JPWO2007072802A1 - Water retention agent composition for mortar - Google Patents

Abstract

As a water retention agent composition for mortar, a water-soluble polyurethane containing two specific types of repeating units at a specific molar ratio is used in combination with water-soluble cellulose ethers. By using this water retention agent composition for mortar, it has high water retention, excellent workability such as lightening the operation of the bag, and sufficient shape retention without using asbestos (asbestos). The mortar which has can be obtained.

Description

  The present invention relates to a water retention agent composition for mortar. More specifically, plastering mortar, repair mortar, tile bonding (crimping) mortar, masonry mortar, pump-up mortar, spray mortar, wall mortar, wall finishing mortar, autoclave light weight concrete ( ALC) The present invention relates to a water retention agent composition for mortar that can be suitably used for a wide range of cement-based mortars such as joint filling mortars and floor finishing mortars, gypsum plaster, joint materials for plaster boards, plaster and the like. Especially, it is related with the water retention composition for mortar which can be used conveniently for the mortar (left plaster mortar) which needs the operation | work with a firewood.

  Various mortars composed of fine aggregates such as cement, sand, fibers, water, etc., cause a breathing phenomenon due to separation of water and other components, so that for the purpose of improving water retention (preventing breathing), etc. A water-soluble cellulose ether thickener has been added to increase the viscosity (see Patent Document 1).

  In addition, since it is necessary to maintain the shape immediately after molding, the mortar is required to have a certain degree of shape retention. In order to give shape retention to mortar, it is necessary for mortar to exhibit high thixotropy, but it is difficult to obtain sufficient shape retention simply by adding a water-soluble cellulose ether thickener. Met. For this reason, when using a water-soluble cellulose ether-based thickener, asbestos (asbestos) is often used together for the purpose of imparting thixotropy (see Patent Document 2). We were satisfied with formality at the same time.

  Further, Patent Document 3 discloses a plastering mortar admixture comprising a water-soluble polyurethane resin derived from a water-soluble polyoxyalkylene polyol and an organic polyisocyanate. However, the admixture for plastering mortar has a problem that the water retention is not sufficient, although the workability (releasability) is good.

Patent Documents 4 to 6 disclose extrusion aids for cement-based materials containing water-soluble polyurethane composed of comb-shaped diol and diisocyanate, but these publications disclose water retention agents for mortar. In particular, there is no description of a water retention agent for plastering mortar.
JP 58-015053 A Japanese Patent Laid-Open No. 01-282142 Japanese Patent Laid-Open No. 08-245250 JP-A-11-343328 JP 2000-297133 A US Pat. No. 6,646,093

  However, while these water-soluble cellulose ether thickeners give high water retention to the mortar, there has been a problem that the mortar becomes too viscous. For this reason, the work of the plasterer is poor and the operability of the bag is heavy, resulting in poor workability.

  In addition, recent environmental problems have revealed the harmfulness of asbestos (asbestos) to the human body, and the use of mortar that does not use asbestos (asbestos) has been desired.

  The present invention has been made in view of the problems as described above, has high water retention, is excellent in workability such as lightening the operation of the bag, and without using asbestos (asbestos). It aims at providing the water retention agent composition for mortar which can obtain the mortar which has sufficient shape retention property.

  In order to solve the above-mentioned problems, the present inventors have used a mortar that can be used in combination with water-soluble cellulose ethers, has both water retention and shape retention functions, and does not affect the operability of the bag in the plasterer. We have earnestly researched about compounds that can be obtained. As a result, it has been found that the above-mentioned problems can be solved by using a specific water-soluble polyurethane together with water-soluble cellulose ethers, and the present invention has been completed. More specifically, the present invention provides the following.

  (1) A water retention agent composition for mortar comprising a water-soluble polyurethane (A) and a water-soluble cellulose ether (B), wherein the water-soluble polyurethane (A) is represented by the following general formula (I) The unit (a) and the repeating unit (b) represented by the following general formula (II), the moles of the repeating unit (a) with respect to the total number of moles of the repeating unit (a) and the repeating unit (b) The ratio of the numbers is 0.5 to 0.99.

(Where
A represents a divalent linking group which is a dealcohol residue of polyoxyalkylene polyol HO-A-OH having hydroxyl groups at both ends;
B represents a divalent linking group that is a de-NCO residue of diisocyanate OCN-B-NCO. )

(Where
D represents a divalent linking group which is a dealcohol residue of a comb diol HO-D-OH having at least two hydrocarbon groups having 4 to 21 carbon atoms in the molecule;
B represents a divalent linking group that is a de-NCO residue of diisocyanate OCN-B-NCO. )
The mortar water-retaining agent composition (1) is a composition that serves as a water-retaining agent contained in the mortar composition. Here, “mortar” refers to materials for various building materials composed of fine aggregates such as cement and sand, fibers, water, etc., and “mortar” containing stone (gravel) is the so-called “concrete”. Will be called.

  Moreover, the water retention agent composition for mortar of the present invention is used for purposes other than “extrusion”. In general, the “extrusion molding composition” has a large molecular weight and is easy to mold by increasing the viscosity. On the other hand, in the case of a composition for so-called “mortar”, a water retention agent having a low molecular weight and a low viscosity is required from the viewpoint of workability such as wrinkles.

