JP2006022424A - Reinforcing agent for nonwoven fabric for asphalt roofing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforcing agent for nonwoven fabric for asphalt roofing, having good adhesion to nonwoven fabric of a polyester-based fiber, increasing strength characteristics and imparting heat resistance not to cause morphological deformation and excellent in safety. <P>SOLUTION: The reinforcing agent for nonwoven fabric for asphalt roofing comprises a water-based dispersion (A) and starch, wherein te dispersion comprises a thermally reactive polyurethane having 1,500-50,000 number-average molecular weight, the solid of the starch is compounded to be 50-300 pts.wt. per 100 pts.wt. solid of the water-based dispersion (A), and the thermally reactive polyurethane contains 2-18 wt.% blocked isocyanate expressed in terms of reclaimed isocyanate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a non-woven fabric reinforcing agent for asphalt roofing comprising an aqueous dispersion of a heat-reactive polyurethane resin as an active ingredient.

Asphalt roofing in which a non-woven fabric made of synthetic fibers such as vinylon is impregnated with asphalt is widely used as a waterproof sheet or the like in the fields of civil engineering and building materials.
By the way, since the nonwoven fabric used for asphalt roofing is impregnated with high-temperature asphalt at 200 ° C. or higher as well as a requirement for strength properties, it requires a high degree of heat resistance so as not to cause deformation.

  Due to such requirements, the nonwoven fabric used for asphalt roofing is, for example, a nonwoven fabric, glass fiber, or polyvinyl alcohol obtained by impregnating a polyester fiber-polyvinyl alcohol fiber blended base fabric with a polyvinyl alcohol or starch-based resin as a main component. A two-layer nonwoven fabric (Patent Document 1) made of a base fiber and a polyester fiber is used.

However, the nonwoven fabric using glass fiber or polyvinyl alcohol fiber has a problem of high cost because glass fiber or polyvinyl alcohol fiber is expensive.
In addition, since the polyvinyl alcohol fiber is a hydrophilic resin, it has a problem of poor water resistance and poor dimensional stability when used for asphalt roofing.
For this reason, there is a demand for the use of polyester fibers for the base fabric of the nonwoven fabric from the viewpoint of price, performance and the like.
However, when only the polyester fiber non-woven fabric is used, there is a problem in that the shape of the non-woven fabric is deformed due to a decrease in strength characteristics and extremely low heat resistance against high-temperature asphalt.

In order to solve this problem, various studies have been made to supplement the performance of the nonwoven fabric by impregnating the nonwoven fabric with resin. For example, a polyester fiber nonwoven fabric impregnated with a reinforcing agent composed of an acrylic resin and a melamine crosslinking agent has been studied (Patent Document 2). However, the reinforcing agent does not improve strength properties because of its low adhesion to the non-woven fabric, and is insufficient in terms of heat resistance that does not cause morphological deformation. Have the problem of
Therefore, the present condition is that the thing which has the performance which can be satisfied as a reinforcing agent used for the nonwoven fabric of a polyester-type fiber has not been obtained yet.
JP-A-8-246358 Japanese Patent Publication No. 3-67150

  In view of the above problems, the present invention provides a non-woven fabric reinforcing agent for asphalt roofing that has good adhesion to a nonwoven fabric of polyester fibers, improves strength characteristics, provides heat resistance so as not to cause deformation, and is excellent in safety. It is an issue to provide.

  The inventors of the present invention, as a result of intensive research to solve the above problems, have resulted in a reinforcing agent comprising a specific aqueous dispersion and starch, or a specific aqueous dispersion and starch and a specific epoxy crosslinking agent. The present inventors have found that the above-described problems can be solved by a reinforcing agent comprising the following, and have completed the present invention.

  That is, in the present invention, an aqueous dispersion (A) comprising a heat-reactive polyurethane resin having a number average molecular weight of 1,500 to 50,000 and starch are added to 100 parts by weight of the solid content of the aqueous dispersion (A). The starch is blended so that the solid content of the starch is 50 to 300 parts by weight, and the aqueous dispersion (A) contains the compound (B) having two or more active hydrogen atoms in the molecule and the molecule The heat-reactive polyurethane resin obtained by reacting the compound (C) having at least one active hydrogen atom and a carboxyl group with the organic polyisocyanate (D) and the blocking agent (E) is dispersed in water. The heat-reactive polyurethane resin contains 2 to 18% by weight of a blocked isocyanate group in terms of recycled isocyanate group, and is a non-woven fabric supplement for asphalt roofing. To provide a dosage.

