Joint, jointing method, and fluorine material

Abstract

To provide a joint body and a joint method of fluorine rubber and metal with stronger joint strength.SOLUTION: It is a composite of a base material and a fluorine material containing filler, and uses a composite in which the filler is acrylic particles. In addition, in the method of bonding the base material and the fluorine material containing filler, the filler contains acrylic particles, and when the fluorine material is peeled off from the base material, the method uses a bonding method that changes the propagation of cracks to the fluorine material side by the filler.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a bonded body, a bonding method, and a fluorine material. In particular, it relates to a bonded body and a bonding method of a base material and a fluorine material, and a fluorine material.

Background Art

[0002] Fluororubber has very high heat resistance and chemical resistance among rubbers, but on the other hand, it has a drawback that it is difficult to adhere. As an adhesion method, there is a method of adhering by a chemical effect using a primer or an adhesive. Also, there is a method of forming irregularities on the surface of the base material by chemical or laser etching and adhering by a physical effect (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional method, surface treatment of the base material, an adhesive, etc. were required. Therefore, an object of the present invention is to provide a bonded body and a bonding method of a fluorine material and a base material, and a fluorine material in which the bonding force (peeling force) is stronger regardless of the surface treatment of the base material, an adhesive, etc. That is, to provide a bonded body and a bonding method of a fluorine material and a base material, and a fluorine material in which the bonding force (peeling force) is stronger than before when the conditions such as the surface treatment of the base material and an adhesive are the same.

Means for Solving the Problems

[0005] To achieve the above object, the following invention is used. [Invention 1] A base material, A conjugate with a fluorine material containing filler 1, A conjugate in which the filler 1 is acrylic particles. [Invention 2] The filler 1 is, The conjugate according to Invention 1 having a thermal decomposition temperature higher than the temperature at the time of joining the fluorine material and the base material. [Invention 3] The filler 1 is a compound or polymer containing acrylic, the conjugate according to Invention 1 or 2. [Invention 4] The filler 1 is the conjugate according to any one of Inventions 1 to 3, containing one or more of methyl methacrylate, acrylic monomers such as methyl acrylate, and styrene. [Invention 5] The fluorine material is the conjugate according to any one of Inventions 1 to 4, containing any one or more of vinylidene fluoride, hexafluoropropylene, tetrafluoroethylene, vinylidene fluoride, perfluoromethyl vinyl ether, and MOVE monomer. [Invention 6] The particle diameter of the filler 1 is 1 to 100 μm, the conjugate according to any one of Inventions 1 to 5. [Invention 7] The fluorine material contains a polymer, The filler 1 is 1 to 80 parts by weight with respect to 100 parts by weight of the polymer, the conjugate according to any one of Inventions 1 to 6. [Invention 8] The fluorine material further contains filler 2, The filler 2 is not acrylic particles, the conjugate according to any one of Inventions 1 to 7. [Invention 9] The base material is the conjugate according to any one of Inventions 1 to 8, containing any one or more of resin and silicon. [Invention 10] Furthermore, it has an upper layer located on the surface of the fluorine material, The fluorine material is thicker than the diameter of the acrylic particles, The composition of the upper layer is different from the composition of the fluorine material, the conjugate according to any one of Inventions 1 to 9. [Invention 11] In a method for joining a fluorine material containing a base material and a filler, When peeling the fluorine material from the base material, a joining method in which the progress of cracks is changed to the fluorine material side by the filler. is used. [Invention 12] A fluorine material containing filler 1 which is acrylic particles. [Advantages of the Invention]

[0006] The joined body and joining method of the present invention are a joined body and joining method in which the bonding force between the fluorine material and the base material is strong. [Brief Description of the Drawings]

[0007]

Figure 1

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Embodiments for Carrying Out the Invention

[0008] The bonded body of the embodiment will be described. FIG. 1 shows a cross-sectional view of the bonded body 100 of the embodiment. The bonded body 100 is formed by bonding the base material 11 and the fluorine material 12. The fluorine material 12 contains a filler 14. The base material 11 is made of metal, ceramics, resin, etc. Metals include aluminum, silicon, titanium, chromium, iron, cobalt, nickel, molybdenum, copper, silver, gold, brass, and their alloys. Ceramics include alumina, zirconia, etc. Resins include polyimide, silicon, etc. (Claim 10).

[0009] The fluorine material 12 includes a polymer, a crosslinking agent, a crosslinking aid, and a filler 14. The polymer includes fluorine materials such as fluororubber and fluororesin. The types and amounts of the crosslinking agent and the crosslinking aid are selected according to the type of the polymer and the type of crosslinking.

[0010] Fluororesin is a general term for synthetic resins obtained by polymerizing olefins containing fluorine. It is characterized by high heat resistance, chemical resistance, and a small friction coefficient. Among them, the most mass-produced fluororesin is polytetrafluoroethylene <tetrafluoride resin>. For example, PTFE = polytetrafluoroethylene (tetrafluoride), PFA = tetrafluoroethylene·perfluoroalkyl vinyl ether copolymer, FEP = tetrafluoroethylene·hexafluoropropylene copolymer (4,6-fluoride), ETFE = tetrafluoroethylene·ethylene copolymer, PVDF = polyvinylidene fluoride (difluoride), PCTFE = polychlorotrifluoroethylene (trifluoride), ECTFE = chlorotrifluoroethylene·ethylene copolymer, etc.

