Paste adhesive

Abstract

To provide a paste-like adhesive which is less likely to be solidified even when stored at high temperatures and can be stored for a long period of time.SOLUTION: There is provided a paste-like adhesive which is used for bonding a calcium silicate plate to a surface coated with an anticorrosive coating material, contains at least an inorganic fiber (excluding slag-wool) and does not solidify after 4 weeks of storage at 50°C. The paste-like adhesive does not solidify easily even when stored at high temperatures and can be stored for a long period of time. Moreover, the paste-like adhesive is less likely to cause dripping after application and thus has excellent application workability and high adhesive properties.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a paste adhesive, and more particularly to a paste adhesive for adhering a calcium silicate board to a surface coated with an anti-rust paint. [Background technology]

[0002] Conventionally, calcium silicate boards have been applied as fire-resistant coatings to steel H-beam or steel pipe columns. In this application, a packing material of the same quality is adhered to the steel frame for leveling. Considering that calcium silicate boards are alkaline, the adhesive used to adhere the calcium silicate boards is generally a paste-like adhesive whose main component is sodium silicate, such as water glass, mixed with various additives, such as inorganic fillers.

[0003] Such adhesives generally contain fibrous materials to reinforce them and improve application workability. For example, Patent Document 1 discloses a technology relating to a paste-like adhesive containing water glass as the main component and slag wool as a reinforcing material. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 51-31723 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the case of a paste-like adhesive containing sodium silicate and slag wool, as in Patent Document 1, the sodium silicate and slag wool solidify due to a so-called slag-alkali reaction, which makes it difficult to store the paste-like adhesive for a long period of time. In addition, when a thermal load is applied to the adhesive, the slag-alkali reaction is accelerated, which can make it difficult to store the adhesive for more than one week, especially in the summer. From this perspective, there has been a demand for an adhesive for bonding calcium silicate boards that is resistant to solidification even when stored at high temperatures and can be stored for long periods of time.

[0006] The present invention has been made in view of the above, and has an object to provide a paste adhesive that is resistant to solidification even when stored at high temperatures and can be stored for a long period of time. [Means for solving the problem]

[0007] As a result of extensive research into achieving the above object, the present inventors have discovered that the above object can be achieved by incorporating specific inorganic fibers, and have thus completed the present invention.

[0008] That is, the present invention includes, for example, the subject matter described in the following sections. Item 1 A paste-like adhesive for bonding calcium silicate boards, Contains at least inorganic fibers (excluding slag wool), A paste-type adhesive that does not harden even when stored at 50°C for 4 weeks. Section 2 Item 2. The paste adhesive according to Item 1, wherein the inorganic fibers are at least one type selected from the group consisting of carbon fibers and metal fibers. Section 3 Item 3. The adhesive according to item 1 or 2, wherein the value of the penetration D measured under the following measurement conditions is 20 mm or more. <Measurement conditions> The paste adhesive is stored in a sealed state at 50°C for four weeks, and then the paste adhesive is filled into a 650mL, 12cm deep container and placed on a horizontal surface in an environment of 15 to 30°C. A nail (length 125mm, diameter 4.2mm, mass 14g) is dropped onto the adhesive surface from a position 500mm above the adhesive surface in the container, and the length to which the nail penetrates the adhesive is measured; this measurement value is taken as the penetration depth D. Section 4 Item 4. The paste adhesive according to any one of items 1 to 3, which contains water glass. Section 5 Item 5. A paste adhesive according to any one of items 1 to 4, which is used to adhere a calcium silicate board to a surface coated with an anti-rust paint. [Effects of the Invention]

[0009] The paste adhesive of the present invention is resistant to solidification even when stored at high temperatures, and can be stored for long periods of time. DETAILED DESCRIPTION OF THE INVENTION

[0010]

[0023] In the present specification, the terms "contain" and "comprise" include the concepts of "contain," "comprise," "consist essentially of," and "consist only of."

[0011] The paste adhesive of the present invention is used for adhering calcium silicate boards. In particular, the paste adhesive of the present invention contains at least inorganic fibers (excluding slag wool) and does not solidify even when stored in an environment of 50°C for 4 weeks.

