the acid used include nitric acid, sulfuric acid,
Inorganic acids such as hydrochloric acid, perchloric acid, phosphoric acid, and carbonic acid and organic acids such as formic acid, acetic acid, propionic acid, and oxalic acid can be cited. From the viewpoint, nitric acid is preferred.

0.02-4 mol, preferably 1 mol of zeolite
Discoloration can be prevented by treating with 0.1 to 1 mol of acid. The acid solution is preferably set to 0.01-1N (specific concentration) from the viewpoint of not destroying the structure of the Y-type zeolite. After the acid treatment, the substrate is washed with water until no anion of the used acid substance is detected.

The zeolite after the ion exchange is thoroughly washed with water and then dried. Drying is preferably performed at 105 ° C. to 115 ° C. under normal pressure or at 70 ° C. to 90 ° C. under reduced pressure (1-30 torr).

The antibacterial activity of the antibacterial zeolite of the present invention thus obtained can be evaluated by measuring the minimum inhibitory concentration (MIC) against various common bacteria, fungi and yeasts.

 The following bacteria can be used for the test.

Bacillus cereus var mycoides, ATCC 11778 Escherichia coli, IFO 3301 Shademonas aeruginosa, IIDP-1 Staphylococcus aureus Streptococcus faecalia (RATCC 8043) Aspergillus niger, IFO 4407 Aureobasidium pulluans, IFO 6353 Ketimium globosum Gliocladium virens, IFO 6355) Penicillium funiculosum, IFO 6345 Candida albiacans, IFO 1594 Saccharomyces cerevisiae, IFO 1950 Test samples of sexual zeolite plate medium supplemented with arbitrary concentration, and smear culturing inoculating bacteria solution is made by examining the minimum concentration of the test sample, such as growth is prevented.

The present invention also provides an antibacterial resin composition containing the above antibacterial zeolite and a resin. As the resin, for example,
Polyester, polypropylene, vinyl chloride resin, ABS
Resin, polyester, polyvinylidene chloride, polyamide polystyrene, polyacetal, polyvinyl alcohol, polycarbonate, acrylic resin, fluororesin, polyurethane elastomer, polyester elastomer,
Phenol resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, urethane resin, rayon, cupra, acetate, natural rubber, synthetic rubber and EV
At least one resin selected from the group consisting of the A resin can be mentioned. The antimicrobial resin composition of the present invention can be obtained by directly kneading the antimicrobial zeolite into the resin or coating the resin on the surface. From the viewpoint of adding antibacterial, antifungal, and antialgal functions to the above resin
Suitably, it contains 0.05-80%, preferably 0.1-80%, of an antibacterial zeolite. The MIC of the antibacterial resin composition can be performed in the same manner as described above. Further, from the viewpoint of substantially preventing discoloration of the resin, the content of the antibacterial zeolite is preferably set to 0.1 to 8%.

The antibacterial zeolite of the present invention can be used in various fields.

Applications for resin include clothing, underwear, interior products, textiles such as shoes, food packaging, kitchen, bath products,
It can be used in the field of film and sheet processing such as sanitary goods.

In the field of water system, it can be used as a water purifier, cooling tower water, various types of cooling water, an antibacterial and anti-algal agent for metalworking oils, and also as a prolonged life of cut flowers.

In the field of paints and adhesives, oil-based paints, lacquers, varnishes,
Alkyl resin, amino alkyd resin, vinyl resin, acrylic resin, epoxy resin, urethane resin, water, powder, chloride rubber, phenol, etc. It is possible to add antibacterial, antifungal and antialgal functions to the coating by coating on the film surface. In the architectural field, it is possible to add antibacterial, fungicidal and anti-algal functions by mixing with joint materials, wall materials, tiles, or the like, or by coating the surfaces thereof.

Wet tissue, paper packaging, cardboard,
It is possible to add an antibacterial and antifungal function to these papers by making or coating them on a sheet of paper or freshness-keeping paper, and it can also be used as a slime control agent especially in the papermaking field.

The antibacterial zeolite of the present invention is not limited to the above-mentioned various fields, but can be used in any field that requires prevention of generation and growth of microorganisms such as general bacteria, fungi and algae.