[0011] Also, fluororubber is obtained by processing a partial fluororesin or a copolymer of fluororesin into a foam. For example, vinylidene fluoride-based (FKM), tetrafluoroethylene-propylene-based (FEPM), tetrafluoroethylene-perfluorovinyl ether-based (FFKM), etc. In the embodiment, both (fluororesin and fluororubber) are collectively referred to as a fluorine material.

[0012] For the filler 14, two types of fillers 1 and 2 can be used. Other fillers may be included as auxiliary. Filler 1 is acrylic-based particles. For example, it is three-dimensionally crosslinked acrylic particles with a volume average particle diameter of 6 μm, etc. Particles covered with acrylic may also be used. Particles with acrylic as the main component may also be used. As long as the particles have at least 50% volume or more of acrylic. A three-dimensionally crosslinked acrylic polymer composed of one or more of methyl methacrylate, methyl acrylate acrylic monomers, and styrene (Claim 4) is preferable. Fluoroacrylic may also be used.

[0013] Filler 2 is a particle other than an acrylic-based particle (Claim 9). That is, it is a particle that does not contain acrylic. For example, acetylene black having a number average primary particle diameter of about 30 nm or spherical carbon material of MT carbon having a particle diameter of about 280 nm can be used. The strength of the joined body can be reinforced by these particles. Among fillers 1 and 2, at least filler 1 is used. Only filler 1 may be used. As filler 1, acrylic particles are particularly good. As filler 2, carbon-based particles are good.

[0014] <Preparation of Fluorine Material 12> An example in the case of peroxide vulcanization is shown below. Any one of GBL-200S (manufactured by Chemours), GLT-200S (manufactured by Chemours), VPL-85540 (manufactured by Solvay), and SHP-86 (manufactured by Solvay) polymer (100 parts by weight), Peroxide-based crosslinking agent (0.4 parts by weight), Crosslinking aid isocyanurate trifunctional cyclic compound (1 part by weight), Fillers 1 and 2 (10 parts by weight each), are mixed and kneaded on a test roll with a roll diameter of 8 inches and a lateral roll length of 20 inches to produce a kneaded product. Unless otherwise specified, fluorine material 12 is composed of the above materials.

[0015] Here, peroxide vulcanization was used for the vulcanization system. Other vulcanizations may also be used. For the crosslinking agent and crosslinking aid, other appropriate amounts and suitable types can be used in addition to the above. The polymer is described as 100 parts by weight below.

[0016] <Joined Body> The base material 11 is set in a mold, a predetermined amount of the above kneaded product is put in, and press molding is performed under conditions of a predetermined temperature (160°C to 190°C) and a predetermined time (6 minutes to 10 minutes) suitable for various formulations (primary vulcanization). Then, secondary vulcanization is performed in an oven under conditions of 232°C for 10 hours. The temperature depends on the crosslinking agent and crosslinking aid, but is around 220 to 240°C.

[0017] <Test> After the secondary vulcanization, a 90° peel test of the fluorine material 12 and the base material 11 was performed using a tensile testing machine (model number AGS-X, manufactured by Shimadzu Corporation), and the adhesive strength was measured (JIS K6256-2). It can be said that when the peel strength is high, the bonding strength between the base material 11 and the fluorine material 12 is strong. Those with a peel strength of 1.5 times or more compared to the comparative example were considered qualified. This is because when the adhesive strength is improved by 1.5 times or more, it is considered that there is a sufficient significant difference rather than an error. Note that the comparison is made between those with the same conditions except for the filler 1 (examples and comparative examples). This is because the peel strength is affected by other conditions. The same applies to the following examples and comparative examples.

[0018] (1) Comparison of polymer types Examples 1-1 to 1-4 and Comparative Examples 1-1 to 1-4 were prepared with the compositions shown in Table 1 and subjected to a peel test.

[0019]

Table 1

[0020] (a) Base material 11 The base material 11 of 60 mm × 25 mm × 2 mm A-5052 aluminum alloy (hereinafter referred to as aluminum alloy) was washed with an alkaline cleaning solution DK Beaklear CW-7425 (10-fold dilution) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. Ultra-pure water was added to the beaker, the temperature was adjusted to 90°C with a hot stirrer, and the washed base material 11 fixed to the solution being stirred with a stir bar was immersed under the conditions of 90°C for 5 hours to subject the base material 11 to a boehmite treatment (treatment method 1).

[0021] Here, the boehmite method is a type of chemical conversion treatment for aluminum and aluminum alloys, which is a surface treatment that chemically forms an oxide film on the metal surface by the reaction of a chemical oxidant without electrolysis (electroless).

[0022] (b) Bonded body 100 The fluorine materials 12 (polymer, crosslinking agent, crosslinking aid, fillers 1, 2) shown in Table 1 were kneaded using a test roll with a roll diameter of 8 inches and a lateral roll length of 20 inches. Peroxide vulcanization was used. As the base material 11, the above-mentioned boehmite-treated base material 11 was used. The above kneaded product was combined with the base material 11 and vulcanized. The peel strengths obtained from the 90° peel tests are shown in Table 1. For the comparative examples, those with the same conditions except for the polymer were used to compare the peel strengths to determine pass or fail. For example, Example 1-1 was compared with Comparative Example 1-1. The same applies to the following examples.