  The water retention agent composition for mortar (1) uses a water-soluble polyurethane (A) containing a comb diol as a constituent component. Since the hydrocarbon group of the comb-shaped diol has low polarity, in water, the interaction between the hydrocarbon groups causes a hydrophobic interaction between the polymer chains of the water-soluble polyurethane (A). For this reason, if a comb-shaped diol is used as a constituent component, the viscosity necessary for the water retention agent can be sufficiently obtained even with a water-soluble polyurethane having a relatively low molecular weight.

  Furthermore, the water retention agent composition for mortar (1) uses both water-soluble polyurethane (A) and water-soluble cellulose ethers (B). Therefore, while having high water retention derived from water-soluble cellulose ethers, without causing the problem of deterioration of workability such as heavy operation of the koji due to the blended amount of water-soluble cellulose ethers, and A mortar having sufficient shape retention can be obtained without using asbestos (asbestos).

  (2) The content of the water-soluble polyurethane resin (A) with respect to 100% by mass of the water retention agent composition for mortar is 1% by mass to 99% by mass, and the content of the water-soluble cellulose ethers (B) is The water retention agent composition for mortar according to (1), which is 1% by mass or more and 99% by mass or less.

  The water retention agent composition for mortar (2) has a specific range for the contents of the water-soluble polyurethane (A) and the water-soluble cellulose ethers (B). If each content is in this range, a water retention agent having excellent water retention and operability of the ridge can be obtained.

  (3) The water retaining composition for mortar according to (1) or (2), wherein the comb diol HO-D-OH is a comb diol represented by the following general formula (III) and / or the following general formula (IV): .

(Where
R ¹ is a hydrocarbon group having 1 to 20 carbon atoms or a nitrogen-containing hydrocarbon group,
R ² and R ³ may be the same or different and are hydrocarbon groups having 4 to 21 carbon atoms;
Here, at least part of the hydrogen atoms in R ¹ , R ² , and R ³ may be substituted with at least one atom selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Often,
Y and Y ′ may be the same or different and are any one selected from the group consisting of a hydrogen atom, a methyl group, and a CH ₂ Cl group,
Z and Z ′ may be the same or different and are any one selected from the group consisting of an oxygen atom, a sulfur atom, and a CH ₂ group,
n and n ′ may be the same or different,
n is an integer of 0 to 15 when Z is an oxygen atom, and 0 when Z is a sulfur atom or a CH ₂ group,
n ′ is an integer of 0 to 15 when Z ′ is an oxygen atom, and 0 when Z ′ is a sulfur atom or a CH ₂ group. )

(Where
R ⁴ is an alkylene group having 2 to 4 carbon atoms in total,
R ⁵ is a hydrocarbon group having 1 to 20 carbon atoms,
R ⁶ and R ⁷ may be the same or different and each is a hydrocarbon group having 4 to 21 carbon atoms;
Here, at least a part of the hydrogen atoms in R ⁴ , R ⁵ , and R ⁶ may be substituted with a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom,
S, S ′, and S ″ may be the same or different and are any one selected from the group consisting of a hydrogen atom, a methyl group, and a CH ₂ Cl group,
T and T ′ may be the same or different and are any one selected from the group consisting of an oxygen atom, a sulfur atom, and a CH ₂ group,
P and P ′ may be the same or different,
P is an integer of 0 to 15 when T is an oxygen atom, and 0 when T is a sulfur atom or a CH ₂ group,
P ′ is an integer of 0 to 15 when T ′ is an oxygen atom, and is 0 when T ′ is a sulfur atom or a CH ₂ group,
Q is an integer from 0 to 15. )
The water retention agent composition for mortar (3) uses a comb-shaped diol having a specific structure. By using a comb-shaped diol having a specific structure, sufficient water retention can be achieved with shorter kneading.

  (4) A mortar composition comprising the water retention agent composition for mortar according to any one of (1) to (3) and a hydraulic inorganic powder.

  (5) The water retention agent composition for mortar according to any one of (1) to (3), which is for plastering mortar.

  (6) The composition for mortar according to (4), which is for plastering mortar.

  However, the “left plaster mortar” described in (5) and (6) is a mortar formed by plastering work using a scissors or the like, specifically, a mortar for repair, a mortar for tile bonding (crimping), Masonry mortar, wall mortar, wall finishing mortar, autoclave light weight concrete (ALC) joint filling mortar, floor finishing mortar (self-leveling material, etc.).

  (7) A plastering method using the mortar composition according to (4) or (6).

  “Plastering work” means painting mortar on the surface of various base materials such as building structures such as walls, ceilings, and rooftops.

  According to the water retention agent composition for mortar of the present invention, it has high water retention, does not cause a problem of deterioration in workability such as heavy maneuvering, and does not use asbestos (asbestos). In both cases, a mortar having sufficient shape retention can be obtained.

<Water retention composition for mortar>
The water retention agent composition for mortar of the present invention is a composition containing water-soluble polyurethane (A) and water-soluble cellulose ethers (B).

The compounding ratio of the water-soluble polyurethane (A) and the water-soluble cellulose ethers (B) in the water retention agent composition for mortar is not particularly limited. Preferably, the content of the water-soluble polyurethane (A) with respect to 100% by mass of the water retention agent composition for mortar is 1 to 99% by mass, and the content of the water-soluble cellulose ethers (B) is 99 to 1% by weight. More preferably, water-soluble polyurethane (A) 10 to 90 wt%, water-soluble cellulose ethers (B) is in the range of 90 to 10 wt%, more preferably, water-soluble polyurethane (A) 15 to 70 wt%, water-soluble cellulose ethers (B) is in the range of 85 to 30 wt%. By using the water-soluble polyurethane (A) and the water-soluble cellulose ethers (B) in the above range, a mortar composition having excellent water retention can be obtained. In particular, the composition for mortar containing 15 to 70% by mass of the water-soluble polyurethane (A) and 85 to 30% by mass of the water-soluble cellulose ethers (B) is also excellent in the glazing workability.

