JP2001040329A - Sealing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a seal material that resists the slide or distortion of flanges due to vibrations or thermal expansion by adding a silane compound or the like to at least either a first package prepared by mixing an end-blocked diorganopolysiloxane or the like with an NH2-containing compound and a second package containing a carbonyl-containing compound. SOLUTION: The first package is a mixture containing a diorganopolysiloxane or polyoxyalkylene polymer (A) that is blocked with hydroxyl groups on both ends and has a viscosity of 25-100 cSt at 25 deg.C and an organic compound (B) having at least one NH2 group, and the second package is a mixture containing component A and an organic compound (C) having at least one carbonyl group. A silane compound represented by the formula (wherein R1 and R2 are each a 1-6C monovalent hydrocarbon group) or a hydrolyzate thereof is added to at least either of the first and second packages. The two-package adhesive is filled into the gap between flanges and cured to form a thick film of the seal material in the gap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing method for sealing flanges of automobile parts such as oil pans, and more particularly, to forming a thick film of a sealing material in a gap between the flanges forming a sealing surface. It relates to a sealing method.
More specifically, the present invention relates to a sealing method in which a two-component mixed type condensed polysiloxane having a specific composition is used as a sealing material and the two components are mixed by a simple method so that the two components can be cured quickly and well to a deep portion.

[0002]

2. Description of the Related Art In an automobile part, it is necessary to seal the inside and the outside, that is, to prevent the inside liquid and gas from leaking to the outside or to prevent outside liquid, moisture and dirt from entering the inside. There are things you need. Such a seal is formed on a mating surface between a plurality of components such as a container and a lid for holding a liquid, a gas and the like inside. The mating surface is generally called a flange, and a sealing property is obtained by bringing the flanges into close contact with each other. The flange is often made of metal, plastic, etc., but the joint surface of the flange has fine irregularities, and in order to require reliable sealing, the flange surface must be polished and the mirror surface must be as smooth as mirror finish. Become. Since such surface treatment is not economical, it is general to improve the sealing performance by, for example, inserting a solid packing or gasket. The packing or gasket is formed by punching a rubber sheet, cork, cardboard, or the like into a substantially flange shape, and crushing the packing or gasket by the surface pressure of the flange, thereby increasing the degree of adhesion and improving the sealing property.

[0003] However, even if a solid packing or gasket is crushed by surface pressure, the sealing performance is insufficient. As a replacement method, a method in which a curable liquid material is applied to the flanges and the flanges are bonded to each other, and then the liquid material is cured, whereby fine irregularities on the flange surface can be covered to obtain a sealing property. This method is a well-known method called a so-called molded gasket (FIPG). The material of the in-situ molded gasket is also called a liquid gasket, and various materials such as a silicone resin, an acrylic resin, and a urethane resin are used. Among them, silicone resin is most preferably used because it is excellent in heat resistance, rubber elasticity, and chemical resistance and can obtain excellent sealing performance as a gasket material formed in situ.

In the above method, the gap between the flanges can be filled and adhered by the curable liquid gasket.
The fastening force for bonding the flanges can be reduced. The method of bonding the flanges is generally a method of fastening with bolts or screws, but by adopting the above method, the spacing between the bolts and screws is increased to reduce the number of parts and tightening torque. There is a merit that it can be done.

Further, in the above method, a clearance between two surfaces of the flanges that are closely adhered to each other is a clearance as small as the surface irregularities of the flanges, and an in-situ molded gasket material such as silicone existing between them becomes an ultrathin film. As described above, recent flanges reduce the number of fastening members such as bolts and screws. Therefore, when a large vibration or impact is applied to the flange, the mating surface of the flange may be shifted. In addition, a force that attempts to open also acts, which may cause the thin-film in-situ molded gasket to peel off from the flange and cause leakage. Further, when the flanges are made of different materials such as metal and plastic, deviations and distortions may occur between the flanges due to a difference in the coefficient of thermal expansion.

[0006] For the above reasons, as shown in FIG.
A method has been devised in which a groove is formed in the groove, the groove is filled with a liquid gasket, and the liquid gasket is applied to the joint of the flanges and bonded. In the figure, 42 is an oil pan,
Reference numeral 43 denotes a groove provided in a flange portion of the oil pan 42, and reference numeral 47 denotes a bolt hole for fastening the oil pan 42 to an engine block. In this method, the in-situ molded gasket formed in the groove, that is, the sealing material can relieve the stress and prevent the peeling of the sealing material due to distortion of the flange.

As another method for solving the above problem, a method of providing a clearance between the flanges is also conceivable. As a method of providing the clearance, there is a method in which a spacer serving as a spacer is sandwiched between the flanges, and a clearance corresponding to the thickness of the spacer is provided between the flanges. That is, the thickness of the sealing material for filling the clearance is required, and the thickness of the sealing material can reduce the distortion of the flange.

On the other hand, one-part condensation-curable silicone compositions containing an organopolysiloxane as a main component are very excellent in heat resistance, weather resistance, electric characteristics, etc., and are therefore used in automobile parts, electric / electronic parts and the like. Suitable as a material for in-situ molded gaskets. Numerous curing methods have been proposed, including a deacetic acid type, a deoxime type, a dealcohol type, a deacetone type, and the like, depending on the type of reaction.

