Manufacturing method of laminate

Abstract

To provide a manufacturing method for a laminate which includes polysiloxane having lots of hydroxyl groups and has excellent moisture absorbency and scratch resistance.SOLUTION: A manufacturing method for a laminate includes: a coated-film forming step S2 of forming a coated-film composition by applying to a base substance a coating composition including a silane compound (I) and / or a derivative of the compound, which is represented by a general formula (I): R1aR2bSi(OR101)(4-a-b) (I), where in the formula (I), R1 is a hydroxyl group-containing hydrocarbon group in which δH concerning a Hansen solubility parameter satisfies a relational expression ofδH≥13, R2 is a monovalent hydrocarbon group, R101 is a hydrogen atom or a monovalent hydrocarbon group, a is an integer of 1 or 2, b is an integer of 0-2, and the sum of a and b is an integer of 3 or smaller, and then curing the coating composition by heating; and a post-processing step S3 of performing heating / humidifying processing to the coated-film composition.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a laminate. [Background technology]

[0002] In recent years, from the viewpoint of energy conservation, there has been a demand for anti-fogging technology that prevents condensation on components such as windows in vehicles such as automobiles, trucks, buses, and trains. In anti-fogging technology, a moisture-absorbing film is formed on a component such as a window, and moisture that would otherwise condense is absorbed into the moisture-absorbing film, thereby achieving anti-fogging.

[0003] Conventional moisture-absorbing films made of polymers with a carbon skeleton, such as cured epoxy resins and polyvinyl acetal resins, have poor scratch resistance. When solutions such as increasing the crosslink density or adding fillers are taken to improve scratch resistance, there is a problem that moisture absorption decreases.

[0004] Therefore, the inventors of the present application have focused on a moisture-absorbing film having a polysiloxane skeleton, and have proposed a laminate having a moisture-absorbing film that is excellent in both moisture absorption and scratch resistance, and a method for producing the same (Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] PCT / JP2021 / 2032 Summary of the Invention [Problem to be solved by the invention]

[0006] When a moisture-absorbing film having a polysiloxane skeleton is produced by a conventional method, a coating composition is prepared by first mixing a silane compound, which is a starting material, with an acid component to cause a hydrolysis reaction, and then applying the coating composition to a substrate surface and curing the coating composition by heating (e.g., baking) or by irradiating the substrate with light to form a moisture-absorbing film.

[0007] The silicon atoms that make up the polysiloxane skeleton are strongly oxygen-philic. Therefore, in conventional manufacturing processes, side reactions may occur in the polysiloxane skeleton during the process from the coating composition to the formation of a moisture-absorbing film. Specifically, this side reaction is, for example, a reaction in which an Si-O-C bond is formed between an Si-OH bond and a C-OH bond.

[0008] Although the laminate described in Patent Document 1 exhibited excellent performance, when the hydrophilic group is a hydroxyl group, it is thought that the hydroxyl group is consumed by the above-mentioned side reaction, which may reduce the moisture absorption performance of the moisture absorption film. If the hydroxyl group consumed in the side reaction can be regenerated, further improvement in moisture absorption can be expected in a moisture absorption film having a polysiloxane skeleton.

[0009] Therefore, an object of the present disclosure is to provide a method for producing a laminate that contains a polysiloxane that is rich in hydroxyl groups and has excellent moisture absorption and scratch resistance. [Means for solving the problem]

[0010] In order to solve the above problems, a method for producing a laminate disclosed herein is a method for producing a laminate having a substrate and a moisture-absorbing film formed on a partial surface of at least one side of the substrate, the method comprising: The following general formula (I): R 1 a R 2 b Si(OR 101 ) (4-a-b) …(I) [In formula (I), R 1 is a hydroxyl group-containing hydrocarbon group whose δH relating to the Hansen solubility parameter satisfies the relational expression δH≧13, R 2 is a monovalent hydrocarbon group, R 101 is a hydrogen atom or a monovalent hydrocarbon group, a is an integer of 1 or 2, b is an integer from 0 to 2, the sum of a and b is an integer of 3 or less.], and then applying a coating composition containing the silane compound (I) and / or its derivative to the substrate, and then curing the coating composition by heating to form a coating composition; and a post-treatment step of subjecting the coating composition to a heating and humidifying treatment.

