JP2016190751A - Cement clinker and cement composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cement clinker and a cement composition, having a color tone controlled within a predetermined range.SOLUTION: A cement clinker includes 5 mass% or more and 15 mass% or less of CA, 5 mass% or more and 15 mass% or less of CAF, 0.79 mass% or more and 2.30 mass% or less of MgO, 0.30 mass% or more and 0.94 mass% or less of TiO, and 0.10 mass% or more and 0.30 mass% or less of MnO. A cement composition includes 4.5 mass% or more and 15 mass% or less of CA, 4.5 mass% or more and 15 mass% or less of CAF, 0.71 mass% or more and 2.30 mass% or less of MgO, 0.27 mass% or more and 0.94 mass% or less of TiO, and 0.09 mass% or more and 0.30 mass% or less of MnO.SELECTED DRAWING: None

Description

  The present invention relates to a cement clinker and a cement composition, and more particularly, to a cement composition and a cement clinker having an adjusted color tone.

  It is important to adjust the color tone of cement when manufacturing cement used for concrete for buildings. For example, when remodeling a concrete building that has already been constructed, when new concrete is cast, if the color of the cement used for the new concrete is different from the past, the old concrete part and the new concrete part There is a problem in that a difference in color tone occurs between the two, and the overall beauty is impaired. Therefore, a cement adjusted to a desired color tone is required.

Conventionally, as a method of obtaining a cement with an adjusted color tone, a method of adjusting the amount of aluminum or iron contained in the cement is known. For example, Patent Document 1 below discloses a method for adjusting the color tone of a cement clinker by adjusting the content of C ₄ AF in the cement clinker.

JP 2008-239397 A

However, the color tone of the cement clinker and the cement composition is influenced not only by the content of C ₄ AF but also by various other components contained in the cement clinker and the cement composition. Therefore, as described in Cited Document 1, only by adjusting the content of C ₄ AF contained in the cement clinker or cement composition, a cement clinker or cement composition having a desired color tone can be obtained. It was insufficient.

  In view of the above problems, an object of the present invention is to provide a cement clinker and a cement composition whose color tone is adjusted within a predetermined range.

The cement clinker of the present invention comprises 5% by mass or more and 15% by mass or less C ₃ A, 5% by mass or more and 15% by mass or less C ₄ AF, 0.79% by mass or more and 2.30% by mass or less MgO; 0.30 mass% or more and 30 mass% or 0.94 mass% of TiO ₂ and 0.10 wt% or more comprises the following MnO.
Here, the contents of C ₃ A and C ₄ AF in the cement clinker indicate values calculated based on the Borg calculation formula from the contents of Al ₂ O ₃ and Fe ₂ O _{3 in} the cement clinker.

  In such a cement clinker, since each of the above components is included in the predetermined range, the b value in the Lab color space of the cement clinker is adjusted within a range of 6 to 9. That is, according to the present invention, a cement clinker having an adjusted color tone can be provided.

  Further, the cement clinker according to the present invention is preferably a Zn component of 0.10 to 0.80% by mass, an Sr component of 0.20 to 1.0% by mass, 0.10% by mass. It further contains one or more of a Ba component of 0.50 mass% or less or a Cu component of 0.05 mass% or more and 0.25 mass% or less.

  Since such a cement clinker further contains the trace element in the predetermined range, it is possible to provide a cement composition in which the b value in the Lab color space of the cement clinker is adjusted in more detail.

The cement composition of the present invention comprises 4.5 mass% to 15 mass% C ₃ A, 4.5 mass% to 15 mass% C ₄ AF, 0.71 mass% to 2.30 mass%. MgO, 0.27% by mass or more and 0.94% by mass or less TiO ₂ and 0.09% by mass or more and 0.30% by mass or less MnO.
Here, the contents of C ₃ A and C ₄ AF in the cement composition indicate values calculated based on the Borg calculation formula from the contents of Al ₂ O ₃ and Fe ₂ O _{3 in} the cement clinker. .

  In such a cement composition, since each said component is included in the said predetermined range, b value in the Lab color space of this cement composition is adjusted in the range of 6-9. That is, according to the present invention, it is possible to provide a cement composition whose color tone is adjusted.

