KR960014562B1 - Process for producing rock wool ceiling panel having good water resistance and moisture proofness - Google Patents

Abstract

This invention relates to the roof plate having wate rproof and moisture-proof property and the method of manufacturing the roof plate including the steps of mixing rock wool(40-90), filler(0-30), pulp(0-15), starch(2-10) and inorganic coupler(2-30) in the ratio of weight percent to be a slurry of 2-5 %; producing a plate by putting acryl denatured epoxy resin(0.1-2.0) in that slurry; and drying and sequentially curing the result at 160-250 deg.C.

Description

Manufacturing method of rockwool ceiling plate with excellent water resistance and moisture resistance

The present invention provides moisture resistance and water resistance to the ceiling plate by using a resin composition for rock wool ceiling plates having high moisture resistance among the interior materials of buildings, and due to surface condensation and sagging due to color change and moisture absorption of the paint surface due to water pipe leakage (SAG) It relates to a method of manufacturing a rock wool ceiling plate to prevent the phenomenon.

Absorption of moisture in the hot and humid rainy season or in places where a large amount of moisture occurs in summer results in color change and sagging of the painted surface of the paint, resulting in deterioration of the appearance and properties of the rock wool ceiling. Therefore, it has been required to prevent sagging of the ceiling plate.

Accordingly, an object of the present invention is to minimize the deflection of the ceiling plate by solving the above problems.

In general, the wet method is used to form inorganic plates (rock wool), organic fibers (pulp), inorganic fillers, organic binders, starches, etc., and these are slurried to form a wet plate. Rock-fiber ceilings were prepared by surface grinding, surface coating and patterning, but water repellents and other raw materials were sometimes added during the mixing process.

In addition, starch used as a binder can be molded by adding luxury starch, and raw starch can be heated before being dried by drying in the drying process to make rock wool top plate, and the input ratio of starch is about 4-15%. to be.

In the general method as described above, the rock wool ceiling plate integrated by starch at a size of about 2 × 4 is a ceiling material, and when exposed to the air and hanged, the central part of the plate becomes convex. This deflection phenomenon causes starch used as a binder to bind and exist as a thin film or agglomerate at the intersection point between the fibers, which is caused by the deterioration of the binding force due to the wetness of the starch binder.

The property of the above is that the more the surface of the rockwool absorbs moisture, the central part of the ceiling plate sags due to the deterioration of the function of the starch binder.

There are three ways to improve the deflection phenomenon, one of which is to apply a resin compound on the surface of the plate, the other is to attach a reinforcing rod on the back of the plate, and finally There is an internal treatment method in which special additives are added.

In US Patent Publication No. 3146156, one or two or more resin composites of water, moisture, and thermosetting resins may be applied to the back surface of the plate and cured to prevent sagging during ceiling construction. However, this is necessary when grinding the back surface of the plate. In Japanese Laid-Open Patent Publication No. 86-40946, the super-molding method of laminating the upper and lower layers is 0.1-0.2% when the upper layer temperature is 30 ° C. and the humidity is 50-90% RH. The lower layer has a linear expansion rate of 0.04-0.007% under the same conditions, so that the upper layer has a larger linear expansion rate when absorbed than the lower layer, thereby preventing sagging.

However, in general, the method of coating the resin composite or laminating the two-layer lamination by the difference in the linear expansion rate can be prevented to some extent, but the manufacturing technique of the uniform resin composite, the amount of coating and the constant of the linear expansion rate are limited. Therefore, depending on the conditions, the phenomenon of concave upward occurs as opposed to the deflection downward. Accordingly, when viewed from the place where the ceiling plate is constructed, the uneven wave phenomenon of concave-convexity is found continuously as the ceiling plate is sheeted, which is also a fatal defect for the ceiling plate. In addition, when using aluminum or tin structure as a deflection reinforcement reinforcement, it is very helpful to prevent the deflection phenomenon, but the construction of the ceiling plate should be installed on the surface layer at the same time. Water repellent should be added to raw material process in order to prevent the color change of the painted surface by water permeation due to the phenomenon.

This method is also described in U.S. Patent Nos. 3243340, 444594 and 3146156, but this may be partly helpful in preventing sagging of the ceiling plate but may be limited in scope and uneconomical.

As a patent related to rockwool ceiling plates with improved moisture resistance, Japanese Patent Publication Nos. 8727570, 87128978, 8778139, or 8692249 use acrylic binders such as hot water-soluble starch to form acrylic on one or both sides after plate forming. -Moisture-proof effect is obtained by using 2-25% of styrene resin, petroleum resin or one or more resins of rosin resin. This also has the drawback that the excessive use of organic materials inhibits the flame resistance of the product.