[0011] According to this configuration, even when a silane compound (I) having a hydroxyl group-containing hydrocarbon group whose δH in terms of the Hansen solubility parameter satisfies the relational expression δH≧13 is used, i.e., a silane compound (I) having a structure that is prone to a side reaction such as the formation of an Si-O-C bond between an Si-OH bond and a C-OH bond, it is possible to regenerate the hydroxyl groups by subjecting the coating composition to a heating and humidifying treatment, thereby providing a laminate with excellent moisture absorption and scratch resistance.

[0012] The post-treatment step preferably involves heating and humidifying the film at a temperature of 40° C. or higher and a humidity of 95% RH or higher for one hour or longer.

[0013] According to this configuration, it is possible to regenerate hydroxyl groups more reliably and provide a laminate having excellent moisture absorption and scratch resistance.

[0014] In the formula (I), R 1 is preferably a hydroxyl group-containing hydrocarbon group having an organic chain represented by the following general formula (i):

[0015] [ka]

[0016] [In formula (i), n represents an integer of 1 to 10, * represents a carbon atom that may have a bond, and when one carbon atom having * is present in one molecule, that carbon atom is directly bonded to a silicon atom of the silane compound (I). When two or more carbon atoms having * are present in one molecule, any one of those carbon atoms is directly bonded to a silicon atom of the silane compound (I).

[0017] According to this configuration, although the silane compound (I) has a structure that makes the above-mentioned side reaction likely to occur, by subjecting the coating composition to a heating and humidifying treatment, it is possible to regenerate the hydroxyl groups, and therefore it is possible to provide a laminate having excellent moisture absorption and scratch resistance. [Effects of the Invention]

[0018] As described above, the present disclosure can provide a method for producing a laminate that contains a polysiloxane rich in hydroxyl groups and has excellent moisture absorption and scratch resistance. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a flowchart illustrating an example of a method for manufacturing a laminate according to the present disclosure. [Figure 2] 1 is a chemical reaction formula showing an outline of a reaction of a hydroxyl group-containing hydrocarbon group. [Figure 3] FTIR spectra of the coating composition and the laminate. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present disclosure, its applications, or its uses.

[0021] [Laminate] The laminate obtained by the manufacturing method of the present disclosure has a substrate and a moisture-absorbing film formed on at least a portion of at least one surface of the substrate. That is, the moisture-absorbing film may be formed on both or one side of the substrate, or on the entire or partial surface.

[0022] The substrate is not particularly limited as long as it can form a moisture-absorbing film. For example, the substrate may be made of an inorganic material, an organic material, or a composite material of an inorganic material and an organic material.

[0023] The inorganic material is not particularly limited and may be any inorganic material, such as glass, metal, ceramics, etc.

[0024] The organic material is not particularly limited and may be any thermosetting polymer and / or thermoplastic polymer. From the viewpoint of heat resistance when forming a moisture-absorbing film, a thermosetting polymer is usually used.

[0025] The thermosetting polymer may be any polymer having thermosetting properties, such as the following polymers and mixtures thereof: phenolic resin; Epoxy resin; melamine resin; and urea resin.

[0026] The thermoplastic polymer may be any polymer having thermoplastic properties, such as the following polymers and mixtures thereof: Polyolefin resins such as polyethylene and polypropylene, and their modified products; Polyester-based resins such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), and polylactic acid (PLA); Polyacrylate resins such as polymethyl methacrylate resin (PMMA); Polyether-based resins such as polyetheretherketone (PEEK) and polyphenylene ether (PPE); Polyacetal (POM); Polyphenylene sulfide (PPS); Polyamide resins (PA) such as PA6, PA66, PA11, PA12, PA6T, PA9T, and MXD6; Polycarbonate resin (PC); Polyurethane resins; Fluoropolymer resin; and Liquid crystal polymer (LCP).

[0027] From the viewpoint of heat resistance to baking during formation of the moisture-absorbing film, the substrate is preferably made of an inorganic material and / or a thermosetting polymer, and more preferably made of an inorganic material.