  The cement composition according to the present invention is preferably 0.09% by mass or more and 0.80% by mass or less of Zn component, 0.18% by mass or more and 1.0% by mass or less of Sr component, 0.09% by mass. % Or more and 0.50% by mass or less of Ba component or 0.045% by mass or more and 0.25% by mass or less of Cu component are further included.

  In such a cement composition, since the trace element is further contained in the predetermined range, a cement composition in which the b value in the Lab color space of the cement composition is adjusted in more detail can be provided.

  According to the present invention, it is possible to provide a cement clinker and a cement composition whose color tone is adjusted within a predetermined range.

Details of the present invention will be described below. In the present specification, the _{C 3} A, shows a component represented by the formula 3CaO · _Al 2 _{O 3,} and _C 4 AF, represented by Chemical Formula _{4CaO · Al 2 O 3 · Fe} 2 O 3 Ingredients are shown. The C ₃ S, indicates the component represented by the chemical formula 3CaO · SiO _2, and _{C 2} S, indicating the component represented by the chemical formula 2CaO · SiO _2.
In the present specification, the contents of C ₃ A, C ₄ AF, C ₃ S, and C ₂ S in the cement clinker or cement composition are the same as those in the cement clinker or cement composition unless otherwise specified. The value calculated from the content of Al ₂ O ₃ , Fe ₂ O ₃ , CaO, and SiO _{2 in} the graph is based on the Borg calculation formula.

(Cement clinker)
The cement clinker of the present invention comprises 5% by mass or more and 15% by mass or less C ₃ A, 5% by mass or more and 15% by mass or less C ₄ AF, 0.79% by mass or more and 2.30% by mass or less MgO; 0.30 mass% or more and 30 mass% or 0.94 mass% of TiO ₂ and 0.10 wt% or more comprises the following MnO.
Since the cement clinker of the present invention includes the above components in the predetermined range, the b value in the Lab color space of the cement clinker is adjusted within a range of 6 to 9. That is, according to the present invention, a cement clinker having an adjusted color tone can be provided.

More specifically, the amount of C ₃ A contained in the cement clinker of the present invention may be 5% by mass or more and 15% by mass or less, and preferably 5.5% by mass or more with respect to the total mass of the cement clinker. It may be 14% by mass or less, more preferably 6.0% by mass or more and 13.5% by mass or less.
The amount of C ₄ AF contained in the cement clinker of the present invention may be 5% by mass or more and 15% by mass or less, and preferably 5.0% by mass or more and 14% by mass or less with respect to the total mass of the cement clinker. More preferably, it may be 5.5% by mass or more and 13% by mass or less.

Incidentally, the cement clinker is typically in addition to the _{C 3} A and _C 4 AF, _{C 3} S and _{C 2} S are also included, but the _{C 3} S and _{C 2} S contained in the cement clinker of the present invention The amount is not particularly limited.
Preferably, the amount of C ₃ S contained in the cement clinker of the present invention may be 50% by mass or more and 70% by mass or less, and more preferably 52% by mass or more and 68% by mass with respect to the total mass of the cement clinker. % Or less.
Preferably, the amount of C ₂ S contained in the cement clinker of the present invention may be 10% by mass or more and 30% by mass or less, and more preferably 12% by mass or more and 28% by mass with respect to the total mass of the cement clinker. % Or less.

  The amount of MgO contained in the cement clinker of the present invention may be 0.79% by mass or more and 2.30% by mass or less, preferably 0.85% by mass or more and 2% by mass with respect to the total mass of the cement clinker. It may be .25% by mass or less, more preferably 0.90% by mass or more and 2.20% by mass or less.

The amount of TiO ₂ contained in the cement clinker of the present invention may be 0.30% by mass or more and 0.94% by mass or less, preferably 0.35% by mass or more and 0.0. It may be 90% by mass or less, more preferably 0.40% by mass or more and 0.87% by mass or less.

  The amount of MnO contained in the cement clinker of the present invention may be 0.10% by mass or more and 0.30% by mass or less, preferably 0.12% by mass or more and 0.28% by mass with respect to the total mass of the cement clinker. It may be 0.1% by mass or less, more preferably 0.15% by mass or more and 0.25% by mass or less.