[0009] However, since these are all of the type that reacts with the moisture in the air and cures gradually from the surface to the inside, the curing time is long, for example, it takes about 7 to 10 days to cure 10 mm, 20 mm It takes about one month to cure. Further, in the closed state, a longer curing time is required. In particular, for example, when forming a FIPG sealing material for an oil pan of an automobile engine, a test run (firing test) of the engine is performed within about one hour after application and sealing, so that almost only the surface is hardened. There was a risk of problems such as leakage. In addition, when used for bonding and fixing electric and electronic parts, it is almost used online, so it is necessary to ship it several hours after sealing,
There were inconveniences such as the need to be left overnight for hardening training.

In particular, when applied to a resin having a thick film, such as one in which a groove is formed in a flange, the moisture reaches the inside of the groove very slowly, and until the resin hardens depending on the position and depth of the groove. However, there are problems such as that it takes a considerable amount of time and does not cure. Further, even when applied to a flange provided with a clearance, there is a problem that the film does not harden to the inside because the film thickness of the sealing material becomes large.

In order to solve such a problem, there is a method of dividing a conventional composition into a main agent and a curing agent to form a two-part composition. In the two-part type, the reaction starts when mixed, and the entire composition is cured, so that the inside of the thick film inside the groove can also be cured. However, the two-part curing type silicone resin is a so-called addition-reaction type silicone obtained by an addition reaction between a siloxane having an unsaturated double bond such as a vinyl group and a siloxane having a hydrogen atom. There was nothing. If there is no adhesiveness, the sealing material peels off from the flange due to distortion of the flange, causing leakage, and there is a defect that the improvement of the sealing property cannot be fundamentally achieved.

Further, the conventional two-part mixed type silicone has a very small amount of the curing agent with respect to the main component, so that it is difficult to mix, and it is difficult to balance the main component and the curing agent for uniform curing. When the ratio changes, the pot life becomes extremely short, and there are drawbacks such as gelling during mixing, and so-called one-part type that cures from the surface without two-part curing, and its practicality is Almost never.

The applicant of the present invention has invented a method of forming a sealing material using a two-component condensation-curable silicone resin (Japanese Patent No. 2534135). This is a method for forming a sealing material using a two-component condensed polysiloxane, and is a silicone having adhesive properties.

[0014]

However, the above-mentioned technique is to harden to a deep portion where moisture hardly reaches by reducing the amount of the hardening agent used as much as possible. Therefore, in order to cure to a deep part where moisture does not reach, the amount of the hydrolyzable silane that is a curing agent must be strictly controlled. If the amount of the curing agent is too large, the deep curability will be poor, and if the amount of the curing agent is too small, the storage stability of the solution A will be impaired and not only the solution may be hardened or thickened during storage, but also the solution A When the liquid is mixed, the curing proceeds rapidly, so that there is a disadvantage that the pot life becomes extremely short. For this reason, there is a risk that the ink may be cured in the mixing chamber or at the discharge nozzle, and a cleaning device or the like must be attached, which not only increases the size of the device but also wastes materials. For this reason, it was necessary to make the mixing ratio of the two liquids accurate. However, in reality, it is difficult to keep the amount of the curing agent constant in several steps such as the composition manufacturing process and the mixing process. However, it was not easy to exhibit sufficient deep curability.

In the above technique, the concentration of the curing agent dispersed in the liquid A is diluted with the silanol of the liquid B. Therefore, sufficient stirring is required for mixing the two liquids, and the line coating is performed by an automatic coating machine. To do so, a special dynamic mixer was needed. The dynamic mixer used in the above technology has a rotor internally provided with a spiral groove and a plurality of longitudinal grooves engraved on the surface so as to cross each other, a nozzle is formed at the bottom part, and separately in the mixing chamber, and The two liquids are mixed by feeding substantially the same amount, and are discharged onto the sealing surface of the object to be coated. For this reason, when the silicone resin described in Japanese Patent No. 2534135 is used, the apparatus becomes large-scale, and a welding robot or the like is required for the application robot, so that the entire system becomes very large. Further, in the dynamic mixer of the above-mentioned patent, heat of mixing is generated in the rotor and the mixing chamber, causing gelation of the resin, and possibly hardening in the mixing chamber, the first agent and the second agent.
There is a problem in that uniform mixing cannot be performed depending on the balance between the liquid sending speed of the agent and the rotation speed of the rotor. An object of the present invention is to provide a method for forming a sealing material that is resistant to displacement or distortion of a flange due to vibration or thermal expansion.

