INORGANIC GLASS COATING AGENT

Abstract

An inorganic glass coating agent is composed mainly of an alkoxysilane and silane coupling agent, wherein the alkoxysilane is a trifunctional alkoxysilane, with a flash point of no higher than 40° C. as equivalent to a class I petroleum and/or a class II petroleum, and a molecular weight of 180 or lower, and wherein at least one of the alkoxysilanes is present at 10 wt % to 80 wt %, where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt %. The inorganic glass coating agent exhibits stable drying and hardening properties not only under ordinary conditions but also under poor conditions by selecting an alkoxysilane having a relatively low molecular weight and low flash point, with high reactivity.

Claims

1. A coating agent composed mainly of alkoxysilanes and a silane coupling agent, wherein at least one of the alkoxysilanes is a trifunctional alkoxysilane with a flash point of no higher than 40° C. and a molecular weight of 180 or less, and wherein at least one of the alkoxysilanes accounts for 10 wt % to 80 wt % of the coating agent.

2. The coating agent according to claim 1, wherein the silane coupling agent comprises at least one epoxy silane coupling agent at a content of 10 wt % to 80 wt % of the coating agent, where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt % of the coating agent.

3. The coating agent according to claim 1, wherein the alkoxysilanes and the silane coupling agent, composed mainly of the trifunctional alkoxysilane and an epoxy silane coupling agent, are mixed with aqueous and/or solvent-based colloidal silica, water and/or a diluting solvent, and a catalyst.

Description

DESCRIPTION OF EMBODIMENTS

[0038] An embodiment of the invention will now be described in detail. For development of the inorganic glass coating agent of the invention comprising an alkoxysilane and a silane coupling agent, colloidal silica and a catalyst such as phosphoric acid, selection of the alkoxysilane and silane coupling agent is important. First, a trifunctional alkoxysilane must have a relatively low molecular weight, low flash point and high reactivity, as properties required for an alkoxysilane. Specific trifunctional alkoxysilanes that may be used include methyltrimethoxysilane, methyltriethoxysilane and n-propyltrimethoxysilane.

[0039] Table 4 shows Mixing Examples with parameters of flash point, hazardous material classification, molecular weight and content of major trifunctional alkoxysilanes, where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt %.

TABLE-US-00004 TABLE 4 Flash Hazardous Sample Alkoxysilane (wt %) point material Molecular No. Type Content (° C.) classification weight  1 Alkoxysilane 10 8 Class I petroleum 136  2 A 30  3 50  4 80  5* 90  6* Alkoxysilane 5 36 Class II petroleum 164  7 B 10  8 40  9 70 10* 85 11 Alkoxysilane 10 40 Class II petroleum 178 12 C 30 13 60 14 80 15* 90 16* Alkoxysilane 10 23 Class II petroleum 218 17* D 30 18* 60 19* 80 20* 95 21* Alkoxysilane 15 57 Class II petroleum 206 22* E 35 23* 60 24* 80 25* 95 A “*” symbol indicates that the sample falls outside of the range of the invention.

[0040] For each of the samples in Table 4, a coating agent was prepared according to conventional material specifications, comprising silane in an amount of 40 wt %, colloidal silica in an amount of 59 wt % (about 12% by solid weight) and phosphoric acid in an amount of 1 wt % based on a total coating agent content of 100 wt o, and coated onto a glass sheet under low temperature conditions (room temperature: 10° C., humidity: 50%) and high-humidity conditions (room temperature: 25° C., humidity: 80%), as poor conditions, and coated under ordinary conditions (room temperature: 25° C., humidity: 50%) onto a concrete floor having a strong suction property, and the drying time and next-day hardness value of each was measured, using parameters of differences in alkoxysilane flash point and molecular weight and contents, with the results shown in Table 5.

