JPH11320522A - Hardening retarding sheet for cement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more deepen a depth for retarding hardening of a cement composition by roughening the surface of a layer, which is made of a resin composition having a hardening retarding property for a cement and the like and formed in a retarding sheet of hardening of the cement, without changing the composition of the resin composition. SOLUTION: In a hardening retarding sheet for a cement equipped with a layer made of the composition of a resin having the retarding property of hardening of the cement in itself or a resin composition mixed with a cement hardening retarder, the surface of the layer is roughened so as to have a degree of roughness larger than a certain fixed value. In this case, the ruggedness of unevenness is measured by setting the average of the ratio between the length of the ridgeline and the measured length of an undulation is set to be 1.15 or more. Further, the unevenness is formed by mixing granular matters in either one of the above-mentioned resin compositions. Furthermore, as the resin having the retarding property of hardening of the cement in itself, a saturated polyester resin or the like is employed. As a result, the hardening retarding depth of the cement composition is made deeper and the recognition of the front and rear surfaces of a sheet having both transparent from and rear layers can be done easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a sheet useful for delaying the hardening of the surface of a curable composition containing cement. More specifically, it inhibits or delays the curing of the surface layer of a concrete molded product, a building, or a building, and the uncured portion is washed away with water or the like (hereinafter, also referred to as washing out), and the surface of the concrete product is provided with an aggregate. More particularly, the present invention relates to a method useful for adjusting the washing depth of the sheet, and a sheet useful for a method of exposing the surface or forming irregularities.

[0002] In the present specification, unless otherwise specified, "cement" means an inorganic substance which shows curability when mixed with water, and is used to include air-hardened cement, hydraulic cement and the like. Furthermore, the curable composition containing cement includes a cement paste, a mortar composition, a concrete composition, and the like, and these may be simply referred to as “inorganic curable composition” or “cement composition”. . In this specification, the term “sheet” refers to a two-dimensional structure regardless of thickness, material, or configuration, and is used to include a film.

[0003]

2. Description of the Related Art Processing the surface of a concrete product,
In order to form a pattern on the surface, a setting retarder for a cement composition (hereinafter referred to as a cement setting retarder or simply a setting retarder) is used. For example, a concrete wash-out flat plate is a mold to which a cement setting retarder is applied, or a mold in which paper impregnated with the setting retarder is laid, and after pouring the cosmetic cement composition, for backing. It is manufactured by casting and curing a cement composition, and after the cement composition has hardened, it is released from the mold and the concrete surface to which the hardening retarder has adhered is washed out.

JP-A-5-38711 and JP-A-5-38711
Japanese Patent No. 50411 discloses that a mixture containing a super retarder, a tackifier, a bulking agent, and a white pigment is adhered to a mold, mortar or concrete is poured, cured and demolded, and a cement product is obtained. There is disclosed a method of washing out the aggregate on the contact surface with a mold and finishing the surface of a cement product.

[0005] Also, as a method of forming an uneven pattern on the surface of a concrete product, a method using a cement setting retarder, and a method using a paper pattern impregnated or coated with the cement setting retarder are known. For example, JP-A-63-2
Japanese Patent No. 16703 discloses a process of cutting the pattern to create a cutting pattern corresponding to a pattern such as a predetermined character or figure, a step of bonding the cutting pattern to a predetermined portion of the inner surface of the form, and a step of forming a mortar in the form. A method of forming predetermined irregularities on the surface of a concrete product through a process of casting and curing the composition, a process of disassembling the formwork to take out a concrete product, and a process of washing out a pattern portion of the concrete product is disclosed. Have been. JP-A-61-202803 discloses a method in which a tile or the like is attached to paper coated with the cement setting retarder, set in a mold, and washed out in the same manner as described above.

In the method of using a cement setting retarder in place of a pattern, a method of drawing a predetermined pattern on a mold using a setting retarder, a step of casting mortar and removing the pattern from the form in the same manner as described above, The pattern is formed by passing through a step of washing out the uncured surface corresponding to the formed portion.

However, the paper pattern impregnated or coated with the cement setting retarder has low strength against the mortar composition. For this reason, the pattern paper is torn or the position is misaligned with the mold, and it is difficult to form a washout surface or a pattern on a predetermined portion of the concrete product.

Further, when a conventional setting retarder that directly suppresses the hydration mechanism of cement is used as a washout agent, the setting retarder quickly dissolves in the moisture in cement concrete. Therefore, with the bleeding phenomenon in which excess water is released from the cement concrete immediately after casting, the setting retarder contained in the pattern paper or applied to the inner surface of the form is dissolved, and the form is dissolved. To move along the surface,
There are many problems, such as the effect of the curing retarder in parts requiring washing out is greatly reduced, while the effect of curing retardation extends to parts not requiring washing out (hereinafter also referred to as lateral flow). Was not an appropriate method for the decorative method of concrete products.