[Water-soluble polyurethane (A)]
The water-soluble polyurethane (A) used in the present invention comprises a repeating unit (a) represented by the following general formula (I) and a repeating unit (b) represented by the following general formula (II) as essential constituent units. To do. As long as the repeating unit (a) and the repeating unit (b) are included, a small amount of any other repeating unit may be included.

(Where
A represents a divalent linking group which is a dealcohol residue of polyoxyalkylene polyol HO-A-OH having hydroxyl groups at both ends;
B represents a divalent linking group that is a de-NCO residue of diisocyanate OCN-B-NCO. )

(Where
D represents a divalent linking group which is a dealcohol residue of a comb diol HO-D-OH having at least two monovalent hydrocarbon groups having 4 to 21 carbon atoms in the molecule;
B represents a divalent linking group that is a de-NCO residue of diisocyanate OCN-B-NCO. )
The ratio of the number of moles of the repeating unit (a) to the total number of moles of the repeating unit (a) and the repeating unit (b) is usually 0.5 or more and 0.99 or less, preferably 0.70 or more. It is 0.99 or less, More preferably, it is 0.80 or more and 0.90 or less.
[Polyoxyalkylene polyol: HO-A-OH]
Although it does not specifically limit as polyoxyalkylene polyol HO-A-OH which has a hydroxyl group in both the terminals used as the constituent material of the repeating unit (a) represented by the said general formula (I), It is carbon number. A polyoxyalkylene polyol having 2 to 6 alkylene groups can be preferably used.

  More specifically, polyethylene glycol (PEG), polypropylene glycol (PPG), a copolymer of polyethylene oxide and polypropylene oxide, polytetramethylene ether glycol (PTMEG), polyhexamethylene ether glycol and the like can be preferably used. . Particularly preferably, polyethylene glycol (PEG) is used.

  The number average molecular weight (Mn) of the polyoxyalkylene polyol HO-A-OH having hydroxyl groups at both ends, which is a constituent material of the repeating unit (a), is preferably 400 or more and 100,000 or less, more preferably 400 or more and 20 or more. , 000 or less, more preferably in the range of 900 or more and 9,000 or less. If the number average molecular weight is 400 or more, a water-soluble polyurethane (A) having sufficient characteristics as a water retention agent can be obtained. On the other hand, if the number average molecular weight is 100,000 or less, a sufficient polymerization reaction can be performed.

  The polyoxyalkylene polyol HO-A-OH having a hydroxyl group at both ends, which is a constituent material of the repeating unit (a), is not only a single use, but also a combination of two or more polyoxyalkylene polyols. May be used. For example, polyethylene glycol and polypropylene glycol or polytetramethylene ether glycol can be used in combination. In order to have solubility in water, it is more preferable to use 70% of polyethylene glycol (PEG).

Moreover, if it is up to 20% by mass of the total glycols, low molecular weight glycols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tetramethylene glycol, hexamethylene glycol and the like are used in combination with the above polyoxyalkylene polyols. May be.
[Diisocyanate: OCN-B-NCO]
The diisocyanate OCN-B-NCO that is a constituent material of the repeating units (a) and (b) represented by the general formula (I) and the general formula (II) is not particularly limited. Examples thereof include a diisocyanate compound selected from the group consisting of chain aliphatic diisocyanates, cycloaliphatic diisocyanates, and aromatic diisocyanates. Among these, it is preferable to use diisocyanates having 3 to 18 carbon atoms (including carbon atoms of the NCO group).

  The chain aliphatic diisocyanates are polyisocyanate compounds having a structure in which NCO groups are connected by a linear or branched alkylene group. Specific examples include methylene diisocyanate, ethylene diisocyanate, trimethylene diisocyanate, 1-methylethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, 2-methylbutane-1,4-di. Isocyanate, hexamethylene diisocyanate (HMDI), heptamethylene diisocyanate, 2,2′-dimethylpentane-1,5-diisocyanate, lysine diisocyanate methyl ester (LDI), octamethylene diisocyanate, 2,5-dimethylhexane-1,6-diisocyanate, 2,2,4-trimethylpentane-1,5-diisocyanate, nonamethyl diisocyanate, 2,4,4-trimethylhexane-1,6 -Diisocyanate, decamethylene diisocyanate Anato, undecamethylene diisocyanate, dodecamethylene diisocyanate, tridecamethylene diisocyanate, tetradecamethylene diisocyanate, pentadecamethylene diisocyanate, hexadecamethylene diisocyanate, trimethylhexamethylene diisocyanate, etc. Isocyanates.