[0016]

In order to achieve the above-mentioned object, the present invention provides a sealing method for sealing by joining a joining surface between opposed flanges of an automobile part or the like with a sealing material. A gap is provided, and a two-liquid type sealing material obtained by mixing the following first and second agents is filled in the gap, and the sealing material is cured, and the thickness of the sealing material is filled in the gap between the flanges. This is to form a film. In the first agent, at least (A) both ends of the molecular chain are blocked with hydroxyl groups, and the viscosity at 25 ° C. is 25 to
1,000,000 centistokes diorganopolysiloxane or polyoxyalkylene polymer, (C) a mixture comprising an organic compound having at least one NH ₂ group in one molecule, and a second agent comprising at least one (A) a diorganopolysiloxane or polyoxyalkylene polymer having both ends of molecular chains blocked with hydroxyl groups and having a viscosity at 25 ° C. of 25 to 1,000,000 centistokes; (D) at least one molecule per molecule; It is a mixture comprising an organic compound having a carbonyl group. One or both of the first agent and the second agent are represented by the following general formula (B): CH ₂ ＣＨCHSi (O—N ＝ CR
¹ R ² ) ₃ or a hydrolyzate thereof (wherein R ¹ R ² may have the same or different number of carbon atoms of 1 to 2)
6 monovalent hydrocarbon groups), the first agent does not contain the component (D), the second agent does not contain the component (C), and the components (C) and (D) Are selected such that their NH ₂ and carbonyl groups are reactive with each other. With this configuration, by mixing the first agent and the second agent, the mixture is cured by the presence of moisture in the air, and water is generated in a deep portion at the same time as the curing.
Since curing occurs not only from the surface but also from the inside, rapid curing and deep curing are greatly improved. Also, a gap is provided between the flanges, and a two-liquid mixed type sealing material is filled in the gap and cured to form a thick film of the sealing material in the gap between the flanges. The seal material is not broken or peeled off from the gasket, and even if a flange made of a different material is used, the seal material can be broken or peeled off from the gasket due to the distortion of the flange caused by the difference in thermal expansion coefficient. Absent.

Here, the gap can be formed by a groove provided on at least one flange joining surface, a clearance between the flanges, and a convex portion provided on at least one flange joining surface. The component (D) has a carbonyl group of 0.001 to 100 g per 100 g of the component (A).
1 formulated in a molar and qs, said component (C) is preferably NH ₂ groups is blended in an amount of 0.001 mole component (A) 100 g per. Further, claims 1 to
6. In the sealing method according to any one of Items 5, it is preferable that the first agent and the second agent are mixed at a ratio of 1: 1. With this configuration, the first agent and the second agent are in a ratio of 1: 1.
By mixing the same amount of each, it is possible to quickly and satisfactorily cure to a deep part. Furthermore, the first agent, the second agent
Since the amount of the agent is the same, the measurement can be performed easily.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The component (A) blended in the first and second parts used in the sealing method of the present invention is used as a base polymer, and at least one of diorganopolysiloxane and polyoxyalkylene is used. used. These base polymers need to be blocked with hydroxyl groups at both molecular chains. That is, due to the presence of this hydroxyl group,
The diorganopolysiloxane of the component (A) can be condensed with the component (B) described below to form a cured rubber elastic body.

The base polymer of the component (A) has a temperature of 25 ° C.
Is from 25 to 1,000,000 centistokes (cSt), preferably from 1,000 to 500,000.
00 centistokes, more preferably 10,000
~ 100,000 centistokes. When the viscosity is out of this range, problems such as difficulty in forming a cured rubber product having satisfactory properties and lowering of workability occur. Among the above-mentioned base polymers, examples of the diorganopolysiloxane include those having a main chain composed of a repeating unit of a siloxane bond. The silicon atom having a siloxane bond can have an unsubstituted or substituted monovalent hydrocarbon group or a phenyl group. Specifically, methyl group, ethyl group, propyl group, butyl group, cyclohexyl group, vinyl group, allyl group, phenyl group, tolyl group, benzyl group, phenylethyl group, or hydrogen atom of these groups is partially halogen. An atom, a group substituted by a cyano group, for example, a chloromethyl group, 3,
Examples thereof include a 3,3-trifluoropropyl group and a cyanoethyl group.

Further, among the above-mentioned base polymers, as the polyoxyalkylene polymer, the oxyalkylene unit constituting the main chain is represented by —CH ₂ CH ₂ O—, —CH _{2
CH (CH 3) O -,} - CH 2 CH (CH 2 CH 3) O-,
Examples thereof include —CH ₂ CH ₂ CH ₂ CH ₂ O— and the like. However, from the viewpoint of availability and price, in particular, the main chain is a —CH ₂ CH (CH ₃ ) O— unit. What is constituted is preferred. The oxyalkylene units constituting the main chain may be not only one kind but also two or more kinds of units. Such a polymer is hydrolyzed and polycondensed in the presence of moisture to form a cured rubber elastic body. The hydrolyzable silyl group is one in which at least one hydrolyzable group is bonded to a silicon atom, and as the hydrolyzable group, a carboxyl group, a ketoxime group, an alkoxy group, an alkenoxy group, an amino group, an aminoxy group, An amide group etc. can be illustrated. The number of these hydrolyzable groups bonded to the silicon atom is not limited to one, and two or three hydrolyzable groups may be bonded to the same silicon atom. Naturally, other organic groups may be bonded to the silicon atom to which these hydrolyzable groups are bonded. Examples of such organic groups include alkyl groups such as methyl group, ethyl group, and propyl group. Groups, cycloalkyl groups such as cyclohexyl groups, vinyl groups, alkenyl groups such as allyl groups, phenyl groups, aryl groups such as tolyl groups, or groups in which hydrogen atoms of these groups are partially substituted with halogen atoms, for example Examples thereof include a chloromethyl group and a 3,3,3, -trifluoropropyl group.