[0023] (c) Polymer GBL-200S is a polymer composed of vinylidene fluoride, hexafluoropropylene, and ethylene tetrafluoride. (Claim 8) GLT-200S is a polymer composed of vinylidene fluoride, perfluoromethyl vinyl ether, and ethylene tetrafluoride. VPL85540 is a polymer composed of vinylidene fluoride, ethylene tetrafluoride, and a MOVE monomer. The MOVE monomer is a perfluorovinyl ether monomer. SHP-86 is a polymer composed of perfluoromethyl vinyl ether and ethylene tetrafluoride. These polymers are fluororubbers or perfluoroelastomers vulcanized by peroxide vulcanization. (Claim 7)

[0024] (d) Filler 14 As filler 2, acetylene black with a number average primary particle size of about 30 nm was used. Acetylene black is a carbon black produced by thermal decomposition of acetylene. It is of high purity and excellent in conductivity, and is used for conductivity and electrostatic prevention in fields such as raw materials for dry batteries, power cables, silicone products, and IC packaging materials. It is made of colloidal fine particles of carbon. As filler 1, three-dimensionally crosslinked acrylic particles (spherical) with a volume average particle size of 6 μm were used.

[0025] <Results> From Table 1, it can be seen that for all the polymers GLT-200S, GBL-200S, VPL85540, and SHP-86, the adhesive strength is improved by adding three-dimensional cross-linked acrylic microparticles. In the following examples and comparative examples, the description of the same conditions as above is omitted. Also, acrylic particles may be used instead of three-dimensional cross-linked acrylic microparticles. In particular, when the polymer GBL-200S is used, the peel strength is good.

[0026] (2) Types of Filler 2 Table 2 shows the results when Filler 2 is changed to MT carbon and Teflon (trademark) microparticles with respect to the composition in Table 1. Other conditions are the same as in (1). Note that Teflon (trademark) is polytetrafluoroethylene.

[0027]

Table 2

[0028] MT carbon is produced by thermal decomposition of natural gas and has less ash content and higher purity compared to carbon black produced by other manufacturing methods. Also, MT carbon has a relatively large particle size (100 - 700 nm) among carbon blacks. It is spherical microparticles with a number average primary particle size of 280 nm. Teflon (trademark) microparticles are microparticles with a volume average of about 12 μm.

[0029] From Table 2, it can be seen that not only acetylene black particles with a number average primary particle size of about 30 nm, but also MT carbon with a particle size of about 280 nm and Teflon (trademark) microparticles with a size of about 12 μm, when used together with acrylic particles, can significantly improve the adhesive strength. However, compared with the case of acetylene black in Example 1-1, the peel strength is smaller. Probably, as Filler 2, it is better to be smaller than Filler 1. Those with a particle size of 500 nm or less, and more preferably 280 nm or less are considered good. Preferably, it is 200 nm or less, and even better is 100 nm or less. It is considered that those that can easily fill the space between the spherical Filler 1 particles are good.

[0030] <Result> The bonding strength is not significantly affected by the type and size of filler 2. Filler 2 does not have to be carbon-based. Regarding the size of filler 2, there is no difference in peel strength when the particle size is 280 nm or 12 μm. However, a smaller particle size is preferred. Filler 2 can be up to 90 parts by weight, preferably up to 50 parts by weight, and more preferably up to 30 parts by weight.

[0031] (3) Characteristics of Filler 1 For the composition in Table 1, a sample (Comparative Example 3-1) was prepared with filler 1 being three-dimensional crosslinked acrylic fine particles with low heat resistance. Other conditions were the same as in (1). Note that each of FIG. 3 and FIG. 4 shows the results of differential scanning calorimetry of the three-dimensional crosslinked acrylic fine particles of Example 1-1 and the three-dimensional crosslinked acrylic fine particles of Comparative Example 3-1. The three-dimensional crosslinked acrylic fine particles added in Example 1-1 with a thermal decomposition temperature of 260 °C do not start thermal decomposition near the secondary vulcanization temperature of 230 °C. On the other hand, the three-dimensional crosslinked acrylic fine particles of Comparative Example 3-1 have a thermal decomposition temperature of 232 °C and start thermal decomposition near the secondary vulcanization temperature of 232 °C. Note that the thermal decomposition temperature is the inflection point of the heat flux, as indicated by the dotted lines in FIGS. 3 and 4, and is the point where the straight-line portions before and after the inflection point intersect.

[0032] Comparative Example 3-1 is shown in Table 3 together with Comparative Example 1-1 and Example 1-1. In the following examples, examples and comparative examples may be repeatedly used for comparison. From Table 3, it can be seen that for the three-dimensional crosslinked acrylic particles with a thermal decomposition start temperature (232 °C) below the secondary vulcanization temperature (232 °C) of the polymer in Comparative Example 3-1, the adhesive strength does not improve. When using three-dimensional crosslinked acrylic particles with a high thermal decomposition start temperature (260 °C) from Example 1-1, it can be seen that there is sufficient adhesive strength.

[0033]

Table 3

[0034] Fig. 5 and Fig. 6 show SEM images of the respective fillers 1 (three-dimensional crosslinked acrylic fine particles) remaining on the substrate 11 after 90° peeling of the samples of Comparative Example 3-1 and Example 1-1. It can be seen that the filler 1 of Comparative Example 3-1 shown in Fig. 5 is deformed and split in shape by thermal decomposition, while the filler 1 of Example 1-1 in Fig. 6 maintains its particle size and shape. Therefore, it is considered that the three-dimensional crosslinked acrylic particles added in Comparative Example 3-1 are thermally decomposed during the secondary vulcanization of the polymer (232 °C, 10 h), while the three-dimensional crosslinked acrylic particles added in Example 1-1 are not thermally decomposed.