[0012] Because the paste-like adhesive of the present invention contains inorganic fibers, it is resistant to solidification even when stored at high temperatures, allowing for long-term storage. Furthermore, the paste-like adhesive of the present invention is resistant to dripping after application, providing excellent application workability, and also exhibiting high adhesive properties. Therefore, the paste-like adhesive of the present invention is suitable for use on calcium silicate boards, and is particularly suitable for bonding to surfaces coated with anti-rust paint.

[0013] The paste adhesive of the present invention is not particularly limited as long as it contains inorganic fibers (excluding slag wool), and may contain, for example, the same components as adhesives used to bond calcium silicate boards. For example, the paste adhesive of the present invention may contain a water-soluble silicate as an inorganic binder, particularly alkali silicate or colloidal silica, and among these, water glass such as sodium silicate, potassium silicate, or lithium silicate is preferred. When the paste adhesive contains water glass, it tends to have good adhesion to calcium silicate boards. The water glass is particularly preferably sodium water glass.

[0014] The method for producing the water-soluble silicate is not particularly limited, and for example, a water-soluble silicate produced by a known method can be used in the paste-like adhesive of the present invention. In addition, the water-soluble silicate can also be obtained as a commercially available product.

[0015] The inorganic fibers contained in the paste-like adhesive of the present invention can be selected from various inorganic fibers, except for slag wool, as long as the effects of the present invention are not impaired. Among them, at least one type selected from the group consisting of carbon fiber and metal fiber is preferred. In this case, the paste-like adhesive of the present invention is less likely to solidify even when stored at high temperatures and is less likely to drip after application. Carbon fiber is particularly preferred as the inorganic fiber.

[0016] The type of carbon fiber is not particularly limited, and a wide variety of known carbon fibers can be used, such as pitch-based carbon fibers, rayon-based carbon fibers, cellulose-based carbon fibers, polyacrylonitrile-based carbon fibers, vapor-grown carbon fibers, and graphitized fibers.

[0017] The structure of the carbon fiber is not particularly limited, and can be, for example, a fiber diameter of 10 to 25 μm, an average fiber length of 2 to 10 mm, and an aspect ratio of 150 to 450.

[0018] The type of metal fiber is not particularly limited, and examples thereof include a wide range of known metal fibers. Examples of metal fibers include fibrous materials made of various metals such as iron, such as steel wool, copper wool, and brass wool.

[0019] The structure of the metal fibers is not particularly limited, and may be, for example, a fiber diameter of 20 to 300 μm, an average fiber length of 1 to 10 mm, and an aspect ratio of 100 to 300.

[0020] The method for producing the inorganic fibers is not particularly limited, and for example, inorganic fibers produced by known methods can be applied to the paste-like adhesive of the present invention. In addition, inorganic fibers can also be obtained from commercial products, etc.

[0021] The paste adhesive of the present invention may further contain other components. Examples of other components include components that can be contained in conventional inorganic adhesives (particularly adhesives used for bonding calcium silicate boards). Specific examples of other components include fillers such as clay, wollastonite, and inorganic particles, as well as light stabilizers, antioxidants, preservatives, flame retardants, pigments, colorants, mildew inhibitors, and lubricants. One or more of these additives may be contained in the paste adhesive. From the viewpoint of easily achieving good adhesion and application properties, it is preferable that the other components contained in the paste adhesive of the present invention include one or both of clay and wollastonite. The paste adhesive of the present invention may consist essentially of the inorganic fibers, the water-soluble silicate (e.g., water glass), clay, and wollastonite, or may consist essentially of the inorganic fibers, the water-soluble silicate (e.g., water glass), clay, and wollastonite.

[0022] The paste adhesive of the present invention preferably does not contain a resin, and more preferably does not contain an organic material, in order to be less likely to solidify at high temperatures and drip after application. Even if the paste adhesive of the present invention contains a resin or organic material, the content thereof is preferably 5% by mass or less, more preferably 1% by mass or less, even more preferably 0.1% by mass or less, and particularly preferably 0% by mass, relative to the total mass of the paste adhesive.