[0028] From the viewpoint of mechanical strength against cure shrinkage of the moisture-absorbing film, the substrate preferably has a Young's modulus of 1 GPa or more. There is no particular upper limit to the Young's modulus of the substrate.

[0029] In this specification, the Young's modulus is a value measured in accordance with ISO14577.

[0030] From the viewpoint of mechanical strength against cure shrinkage of the moisture-absorbing film, the substrate preferably satisfies the relational expression of substrate thickness / moisture-absorbing film thickness≧10, and more preferably satisfies the relational expression of substrate thickness / moisture-absorbing film thickness≧100.

[0031] The thickness of the substrate is usually 100 μm or more, preferably 500 μm or more, and more preferably 1000 μm or more. There is no particular upper limit to the thickness of the substrate, and the thickness of the substrate may be, for example, 10 cm or less.

[0032] [Silane compounds] The laminate obtained by the production method of the present disclosure starts from a coating composition containing a silane compound (I) represented by the following formula (I) and / or a derivative thereof.

[0033] R 1 a R 2 b Si(OR 101 ) (4-a-b) …(I) In formula (I), R 1 is a hydroxyl group-containing hydrocarbon group whose δH relating to the Hansen solubility parameter satisfies the relational expression δH≧13.

[0034] (Hansen solubility parameters) Hansen Solubility Parameters (HSP) (δ) are parameters that take into account the polarity (e.g., solubility) of a substance based on three components: the dispersion term (δD) (energy due to dispersion forces), the polar term (δP) (energy due to dipole-dipole interactions), and the hydrogen bond term (δH) (energy due to hydrogen bonds). 2 =(δD) 2 +(δP) 2 +(δH) 2 " relationship.

[0035] In the present disclosure, in the process from the coating composition to the formation of a moisture-absorbing film, the hydroxyl group-containing hydrocarbon group R 1 The δH of the silane compound was used as an index of the likelihood of a side reaction in which a Si-O-C bond is formed between a Si-OH bond and a C-OH bond. The researchers discovered that the above-mentioned side reaction is likely to occur when the hydroxyl-containing hydrocarbon group of the silane compound satisfies the Hansen solubility parameter δH≧13. They also discovered a manufacturing method that can produce a laminate with excellent moisture absorption and scratch resistance, even when using a silane compound that is prone to such side reactions.

[0036] Hydroxyl-containing hydrocarbon group R 1Specifically, the δH relating to the Hansen solubility parameter of the hydroxyl-containing hydrocarbon compound is used, in which the bond to the silicon atom in the hydroxyl-containing hydrocarbon group is bonded to a hydrogen atom instead of the silicon atom. Note that in the hydroxyl-containing hydrocarbon group, the atom bonded to the silicon atom in the siloxane skeleton is a carbon atom. The δP and δH relating to the Hansen solubility parameters of such hydroxyl-containing hydrocarbon compounds are calculated using the following conditions (PC software: HSPiP (Hansen Solubility Parameters) ver. 5).

[0037] A hydroxyl-containing hydrocarbon group is a hydrocarbon group containing a hydroxyl group (-OH). A hydroxyl-containing hydrocarbon group is a side chain group (particularly the entire group) directly bonded to a silicon atom. When a silane compound has a hydroxyl group in the form of a hydroxyl-containing hydrocarbon group with a specified δH in terms of the Hansen solubility parameter, a side reaction in which an Si-OC bond is formed between an Si-OH bond and a C-OH bond is likely to occur during the condensation reaction that produces a coating composition upon baking. However, when the hydroxyl group is regenerated in the polysiloxane skeleton obtained by the condensation reaction, such a hydroxyl-containing hydrocarbon group can exhibit excellent moisture absorption.

[0038] In formula (I), R 1 is preferably a hydroxyl group-containing hydrocarbon group having an organic chain represented by the following general formula (i):

[0039] [ka]

[0040] In formula (i), n is an integer of 1 to 10, * represents a carbon atom which may have a bond, and when one carbon atom having * is present in one molecule, that carbon atom is directly bonded to a silicon atom of silane compound (I). When two or more carbon atoms having * are present in one molecule, any one of those carbon atoms is directly bonded to a silicon atom of silane compound (I).