[0035] <Results> The filler 1 added to improve the adhesive strength needs to be a filler having heat resistance that is not decomposed by heat during the secondary vulcanization of the polymer (Claim 2). In the case of fluororesin, it needs to be a filler that is not decomposed at the crosslinking temperature. That is, the filler 1 needs to be not decomposed at the temperature used when forming the joined body.

[0036] (4) Type of filler 1 For the compositions in Table 1, three-dimensional crosslinked fine particles of a copolymer of styrene and acrylic (volume average particle size 6 μm), urethane fine particles, polyethersulfone fine particles, crosslinked polystyrene, phenol fine particles, and polyimide fine particles were added as filler 1. The results are shown in Table 4. Other conditions are the same as in (1).

[0037]

Table 4

[0038] It can be seen from Table 4 that even if the filler is not composed only of acrylic particles, the adhesive strength is improved as long as acrylic is contained as a component. A polymer containing acrylic (Claim 3) or a copolymer containing acrylic is acceptable. On the other hand, in the case of urethane fine particles, polyethersulfone fine particles, crosslinked polystyrene, phenol fine particles, and polyimide fine particles, the peel strength was weak. These fillers are organic fillers composed of a composition that is not sufficiently decomposed by the heat of the secondary vulcanization of the polymer. Since their thermal decomposition temperatures are 320°C, 440°C, 280°C - 300°C, 300°C, and 380°C respectively, it is considered that they do not thermally decompose and are sufficiently higher than the secondary vulcanization temperature of the polymer. Therefore, there is no effect of thermal decomposition.

[0039] <Result> None of the heat-resistant organic fillers without acrylic showed an improvement in adhesion. Therefore, it can be seen that the composition of the filler containing acrylic contributes to the improvement of adhesion. As Filler 1, particles containing acrylic are good. This is presumably because the adhesion and bonding properties between acrylic and the polymer are good.

[0040] (5) Particle size of Filler 1 For Table 1, the results of the adhesion of Comparative Examples and Examples obtained from the 90° peel test of a fluorine material 12 and a substrate 11 in which three-dimensional cross-linked acrylic particles with volume-average particle sizes of 2.2 μm, 6 μm, and 46 μm were added to the polymer GBL-200S at 10 parts by weight are shown in Table 5. Other conditions are the same as in (1).

[0041]

Table 5

[0042] Figure 7 shows a graph of the particle size and the peel force. The peel force increases as the particle size is somewhat larger. However, if it is too large, the peel force becomes weak. The peel force is high in a wide range centered around the median value of 25 μm. It can be seen from Table 5 that the adhesion is sufficiently improved in the range of 2.2 μm - 46 μm for the particle size of the three-dimensional cross-linked acrylic particles.

[0043] <Result> The particle size of the acrylic particles is preferably 1 - 100 μm (Claim 5), more preferably 2 - 50 μm. 2 - 46 μm is preferred. The mechanism will be explained in the following <Cause of the improvement in bonding strength>. Since the acrylic particles control the cracks, it is effective in the wide range as described above.

[0044] (6) Addition amount of filler 1 For the composition in Table 1, the amount of acrylic particles of filler 1 was varied. The results are shown in Table 6. Other conditions are the same as in (1). A graph showing the relationship between the peel strength and the parts by weight of filler 1 is shown in Fig. 8. In Examples 6-5 to 6-7, the crosslinking agent and the crosslinking aid are changed to other examples. This is because the parts by weight of filler 1 are high and crosslinking needs to be strengthened. This has no effect on the peel strength.

[0045]

Table 6

[0046] From Table 6, an improvement in the adhesive strength can be seen by adding 1 part by weight or more of filler 1, and a greater adhesive strength can be obtained by further addition. From Fig. 8, the highest peel force is around 25 to 45 parts by weight of the median value.

[0047] <Result> The addition amount of filler 1 is preferably in the range of 1 part by weight to 80 parts by weight (Claim 6). The range of 5 parts by weight to 80 parts by weight is preferred. From Table 6, the value of the ratio of filler 2 / filler 1 is preferably 0.125 to 10. Including Table 7, the value of the ratio is preferably 0 to 10. By analogy, the value of the ratio is preferably 0 to 60.

[0048] (7) Addition amount in the case of only filler 1 For the composition in Table 1, examples were prepared in the case of only filler 1 without filler 2. Examples were prepared by varying the parts by weight of filler 1. The results are shown in Table 7. Other conditions are the same as in (1). Comparative Example 7-1 does not use filler 1 compared to Examples 7-1 to 7-8, and other conditions are the same. In Examples 7-7 to 7-8, the crosslinking agent and the crosslinking aid are changed to other examples. This is because the parts by weight of filler 1 are high and crosslinking needs to be strengthened. This has no effect on the peel strength.

[0049]

Table 7

[0050] Figure 9 shows a graph of the parts by weight of Filler 1 and the peel strength. The greater the parts by weight to a certain extent, the higher the peel strength. However, if it is too large, the peel strength becomes weak. The peel strength is the highest around 35 to 40 parts by weight of the median value, similar to the case of (6). Compared with the case of (6), the peel strength is slightly lower overall. It is preferable to have Filler 2 together with Filler 1. Even without Filler 2, the peel strength is improved.

[0051] <Result> For 100 parts by weight of the polymer, Filler 1 is preferably 1 to 80 parts by weight. A range of 5 to 80 parts by weight is preferable. It is considered that the same addition amount range is suitable even if fillers other than Filler 1 are included compared with (6).

