JPH09170151A - Binder for nonwoven fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a binder for a nonwoven fabric, comprising an aqueous emulsion, a thermosetting amino resin and an aqueous solution of an acrylamide- based polymer, capable of suppressing the deterioration of tensile strength while hot, increasing the tensile strength and tear strength in an ordinary state, excellent in flexibility and useful for waterproofing, etc., of buildings. SOLUTION: This binder for a nonwoven fabric comprises (A) an aqueous emulsion, prepared by carrying out the emulsion copolymerization of 1-30 pts.wt. ethylenically unsaturated monomer containing amide group (e.g. acrylamide) with 99-70wt.% other ethylenically unsaturated monomers such as methyl acrylate and having 50-90 deg.C glass transition temperature, (B) a thermosetting amino resin such as a urea resin and (C) an aqueous solution of an acrylamide- based polymer. The blending ratio of the components (A), (B) and (C) is respectively preferably within the range of (3-96)/(96-3)/(1-10) pts.wt. based on 100 pts.wt. sum total of the solid content of the components (A), (B) and (C).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-woven fabric binder, and more particularly to a non-woven fabric binder for imparting excellent hot tensile strength to a non-woven fabric for asphalt impregnation used for building waterproofing.

[0002]

2. Description of the Related Art Asphalt-impregnated non-woven fabrics, which are currently mainly used for waterproofing buildings, are obtained by impregnating a sheet-like web of various fibers with a binder and then heat-treating it.
It is produced by imparting normal tensile strength, normal tear resistance, normal flexibility, and hot tensile strength to a nonwoven fabric, and further impregnating this nonwoven fabric with asphalt melted at high temperature.

As described above, since the non-woven fabric is impregnated with the asphalt melted at a high temperature, one of the most important performances required for the non-woven fabric before the asphalt impregnation is the hot tensile strength. Therefore, a thermosetting resin has been used as a binder, in particular, as a means for imparting a tensile strength when heated.

[0004]

However, since it alone lacks flexibility in the normal state and heat, it has been attempted to add flexibility by using an aqueous emulsion together.
Instead, the adverse effect that the tensile strength at the time of heat lowers occurs. In view of such circumstances, the present inventors have previously used, in Japanese Patent Application No. 05-013264, a specific aqueous emulsion and a thermosetting amino resin in combination as a binder for a non-woven fabric whose tensile strength at the time of heating does not decrease. I'm making a proposal.
Although it was able to extremely suppress the decrease in tensile strength under heat, the normal tensile strength and the normal tear resistance were not always satisfactory, and overall it was still insufficient. Therefore, in the industry, it is desired to develop a comprehensively excellent binder as a non-woven fabric binder.

[0005]

Means for Solving the Problems The inventors of the present invention have made earnest studies in view of the above-mentioned circumstances, and as a result, have found that a conventional thermosetting amino resin and an aqueous emulsion are used in combination and an acrylamide polymer aqueous solution is further used. By mixing at a constant ratio, a comprehensively balanced binder composition for a non-woven fabric was found, and the present invention was completed.

That is, the present invention provides a nonwoven fabric binder comprising an aqueous emulsion (A), a thermosetting amino resin (B) and an aqueous solution of an acrylamide polymer (C).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The aqueous emulsion (A) used in the present invention is obtained by a known emulsion polymerization method in which an ethylenically unsaturated monomer containing an amide group and another ethylenically unsaturated monomer copolymerizable therewith are shown below. Obtainable.

The ethylenically unsaturated monomer containing an amide group is preferably added in an amount of 1 to 30% by weight, and the other ethylenically unsaturated monomer copolymerizable therewith is 99 to 70% by weight. It is preferred to add wt%. Obtained by emulsion polymerization of these, and glass transition temperature (Tg)
Is preferably an aqueous emulsion having a temperature of 50 to 90 ° C.