  In the present invention, an aqueous dispersion (A) comprising a heat-reactive polyurethane resin having a number average molecular weight of 1,500 to 50,000, starch and an epoxy-based crosslinking agent (F) are mixed with the aqueous dispersion (A ) In a solid content of 50 to 300 parts by weight and a solid content of the epoxy crosslinking agent (F) of 10 to 80 parts by weight, The dispersion (A) comprises a compound (B) having two or more active hydrogen atoms in the molecule, a compound (C) having at least one active hydrogen atom and a carboxyl group in the molecule, and an organic polyisocyanate ( D) is obtained by dispersing the thermally reactive polyurethane resin obtained by reacting the blocking agent (E) in water, and the thermally reactive polyurethane resin has a blocked isocyanate group regenerated isocyanate. 2 to 18% by weight in terms of conversion, and the epoxy crosslinking agent (F) has at least two glycidyl groups in the molecule, has an epoxy equivalent of 110 to 300, and a water content of 20% or more. A non-woven fabric reinforcing agent for asphalt roofing is provided.

Since the nonwoven fabric reinforcing agent for asphalt roofing according to the present invention has excellent adhesion to nonwoven fabrics made of various synthetic fibers, particularly adhesion to nonwoven fabrics of polyester fibers, it can improve the strength characteristics of the nonwoven fabric.
In addition, the nonwoven fabric impregnated with the nonwoven fabric reinforcing agent for asphalt roofing according to the present invention is excellent in heat resistance even when impregnated with high-temperature asphalt, and therefore hardly deforms.
Furthermore, since the nonwoven fabric reinforcing agent for asphalt roofing according to the present invention is aqueous, it is excellent in environmental performance and safety.

An embodiment of the nonwoven fabric reinforcing agent for asphalt roofing according to the present invention will be described.
The nonwoven fabric reinforcing agent for asphalt roofing of this embodiment consists of an aqueous dispersion (A) and starch, or an aqueous dispersion (A), starch, and an epoxy-type crosslinking agent (F).

Each component which comprises the said water dispersion (A) used for this embodiment is demonstrated.
The aqueous dispersion (A) used in the present embodiment comprises a compound (B) having two or more active hydrogen atoms in the molecule and a compound (C) having at least one active hydrogen atom and a carboxyl group in the molecule. ), An organic polyisocyanate (D), and a blocking agent (E), which are obtained by dispersing a heat-reactive polyurethane resin having a number average molecular weight of 1,500 to 50,000 in water, The heat-reactive polyurethane resin contains 2 to 18% by weight of a blocked isocyanate group in terms of regenerated isocyanate group.

The compound (B) has two or more hydroxyl groups, amino groups or mercapto groups in the molecular end or in the molecule, for example, known polyether, polyester, polyether ester, polythioether, polyacetal, polybutadiene, polysiloxane Etc.
A compound having two or more hydroxyl groups at the molecular end is preferable. The molecular weight of the compound (B) is preferably in the range of 50 to 5,000.

Examples of the compound (B) include ethylene glycol, diethylene glycol, butanediol, propylene glycol, dipropylene glycol, hexanediol, bisphenol A, bisphenol B, bisphenol S, hydrogenated bisphenol A, dibromobisphenol A, 1 , 4-cyclohexanedimethanol, dihydroxyethyl terephthalate, hydroquinone dihydroxyethyl ether, trimethylolpropane, glycerin, pentaerythritol, diglycerin and other polyhydric alcohols, alkylene derivatives thereof, polyhydric alcohols and alkylene derivatives and polyhydric carboxylic acids , Polyhydric carboxylic acid anhydride, or esterified product from polyhydric carboxylic acid ester, polycarbonate polyol, polytetramethyle Glycols, polycaprolactone polyols, polybutadiene polyols, polythioether polyols - le, polyacetal polyol - can be exemplified Le compound or a modified product such as - le, a fluorine polyol, silicon polyol, castor oil polyol - polio like Le.
These compounds (B) can be used alone or in combination of two or more.

Examples of the compound (C) include glycolic acid, malic acid, glycine, aminobenzoic acid, alanine, dimethylolpropionic acid, dimethylolbutanoic acid, and other hydroxy acids and aminocarboxylic acids.
These compounds (C) can be used alone or in combination of two or more.

Examples of the organic polyisocyanate (D) include alicyclic polyisocyanates and aromatic polyisocyanates. Moreover, polynuclear bodies, such as a dimer and a trimer of alicyclic polyisocyanate and aromatic polyisocyanate, and also a methylene bridge | crosslinking structure, can be mentioned.
Examples of the alicyclic polyisocyanate include isophorone diisocyanate, hydrogenated xylylene diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexylene diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, and the like. Can be mentioned.
Aromatic polyisocyanates include tolylene diisocyanate, 2,2′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-dibenzyl diisocyanate, 1,5 -A naphthylene diisocyanate, a xylylene diisocyanate, a 1, 3- phenylene diisocyanate, a 1, 4- phenylene diisocyanate etc. can be mentioned. Moreover, polyphenylene polymethylene polyisocyanate etc. can be mentioned.
Among these organic polyisocyanates (D), aromatic isocyanates are preferable, and specifically, polymeric MDI such as polyphenylene polymethylene polyisocyanate is preferable.
By using an aromatic polyisocyanate, the high cohesive strength of the aromatic ring has the effect of improving not only heat resistance but also solvent resistance, chemical resistance, water resistance and moisture resistance.
In addition, these organic polyisocyanate (D) can also be used individually or in combination of 2 or more types.