In Japanese Patent Publication No. 85246899, it is possible to achieve moisture resistance and high strength by using 8-15% of various raw materials and cationic melamine resins. However, excessive use of organic material melamine releases harmful gases in case of fire.

In Japanese Patent Publication No. 85246899, 3-10% of PVA is used, and PVA alone has a strength retention ratio of 30% of its normal state when absorbed, so that the use of a relatively high humidity environment is insufficient, so that urea resins, melamine resins, 3% or more of alkali hardening type ketonealdehyde resin, epoxy crab polyamide, formaldehyde resin, metal salts such as chromium, antimony and zirconium, heavy metal salts such as zirconium carbonate and zirconium acetate as solids with respect to PVA It imparts moisture resistance by injecting, but it is uneconomical due to the high price of raw materials.

In Japanese Patent No. 7722026, there have been many problems with the deflection prevention technology of rockwool ceiling plates in the same context.

Accordingly, an object of the present invention is to solve the conventional problems, and to provide a method for producing a rock wool ceiling plate simply and economically by using a resin composition for rock wool ceiling plate having a strong moisture resistance.

The method for preparing a rockwool ceiling plate according to the present invention is based on the weight percent rock wool 40.0% -90.0%, pulp 0.0-15.0%, filler 0.0-30.0%, starch 2.0-10.0%, and inorganic binder 2.0-30.0% 2 It is made of -5% slurry, and 0.1-2.0% of water-dispersible acrylic modified epoxy resin composition is added thereto to prepare a wet plate, which is dried and cured at 160-250 ° C.

The water dispersible modified epoxy resin used in the method of the present invention is an epoxy resin or a derivative thereof and polyacrylamide as a main component, and is a water dispersible epoxy resin made by reacting a curing agent to agglomerate particles of an inorganic filler during molding of a blended raw material. It adheres between fibers to improve dehydration ability, and the sucker reacts with functional groups of epoxy resin and polyacrylamide when heated and dried in a dryer to form a three-dimensional network structure to form a water-insoluble polymer membrane. The reaction also exhibits excellent agglomeration, water resistance and moisture resistance to prevent sagging of the ceiling plate.

Hereinafter, the resin composition used in the method of the present invention will be described in detail.

General formula of the epoxy resin used in the present invention is as follows.

Epoxy resins contain two or more epoxy groups per molecule The most typical epoxy resin is bisphenol A / epichlorohydrin type and diepoxide having an epoxy group at both ends of the molecular chain. That is, when glycidyl ether of bisphenol A and other raw materials are used instead of bisphenol A, various glycidyl compounds are epoxy resins, and n represented by the above formula is generally used in the range of n = 0.1-16.00. In particular, in the present invention, n = 0.1-0.3 is suitable, epoxy equivalent is 180-220, transparent liquid resin, viscosity at 250 ° C is about 1000-1500CPS, specific gravity is about 1.05-1.20. However, the epoxy resin used industrially is not water-soluble, so it cannot be used as it is in the manufacturing process of rock wool ceiling plates, and should be used after making it water-soluble.

In general, the water-insoluble epoxy resin is made water-soluble using an emulsifier, but in the present invention, polyacrylamide, which is a polymer flocculant used in the manufacture of rockwool ceiling plates without using an emulsifier, is used. The epoxy resin is cured in the presence of the amine group (-NH ₂ ), so that it can be solubilized and cured by the reaction of polyacrylamide used as a flocculant.

Polyacrylamide, a polymer coagulant, is polymerized by polymerization of basic composition, and classified into nonionic, cation, and anion depending on ionicity in aqueous solution. The basic composition is as follows.

The first amine (RNH ₂ ) and the second amine (R ₂ NH) are widely used as curing agents for epoxy resins. In theory, one RNH ₂ molecule reacts with two epoxy groups to form a crosslink. For example, the polyvalent first amine is ethylenediamine (H ₂ N-CH ₂ -CH ₂ -NH ₂ ) or diethyltriamine (H ₂ N-CH ₂ -CH ₂ -NH-CH ₂ -CH _2- NH ₂ ) reacts with four and five epoxy groups, respectively. That is, the total number of hydrogen atoms bonded to the nitrogen atom is the reaction water other than the epoxy group. All three types of ionic properties of the polymer coagulant can be used, and the epoxy resin and the polymer coagulant are cross-linked with the epoxy group and the primary amine group of the polymer coagulant to solubilize as follows.