The aqueous emulsion (A) can be obtained by the following known emulsion polymerization method. That is, to a suitable amount of water with a small amount of an emulsifier and a polymerization initiator added, a mixed solution of an ethylenic unsaturated monomer containing an amide group described later and another ethylenically unsaturated monomer is dropped, The unsaturated monomer is emulsion polymerized.

Examples of the amide group-containing ethylenically unsaturated monomer used in the present invention include acrylamide, methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, and N-methylol crotonamide. One kind or two or more kinds of is used. Of these, methacrylamide is preferably used.

Other ethylenically unsaturated monomers copolymerizable with the amide group-containing ethylenically unsaturated monomer used in the present invention include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate and propyl. Acrylic alkyl esters and methacrylic acid alkyl esters exemplified by acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, pentyl acrylate, pentyl methacrylate and the like; ethylenic exemplified by styrene, α-methylstyrene, vinyltoluene, chlorostyrene, etc. Unsaturated aromatic monomers; vinyl esters such as vinyl acetate and vinyl propionate; ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid and their anhydrides; Ethylenically unsaturated dicarboxylic acids such as acid and itaconic acid; Hydroxyalkyl esters of ethylenically unsaturated carboxylic acids such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate and 2-hydroxyethyl methacrylate; glycidyl acrylate and glycidyl methacrylate Examples thereof include glycidyl esters of ethylenically unsaturated carboxylic acids; nitriles such as acrylonitrile and methacrylonitrile, and one or more of these are used.

The ratio of the total amount of the above-mentioned ethylenically unsaturated monomers containing an amide group to the total amount of the other ethylenically unsaturated monomers copolymerizable therewith is 1
-30: 99-70% by weight is preferable. When the amount of the ethylenically unsaturated monomer containing an amide group is less than 1% by weight and the amount of the other copolymerizable ethylenically unsaturated monomer exceeds 99% by weight, it is sensitive when mixed with a thermosetting amino resin. It is not preferable because the bond with the base is insufficient and the nonwoven fabric does not have sufficient strength. If the content of the ethylenically unsaturated monomer containing an amide group exceeds 30% by weight and the content of the other copolymerizable ethylenically unsaturated monomer is less than 70% by weight, the aqueous emulsion has a high viscosity, which is disadvantageous. Not preferable.

The composition ratio of the other ethylenically unsaturated monomer copolymerizable with the amide group-containing ethylenically unsaturated monomer is such that the Tg of the aqueous emulsion is 50 to 90.
It is optional only when it is set within the range of ° C.

The reason is that the Tg of the aqueous emulsion is
Is less than 50 ° C., the tensile strength of the nonwoven fabric subjected to the binder treatment at the time of heating is lowered, which is not preferable. Further, when it exceeds 90 ° C, the polymerization stability is insufficient and a gelled product is formed, and a stable aqueous emulsion cannot be produced. Therefore, the Tg of the aqueous emulsion is preferably set to 50 to 90 ° C, and more preferably 65 to 80 ° C.

The Tg of the aqueous emulsion referred to here is the value obtained from the equation 1 by the usual weight fraction method.

[0016]

[Formula 1] 1 / Tg = (W _A / Tg _A ) + (W _B / Tg _B ) W _A : Weight fraction of A component W _B : Weight fraction of B component Tg _A : Glass transition point of A component Temperature (K) Tg _B : Glass transition temperature (K) of B component

The emulsifier and polymerization initiator used in the present invention are not particularly limited. For example, as the emulsifier, an anionic or nonionic emulsifier can be used or used in combination. As the polymerization initiator, persulfates such as potassium persulfate and ammonium persulfate, peroxides such as hydrogen peroxide, benzoyl peroxide, t-butyl hydroperoxide and cumene hydroperoxide are generally used. Water-soluble initiators are preferred. Further, it is no problem to use a chain transfer agent, n-dodecyl mercaptan, t-dodecyl mercaptan or the like, which is usually used in emulsion polymerization in the present invention, if necessary.