As a method for solving these problems, the present inventors have utilized a water-insoluble polymer cement setting retarder,
Alternatively, it has been proposed that an existing low-molecular-weight water-soluble curing retarder is once mixed with a water-soluble resin having no cement curing retarding ability. In the method of using these resin compositions as a setting retarder, the resin composition itself having a cement setting retarding performance, or a resin composition containing an existing setting retarder, is processed into a film or sheet. (Hereinafter, also referred to as a cement composition retardation sheet or simply a cement retardation sheet) solves the problem of strength of a conventionally used pattern paper or the like.

For example, Japanese Patent Application Laid-Open No. 9-183643 discloses a technique in which a saturated or unsaturated polyester resin is coated on a base film to form a sheet, and this is used as a cement setting retardation sheet for surface treatment of concrete products. did. That is, the saturated or unsaturated polyester resin itself is water-insoluble and does not dissolve even when it comes into contact with the uncured cement composition, but is eventually hydrolyzed by alkali in the cement composition, and the cement An active ingredient that delays the cure results. The rate of this hydrolysis is accelerated by the heat generated by the hydration reaction of the cement, and peaks when bleed water is again consumed and lost in the hydration of the cement. Therefore, the setting delay component generated from the setting delay sheet no longer moves together with the bleed water, and the setting of only the target portion of the concrete product can be delayed. Further, since a polyethylene terephthalate film or the like is usually selected as the base film, the curing retardation sheet has a sufficient strength for casting concrete.

In Japanese Patent Application Laid-Open No. Hei 8-309717, a cement-setting retardation sheet is prepared by mixing aminotri (methylenesulfonic acid) and citric acid with a styrene-butadiene rubber latex, coating this on a polyethylene terephthalate film, and drying. And disclosed a technique for using it for the same purpose as above.

[0012] By these methods, it is possible to efficiently and extremely sharply wash out a target pattern at a target portion of a concrete product. However, in practical use, there is often a demand for adjusting the washing-out depth. For example, in the case of mortar mainly composed of sand and cement, and in the case of concrete in which gravel is added thereto, the latter generally requires a deeper washing effect. In addition, there are many demands for completing a more complicated washing pattern such as a striped pattern by alternately changing the washing depth applied to the concrete surface.

The general form of use of the cement setting retardation sheet is as follows. That is, first, the cement setting delay sheet is cut into a desired size, and then this is placed in a mold for molding a concrete product with the layer (cement setting delay layer) made of the cement setting delay resin composition facing up. It is laid by a method such as pasting using an adhesive or the like. Thereafter, a reinforcing material such as a reinforcing bar is provided as necessary, and a cement composition (concrete) adjusted at a predetermined mixing ratio is cast. After curing for a predetermined period of time, the concrete molded product is removed from the mold, and the portion of the concrete retardation sheet whose curing is inhibited is washed out with high-pressure water or the like to expose the aggregate in the concrete.

In the above process, the mode of action of the cement composition setting retarding resin composition is roughly as follows. That is,
When the setting retardant resin composition on the cement setting delay sheet encounters the cement composition in the mold, it absorbs the moisture in the cement composition and starts to swell gradually from the surface. When the cement setting retarding resin composition is water-soluble, the dissolution proceeds gradually from the swollen surface, and the contained setting retarding active ingredient is released to the uncured concrete surface. In the case of the type in which the cement setting retarding resin composition undergoes hydrolysis, hydrolysis proceeds gradually after similar swelling, and the generated active ingredient is released to the concrete surface. The setting delay component released on the concrete surface gradually diffuses from the concrete surface toward the inside, and sequentially captures calcium ions in the concrete to inhibit the setting of the cement. Since the release and diffusion of these active ingredients proceed through the process of absorbing, swelling, dissolving or hydrolyzing the water, the sheet progresses very slowly in the initial stage, and the hardening of concrete progresses. And increase its speed. In particular, the speed becomes maximum just before the concrete loses its fluidity under the influence of heat generated by the hardening of the concrete, and stops as soon as the free water in the concrete is lost.

Since the retardation of cure proceeds based on the mechanism described above, the retardation performance is determined by the hydrophilicity, dissolution rate, or hydrolysis rate of the cure retardation resin composition, and furthermore, the retardation effectiveness. It is closely linked to the diffusion rate of the component into the concrete, in other words, the depth of the setting delay that the setting delay component exerts on the concrete product surface layer (hereinafter, also referred to as the setting delay depth) is the value of the setting delay resin composition. It is governed by the composition itself and the properties of the substances constituting the composition, and therefore, in order to change the cure delay depth, it is usually necessary to make changes to the composition of the resin composition itself. Therefore, for example, in the case of a resin that has the ability to retard cement setting, by taking measures such as increasing the water solubility of the resin itself or the hydrolysis rate, it is also possible to add an existing setting retarder to the resin. The apparatus having the type of case,
By taking measures such as increasing the concentration of the curing retarder or increasing the water solubility of the resin serving as the matrix, the curing retardation depth can be increased. However, in this method, the dissolution rate of the curing retardation component increases at the same time, that is, the dissolution amount increases at the same time as the timing of dissolution of the curing retardation component increases. When added, the flow of the delay component due to the bleeding water of the concrete occurs as in the case where the existing cement setting retarder is directly applied to the wall surface of the formwork, and the delay effect extends to an unintended portion ( In many cases, the problem of cross flow occurs. Therefore, it is technically extremely difficult to change the composition of the curing retarder in various ways according to the required washing depth, and even if an appropriate composition is prepared, it is necessary to deal with them individually. Manufacturing sheets is not economically viable.