The component (B) has the general formula: CH ₂ ＣＨCHSi (O
-N = CR ¹ R ² ) ₃ is a vinyltridialkylketoxime silane or a hydrolyzate thereof, which acts as a crosslinking agent. In the formula, R ¹ R ² is a monovalent hydrocarbon group having 1 to 6 carbon atoms which may be the same or different,
Specific examples include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a cyclopentyl group and a cyclohexyl group in which R ¹ and R ² are bonded to form a tube.
Specific examples of the component (B) include vinyltri (butanoxime) silane, vinyltri (propanoxime) silane, vinyltri (pentanoxime) silane, vinyltri (isopentanoxime) silane, vinyltri (cyclopentanoxime) silane, and vinyltri (cyclohexanoxime). )
Examples thereof include silanes, which can be used alone or in combination with 2
More than one species may be used in combination.

The amount of component (B) is 2 to 10 parts by weight, preferably 3 to 10 parts by weight, per 100 parts by weight of component (A). If the amount is less than 2 parts by weight, a cured product having excellent elasticity and mechanical strength cannot be obtained. If the amount exceeds 10 parts by weight, the cured product becomes hard and brittle.

The organic compound having at least one amino group (hereinafter simply referred to as “amino group-containing organic compound”) of the component (C) to be blended in the first agent is described below in (D).
Water that reacts with the components and acts as a curing agent is generated deep in the composition. As such an organic compound, the following formula (I)

[0024]

Embedded image

Any compound having a reactive primary amino group that exhibits a reaction represented by the formula (wherein R is an organic group) can be used.
Examples thereof include amines such as methylamine, ethylamine, butylamine, ethylenediamine, and aniline; silane coupling agents such as γ-aminopropyltriethoxysilane; and polymers and oligomers having an NH ₂ group as a functional group having an NH ₂ group as a functional group. In the present invention, (D)
From the viewpoint of steric hindrance at the time of reaction with the components, particularly those in which the carbon atom at the α-position of the amino group is part of a primary, secondary or aromatic ring are preferably used. When the carbon atom at the α-position is a normal tertiary carbon atom, the reactivity with the carbonyl group is poor, and the desired effect may not be obtained. Further, these compounds need not be limited to one kind, and two or more kinds can be used.

The amount of the component (C) is such that the amount of the primary amino group is 0.00% per 100 g of the component (A).
The range is preferably 1 to 1 mol, particularly preferably 0.01 to 1 mol. If the amount is less than 0.001 mol, sufficient deep curability will not be exhibited, and if it exceeds 1 mol, the obtained cured product of the elastic body will not exhibit the desired physical properties.

The component (D) blended in the second agent is an organic compound having at least one carbonyl group in one molecule. As the carbonyl compound, any one can be used as long as it satisfies the above conditions and the carbonyl group exhibits the dehydration condensation reactivity represented by the above formula (I). Include ketones such as acetone, methyl ethyl ketone and acetophenone; esters such as ethyl acetate, butyl acetate, methyl propionate and butyl lactone; amides such as dimethylformamide, diethylacetamide and butyrolactam; acetic acid, propionic acid and benzoic acid. And silane coupling agents having carboxylic acid and carbonyl groups as functional groups, and various polymers and oligomers. From the viewpoint of effectively completing the dehydration-condensation reaction of the formula (I), the carbon atom at the α-position to the carbonyl group is preferably a primary or secondary carbon atom or a part of an aromatic ring. These carbonyl compounds can be used alone or in combination of two or more.

The amount of the component (D) is preferably in the range of 0.001 to 1 mol, particularly 0.01 to 1 mol, per 100 g of the component (A). If the amount is less than 0.001 mol, sufficient deep curability will not be exhibited, and if it exceeds 1 mol, the obtained cured product of the elastic body will not exhibit the desired physical properties.

The silicone composition used in the present invention does not require as strong stirring as a dynamic mixer, and stirring with a static mixer is sufficient. Here, the static mixer is a device in which elements for generating a turbulent flow are stacked in several stages in series, and mixing is performed by passing a liquid to be mixed into the elements. Since the static mixer is mixed and discharged by being pumped into the mixer by a pump or the like, no power is required for mixing, and the apparatus can be simplified. As the static mixer, those commonly used in the technical field of mixing are used. For example, JP-B-44-8290, JP-A-56
JP-A-118726, JP-A-58-11028, JP-A-62-27029, JP-A-63-267425, JP-A-1-164424, JP-A-2-86834, JP-A-4-193337, Kaihei 5-212259,
Those described in JP-A-9-299776 can be used.

A dynamic mixer is a mixer that rotates or vibrates a stirring blade or a stirrer by a power source to mechanically mix the stirring blades and the stirrers. In the present invention, strong mixing by a dynamic mixer is not necessary, but a dynamic mixer can also be applied since it is not cured by reaction heat. When a dynamic mixer is applied, the number of rotations of stirring and the like can be made smaller than that of a resin that required conventional stirring, so that the heat of stirring and the like can be reduced.