As said blocking agent (E), what reproduce | regenerates an isocyanate group by the heat processing conventionally used conventionally can be used.
Examples of the blocking agent (E) include oximes such as acetone oxime, methyl ethyl ketoxime, butanone oxime, cyclohexanone oxime, cyclopentanone oxime, acetophenone oxime, benzophenone oxime, phenol, methylphenol, butylphenol, octylphenol, nonylphenol and the like. Alkylphenols, lactams such as ε-caprolactam, imidazoles such as imidazole, methylimidazole, ethylimidazole and pyrazole, heterocyclic compounds, alcohols such as isopropyl alcohol, butyl alcohol and ethyl cellosolve, ethyl acetoate, malonic acid Active methylene group-containing compounds such as diethyl and ethyl acetoate, sodium bisulfite, potassium bisulfite, ammonium bisulfite It can be mentioned blocking agent bisulfite systems such as um.
Of these blocking agents, oxime blocking agents are preferred.
These blocking agents can be used alone or in combination of two or more.
The nonwoven fabric reinforcing agent obtained by combining the oxime-based blocking agent and the aromatic polyisocyanate has an effect that good cross-linking properties with the nonwoven fabric can be obtained even under a relatively low temperature condition of 120 ° C. or higher. In addition, an aqueous dispersion of a heat-reactive polyurethane resin obtained by combining the oxime-based blocking agent and the aromatic polyisocyanate is an inexpensive one-part water dispersion having good storage stability and latent crosslinking characteristics. It can also be used as a body.

The heat-reactive polyurethane resin has a number average molecular weight of 1,500 to 50,000, preferably 2,000 to 20,000.
When the number average molecular weight is less than 1,500, there is a problem that the cross-linked site adhering to the nonwoven fabric becomes too hard and adhesion is lowered.
In addition, when the number average molecular weight exceeds 50,000, synthesis becomes difficult, and the content of blocked isocyanate groups, which are heat-reactive groups, is reduced.
The number average molecular weight is measured by the method described in the examples.

The heat-reactive polyurethane resin has a blocked isocyanate group in the side chain and / or molecular end of the polymer.
As a method for synthesizing the thermally reactive polyurethane resin having a blocked isocyanate group at the side chain and / or molecular end of the polymer, after preparing a urethane prepolymer having an isocyanate group at the molecular end, the blocking agent (E Or a part of the isocyanate group of the organic polyisocyanate (D) is reacted with the blocking agent (E), and then the remaining organic polyisocyanate (D) is reacted. There is a way.

The heat-reactive polyurethane resin contains 2 to 18% by weight of a blocked isocyanate group in terms of regenerated isocyanate group, and preferably 2 to 12% by weight in terms of regenerated isocyanate group.
When the blocked isocyanate group is contained in an amount less than 2% by weight in terms of recycled isocyanate group, the crosslinking effect is weakened, and desired strength characteristics and heat resistance performance are not exhibited.
Further, when the blocked isocyanate group exceeds 18% by weight in terms of recycled isocyanate group, the asphalt roofing molded product becomes too hard and it becomes difficult to handle.
The blocked isocyanate group means a group in which the blocking agent is dissociated by heat treatment to regenerate and crosslink the isocyanate group, or a group that crosslinks with a hydroxyl group or the like by heat treatment.

The aqueous dispersion (A) used in the present embodiment is obtained by dispersing the heat-reactive polyurethane resin in water.
There are various methods for producing the aqueous dispersion (A). In this embodiment, the thermally reactive polyurethane resin is synthesized in a hydrophilic low-boiling solvent such as methyl ethyl ketone or isopropyl alcohol. Next, a method in which a salt forming agent is allowed to act on the heat-reactive polyurethane resin and emulsified in water can be used.
This method uses a salt-forming agent that forms a salt with respect to the compound (C) used in the production of the heat-reactive polyurethane resin.
Examples of the salt forming agent include metal hydroxides such as sodium hydroxide and calcium hydroxide, and tertiary amine compounds such as ammonia, trimethylamine, triethylamine, and dimethylaminoethanol.

  The aqueous dispersion (A) used in the present embodiment includes the compound (B), the compound (C) and the organic polyisocyanate (D) in a solid content of 1,000 atomic weight of the aqueous dispersion (A). Total aromatic ring and aliphatic ring represented by chemical structural formula (1-a, 1-b, 1-c) or chemical structural formula (2-a, 2-b, 2-c) The number is 2 or more, preferably 2 to 6.