The RNH ₂ group in the polymer flocculant first reacts with one epoxy group

The first amine becomes a second amine, and the second amine reacts with another epoxy group

As described above, since the second amine becomes a third amine and is assembled in the epoxy resin molecule to crosslink two epoxy resin molecules, polyacrylamide, which must be added in the manufacture of rockwool ceiling plates, acts as a curing agent for epoxy resin. At the same time, water solubility, cohesiveness, and water resistance and moisture resistance by curing after drying are given. Epoxy resin must be cured, and in curing, it can be classified into room temperature curing type (mainly 2 liquid type) and high temperature curing type (heat curing type: 1 liquid type). In room temperature curing type, pot life (POT LIFE) is short and rock wool It is difficult to be applied to the ceiling plate process and only suitable for high temperature curing type, and the epoxy resin and polyacrylamide in the present invention satisfies these conditions well, and the resin composition maintains stability during the pot life of about 6 months at room temperature. have.

Also in the solubilization and hardening reaction of the above-mentioned epoxy resin and polyacrylamide, these compounding ratio is very important.

In the present invention, since the average molecular weight of the epoxy resin used is about 360 and the molecular weight of the polyacrylamide monomer is 71, the theoretical equivalent compounding ratio for curing is epoxy resin (360): polyacrylamide (71) = 5: 1 It is about.

However, as described above, the theoretical equivalent composition ratio of the resin and the curing agent is that the width of the input amount during the blending of the polyacrylamide, which is a polymer coagulant, decreases, so that the width of the resin mixture in the ceiling plate is simultaneously reduced.

Therefore, in order to widen the range of dose changes, it is necessary to be able to sufficiently cure the compounding of a small amount of polyacrylamide. As described above, since the pot life is not applicable to the room temperature hardener, a latent curing agent (heat curing type) must be used in the present invention.

Epoxy resins are also cured by complexing Lewis acids with amines. In particular, amine salts and boron trifluoride-amine complexes are useful as heat curing agents. The mechanism of this curing reaction is that the Lewis acid complex compound dissociates at a certain temperature, and the recovered Lewis acid acts as a catalyst for the polymerization of the epoxy resin.

Representative of these complexes of Lewis acids and amines are boron trifluoride-amine complexes, and BF ₃ -aliphatic primary amines and secondary amines are typical latent curing agents, and the structure of BF ₃ monoethylamine (BF ₃ · MEA) is As follows.

Their reactants have a long pot life of about 6 months at room temperature. Since the BF ₃ -amine agent is a catalytic curing agent, the compounding amount is possible in a small amount of 0.5-4% by weight relative to the epoxy resin, and the resin is heated to about 70-90 ° C., and the BF ₃ MEA is dissolved and cooled in the target product. It is possible to manufacture and postcure at a certain temperature during heating and drying of rockwool ceiling plates. As another latent curing agent, dicyandiamide (cyanguanidine) or a derivative thereof may have the following structural formula.

In addition to the reaction of the four active hydrogens and the epoxy group, this may be a polymerization catalyst or react with the CN group and the epoxy group. For this reason, the compounding amount is about 11% by weight of the liquid diglycidyl ether bisphenol A calculated from the active hydrogen, but is preferably 4-10% by weight, and the resin is well cured with the organopolyamine. do. Dicyandiamide derivatives are synthesized from dicyandiamide and aromatic amines as guanidine compounds of the following structure.

These guanidine compounds can be used because they are completely compatible with epoxy resins, chemically homogeneous, have lower reaction temperatures and relatively longer gel times than dicyandiamide. When the acrylic modified epoxy resin composition is added to the raw material solution of the present invention by about 0.1-2.0% to form a wet plate and dry harden, the rockwool ceiling plate after processing exhibits excellent water resistance and moisture resistance and also improves the deflection phenomenon, which is the subject of the present invention. You can do it.

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

Example 1

100 parts by weight of epoxy resin was placed in a four-necked flask, and when heated to about 55 ° C., 10 parts by weight of anionic polyacrylamide was added thereto, and the reaction mixture was allowed to react for about 2 hours at a speed of about 500 rpm.

As a result, a water dispersible epoxy resin composition was prepared, and when the temperature was increased, the reactivity with the polyacrylamide was improved due to the viscosity decrease of the epoxy resin, and the water dispersibility and cohesiveness were easy. At this time, if the temperature exceeds 90 ℃ it will be a rapid curing reaction to give a gel-like resin composition should be careful. This epoxy resin composition was reacted as follows to prepare a latent resin composition (A).

Example 2

5 parts by weight of anionic polyacrylamide was added to 100 parts by weight of epoxy resin, and the reaction rate was lowered to about 300 rpm. After the reaction, the mixture was adjusted to 50% concentration by slowly adding cold water and stirred for about 10 minutes, and then 10 parts by weight of dicyandiamide, a viscous curing agent, was added thereto. Cold water was added thereto so that the total solid content was 10%, and the mixture was stirred and reacted for about 1 hour. As a result, a water dispersible epoxy resin composition (B) was prepared.