Among the cement setting retardation sheets prepared using the resin composition, those having a cement setting delaying resin coated on a base film having no cement setting delaying property have another problem in practical use. The point is pointed out. That is, for example, in the case of a sheet in which an unsaturated polyester resin is coated on a polyethylene terephthalate film, both the unsaturated polyester resin of the cement setting delay layer and the polyethylene terephthalate film of the base material are transparent. Therefore, the user of the sheet can hardly determine which side is the hardening delay layer. Needless to say, if the surface to be used is wrong, it is impossible to wash out the concrete surface. Cement setting delay layer,
Alternatively, an attempt to color only one of the base films has little effect on discriminating the front and back of this type of film.

[0017]

Accordingly, the first aspect of the present invention is as follows.
The purpose of the present invention is to use a resin composition having a cement setting delay property by itself, or a resin composition obtained by mixing an existing low molecular weight water-soluble cement setting delay material (hereinafter, these are combined together unless necessary, The depth of the cement setting delay sheet having a layer consisting of a layer consisting of a layer consisting of: (a setting delay depth) is increased without changing the composition of the cement setting delaying resin composition. Is to provide a way to do that.

It is another object of the present invention to provide a cement setting retardation sheet prepared by the method provided in the first object.

Still another object of the present invention is to provide a cement-retarded retardation sheet in which a layer comprising a cement-setting retardant resin composition is formed on a film as a base material, both of which are transparent. The goal is to provide a way to facilitate identification.

Another object of the present invention is to provide a cement composition hardening retardation sheet prepared by the method for facilitating the identification of the front and back sides.

[0021]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and have found that the setting retardation depth of the cement setting retardation sheet has a surface roughness of a certain level or more. It has been found that the transparent sheet can be enlarged by applying the unevenness having the above, and that it is extremely easy to identify the front and back sides of the transparent sheet by applying the unevenness, thereby completing the present invention.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION A layer composed of a resin composition having a cement setting retarding property by itself or a cement setting retarding resin composition such as a resin composition mixed with an existing cement setting retarder (hereinafter referred to as a cement setting delay layer) , Or simply coated on a base sheet made of a resin composition having no cement setting delay performance on a surface of a cement setting delay sheet having a cement setting delay layer. In (2), unevenness having a certain degree of roughness is applied to the surface of the cement setting retardation layer. More preferably, the setting retardation layer is the outermost layer of the cement setting retardation sheet, and the surface thereof is provided with irregularities having a certain degree of roughness, and the uneven surfaces of these sheets are brought into direct contact with the uncured cement composition, The contact surface inhibits or delays the hardening of the cement composition. The thickness of the uncured layer (delay layer) formed on the surface of the concrete composition molded article by such a method is such that the cement cured retardant sheet has no irregularities but has the same composition of the cement cured retardant resin composition and the layer. Is thicker (delay depth) than the uncured layer generated by

The resin having the ability to retard the setting of cement by itself is not particularly limited, but here, a resin of the type in which a functional group which inhibits or delays the setting of cement is already incorporated in the resin skeleton itself. And a type in which a component having a delay performance is produced by hydrolysis of a resin. For the type having a functional group that inhibits or delays the hardening of cement in the resin skeleton itself, a polymer having high hydrophilicity as a whole and having many functional groups capable of capturing calcium ion of cement in the molecule is preferable. Examples of the functional group capable of capturing calcium ions include a carboxyl group, a sulfate group, and a phosphate group. However, these groups do not necessarily need to be free acids, and may be any acid anhydrides or esters which can produce free acid groups by hydrolysis such as esters. As the acid group, a carboxyl group is preferable, and it is particularly preferable that the carboxyl groups have a positional relationship such that they can form a chelate with respect to calcium ions. Polymers satisfying these conditions include, for example, unsaturated polycarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and metaconic acid, and acid anhydrides and esters thereof, (meth) acrylic acid, Homopolymers such as ethylenically unsaturated monocarboxylic acids such as crotonic acid and esters thereof, copolymers, and saponified products thereof, and examples of the copolymer include vinyl ethers and allyl ethers, and Copolymers with other vinyl compounds and the like can be mentioned. Of these, particularly preferred polymers include a group of polymers represented by the general formula (2) or (3).