[0023] Furthermore, it is also preferable that the paste adhesive of the present invention does not contain phosphoric acid or a salt thereof, since this makes it less likely to solidify at high temperatures and to drip after application.Even if the paste adhesive of the present invention contains phosphoric acid or a salt thereof, the content ratio thereof is preferably 5% by mass or less, more preferably 1% by mass or less, even more preferably 0.1% by mass or less, and particularly preferably 0% by mass, relative to the total mass of the paste adhesive.

[0024] In the paste adhesive of the present invention, the content ratio of each component is not particularly limited. For example, in order to prevent solidification at high temperatures and dripping after application, the content ratio of inorganic fibers relative to the total mass of the paste adhesive is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.2% by mass or more, and particularly preferably 0.3% by mass or more. For the same reasons, the content ratio of inorganic fibers relative to the total mass of the paste adhesive is preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 3% by mass or less, and particularly preferably 2% by mass or less.

[0025] Furthermore, in order to prevent solidification at high temperatures and dripping after application, the content of the water-soluble silicate (e.g., water glass) relative to the total mass of the paste adhesive is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 45% by mass or more, and particularly preferably 50% by mass or more. For the same reasons, the content of the water-soluble silicate (e.g., water glass) relative to the total mass of the paste adhesive is preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, and particularly preferably 55% by mass or less.

[0026] The paste adhesive of the present invention comprises a water-soluble silicate (e.g., water glass) and inorganic fibers, with the remainder being the other components described above, for example, the remainder being clay and / or wollastonite.

[0027] When the paste adhesive of the present invention contains clay, the content is preferably 15% by mass or more, more preferably 20% by mass or more, even more preferably 25% by mass or more, and particularly preferably 30% by mass or more, relative to the total mass of the paste adhesive. Also, when the paste adhesive of the present invention contains clay, the content is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less, relative to the total mass of the paste adhesive.

[0028] When the paste adhesive of the present invention contains wollastonite, the content thereof is preferably 5% by mass or more, and more preferably 10% by mass or more, relative to the total mass of the paste adhesive. Furthermore, when the paste adhesive of the present invention contains wollastonite, the content thereof is preferably 30% by mass or less, more preferably 25% by mass or less, and even more preferably 20% by mass or less, relative to the total mass of the paste adhesive.

[0029] The paste adhesive of the present invention, having the above-described configuration, does not solidify even when stored in a sealed state for 4 weeks in an environment at 50° C. Specifically, when 1500 g of the paste adhesive is sealed in a 1000 mL container, it does not solidify even after being stored in an environment at 50° C. for 4 weeks.

[0030] The paste adhesive of the present invention preferably has a penetration D value of 20 mm or more when measured under the following measurement conditions. <Measurement conditions> The paste adhesive is stored in a sealed state at 50°C for four weeks, and then the paste adhesive is filled into a 650mL, 12cm deep container and placed on a horizontal surface in an environment of 15 to 30°C. A nail (length 125mm, diameter 4.2mm, mass 14g) is dropped onto the adhesive surface from a position 500mm above the adhesive surface in the container, and the length to which the nail penetrates the adhesive is measured; this measurement value is taken as the penetration depth D.

[0031] Under the above measurement conditions, the nail is dropped so that the sharp end penetrates the adhesive surface. It is acceptable for the entire nail to be embedded in the adhesive upon dropping. Here, "storing the paste adhesive in a sealed state at 50°C for 4 weeks" can typically be achieved by sealing and placing 1500 g of the paste adhesive immediately after production or paste adhesive within 5 days of production in a 1000 mL container and storing this container in an environment at 50°C for 4 weeks. However, if the paste adhesive has been stored in a sealed state in an environment below 50°C immediately after production, "storing the paste adhesive in a sealed state at 50°C for 4 weeks" can be achieved by sealing and placing 1500 g of the paste adhesive within 3 months of production in a 1000 mL container and storing this container in an environment at 50°C for 4 weeks.

[0032] The value of the penetration D is preferably 40 mm or more, and 70 mm or less, in order to prevent solidification at high temperatures and dripping after application.