Example 3

5 parts by weight of anionic polyacrylamide was added to 100 parts by weight of epoxy resin, and the reaction rate was lowered to about 300 rpm. After the reaction, cold water was slowly added to the 50% concentration and stirred for about 10 minutes, and then 3 parts by weight of boron trifluoride monoethylamine (BF ₃ · MEA) as a latent curing agent was added thereto. Cold water was added thereto to make the total solid content 10%, followed by stirring and reacting for about 1 hour.

As a result, a water dispersible epoxy resin composition (C) was prepared.

Example 4

5 parts by weight of cationic polyacrylamide was added to 100 parts by weight of epoxy resin, and the reaction rate was lowered to about 300 rpm. After the reaction, cold water was slowly added to the 50% concentration and stirred for about 10 minutes, and then 3 parts by weight of boron trifluoride monoethylamine (BF ₃ · MEA) as a latent curing agent was added thereto. Cold water was added thereto so that the total solid content was 10%, and the mixture was stirred and reacted for about 1 hour. As a result, a water dispersible epoxy resin composition (D) was prepared.

Example 5

40 parts by weight of a general silicone oil was added to 100 parts by weight of an epoxy resin and reacted at a temperature of 50 ° C. for about 1 hour to form a silicone-modified composition (E) having the following structure.

(R, R 'is an alkyl group)

20 parts by weight of polyacrylamide was added to 100 parts by weight of the resin composition to react for about 2 hours.

The physical properties of the rockwool ceiling plate obtained by adding 0.1-2.0% of the epoxy resin composition of Examples 1 to 5 to the solid content concentration of the slurry for the rockwool ceiling plate, and drying and curing the wet plate, are shown in Table 1 below.

It is not limited to the blending ratio in the above embodiment, the resin composition may be added in various amounts up to 0.1-2.0%, and rock wool or clay and other components may be variously changed. As can be seen in the above embodiment, it was confirmed that the improvement of physical properties can be achieved in comparison with the sag phenomena due to the internal treatment of silicon oil or application of the back surface of the resin composition.

Moreover, generally, the construction size of rockwool ceiling plates is 2 '× 2' or 2 '× 4', and the width to length ratio is about 1: 1-1: 1, and the experimental conditions are 32.2 ° C and 90% RH. The specimen in the above embodiment has a width: length ratio of more than 1: 9 and is due to double-sided draping in the width direction.

Comparative Example 1

The mixing ratio of the general wet rock top plate is shown.

Comparative Example 2

The sagging phenomenon was observed by adding silicone oil as a water repellent agent in the mixing ratio of the general wet rock wool ceiling.

Comparative Example 3

The deflection phenomenon was measured by applying the resin solution as an external treatment on the back of the mixing ratio of the general wet front ceiling plate.

Comparative Example 4

8 parts by weight of polypropylene glycol (PPG) was added as an emulsifier to 100 parts by weight of epoxy resin (equivalent 180), followed by stirring at a stirring speed of 2500 to 3000 rpm for about 3 minutes.

Here, 60 parts by weight of polyamide (P.A. equivalent 115) was added as a curing agent, and the mixture was reacted at room temperature for about 10 minutes, 172 g of water was added, and stirred for about 3 minutes to form a high viscosity epoxy resin composition. Adding an appropriate amount of water to the concentration to be suitable for use to obtain a water-dispersible resin composition. 0.2% of such a resin composition was added to the solid component as an alternating component, aggregated, dried, and cured.

The above results are obtained by measuring the relative comparison after maintaining the relative humidity at 95% and the temperature of 60.0 ° C for 24 hours, and the specimen size is 14T × 35W × 350L (span length is 328mm).

The resin composition is treated in the pot life because the pot life is maintained for 1-3 hours depending on the amount of polyamide used. As can be seen in Comparative Examples 1-4, it can be seen that the sagging phenomenon of silicone oil is not prevented as a general water repellent. In Comparative Example 4, the epoxy resin composition was measured but the water resistance and sagging are extremely good. However, the pot life of this resin composition is short, it can be seen that industrially difficult to apply to rock wool ceiling products.

Claims (1)

A slurry of 40-90% rock wool, 0-30% filler, 0-15% pulp, 2-10% starch, and 2-30% inorganic binder, based on weight percent, is added to the water-dispersible acrylic A method for producing a rockwool ceiling plate having excellent water resistance and moisture resistance, characterized by preparing a wet plate by adding 0.1-2.0% of a modified epoxy resin composition, and drying and curing it at 160-250 ° C.