When the total number of aromatic rings and aliphatic rings is less than 2, it is not preferable because heat resistance, solvent resistance, water resistance and the like are lowered.
In addition, the method of calculating | requiring the total number of an aromatic ring and an aliphatic ring in 1,000 atomic weight calculates the total number of an aromatic ring and an aliphatic ring from the preparation ratio of each component.

In the aqueous dispersion (A) used in the present embodiment, the acid value of the carboxyl group in the aqueous dispersion (A) is 10 to 60 mgKOH / g, and preferably 10 to 40 mgKOH / g.
When the acid value is less than 10 mgKOH / g, the water dispersion of the heat-reactive polyurethane resin is weak, so the water dispersion does not become a water dispersion, so that sedimentation, separation, etc. occur and storage stability decreases. There is a risk of doing.
Further, when the acid value exceeds 60 mgKOH / g, the water dispersibility of the water dispersion made of the heat-reactive polyurethane resin is good, but the moisture resistance of the processed nonwoven fabric may be lowered.
In addition, an acid value is measured using the method of an Example description.

In the nonwoven fabric reinforcing agent for asphalt roofing according to the present embodiment, the water dispersion (A) and starch have a solid content of the starch of 50 to 300 weight parts per 100 weight parts of the solid content of the water dispersion (A). It is blended so that it becomes a part.
When the solid content of starch is less than 50 parts by weight, there is a problem that the heat resistance of the reinforcing agent is lowered and the dimensional stability at high temperature is lowered.
Moreover, when the solid content of starch exceeds 300 parts by weight, there is a problem that the moisture resistance of the reinforcing agent is lowered, and it is easy to absorb moisture at high humidity.

  Examples of the starch include those produced industrially from starch stored in seeds such as potato, corn, wheat, glutinous rice, glutinous rice, tapioca and banana, roots, rhizomes, and the like. Moreover, in order to improve the solubility, it is also possible to use a starch obtained by allowing an acid or amylase to act on starch. Note that starch has the effect of improving heat resistance.

In the nonwoven fabric reinforcing agent for asphalt roofing according to the present embodiment, the water dispersion (A), the starch, and the epoxy-based crosslinking agent (F) are used in the solid content of 100 parts by weight of the water dispersion (A). It is blended so that the solid content of starch is 50 to 300 parts by weight and the fixed part of the epoxy-based crosslinking agent (F) is 10 to 80 parts by weight, preferably the solid content of the aqueous dispersion (A) It mix | blends so that the solid content of this starch may be 100-250 weight part and the solid content of this epoxy type crosslinking agent (F) may be 30-50 weight part with respect to 100 weight part.
By mix | blending in this range, various performances, such as heat resistance, solvent resistance, and water resistance, can be improved.
When the solid content of the epoxy-based crosslinking agent (F) is less than 10 parts by weight, there is a problem that the adhesiveness with the nonwoven fabric is lowered.
Moreover, when solid content of an epoxy-type crosslinking agent (F) exceeds 80 weight part, various performances, such as solvent resistance, heat resistance, and water resistance, will fall.

The epoxy-based crosslinking agent (F) has at least two or more glycidyl groups in the molecule, has an epoxy equivalent of 110 to 300 and a water content of 20% or more, and preferably has 2 glycidyl groups in the molecule. ˜6, epoxy equivalent is 110 to 300, and water solubility is 50 to 100%.
When the number of glycidyl groups in the molecule is less than 2, adhesion, solvent resistance, heat resistance and the like are lowered.
When the epoxy equivalent is less than 110, various functions such as adhesion, solvent resistance, heat resistance and water resistance are lowered.
Moreover, when epoxy equivalent exceeds 300, various functions, such as solvent resistance, heat resistance, and water resistance, decline on the contrary.
If the water content is less than 20%, it becomes impossible to mix uniformly when the reinforcing agent is added, so that the stability of the aqueous dispersion is lowered, and it becomes non-uniform enough when adhered to the nonwoven fabric. Has a problem that it is impossible to achieve a satisfactory performance.
In addition, an epoxy equivalent is measured by the method of an Example description, and a unit is g / eq.

  Examples of the epoxy-based crosslinking agent (F) include sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, and the like.

  In order to make various additives such as thickeners, leveling agents, antifoaming agents, film-forming aids and the like suitable for the purpose of processing workability etc., the nonwoven fabric reinforcing agent for asphalt roofing of this embodiment The nonwoven fabric reinforcing agent can be blended within a range that does not deteriorate the performance. Further, for example, an acrylic emulsion or an SBR (styrene-butadiene copolymer) emulsion can be blended within a range that does not deteriorate the performance of the nonwoven fabric reinforcing agent.