Thermosetting amino resin (B) used in the present invention
The amino resin (hereinafter simply referred to as “amino resin”) is not particularly limited, and a commercially available amino resin can be used. The amino resin includes urea resin, melamine resin, and urea melamine resin. For example, Urea resin manufactured by Mitsui Toatsu Chemical Co., Ltd. is U-320, melamine resin is TMF, and urea melamine resin is U-350. Is mentioned. In the case of a urea resin, which is a type of amino resin, a general production method is such that the condensation reaction is carried out at a ratio of 1.0 to 3.0, where F / U is the molar ratio of formaldehyde (F) and urea (U). To do. Also,
In the case of a melamine resin, the condensation reaction is carried out at a ratio of 1.5 to 6.0 with the molar ratio of formaldehyde (F) and melamine (M) being F / M. Further, these urea resins and melamine resins may be used alone or in an arbitrary mixture.

The acrylamide polymer aqueous solution (C) in the present invention means a polymer formed from acrylamide and / or methacrylamide, or the maximum amount of acrylamide and / or methacrylamide with respect to all monomer components constituting the acrylamide polymer. It means a copolymer contained as a component, and especially 50 mol% of acrylamide and / or methacrylamide.
It is preferable to contain the above.

The acrylamide polymer aqueous solution (C) in the present invention preferably has a weight average molecular weight of 200,000 or more. If it is less than 200,000, the effect as a nonwoven fabric binder is significantly reduced, which is not preferable. The polymer concentration is not particularly limited, but is preferably 10% or more. 10%
If it is less than the above, there is no problem in use, but the cost per solid content becomes high, which is not preferable. Further, it is preferable that the viscosity is low in view of handling. The polymer concentration can be obtained by measuring the absolutely dry polymer concentration of the acrylamide polymer aqueous solution (C). Examples of the measuring method include a hot air drying method and a ket method.

The acrylamide polymer (C) of the present invention
As a typical example, acrylamide or methacrylamide or a salt thereof can be obtained by copolymerizing one or more of them. Further, by using a crosslinkable vinyl monomer, the acrylamide polymer of the present invention can be obtained. An aqueous solution can be easily obtained.

Specific examples of such crosslinkable vinyl monomers are methylene bis (meth) acrylamide, ethylene bis (meth) acrylamide, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate and triethylene glycol di (meth).
Examples thereof include bifunctional crosslinkable monomers such as acrylate and divinylbenzene, and polyfunctional crosslinkable monomers such as 1,3,5-triacryloylhexahydro-S-triazine, triallyl isocyanurate, and pentaerythritol triacrylate. be able to. The amount of these crosslinkable monomers is 0.01 to 5 mol% based on the total amount of all the monomers constituting the acrylamide polymer, but from the viewpoint of the uniformity of the branched crosslinked structure of the polymer, it is 0. 0
It is preferably from 1 to 2 mol%. These compounds may be used alone or in combination of two or more.

The acrylamide polymer (C) in the present invention can be copolymerized with various vinyl monomers other than acrylamide and / or methacrylamide. These include ionic monomers, hydrophilic monomers, hydrophobic monomers and the like, and one or more of these monomers can be applied.

Among the ionic monomers, examples of the anionic monomer include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and salts thereof, vinyl sulfonic acid, styrene sulfonic acid, acrylamidomethyl. Propane sulfonic acid and salts thereof include, as the cationic monomer, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-
Dimethylaminoethyl (meth) acrylamide, N, N
-Diethylaminoethyl (meth) acrylamide, N,
N-dimethylaminopropyl (meth) acrylamide,
Examples thereof include amines such as N, N-diethylaminopropyl (meth) acrylamide and salts thereof (including quaternary compounds).

Examples of the hydrophilic monomer include acetone acrylamide, N, N-dimethyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-
Diethyl (meth) acrylamide, N-propylacrylamide, N-acryloylpyrrolidine, N-acryloylpiperidine, N-acryloylmorpholine, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, various methoxypolyethylene glycol (meth) acrylates, Examples thereof include N-vinyl-2-pyrrolidone.