[0052] (8) Various base materials and surface treatment (Treatment method 2: Blasting) For the base material 11 in Table 1, the surface treatment of the base material 11 and the type of the base material 11 were changed. The results are shown in Table 8. Note that an example without surface treatment is also included. Other conditions are the same as (1). As the surface treatment, blasting treatment (Treatment method 2) was used. Treatment method 2 is as follows. For the base material 11 of A-5052 aluminum with a size of 60 mm × 25 mm × 2 mm, unevenness was formed by sandblasting with a polishing agent of single crystal alumina #120. Then, it was washed with an alkaline cleaning solution DK Beak Clear CW-7425 manufactured by Daiichi Kogyo Seiyaku Co., Ltd. (10-fold dilution).

[0053]

Table 8

[0054] For each of the base materials 11 of A-5052 aluminum, C-2801 brass, SUS304, and polyimide with dimensions of 60 mm × 25 mm × 2 mm, unevenness was formed by sandblasting with abrasive agents of alumina #30, single crystal alumina #120, or brown alumina #220. After that, it was washed with an alkaline cleaning liquid DK Be clear CW-7425 manufactured by Daiichi Kogyo Seizo Co., Ltd. (10 times diluted). The same treatment as that for those without surface treatment was performed.

[0055] From Table 8, it can be seen that for various metals and various resins with various abrasive agents, the adhesive strength is improved by the addition of Filler 1 (three-dimensional cross-linked acrylic particles). Therefore, it was found that acrylic particles contribute to the improvement of the adhesive strength for metals and resins having any uneven structure. Since the adhesive strength is improved by the addition of acrylic particles for various metals and resins even without surface treatment, it was found that acrylic particles contribute to the improvement of the adhesive strength even on the surface of the smooth base material 11.

[0056] <Results> The type of the base material 11 and the surface unevenness of the base material 11 have little influence, and the bonding strength can be ensured by Filler 1 (acrylic particles).

[0057] (9) Constant base material, type of surface treatment Table 9 shows examples of cases where various surface treatments were performed with the material of the base material 11 being constant. First, the surface treatment will be explained. Other conditions are the same as those in (1). The unevenness on the surface of the base material 11 after the surface treatment is also shown at the bottom of Table 9.

[0058]

Table 9

[0059] Regarding the NMT (trademark) treatment (treatment method 3), A 60mm×25mm×2mm aluminum alloy substrate 11 was subjected to NMT treatment (Nano Molding Technology) by Daisheng Plus Co., Ltd. to form unevenness with a depth of about 20nm to 50nm. The NMT treatment involves immersing the metal in an alkali treatment, an acid treatment, and a T treatment (unique formulation solution) in sequence, followed by washing with water and drying to form a fine uneven shape.

[0060] NMT (trademark, Nano Molding Technology) can generate fine and complex unevenness on the surface of a metal through chemical conversion treatment, and utilize this unevenness to produce a composite molded product in which the metal and the resin are firmly joined. NMT is a technology that integrates by making fine and complex holes in the metal and performing insert molding. The NMT treatment can be applied to any material such as aluminum, iron, and stainless steel. The resin to be molded can be PPS, PBT, nylon, etc. The integration by bonding is different from the conventional manufacturing methods, and advantages such as rigidity, airtightness, heat transfer, light weight, and special shape can be expected in the design. Chemical conversion treatment generates fine and complex unevenness of 20 to 50 nanometers on the surface of the metal.

[0061] Regarding the DLAMP (trademark) treatment (treatment method 4), DLAMP is a technology for firmly bonding a metal and a dissimilar material by a completely dry process using a laser. After treating the metal surface with a laser and then pouring in the dissimilar material, a high bonding strength is achieved due to the anchor effect.

[0062] A 60mm×25mm×2mm aluminum alloy substrate 11 was subjected to DLAMP by Daicel Miraiz Co., Ltd. to form unevenness with a depth of about 0.1mm. DLAMP forms a complex shape on the surface of the metal by laser irradiation.

[0063] The NMT treatment (treatment method 3) of Daisin Plus Co., Ltd. or the surface treatment by DLAMP of Daicel Miraiz Co., Ltd. (treatment method 4) was applied to the base material 11 of A-5052. Table 9 shows the results of 90° peel of the samples in which the fluorine material 12 added with three-dimensional crosslinked acrylic particles was vulcanized and adhered to each base material 11. For comparison, the data in (8) are also shown in Table 9. Table 9 also shows the unevenness level after the surface treatment of the base material 11 measured by the method described below.

[0064] <Measurement of surface unevenness of base material 11> For the base material 11 of aluminum alloy, the surface roughness was measured and the surface shape image was obtained by using an atomic force microscope AFM5100N (controller AFM5000II, cantilever: SI-DF40P2) manufactured by Hitachi High-Tech Corporation under the conditions of a spring constant of 26 k (N / m), a resonance frequency of 200 to 400 kHz, a length of 160 μm, and a tip R of 10 nm or less for the base material 11 treated by boehmite treatment (treatment method 1), NMT treatment (treatment method 3), and the untreated base material 11.

[0065] For the base material 11 of aluminum alloy sandblasted with an abrasive of alumina #30, single crystal alumina #120, or brown alumina #220 (treatment method 2) and the base material 11 treated by DLAMP (treatment method 4), the surface roughness was measured at a magnification of 50 times by a 3D shape measuring machine VR-5200 manufactured by Keyence, and the surface state image was obtained.