[0041] Hydroxyl-containing hydrocarbon group R 1 Table 1 shows specific examples (i-1), (i-2), and (i-3) of the above and their ΔH values ​​related to the Hansen solubility parameters.

[0042] [Table 1]

[0043] In Table 1, * denotes a carbon atom that may have a bond, and the carbon atom is bonded to the silicon atom of silane compound (I). For example, the hydroxyl-containing hydrocarbon groups (i-1), (i-2), and (i-3) are prone to a side reaction in which an Si-O-C bond is formed between an Si-OH bond and a C-OH bond during a condensation reaction. Therefore, a silane compound having a hydroxyl-containing hydrocarbon group that satisfies the Hansen solubility parameter δH≧13 is preferred as a starting material for the production method of the present disclosure, and more preferably a hydroxyl-containing hydrocarbon group such as (i-1) that further has an organic chain represented by the above general formula (i).

[0044] In formula (I), R 2 is a monovalent hydrocarbon group. 2 is a monovalent saturated aliphatic hydrocarbon group or a monovalent aromatic hydrocarbon group, and more preferably a hydrogen atom or a monovalent saturated aliphatic hydrocarbon group. 2 If the R 2 may each be independently selected.

[0045] In formula (I), R 101 is a hydrogen atom or a monovalent hydrocarbon group. 101 is a hydrogen atom, a monovalent saturated aliphatic hydrocarbon group, or a monovalent aromatic hydrocarbon group, and more preferably a hydrogen atom or a monovalent saturated aliphatic hydrocarbon group. 101 If the R 101 may each be independently selected.

[0046] In formula (I), a is an integer of 1 or 2, and from the viewpoint of further improving moisture absorption and scratch resistance, it is preferably 1. b is an integer of 0 to 2, and from the viewpoint of further improving moisture absorption and scratch resistance, it is preferably an integer of 0 to 1, more preferably 0. The sum of a and b is an integer of 3 or less (particularly 1 to 3), and from the viewpoint of further improving moisture absorption and scratch resistance, it is preferably an integer of 2 or less (particularly 1 or 2), more preferably 1.

[0047] The derivatives of silanes having a hydrophilic group-containing hydrocarbon group include silane oligomers such as dimers (i.e., disiloxanes) of the above-mentioned silane compound (I). Specifically, the dimers of the silane compound (I) are usually those of the above-mentioned silane compound (I) in which the OR in one molecule is 101 It is a disiloxane formed by dehydration condensation of two molecules of a silane compound (I) in which the number of groups (i.e., "4-ab") is an integer of 1 or more, particularly an integer of 2 or more (i.e., 2 or 3) (preferably 3).

[0048] The silane compound (I) having a hydrophilic group-containing hydrocarbon group includes, for example, disiloxane (I') represented by the following general formula (I').

[0049] R 1 a R 2 b Si(OR 101 ) (3-a-b) -O-Si(OR 101 ) (3-a-b) R 1 a R 2 b …(I') In formula (I'), R 1 represents R in the general formula (I). 1 The preferred R 1 is a preferred R in the general formula (I). 1 The same applies to disiloxane (I'). 1 If the R 1 may each be independently selected.

[0050] In formula (I'), R2 is R in the general formula (I). 2 The preferred R 2 is a preferred R in the general formula (I). 2 The same applies to disiloxane (I'). 2 If the R 2 may each be independently selected.

[0051] In formula (I'), R 101 represents R in the general formula (I). 101 The preferred R 101 is a preferred R in the general formula (I). 101 The same applies to disiloxane (I'). 101 If the R 101 may each be independently selected.

[0052] In formula (I'), a is an integer of 1 or 2, and from the viewpoint of further improving moisture absorption and scratch resistance, it is preferably 1. b is an integer of 0 to 2, and from the viewpoint of further improving moisture absorption and scratch resistance, it is preferably an integer of 0 to 1, more preferably 0. The sum of a and b is an integer of 3 or less (particularly 1 to 3), and from the viewpoint of further improving moisture absorption and scratch resistance, it is preferably an integer of 2 or less (particularly 1 or 2), more preferably 1.

[0053] The silane compound (I) and its derivatives are commercially available or can be produced by known methods.