TABLE-US-00005 TABLE 5 Low temperature High humidity Concrete floor Sample Alkoxysilane Touch-drying Next-day Touch-drying Next-day Touch-drying Next-day No. type time (min) hardness time (min) hardness time (min) hardness Assessment 1 Alkoxysilane 45 3H 50 3H 40 3H ∘ 2 A 40 3H 45 3H 35 3H ∘ 3 30 4H 35 4H 30 3H ∘ 4 25 4H 30 4H 25 3H ∘  5* 20 1H 25 2H 25 1H x  6* Alkoxysilane 55 2H 65 2H 65 2H x 7 B 50 3H 55 3H 55 3H ∘ 8 40 3H 50 4H 50 3H ∘ 9 25 4H 45 3H 45 3H ∘ 10* 30 1H 35 2H 40 2H x 11  Alkoxysilane 55 3H 55 3H 60 3H ∘ 12  C 50 3H 50 3H 55 3H ∘ 13  45 4H 45 3H 50 3H ∘ 14  30 4H 40 4H 45 3H ∘ 15* 25 2H 35 2H 40 2H x 16* Alkoxysilane 75 1H 75 1H 70 1H x 17* D 65 2H 70 2H 65 2H x 18* 60 3H 65 2H 60 2H x 19* 50 2H 55 2H 50 2H x 20* 45 F 50 F 50 1H x 21* Alkoxysilane 90 1H 90 1H 80 1H x 22* E 75 2H 80 1H 70 1H x 23* 70 2H 80 2H 65 2H x 24* 65 2H 65 2H 60 2H x 25* 50 2H 60 1H 55 1H x A “*” symbol indicates that the sample falls outside of the range of the invention. Assessments: ∘, Δ, x; ∘ : All had touch-drying times of within 60 minutes and next-day hardnesses of 3H or greater. x: One or more had a touch-drying time of 60 minutes or longer and a next-day hardness of below 3H.

[0041] As shown by the results in Table 5, a trifunctional alkoxysilane having a lower flash point and a lower molecular weight of the alkoxysilane exhibits a more satisfactory drying property and higher next-day hardness. Specifically, if the proportion with a flash point of no higher than 40° C. equivalent to a class I petroleum or class II petroleum and a molecular weight of 180 or lower is 10 wt % to 80 wt %, where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt %, then even a concrete floor will dry within 60 minutes, with a next-day hardness of 3H or greater, at a room temperature of 10° C. and humidity of 80%. By thus selecting and adding such an alkoxysilane it is possible to obtain stable drying and hardening properties even under low temperature, high-humidity conditions, and with suction-type flooring materials such as concrete.

[0042] It was confirmed, however, that the drying and hardening properties during construction and the next-day hardness were both improved as a result of the excellent drying and hardening properties of the alkoxysilane, although it is important to exhibit compatibility with the alkoxysilane and the aqueous and solvent-based colloidal silica, as well as exhibiting properties as a floor coating agent, as mentioned above. Specifically, it is necessary to provide effects of inhibiting whitening and cracking caused by rapid hardening shrinkage, improving brittleness and imparting flexibility, while also improving the properties required for a coating film such as recoatability, static electrical characteristics, solution resistance and slidability. Selection of the silane coupling agent was therefore considered. Specific silane coupling agents that were examined included epoxy group silane coupling agents [2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane and 3-glycidoxypropyltriethoxysilane], an acrylic group silane coupling agent [3-acryloxypropyltrimethoxysilane], vinyl group silane coupling agents [vinyltrimethoxysilane and vinyltriethoxysilane], amino group silane coupling agents [N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane], and methacryl group silane coupling agents [3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane and 3-methacryloxypropyltriethoxysilane].

[0043] A particularly satisfactory alkoxysilane A was selected from among Tables 4 and 5, and Mixing Examples with different types and mixing amounts of different silane coupling agents as parameters were prepared as shown in Table 6. The total amounts of alkoxysilane A and each silane coupling agent were 90 to 95 wt %, with the remaining 5 to 10 wt % consisting of other alkoxysilanes or silane coupling agents and various additives.

TABLE-US-00006 TABLE 6 Sample Silane coupling agents (wt %) Alkoxysilane No. Type Content A (wt % ) 26 Epoxy group silane 10 80 27 coupling agent A 20 70 28 40 50 29 60 30 30 80 10 31* 90 0 32* Acrylic group silane 10 80 33* coupling agent B 20 70 34* 50 40 35* 75 15 36* 95 0 37* Vinyl group silane 10 80 38* coupling agent C 20 70 39* 50 40 40* 75 15 41* 90 0 42* Amino group silane 10 80 43* coupling agent D 20 70 44* 50 40 45* 75 15 46* 95 0 47* Methacryl group silane 10 80 48* coupling agent E 30 60 49* 60 30 50* 80 10 51* 95 0 A “*” symbol indicates that the sample falls outside of the range of the invention.