In the cement clinker of the present invention, the greater the amount of TiO ₂ contained in the cement clinker, the greater the b value in the Lab color space of the cement clinker, and the greater the amount of MnO contained in the cement clinker, The b value in the clinker Lab color space is reduced. Therefore, in the cement clinker of the present invention, the b value of the cement clinker is adjusted in more detail within the range of 6 to 9 by adjusting the amount of TiO ₂ and MnO contained in the cement clinker within the above range. can do.

For example, when it is desired to obtain the cement clinker of the present invention having a b value of 6 or more and less than 7, the TiO ₂ content of the cement clinker is adjusted to 0.34 mass% or more and 0.69 mass% or less, The MnO content may be adjusted to 0.11% by mass or more and 0.30% by mass or less. Preferably, the TiO ₂ content is set to 0.34% by mass or more and 0.54% by mass or less, and MnO What is necessary is just to make content into 0.25 mass% or more and 0.30 mass% or less.
Further, when it is desired to obtain the cement clinker of the present invention having a b value of 7 or more and less than 8, the TiO ₂ content of the cement clinker is adjusted to 0.34% by mass or more and 0.94% by mass or less, The content of MnO may be adjusted from 0.11% by mass to 0.30% by mass, preferably, the content of TiO ₂ is set to 0.54% by mass to 0.73% by mass, and MnO The content may be 0.17% by mass or more and 0.25% by mass or less.
When the cement clinker of the present invention having a b value of 8 or more and 9 or less is desired, the TiO ₂ content of the cement clinker is adjusted to 0.34 mass% or more and 0.94 mass% or less, The content of MnO may be adjusted to 0.11% by mass or more and 0.25% by mass or less. Preferably, the content of TiO ₂ is set to 0.73% by mass or more and 0.94% by mass or less. What is necessary is just to make content into 0.11 mass% or more and 0.17 mass% or less.

Moreover, the cement clinker of the present invention may contain SO ₃ . Preferably, the amount of SO ₃ contained in the cement clinker of the present invention may be 0.5% by mass or more and 3.0% by mass or less, more preferably 0.69% with respect to the total mass of the cement clinker. It may be not less than 2% by mass and not more than 2.77% by mass.

Furthermore, the cement clinker of the present invention may contain a trace element such as a metal element. Examples of such trace elements include Zn, Sr, Ba, Cu, Li, Pb, Mo, Cd, and Ni.
For example, the cement clinker of the present invention may contain 0.10 mass% or more and 0.80 mass% or less of a Zn component. In the cement clinker of the present invention, as the amount of Zn contained in the cement clinker increases, the b value in the Lab color space of the cement clinker decreases.
Moreover, the cement clinker of the present invention may contain 0.20% by mass or more and 1.0% by mass or less of an Sr component. The cement clinker of the present invention may contain 0.10 mass% or more and 0.50 mass% or less of Ba component. The cement clinker of this invention may contain 0.05 mass% or more and 0.25 mass% or less of Cu component. The cement clinker of the present invention may contain 0.10 mass% or more and 0.30 mass% or less of Li component.

_{Incidentally, C 3 A, C 4 AF} , C 3 S, C 2 Al for calculating the amount of _{S 2 O 3, Fe 2 O} 3, CaO, SiO ₂ content contained in the cement clinker of the present invention The contents of MgO, TiO ₂ , MnO, and SO ₃ in the cement clinker of the present invention are values measured by JIS R 5204 “Method for X-ray fluorescence analysis of cement”.
Further, the content of the trace element in the cement clinker of the present invention is described in JIS R 5202 Annex 6. Value obtained by measuring the cement clinker of the present invention prepared according to the method described in “Preparation of cement sample” by mixed acid decomposition-ICP emission spectrometry using a mixed acid of nitric acid, hydrofluoric acid and perchloric acid. Say. More specifically, it refers to a value obtained by measurement by the method described in the examples described later.

(Cement composition)
The cement composition of the present invention comprises 4.5 mass% to 15 mass% C ₃ A, 4.5 mass% to 15 mass% C ₄ AF, 0.71 mass% to 2.30 mass%. MgO, 0.27% by mass or more and 0.94% by mass or less TiO ₂ and 0.09% by mass or more and 0.30% by mass or less MnO.
The cement composition of the present invention also includes the above-described components in the predetermined range, so that the b value in the Lab color space of the cement composition is adjusted in the range of 6 to 9. That is, according to the present invention, it is also possible to provide a cement composition whose color tone is adjusted.