[0024]

Embedded image

Embedded image (Wherein R1 is an alkylene group having 2 to 4 carbon atoms, R2 is a hydrogen atom, an alkyl group, an acyl group, a cycloalkyl group,
An aryl group or an aralkyl group, R3 represents a hydrogen atom or a methyl group, and R4 represents a residue of a vinyl monomer. X represents a linear or branched alkylene group having 1 to 10 carbon atoms or a carbonyl group, m is 0 or 1, and n is 0 to 10
Indicates an integer of 0. f + g + h = 1, f is from 0 to 0.9, g is from 0 to 0.9, h is from 0 to 0.5) On the other hand, as a resin which produces a component having a cement setting retarding performance through hydrolysis. Is preferably a compound which produces a component having a carboxyl group by hydrolysis, and examples thereof include a saturated polyester resin, an unsaturated polyester resin and a cross-linked cured product thereof (including a self-cross-linked cured product).
Among them, a polyester comprising a glycol having 6 or less carbon atoms or a condensate thereof (oligomer and polymer, hereinafter referred to as polyglycol) and a polyvalent carboxylic acid having 6 or less carbon atoms and a copolymer thereof, and the like are particularly preferable. Can be exemplified. That is, carbon number 6
The following glycols or polyglycols thereof, more preferably glycols having 3 or less carbon atoms, or unsaturated polyesters comprising the polyglycols and maleic acid or fumaric acid (the structural unit is represented by the general formula (1)) Or a copolymer thereof is converted to a vinyl monomer having a hydroxyl group in the molecule, for example, 2-hydroxyethyl (meth)
An ester of acrylate or polyalkylene glycol (including its monoalkyl ether capable of forming a hydroxyl group by hydrolysis) and (meth) acrylic acid, or an ether of allyl alcohol, vinyl alcohol, or the like;
And the like, alone or as a mixture, and if necessary, a compound which is crosslinked and cured with another vinyl monomer.

[0025]

Embedded image (In the above formula, MA represents maleic acid and / or fumaric acid residue, and GL1 is a branched glycol residue having 6 or less carbon atoms or a condensate of a branched glycol having 6 or less carbon atoms (polymerization degree 20 or less) DA represents a polyvalent carboxylic acid residue other than maleic acid and fumaric acid and having 10 or less carbon atoms, and GL2 represents a polyvalent carboxylic acid residue other than GL1 and having 10 or less carbon atoms. And the residues of alcohols and their derivatives (including condensates), and q + r + s + t = 1,
q + s = r + t, and q + r ≧ 0.5. The resins exemplified above may be used alone or in combination. Further, as the third component, for example, a pigment, various stabilizers, a lubricant, a plasticizer, an inorganic filler, or the like may be added and used. Further, when the resin is a cross-linked cured product of an unsaturated polyester, it is usual that various peroxides are used as a cross-linking agent at the time of cross-linking, and further a curing accelerator such as cobalt naphthenate is added in advance.

A cement setting delay sheet can also be obtained by processing a composition obtained by mixing an existing cement setting retarder with a resin. In this case, the existing cement setting retarder is generally used by adding to and mixing with concrete in order to adjust the setting speed of cement. For example, zinc oxide, boron oxide, borax, zinc chloride, zinc oxide, fluorosilicon is used. Magnesium, inorganic hardening retarders such as, polyhydroxy compounds (sugar, alcohol, methylcellulose, ethylcellulose, polyvinyl alcohol, dextrin, etc.), sodium polyacrylate, oxycarboxylic acid or its salt, lignin sulfonate, gluconic acid or its Organic cement hardening retardants such as salts, keto acids such as pyruvic acid and alpha-ketoglutaric acid or salts thereof, and the like can be exemplified, and these are used alone or in combination with them.

The resin in which these cement setting retardants are mixed is not particularly limited, but is preferably as hydrophilic as possible, and particularly preferably a water-soluble resin or an alkali-soluble resin. For example, polyvinyl acetate and its copolymer, polyamide-based multi-component copolymer,
Examples thereof include polyester, poly (meth) acrylic acid and its copolymer, poly (meth) acrylic acid ester and its copolymer, and a polymer containing maleic acid or fumaric acid as a part of the monomer. , CMC
Water-soluble polymers such as (carboxymethylcellulose) and HEC (hydroxyethylcellulose) are preferred.

The method of processing the above-mentioned various cement setting retarding resin compositions into sheets is not particularly limited. Among the resins having the ability to retard the setting of cement by themselves, those having properties as a thermoplastic resin can be formed into a film by a usual extrusion molding method. Of course, it can be laminated on film, paper, woven fabric, non-woven fabric, and other various foils as a base material. On the other hand, for those having properties as a thermosetting resin such as a cured product of an unsaturated polyester, a film serving as a substrate, for example, a polyethylene terephthalate film, or after being coated on a polypropylene film in an uncured state, The sheet can be formed by performing a curing treatment using heat or another method. Of course, after the curing treatment, the coated resin layer may be peeled off from the base film to form a single-layer film having no base film.

