JPH01101360A - Binder for bonding inorganic fiber - Google Patents

Abstract

PURPOSE:To obtain a binder having excellent moisture resistance and giving a colorless or slightly colored cured article, by compounding a water-base melamine resin with an ethylene oxide adduct of a novolak resin. CONSTITUTION:(A) A water-based melamine resin containing methylol group and/or alkylated methylol group is compounded with (B) a compound of formula (l, m, n and p are integer of >=0; average of l, m and n is >=3). The average of l, m and n is preferably 4-6 and the value of p is preferably 2-6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a binder for binding inorganic fibers, and particularly to a binder for binding inorganic fibers that has excellent moisture resistance and hardens to a colorless or light color.

[Prior art and its problems] When processing inorganic fibers such as glass fibers and rock wool into pine shapes to produce heat insulating materials, sound absorbing materials, etc., a binder is used to bind the inorganic fibers. Generally used are binders based on phenolic resins or urea-phenolic resins. Although these have strong mechanical bonding strength and fairly good heat resistance and moisture resistance, they have the disadvantage that they turn reddish brown or yellowish brown in color when hardened.

Therefore, mats using these binders are suitable for use in houses, etc.
8 There is no problem when used inside a structure, but for example, when used as a ceiling material, there are problems such as uneven coloring and reduced illumination resistance.

Therefore, a binder that hardens to a colorless (white) or light color is required, and binders whose main components are various latexes such as vinyl acetate resin emulsion and styrene-butadiene co-compounds, melamine resin, urea resin, etc. are being applied. Although attempts have been made to do so, the moisture resistance and heat resistance of all of them are inferior to binders whose main component is phenolic resin, and mats processed using them often have problems when used in humid locations for long periods of time. .

The present invention was made in view of the above-mentioned state of the prior art, and an object of the present invention is to provide a water-based binder for fiber-free bonding that is colorless or light-colored and provides a cured product with strong bonding strength. .

[Means for Solving the Problems] As a result of 81 intensive investigations, the present inventors found that an aqueous melamine resin containing a methylol group and/or an alkylated methylol group and a compound represented by the following general formula (A) (Hereinafter referred to as compound (A)) It was discovered that the above object could be achieved by applying a binder for binding inorganic fibers containing as an essential component, and the present invention was completed.

(In the formula, z, m, n and p each represent an integer of 0 or more, and!, the average of all ml and n is 3 or more) Containing a methylol group and/or an alkylated methylol group in the present invention The water-based melamine resin refers to a water-based melamine resin having a structure in which a methylol group and/or an alkylated methylol group are bonded to melamine.
It may also contain a dimethylene ether group or a methylene group. The melamine resin is ILL'ed by reacting melamine with formaldehyde under an alkaline catalyst or by subsequent treatment with an aliphatic alcohol under acidic conditions. The alkyl group of the alkylated methylol group is not particularly limited, but a methyl group is most suitable. The aqueous melamine resin may also be modified with urea, phenol, benzoguanamine, dicyandiamide, etc. or derivatives thereof. Furthermore, the term "aqueous" as used herein means that the resin is not only an aqueous solution, but also that the resin component is appropriately suspended or dispersed in water so that the entire resin can be treated as an aqueous liquid.

The compound (^) in the present invention can be produced, for example, by adding ethylene oxide to a novolak resin under an alkaline catalyst. In the formula representing compound (A)! ,
All m and n do not have to be equal to each other, but the average of all 11 m and n needs to be 3 or more. If it is less than 3, the solubility of compound (A) in water is insufficient. For example, glass mats are processed by blowing molten glass into lli fibers, then spraying a binder onto it to form it, so it is essential that the binder is water-based from the standpoint of safety and performance. . m in all 11
, n is preferably 4 to 6 on average from the viewpoint of the balance between solubility in water and moisture-resistant bond strength, but this balance differs slightly depending on p. On the other hand, p may have a distribution, but it is preferable for the average p to be in the range of 2 to 6.