More specifically, the amount of C ₃ A contained in the cement composition of the present invention may be 4.5 mass% or more and 15 mass% or less with respect to the mass of the entire cement composition, preferably 4. 9 mass% or more and 14 mass% or less, More preferably, 5.4 mass% or more and 13.5 mass% or less may be sufficient.
Further, the amount of C ₄ AF contained in the cement composition of the present invention may be 4.5% by mass or more and 15% by mass or less, preferably 4.5% by mass or more, with respect to the mass of the entire cement composition. It may be 14% by mass or less, more preferably 4.9% by mass or more and 13% by mass or less.

The amount of C _{3 S} and C _{2 S} contained in the cement composition of the present invention is not particularly limited.
Preferably, the amount of C ₃ S contained in the cement composition of the present invention may be 45% by mass or more and 70% by mass or less, and more preferably 46% by mass or more and 68% by mass with respect to the total mass of the cement clinker. The mass% or less may be sufficient.
Preferably, the amount of C ₂ S contained in the cement clinker of the present invention may be 9% by mass or more and 30% by mass or less, more preferably 10% by mass or more and 28% by mass with respect to the total mass of the cement clinker. % Or less.

  Further, the amount of MgO contained in the cement composition of the present invention may be 0.71% by mass or more and 2.30% by mass or less, preferably 0.76% by mass with respect to the total mass of the cement composition. The amount may be 2.25% by mass or less, more preferably 0.81% by mass or more and 2.20% by mass or less.

The amount of TiO ₂ contained in the cement composition of the present invention may be 0.27% by mass or more and 0.94% by mass or less, preferably 0.31% by mass or more, based on the total mass of the cement composition. It may be 0.90 mass% or less, more preferably 0.36 mass% or more and 0.87 mass% or less.

  The amount of MnO contained in the cement composition of the present invention may be 0.09% by mass or more and 0.30% by mass or less, preferably 0.10% by mass or more and 0% by mass with respect to the total mass of the cement composition. 28 mass% or less, more preferably 0.13 mass% or more and 0.25 mass% or less.

In the cement composition of the present invention, as the amount of TiO ₂ contained in the cement composition increases, the b value in the Lab color space of the cement composition increases, and the amount of MnO contained in the cement composition increases. The b value in the Lab color space of the cement composition becomes smaller. Therefore, in the cement composition of the present invention, by adjusting the amount of TiO ₂ and MnO contained in the cement composition within the above range, the b value of the cement composition is more within the range of 6-9. Can be adjusted in detail.

Moreover, the cement composition of the present invention may contain SO ₃ . Preferably, the amount of SO ₃ contained in the cement composition of the present invention may be 0.5% by mass or more and 3.0% by mass or less, more preferably 0% by mass with respect to the total mass of the cement composition. It may be from .62% by mass to 2.77% by mass.

Furthermore, the cement composition of the present invention may contain a trace element such as a metal element. Examples of such trace elements include Zn, Sr, Ba, Cu, Li, Pb, Mo, Cd, and Ni.
For example, the cement composition of the present invention may contain 0.09% by mass or more and 0.80% by mass or less of the Zn component. In the cement composition of the present invention, the b value in the Lab color space of the cement composition decreases as the amount of Zn contained in the cement composition increases.
Moreover, the cement composition of the present invention may contain 0.18% by mass or more and 1.0% by mass or less of an Sr component. The cement composition of the present invention may contain 0.09% by mass or more and 0.50% by mass or less of Ba component. The cement composition of the present invention may contain 0.045 mass% or more and 0.25 mass% or less of a Cu component. The cement composition of the present invention may contain 0.09% by mass or more and 0.30% by mass or less of Li component.

In addition, the content of Al ₂ O ₃ , Fe ₂ O ₃ , CaO, and SiO ₂ for calculating the amount of C ₃ A, C ₄ AF, C ₃ S, and C ₂ S contained in the cement composition of the present invention The amount and the content of MgO, TiO ₂ , MnO, and SO ₃ in the cement composition of the present invention are values measured by JIS R 5204 “Method for X-ray fluorescence analysis of cement”.
In addition, the content of the trace element in the cement composition of the present invention is described in JIS R 5202 appendix 6. The cement composition of the present invention prepared according to the method described in “Preparation of cement sample” was obtained by measurement by mixed acid decomposition-ICP emission spectrometry using a mixed acid of nitric acid, hydrofluoric acid and perchloric acid. Value. More specifically, it refers to a value obtained by measurement by the method described in the examples described later.