[0044] For each of the samples listed in Table 6, a coating agent was prepared according to conventional material specifications, comprising silane in an amount of 40 wt %, colloidal silica in an amount of 59 wt % (about 12% by solid weight) and phosphoric acid in an amount of 1 wt % based on a total coating agent content of 100 wt %, and coated under low temperature conditions (room temperature: 10° C., humidity: 50%) and high-humidity conditions (room temperature: 25° C., humidity: 80%), as poor conditions, and the properties were evaluated about 24 hours after coating. The results are shown in Tables 7-1 to 7-4.

TABLE-US-00007 TABLE 7-1 Low-temperature conditions Mar Static proofness electrical Next- Silane coupling test character- day Coefficient of Sample agents (wt %) Whitening/ (toughness istic X hard- Solution resistance slip resistance Assess- No. Type Content Finish cracking test) (10.sup.XΩ) ness Water Alcohol Acid Alkali Dry Wet ment 26  Epoxy 10 Good None −9 9.9 3H ∘ ∘ ∘ Δ 0.72 0.60 ∘ 27  group 20 Good None −8 9.7 4H ∘ ∘ ∘ Δ 0.75 0.61 ∘ 28  silane 40 Good None −5 9.5 5H ∘ ∘ ∘ ∘ 0.77 0.62 ∘ 29  coupling 60 Good None −4 9.2 4H ∘ ∘ ∘ Δ 0.78 0.63 ∘ 30  agent A 80 Good None −5 9.2 3H ∘ ∘ ∘ Δ 0.80 0.64 ∘ 31* 90 Good None −15 9.1 2H ∘ x x x 0.81 0.64 x 32* Acrylic 10 Weak Whitening −33 12.0 1H Δ x x x 0.75 0.45 x group gloss 33* silane 20 Uneven None −25 11.5 2H ∘ Δ ∘ x 0.79 0.50 x coupling gloss 34* agent B 50 Uneven None −16 11.0 2H ∘ ∘ ∘ Δ 0.83 0.55 x gloss 35* 75 Uneven None −13 10.7 1H Δ x x x 0.85 0.60 x gloss 36* 95 Uneven None −20 10.3 F Δ x x x 0.88 0.63 x gloss 37* Vinyl 10 Weak Whitening −38 12.5 1H Δ x x x 0.74 0.60 x group gloss 38* silane 20 Weak None −35 12.0 2H ∘ Δ ∘ Δ 0.77 0.62 x coupling gloss 39* agent C 50 Weak None −30 11.7 1H ∘ Δ ∘ Δ 0.80 0.63 x gloss 40* 75 Weak None −24 11.5 1H Δ x x x 0.83 0.65 x gloss 41* 90 Weak None −35 11.3 F Δ x x x 0.90 0.66 x gloss A “*” symbol indicates that the sample falls outside of the range of the invention.

TABLE-US-00008 TABLE 7-2 Low-temperature conditions Mar Static proofness electrical Next- Silane coupling test character- day Coefficient of Sample agents (wt %) Whitening/ (toughness istic X hard- Solution resistance slip resistance Assess- No. Type Content Finish cracking test) (10.sup.XΩ) ness Water Alcohol Acid Alkali Dry Wet ment 42* Amino 10 Coating — — — — — — — — — — x group gelled 43* silane 20 Coating — — — — — — — — — — x coupling gelled 44* agent D 50 Coating — — — — — — — — — — x gelled 45* 75 Coating — — — — — — — — — — x gelled 46* 95 Coating — — — — — — — — — — x gelled 47* Methacryl 10 Weak Whitening −35 11.0 1H Δ x x x 0.77 0.50 x group gloss 48* silane 30 Uneven None −15 10.7 2H ∘ Δ ∘ Δ 0.80 0.54 x coupling gloss 49* agent E 60 Uneven None −10 10.3 2H ∘ ∘ ∘ Δ 0.85 0.58 x gloss 50* 80 Uneven None −20 10.1 F ∘ ∘ ∘ Δ 0.90 0.60 x gloss 51* 95 Uneven None −30 9.9 F Δ x x x 0.92 0.64 x gloss A “*” symbol indicates that the sample falls outside of the range of the invention.