[0066] Since the levels of unevenness are significantly different, they were measured with two types of measuring machines. Table 9 shows the measurement results of the average surface roughness (Sa), the height difference (Sz) which is the difference between the maximum and minimum values of the height, and the root mean square height (Sq) for the uneven structure of the base material 11, and their surface shape images are shown in FIGS. 10 to 16. FIGS. 10 to 12 were measured by AFM, and FIGS. 13 to 16 were measured by a surface shape measuring machine.

[0067] FIG. 10 shows the untreated base material 11, and FIG. 11 shows the NMT-treated base material 11. Figure 12 shows the boehmite-treated substrate 11, Figure 13 shows the brown alumina #220 sandblasted, Figure 14 shows the single crystal alumina #120 sandblasted, and Figure 15 shows the substrate 11 treated with brown alumina #30 sandblast, respectively. Figure 16 shows the DLAMP-treated substrate 11. The streaky unevenness of the substrate 11 without surface treatment in Figure 10 is the die mark formed during the extrusion in the production of aluminum (substrate 11).

[0068] <Adhesion and unevenness of substrates 11 with various surface treatments> Regarding the improvement in adhesion by adding filler 1 (three-dimensional cross-linked acrylic fine particles) to each uneven structure formed by each surface treatment on the above-mentioned A-5052 substrate 11, the following can be said from Table 9. From these results, it was found that at least when the average surface roughness (Sa) is 6.2 nm or more and 34.6 μm or less, the height difference (Sz), which is the difference between the maximum and minimum heights, is 74.6 nm or more and 410.0 μm or less, and the root mean square height (Sq) of the surface roughness is 7.8 nm or more and 43.9 μm or less, an improvement in adhesion can be seen by adding acrylic particles.

[0069] <Results> From the above, when the average surface roughness (Sa) is 1 nm or more and 100 μm or less, the height difference (Sz), which is the difference between the maximum and minimum heights, is 10 nm or more and 1000 μm or less, and the root mean square height (Sq) of the surface roughness is 1 nm or more and 100 μm or less, the effect of adding filler 1 occurs. Preferably, when the average surface roughness (Sa) is 6 nm or more and 35 μm or less, the height difference (Sz), which is the difference between the maximum and minimum heights, is 75 nm or more and 400 μm or less, and the root mean square height (Sq) of the surface roughness is 8 nm or more and 45 μm or less, an improvement in adhesion can be seen.

[0070] (10) Adhesion by primer Table 10 shows examples in which the fluorine material 12 was joined after applying a primer to the substrate 11 (treatment method 5). Other conditions are the same as in (1). In Examples 10-3 and 10-4, the type of polymer was changed.

[0071]

Table 10

[0072] As the base material 11, a base material 11 coated with a primer (vulcanization adhesive) was used. The base material 11 of an aluminum alloy with dimensions of 60 mm × 25 mm × 2 mm was cleaned with an alkaline cleaning solution DK Beak Clear CW-7425 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) (10-fold dilution). A solution obtained by diluting Metalock S-10A (manufactured by Toyo Chemical Laboratory) 2-fold with ethanol or diluting Monicas VD-300 (manufactured by Yokohama Polymer) 3-fold with 1,3-dioxolane was applied with a brush and left at room temperature for 15 minutes. Then, it was heated in an oven under the conditions of 155 °C for 30 minutes. Thereafter, the fluorine material 12 was joined.

[0073] <Results> From the results in Table 10, it can be seen that the adhesive strength is improved by adding Filler 1 (acrylic particles) for both types of primers. It was also found that the adhesive strength is improved by adding acrylic particles not only for the base material 11 having an uneven structure and the base material 11 without treatment but also for the base material 11 coated with a primer. The tendency was the same even when the type of polymer was changed. The fluorine material 12 has the same peel strength not only with respect to the base material 11 but also with respect to the primer. Metalock S-10A and Monicas VD-300 are fluororubber-based adhesives. For these fluororubber-based adhesives, the fluorine material 12 in this case is surely joined. It can be similarly applied to fluororesin-based adhesives.

[0074] (11) Upper layer 15 (Claim 11) Table 11 shows an example using the upper layer 15. FIG. 2 shows a cross-sectional view of the joined body 200 using the upper layer 15. The upper layer 15 is formed on the surface of the fluorine material 12. Other conditions are the same as those in (1).

[0075]

Table 11

[0076] 1: Pretreatment Before forming the upper layer 15 and the fluorine material 12, the surface of the substrate 11 was treated by the methods shown in the following (a) and (b). (a) As shown in treatment method 5, the aluminum alloy substrate 11 of 60 mm × 25 mm × 2 mm was washed with an alkaline cleaning solution DK BeClear CW-7425 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) (10-fold dilution), and then, as shown in treatment method 5, a solution obtained by diluting Metallock S-10A (manufactured by Toyo Chemical Research Institute) 2-fold with ethanol was applied with a brush, left at room temperature for 15 minutes, and then heated in an oven at 155 °C for 30 minutes.

[0077] (b) As shown in treatment method 1, the aluminum alloy substrate 11 of 60 mm × 25 mm × 2 mm was washed with an alkaline cleaning solution DK BeClear CW-7425 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) (10-fold dilution), ultrapure water was added to a beaker, the temperature was adjusted to 90 °C with a hot stirrer, and the washed substrate 11 fixed with a jig in the solution being stirred was immersed under the conditions of 90° for 5 hours to perform a boehmite treatment on the aluminum alloy substrate 11.