Examples of the method for attaching the nonwoven fabric reinforcing agent for asphalt roofing of the present embodiment to the nonwoven fabric include a spray method, a dipping treatment method, a roller coater method, and the like.
Nonwoven fabrics include polyester-based non-woven fabrics such as polyethylene terephthalate of long fibers or short fibers, polybutylene terephthalate, polyvinyl-based non-woven fabrics, polyolefin-based non-woven fabrics such as polyethylene and polypropylene, polyamide-based non-woven fabrics such as nylon 6 and nylon 66, Although glass fiber etc. are mentioned and can be used individually or in combination, this invention does not limit the kind of nonwoven fabric.
Of these, polyester-based nonwoven fabrics are preferable from the viewpoint of cost.
Polyester-based nonwoven fabrics have not been put to practical use due to lack of heat resistant formability, strength, etc. with acrylic resins, starches, etc., which are conventional reinforcing agents, but by using the nonwoven fabric reinforcing agent for asphalt roofing of the present invention, Excellent physical properties can be obtained at a low cost.

The adhesion amount with respect to the nonwoven fabric of the nonwoven fabric reinforcing agent (solid content) for asphalt roofing of this embodiment is 10 to 50% by weight, preferably 20 to 30% by weight.
When the adhesion amount is less than 10% by weight, there is a problem that heat resistance and strength characteristics are deteriorated.
Moreover, when it exceeds 50 weight%, there exists a problem that the processed nonwoven fabric becomes hard and handling becomes difficult.
Here, the non-woven fabric reinforcing agent for asphalt roofing (solid content) refers to the remainder obtained by removing moisture from the non-woven fabric reinforcing agent for asphalt roofing.

The nonwoven fabric reinforcing agent for asphalt roofing of the present embodiment is impregnated with a predetermined amount into a nonwoven fabric, the nonwoven fabric is dried to remove moisture, and then heat treated at 100 ° C. to 200 ° C. to obtain a nonwoven fabric molding for asphalt roofing.
Asphalt roofing is obtained by immersing the nonwoven fabric molding for asphalt roofing in molten asphalt.
The asphalt roofing nonwoven fabric molding using the asphalt roofing nonwoven fabric reinforcing agent of the present embodiment is excellent in heat-resistant formability, strength characteristics, etc., so that strain hardly remains even when immersed in molten asphalt. .
Therefore, the asphalt roofing produced using the nonwoven fabric reinforcing agent for asphalt roofing of the present embodiment can sufficiently exhibit the functions required when constructed as a waterproof sheet or the like.

  The nonwoven fabric reinforcing agent for asphalt roofing according to the present embodiment is easy to use because it is a one-component, and has good stability against long-term storage. Moreover, since the nonwoven fabric reinforcing agent for asphalt roofing is aqueous, it can be safely used without volatilization of an organic solvent or the like.

  The nonwoven fabric reinforcing agent for asphalt roofing of the present embodiment functions well not only in asphalt roofing moldings but also in fields such as nonwoven fabrics and papers that are particularly required for heat resistance used in the automobile industry, electrical industry, etc. Is.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

(Number average molecular weight measurement method)
The number average molecular weight was measured from the relative molecular weight of standard polystyrene by gel filtration chromatography (GPC method). In Synthesis Example 4 and Synthesis Example 5, measurement was performed after all isocyanate groups were blocked with diethylamine.
An instrument made by Shimadzu Corporation was used as the GPC body, a column temperature of 40 ° C., a pump flow rate of 1 ml / min, and RI (SHIMADZU SPD-6A, RID-6A) as the detector. The data device obtained the molecular weight from the standard polystyrene equivalent molecular weight using a standard polystyrene calibration curve (calibration at a molecular weight of 500 or more) having a known molecular weight in advance.
Column used: Tosoh TSK-GEL G-1000H _XL x 2, TSK-GEL G-2000H _XL x 1, TSK-GEL G-3000H _XL x 1, TSK-GEL G-4000H _XL x 1 The column used is (TSK-GEL G-4000H _XL x 1) + (TSK-GEL G-3000H _XL x 1) + (TSK-GEL G-2000H _XL x 1) + (TSK-GEL G-1000H _XL x 2) Used in series in this order.
Mobile phase: Tetrahydrofuran Injection volume: 10 μl
Sample concentration: 2% (w / v)

(Measurement method of acid value)
The acid value was measured according to JIS K0070-1992.

(Measurement method of epoxy equivalent)
The epoxy equivalent was measured according to JIS K 7236.

(Synthesis Example 1)
In methyl ethyl ketone solvent, 100 parts by weight of bisphenol A alkylene derivative (ethylene oxide 4 mol adduct of bisphenol A, number average molecular weight 400), 270 parts by weight of polymeric MDI (number average molecular weight 360, functional group number 2.7), dimethylol 33.5 parts by weight of propionic acid was added and the reaction was carried out at a system temperature of 75 ° C. to obtain an isocyanate group-containing urethane prepolymer. Next, 88 parts by weight of methyl ethyl ketoxime was added at an internal temperature of 55 ° C., a blocking reaction was carried out, and a thermally reactive polyurethane resin containing 10.5% by weight of blocked isocyanate groups in terms of regenerated isocyanate groups (number average) The molecular weight was 2,000 and the number of aromatic rings in the 1,000 atomic weight was 5.1). The thermally reactive polyurethane resin was emulsified with an aqueous caustic soda solution, and then the methyl ethyl ketone solvent was distilled off under reduced pressure to obtain an aqueous dispersion 1.