  Cycloaliphatic diisocyanates are polyisocyanate compounds having a structure in which NCO groups are connected by an alkylene group having a cyclic structure. Specific examples include cyclohexane-1,2-diisocyanate, cyclohexane-1,3-diisocyanate, cyclohexane-1,4-diisocyanate, 1-methylcyclohexane-2,4-diisocyanate, 1- Methylcyclohexane-2,6-diisocyanate, 1-ethylcyclohexane-2,4-diisocyanate, 4,5-dimethylcyclohexane-1,3-diisocyanate, 1,2-dimethylcyclohexane-ω, ω ′ -Diisocyanate, 1,4-dimethylcyclohexane-ω, ω'-diisocyanate, isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethylmethane-4,4'- Diisocyanate, dicyclohexyldimethylmethane-4,4′-diisocyanate Anato, 2,2′-dimethyldicyclohexylmethane-4,4′-diisocyanate, 3,3′-dimethyldicyclohexylmethane-4,4′-diisocyanate, 4,4′-methylene-bis (isocyanatocyclohexane ), Isopropylidenebis (4-cyclohexylisocyanate) (IPCI), 1,3-bis (isocyanatomethyl) cyclohexane, hydrogenated tolylene diisocyanate (H-TDI), hydrogenated 4,4′-diphenylmethane diisocyanate Examples thereof include diisocyanates such as nate (H-MDI), hydrogenated xylylene diisocyanate (H-XDI), norbornane diisocyanate methyl (NBDI).

Aromatic diisocyanates are polyisocyanates having a structure in which NCO groups are connected by aromatic groups such as phenylene groups, alkyl-substituted phenylene groups, and aralkylene groups, or hydrocarbon groups containing aromatic groups. It is a nate compound. Specific examples include 1,3- and 1,4-phenylene diisocyanate, 1-methyl-2,4-phenylene diisocyanate (2,4-TDI), 1-methyl-2,6-phenylene diisocyanate. Nert (2,6-TDI), 1-methyl-2,5-phenylene diisocyanate, 1-methyl-3,5-phenylene diisocyanate, 1-ethyl-2,4-phenylene diisocyanate, 1- Isopropyl-2,4-phenylene diisocyanate, 1,3-dimethyl-2,4-phenylene diisocyanate, 1,3-dimethyl-4,6-phenylene diisocyanate, 1,4-dimethyl-2,5 -Phenylene diisocyanate, m-xylene diisocyanate, diethylbenzene diisocyanate, diisopropylbenzene diisocyanate, 1-methylene 3,5-diethylbenzene-2,4-diisocyanate, 3-methyl-1,5-diethylbenzene-2,4-diisocyanate, 1,3,5-triethylbenzene-2,4-diisocyanate , Naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 1-methylnaphthalene-1,5-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-2,7- Diisocyanate, 1,1-dinaphthyl-2,2′-diisocyanate, biphenyl-2,4′-diisocyanate, biphenyl-4,4′-diisocyanate, 1,3-bis (1-isocyanate -1-methylethyl) benzene, 3,3′-dimethylbiphenyl-4,4′-diisocyanate, diphenylmethane-4,4′-diisocyanate (M I), diphenylmethane-2,2'-diisocyanate, diphenylmethane-2,4'-diisocyanate, diisocyanate and the like, such as xylylene diisocyanate (XDI).
[Comb diol: HO-D-OH]
The comb diol HO-D-OH, which is a constituent material of the repeating unit (b) represented by the general formula (II), has at least two monovalent hydrocarbon groups having 4 to 21 carbon atoms in the molecule. It is a diol having. Here, a plurality of monovalent hydrocarbon groups are grafted as side chains on the molecular skeleton of diols, and from this shape, they are called “comb diols”.

  The monovalent hydrocarbon group having 4 to 21 carbon atoms is not particularly limited, and examples thereof include an alkyl group, an alkenyl group, an aralkyl group, and an aryl group.

  Further, in the comb-shaped diol HO-D-OH, the graft position of the monovalent hydrocarbon group having 4 to 21 carbon atoms may be directly grafted to the molecular skeleton of the diol, or may be a methylene group or an ether group. In addition, it may be bonded to the molecular skeleton via a thioether group, a polyether group or the like.

  The molecular skeleton of the comb-shaped diol HO-D-OH may be composed only of hydrocarbons, but an ether group (—O—), a polyether group, a tertiary amino group (—N (R) —), etc. A diol having the polar group in the molecular skeleton is also preferably used in the present invention.

  The method for producing such a comb diol is not particularly limited, and can be obtained by a known method. Known methods include, for example, methods described in JP-A Nos. 11-343328 and 12-297133, and methods described in JP-A No. 2004-169011.

  Examples of the comb diol HO-D-OH preferably used in the present invention include comb diols represented by the following general formula (III) and the following general formula (IV). The comb diols represented by the following general formula (III) and general formula (IV) may be used alone or in combination of two or more. For example, when using multiple types of comb diols represented by general formula (III), when using multiple types of comb diols represented by general formula (IV), they are represented by general formula (III). The comb-type diol may be mixed with the comb-type diol represented by the general formula (IV).

(Where
R ¹ is a hydrocarbon group or nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms, more preferably 4 to 12 carbon atoms,
R ² and R ³ may be the same or different and are hydrocarbon groups having 4 to 21 carbon atoms, more preferably 4 to 12 carbon atoms;
Here, at least part of the hydrogen atoms in R ¹ , R ² , and R ³ may be substituted with at least one atom selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Often,
Y and Y ′ may be the same or different and are any one selected from the group consisting of a hydrogen atom, a methyl group, and a CH ₂ Cl group,
Z and Z ′ may be the same or different and are any one selected from the group consisting of an oxygen atom, a sulfur atom, and a CH ₂ group,
n and n ′ may be the same or different,
n is an integer of 0 to 15 when Z is an oxygen atom, and 0 when Z is a sulfur atom or a CH ₂ group,
n ′ is an integer of 0 to 15 when Z ′ is an oxygen atom, and 0 when Z ′ is a sulfur atom or a CH ₂ group. )