TABLE-US-00009 TABLE 7-3 High-humidity conditions Mar Static proofness electrical Next- Silane coupling test character- day Coefficient of Sample agents (wt %) Whitening/ (toughness istic X hard- Soution resistance slip resistance Assess- No. Type Content Finish cracking test) (10.sup.XΩ) ness Water Alcohol Acid Alkali Dry Wet ment 26  Epoxy 10 Good None −10 9.9 3H ∘ ∘ ∘ Δ 0.72 0.61 ∘ 27  group 20 Good None −8 9.8 4H ∘ ∘ ∘ Δ 0.75 0.62 ∘ 28  silane 40 Good None −7 9.6 4H ∘ ∘ ∘ ∘ 0.77 0.62 ∘ 29  coupling 60 Good None −5 9.2 4H ∘ ∘ ∘ Δ 0.78 0.64 ∘ 30  agent A 80 Good None −5 9.1 3H ∘ ∘ ∘ Δ 0.80 0.64 ∘ 31* 90 Good None −18 9.0 2H ∘ x x x 0.81 0.66 x 32* Acrylic 10 Weak Whitening −32 11.8 1H Δ x x x 0.75 0.45 x group gloss 33* silane 20 Uneven None −22 11.6 1H ∘ Δ ∘ x 0.80 0.51 x coupling gloss 34* agent B 50 Uneven None −15 11.2 2H ∘ ∘ ∘ Δ 0.83 0.56 x gloss 35* 75 Uneven None −12 10.8 1H Δ x x x 0.84 0.60 x gloss 36* 95 Uneven None −20 10.5 F Δ x x x 0.88 0.62 x gloss 37* Vinyl 10 Weak Whitening −35 12.2 1H Δ x x x 0.73 0.61 x group gloss 38* silane 20 Weak None −33 12.0 2H ∘ Δ ∘ Δ 0.76 0.60 x coupling gloss 39* agent C 50 Weak None −20 11.8 1H ∘ Δ ∘ Δ 0.78 0.62 x gloss 40* 75 Weak None −22 11.6 F Δ x x x 0.83 0.65 x gloss 41* 90 Weak None −33 11.2 F Δ x x x 0.88 0.67 x gloss A “*” symbol indicates that the sample falls outside of the range of the invention.

TABLE-US-00010 TABLE 7-4 High-humidity conditions Mar Static proofness electrical Next- Silane coupling test character- day Coefficient of Sample agents (wt %) Whitening/ (toughness istic X hard- Soution resistance slip resistance Assess- No. Type Content Finish cracking test) (10.sup.XΩ) ess Water Alcohol Acid Alkali Dry Wet ment 42* Amino 10 Coating — — — — — — — — — — x group gelled 43* silane 20 Coating — — — — — — — — — — x coupling gelled 44* agent D 50 Coating — — — — — — — — — — x gelled 45* 75 Coating — — — — — — — — — — x gelled 46* 95 Coating — — — — — — — — — — x gelled 47* Methacryl 10 Weak Whitening −26 11.2 1H Δ x x x 0.78 0.51 x group gloss 48* silane 30 Uneven None −13 10.8 2H ∘ Δ ∘ Δ 0.81 0.53 x coupling gloss 49* agent E 60 Uneven None −10 10.5 1H ∘ ∘ ∘ Δ 0.87 0.59 x gloss 50* 80 Uneven None −15 10.3 1H ∘ ∘ ∘ Δ 0.92 0.60 x gloss 51* 95 Uneven None −25 10.0 F Δ x x x 0.93 0.63 x gloss A “*” symbol indicates that the sample falls outside of the range of the invention.

[0045] The finish and the presence or absence of whitening and cracking were determined by visual observation of the outer appearance after applying the coating agent to vinyl chloride flooring tiles and confirming dryness to the touch.

[0046] A mar proofness test was carried out instead of the toughness evaluation test. The mar proofness test was carried out by a scratch test with 10 back and forth passes using a wire brush with an approximately 750 g weight, judging the state of gloss deterioration (gloss value after marring-gloss value before marring). A score of 10 points or less was judged as satisfactory gloss deterioration.