(Synthesis Example 2)
An aqueous dispersion 2 was obtained using the same method as in Synthesis Example 1 except that the reagents and their amounts were changed to those shown in Table 1.
Incidentally, a heat-reactive polyurethane resin containing 5.8% by weight of a blocked isocyanate group in terms of regenerated isocyanate group (number average molecular weight 3,440, aromatic ring number in 1,000 atomic weight: 2.6) Obtained.

(Synthesis Example 3)
An aqueous dispersion 3 was obtained using the same method as in Synthesis Example 1 except that the reagents and amounts thereof were changed to those shown in Table 1.
A heat-reactive polyurethane resin containing 7.3% by weight of blocked isocyanate groups in terms of recycled isocyanate groups (number average molecular weight 2,760, aromatic ring number in 1,000 atomic weight: 2.9) Obtained.

(Synthesis Example 4)
An aqueous dispersion 4 was obtained using the same method as in Synthesis Example 1 except that the reagents and amounts thereof were changed to those shown in Table 1.
A heat-reactive polyurethane resin containing 5.8% by weight of blocked isocyanate groups in terms of recycled isocyanate groups (number average molecular weight 2,440, aromatic number in 1,000 atomic weights: 4.1) was obtained. It was.

(Synthesis Example 5)
100 parts by weight of polyester polyol (polyester polyol composed of 1,6-hexanediol, adipic acid and isophthalic acid, number average molecular weight 1,700) in methyl ethyl ketone solvent, 9 parts by weight of 1,4-butanediol, trimethylolpropane After adding 80 parts by weight of tolylene diisocyanate to 8 parts by weight and carrying out a reaction for 60 minutes at an internal temperature of 75 ° C., 12 parts by weight of dimethylolpropionic acid, 16 parts by weight of polyethylene glycol (number average molecular weight 600) Part, an amine catalyst (triethylamine) was added, and the reaction was carried out at a system temperature of 75 ° C. to obtain an isocyanate group-containing urethane prepolymer. Next, 16 parts by weight of methyl ethyl ketoxime was added at a system temperature of 55 ° C., a blocking reaction was carried out, and a thermally reactive polyurethane resin containing 3.5% by weight of blocked isocyanate groups in terms of regenerated isocyanate groups (number average) The molecular weight was 3,940 and the number of aromatic rings in the 1,000 atomic weight was 1.9). The heat-reactive polyurethane resin was mixed with 7.2 parts by weight of triethylamine, emulsified in water, and then 2.9 parts by weight of a chain extender triethylenetetramine (corresponding to 1.5% by weight in terms of recycled isocyanate group). The mixture was added and reacted, and the methyl ethyl ketone solvent was distilled off under reduced pressure to obtain an aqueous dispersion 5.

(Synthesis Example 6)
In a methyl ethyl ketone solvent, 65.5 parts by weight of polymeric MDI (number average molecular weight 360, functional group number 2.7) is added to 100 parts by weight of polypropylene glycol (number average molecular weight 1,100), and the system temperature is 75 ° C. The urethane prepolymer containing 7.8% by weight of free isocyanate groups (with respect to the total amount of polypropylene glycol and polymeric MDI) was obtained. Next, 19 parts by weight of methyl ethyl ketoxime was added at an internal temperature of 55 ° C. to carry out a blocking reaction, and a thermally reactive polyurethane resin containing 5.5% by weight of blocked isocyanate groups in terms of regenerated isocyanate groups (several The average molecular weight was 2,250, and the number of aromatic rings in the 1,000 atomic weight was 2.4). After adding 67 parts by weight of a 20% sodium taurate aqueous solution to the heat-reactive polyurethane resin and emulsifying it in water, the methyl ethyl ketone solvent was distilled off under reduced pressure to obtain an aqueous dispersion 6.

(Synthesis Example 7)
An aqueous dispersion 7 was obtained using the same method as in Synthesis Example 1 except that the reagents and amounts thereof were changed to those shown in Table 1.
A heat-reactive polyurethane resin containing 7.8% by weight of blocked isocyanate groups in terms of regenerated isocyanate groups (number average molecular weight 1,250, aromatic ring number in 1,000 atomic weight: 4.0) Obtained.