(Where
R ⁴ is an alkylene group having 2 to 4 carbon atoms in total,
R ⁵ is a hydrocarbon group having 1 to 20 carbon atoms, more preferably 4 to 12 carbon atoms,
R ⁶ and R ⁷ may be the same or different and are hydrocarbon groups having 4 to 21 carbon atoms, more preferably 4 to 12 carbon atoms;
Here, at least a part of the hydrogen atoms in R ⁴ , R ⁵ , and R ⁶ may be substituted with a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom,
S, S ′, and S ″ may be the same or different and are any one selected from the group consisting of a hydrogen atom, a methyl group, and a CH ₂ Cl group,
T and T ′ may be the same or different and are any one selected from the group consisting of an oxygen atom, a sulfur atom, and a CH ₂ group,
P and P ′ may be the same or different,
P is an integer of 0 to 15 when T is an oxygen atom, and 0 when T is a sulfur atom or a CH ₂ group,
P ′ is an integer of 0 to 15 when T ′ is an oxygen atom, and is 0 when T ′ is a sulfur atom or a CH ₂ group,
Q is an integer from 0 to 15. )
[Method for producing water-soluble polyurethane (A)]
The manufacturing method of water-soluble polyurethane (A) used for this invention is not specifically limited, A well-known arbitrary method is employable. As a method for producing the water-soluble polyurethane (A), for example, the method described in JP-A Nos. 11-343328 and 12-297133, or the method described in JP-A No. 2004-169011 is used. be able to. Among them, the method described in JP-A No. 2004-169011 is particularly excellent in that the particle diameter of the obtained polyurethane resin is uniform and the average particle diameter can be easily reduced to 200 μm or less.
[Physical properties of water-soluble polyurethane (A)]
The viscosity of the water-soluble polyurethane (A) used in the present invention is a B-type viscometer (up to 100,000 mPa · s is 6 rpm using a BL-type viscometer, and higher viscosity is 4 rpm using a BH-type viscometer). The viscosity of the 2% aqueous solution measured at 20 ° C. is preferably 10 mPa · s to 300,000 mPa · s, more preferably 100 mPa · s to 200,000 mPa · s, particularly preferably 1000 mPa · s to 200,000 mPa. -It is appropriate to be in the range of s or less. In the present invention, if the viscosity of the 2% aqueous solution is 10 mPa · s or more, water retention can be improved. Moreover, if the viscosity of 2% aqueous solution is 300,000 mPa * s or less, the fall of workability | operativity in the operation of a basket can be prevented.

  In addition, the particle diameter of the water-soluble polyurethane (A) powder used in the present invention is preferably finer from the viewpoint of easily making a mortar. However, since it is difficult to handle if it is too fine, the average particle diameter is preferably 10 μm or more and 300 μm or less, more preferably about 50 μm or more and 200 μm or less.

[Water-soluble cellulose ethers (B)]
The water-soluble cellulose ethers (B) used in the present invention are not particularly limited, and known water-soluble cellulose ethers can be used as a mortar thickener.

  Specific examples of the water-soluble cellulose ethers (B) used in the present invention include, for example, methyl cellulose (MC), methyl hydroxyethyl cellulose (MHEC), methyl hydroxypropyl cellulose (MHPC), hydroxyethyl cellulose (HEC), and ethyl hydroxyethyl. Cellulose (EHEC) etc. are mentioned. Commercially available water-soluble cellulose ethers can also be used. Examples of commercially available products include cellulene manufactured by Daicel Finechem, Metrols and hi-Metroses manufactured by Shin-Etsu Chemical, Marporose manufactured by Matsumoto Yushi Seiyaku, and Dow Methocel made by Akzo Nobel, Vermocol made by Akzo Nobel, Aqualon made by Hercules, and the like.

[Other ingredients]
The water retention agent composition for mortar according to the present invention includes a surfactant, a dispersant (water reducing agent), an air entraining agent (AE agent), an antifoaming agent, an anti-blocking agent, and a shrinkage as long as the object of the present invention is not impaired. You may mix | blend well-known additives, such as a reducing agent.

  In addition, water-soluble polymers such as acrylic polymers, polyvinyl alcohol, polyethylene glycol (PEG), polyethylene oxide (PEO), guar gum, xanthan gum, welan gum and the like may be used in combination with the water retention agent composition for mortar of the present invention. it can.

<Mortar composition>
The mortar composition of the present invention comprises the mortar water retention composition of the present invention and a hydraulic inorganic powder as essential components. In the present invention, the content of the water retention agent composition for mortar of the present invention is 0.01% by mass to 1% by mass with respect to 100% by mass of the mortar composition, hydraulic inorganic powder and fine bones such as sand. The combined content of the materials is preferably 99% by mass or more and 99.99% by mass or less.

  Here, the ratio between the hydraulic inorganic powder and the fine aggregate varies depending on the use of the mortar obtained thereafter, but usually the fine aggregate is 0.5 to 5 times the hydraulic inorganic powder. Mix to the extent.

  The hydraulic inorganic powder used in the mortar composition of the present invention is not particularly limited, and examples thereof include various portland cements, alumina cements, blast furnace cements, calcium silicates, and the like. Further, the fine aggregate used in the present invention is not particularly limited. Examples include hollow polymer particles.