[0047] The static electrical characteristic (surface resistivity) was determined using a surface resistivity tester (YC-103), with 5 measurements each and recording the average value (X represents the 10-based index, and therefore the surface resistivity is 10.sup.XΩ). The obtained static electrical characteristic (surface resistivity) was judged to be satisfactory at ≤1×10.sup.10 Ω, as a level where static electricity is no longer sensed based on empirical data.

[0048] The pencil hardness was based on JIS K5600. A sample prepared by coating onto a glass sheet or metal fragment was anchored on a horizontal stage with the coated surface facing upward, and a pencil was held at an angle of about 45° and used to scratch the coated surface while pressing it as firmly as possible against the coated surface without breaking the lead core, along a length of about 1 cm at a uniform speed in the forward direction from the tester. The hardest pencil that did not cause breakage of the coated surface was recorded as the hardness number. A pencil hardness of 3H about 24 hours after construction has been empirically shown to be able to withstand damage due to abrasion by walking.

[0049] The solution resistance values were confirmed by the method of JIS K5600, for water resistance (deionized water, liquid resistance; drip infusion method), alcohol resistance (70% ethanol, liquid resistance; drip infusion method), acid resistance (10% hydrochloric acid, liquid resistance; drip infusion method) and alkali resistance (saturated sodium hydroxide solution, liquid resistance; absorption medium method). An absorber disc exposed to test solution by dropping or soaking was set on the test piece and allowed to stand for 1 hour, after which it was removed and thoroughly washed. Blistering and coating film damage were immediately observed, and the evaluation assignment was “o” if the condition was unchanged from before evaluation, “Δ” if the condition changed but was restored to the original condition during a recovery period of 24 hours, or “×” if the condition changed to blistering, peeling or the like without restoration to the original condition during the recovery period. The overall judgment is satisfactory if 3 or more are evaluated as “o ”, 1 or fewer as “Δ” and none as “×”.

[0050] The slidability test was conducted according to the Resilient Polymer Floor Coverings Test Method of JIS A1454. A vinyl chloride flooring tile is coated with the coating agent to produce a sample, and a portable pull slip meter (ONO.Math.PPSM) is used to measure the tensile force (P) when pulling a sliding piece (rubber sheet with hardness: A80, thickness: 5 mm) over the test piece in a clean and dry state and in a wet state, recording the maximum tensile force (Pmax) to be the maximum value generated when the sliding piece begins to slide, and calculating the coefficient of slip resistance (C.S.R). Satisfactory evaluation is 0.7 to 0.8 in a dry state and 0.6 to 0.8 in a wet state.

Coefficient of slip resistance (C.S.R)=Maximum tensile force (Pmax)/vertical force: 785 N (W)

[0051] The assessments of “o” in Table 7-1 to Table 7-4 indicate “satisfactory finish, crack resistance, toughness (mar proofness), static electrical characteristic, pencil hardness, solution resistance and slidability”, and the assessments of “×” indicate “problem with anyone of finish, crack resistance, toughness (mar proofness), static electrical characteristic, pencil hardness, solution resistance or slidability”.

[0052] As mentioned above, in the test results with different silane coupling agents as parameters, only the epoxy group silane coupling agents exhibited satisfactory results for all evaluations including finish, presence or absence of whitening or cracking, mar proofness testing, static electrical characteristic, next-day hardness, various solution resistance testing and slide properties under dry and wet conditions. Although coating films formed with the vinyl group silane coupling agents, the acrylic group silane coupling agent and the methacryl group silane coupling agents, the evaluations for mar proofness testing, static electrical characteristic, hardness and solution resistance testing were all inferior compared to the epoxy group silane coupling agents. The amino group silane coupling agents formed an unsuitable gel due to the use of phosphoric acid as the catalyst. The most favorable results were therefore obtained with epoxy group silane coupling agents, the most satisfactory results being obtained with contents of 10 wt % to 80 wt %.

[0053] The results described above demonstrate that the inorganic glass coating agent is preferably one wherein the alkoxysilane is a trifunctional alkoxysilane, with a flash point of no higher than 40° C. as equivalent to a class I petroleum and/or a class II petroleum and a molecular weight of 180 or lower, and wherein the content of the alkoxysilane is 10 wt % to 80 wt %, where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt %. Furthermore, the silane coupling agent preferably comprises at least one epoxy group silane coupling agent, at a content of 10 wt % to 80 wt % where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt %. Testing was therefore repeated using these combinations.