It is also possible to consider a case where a composition obtained by mixing an existing cement setting retarder with a resin is formed into a sheet. That is, an extrusion molding method, a method of coating a base film, or the like is selected according to the properties of the resin serving as the matrix. In addition, when the cement setting retardant resin composition is soluble in an organic solvent, or when supplied as an emulsion, it can be coated on a base film and then dried to form a sheet. Accordingly, after drying, the cement setting retarding layer can be peeled off from the substrate sheet to finish as a single layer sheet.

[0030] The thickness of the cement setting retardation sheet produced by such a method is not particularly limited. In general, a sheet composed of a single layer of the cement setting retarding resin composition has a thickness of 10 μm or more and 2 mm or less, and more generally 50 μm or more and 1 mm or less, although it depends on the condition of the unevenness of the sheet surface described later. It is easy to handle objects of about 100 microns to 300 microns in millimeters or less. Even in the case of a composite sheet in which a layer made of a cement setting retarding resin composition is provided on a base sheet, the total thickness thereof is considered to be the same as that of the single-layer sheet, and the cement setting delaying resin composition The thickness of the layer of material often ranges from 5 microns to 1 millimeter, more usually from tens to hundreds of microns. When impregnating the paper or nonwoven fabric with the cement setting retardant resin composition, the thickness of the sheet is often governed by the thickness of the paper or nonwoven fabric used, and is often several tens to several hundreds of microns.

The cement setting retarding sheets thus obtained have their own cement setting delaying ability, but extend the delay depth without changing the composition of the cement setting delaying resin composition. The method is described below.

The present inventor has found that when the surface of the curing retardation layer of the curing retardation sheet is provided with irregularities of a certain degree or more, the curing retardation depth increases. Moreover, it does not involve any enlargement of the cross-flow phenomenon often observed in adjusting the cure delay depth by changing the composition. It is not clear how the unevenness exerts the effect of increasing the curing delay depth. Probably, the unevenness increases the surface area, and consequently increases the supply of the cement setting delay component per unit area of the concrete surface, thereby increasing the delay depth. However, since there is no change in the timing of the release of the delayed component, it is considered that the cross flow phenomenon does not occur.

In order to enlarge the cure retardation depth to such an extent that a significant difference is recognized, there is no particular limitation on the shape of the irregularities provided on the surface of the cure retardation layer, but the roughness is not less than a certain limit. Need a degree.

That is, the unevenness of the surface of the hardening delay layer is perpendicular to each other by a surface roughness measuring device manufactured by Tokyo Seimitsu Co., Ltd., Surfcom 470 / 570A series, or an apparatus corresponding thereto. In the direction, the measurement length (S) is measured by 10 millimeters at a time, and when the cross section curve of the unevenness is obtained, the length of the ridge line of each cross section curve (P)
The average of the ratio (P / S) to the measured length must be 1.15 or more, more preferably 1.25 or more, and still more preferably 1.3 or more.

If the ratio of the length of the ridge line of the cross-sectional curve to the measured length is 1.15 or less, the depth of cure delay is not sufficiently increased.

The method of obtaining the ratio of the length of the cross-sectional curve to the measured length will be described in more detail. As shown in FIG. The surface is scanned at an arbitrary position in the X and Y-axis directions by 10 mm. The cross-sectional curves of the unevenness obtained as a result of the measurement are, for example, FIGS. The ratio (P1 / S and P1 / S) of the measured length (distance (S) between ab and cd, ie, 10 mm) and the length (P1, P2) of the ridge between ab and cd is determined. ,
Calculate the average.

The method for forming the irregularities on the surface of the curing retardation sheet is not particularly limited, and any method may be employed. For example, the following method can be exemplified as a specific method.

In preparing the cement setting retardation sheet, a particulate additive is mixed with the cement setting delaying resin composition,
By forming this into a sheet, the necessary irregularities can be given to the cement setting retardation layer. The type of the granular material giving the unevenness is not particularly limited, and any type may be used as long as it does not inhibit the cement setting delay function of the cement setting delaying resin composition. Also, there is no particular limitation on the shape and size of the granular material, but in general, a spherical material is cheaper to handle than a columnar or rod-like material, and a particle having a particle diameter of about 50 to several hundred microns is generally used. easy to handle. Specific examples of such granules include sand, glass powder, glass beads,
In addition to glass balloons, powders of calcium carbonate, kaolin, zinc oxide, silica, plastics, rubber, etc.,
Fibrous granular materials such as glass fiber, synthetic fiber, and paper can be exemplified.

The amount of these particulates to be added to the base material varies depending on the specific gravity, dispersibility, required surface roughness, thickness of the hardening delay layer, etc. of each granular material. In the case of 10 microns, when the particulate matter is sand, glass powder, or silica powder, it is 0.5% to 30%, more preferably 1% to 10%, and still more preferably 2% to 5%. If the added amount of the particulate matter is 30% or more, it becomes difficult to form the film and to handle the sheet, and the retarding effect of the cement setting retarding component may be affected. or,
If the addition amount is 0.5% or less, sufficient unevenness cannot be obtained in the cement setting delay layer, and it becomes difficult to obtain the desired effect of increasing the delay depth.