  The mortar composition of the present invention comprises, as other optional components, various water reducing agents, re-emulsified emulsion resin powders, antifoaming agents, surfactants, shrinkage reducing agents, curing accelerators, curing retarders, various fibers (lock Wool, glass fiber, carbon fiber, cellulose fiber, pulp, various synthetic resin fibers) and the like.

  In addition, the composition for mortar of this invention can be used for construction as a mortar by adding a suitable quantity of water suitably according to various mortar uses. In addition, the mortar using the mortar water-retaining composition of the present invention is a mortar that is soft enough to allow plastering using a ridge, unlike a mortar for extrusion molding.

〔Example〕
EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to these Examples.

<Synthesis of water-soluble polyurethane PU-1>
[Synthesis of Comb Diol-1]
A magnetic stirrer, a thermometer, and a dropping funnel were placed in a 500 mL round bottom flask, charged with 64.6 g of 2-ethylhexylamine (manufactured by Koei Chemical Co., Ltd.), and the inside of the flask was replaced with nitrogen. Subsequently, the flask was heated to 90 ° C. in an oil bath, and while stirring, 190.0 g of 2-ethylhexyl glycidyl ether (manufactured by Asahi Denka Co., Ltd., trade name: Adekaglycyl ED518S, epoxy value: 186) was added using a dropping funnel. It was dripped over 40 minutes. After completion of dropping, the temperature of the oil bath was raised to 120 ° C., and the flask was heated for 10 hours. Subsequently, the temperature of the oil bath was raised to 150 ° C., and a small amount of unreacted substances were distilled off under reduced pressure using a vacuum pump at a vacuum degree of 3 mmHg. Thereby, comb-shaped diol-1 (average molecular weight from OH value: 510) in which 2-ethylhexyl glycidyl ether was added at a ratio of 2 moles to 1 mole of 2-ethylhexylamine was obtained in a yield of 95%.

[Synthesis of Prepolymer-1]
20 g of the comb-shaped diol-1 obtained above and 45.5 g of hexamethylene diisocyanate (HDI) were added to a 100 mL glass flask. The flask was heated to 80 ° C. for 8 hours to obtain Prepolymer-1.

[Synthesis of water-soluble polyurethane PU-1]
Synthesis was performed according to the method described in Example 8 of JP-A No. 2004-169011.

  A 2000 mL glass separable flask was charged with 500 g of commercially available polyethylene glycol (manufactured by Sanyo Chemical Co., Ltd., trade name: PEG # 6000, number average molecular weight: 8,630) and melted at 150 ° C. under a nitrogen seal. While stirring this, it was dried under reduced pressure (3 mmHg) for 3 hours. After drying, the temperature was lowered to 70 ° C., and the flask was filled with 1 atm of nitrogen. Subsequently, 16.04 g of the prepolymer-1 obtained above and 1000 ppm of di-ter-butylhydroxytoluene (BHT) as an antioxidant were added and stirred, and then 350 g of isooctane (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent was added. Then, 1.5 g of a dispersant was added and dispersed with a disper. While stirring the flask, 0.05 g of dibutyltin dilaurate (DBTDL) was added as a catalyst and reacted at 90 ° C. for 6 hours. Subsequently, the temperature was lowered to 40 ° C., the product was taken out from the flask, and filtered and dried to obtain a water-soluble polyurethane resin (PU-1). The average particle diameter of the obtained resin powder was 100 μm, and the viscosity of a 2% aqueous solution at 20 ° C. was 4,200 mPa · s (BL viscometer, 6 rpm).

<Synthesis of water-soluble polyurethane PU-2>
[Synthesis of Comb Diol-2]
A magnetic stirrer, a thermometer, and a dropping funnel were placed in a 500 mL round bottom flask, charged with 64.6 g of 3-lauryloxypropylamine (manufactured by Koei Chemical Co., Ltd.), and the inside of the flask was replaced with nitrogen. Subsequently, the flask was heated to 90 ° C. in an oil bath, and while stirring, 100.7 g of 2-ethylhexyl glycidyl ether (manufactured by Asahi Denka Co., Ltd., trade name: Adekaglycylol ED518S, epoxy value: 186) was added using a dropping funnel. It was dripped over 40 minutes. After completion of dropping, the temperature of the oil bath was raised to 120 ° C., and the flask was heated for 10 hours. Subsequently, the temperature of the oil bath was raised to 150 ° C., and a small amount of unreacted material was distilled off under reduced pressure using a vacuum pump at a degree of vacuum of 3 mmHg. Thereby, comb-shaped diol-2 (average molecular weight from OH value: 630) in which 2-ethylhexyl glycidyl ether was added at a ratio of 2 mol to 1 mol of 3-lauryloxypropylamine was obtained in a yield of 95%.

[Synthesis of Prepolymer-2]
20 g of the comb-shaped diol-2 obtained above and 44 g of hexamethylene diisocyanate (HDI) were added to a 100 mL glass flask. The flask was heated to 80 ° C. for 6 hours to obtain Prepolymer-2.

[Synthesis of water-soluble polyurethane PU-2]
Synthesis was performed according to the method described in Example 8 of JP-A No. 2004-169011.