The composition of the present invention is obtained by mixing the first and second components in a ratio of about 1: 1 with a simple mixing device such as a static mixer to form a one-part, room temperature, fast-curing composition. Obtained as a product. However, the present invention is strictly 1: 1.
Therefore, the accuracy of the pump and the mixer may not be so high. In addition, various compounding agents can be added to the first agent or the second agent as long as the fast-curing property and the deep-curing property at room temperature are not hindered. For example, an organic tin ester, an organic tin chelate complex,
Condensation catalysts such as organic titanates, organic titanium chelate complexes, tetramethylguanidylpropyltrimethoxysilane, tetramethylguanidylpropyltrimethoxysilane, etc .; methyltrimethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, methyltriprol Storage stabilizers such as penoxysilane, vinyltripropenoxysilane, phenyltripropenoxysilane, methyltributanoxime silane, tetrabutanoxime silane, and methyltriacetoxysilane; sprayable silica, precipitated silica, titanium dioxide, oxidized Reinforcing fillers such as aluminum, quartz powder, carbon powder, talc and bentonite;
Basic fillers such as calcium carbonate, zinc carbonate, zinc oxide and magnesium carbonate; fibrous fillers such as asbestos, glass fiber, carbon fiber and organic fiber; coloring agents such as pigments and dyes; heat-resistant such as red iron oxide and cerium oxide Cold improver; rust preventive; adhesive improver such as γ-glycidoxypropyltriethoxysilane; liquid reinforcing agent such as reticulated polysiloxane comprising triorganosiloxane units and SiO ₂ units; If necessary, a predetermined amount thereof can be added.

In the present invention, since it is important that the component (C) and the component (D) react as shown in the above formula (I) to produce water as a deep curing agent, As the component (C) and the component (D), those capable of promptly causing such a reaction are of course selected and used, and various compounding agents optionally used also inhibit the generation of such water. Not used to be selected.

The composition of the present invention cures due to the presence of moisture in the air and, at the same time as the curing, produces water in a deep portion thereof.
Hardening also occurs from inside. Therefore, the rapid curability and the deep curability can be significantly improved.

In the present invention, the two-package condensed organopolysiloxane used as the sealing material is quickly mixed by mixing the two packs in the same amount of 1: 1.
The first agent and the second agent
The same amount metering of the agent, for example, to operate the servo motor,
This can be easily achieved by operating the buffer tank constantly. The first and second agents that have been fed are mixed uniformly and quickly by passing through a mixing device such as a static mixer. Therefore, even if the curing time of the sealing material is short, it hardens during mixing. There is no such thing. Therefore, the present invention has good workability and is applied online, and the mixture discharged from the tip of the nozzle is uniformly cured in a short time and well cured to the deep part. In the present invention, mixing with a static mixer or the like can be sufficiently used, but a dynamic mixer or the like cannot be used, and a dynamic mixer can be used if desired. In this case, the shape of the stirrer may be simple, and the stirring speed may be low, so that the apparatus can be simplified.

According to the present invention, there is provided a sealing method for sealing by joining a joining surface of opposed flanges of an automobile part or the like with a sealing material, wherein a gap is provided between the flanges.
The gap is filled with a two-liquid type sealing material obtained by mixing the following first and second agents, and is cured to form a thick film of the sealing material in the gap between the flanges. It is like that. By forming the sealing material between the flanges in a thick film, resistance to distortion between the flanges is provided. In order to form a thick film, a space for filling the sealing material composition is provided between the flanges. This gap is formed in a portion where the flanges are joined to each other,
The shape is not limited as long as the liquid gasket is filled. Further, the gap is preferably formed in an annular shape communicating with the flange, but is not limited thereto.For example, the gap is formed near the fastening member such as a bolt because distortion of the flange hardly occurs. It is not necessary.

A sealing method according to an embodiment of the present invention will be described with reference to the drawings. 1A to 1G are cross-sectional views showing examples of a gap formed between flanges of an automobile part or the like.

As shown in FIG. 1 (A), the gap is formed in a groove 5 having a substantially semicircular cross section provided on the joint surface of the lower flange 52.
3 can be formed. Further, as shown in FIG. 1 (B), it can be formed by a groove 56 having a rectangular cross section provided on the joint surface of the flange 55. In any case, by forming such a groove, a gap is formed in the groove when the upper flanges 51 and 54 are respectively covered. In this case, the depth and width of the groove can be appropriately changed depending on the shape of the flange used, the fastening force of the fastening member, the type of the object to be sealed, the pressure, the operating temperature, the operating environment, and the like. 1.5mm depth
It is preferable that the thickness is not less than 5 mm. However, even if the depth is deeper than 5 mm, the resistance to flange distortion is not so improved, and the sealing material is consumed unnecessarily.

As shown in FIGS. 1C and 1D, a gap may be formed between the flanges by forming projections 59 and 62 on the joint surfaces of the flanges. As shown, a gap may be formed by providing a notch 65 in the flange 64. In this case, the upper flanges 57, 60, 63 are respectively connected to the lower flanges 58, 61, 6
By making contact with 4, a gap is created between both flanges. Further, as shown in FIG. 1 (F), a gap may be formed by directly sandwiching the metal spacer 68 between the flat surfaces of the flanges 66 and 67 to form a clearance between the flanges.