The cement composition of the present invention preferably contains the above-described cement clinker of the present invention and gypsum.
The gypsum may be, for example, dihydrate gypsum, hemihydrate gypsum, anhydrous gypsum, and the like. In particular, anhydrous gypsum is preferable from the viewpoint of reactivity with the compound (mineral) contained in the clinker. The gypsum may be gypsum obtained from industrial waste such as flue gas desulfurization gypsum, titanium gypsum, which is a kind of dihydrate gypsum, and hydrofluoric acid anhydrous gypsum, which is a kind of anhydrous gypsum. One or more kinds of these gypsum may be used.

The cement composition of the present invention may further contain an admixture or an admixture.
Examples of the admixture include fly ash, silica fume, blast furnace fume, blast furnace granulated slag fine powder, expanded material, limestone fine powder, quick lime fine powder, dolomite fine powder, sodium bentonite, calcium bentonite, attapulgite, sepiolite, Examples include activated clay, acid clay, allophane, imogolite, shirasu (volcanic ash), shirasu balloon, kaolinite, metakaolin (calcined clay), synthetic zeolite, artificial zeolite, artificial zeolite, mordenite, and clinoptilolite.
Examples of the admixture include AE agent, water reducing agent, AE water reducing agent, fluidizing agent, separation reducing agent, setting retarder, setting accelerator, rapid setting agent, shrinkage reducing agent, foaming agent, foaming agent, waterproofing. Agents and the like.
One or a plurality of these admixtures and admixtures may be used.

The cement composition of the present invention may further contain an aggregate.
The aggregate may be one or both of known fine aggregate and coarse aggregate. Examples of the coarse aggregate include crushed stone, river gravel, natural lightweight coarse aggregate (perlite, leech stone, etc.), by-product lightweight coarse aggregate, artificial lightweight coarse aggregate, recycled aggregate, and the like. Examples of the fine aggregates include natural fine aggregates such as river sand, mountain sand, sea sand, natural lightweight fine aggregates (perlite, leech stone, etc.), crushed sand, artificial lightweight fine aggregates, blast furnace slag fine aggregates, etc. Artificial fine aggregate, by-product lightweight fine aggregate, and the like. One kind or a plurality of kinds of these fine aggregates and coarse aggregates may be used.

(Cement production method)
Next, the manufacturing method of the cement clinker and cement composition of this invention is demonstrated.

  The cement clinker of the present invention includes, for example, a raw material process for obtaining a clinker raw material by adjusting the blending ratio of various materials and blending the material, and a firing process for producing a cement clinker by firing the clinker raw material. Can be manufactured.

First, a clinker raw material is obtained by adjusting the blending ratio of various materials and blending the materials (raw material process). At this time, the blending ratio of various materials so that the ratio of C ₃ A, C ₄ AF, MgO, TiO ₂ , and MnO contained in the cement clinker to be manufactured is within the range included in the cement clinker of the present invention described above. Adjust as appropriate.

The various materials of the clinker raw material are not particularly limited, and can be used regardless of the form of element simple substance, oxide, carbonate or the like. Examples of the various materials include CaO sources such as limestone, quicklime and slaked lime, Al ₂ O ₃ sources such as silica and clay, Fe ₂ O ₃ sources such as iron cake and iron cake, and MgO sources such as limestone and clay. Can be used.
Among them, as the TiO ₂ source contained in the various materials of the clinker raw materials can preferably be used gypsum. As the MnO source contained in the above various raw materials, it is preferable to use slowly cooled slag, foundry sand and the like.
In addition, various materials of the clinker raw material may include incineration ash or the like as a source of the above-described trace elements such as Zn, Sr, Ba, Cu, and Li.

Moreover, as various materials of the clinker material, industrial waste, general waste, construction generated soil, or the like may be used.
Industrial waste includes, for example, blast furnace slag; coal ash; ready-made sludge, sewage sludge, purified water sludge, construction sludge, steel sludge, and other sludge; gypsum waste materials such as waste gypsum boats; boring waste soil, various incineration ash, castings Examples include sand, rock wool, waste glass, secondary ash in the blast furnace, construction waste, and concrete waste.
Examples of the general waste include sewage sludge dry powder, municipal waste incineration ash, and shells.
Examples of construction generated soil include soil and residual soil generated from construction sites and construction sites, and waste soil.

