JPH0632826B2 - Method for manufacturing microorganism holding plate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a microorganism holding plate, and more particularly to a method for producing a microorganism holding plate used for biochemical treatment of waste water.

(Prior Art) Conventionally, as a method for producing a microorganism holding plate having a thin film of different components on the surface of a hard vinyl chloride resin sheet (hereinafter referred to as “PVC sheet”), a PVC sheet is molded into a desired shape. After that, in a separate step, the inorganic fine powder is dispersed in a solvent of vinyl chloride to prepare a surface treatment agent,
A method has been adopted in which the PVC sheet formed into the desired shape is dipped in the treatment agent to obtain a microorganism holding plate having a thin film of different components on the surface.

(Problems to be Solved by the Invention) According to the above-mentioned conventional method, (1) it is difficult to uniformly apply the surface treatment agent for a molded product having an uneven surface. (2) When drying the solvent in the surface treatment agent, it is necessary to carry out the drying at a softening temperature of the PVC sheet (60 to 70 ° C.) or lower.
That is, if the temperature is higher than the softening temperature, the shape after molding is likely to be deformed.
(3) There is a problem that the PVC sheet is soaked by the solvent and the physical properties are deteriorated and deformed, and the use of the solvent is not preferable in terms of safety and hygiene, and therefore its use and selection are limited. (4) In addition to the above (1) to (3), there is a problem that the process becomes complicated.

(Means for Solving Problems) In order to solve the above problems, the present invention has the following constituent features.

(1) A step of applying 5 to 500 μm of a composition comprising at least a vinyl chloride resin powder and a plasticizer on the surface of a PVC sheet.

(2) 100 to 2 PVC sheet coated with the above composition
A step of heating at 00 ° C. for 5 to 60 seconds, baking the composition on the surface of a PVC sheet, and forming a film to form a multilayer body.

(3) A method of forming the multilayer body into a desired shape to obtain a microorganism holding plate as a final product.

The rigid PVC used in the present invention contains a general-purpose plasticizer in an amount of about 5 to 1 with respect to 100 parts by weight of a polyvinyl chloride resin obtained mainly by suspension polymerization (hereinafter, “parts by weight” will be referred to as “parts”).
It is blended by adding 0 parts or less.

Further, the composition used in the coating step (1) above has a powdery polyvinyl chloride resin (hereinafter referred to as “PVC powder”) having an average degree of polymerization of 800 to 2,000 and an average particle size of 20 to 60 μ, which is mainly obtained by emulsion polymerization. ) For 100 parts, 30 to 1 of a plasticizer of any one of dioctyl phthalate, dioctyl adipate, tricresyl phosphate, etc.
It is made by adding and blending in the range of 00 parts.

Furthermore, in order to enhance the adhesion activity of microorganisms, one kind of nutrients, microorganisms, enzymes, surfactants, foaming agents, inorganic fillers, etc. is added to the above composition comprising a combination of PVC powder and a plasticizer. Or, two or more kinds may be added in combination.

A stabilizer soluble in a plasticizer is preferably added to the surface modifier in an amount of 0 to 5 to 5 parts with respect to 100 parts of PVC powder.

As the above-mentioned nutritional agent, those which are easily decomposed by microorganisms such as glucose, glutamic acid, sodium acetate, citric acid, etc. to smoothly carry out the metabolic cycle, and which are hardly decomposed near the softening temperature of the PVC sheet are preferably used.

As for microorganisms, enzymes, etc., dry cells such as BOD-oxidizing bacteria, nitrifying bacteria, and methane bacteria should be used in an amount of 0, 1 with respect to 100 parts of PVC powder.
It is used by adding 10 parts. When the amount is 0 or 1 part or less, the activation effect is small, and when the amount is 10 parts or more, the physical properties of the coating film are likely to deteriorate
It is also uneconomical.

As the above-mentioned surfactant, for example, an anionic surfactant or a nonionic surfactant, which is less toxic to microorganisms, is suitable.

Examples of the anionic surfactants include alkyl sodium sulfate, sodium secondary alkyl sulfate, and 2-sulfosuccinic acid dialkylamide. Nonionic surfactants include alkyl polyoxyethylene ether, fatty acid polyhydric alcohol ester, and fatty acid. Polyhydric alcohols such as polyoxyethylene and fatty acid sucrose ester are available. The addition amount is preferably 5 parts or less with respect to 100 parts of PVC powder. If it is 5 parts or more, the physical properties of the coating film are liable to deteriorate and it is uneconomical.

As the foaming agent, among the inorganic foaming agents and the organic foaming agents, a foaming agent that foams at a temperature at which the PVC sheet is softened in the film forming or baking step in the next step is selected, and a foaming auxiliary agent is added as necessary.

The inorganic foaming agent is sodium hydrogen carbonate, azides (calcium azide, etc.), and the organic foaming agent is azo (azobisisobutylnitrile, azodicarbonamide, etc.), hydrazine (diphenylsulfone-3,3'-).
Disulfohydrazine etc.), triazole type, N-
Any nitroso type or the like may be used as long as it satisfies the above foaming conditions.

Further, the inorganic filler is in the form of fine powder such as calcium carbonate, barite, clay and diatomaceous earth, and the addition amount thereof is in the range of 0 to 1 to 20 parts per 100 parts of PVC powder.