[0078] 2: Formation of upper layer 15 and fluorine material 12 The fluorine material 12 was formed on each of the substrates 11 surface-treated in the above (a) and (b). The upper layer 15 was formed thereon. The fluorine material 12 is a material to which 10 parts by weight of three-dimensional crosslinked acrylic fine particles are added, and the fluorine material 12 was formed with a thickness of 1 to 1.05 mm by press molding at 120 °C for 1 minute. The upper layer 15 was formed thereon. The composition is shown in Table 11. In Example 11-1, different fluorine materials were used for the upper layer 15 and the fluorine material 12. The thickness of the fluorine material 12 should be at least thicker than one acrylic particle. As explained in <Causes for improvement of adhesion> below, the presence of acrylic particles stops cracks at that part. As a result, peeling is less likely to occur.

[0079] Comparative Examples 10-1, 1-1, and 1-3 do not contain acrylic particles in the fluorine material 12 and do not form the upper layer 15. Examples 11-1, 11-2, and 11-3 contain acrylic particles in the fluorine material 12 and the upper layer 15 is formed. Table 11 shows the results of 90° peel. In Examples 11-1, 11-2, and 11-3 of the bonded body 200 containing the fluorine material 12 containing acrylic particles, the adhesive strength was significantly increased compared to the bonded bodies of Comparative Examples 10-1, 1-1, and 1-3. According to Examples 11-1 to 11-3, if there is a fluorine material 12 containing acrylic particles, the upper layer 15 does not necessarily need to contain acrylic particles. At least the composition of the upper layer 15 may be different from the composition of the fluorine material 12. The fluorine material 12 may be the fluorine material 12 of other examples. The upper layer 15 may be a resin system such as a silicon-based or polyimide-based system other than the fluorine material. Furthermore, as the upper layer 15, other base materials 11 can be used for bonding between the base materials 11.

[0080] <Results> If the fluorine material 12 with a thickness of 1 mm or more contains acrylic particles, the peel strength can be increased. Also, the thickness of the fluorine material 12 is preferably thicker than the diameter of the acrylic particles. As shown in the <Cause of Adhesive Strength Improvement> below, since cracks can be controlled by the acrylic particles, the thickness of the fluorine material 12 only needs to be thicker than the diameter of the acrylic particles. In this example, the fluorine material 12 is an adhesive (for adhesive use) used between the base material 11 and other materials.

[0081] (12) Adhesion by Type of Vulcanization Table 12 shows the case where the vulcanization is changed from peroxide vulcanization to polyol vulcanization. The polymer was changed to A-500 (manufactured by Chemours) for polyol vulcanization. A-500 is a polymer composed of vinylidene fluoride and hexafluoropropylene and is a polymer vulcanized by polyol vulcanization.

Table 12

[0082] The surface treatment of the base material 11 used single crystal alumina #120 sandblasting (treatment method 2). The fluorine material 12 of the polyol vulcanization was likely to bond to the base material 11 treated by the boehmite treatment (treatment method 1), but peeling occurred at the polymer part, and the peeling strength could not be measured. Thus, the treatment method was changed to treatment method 2 for the treatment of the base material 11. Similarly to the above, when acrylic particles were included, the peeling strength was improved.

[0083] <Results> From Tables 1 and 12, it can be seen that for all polymers of GLT-200S, GBL-200S, VPL85540, SHP-86, and A-500, regardless of the vulcanization system, the adhesive strength is improved by the addition of three-dimensional cross-linked acrylic fine particles. Regardless of the type of vulcanization, the bonding strength is improved by adding acrylic particles.

[0084] <Reason for the improvement of adhesive strength> In Patent Document 1, the adhesive strength is improved by the filler entering the unevenness. The cross-sectional SEM observation image of the bonded body 100 of Example 1-1 of the present embodiment is shown in FIG. 17. FIG. 17 is a cross-sectional photograph of the periphery of the interface between the fluorine material 12 and the base material 11. Since the acrylic particles (filler 1) are considerably larger than the boehmite treatment layer (pore diameter of several nm), it can be seen that they do not enter the pores of the boehmite treatment layer and are not mixed either. Therefore, it is considered that the adhesive strength is improved by a mechanism different from that of Patent Document 1.

[0085] When attempting to peel the fluorine material 12 from the base material 11 in this embodiment, cracks progress at the interface between the base material 11 and the fluorine material 12. However, when acrylic particles (filler 1) are present near the interface as shown in Fig. 17, the cracks no longer pass through the narrow part between the base material 11 and the fluorine material 12, new cracks are generated from the acrylic particles, and the cracks progress toward the polymer side. This can be seen in Fig. 18. Fig. 18 shows the surface of the fluorine material 12 after peeling it from the base material 11. It is in a stepped shape. That is, estimating from the peeling state at the interface, the cracks have migrated into the fluorine material 12. When the cracks progress toward the fluorine material 12 side, the cracks do not progress at the sites where the distance between the acrylic particles is narrow, and new cracks progress at the sites where the distance is wide. As the cracks progress toward the fluorine material 12 side, the steps are widely dispersed, causing the cracks to weaken and stop. For this reason, it is considered that the adhesive force increases.