[0054] An example of a commercially available silane compound (I) is alkylene glycol silane (trade name "X-12-1098" manufactured by Shin-Etsu Chemical Co., Ltd.) Alkylene glycol silane ("X-12-1098" manufactured by Shin-Etsu Chemical Co., Ltd.) is a compound belonging to silane derivatives having a hydroxyl group-containing hydrocarbon group, and is a disiloxane compound.

[0055] In this specification, hygroscopicity refers to the property of a hygroscopic film that can absorb liquid or gaseous water. Hygroscopicity also includes anti-fogging property. Anti-fogging property refers to the property of preventing condensation of water by absorbing liquid or gaseous water into a hygroscopic film.

[0056] In this specification, scratch resistance refers to the property of being difficult to scratch due to high hardness.

[0057] [Paint composition] The coating composition used in the manufacturing method of the present disclosure contains the silane compound (I) and / or its derivative, and may also contain other silane compounds. The coating composition is applied to a substrate and cured into a film by heating to form a coating composition. The coating composition undergoes a post-treatment step of heating and humidifying, whereby hydroxyl groups are regenerated on the hydroxyl-containing hydrocarbon groups, forming a moisture-absorbing film with excellent moisture absorption properties.

[0058] The coating composition may usually contain a solvent. From the viewpoint of coatability, the boiling point of the solvent is preferably 60 to 160°C, more preferably 70 to 90°C. The type of solvent is not particularly limited as long as it does not affect the storage of the polysiloxane, and examples include polar organic solvents such as ethanol, methanol, and IPA, as well as water. From the viewpoint of solubility, the solvent preferably contains at least one polar organic solvent or water.

[0059] The content of the solvent in the coating composition is not particularly limited, and is usually an amount such that the content of the silane compound (I) (including disiloxane (I')) relative to the total amount of the coating composition is 5 to 80 mass %, preferably 10 to 50 mass %.

[0060] The coating composition may contain one or more additives selected from the group consisting of antioxidants, UV absorbers, IR absorbers, leveling agents, inorganic particles, organic particles, and polymerization initiators.

[0061] [Moisture-absorbing film] The thickness of the hygroscopic film is usually 1 μm or more, preferably 10 μm or more, and more preferably 100 μm or more. There is no particular upper limit to the thickness of the hygroscopic film, and the thickness of the hygroscopic film may be, for example, 1000 μm or less.

[0062] [Method of manufacturing laminate] The method for producing a laminate of the present disclosure includes a coating film formation step of applying a coating composition containing the silane compound (I) and / or a derivative thereof to a substrate, and then curing the coating composition by heating to form a coating film composition, and a post-treatment step of subjecting the coating film composition to a heating and humidifying treatment.

[0063] Specifically, as shown in Fig. 1, first, in the coating material preparation step S1, a coating material composition containing a silane compound is prepared. In the coating material preparation step S1, the silane compound (I) (containing disiloxane (I')) and a solvent are usually mixed. This preparation step may usually be carried out at room temperature (e.g., 15 to 25°C).

[0064] Next, in the coating film formation step S2, the coating composition is first applied to a substrate. The application method is not particularly limited as long as the coating composition can be attached or applied to at least a portion of the substrate surface, and examples include flow coating, drop casting, spin coating, bar coating, spray coating, curtain coating, dip coating, and die coating. The substrate to which the coating composition has been applied is then dried (e.g., calcined) and then cured by heating (e.g., baking). The curing is a curing reaction based on a siloxane bond-forming reaction (i.e., a dehydration condensation reaction).

[0065] The heating temperature and heating time are not particularly limited as long as curing is achieved. For example, the heating temperature may be 120°C or higher, particularly 120 to 250°C. The heating time is appropriately set depending on the heating temperature. For example, when the heating temperature is 150 to 200°C, the heating time may be 0.5 to 5 hours, particularly 1 to 3 hours.

[0066] After forming the coating composition by heating, a post-treatment step S3 in which a heating and humidifying treatment is carried out is carried out, whereby the hydroxyl groups lost as a side reaction of the dehydration condensation reaction in the coating formation step are regenerated, making it possible to obtain a laminate with excellent moisture absorption and scratch resistance.