〔The invention's effect〕

According to the present invention, a particle size measured by a scanning electron microscope (SEM) is at most 0.4 μm, and SiO ₂ / Al ₂ O
₃ A novel submicron Y-type zeolite having a molar ratio of 4.0 or more is provided. Further, the antibacterial zeolite using the Y-type zeolite has extremely less discoloration of the resin and discoloration of the resin over time when kneaded into the resin, as compared with conventional products.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1 (Preparation of Y-type zeolite) 49% sodium hydroxide solution in 850 g of aluminum hydroxide
After 6.2 kg was added and dissolved by heating, the temperature was kept at 35 ° C. or lower (hereinafter referred to as solution I). Colloidal silica (Nissan Chemical Snowtex 3
0) 10.2 kg of water was added to 14.3 kg to dissolve, and the solution temperature was adjusted to 30 ° C. or lower (hereinafter, solution II). The solution I and the solution II were mixed in a reaction kettle while adjusting the solution to 35 ° C or lower.

The obtained mixture (raw material slurry) was stirred at 32 to 35 ° C. for 5 hours (nucleation step). The resulting slurry was then
The mixture was stirred at a temperature of not less than ℃ for 24 hours (crystal growth step). The product was filtered, washed with water, and then dried at 100 ° C.
Got one. The sample was analyzed for chemical composition and particle size. Table 1 shows the results. Table 2 shows the results of the X-ray diffraction test. The X-ray diffraction test data of the Y-type zeolite disclosed in JP-B-54-6519 is also shown as standard data.

Further, Sample No. 2-9 was obtained by changing the composition of the raw slurry and the reaction conditions as shown in Table 1. Table 1 shows the results
Shown in FIG. 1 shows a particle size distribution chart of Sample No. 1.

From the results in Tables 1 and 2, it can be seen that submicron Y-type zeolite was obtained.

Comparative Example Samples Nos. 10 to 14 were obtained by performing the same operation as in Example 1 except that the composition of the raw material slurry and the stirring temperature in the nucleation step and the result growth step were changed. Table 1 shows the raw material slurry composition, reaction conditions and analysis results. Sample No.1
FIG. 2 shows the particle size distribution chart of No. 1.

Example 2 (Preparation of antibacterial zeolite) Sample No. 1 obtained in Example 1 was dried by heating at 110 ° C.
Water was added to 1 kg of this zeolite powder to form a 1.3-liter slurry, which was then degassed by stirring, and further adjusted to a pH of 5-7 by adding an appropriate amount of a 0.5 N nitric acid solution and water, and the total volume was 1.8 l. Slurry. Next, for ion exchange, a mixed solution of 0.03N silver nitrate solution 1, 2.5N zinc nitrate solution 1, and 0.2N ammonium nitrate solution 1 was added to make a total volume of 4.8 l, and the slurry was kept at 40-60 ° C. The mixture was maintained at an equilibrium state with stirring for an hour. After the completion of ion exchange, the zeolite phase was filtered and washed with 4 L of a 0.1 N (specific concentration) aqueous nitric acid solution as an acid treatment. Thereafter, the plate was washed with warm water until excess silver, zinc, ammonium ions and nitrate ions in the zeolite phase disappeared. Next, the sample was dried by heating at 110 ° C. to obtain an antibacterial zeolite powder sample. Ion exchange was performed on the samples No. 11, No. 13 and No. 14 under the same conditions. The content (%) of silver, zinc, and ammonium in the obtained antibacterial zeolite sample was as shown in Table 3 below.

Test Example 1 (Antibacterial activity test) The antibacterial activity was evaluated by the following method.

Test strains include Aspergillus niger (Aapergil
lus niger) IFO 4407 (mold), Candida albicans (Candida albicans) IFO 1594 (yeast), Pseudomonas aeruginosa IID
Five types of P-1 (gram-negative general bacteria), Staphylococcus auresus ATCC 6358P, and Escherichia coli IFO 3301 (all gram-positive general bacteria) were used.

Enrichment medium is for bacteria: Mueller-Hinton Broth (Difc
o), for mold: Potato dextrose agar medium (Eiken), for yeast: Yeast Morphology Agar (Difco). Sensitivity measurement medium for bacteria: Mueller-Hinton Medi
um (Difco) for mold and yeast: Sabouraud agar medium (Eiken) was used.

Preparation of a sensitivity measurement plate was performed as follows. A dilution step suspension of each sample of the antibacterial zeolite obtained in Example 2 was prepared with sterilized purified water, and 1/9 of the medium was added to the medium for sensitivity measurement at 50-60 ° C after dissolution. After sufficient mixing, the mixture was dispensed into a petri dish and solidified to obtain a sensitivity measurement plate.

Preparation of inoculum for bacterial use: For bacteria: Inoculate the enrichment medium with the subcultured test strain, dilute with the enrichment medium so that the number of bacteria becomes 10 ⁶ / ml after culturing, and mix did.