The blending ratio of the melamine resin containing a methylol group/or an alkylated methylol group and the compound (A) is based on the equivalent amount of the sum of the methylol groups and the alkylated methylol groups in the melamine resin to the hydroxyl group in the compound (A). Considering the properties of the cured product, it is appropriate to increase the amount. However, since the optimum conditions vary depending on the structure of the melamine resin, the hydroxyl value of compound (A), and the curing conditions, it is not possible to specify the optimum blending ratio in detail. In addition, if the melamine resin is too excessive, too much crosslinking will occur between the melamine resins, making the cured product too hard and the moisture-resistant bonding strength will also decrease.On the other hand, if the compound (A) is in excess, the cured product will become too hard. becomes too soft and unreacted water IB in compound (A)
Since a large amount of remains, the moisture-resistant bond strength also decreases.

Now, one of the key points of the present invention is that the melamine resin containing a methylol group and/or an alkylated methylol group and the compound (^) react and harden to produce a binder effect, but this reaction is not sufficient to be carried out by heating alone. Because it is difficult to proceed, it is necessary to add a reaction catalyst to the binder at the same time. For example, an acid can be used as a catalyst, but if the acid is blended directly, problems with the storage life of the binder and container corrosion are likely to occur.
Alternatively, it is industrially advantageous to use a substance that can be thermally decomposed to produce an acid. Such substances include
Salts of acids such as sulfuric acid, boric acid, hydrochloric acid, phosphoric acid, para-toluenesulfonic acid with ammonia or amines such as mono-, di- and trialkylamines, mono-, di- and trialkanolamines, aromatic amines are preferred, e.g. Examples include ammonium sulfate, ammonium chloride, jetanolamine sulfate, jetanolamine hydrochloride, triethanolamine hydrochloride, 2-amino-2-methyl-1-propanolamine hydrochloride, diethylamine phosphate, diethylamine hydrochloride, etc. . In addition, carboxylic acid esters such as dimethyl oxalate, organic halides such as monochloroacetic acid sodium salt, metal chlorides such as magnesium chloride, etc. can also be blended into the binder of the present invention and used as catalysts.

Further, in addition to the above-mentioned main components, a coupling agent such as an aminosilane compound for increasing the bonding strength, a dye or a pigment for coloring, etc. can also be blended into the binder of the third invention.

[Effects of the Invention] When the binder according to the present invention is used as a binder for matting inorganic fibers such as glass fibers and rock wool, it is possible to mold pine 1~ which is white or light in color and has good normal strength and moisture resistance strength. Not only can it be used as an excellent heat insulating material or sound absorbing material, but it can also be used as a sizing agent for inorganic fibers.

[Example] Next, the present invention will be explained by giving synthesis examples and application examples.

All parts and percentages shown below are based on weight.

Melt 100 parts of "Whale Blood" [Gokai novolac resin (manufactured by Dainippon Ink & Chemicals Co., Ltd., Barkham TD-2131] in an ormil crepe, add 015 parts of potassium hydroxide, and add N
In an atmosphere of two gases, 130 parts of ethylene oxide were introduced at 5° C. and 215 parts of ethylene oxide at a maximum pressure of 7 atm while maintaining the temperature at 5 to 7 atm. After ethylene oxide is reacted and consumed,
pl+ of the aqueous solution of the product using an appropriate amount of 5% phosphoric acid aqueous solution.
The mixture was neutralized to a value of about 7, and then 11 g or less of 50 mm was subjected to simple distillation under reduced pressure at 180° C. to remove water, yielding 310 parts of compound (A-1).

Compound (A-1) is a pale yellow liquid and was confirmed by NMR to have the structure of compound (^), with a valence of 08 and 174m! IIK011/(1, viscosity (25℃) 323
It was 0 cPs.