(Synthesis Example 8)
In methyl ethyl ketone solvent, 100 parts by weight of polyester polyol (polyester polyol comprising 1,6-hexanediol and adipic acid and isophthalic acid, number average molecular weight 1,700), 16 parts by weight of 1,4-butanediol, trimethylolpropane 1 After adding 69 parts by weight of tolylene diisocyanate to 5 parts by weight and carrying out the reaction at a system temperature of 75 ° C., 11 parts by weight of dimethylolpropionic acid, 15 parts by weight of polyethylene glycol (number average molecular weight 600), An amine catalyst (triethylamine) was added, and the reaction was carried out at a system temperature of 75 ° C. to obtain an isocyanate group-containing urethane prepolymer. Next, 1.8 parts by weight of methyl ethyl ketoxime was added at an internal temperature of 55 ° C., a blocking reaction was carried out, and a thermally reactive polyurethane resin containing 0.4% by weight of blocked isocyanate groups in terms of regenerated isocyanate groups ( The number average molecular weight was 8,140, and the number of aromatic rings in the 1,000 atomic weight was 2.1). The heat-reactive polyurethane resin was mixed with 8.3 parts by weight of triethylamine and emulsified in water, and then the methyl ethyl ketone solvent was distilled off under reduced pressure to obtain an aqueous dispersion 8.

(Synthesis Example 9)
In methyl ethyl ketone solvent, 100 parts by weight of polyester polyol (polyester polyol comprising 1,6-hexanediol, adipic acid and isophthalic acid, number average molecular weight 1,700), polymeric MDI (number average molecular weight 360, functional group number 2.7) ) 63.5 parts by weight and 7.9 parts by weight of dimethylolpropionic acid were added and the reaction was carried out at a system temperature of 75 ° C. to obtain a heat-reactive polyurethane resin containing an isocyanate group (number average molecular weight 3 , 100, 1,000 atomic weight: 3.0 aromatic rings). The heat-reactive polyurethane resin was emulsified with an aqueous caustic soda solution, and at the same time, chain elongation was performed with the water of the emulsification. Obtained.

  The amounts of reagents used in Synthesis Examples 1 to 9 are shown in Table 1.

＊１：ビスフェノールＡアルキレン誘導体：ビスフェノールＡのエチレンオキサイド４モル付加物、数平均分子量４００
＊２：ポリエステルポリオール：1,6-ヘキサンジオールとアジピン酸及びイソフタル酸とからなるポリエステルポリオール、数平均分子量１,７００
＊３：ポリプロピレングリコール：数平均分子量１,１００
＊４：ポリメリックＭＤＩ：数平均分子量３６０、官能基数２．７
＊５：トリレンジイソシアネート：数平均分子量１７４．２、官能基数２
＊６：ポリエチレングリコール：数平均分子量６００

* 1: Bisphenol A alkylene derivative: Bisphenol A ethylene oxide 4 mol adduct, number average molecular weight 400
* 2: Polyester polyol: Polyester polyol composed of 1,6-hexanediol, adipic acid and isophthalic acid, number average molecular weight 1,700
* 3: Polypropylene glycol: Number average molecular weight 1,100
* 4: Polymeric MDI: number average molecular weight 360, functional group number 2.7
* 5: Tolylene diisocyanate: number average molecular weight 174.2, functional group number 2
* 6: Polyethylene glycol: Number average molecular weight 600

Example 1
A nonwoven fabric reinforcing agent comprising the aqueous dispersion obtained in Synthesis Example 1, starch, and an epoxy-based crosslinking agent (sorbitol polyglycidyl ether, 4 glycidyl groups, epoxy equivalent 166) is used as the aqueous dispersion (solid content) of 100 weight. Part: starch (solid content) 230 parts by weight: epoxy-based crosslinking agent (solid content) 40 parts by weight, and the non-woven fabric in 100% polyester web (web weight 120 g / m ² ) having a fiber cut length of 120 mm After impregnation so that the adhesion amount of the reinforcing agent (solid content) was 30% by weight, forced drying was performed in an atmosphere of 120 ° C. for 5 minutes to obtain the resin-impregnated polyester nonwoven fabric. The resin-impregnated non-woven fabric was cut into 20 cm × 5 cm, and the high elongation was measured under the measurement conditions of 10 cm between sandwiches and a pulling speed of 100 mm / min. Further, the resin-impregnated nonwoven fabric was cut into 5 cm × 15 cm, immersed in silicon oil at 200 ° C. for 5 seconds, and the dimensional change (longitudinal direction and width direction) was measured to evaluate the heat resistance.
As the starch, Sanwa Starch Co., Ltd., trade name: corn starch was used.
The results are shown in Table 2.

(Example 2) to (Comparative Example 10)
Non-woven fabric in the same manner as in Example 1 except that the water dispersion, starch, and epoxy-based crosslinking agent obtained in the synthesis example were those shown in Table 2 and the blending ratio was changed to the ratio shown in Table 2. The reinforcing agent was adjusted, and the same test as in Example 1 was performed using the nonwoven fabric reinforcing agent.
The results and the blending ratio of the reagents are shown in Table 2.