As the hydrophobic monomer, for example, N, N-
Di-n-propyl (meth) acrylamide, Nn-butyl (meth) acrylamide, Nn-hexyl (meth) acrylamide, Nn-octyl (meth) acrylamide, N-tert-octyl (meth) acrylamide, N-alkyl (meth) acrylamide derivatives such as N-dodecylacrylamide, Nn-dodecylmethacrylamide, N, N-diglycidyl (meth) acrylamide, N- (4-glycidoxybutyl) (meth) acrylamide, N- N- (ω-glycidoxyalkyl) (meth) acrylamide derivatives such as (5-glycidoxypentyl) acrylamide, N- (6-glycidoxyhexyl) acrylamide, methyl (meth) acrylate, ethyl (meth) acrylate , Butyl (meth) acrylate, lauryl (meth (Meth) acrylate derivatives such as acrylate, 2-ethylhexyl (meth) acrylate and glycidyl (meth) acrylate, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl chloride, vinylidene chloride, olefins such as ethylene, propylene and butene, styrene, Examples thereof include α-methylstyrene, butadiene, isoprene and the like.

The amount of the vinyl monomer used for the copolymerization varies depending on the kind of the vinyl monomer and the combination thereof, and although it cannot be generally stated, it is generally in the range of 0 to 50 mol%. It is preferably 0 to 20 mol%, more preferably 0.5 to 10 mol%.

Radical polymerization is preferred as the method for polymerizing the acrylamide polymer in the present invention. Although water is used as the polymerization solvent, it is possible to use an organic solvent such as alcohol in combination within a range that does not impair the dispersibility due to precipitation and precipitation of the polymer in an aqueous solution having the above concentration.

The method for polymerizing the acrylamide polymer in the present invention is as follows.
The batch polymerization may be carried out, but a semi-batch (semi-batch) polymerization method in which a part or all of the monomers are dropped into the reaction vessel to carry out the polymerization is more preferable.
By carrying out the semi-batch (semi-batch) polymerization method, not only is it easy to remove the heat of polymerization in the high-concentration monomer solution, but it is also easy to homogenize the branched and cross-linked structure of the polymer, and control the molecular structure. It will be possible.

The polymerization initiator is not particularly limited, but a water-soluble one is preferable. It may be added to the aqueous monomer solution all at once or may be added dropwise. As specific polymerization initiators, examples of persulfate-based and peroxide-based initiators include ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide, benzoyl peroxide, and tert-butyl peroxide. In this case, it is preferably used alone, but it can also be used as a redox polymerization initiator in combination with a reducing agent. Examples of the reducing agent include sulfite, bisulfite, low-order ionized salts such as iron, copper and cobalt, organic amines such as N, N, N ′, N′-tetramethylethylenediamine, aldose and ketose. And reducing sugars.

Azo compounds are also preferable initiators, and 2,2'-azobis-2-methylpropionamidine hydrochloride, 2,2'-azobis-2,4-dimethylvaleronitrile and 2,2'-azobis are also preferred. -N, N'-dimethyleneisobutylamidine hydrochloride, 2,2'-azobis-2
-Methyl-N- (2-hydroxyethyl) -propionamide, 2,2'-azobis-2- (2-imidazolin-2-yl) -propane and its salts, 4,4'-azobis-4-cyanoyoshi Herb acid and its salts can be used. Furthermore, it is also possible to use two or more of the above-mentioned polymerization initiators in combination. The amount of the polymerization initiator is generally 0.001 to 5% by weight based on the monomer.

The polymerization temperature is about 30 to 90 ° C. in the case of a single polymerization initiator, and the starting temperature in the case of a redox type polymerization initiator is lower, about 5 to 50 ° C. Further, it is not necessary to maintain the same temperature during the polymerization and may be appropriately changed as the polymerization proceeds, but since the temperature is generally raised by the heat of polymerization generated with the progress of the polymerization, it is necessary to add cooling if necessary. In some cases. The atmosphere in the polymerization container at that time is not particularly limited, but it is preferable to substitute an inert gas such as nitrogen gas for rapid polymerization.