[0033] As described above, the paste adhesive of the present invention is resistant to solidification even when stored at high temperatures and can be stored for long periods of time because the penetration D is 20 mm or more, even after storing the paste adhesive in a sealed state at 50°C for 4 weeks. Moreover, the paste adhesive of the present invention is resistant to dripping even after application, so it has excellent application workability and also has high adhesiveness.

[0034] The paste adhesive of the present invention can be applied, for example, by applying 11 cm of the adhesive to a calcium silicate board. 3 When applied, 35,000mm 2 It can be spread over approximately 40,000mm 2 For example, the paste adhesive of the present invention can be applied to a lower acrylic plate in a thickness of 11 cm or more. 3 Then, an upper acrylic plate (same type as the lower acrylic plate) is placed over the adhesive, and a 500g weight is placed on the upper acrylic plate. When this is left for 1 minute, the adhesive spreads over an area of ​​2000mm. 2 In this case too, the paste adhesive of the present invention has excellent application workability.

[0035] Furthermore, the paste adhesive of the present invention is less likely to drip, and for example, even when applied to a calcium silicate board in a thickness of 5 mm or more, dripping is unlikely to occur.

[0036] The paste-like adhesive of the present invention can be used as an adhesive for calcium silicate boards, and is particularly suitable for adhering calcium silicate boards to surfaces coated with anti-rust paint. The calcium silicate and the surface coated with anti-rust paint are not particularly limited, and the paste-like adhesive of the present invention can be widely applied to surfaces coated with known calcium silicate and anti-rust paints.

[0037] The method for producing the paste adhesive of the present invention is not particularly limited, and for example, a wide range of known methods for producing paste adhesives can be adopted. [Example]

[0038] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

[0039] Example 1 A paste adhesive was prepared according to the formulation shown in Table 1. Specifically, a sodium silicate-based paste adhesive was obtained by mixing 51.5 parts by mass of sodium water glass as a water-soluble silicate, 0.5 parts by mass of "S-231" (fiber diameter 13 μm, average fiber length 3.3 mm, aspect ratio 250) manufactured by Osaka Gas Chemicals Co., Ltd. as carbon fiber, 34.9 parts by mass of clay, and 13.1 parts by mass of wollastonite.

[0040] Example 2 A paste adhesive was prepared according to the formulation shown in Table 1. Specifically, a sodium silicate-based paste adhesive was obtained by mixing 51.0 parts by mass of sodium water glass as a water-soluble silicate, 1.0 part by mass of steel wool (product number "BS-0"; thickness 0.3 mm or less, length 10 mm or less) obtained from Bonstar as metal fiber, 34.9 parts by mass of clay, and 13.1 parts by mass of wollastonite.

[0041] (Comparative Example 1) A paste adhesive was prepared according to the formulation shown in Table 1. Specifically, a sodium silicate-based paste adhesive was obtained by mixing 52.9 parts by mass of sodium water glass as a water-soluble silicate, 1.9 parts by mass of slag wool, 34.7 parts by mass of clay, and 10.0 parts by mass of wollastonite.

[0042] [Table 1]

[0043] Table 2 shows the results of evaluating the high-temperature storage stability (50°C, 4 weeks), adhesive spread area (application workability), dripping properties, and adhesion properties for each of the paste adhesives obtained in each Example and Comparative Example.

[0044] [Table 2]

[0045] Each evaluation was carried out by the following method.

[0046] (High temperature storage stability) 1500g of paste adhesive was sealed in a 1000mL container and stored in a 50°C environment for 4 weeks, after which the presence or absence of solidification was visually determined. If no solidification was visible, it was marked as "Good", and if solidification was visible, it was marked as "Poor". This was used to evaluate the high-temperature storage stability.

[0047] (Adhesive spread area (application workability)) The adhesives of Example 1, Example 2 and Comparative Example 1 were all stored at 50°C for 5 days, and then 11 cm of paste adhesive was applied to an acrylic plate (27 cm x 27 cm x 0.5 cm thick). 3 Take out the paste adhesive and place it on the top acrylic plate (320g, 27cm x 27cm = 729cm 2 A 500 g weight was placed on the upper acrylic plate for 1 minute, and then the area where the paste adhesive spread was measured.