For molds: Inoculate a test strain that has been subcultured into a culture medium for enrichment,
Sterilize the conidia formed after culture to about 10 ⁶ / ml.
% Polysorbate 80 solution to give a bacterial solution for inoculation. For yeast: A test strain subcultured was inoculated into a culture medium for enrichment, and the cells formed after the culture were suspended in sterile physiological saline at a concentration of about 10 ⁶ / ml to obtain an inoculated bacterial solution.

 The culture was performed as follows.

Bacterial solution for inoculation is smeared on a plate for sensitivity measurement with a nichrome wire loop (inner diameter about 1 mm) for about 2 cm.
The mold was cultured for 7 hours at 25 ° C. for 29 hours. The minimum growth inhibitory concentration was determined as the concentration at which growth was inhibited after culturing for a predetermined time.

Table 4 shows the obtained results. Samples No. 1 and No. 14 in which the maximum particle size of the Y-type zeolite is substantially 0.4 μm or less,
It can be seen that the minimum inhibitory concentration for each microorganism is small and the antibacterial activity is strong.

Test Example 2 (Discoloration Test) After the antibacterial aluminosilicate obtained in Example 1 was heated and dried, it was kneaded into a resin (polypropylene: J-109G manufactured by Ube Industries, Ltd.) at a kneading amount of 1 wt%, and this was subjected to injection molding ( Residence time 2
Minutes) to obtain a sample (piece size: 7.3cm x 4.4cm
× 2mm). The obtained sample was irradiated with sunlight outdoors.
The color of each sample is as follows: each sample is white Kent paper (L ^* a ^* b ^* 93.
1, -0.7, -0.5) on the Minolta colorimeter CR-1
It was measured using a Model 00 (using a _D65 light beam). The ratio of L ^* to blank L ^* of the sample represented by the L ^* a ^* b ^* color system according to CIF 1976 was determined, and the results are shown in FIG. The composition ratio of Y-type zeolite (SiO ₂ / Al ₂ O ₃ molar ratio) is 4.0 or more samples N
It can be seen that o.1 and No.13 show less discoloration when kneaded into polypropylene resin than Samples No.11 and No.14 with 4.0 or less.

[Brief description of the drawings]

FIG. 1 is a diagram showing the particle size distribution of the submicron Y-type zeolite of the example of the present invention, and FIG. 2 is a diagram showing the particle size distribution of the Y-type zeolite of the comparative example. FIG. 3 is a drawing showing a change over time of L ^* of a polypropylene resin into which Y-type zeolite has been kneaded.

Claims (6)

(57) [Claims] (1) SiO ₂ / Al ₂ O ₃ (molar ratio) is 4.0 or more,
A submicron Y-type zeolite having a particle diameter of substantially 0.4 μm or less. 2. The method according to claim 1, wherein the SiO ₂ / Al ₂ O ₃ (molar ratio) is at least 4.0 and the particle size is substantially 0.4 μm.
The following method for producing a submicron Y-type zeolite. (A) It contains an aluminum compound, a silicon compound and an alkali metal compound, and SiO ₂ / Al ₂ O ₃ (molar ratio) is 11 to 20, and H ₂ O / Al ₂ O ₃ (molar ratio) is 220 to 300. , M ₂ O / Al ₂
A step of preparing a raw slurry in which O ₃ (molar ratio) (M is an alkali metal) is 6 to 10; (b) a step of maintaining the raw slurry at a temperature of 40 ° C. or lower to generate a zeolite nucleus; (C) a step of growing a zeolite crystal while maintaining the slurry containing the zeolite nucleus at a temperature equal to or higher than the zeolite nucleation temperature. And in wherein SiO ₂ / Al ₂ O ₃ (molar ratio) of 4.0 or more,
An antibacterial zeolite obtained by ion-exchanging part or all of ion-exchangeable metals in a submicron Y-type zeolite having a particle diameter of substantially 0.4 μm or less with antibacterial metal ions. 4. The antibacterial metal ion is silver, copper, zinc, mercury,
The antibacterial zeolite according to claim 3, which is an ion of at least one metal selected from the group consisting of tin, lead, bismuth, cadmium, chromium, and thallium. 5. The SiO ₂ / Al ₂ O ₃ (molar ratio) is not less than 4.0,
An antibacterial zeolite obtained by ion-exchanging part or all of the ion-exchangeable metal in a submicron Y-type zeolite having a particle diameter of substantially 0.4 μm or less with an antibacterial metal ion, and further subject to acid treatment. 6. The antibacterial metal ion is silver, copper, zinc, mercury,
The antibacterial zeolite according to claim 5, which is an ion of at least one metal selected from the group consisting of tin, lead, bismuth, cadmium, chromium, and thallium.