The polymerization time is not particularly limited, but is generally 1 to 20 including the dropping time in the semi-batch (semi-batch) polymerization.
Time. The polymerization pH is not particularly limited, but the pH may be adjusted to carry out the polymerization if necessary. In that case, sodium hydroxide, potassium hydroxide, etc. can be used as pH adjusters.
Examples thereof include alkalizing agents such as ammonia, mineral acids such as phosphoric acid, sulfuric acid and hydrochloric acid, and organic acids such as formic acid and acetic acid.

The nonwoven fabric binder of the present invention can be obtained by mixing the thus obtained aqueous emulsion (A), amino resin (B) and aqueous acrylamide polymer solution (C). The mixing ratio is 1 total solids.
As 00 parts by weight, (A) :( B) :( C) = 3 to 9
6:96 to 3: 1 to 10 parts by weight, more preferably 10 to 78:78 to 10: 2 to 8 parts by weight, and most preferably 20 to 40:77 to 53: 3 to 7 parts by weight. Use to be.

When the amount of the aqueous emulsion (A) is less than 3 parts by weight based on the total amount of the binder, the treated non-woven fabric has a low elongation in the normal state, and when it exceeds 96 parts by weight, the treated non-woven fabric is in the normal state and under heat. The tension is low, which is not preferable.

Further, the non-woven fabric treated with the thermosetting amino resin (B) in an amount of less than 3 parts by weight based on all binders is
When the tensile strength in the normal state is low, and when it exceeds 96 parts by weight, the treated nonwoven fabric has low elongation in the normal state and heat, which is not preferable.

Further, when the amount of the acrylamide polymer aqueous solution (C) is less than 1 part by weight with respect to the total amount of the binder, the treated nonwoven fabric has insufficient anti-tension when heated, and when it exceeds 10 parts by weight, the binder liquid is Not only does the viscosity increase, the workability deteriorates, but the treated non-woven fabric has a higher tensile strength in the normal state and a higher tensile strength at the time of heating, but the elongation in the normal state becomes lower, which causes a new decrease in tear strength and water resistance. It is not preferred.

The non-woven fabric binder thus obtained is
Not only for a non-woven fabric for asphalt impregnation, but various additives such as a curing agent for an amino resin, a formalin catcher agent, and the like are added depending on the application, and it can be used as various non-woven fabric binders.

[0039]

[Reference Example 1]

Production of aqueous emulsions used in Examples and Comparative Examples. In a mixing tank equipped with a stirrer, 159 g of pure water, 1 g of sodium dodecylbenzenesulfonate (hereinafter abbreviated as DBS),
Styrene 40 g, methyl methacrylate 244 g, butyl acrylate 80 g, 2 hydroxyethyl methacrylate 8 g, methacrylic acid 8 g, methacrylamide 20 g
Was charged and stirred at room temperature for 30 minutes to obtain an emulsion a. Then, in a 1 L glass reactor equipped with a stirrer, a reflux condenser, a dropping device and a thermometer, 437 g of pure water and DBS were added.
1 g was charged, and under stirring in a nitrogen atmosphere, 2 g of potassium persulfate was added at a temperature of 75 ° C. to obtain solution b. Next, the previously prepared emulsion a was added to this solution b over 3 hours to cause a reaction, and the reaction was terminated over a further 3 hours. After the reaction solution was cooled to room temperature, aqueous ammonia was added as a neutralizing agent to adjust the pH to 8 to obtain an aqueous emulsion A1 having a target Tg of 60 ° C. Further, an aqueous emulsion of A2 to A5 was obtained by the same method except that the monomer composition was changed. The monomer composition and physical properties are shown in Table 1.

Reference Example 2 Thermosetting Amino Resin Used in Examples and Comparative Examples Selected from commercially available thermosetting amino resins of Mitsui Toatsu Chemicals, Inc., shown in Table 2.