[0086] This can be seen from the SEM image of the remaining polymer on the base material 11 after peeling the fluorine material 12 in Fig. 19. It can be seen that many acrylic particles are present near the steps, forming complex steps. Such a phenomenon is important because (a) the acrylic particles are hard and cracks do not progress inside the acrylic particles, and (b) the adhesiveness between the acrylic particles and the fluorine polymer is high and cracks do not progress at the interface between the acrylic particles and the polymer (it is considered that the adhesiveness is good because the acrylic resin and the polymer are compatible).

[0087] Also, the size of the filler 1 is considered important, and it is considered that acrylic particles with a size of about several micrometers are most suitable for causing cracks to progress toward the polymer side. When adding acrylic particles of a larger size with the same mass, the number of acrylic particles decreases, so the interface between the acrylic particles and aluminum or the gap between the acrylic particles becomes wider, resulting in less improvement in the adhesive force.

[0088] Also, when filler 1 is much smaller than several micrometers, the force that resists the progress of cracks increases. However, since the filler also moves during the progress of cracks, it is considered that the adhesive strength was not improved by adding only carbon (acetylene black) because the progress of cracks could not be prevented. If even higher adhesive strength is required, not only the acrylic particles of filler 1 but also the presence of carbon black (acetylene black) etc. as filler 2 is necessary. When carbon black is also used in combination, the polymer strength becomes stronger at the interface between the acrylic particles and aluminum or between the acrylic particles and acrylic particles, so that cracks cannot progress even in a wide gap.

[0089] Figure 20 shows the adhesive strength when acrylic particles (Acryl) as filler 1 and acetylene black (AB) as filler 2 are added to the polymer of GBL - 200S in a total of 30 parts by weight in various ratios. Acryl: 0 part by weight, AB: 30 parts by weight (comparative example) has 0% destruction on the polymer side, and the others (examples) are all destroyed on the polymer side (that is, the peel strength is large). Other conditions are the same as in Example 1 - 1.

[0090] When the acrylic particles are 0 part by weight and the acetylene black is 30 parts by weight, the adhesive strength is small, but when the acrylic particles are 30 parts by weight, the adhesive strength is large. When both are used in combination, the adhesive strength is even greater than that with only 30 parts by weight of acrylic particles. Figure 21 shows the SEM image of the broken part on the polymer side of the base material 11 after peeling of the sample in which the polymer was broken in the sample of Figure 20 (the following figure is an enlargement of the upper figure). Compared with the case where only acrylic particles are added, the cracks are more complex and steps are formed when used in combination. From this, it is considered that the adhesive strength is improved because cracks cannot progress even in a wide gap between acrylic particles. Filler 2 is preferably not acrylic particles. Destruction is prevented by physical properties different from those of acrylic particles between acrylic particles.

[0091] <Bonding method> From the above, in the present application, in the bonding method of the fluorine material 12 including the base material 11 and the filler 14, when the fluorine material 12 is peeled from the base material 11, it can also be said to be a bonding method (claim 12) that changes the progress of cracks to the fluorine material 12 side by the filler 14.

[0092] (As a whole) Examples in fluororubber were shown, but the same applies to fluororesin. The polymer only needs to contain a fluororesin or fluororubber as the main component, and other components may also be contained. Another filler may be contained in addition to the fillers 1 and 2. It is preferable that the fillers 1 and 2 are contained as the main component (1 part by weight or more). The fluorine material containing the filler 1 which is acrylic particles can also be used for other applications.

Industrial Applicability

[0093] The bonded body and bonding method of the present invention are used for bonding the fluorine material 12 and the base material 11. In addition, it can also be used for bonding silicon or the like to a base material.

Explanation of Symbols

[0094] 11 Base material 12 Fluorine material 14 Filler 15 Upper layer 100, 200 Bonded body

Claims

1. A bonded body comprising a base material and a fluorine material containing Filler 1, wherein Filler 1 is acrylic particles.

2. The bonded body according to Claim 1, wherein Filler 1 has a thermal decomposition temperature higher than the temperature at the time of bonding the fluorine material and the base material.

3. The bonded body according to Claim 1 or 2, wherein Filler 1 is a compound or polymer containing acrylic.

4. The bonded body according to Claim 1 or 2, wherein Filler 1 contains one or more of methyl methacrylate, acrylic monomers such as methyl acrylate, and styrene.

5. The bonded body according to Claim 1 or 2, wherein the fluorine material contains any one or more of vinylidene fluoride, hexafluoropropylene, tetrafluoroethylene, vinylidene fluoride, perfluoromethyl vinyl ether, and perfluorovinyl ether monomer.

6. The bonded body according to Claim 1 or 2, wherein the particle size of Filler 1 is 1 to 100 μm.

7. The bonded body according to Claim 1 or 2, wherein the fluorine material contains a polymer, and Filler 1 is 1 to 80 parts by weight with respect to 100 parts by weight of the polymer.

8. The bonded body according to Claim 1 or 2, wherein the fluorine material further contains Filler 2, and the above-mentioned Filler 2 is not acrylic particles.

9. The bonded body according to Claim 1 or 2, wherein the base material contains any one or more of resin and silicon.

10. Furthermore, it has an upper layer located on the surface of the fluorine material, the fluorine material is thicker than the diameter of the acrylic particles, and the composition of the upper layer is different from the composition of the fluorine material.

11. In a bonding method of a base material and a fluorine material containing a filler, the filler contains acrylic particles, and when the fluorine material is peeled from the base material, the progress of cracks is changed to the fluorine material side by the filler.

12. A fluorine material containing Filler 1 which is acrylic particles. ​ ​ ​ ​ ​ ​ ​ ​

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