Synthesis of melamine resin containing methylol group Melamine 126
260 parts of 37% formalin were charged into a reaction vessel.
Add sodium carbonate little by little and change the reaction system I) 11 to 10
Adjusted to. Then, the temperature was raised to 80℃ by rapid heating, and the temperature was increased to 80℃.
The mixture was kept at ℃ for 4 hours to obtain 386 parts of methylol group-containing melamine resin (B) with a non-volatile content of 57%.

Example 1 70 parts of the compound (A-1) produced in the above synthesis example, 30 parts of Beckamine APH (commercial product manufactured by Dainippon Ink and Chemicals Co., Ltd.: methylated methylol group-containing melamine resin) (10 parts of methylated methylol group) [1 group equivalent ratio of about 1.0)] and 0.3 part of jetanolamine hydrochloride were used to prepare a resin liquid and subjected to the following applied test.

Example 2 A resin liquid was prepared in the same manner as in Example 1, except that 50 parts of compound (A-1) and 50 parts of Beckamine^PH (methylated methylol group 1011 equivalent ratio of about 2.3) were used. It was subjected to the following applied test.

Example 3 30 parts of compound (A-1) and 70 parts of Beckamine APH (methylated medirol, 110111u equivalent ratio of about 5.5
) A resin liquid was prepared in the same manner as in Example 1, except that
It was subjected to the following applied test.

Example 4 40 parts of compound (^-1), 60 parts of methylol group-containing melamine resin (B) (methylol group 10H group suspension ratio approximately 1.
3) A resin liquid was prepared using 0.3 part of rice jetanolamine hydrochloride and subjected to the following applied test.

Comparative Examples 1 to 4 As a resin liquid (respectively, urea-modified phenolic resin Pryophen IQ-6388 (Dainippon Ink & Chemicals Co., Ltd.)
Co., Ltd. (commercial product) (Comparative Example 1), phenolic resin Pryophen TO-2350-60 (commercial product available from Dainippon Ink & Chemicals Co., Ltd.) (Comparative Example 2), urea resin Plyamine J-402 (Dainippon Ink & Chemicals Co., Ltd.) (Comparative Example 2) (Commercial product manufactured by Nippon Ink Chemical Industry Co., Ltd.) (Comparative Example 3) A mixture of Onibi Beckamine Shizuo OO part and Jetanolamine Hydrochloride 1 part (Comparative Example 4) was used as a comparative example for the following applications. Tested.

Applied test 10 parts of short glass tIa fibers were evenly spread on a wire mesh, and 50 parts of each resin solution diluted with water to have a non-volatile content of 2% was added.
The expanded glass strip was sprayed on both sides of the surface and allowed to dry at room temperature for 30 minutes. After that, this short glass fiber sheet was cut into a 10 cm x 80 cm sheet, which was folded into 6 pieces, each 10 cm x 10 cm, to make 9 of the same size, and stacked so that the folded and cut surfaces alternated. Combined. The short glass fiber pine 1~ produced in this way has a bottom surface of 100 m x 10 cuts and a height of 2
．． It was placed in a 5 part m metal frame, covered with wire gauze on both sides, and hardened in a forced circulation electric furnace at 200°C for 3 minutes. The hue of the completed mat was measured by vA, and then the peel strength was measured. Peel strength was measured by attaching Kinku Yako to the top and bottom of the mat with adhesive and pulling it in the thickness direction until the mat peeled off.
The maximum load J was determined. The mats were placed in a drying desiccator immediately after mat production, and the humidity resistance strength was measured using mats that were placed in an atmosphere at room temperature and relative humidity of 90% for one week (13 days) immediately after mat production. The results are shown in Table 1. As shown in Table 1, the mat of the present invention was the only one that was white and had good normal strength and moisture resistance.

(Margin below)

Claims (1)

[Claims] (1) Water-based melamine resin containing a methylol group and/or alkylated methylol group and the following general formula (A)
A binder for binding inorganic fibers, comprising a compound represented by the following as an essential component. ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(A) (In the formula, l, m, n, and p each represent an integer of 0 or more, and the average of l, all m, and n is 3 or more. )