Reference Example 3 Production of aqueous acrylamide polymer solution used in Examples and Comparative Examples. In the following,% means% by weight unless otherwise specified.
In addition, the weight average molecular weight was measured by Showa Denko KK Sh
ode ^(R) GPC SYSTEM-11 to Sho
-DexOHpak SB80M was connected, and a differential refractometer and a multi-angle light scattering detector manufactured by WYATT TECHNOLOGY were used together as detectors.

Reference Example 3-1 A five-necked flask (hereinafter referred to as a reaction vessel) equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port was charged with 228 g of pure water. The internal temperature was adjusted to 80 ° C. while blowing. On the other hand, a solution prepared by mixing 283 g of a 50% acrylamide aqueous solution, 0.31 g of methylenebisacrylamide and 30 g of isopropyl alcohol, and 60 g of an aqueous solution in which 0.24 g of 84% pure 4,4′-azobis-4-cyanovaleric acid was dissolved. Was uniformly added dropwise into the reaction container over 150 minutes. During this period, the temperature inside the reaction vessel was kept constant at 80 ° C. After the dropping was completed, the polymerization was continued at 80 ° C. for 3 hours, and the reaction was terminated by cooling to obtain an aqueous acrylamide polymer aqueous solution having a Brookfield viscosity of 13300 cps at 25 ° C. This polymer is designated as C1. 1 g of C1 was precisely weighed in an aluminum cup of known weight, diluted with about 1 g of pure water, and dried in a hot air drier at 105 ° C. for 3 hours to determine the absolute dry polymer concentration.
It was 5.6%. The weight average molecular weight of C1 measured by the above method was 366,000.

[Reference Example 3-2] 639 g of pure water and 360 g of 50% acrylamide aqueous solution were placed in a five-necked flask equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port.
Was charged, and the internal temperature was adjusted to 30 ° C. while blowing nitrogen gas. Next, 0.67 g of ammonium persulfate and 0.33 g of sodium bisulfite were added and reacted to obtain an aqueous acrylamide polymer aqueous solution. After cooling, the Brookfield viscosity at 25 ° C. was measured to be 5000 cps
Met. This polymer is designated as C2. Various physical properties of C2 were measured in the same manner as in Reference Example 3-1.

[Reference Example 3-3] 800 g of pure water and 200 g of 50% acrylamide aqueous solution were placed in a five-necked flask equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port.
Was charged, and the internal temperature was adjusted to 30 ° C. while blowing nitrogen gas. Next, 0.30 g of ammonium persulfate and 0.15 g of sodium bisulfite were added and reacted to obtain an aqueous acrylamide polymer aqueous solution. After cooling, the Brookfield viscosity at 25 ° C. was measured to be 12,500 cp
s. This polymer is designated as C3. Various physical properties of C3 were measured in the same manner as in Reference Example 3-1.

[Reference Example 3-4] 637 g of pure water and 360 g of 50% acrylamide aqueous solution were placed in a five-necked flask equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen gas inlet tube, and a dropping port.
Was charged, and the internal temperature was adjusted to 30 ° C. while blowing nitrogen gas. Next, 2.0 g of ammonium persulfate and 0.9 g of sodium bisulfite were added and reacted to obtain an acrylamide polymer aqueous solution. After cooling, the Brookfield viscosity at 25 ° C. was measured and found to be 1300 cps. This polymer is designated as C4. Various physical properties of C4 were measured in the same manner as in Reference Example 3-1. Reference Examples 3-1 to 3
Various physical property values of the polymer obtained in 4 are summarized in Table 3.