[0054] Combinations of alkoxysilane and silane coupling agents were used for repeat testing. Table 8 shows Mixing Examples with the contents of alkoxysilanes A, B and C which were satisfactory in Table 5 as parameters, with epoxy group silane coupling agents as silane coupling agents, and with the total contents including the alkoxysilanes set to 90 wt %. The remaining 10 wt % consisted of other alkoxysilanes, silane coupling agents and various additives.

TABLE-US-00011 TABLE 8 Epoxy group silane coupling Sample Alkoxysilane (wt %) agent content No. Type Content (wt %) 52 Alkoxysilane A 10 80 53 (Flash point 8° C., 30 60 54 Molecular weight 136) 50 40 55 80 10 56* 90 0 57* Alkoxysilane B 5 85 58 (Flash point 36° C., 10 80 59 Molecular weight 164) 40 50 60 70 20 61* 85 5 62 Alkoxysilane C 10 80 63 (Flash point 30 60 64 40° C., Molecular 60 30 65 weight 178) 80 10 66* 90 0 A “*” symbol indicates that the sample falls outside of the range of the invention.

[0055] For each of the samples listed in Table 8, a coating agent was prepared according to conventional material specifications, comprising silane in an amount of 40 wt %, colloidal silica in an amount of 59 wt % (about 12% by solid weight) and phosphoric acid in an amount of 1 wt % based on a total coating agent content of 100 wt %, and coated under low temperature conditions (room temperature: 10° C., humidity: 50%) and high-humidity conditions (room temperature: 25° C., humidity: 60%), as poor conditions, and the properties were evaluated about 24 hours after coating. The results are shown in Tables 9-1 and 9-2.

TABLE-US-00012 TABLE 9-1 Low-temperature conditions (room temperature: 10° C., humidity: 50%) Mar Static proofness electrical Next- Alkoxysilane test character- day Coefficient of Sample (wt %) Whitening/ (toughness istic X hard- Soution resistance slip resistance Assess- No. Type Content Finish cracking test) (10.sup.XΩ) ness Water Alcohol Acid Alkali Dry Wet ment 52 Alkoxysilane 10 Good None −9 9.2 3H ∘ ∘ ∘ Δ 0.80 0.64 ∘ 53 A (Flash 30 Good None −4 9.2 4H ∘ ∘ ∘ Δ 0.78 0.63 ∘ 54 point 8° C., 50 Good None −5 9.5 5H ∘ ∘ ∘ ∘ 0.77 0.62 ∘ 55 Molecular 80 Good None −9 9.9 3H ∘ ∘ ∘ Δ 0.72 0.60 ∘  56* weight 136) 90 Weak Whitening −20 9.9 2H ∘ x x x 0.70 0.58 x gloss  57* Alkoxysilane 5 Good None −15 9.5 2H Δ Δ Δ Δ 0.81 0.69 x 58 B (Flash 10 Good None −10 9.6 3H ∘ ∘ ∘ Δ 0.78 0.68 ∘ 59 point 36° C., 40 Good None −7 9.7 4H ∘ ∘ ∘ Δ 0.76 0.67 ∘ 60 Molecular 70 Good None −5 9.9 3H ∘ ∘ ∘ ∘ 0.74 0.65 ∘  61* weight 164) 85 Weak Whitening −18 10.3 2H Δ x x x 0.71 0.63 x gloss 62 Alkoxysilane 10 Good None −10 9.5 3H ∘ ∘ ∘ Δ 0.80 0.70 ∘ 63 C (Flash 30 Good None −8 9.6 4H ∘ ∘ ∘ Δ 0.78 0.68 ∘ 64 point 40° C., 60 Good None −6 9.8 3H ∘ ∘ ∘ Δ 0.75 0.65 ∘ 65 Molecular 80 Good None −10 9.9 3H ∘ ∘ ∘ Δ 0.74 0.62 ∘  66* weight 178) 90 Weak Whitening −18 10.2 2H Δ x x x 0.73 0.60 x gloss A “*” symbol indicates that the sample falls outside of the range of the invention.