Next, as a method of applying the above composition to a PVC sheet, a knife coater, a roll coater, a dipping method, a spraying method or the like is applied so as to obtain a thickness of 5 to 500 μm in a wet state. It is not preferable to set the thickness of the coating film to 5 μm or less because the characteristics of the composition and the equipment cost of the coating process become high, and if it is 500 μm or more, it is uneconomical.

In the step of baking and forming a multilayer body, which is performed after the above step, the PVC sheet coated with the composition is heated to soften the PVC sheet, and a wet coating film is formed and baked.

The heating method employs a hot air forced circulation method or an infrared heater method to uniformly heat the entire surface of the PVC sheet.

The heating is performed by setting the temperature to 100 to 200 ° C. and the time to 5 to 60 seconds, but if the heating temperature is 100 ° C. or less and 5 seconds or less, film formation and baking of the coating film are insufficient, and 200 ° C. or more. Moreover, if it is 60 seconds or more, the PVC sheet is deteriorated by heat and the energy cost is increased, which is not preferable.

The multi-layer body obtained in the above step is molded into a desired shape to obtain a microbial support as a final product.

As the forming method, any one of a vacuum forming method, a pressure forming method, a roll pressing forming method and the like is adopted.

The final shape is shaped into a full-wave corrugated shape and a concavo-convex shape required for the target microorganism support.

In the molding step, the PVC sheet softened in the previous step may be continuously molded, or may be cooled and then reheated to be molded.

Example 1 On the surface of a PVC sheet having a thickness of 0 and 6 mm, an average degree of polymerization of 1,
A mixture composition of 60 parts of dioctyl phthalate, 3 parts of Ca-Zn stabilizer and 2 parts of glutamic acid was prepared with respect to 100 parts of 700 PVC powder, and the composition was applied according to the manufacturing process shown in FIG. Then, baking, film formation, and molding were performed.

That is, in the coating step, PV is added to the tank 2 containing the above composition 3.
C sheet 1 is dipped, composition 3 is attached to both sides of sheet 1, and then the coating film thickness is adjusted to 7 by a coating film thickness adjusting roll 4.
It was adjusted to 0 μ and applied evenly.

The PVC sheet 1 coated with the composition 3 is heated at 130 ° C. by an infrared heater 5 ′ provided in the vacuum forming apparatus 6.
The PVC sheet 1 was softened by heating for 2 seconds, and the coating film in a wet state was baked to form a film, thereby forming a multilayer body.

Next, the softened multilayer body was vacuum-molded by using the concave-convex mold 7 provided in the vacuum molding apparatus 6, and after imparting a concave-convex pattern, it was water-cooled to obtain a microorganism-holding plate 8.

The obtained microorganism holding plate 8 was uniformly formed on both sides of the PVC sheet 1 and strongly baked, and the moldability was also good.

Example 2 A mixed composition of 50 parts of dioctyl phthalate and 3 parts of a Ca-Zn stabilizer on 100 parts of PVC powder having an average degree of polymerization of 1,300 was prepared on the surface of a PVC sheet 1 having a thickness of 0 and 5 mm. Using the surface treatment agent, coating, baking, film formation and molding were performed according to the manufacturing process shown in FIG.

That is, in the coating step, the same treatment as in Example 1 was performed to adjust the thickness of the coating film to 30 μm and apply it uniformly.

The PVC sheet 1 coated with the composition 3 is heated in a heating furnace 5 kept at 150 ° C. for 10 seconds to soften the PVC sheet 1 and at the same time, a wet coating film is baked to form a film. Got

Then, the softened multilayer body was passed between the pressing rolls 7'of the concavo-convex patterning device to form a corrugated plate, and then air-cooled to obtain a microorganism holding plate 8.

The obtained microorganism holding plate 8 had composition layers evenly formed on both sides of the PVC sheet 1, and was strongly baked, and had good moldability.

(Effects of the Invention) The method for producing a microbial support plate according to the present invention is the same as the conventional PVC.
Compared with the method of treating the surface of the sheet to form a thin film composed of different components, the following effects are obtained.

(1) A thin film of the composition is evenly formed on both surfaces of the microorganism retaining plate having irregularities.

(2) Since the PVC sheet having the coating film layer formed thereon is heated and the coating film in a wet state is baked to form a film, it does not peel off even when firmly attached and molded.

(3) Since no solvent is used for forming the coating film, the physical properties of the PVC sheet are not deteriorated or deformed.

(4) Since no solvent is used, there is no danger of ignition and it is safe.

(5) The manufacturing process is simple and can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a manufacturing process of an embodiment of the present invention, and FIG. 2 is an explanatory view showing a manufacturing process of another embodiment. 1 ... PVC sheet, 2 ... tank, 3 ... composition, 4 ...
Coating film thickness adjusting roll, 5 ... Heating furnace, 5 '... Infrared heater, 6 ... Vacuum forming device, 7.7' ... Concavo-convex patterning device, 8 ... Microorganism holding plate

Continuation of the front page (56) Reference JP-A-53-35247 (JP, A) JP-A-59-382 (JP, A) JP-A-55-111895 (JP, A)

Claims (1)

[Claims] 1. A surface of a hard vinyl chloride resin sheet material,
A composition comprising at least vinyl chloride resin powder and a plasticizer is applied in an amount of 5 to 500 μm, and then 5 to 6 at 100 to 200 ° C.
A method for producing a microorganism-holding plate, comprising heating the composition for 0 seconds, baking the composition on the surface of a sheet to form a multilayer, and molding the multilayer into a desired shape.