  The clinker raw material blended as described above can be mixed while being pulverized using, for example, a mill or the like and used in a subsequent firing step.

Next, the cement clinker of this invention is manufactured by baking this clinker raw material (baking process). The firing of the clinker raw material is not particularly limited, but can be performed by preheating the clinker raw material, firing in a firing furnace, and then cooling.
The firing can be performed using, for example, an electric furnace or a rotary kiln. When firing using a rotary kiln, the firing temperature at the time of firing may be, for example, 1200 ° C. or more and 1400 ° C. or less, and preferably 1300 ° C. or more and 1350 ° C. or less.

The cement composition of the present invention can be produced by a finishing process in which the cement clinker of the present invention thus obtained is further mixed with gypsum to form a mixed material and the mixed material is pulverized. The mixed material can be pulverized using, for example, a pulverizer such as a ball mill.
In addition, when mixing the said cement clinker and gypsum, you may further mix 1 type or multiple types of the above-mentioned admixture, admixture, and aggregate.

(Cement color tone adjustment method)
The cement clinker and the cement composition of the present invention can be suitably used for, for example, new concrete when jointing an existing concrete building. In that case, the color tone of the cement clinker and the cement composition is The color tone of the existing concrete is preferably as close as possible.
At this time, in producing the cement clinker or cement composition of the present invention, the b value in the Lab color space of the obtained cement clinker or cement composition can be obtained by adjusting the contents of TiO ₂ and MnO as the clinker raw material described above. The b value of the existing concrete can be adjusted to approach.

Specifically, the method for producing a cement clinker having an adjusted b value in the Lab space is a method for measuring the b value in the Lab color space of the existing concrete before the raw material step in the above-described cement clinker production method. The raw material process includes a raw material adjusting process for adjusting the TiO ₂ content and the MnO content of the clinker raw material based on the measured b value.

  First, in order to manufacture a cement clinker in which the b value in the Lab space is adjusted, the b value in the Lab color space of the existing concrete to be joined is measured (color tone measurement step). The b value of the concrete can be measured using a color / color meter.

Next, in the raw material step of adjusting the blending ratio of various materials and blending the materials, the TiO ₂ content and MnO content of the clinker raw material are adjusted based on the measured b value (raw material adjusting step). . Generally, when the content of TiO _{2 in} the clinker raw material is small and the content of MnO is large, the b value of the manufactured cement clinker becomes small. Similarly, when the content of TiO _{2 in} the clinker raw material is increased and the content of MnO is decreased, the b value of the manufactured cement clinker increases. Based on this, the TiO ₂ content and the MnO content of the clinker raw material are adjusted so that the b value of the cement clinker to be manufactured approaches the measured b value of the existing concrete to be joined. .
At this time, by adjusting the TiO ₂ content of the clinker material to 0.30 mass% or more and 0.94 mass% or less, and adjusting the MnO content to 0.10 mass% or more and 0.30 mass% or less. The b value of the obtained cement clinker can be adjusted to a range of 6-9.

More specifically, when the measured b value of the concrete to be joined is 6 or more and less than 7, the TiO ₂ content of the clinker raw material is preferably 0.34% by mass or more and 0.0. While adjusting to 69% by mass or less, the content of MnO may be adjusted to 0.11% by mass or more and 0.30% by mass or less, and more preferably, the content of TiO ₂ is 0.34% by mass or more and 0.0. The content of MnO may be not less than 0.25% by mass and not more than 0.30% by mass while being 54% by mass or less.
When the measured b value of the concrete to be joined is 7 or more and less than 8, preferably, the content of TiO ₂ of the clinker raw material is adjusted to 0.34 mass% or more and 0.94 mass% or less. In addition, the MnO content may be adjusted to 0.11% by mass to 0.30% by mass, and more preferably, the TiO ₂ content is 0.54% by mass to 0.73% by mass. At the same time, the MnO content may be set to 0.17 mass% or more and 0.25 mass% or less.
When the measured b value of the concrete to be joined is 8 or more and 9 or less, preferably the content of TiO ₂ of the clinker raw material is adjusted to 0.34 mass% or more and 0.94 mass% or less. In addition, the content of MnO may be adjusted to 0.11% by mass or more and 0.25% by mass or less, and more preferably, the content of TiO ₂ is 0.73% by mass or more and 0.94% by mass or less. At the same time, the MnO content may be 0.11% by mass or more and 0.17% by mass or less.