[0048] (Drip-resistant) Paste adhesive is applied to a 20cm 2 After applying the adhesive to a calcium silicate board of 3mm, the applied surface was stood vertically and the thickly applied adhesive was evaluated for dripping. The thicknesses of the applied adhesive were 3mm, 5mm and 10mm, and the presence or absence of dripping was confirmed for each thickness.

[0049] (Adhesiveness) Apply paste adhesive at 1000g / m to a calcium silicate board (4cm x 4cm x 4cm thick). 2A quantity of 100g was applied to the calcium silicate plate, and an iron plate (7cm x 7cm x 0.3cm thick) coated with anti-rust paint was attached to the plate. An iron jig was then attached to the side of the calcium silicate plate that was not coated with the paste adhesive using an epoxy adhesive (trade name: Araldite, manufactured by Huntsman Japan) to create a test specimen. The adhesive strength of the iron jig of the test specimen was measured by pulling it with a universal testing machine, and the adhesive strength was found to be 0.098N / mm 2 Above this, mark "Yes", 0.098N / mm 2 If it was less than this, it was marked as "X".

[0050] Table 3 shows the results of measuring the penetration D of the paste adhesives prepared in each Example and Comparative Example under the following measurement conditions. Table 3 also shows the results of investigating whether each paste adhesive can be stirred. <Measurement conditions> The paste adhesives prepared in each Example and Comparative Example were stored in a sealed state at 50°C for 4 weeks, and then a 650 mL, 12 cm deep container containing the paste adhesive was placed on a horizontal surface in an environment of 15 to 30°C, and a nail (length 125 mm, diameter 4.2 mm, mass 14 g) was dropped onto the adhesive surface from a position 500 mm above the adhesive surface in the container. The length the nail penetrated into the adhesive was measured, and this measurement value was taken as the penetration depth D. In this measurement, the nail was dropped so that the pointed end pierced the adhesive surface.

[0051] For reference, Table 3 also shows the results of measuring the D value of the paste adhesive 1 week, 2 weeks, and 3 weeks after production.

[0052] [Table 3]

[0053] From the results in Tables 2 and 3, it was found that the paste adhesive obtained in the examples was resistant to solidification even when stored at 50°C for 4 weeks, and that it could be stored for a long period of time. In contrast, the paste adhesive obtained in the comparative examples was found to solidify after being stored at 50°C for 4 weeks. Furthermore, the paste adhesive obtained in the examples was found to solidify after being stored at 50°C for 4 weeks. 3 The value of the spread area also indicates that the coating workability is excellent, and even after coating, dripping hardly occurs and the adhesiveness is high.

Claims

1. A paste-like adhesive for bonding calcium silicate boards, Contains at least inorganic fibers (excluding slag wool), a water-soluble silicate, and a filler; the inorganic fiber is at least one selected from the group consisting of carbon fiber and metal fiber, The content of the inorganic fibers is 0.05% by mass or more and 10% by mass or less, The content of the water-soluble silicate is 30% by mass or more and 80% by mass or less, A paste-type adhesive that does not harden even when stored in a 50°C environment for 4 weeks.

2. 2. The paste adhesive according to claim 1, wherein the value of the penetration D measured under the following measurement conditions is 20 mm or more. <Measurement conditions> The paste adhesive is stored in a sealed state at 50°C for four weeks, and then the paste adhesive is filled into a 650 mL container with a depth of 12 cm and placed on a horizontal surface in an environment of 15 to 30°C. A nail (length 125 mm, diameter 4.2 mm, mass 14 g) is dropped onto the adhesive surface from a position 500 mm above the adhesive surface in the container, and the length to which the nail penetrates the adhesive is measured, and this measured value is taken as the penetration depth D.

3. A paste adhesive as described in claim 1 or 2, wherein the water-soluble silicate comprises water glass.

4. The paste adhesive according to any one of claims 1 to 3, which is used for adhering a calcium silicate board to a surface coated with an anti-rust paint.

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