Further, as shown in FIG. 1 (G), a metal spacer 71 may be sandwiched in the vicinity of the flat flanges 69, 70, and a clearance may be formed indirectly between the two flanges to form a gap. . If voids are formed with such clearance, the thickness should be at least 0.5 m
m or more is required, but if it is 1.0 mm or more, the resistance to flange distortion is further improved. But 3.0
If it exceeds mm, on the contrary, not only becomes unstable with respect to flange strain, but also a problem that chemical resistance and weather resistance deteriorate because the cross-sectional area of the sealing material increases, preferably from 0.5 mm to 3.0 mm, more preferably 1.
0 mm to 3.0 mm. In addition, the spacer to be used may be a plurality of pillar-shaped spacers arranged along the flange, or an annular spacer may be provided on the flange or on the inner peripheral side or outer peripheral side of the flange. A cylindrical member through which a fastener such as a bolt can be inserted may be provided.

[0040]

[Example] [Preparation of sample 1] 50 g of dimethylpolysiloxane having a viscosity of 30,000 cSt / 25 ° C, 0.05 g of dibutyltin octoate, and vinyltris (butanoxime) silane, in which both ends of the molecular chain were blocked with hydroxyl groups.
5 g, n-butylamine 4 g, zinc carbonate 25 g, and fumed silica 2.5 g were mixed in an anhydrous state to obtain a first agent.
Then, both ends of the molecular chain were blocked with hydroxyl groups, and the viscosity was 3
50 g of dimethyl polysiloxane of 000 cSt, 3.5 g of vinyltris (butanoxime) silane, 2 g of acetone, 0.05 g of dibutyltin dioctoate, 25 g of zinc carbonate, and 2.5 g of fumed silica were mixed in an anhydrous state to form a second agent. I got These were designated as Sample 1.

[Preparation of Sample 2] 50 g of dimethylpolysiloxane having a viscosity of 100,000 cSt / 25 ° C., both ends of which are blocked with hydroxyl groups, 3.5 g of vinyltri (methylethylketoxime) silane, 0.05 g of dibutyltin dilaurate, cyclohexyl A first agent was obtained by mixing 3 g of an amine, 50 g of calcium carbonate, and 2.5 g of fumed silica in an anhydrous state. Next, 50 g of dimethylpolysiloxane having a viscosity of 100,000 cSt and both ends of the molecular chain blocked with hydroxyl groups, 3.5 g of vinyltri (methylethylketoxime) silane, and 0.1 g of dibutyltin dilaurate.
05 g, cyclohexanone 3 g, calcium carbonate 50
g, 2.5 g of fumed silica in an anhydrous state
Agent was obtained. These were designated as Sample 2.

Example 1 JIS K was used as a test device.
The pressure vessel 10 shown in FIGS. 2A and 2B is similar to the flange pressure vessel for pressure test specified in 6820.
Was used to perform a pressure resistance test. The pressure vessel has an inner diameter of 58 m
An upper container 10a having an upper flange 11 having an outer diameter of 80 mm, an outer diameter of 80 mm and a height of 10 mm, and a lower container 10b having a lower flange 12 having the same dimensions as the upper flange. An annular groove 13 having a width of 3 mm and a depth of 3 mm is provided along the circumference at the center in the width direction of the surface (the surface to be brought into close contact with). The flange surface of the lower flange 12 was washed with toluene. Thereafter, the first agent and the second agent of Sample 1 prepared above were extruded and stirred by a static mixer, and the mixture was discharged from the discharge nozzle at the tip of the static mixer, and the groove 13 was filled with Sample 1. Sample 1 was discharged until the groove 13 was completely filled. Further, the above-mentioned sample 1 was applied to portions other than the grooves 13 on the flange surface of the lower flange. Immediately after the application, the upper container 10a is placed on the lower container 1a such that the upper flange 11 and the flange surface of the lower flange 12 are in contact with each other.
0b, and four fastening bolts 16 were assembled with a torque of 28 N · m. In the drawing, reference numeral 14 denotes a gasket in the groove 13, and reference numeral 15 denotes a gasket applied to a joint surface between the flanges 11 and 12.

After assembly, 30
It was left at room temperature for minutes. After 30 minutes, the four tightening bolts 16 were removed. Thereafter, the lower flange 12 was fixed, and this was vibrated at 30 Hz for 60 minutes using a vibration tester. Thereafter, the pressure test container was tightened with the four tightening bolts 16 at 28 N · m. A tube for injecting compressed air was connected to the pressure port of the pressure test container, and the pressure was raised at a rate of 0.1 kg / cm ² every 15 seconds to measure the pressure when air leaked.

Example 2 A pressure resistance test was performed in the same manner as in Example 1 except that Sample 2 was used instead of Sample 1.

[Example 3] JIS K was used as a test device.
The pressure vessel 2 shown in FIGS. 3A and 3B is similar to the flange pressure vessel for a pressure test specified in 6820.
Using 0, a pressure resistance test was performed. The pressure vessel has an inner diameter of 58
upper flange 21 mm, outer diameter 80 mm, height 10 mm
, And a lower container 20b having a lower flange 22 of the same size as the upper flange. A metal spacer 2 having a height of 21 mm is provided outside the lower flange.
After attaching 7, the flange surface of the lower flange 12 was washed with toluene. Thereafter, the upper container 20a is placed on the spacer 27 on the lower container 20b such that the flange surfaces of the upper flange 21 and the lower flange 22 face each other, and the four fastening bolts 26 are tightened with a torque of 28 Nm. Assembled. Since the spacer 27 is attached between the upper container 20a and the lower container 20b as described above, a clearance of about 1 mm exists between the flange surfaces of the upper flange 21 and the lower flange 22. The first and second components of Sample 1 prepared above were extruded and stirred by a static mixer, and the mixture was discharged from the discharge nozzle at the tip of the static mixer into the gap between the flange surface of the upper flange 21 and the flange surface of the lower flange 22. The above clearance was filled with Sample 1 by discharging. Then, by curing under the same conditions as in Example 1,
A gasket 24 having a thickness of about 1 mm was formed between the flanges.
Thereafter, under the same conditions as in the first embodiment, the lower flange 22
Were subjected to a vibration test.