  A 2000 mL glass separable flask was charged with 500 g of commercially available polyethylene glycol (manufactured by Sanyo Chemical Co., Ltd., trade name: PEG # 6000, number average molecular weight: 8,630) and melted at 150 ° C. under a nitrogen seal. While stirring this, it was dried under reduced pressure (3 mmHg) for 3 hours. After drying, the temperature was lowered to 70 ° C., and the flask was filled with 1 atm of nitrogen. Subsequently, 16.0 g of the prepolymer-2 obtained above and 1000 ppm of di-ter-butylhydroxytoluene (BHT) as an antioxidant were added and stirred, and then 350 g of isooctane (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent was added. Then, 1.5 g of a dispersant was added and dispersed with a disper. While stirring the flask, 0.05 g of dibutyltin dilaurate (DBTDL) was added as a catalyst and reacted at 90 ° C. for 6 hours. Subsequently, the temperature was lowered to 40 ° C., the product was taken out from the flask, filtered and dried to obtain a water-soluble polyurethane resin (PU-2). The average particle diameter of the obtained resin powder was 120 μm, and the viscosity of a 2% aqueous solution at 20 ° C. was 200,000 mPa · s (BH viscometer, 4 rpm).

[Synthesis of water-soluble polyurethane PU-3]
(Synthesis example of water-soluble polyurethane not containing comb diol skeleton)
It synthesized according to the synthesis example of the water-soluble polyurethane resin PU-1. However, HDI was used instead of prepolymer-1.

  A 2000 mL glass separable flask was charged with 500 g of commercially available polyethylene glycol (manufactured by Sanyo Chemical Co., Ltd., trade name: PEG # 6000, number average molecular weight: 8,630) and melted at 150 ° C. under a nitrogen seal. While stirring this, it was dried under reduced pressure (3 mmHg) for 3 hours. After drying, the temperature was lowered to 70 ° C., and the flask was filled with 1 atm of nitrogen. Subsequently, 9.5 g of HDI, 1000 ppm of di-tert-butylhydroxytoluene (BHT) as an antioxidant were added and stirred, and then 350 g of isooctane (manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent and 1.5 g of a dispersant were added. And dispersed with a disper. While stirring the flask, 0.05 g of dibutyltin dilaurate (DBTDL) was added as a catalyst and reacted at 90 ° C. for 6 hours. Subsequently, the temperature was lowered to 40 ° C., the product was taken out from the flask, filtered and dried to obtain a water-soluble polyurethane (PU-3). The average particle diameter of the obtained resin powder was 100 μm, and the viscosity of a 2% aqueous solution at 20 ° C. was 23 mPa · s (B-type viscometer, 6 rpm).

<Example 1>
[Preparation of mortar]
Normal portland cement (C), Toyoura sand (S), water-soluble cellulose ether (MC) (manufactured by Daicel Finechem, trade name: Cellbrene), and water-soluble polyurethane (PU-1) obtained above The test mortar was obtained by mixing for 1 minute with the formulation described in Table 1, then adding tap water (W) in the formulation amount described in Table 1 and kneading for 3 minutes.

<Evaluation>
[Water retention evaluation]
The obtained test mortar was subjected to water retention evaluation in accordance with the water retention test method for tile bonding mortars defined by the Urban Regeneration Organization. Specifically, a brass ring mold having an inner diameter of 50 mm, a height of 10 mm, and a thickness of 3 mm is placed on a filter paper (5A filter paper for chemical analysis) on a glass plate, and the mortar kneaded in the ring mold is filled with the glass plate. And placed upside down in a 20 ° C incubator. Take out from the incubator after 1 hour, measure the spread of moisture in the direction where the spread of moisture exuded on the filter paper is the maximum and the direction perpendicular to the direction, and measure the average value (1/2 of the sum) as Z (Mm) and the water retention rate was calculated by the following formula. The calculation results are shown in Table 1.

Water retention rate (%) = 50 ÷ Z × 100
In addition, since the standard of the water retention rate of tile mortar determined by the Urban Revitalization Organization is 80% or more and 95% or less, the water retention rate was evaluated according to the following criteria. The evaluation results are shown in Table 1.

○: Water retention rate of 80% to 95% ×: Water retention rate of less than 80% [Evaluation of workability]
As the workability evaluation, the workability when mortar was applied to a flat plate using a scissors was evaluated according to the following criteria. The evaluation results are shown in Table 1.

○: The wrinkle can be operated lightly. Δ: The wrinkle is felt slightly heavy. ×: The mortar is sticky and the wrinkle is felt considerably heavy <Examples 2 to 3>
Using the water-soluble polyurethane (PU-1) obtained above, a test mortar was obtained in the same manner as in Example 1 according to the formulation described in Table 1. Using the obtained test mortar, water retention evaluation and workability evaluation were performed in the same manner as in Example 1. The evaluation results are shown in Table 1.

<Examples 4 and 5>
Using the water-soluble polyurethane (PU-2) obtained above, a test mortar was obtained in the same manner as in Example 1 according to the formulation described in Table 1. Using the obtained test mortar, water retention evaluation and workability evaluation were performed in the same manner as in Example 1. The evaluation results are shown in Table 1.

<Comparative Example 1>
A test mortar was obtained in the same manner as in Example 1 by using the formulation described in Table 1 without using polyurethane. Using the obtained test mortar, water retention evaluation and workability evaluation were performed in the same manner as in Example 1. The evaluation results are shown in Table 1.

<Comparative Examples 2-3>
Using the water-soluble polyurethane (PU-1) obtained above, a test mortar was obtained in the same manner as in Example 1 by using the formulation described in Table 1 without using a water-soluble cellulose ether (MC). Using the obtained test mortar, water retention evaluation and workability evaluation were performed in the same manner as in Example 1. The evaluation results are shown in Table 1.