(Comparative Example 11)
The polyester non-woven fabric similar to that used in Example 1 was treated under the same conditions using 100 parts by weight of solids of starch to obtain a resin-impregnated polyester non-woven fabric. Using the resin-impregnated nonwoven fabric, the strength measurement and the heat resistance test were performed under the same measurement method and measurement conditions as in Example 1. The results are also shown in Table 2.

(Comparative Example 12)
The same test as in Comparative Example 11 was performed except that polyvinyl alcohol (Kuraray Co., Ltd., trade name: Kuraray PVA-217) was used instead of starch and 100 parts by weight of solid content was used. The results are shown in Table 2.

エポキシ系架橋剤(*1)：ソルビトールポリグリシジルエーテル：グリシジル基４個、エポキシ当量１６６（商品名：ディナコールEX-614）。
エポキシ系架橋剤(*2)：グリセロールポリグリシジルエーテル：グリシジル基３個、エポキシ当量１４５（商品名：ディナコールEX-313）。
エポキシ系架橋剤(*3)：変性ビスフェノールＡ型エポキシ：グリシジル基２個、エポキシ当量９００。
＊４：デンプン固形分１００重量部使用。
＊５：ポリビニルアルコール固形分１００重量部使用。

Epoxy crosslinking agent (* 1): sorbitol polyglycidyl ether: 4 glycidyl groups, epoxy equivalent 166 (trade name: Dinacol EX-614).
Epoxy crosslinking agent (* 2): glycerol polyglycidyl ether: 3 glycidyl groups, epoxy equivalent 145 (trade name: Dinacol EX-313).
Epoxy crosslinking agent (* 3): Modified bisphenol A type epoxy: 2 glycidyl groups, epoxy equivalent 900.
* 4: Use 100 parts by weight of starch solids.
* 5: Use 100 parts by weight of polyvinyl alcohol solid content.

  As is clear from Examples 1 to 5, it was found that the polyester nonwoven fabric molded product using the nonwoven fabric reinforcing agent for asphalt roofing of the present invention is excellent in heat-resistant shape stability and strength characteristics.

Claims (5)

An aqueous dispersion (A) comprising a heat-reactive polyurethane resin having a number average molecular weight of 1,500 to 50,000 and starch are solids of the starch with respect to 100 parts by weight of the solid content of the aqueous dispersion (A). It is blended so that the amount is 50 to 300 parts by weight,
The aqueous dispersion (A) comprises a compound (B) having two or more active hydrogen atoms in the molecule, a compound (C) having at least one active hydrogen atom and a carboxyl group in the molecule, and an organic poly The heat-reactive polyurethane resin obtained by reacting isocyanate (D) and blocking agent (E) is dispersed in water,
The heat-reactive polyurethane resin contains 2 to 18% by weight of a blocked isocyanate group in terms of a recycled isocyanate group, and is a nonwoven fabric reinforcing agent for asphalt roofing. An aqueous dispersion (A) composed of a heat-reactive polyurethane resin having a number average molecular weight of 1,500 to 50,000, starch and an epoxy-based cross-linking agent (F) are 100 wt% of the solid content of the aqueous dispersion (A). The starch has a solid content of 50 to 300 parts by weight and the epoxy crosslinking agent (F) has a solid content of 10 to 80 parts by weight,
The aqueous dispersion (A) comprises a compound (B) having two or more active hydrogen atoms in the molecule, a compound (C) having at least one active hydrogen atom and a carboxyl group in the molecule, and an organic poly The heat-reactive polyurethane resin obtained by reacting isocyanate (D) and blocking agent (E) is dispersed in water,
The heat-reactive polyurethane resin contains 2 to 18% by weight of a blocked isocyanate group in terms of regenerated isocyanate group,
The epoxy-based crosslinking agent (F) has at least two glycidyl groups in the molecule, has an epoxy equivalent of 110 to 300 and a water content of 20% or more, and is a nonwoven fabric reinforcing agent for asphalt roofing . Chemical structural formulas (1-a, 1-, 1) introduced from the compound (B), the compound (C) and the organic polyisocyanate (D) in a solid content of 1,000 atomic weight of the aqueous dispersion (A). 3. The total number of aromatic rings and aliphatic rings represented by b, 1-c) or chemical structural formula (2-a, 2-b, 2-c) is 2 or more. Nonwoven reinforcement for asphalt roofing.

  The nonwoven fabric reinforcing agent for asphalt roofing according to any one of claims 1 to 3, wherein the organic polyisocyanate (D) is an aromatic polyisocyanate, and the blocking agent (E) is an oxime blocking agent.   The non-woven fabric reinforcing agent for asphalt roofing according to any one of claims 1 to 4, wherein the acid value of the carboxyl group in the solid content of the aqueous dispersion (A) is 10 to 60 mgKOH / g.