[0067] The heating and humidifying conditions in the post-treatment step S3 are a temperature of 40° C. or higher, a humidity of 95% RH or higher, and a treatment time of 1 hour or longer, preferably a temperature of 80° C. or higher, a humidity of 95% RH or higher, and a treatment time of 1 hour or longer.

[0068] Even at a relatively low temperature range of 40°C to 50°C, hydroxyl groups can be regenerated, and a laminate with practically acceptable moisture absorption and scratch resistance can be obtained with a treatment time of 1 hour or more. However, when post-treatment is performed at such a relatively low temperature range, it is preferable to set the treatment time to longer than 1 hour. For example, when the post-treatment step S3 is performed under conditions of a temperature of 40°C, a humidity of 95% RH, and a treatment time of 16 hours, the resulting laminate has excellent moisture absorption and scratch resistance.

[0069] The heating and humidification treatment can be carried out using a thermo-humidistat chamber that can maintain a predetermined temperature and humidity, but it is not limited to the method using a thermo-humidistat chamber; it can also be carried out by immersing the material in water set to a predetermined temperature.

[0070] FIG. 2 shows an outline of the reaction of the hydroxyl group-containing hydrocarbon group when a laminate is produced by the production method of the present disclosure using alkylene glycol silane (trade name "X-12-1098" manufactured by Shin-Etsu Chemical Co., Ltd.) as the silane compound (I).

[0071] As shown in Figure 2, the coating film formation step S2 forms siloxane bonds from the silane compound (I), producing a coating film composition containing a polysiloxane. At this time, it is believed that some of the hydroxyl groups in the hydroxyl-containing hydrocarbon groups of the polysiloxane in the coating film composition have been consumed by a side reaction that occurs during the siloxane bond formation process, i.e., a reaction in which an Si-OH bond and a C-OH bond form an Si-O-C bond. By subjecting the coating film composition in this state to the post-treatment step S3, the Si-O-C bonds formed in the side reaction are cleaved, and hydroxyl groups are regenerated in the hydroxyl-containing hydrocarbon groups. The manufacturing method of the present disclosure uses this reaction pathway to produce a laminate that is rich in hydroxyl groups and has excellent moisture absorption and scratch resistance.

[0072] <Examples and Comparative Examples> In Examples 1 to 8 and Comparative Example 1, alkylene glycol silane was used as the silane compound (I), and laminates were produced under the conditions shown in Table 2, and their moisture absorption and hardness were evaluated. Furthermore, in Comparative Example 2, a glass substrate itself was used as the substrate. The alkylene glycol silane used was trade name "X-12-1098" (manufactured by Shin-Etsu Chemical Co., Ltd.). This alkylene glycol silane is a compound belonging to silane derivatives having a hydrophilic group-containing hydrocarbon group, and is a disiloxane compound represented by the structural formula (I') above.

[0073] [Table 2]

[0074] [Example 1] The laminate was produced by the following procedure: First, in the coating material preparation step S1, X-12-1098 (1.1 g) and ethanol (3.2 g) were added to obtain a coating material composition.

[0075] Next, in the coating film formation step S2, the coating composition was applied to a glass substrate (thickness 2 mm) degreased with IPA (isopropyl alcohol) using a bar coater (120 μm) so that the thickness after baking would be approximately 10 μm. The glass substrate with the coating composition applied was pre-baked (60°C x 2 hours) and then baked (180°C x 2 hours) to form a coating film composition (thickness 10 μm).

[0076] In the post-treatment step S3, the coating composition obtained in the coating film forming step S2 was heated and humidified at 80°C and 95% RH for 1 hour to obtain a laminate.

[0077] [Examples 2 to 8, Comparative Example 1] As shown in Table 1, the procedure is substantially the same as in Example 1 except that the conditions for the heating and humidifying treatment in the post-treatment step are different, and therefore a description thereof will be omitted.

[0078] <Evaluation test> [Anti-fogging] The anti-fogging properties of each laminate were measured by the following method.

[0079] The laminate was placed on a cool plate (SA-800) cooled to 10°C in an environment of 23°C and 50% RH, and the time until fogging was observed was measured. The longer the time until fogging was observed, the higher the anti-fogging property, that is, the higher the moisture absorption of the moisture-absorbing film.