<Comparative Examples 4 and 5>
Using the water-soluble polyurethane (PU-3) not containing the comb-shaped diol skeleton obtained above, a test mortar was obtained in the same manner as in Example 1 according to the formulation described in Table 1. Using the obtained test mortar, water retention evaluation and workability evaluation were performed in the same manner as in Example 1. The evaluation results are shown in Table 1.

<Summary>
As shown in Table 1, by using a mixture of water-soluble polyurethane (A) and water-soluble cellulose ether (B), while maintaining water retention, compared to the case of water-soluble cellulose ether (B) alone Workability has been improved. Moreover, it turned out that sufficient effect is acquired with a small addition amount rather than the case of single use of water-soluble polyurethane (A) (Comparative Examples 2-3). Further, it was found that when water-soluble polyurethane containing no comb-shaped diol was used (Comparative Examples 4 and 5), it was difficult to obtain sufficient water retention.

  The present invention includes plastering mortar, repair mortar, tile bonding (crimping) mortar, masonry mortar, pump-up mortar, spraying mortar, foundation mortar, finishing mortar, autoclave light weight concrete (ALC) filling A wide range of cement-based mortars such as mortar for flooring and mortar for floor finishing (self-leveling material), gypsum plaster, joint treatment material for gypsum board, and water retention agent for plaster. Among them, plastering mortars that need to work with firewood (plamber mortar, repair mortar, tile bonding (crimping) mortar, masonry mortar, wall mortar, wall finishing mortar, autoclave light weight concrete ( ALC) Particularly suitable for joint filling mortar, floor finishing mortar (self-leveling material, etc.).

Claims (7)

A water retention agent composition for mortar comprising water-soluble polyurethane (A) and water-soluble cellulose ethers (B),
The water-soluble polyurethane (A) includes a repeating unit (a) represented by the following general formula (I) and a repeating unit (b) represented by the following general formula (II):
The ratio of the number of moles of the repeating unit (a) to the total number of moles of the repeating unit (a) and the repeating unit (b) is 0.5 or more and 0.99 or less.
(Where
A represents a divalent linking group which is a dealcohol residue of polyoxyalkylene polyol HO-A-OH having hydroxyl groups at both ends;
B represents a divalent linking group that is a de-NCO residue of diisocyanate OCN-B-NCO. )
(Where
D represents a divalent linking group which is a dealcohol residue of a comb diol HO-D-OH having at least two monovalent hydrocarbon groups having 4 to 21 carbon atoms in the molecule;
B represents a divalent linking group that is a de-NCO residue of diisocyanate OCN-B-NCO. )   The content of the water-soluble polyurethane (A) with respect to 100% by mass of the water retention agent composition for mortar is 1% by mass to 99% by mass, and the content of the water-soluble cellulose ethers (B) is 1% by mass or more. The water-retaining agent composition for mortar according to claim 1, which is 99% by mass or less. The water retention agent composition for mortar according to claim 1 or 2, wherein the comb diol HO-D-OH is a comb diol represented by the following general formula (III) and / or the following general formula (IV).
(Where
R ¹ is a hydrocarbon group having 1 to 20 carbon atoms or a nitrogen-containing hydrocarbon group,
R ² and R ³ may be the same or different and are hydrocarbon groups having 4 to 21 carbon atoms;
Here, at least part of the hydrogen atoms in R ¹ , R ² , and R ³ may be substituted with at least one atom selected from the group consisting of a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Often,
Y and Y ′ may be the same or different and are any one selected from the group consisting of a hydrogen atom, a methyl group, and a CH ₂ Cl group,
Z and Z ′ may be the same or different and are any one selected from the group consisting of an oxygen atom, a sulfur atom, and a CH ₂ group,
n and n ′ may be the same or different,
n is an integer of 0 to 15 when Z is an oxygen atom, and 0 when Z is a sulfur atom or a CH ₂ group,
n ′ is an integer of 0 to 15 when Z ′ is an oxygen atom, and 0 when Z ′ is a sulfur atom or a CH ₂ group. )
(Where
R ⁴ is an alkylene group having 2 to 4 carbon atoms in total,
R ⁵ is a hydrocarbon group having 1 to 20 carbon atoms,
R ⁶ and R ⁷ may be the same or different and each is a hydrocarbon group having 4 to 21 carbon atoms;
Here, at least a part of the hydrogen atoms in R ⁴ , R ⁵ , and R ⁶ may be substituted with a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom,
S, S ′, and S ″ may be the same or different and are any one selected from the group consisting of a hydrogen atom, a methyl group, and a CH ₂ Cl group,
T and T ′ may be the same or different and are any one selected from the group consisting of an oxygen atom, a sulfur atom, and a CH ₂ group,
P and P ′ may be the same or different,
P is an integer of 0 to 15 when T is an oxygen atom, and 0 when T is a sulfur atom or a CH ₂ group,
P ′ is an integer of 0 to 15 when T ′ is an oxygen atom, and is 0 when T ′ is a sulfur atom or a CH ₂ group,
Q is an integer from 0 to 15. )   A mortar composition comprising the water retention agent composition for mortar according to any one of claims 1 to 3 and a hydraulic inorganic powder.   The water retention agent composition for mortar according to any one of claims 1 to 3, which is for plastering mortar.   The mortar composition according to claim 4, which is used for plastering mortar.   A plastering method using the mortar composition according to claim 4.