TABLE-US-00013 TABLE 9-2 High-humidity conditions (room temperature: 25° C., humidity: 80%) Mar Static proofness electrical Next- Alkoxysilane test character- day Coefficient of Sample (wt %) Whitening/ (toughness istic X hard- Soution resistance slip resistance Assess- No. Type Content Finish cracking test) (10.sup.XΩ) ness Water Alcohol Acid Alkali Dry Wet ment 52 Alkoxysilane 10 Good None −8 9.1 3H ∘ ∘ ∘ Δ 0.80 0.64 ∘ 53 A (Flash 30 Good None −5 9.2 4H ∘ ∘ ∘ Δ 0.78 0.64 ∘ 54 point 8° C., 50 Good None −7 9.6 4H ∘ ∘ ∘ ∘ 0.77 0.62 ∘ 55 Molecular 80 Good None −10 9.9 3H ∘ ∘ ∘ Δ 0.72 0.61 ∘  56* weight 136) 90 Weak Whitening −18 10.0 2H ∘ x x x 0.71 0.60 x gloss  57* Alkoxysilane 5 Good None −13 9.6 2H Δ Δ Δ Δ 0.81 0.70 x 58 B (Flash 10 Good None −10 9.7 3H ∘ ∘ ∘ Δ 0.77 0.68 ∘ 59 point 36° C., 40 Good None −8 9.8 4H ∘ ∘ ∘ Δ 0.77 0.67 ∘ 60 Molecular 70 Good None −5 9.7 3H ∘ ∘ ∘ ∘ 0.75 0.67 ∘  61* weight 164) 85 Weak Whitening −20 10.1 2H Δ x x x 0.72 0.65 x gloss 62 Alkoxysilane 10 Good None −9 9.6 3H ∘ ∘ ∘ Δ 0.79 0.68 ∘ 63 C (Flash 30 Good None −7 9.6 4H ∘ ∘ ∘ Δ 0.78 0.66 ∘ 64 point 40° C., 60 Good None −7 9.8 3H ∘ ∘ ∘ Δ 0.77 0.64 ∘ 65 Molecular 80 Good None −10 9.8 3H ∘ ∘ ∘ Δ 0.75 0.63 ∘  66* weight 178) 90 Weak Whitening −20 10.2 2H Δ x x x 0.73 0.60 x gloss A “*” symbol indicates that the sample falls outside of the range of the invention.

[0056] The finish and the presence or absence of whitening and cracking were determined by visual observation of the outer appearance after applying the coating agent to vinyl chloride flooring tiles and confirming dryness to the touch.

[0057] A mar proofness test was carried out instead of the toughness evaluation test. The mar proofness test was carried out by a scratch test with 10 back and forth passes using a wire brush with an approximately 750 g weight, judging the state of gloss deterioration (gloss value after marring-gloss value before marring). A score of 10 points or less was judged as satisfactory gloss deterioration.

[0058] The static electrical characteristic (surface resistivity) was determined using a surface resistivity tester (YC-103), with 5 measurements each and recording the average value (X represents the 10-based index, and therefore the surface resistivity is 10.sup.XΩ). The obtained static electrical characteristic (surface resistivity) was judged to be satisfactory at ≤1×10.sup.10 Ω, as a level where static electricity is no longer sensed based on empirical data.

[0059] The pencil hardness was based on JIS K5600. A sample prepared by coating onto a glass sheet or metal fragment was anchored on a horizontal stage with the coated surface facing upward and a pencil was held at an angle of about 45° and used to scratch the coated surface while pressing it as firmly as possible against the coated surface without breaking the lead core, along a length of about 1 cm at a uniform speed in the forward direction from the tester. The hardest pencil that did not cause breakage of the coated surface was recorded as the hardness number. A pencil hardness of 3H about 24 hours after construction has been empirically shown to be able to withstand damage due to abrasion by walking.