The method of mixing these granules with the resin composition for delayed setting of cement may be a generally known method. If the resin composition is a solid, it is converted into granules or powder, and other raw materials are used. After thoroughly mixing the granular material with the substance, the mixture may be kneaded with an extruder or the like and formed into a sheet. When the resin composition is in a liquid state before being processed into a sheet, the granular material may be mixed therewith using a mixer or the like, and then coated on a film as a base material to form a sheet. However, in forming these sheets, for example, when forming a sheet by extrusion molding, the surface to be provided with irregularities immediately after extrusion or immediately after coating when coating on a base film, for example, by a roll or the like before it is cured It goes without saying that there must be no step of smoothing the unevenness.

Another method of providing the unevenness is a method of transferring the pattern from a matrix. For example, a setting retarder composed of a resin that can be applied by extrusion molding, or an existing lignin-based or oxycarboxylic acid-based curing retarding agent mixed with an extrudable resin, and formed into a sheet by extrusion molding In this case, the surface of the curing retardation layer of the sheet extruded from the T-die can be provided with irregularities by pressing an engraving roll serving as a matrix of the desired irregularities. A pattern in which the unevenness is in the above-described range is engraved on the matrix of the unevenness, and the unevenness may be a grain pattern, a satin pattern, or a rack pattern.

As another method of providing unevenness, for example, when the cement setting retarding resin composition is a dope containing an organic solvent before the sheet processing, or diluted with a crosslinking agent. In the case of unsaturated polyester, sheet processing employs a technique called coating on the base film, but at this time, the granular material is temporarily attached to the base film surface in advance using an adhesive or an adhesive. After that, a method of applying the liquid resin composition and drying or crosslinking and curing the resin composition to obtain irregularities is also effective. Further, when these liquid resin compositions are coated, they often form fine wrinkles in a drying or heat treatment step. This phenomenon of wrinkles can be effectively used for forming irregularities.

In the cement setting retardation sheet having the irregularities described herein, it is preferable that the outermost layer provided with the irregularities is occupied by a layer made of the cement setting retarding resin composition. However, this is not an essential requirement of the present invention. It is not limited that there is a top coat layer made of a water-soluble polymer provided for the purpose of protecting the hardening delay layer on the hardening delay layer, if necessary.

The thus obtained cement setting retardation sheet having irregularities on the surface is laid on the inner surface of the concrete molding form, with the cement setting delay layer facing up, via an adhesive or a pressure-sensitive adhesive as required. Then, if necessary, a reinforcing bar is arranged on the upper surface, and then concrete is poured. After demolding the concrete molded product cured after a predetermined curing period and removing the cement setting delay sheet, the contact surface of the concrete molded product with the sheet is washed using high-pressure water or the like to remove the aggregate. Wash out. The washout depth of the washout surface thus obtained is deeper than the washout depth obtained by using a cement setting retardation sheet having no irregularities but having the same composition of the cement setting delaying resin composition and the layer.

Another object of the present invention is to identify the front and back of a cement-setting retardation sheet in which both layers are transparent among the cement-setting retardation sheets in which a layer comprising a cement setting retardation resin composition is formed on a film as a substrate. Is to provide a way to facilitate The unevenness provided for increasing the curing delay depth can be very easily recognized by palpation. That is, it is possible to easily identify the front and back sides of the cured retardation sheet composed of the base film and the curing retardation layer by palpation, which surface is the curing retardation layer. This is extremely effective in preventing the use of the front and back of the cement setting delay sheet by mistake, and as a result, it is impossible to wash out the concrete molded product, resulting in a large economic loss.

When only the front and back sides of the cement setting retardation sheet are to be distinguished, it is not necessary to satisfy the above-mentioned conditions with respect to the location of the unevenness and the surface roughness thereof, as long as the front and back sides can be distinguished by touch. . Therefore, when forming the irregularities by adding the granular material, it is often sufficient even if the addition amount of the granular material is 2% or less.

[0047]

EXAMPLES The effect of the depth of setting delay indicated by the concavo-convex pattern given to the surface of the cement setting delay sheet will be described below.
While comparing with the delay depth having a smooth ordinary curing delay sheet having no uneven pattern, it will be described with examples,
The present invention is not limited by these examples.

[0048]

Example 1 100 parts by weight of an unsaturated polyester resin having a number average molecular weight of 2500 composed of maleic anhydride and propylene glycol was mixed with 10 parts by weight of a styrene monomer and
-Dissolved in 60 parts by weight of hydroxyethyl methacrylate and used as a polymerization initiator perbutyl o (Nippon Oil & Fats Co., Ltd.)
2 parts by weight) and 1 part by weight of Aerosil 200 (Nippon Aerosil Co., Ltd.) as a granular material for forming an uneven pattern. The dope thus obtained was applied to a polyethylene terephthalate film having a thickness of 40 μm using a bar coater at a thickness of 60 μm, and crosslinked and cured in an oven at 150 ° C. for 10 minutes to obtain a cement setting retardation sheet A1. .