[0046]

[Table 1]

[0047]

[Table 2] U-350: urea-melamine resin TMF: melamine resin U-320: urea resin

[0048]

[Table 3] 1) AM: Acrylamide 2) MBA: Methylenebisacrylamide 3) Initiator A: 4,4′-azobis-4-cyanovaleric acid B: Ammonium persulfate and sodium bisulfite are used in a ratio of 2: 1 4) Initiator Amount: grams per mole of monomer 5) DPC: absolute dry polymer concentration 6) Mw: weight average molecular weight

Example 1 125 g of the aqueous emulsion A1 shown in Table 1 so that the solid content ratio of the aqueous emulsion, the thermosetting amino resin and the aqueous solution of the acrylamide polymer was 20: 75: 5.
And thermosetting amino resin B1 shown in Table 2; 341 g
And an aqueous solution of acrylamide polymer shown in Table 3; 4
1 g is weighed in a container equipped with a stirrer, and further 3 g of thermosetting amino resin curing agent (Catalyst P ... manufactured by Mitsui Toatsu Kagaku Co., Ltd.) and pure water so that the total concentration of the solution is 25%;
Was added and stirred and mixed for 3 minutes, and then the mixed solution was 30 cm in length.
Transfer to a pallet measuring 30 cm wide × 3 cm deep and have a basis weight of 1
200g of mangle after dipping 30g30cm of spunbond web made of polyester fiber of 00g / m ²
/ M ² and squeeze it for 5 minutes in a dryer set at 110 ° C, and then place it in a dryer set at 180 ° C for 3 minutes.
It was left for a minute to obtain the target nonwoven fabric. The basis weight of the nonwoven fabric after drying was 125 g / m ² .

Next, the nonwoven fabrics were evaluated by the following methods, and the results are shown in the result list of Table 4. [Evaluation of non-woven fabric] 1) Preparation of test piece The processed non-woven fabric was cut to prepare a test piece measuring 15 cm in length and 5 cm in width. 2) Tensile test Using a self-recording tensile tester (manufactured by Shimadzu Corporation), a tensile test was performed in an atmosphere of 20 ° C and 160 ° C.
The test condition is that the distance between chucks is 10 cm and the pulling speed is 2
The evaluation was made at 00 mm / min.

Examples 2 to 6 Nonwoven fabrics were prepared and evaluated in exactly the same manner as in Example 1 except that the binder ratio was adjusted to the composition shown in Table 4 (shown in parts). The results are shown in the evaluation column of Table 4.

Comparative Examples 1 to 4 Nonwoven fabrics were prepared and evaluated in exactly the same manner as in Example 1 except that the binder ratio was adjusted to the composition shown in Table 4 (shown in parts). The results are shown in the evaluation column of Table 4.

Comparative Example 5 A non-woven fabric binder was prepared in exactly the same manner as in Example 1 except that the binder ratio was adjusted to the composition shown in Table 4 (shown in parts). The viscosity was so high that the intended non-woven fabric could not be obtained.

[0054]

[Table 4]

[0055]

INDUSTRIAL APPLICABILITY The present invention is a non-woven fabric binder in which the tensile strength upon heating is much less than that of the prior art by using a specific aqueous emulsion. INDUSTRIAL APPLICABILITY The present invention enables the production of a nonwoven fabric excellent in both tensile strength under heat and flexibility, has an industrial significance, and is particularly useful as a binder for an asphalt-impregnated nonwoven fabric used for waterproofing a building. .

Claims (3)

[Claims] 1. A non-woven fabric binder comprising an aqueous emulsion (A), a thermosetting amino resin (B) and an aqueous acrylamide polymer solution (C). 2. The total solid content of the aqueous emulsion (A), the thermosetting amino resin (B) and the aqueous solution of the acrylamide polymer (C) is 100 parts by weight, and each is 3 parts.
The binder for non-woven fabric according to claim 1, wherein the binder is a mixture of 96:96 to 3: 1 to 10 parts by weight. 3. The aqueous emulsion (A) contains 1 to 30% by weight of an amide group-containing ethylenically unsaturated monomer, and another ethylenically unsaturated monomer 9 copolymerizable therewith.
The non-woven fabric binder according to claim 1, which is obtained by emulsion polymerization of 9 to 70% by weight and has a glass transition temperature (Tg) of 50 to 90 ° C.