The method for adjusting the TiO ₂ content and the MnO content may be, for example, the above-described materials that serve as the TiO ₂ source and the MnO source so that the amount of TiO ₂ and MnO contained in the clinker material is within the above range. The method of mix | blending with these various materials is mentioned.

In addition to TiO ₂ and MnO, each component contained in the clinker raw material is variously produced in the cement clinker and cement composition to be manufactured, so that they are within the range of the cement clinker and cement composition of the present invention described above. The material may be adjusted as appropriate.

  The clinker material thus adjusted is fired by the above-described firing step, and the cement clinker of the present invention in which the b value of the Lab color space is adjusted based on the b value of the existing concrete to be joined. Can be manufactured.

  Furthermore, the cement clinker obtained in this way is a cement composition in which the b value in the Lab space is adjusted based on the b value of the existing concrete to be spliced by using the above-described finishing process as the cement composition. A composition can be produced.

As described above, the cement clinker of the present invention is 5% by mass to 15% by mass C ₃ A, 5% by mass to 15% by mass C ₄ AF, 0.79% by mass to 2.30% by mass. MgO, 0.30% by mass or more and 0.94% by mass or less of TiO ₂ and 0.10% by mass or more and 0.30% by mass or less of MnO, so that the b value in the Lab color space of the cement clinker is , 6 or more and 9 or less can be adjusted.

Similarly, the cement composition of the present invention has a C ₃ A of 4.5% by mass or more and 15% by mass or less, C ₄ AF of 4.5% by mass or more and 15% by mass or less, 0.71% by mass or more and 2.30%. Since it contains MgO of not more than mass%, TiO _{2 of not} less than 0.27 mass% and not more than 0.94 mass%, and MnO of not less than 0.09 mass% and not more than 0.30 mass%, the Lab color space of the cement composition It is also possible to adjust the b value in the range from 6 to 9.

At this time, by adjusting the amount of TiO ₂ and MnO contained in the cement clinker and cement composition of the present invention within the above range, the b value of the cement clinker and cement composition is within the range of 6-9. Can be adjusted in more detail.

  Hereinafter, the present invention will be clarified by giving specific examples and comparative examples of the present invention. In addition, this invention is not limited to a following example.

(Manufacture of cement clinker)
Each cement clinker of Examples 1-21 and Comparative Examples 1-6 was manufactured as follows using the following materials.
Silicon dioxide _(SiO 2): manufactured by Kishida Chemical Co., Ltd. iron oxide _{(III) (Fe 2 O 3} ) produced by Wako Pure Chemical Industries, Ltd. Calcium carbonate (CaCO _3): manufactured by Kanto Chemical Co., Inc. of aluminum oxide _{(Al 2 O} 3): manufactured by Kanto Chemical Co. Manufactured magnesium carbonate (MgCO ₃ ): Wako Pure Chemical Industries calcium sulfate (CaSO ₄ ): Kishida Chemical Co., Ltd. Manganese oxide (MnO): Kishida Chemical Co., Ltd. Strontium carbonate (SrCO ₃ ): Kanto Chemical Co., Ltd. Barium oxide (BaO) : Copper oxide (I) (Cu ₂ O): Kanto Chemical Co., Ltd.

Specifically, the composition of C ₃ S, C ₂ S, C ₃ A, and C ₄ AF calculated by the Borg formula in the cement clinker to be manufactured is a value generally shown in Table 1 below, and The amount of MgO, TiO ₂ , MnO, Sr component, Ba component, and Cu component contained in the cement clinker to be produced is adjusted so that the ratio is approximately the value shown in Table 1 below. Each clinker raw material which concerns on Examples 1-21 and Comparative Examples 1-6 was obtained by mix | blending each.

  Each obtained clinker raw material was put into an electric furnace and baked at 1450 to 1475 ° C. for 60 to 120 minutes. Next, the fired product was rapidly cooled to prepare cement clinkers of Examples 1 to 21 and Comparative Examples 1 to 6, respectively.