[0049]

Example 2 A cement setting retardation sheet A2 was obtained in the same manner as in Example 1 except that the additive of Aerosil 200 was changed to 2 parts.

[0050]

Example 3 A cement setting retardation sheet A3 was obtained in the same manner as in Example 1 except that the additive amount of Aerosil 200 was changed to 5 parts.

[0051]

Example 4 A paper and cement setting retardation sheet A4 were obtained in the same manner as in Example 1 except that the additive amount of Aerosil 200 was changed to 10 parts.

[0052]

Example 5 A cement setting retardation sheet B was obtained in the same manner as in Example 1, except that the granular material to be added was 20 parts by weight of glass beads having an average particle diameter of 500 microns.

[0053]

Example 6 Maleic anhydride 60 g, vinyl acetate 1
40 grams, azobisisobutyronitrile (AIBN)
2 grams were mixed and 1/3 volume of the mixture, ie 67.
3 grams into a 1 liter separable flask
Polymerization was started at 65 ° C. under stirring with 0 g of ethyl acetate, and after 15 minutes, 134.7 g of the remaining amount of the above mixture was charged over 2 hours. When the charging was completed, the temperature was raised to 75 ° C. The polymerization was terminated by raising the temperature and further stirring for 1 hour. The dope obtained after the completion of the polymerization was air-dried on a stainless steel tray for one day, further dried for one day in a vacuum dryer, and pulverized to obtain granules of vinyl maleic anhydride copolymer resin. The granules have a rack pattern having a cross section of an equilateral triangle with one side of 1 mm,
Also, the surface is sprayed on a mold made of a brass plate treated with a release agent so that the total layer height is about 4 mm, a 2 mm thick brass plate is stacked, and pressed at 170 ° C. It was molded to obtain a cement setting retardation sheet C having a rack pattern having a cross section of an equilateral triangle having one side of 1 mm on the surface.

[0054]

Example 7 5 parts by weight of sodium acrylate and 0.5 part by weight of gluconic acid were dissolved in 100 parts by weight of water to prepare an aqueous solution of a cement setting retarder. Next, glass beads having an average particle diameter of 1 mm were sprayed on a 5 cm-wide packing adhesive tape, and the beads were uniformly attached. This tape is immersed in the previously prepared aqueous solution of cement setting retarder,
After withdrawing, roughly terminate the dripping of the viscous solution,
This was air-dried, and then dried for one day with a vacuum dryer to obtain a cement setting retardation sheet D.

[0055]

Comparative Example 1 A cement setting retardation sheet E1 was prepared in the same manner as in Example 1 except that Aerosil 200 was not added.

[0056]

Comparative Example 2 A cement setting retardation sheet E2 was obtained in the same manner as in Example 1 except that the amount of Aerosil 200 was changed to 0.1 part.

[0057]

Comparative Example 3 Unsaturated polyester dope coating thickness of 2
A cement setting retardation sheet F was obtained in the same manner as in Comparative Example 1 except that the thickness was set to 00 microns.

[0058]

Comparative Example 4 A cement setting retardation sheet G was obtained in the same manner as in Example 5 except that the amount of glass beads added was changed to 2 parts by weight.

[0059]

Comparative Example 5 The smooth back surface of the cement setting retardation sheet C obtained in Example 6 was used as the cement setting delay sheet C back.

[0060]

Comparative Example 6 Cement retardation sheet D obtained in Example 7
Was set as the cement setting retardation sheet D back.

The unevenness of the uneven pattern on the surface of the hardened rolled layer of each of the cement setting retardation sheets obtained in Example 1 to Comparative Example 6 was measured using a surface roughness shape measuring instrument, SURFCOM 575, manufactured by Tokyo Seimitsu Co., Ltd. , Measuring length 1 in two directions perpendicular to each other
The measurement was performed at 0 mm, and two cross-sectional curves of the uneven pattern were obtained. Table 1 shows the average of the ratio of the length of the ridge line to the measured length of the obtained cross-sectional curve.

Table 1 also shows the setting delay depth measured as follows for each of the obtained cement setting delay sheets.

[0063]

[Table 1] (Measurement method of cement setting delay depth) A sample cement setting delay sheet was cut into 6 cm x 7 cm, and this was cut into 15 c
After sticking to the bottom surface of a polyvinyl chloride vat of mx 20 cm using a double-sided adhesive tape with the setting retardation layer side facing upward, 28.2 parts by weight of cement, standard sand (JIS, R5201) 56.3 parts by weight, water 15.5
Mortar consisting of parts by weight was charged so as to have a layer height of 3 cm, and allowed to stand at 20 ° C. for 24 hours. Thereafter, the hardened mortar was removed from the mold, the cement setting delay sheet adhering to the bottom surface was peeled off, and the entire bottom surface including the peeled surface was washed with water using a brush to perform a washing operation. The washing depth (hardening delay depth) of the washing surface thus obtained was measured using a laser displacement meter. Table 1 shows the results of the measurement together with the possibility of discrimination between the front and back sides with OX.