Example 4 A pressure resistance test was performed in the same manner as in Example 3 except that Sample 2 was used instead of Sample 1.

Comparative Example 1 JIS K was used as a test device.
4 (a) and 4 (b), which are similar to the flange pressure vessel for pressure test specified in 6820.
Using 0, a pressure resistance test was performed. The pressure vessel has an inner diameter of 58
mm, outer diameter 80 mm, height 10 mm upper flange 31
, And a lower container 30b having a lower flange 32 of the same size as the upper flange. The flange surface of the lower flange 32 was washed with toluene. Thereafter, the first agent and the second agent of Sample 1 prepared above were extruded and stirred by a static mixer, and the mixture was discharged from a discharge nozzle at the tip of the static mixer, and Sample 1 was applied to the flange surface of the lower flange 32. Immediately after the application, the upper container 30a is placed on the lower container 30a such that the flange surfaces of the upper flange 31 and the lower flange 32 abut against each other.
b, and four fastening bolts 36 were assembled with a torque of 28 N · m. Then, vibration was applied to the lower flange 32 under the same conditions as in Example 1 to perform a pressure resistance test.

Comparative Example 2 A pressure resistance test was performed in the same manner as in Comparative Example 1 except that Sample 2 was used instead of Sample 1.

[Comparative Example 3] Using the apparatus of Example 1, instead of Sample 1, a two-component mixed addition type silicone (× XXX ×
XX) was used in the same manner as in Example 1 to perform a pressure resistance test. The two-component addition-type silicone is one that is polymerized by an addition reaction of a vinyl-containing siloxane and a hydrogen-containing siloxane.

Comparative Example 4 The following sample 3 was prepared as a liquid gasket. 5 parts of methyltributanooxime silane was added to 100 parts by weight of dimethylpolysiloxane having a viscosity of 20,000 cSt / 25 ° C., in which the molecular chain ends were blocked with hydroxyl groups, and the mixture was heated and stirred at 80 ° C. for about 3 hours. A polysiloxane blocked with tanoxime silane was synthesized. This methyldibutanooxime silane 90
A first agent was obtained by adding 10 parts by weight of fumed silica (R-972, manufactured by Nippon Aerosil Co., Ltd.) and 0.3 parts by weight of dibutyltin dilaurate to parts by weight and uniformly mixing under a nitrogen stream. Next, 10 parts by weight of R-972 was mixed with 90 parts by weight of dimethylpolysiloxane having a viscosity of 20,000 cSt / 25 ° C. in which the molecular chain ends were blocked with silanol, to obtain a second agent. Using the apparatus of Example 1, a pressure resistance test was performed in the same manner as in Example 1 except that Sample 3 was used instead of Sample 1.

[Comparative Example 5] Using the apparatus of Example 1, a one-liquid RTV silicone (××××××××××××××××××××××××××××××××××××××××××××××
215 (manufactured by XXX Corporation) was used in the same manner as in Example 1 to perform a pressure resistance test.

Table 1 summarizes the above withstand voltage test.

[0053]

[Table 1]

As shown in Table 1, in Comparative Examples 1 and 2, a liquid gasket was applied to the flanges and the bolts were tightened, whereby the flange surfaces were pressed against each other, and the liquid gaskets became a thin film sealing material between the flanges. In this state, when the bolts are removed by hardening, the flanges are bonded to each other by the sealing material, which is a cured product of the liquid gasket. However, the flange is easily separated from the sealing material by applying vibration. Further, in Comparative Examples 1 and 2, the composition having high adhesiveness was used, but it was considered that the relaxation of the stress between the flanges was not satisfied only by the thin film, and the peeling or the sealing material was broken.

Further, since the composition used in Comparative Example 3 had extremely low adhesiveness, it is considered that a peeled portion occurred even when a flange provided with a groove was used. In Comparative Example 4, there was no sufficient agitation, so that the curability in the groove was not sufficient, and in Comparative Example 5, the moisture did not reach the inside, so that the inside of the groove was not cured by curing for 24 hours. Even if a flange provided with a seal is used, it is considered that the flange is separated from the sealing material by applying vibration.

On the other hand, in Examples 1 to 4, the sealant filled in the groove or the clearance is hardened to the inside.
Since it also has adhesiveness, the sealing material, which is a cured product of the liquid gasket, does not peel off even in a severe vibration test with the bolts removed, and the bolts that are normally tightened at six locations during the pressure test are 4 High sealing performance has been achieved despite the fact that it was performed at only one place. From the above results, when the composition of the present invention is applied to a grooved flange, flange distortion due to vibration or thermal expansion, etc., even when a flange with few fastening parts such as bolts or a flange with weak fastening force is used. It can be understood that the reliability of the sealing performance is high.