(Measuring method)
About each cement clinker of Examples 1-21 and Comparative Examples 1-6 produced in this way, each component contained in this cement clinker was measured as follows.

  First, JIS R 5202 Annex 6. According to the method described in “Preparation of cement sample”, a cement clinker sample for component measurement was prepared from the cement clinker.

Next, the amount of CaO, SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ actually contained in the obtained cement clinker sample was measured in accordance with JIS R 5204 “Method of fluorescent X-ray analysis of cement”, The compositions of C ₃ S, C ₂ S, C ₃ A, and C ₄ AF in the cement clinker were calculated based on the Borg equation. The results are shown in Table 1.

Similarly, the contents of MgO, TiO ₂ , MnO and SO ₃ actually contained in the cement clinker sample prepared as described above were measured in accordance with JIS R 5204 “Method for X-ray fluorescence analysis of cement”. The results are shown in Table 1.

  Furthermore, nitric acid (60 mass% aqueous solution, manufactured by Kanto Chemical Co., Ltd.) 5 ml, hydrofluoric acid (49.5 mass% aqueous solution, manufactured by Kanto Chemical Co., Ltd.) 3 ml and perchloric acid (60-62 mass% aqueous solution, manufactured by Kanto Chemical Co., Ltd.) ) After adding 0.5 to 1 g of the cement clinker sample prepared as described above to the mixed acid obtained by mixing 5 ml, the mixed acid was removed on the sand bath until the cement clinker sample was completely decomposed. Heated at ° C. After adding yttrium to the cement clinker decomposition solution thus obtained so that the yttrium concentration as an internal standard is 10 ppm, using “Varian 730-ES” manufactured by VARIAN, The ratio of Sr component, Ba component, and Cu component actually contained was measured by mixed acid decomposition-ICP emission spectroscopic analysis. The results are shown in Table 1.

  Further, the b value in the Lab color space of the cement clinker produced in this way was measured using “CR-400” manufactured by Konica Minolta. The measured b values for each cement clinker are shown in Table 1 below.

  As is apparent from Table 1, the cement clinker of Examples 1 to 21 in which the content of each component is within the range of the present invention had a b value in the Lab color space of 6 or more and 9 or less. In contrast, the cement clinker of Comparative Examples 1, 3, and 5 having a MnO content exceeding 0.30% by mass had a b value of less than 6. In addition, the cement clinker of Comparative Examples 2, 4 and 6 having an MgO content exceeding 2.30% by mass had a b value exceeding 9.

Moreover, when comparing the cement clinkers of Examples 1 to 6, Examples 7 to 12, and Examples 13 to 18, respectively, in the cement clinker included in the scope of the present invention, when the TiO ₂ content is relatively high, It can be seen that the b value of the cement clinker increases.
In addition, when the cement clinker of Examples 1-3 is compared, it can be seen that the cement clinker included in the scope of the present invention has a small b value of the cement clinker when the MnO content is relatively large.

Claims (4)

5 mass% to 15 mass% C ₃ A, 5 mass% to 15 mass% C ₄ AF, 0.79 mass% to 2.30 mass% MgO, 0.30 mass% to 0.94 A cement clinker containing TiO _{2 in a} mass% or less and MnO in a range from 0.10 mass% to 0.30 mass%.   Zn component of 0.10% by mass to 0.80% by mass, Sr component of 0.20% by mass to 1.0% by mass, Ba component of 0.10% by mass to 0.50% by mass, or 0. The cement clinker according to claim 1, further comprising one or more of Cu components in a range of 05 mass% to 0.25 mass%. 4.5 mass% to 15 mass% C ₃ A, 4.5 mass% to 15 mass% C ₄ AF, 0.71 mass% to 2.30 mass% MgO, 0.27 mass% A cement composition containing TiO _{2 in an} amount of 0.94 mass% or less and MnO in an amount of 0.09 mass% or more and 0.30 mass% or less.   0.09 mass% or more and 0.80 mass% or less Zn component, 0.18 mass% or more and 1.0 mass% or less Sr component, 0.09 mass% or more and 0.50 mass% or less Ba component, or 0.0. The cement composition according to claim 3, further comprising one or more Cu components of 045 mass% or more and 0.25 mass% or less.