[0064]

The effect of the present invention is to provide an uneven pattern on the cement composition curing retardation sheet, so that the surface of the cement composition molded article is
It is possible to provide a concrete washing foundation in which a deep washing pattern without disturbance or a deeply exposed aggregate is provided.

[Brief description of the drawings]

FIG. 1 is a top view of an a-b curve and a cd curve for measuring the undulation state of an uneven pattern of a cement setting retardation sheet.

FIG. 2 is a cross-sectional curve measured between a and b.

FIG. 3 is a cross-sectional curve measured between cd.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI E04G 9/10 101 E04G 9/10 101A

Claims (13)

[Claims] 1. A cement composition hardening retardation sheet having a layer composed of a resin composition having a cement setting retarding performance by itself or a resin composition mixed with a cement setting retarder, by forming irregularities on the surface of the layer. And a method of further increasing the depth of delaying the hardening of the cement composition. 2. A cement composition hardening retardation sheet having a layer composed of a resin composition having a cement setting retarding property by itself or a resin composition mixed with a cement setting retarder, wherein the surface of the layer has irregularities. Cement setting delay sheet. 3. The hardening of a cement composition according to claim 2, wherein a layer of a resin composition having a cement hardening retarding property by itself or a resin composition mixed with a cement hardening retardant constitutes a surface having irregularities. Delay sheet. 4. The method according to claim 1, wherein the unevenness is formed so that the average of the ratio of the length of the ridgeline to the measured length of the unevenness is 1.15 or more. The cement composition curing retardation sheet according to the above. 5. The method according to claim 1, wherein the undulations are formed so that the average of the ratio of the length of the ridge line to the measured length of the undulations is 1.25 or more. The cement composition curing retardation sheet according to any one of the above. 6. The method according to claim 1, 4 or 5, wherein the irregularities are formed by mixing a granular material with any of the compositions constituting the cement composition setting retardation sheet. 6. The cement composition curing retardation sheet according to any one of 2 to 5. 7. The method according to claim 1, wherein the irregularities are formed by mixing a particulate material with the composition constituting the surface layer of the cement composition hardening retardation sheet, or The cement composition curing retardation sheet according to claim 2. 8. Irregularities are such that a resin having a cement composition hardening retarding property or a resin composition having a cement setting retarder mixed thereon is obtained by spraying and temporarily adhering a granular material on a base material sheet. The method according to any one of claims 1 to 4, or the sheet according to any one of claims 2 to 7, which is applied by forming a layer comprising: 9. The method according to claim 1, wherein the unevenness is formed by transferring the unevenness from a matrix.
Or the cement composition hardening delay sheet according to any one of claims 2 to 8. 10. The method according to claim 1, wherein the resin having the ability to retard cement setting is a saturated polyester resin, an unsaturated polyester resin, or a crosslinked cured product of an unsaturated polyester. Or the cement composition hardening delay sheet according to any one of claims 2 to 9. 11. A resin having a cement setting retarding property by the general formula (1): ## STR1 ## (In the above formula, MA represents maleic acid and / or fumaric acid residue, and GL1 is a branched glycol residue having 6 or less carbon atoms or a condensate of a branched glycol having 6 or less carbon atoms (polymerization degree 20 or less) DA represents a polyvalent carboxylic acid residue other than maleic acid and fumaric acid and having 10 or less carbon atoms, and GL2 represents a polyvalent carboxylic acid residue other than GL1 and having 10 or less carbon atoms. And the residues of alcohols and their derivatives (including condensates), and q + r + s + t = 1,
q + s = r + t, and q + r ≧ 0.5. 11) The method according to any one of claims 1 or 4 to 10, or the curing of the cement composition according to any one of claims 2 to 10, which is an unsaturated polyester comprising a structural unit represented by Delay sheet. 12. A resin having a cement-setting retarding property by itself represented by the general formula (2) or (3): Embedded image (Wherein R1 is an alkylene group having 2 to 4 carbon atoms, R2 is a hydrogen atom, an alkyl group, an acyl group, a cycloalkyl group,
An aryl group or an aralkyl group, R3 represents a hydrogen atom or a methyl group, and R4 represents a residue of a vinyl monomer. X represents a linear or branched alkylene group having 1 to 10 carbon atoms or a carbonyl group, m is 0 or 1, and n is 0 to 10
Indicates an integer of 0. f + g + h = 1, where f represents 0 to 0.9, g represents 0 to 0.9, and h represents 0 to 0.5)
12. The method according to claim 1, which is a resin comprising a structural unit represented by the formula:
12. The cement composition curing retardation sheet according to any one of items 1 to 11. 13. Use of the cement composition curing retardation sheet according to any one of claims 2 to 12 to delay or inhibit the curing of the cement composition on the surface of a molded article, structure, or building made of the cement composition. And then removing the uncured cement composition to obtain a washed surface.