[0080] The moisture absorption was evaluated based on the measured anti-fogging duration: ◎: 100 seconds or less anti-fogging duration (best) ○: 50 seconds ≦ Anti-fogging duration < 100 seconds (good) △: 30 seconds or more, anti-fogging duration < 50 seconds (no practical problems) ×: Anti-fogging duration <30 seconds (problems in practical use) In Examples 1 to 8, in which a heating and humidifying treatment was carried out in the post-treatment step, the anti-fogging effect lasted longer and the moisture absorption was higher than in Comparative Example 1, in which no post-treatment was carried out.

[0081] [Pencil hardness] The pencil hardness of the moisture-absorbing film in each laminate was determined in accordance with JIS K5600, and the moisture absorption was evaluated based on the measured anti-fogging duration: ◎: 2H or less pencil hardness (best) ○: H = pencil hardness (good) △: Pencil hardness > H (no practical problems) Examples 1 to 8, which underwent heating and humidifying treatment in the post-treatment step, had hardness that was practically acceptable.

[0082] [comprehensive evaluation] The evaluation results for moisture absorption and scratch resistance were evaluated comprehensively as follows: ⊚: The evaluation results of anti-fogging property and pencil hardness were ⊚. ◯: The lowest evaluation result of the antifogging property and pencil hardness was ◯. △: The lowest evaluation result of the anti-fogging property and pencil hardness was △. ×: The worst evaluation result was × in the evaluation results of antifogging property and pencil hardness.

[0083] [Confirmation of hydroxyl groups by FTIR] The coating composition was prepared in the same manner as in Example 1, and FTIR spectra were measured for three samples: immediately after baking, after treatment at 80°C and 95% RH for 7 hours, and after treatment at 80°C and 95% RH for 24 hours. This confirmed that the hydroxyl groups had been regenerated by the post-treatment process. FTIR measurements were performed using a Perkin Elmer Spectrum 100. As shown in Figure 3, the peak of the hydroxyl groups on silicon (approximately 870 cm) that was slightly observed immediately after baking was -1 ~Approx. 950cm -1 ) increased with the passage of treatment time, confirming that the hydroxyl groups were regenerated by the heating and humidifying treatment. [Industrial Applicability]

[0084] The laminates and methods for producing them of the present disclosure are useful in any application where moisture absorption properties (such as anti-fogging properties and moisture conditioning properties) are required. [Explanation of symbols]

[0085] S1 Coating Preparation Engineering S2 Coating Formation Engineering S3 Post-processing Engineering

Claims

1. A method for producing a laminate having a substrate and a moisture-absorbing film formed on a portion of at least one surface of the substrate, comprising: The following general formula (I): R １ ａ R ２ ｂ Si(OR １０１ ) （４－ａ－ｂ） …(I) [In formula (I), R １ is a hydroxyl group-containing hydrocarbon group whose δH relating to the Hansen solubility parameter satisfies the relational expression δH≧13, R ２ is a monovalent hydrocarbon group, R １０１ is a hydrogen atom or a monovalent hydrocarbon group, a is an integer of 1 or 2; b is an integer from 0 to 2; the sum of a and b is an integer of 3 or less.], and then applying a coating composition containing the silane compound (I) and / or a derivative thereof to the substrate, and then curing the coating composition by heating to form a coating composition; and a post-treatment step of subjecting the coating composition to a heating and humidifying treatment at a temperature of 40°C or higher and 80°C or lower and a humidity of 95% RH or higher for 1 hour to 16 hours, thereby adding hydroxyl groups to the coating composition.

2. In the formula (I), R １ is represented by the following general formula (i): 【Chemistry 1】 [In formula (i), n is an integer of 1 to 10, wherein * represents a carbon atom which may have a bond, and when one carbon atom having * is present in one molecule, that carbon atom is directly bonded to a silicon atom of the silane compound (I). When two or more carbon atoms having * are present in one molecule, any one of the carbon atoms is directly bonded to a silicon atom of the silane compound (I). The method for producing a laminate according to claim 1, wherein the silane compound (I) is a hydroxyl group-containing hydrocarbon group having an organic chain represented by the following formula:

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