[0057]

As described above, according to the present invention, a gap is provided between the flanges, and the two-component mixed type sealing material obtained by mixing the following first and second agents in the gap is filled. Then, this is cured to form a thick film of the sealing material in the gap between the flanges, so that the sealing material is not broken or peeled off from the gasket by vibration or impact, and the flange made of a different material is used. In the case where is used, a highly reliable sealing method can be provided without breaking the sealing material or peeling off from the gasket even with the strain of the flange caused by the difference in the thermal expansion coefficient.

Also, since the stress of the flange can be reduced,
The number of parts of the flange fastening members such as bolts and screws can be reduced. Further, since the tightening torque can be reduced, deformation of the flange and breakage of the bolt can be prevented.

The two-component sealing material used in the sealing method of the present invention is made of a specific composition as described above, and therefore has excellent fast-curing and deep-curing properties. It is suitable for a structure in which a is formed or a flange structure having a clearance.

Further, the sealing material of the present invention is obtained by mixing two liquids 1: 1.
Is a material that can be cured quickly and well to the depth by mixing it appropriately in the same amount, and because these two liquids do not require strong stirring, they can be homogenized by simple mixing means such as a static mixer. By mixing quickly and discharging onto the sealing surface of the object to be coated, workability is improved, application to an automatic coating line is facilitated, and production efficiency is improved.

[Brief description of the drawings]

1 (A) to 1 (G) are cross-sectional views showing various aspects of a gap formed between flanges of an automobile part or the like according to an embodiment of the present invention.

2A is a cross-sectional view of a test device used in an embodiment of the present invention, and FIG. 2B is a plan view of a lower flange of the test device in FIG.

3A is a cross-sectional view of a test device used in an embodiment of the present invention, and FIG. 3B is a plan view of a lower flange of the test device in FIG.

4A is a cross-sectional view of a test device used in a comparative example, and FIG. 4B is a plan view of a lower flange of the test device in FIG.

FIG. 5 is a perspective view showing an oil pan in which a groove is formed in a flange.

[Explanation of symbols]

11, 21, 31 Upper flange 12, 22, 32 Lower flange 13 Groove 14, 15 Liquid gasket 16, 26, 36 Fastening member 24 Liquid gasket applied to joint surface between flanges 21 and 22 27 Spacer 34 Gasket 42 Oil pan 43 Groove 47 Bolt hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) C08K 5/12 C08K 5/12 5/17 5/17 5/20 5/20 5/5425 5/5425 C08L 71/02 C08L 71/02 83/06 83/06 F16J 15/14 F16J 15/14 D (72) Inventor Tatsuya Kagosaki 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Omura Seiji 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Ryuji Shibata 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F term (reference) 4H017 AA04 AA25 AA27 AA31 AB16 AB17 AC16 AC19 AD02 AE05 4J002 CH02W CH02X CP06W CP06X EE038 EF038 EF098 EH038 EL068 EN027 EN037 EN067 EP018 EX016 EX038 EX076 EX077 FD146 FD147 FD148 GJ02

Claims (6)

[Claims] 1. A sealing method for sealing a joint surface between opposed flanges of an automobile part or the like by joining with a sealing material, wherein a gap is provided between the flanges, and the following first
A two-component type sealing material obtained by mixing the agent and the second agent is filled and cured to form a thick film of the sealing material in the gap between the flanges. A method for sealing automobile parts, wherein the first agent comprises (A) at least both ends of a molecular chain blocked with a hydroxyl group and a viscosity at 25 ° C of 25 to 1,000,000.
0 centistokes diorganopolysiloxane or polyoxyalkylene polymer, (C) a mixture comprising an organic compound having at least one NH ₂ group in one molecule, and a second agent comprising at least (A) molecules Both ends of the chain are blocked with hydroxyl groups and have a viscosity at 25 ° C of 25 to 1,000,000.
A mixture of a diorganopolysiloxane or polyoxyalkylene polymer having 0 centistokes and (D) an organic compound having at least one carbonyl group in one molecule. One or both of them are (B) a silane compound represented by the general formula: CH ₂ ＣＨCHSi (ON = CR ¹ R ² ) ₃ or a hydrolyzate thereof (wherein R ¹ R ² is the same or different The first agent does not contain the component (D), the second agent does not contain the component (C), and the component (C ) And component (D) are selected such that their NH ₂ and carbonyl groups are reactive with each other. 2. The sealing method according to claim 1, wherein the gap is formed by a groove provided on at least one flange joining surface. 3. The sealing method according to claim 1, wherein the gap is formed by a clearance between the flanges. 4. The sealing method according to claim 1, wherein the gap is formed by a convex portion provided on at least one flange joining surface. 5. The component (D) is added in an amount such that the carbonyl group is 0.001 to 1 mol per 100 g of the component (A), and the component (C) is an NH ₂ group containing 100% of the component (A).
2. The sealing method according to claim 1, wherein the amount is 0.001 to 1 mol per g. 6. The method according to claim 1, wherein the first agent and the second agent are mixed at a ratio of 1: 1.
The sealing method described in the section.