[0060] The solution resistance values were confirmed by the method of JIS K5600, for water resistance (deionized water, liquid resistance; drip infusion method), alcohol resistance (70% ethanol, liquid resistance; drip infusion method), acid resistance (10% hydrochloric acid, liquid resistance; drip infusion method) and alkali resistance (saturated sodium hydroxide solution, liquid resistance; absorption medium method). An absorber disc exposed to test solution by dropping or soaking was set on the test piece and allowed to stand for 1 hour, after which it was removed and thoroughly washed. Blistering and coating film damage were immediately observed, and the evaluation assignment was “o” if the condition was unchanged from before evaluation, “Δ” if the condition changed but was restored to the original condition during a recovery period of 24 hours, or “×” if the condition changed to blistering, peeling or the like without restoration to the original condition during the recovery period. The overall judgment is satisfactory if 3 or more are evaluated as “o”, 1 or fewer as “Δ” and none as “×”.

[0061] The slidability test was conducted according to the Resilient Polymer Floor Coverings Test Method of JIS A1454. A vinyl chloride flooring tile is coated with the coating agent to produce a sample, and a portable pull slip meter (ONOPPSM) is used to measure the tensile force (P) when pulling a sliding piece (rubber sheet with hardness: A80, thickness: 5 mm) over the test piece in a clean and dry state and in a wet state, recording the maximum tensile force (Pmax) to be the maximum value generated when the sliding piece begins to slide, and calculating the coefficient of slip resistance (C.S.R). Satisfactory evaluation is 0.7 to 0.8 in a dry state and 0.6 to 0.8 in a wet state.

Coefficient of slip resistance (C.S.R)=Maximum tensile force (Pmax)/vertical force: 785 N (W)

[0062] The assessments of “o” in Table 9-1 and Table 9-2 indicate “satisfactory finish, crack resistance, toughness (mar proofness), static electrical characteristic, pencil hardness, solution resistance and slidability”, and the assessments of “×” indicate “problem with anyone of finish, crack resistance, toughness (mar proofness), static electrical characteristic, pencil hardness, solution resistance or slidability”.

[0063] Based on the test results shown in Table 9-1 and Table 9-2, a greater alkoxysilane content (lower epoxy group silane coupling agent content) tended to result in a weaker glossy finish and more whitening. Similarly, the mar proofness, next-day hardness, solution resistance and slidability when wet tended to have values outside of the acceptable ranges. This was attributed to excessively high hardness of the coating film which produced a brittle material. With a low alkoxysilane content (a high epoxy group silane coupling agent content), on the other hand, the hardening was inadequate, leading to a lack of next-day hardness and mar proofness, and insufficient solution resistance. It is therefore necessary to determine the optimum values.

[0064] The results described above demonstrate that the inorganic glass coating agent is preferably one wherein the alkoxysilane is a trifunctional alkoxysilane, with a flash point of no higher than 40° C. as equivalent to a class I petroleum or a class II petroleum, and a molecular weight of 180 or lower, and wherein the content of the alkoxysilane is 10 wt % to 80 wt %, where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt %. Furthermore, it was found to be preferable for the silane coupling agent to comprise at least one epoxy group silane coupling agent, at a content of 10 wt % to 80 wt % where the total percentage of the alkoxysilanes and silane coupling agent is 100 wt %.

Advantageous Effects of Invention

[0065] According to the present invention, by selecting an alkoxysilane having a relatively low molecular weight and low flash point, with high reactivity, it is possible to provide stabilized drying and hardening properties not only under ordinary conditions but also under poor conditions, and by selection and use of the appropriate content for the alkoxysilane and silane coupling agent it is possible to obtain stabilized drying and hardening properties and satisfactory next-day hardness and solution resistance even under low temperature conditions, under high-humidity conditions, and with flooring materials having strong suction properties, helping to provide the performance required for a protective film. The invention allows construction to be carried out in a stable manner in a wider variety of locations than previously, such as in cold climates or high temperature, high humidity regions such as Asia.

[0066] According to the invention as described above, according to claim 1 the drying and hardening properties of the coating agent are improved and stabilized drying and hardening properties can be obtained even with a suction-type flooring material under low temperature, high-humidity conditions, but there is still a need to reduce whitening and cracking caused by rapid hardening shrinkage, or to compensate for weakening of the coating film itself, while the performance of the coating film can be greatly improved by using one or more epoxy group silane coupling agents to compensate for the static electrical characteristics, recoat properties and wet/dry slidability.

[0067] According to this invention it is possible to provide an inorganic glass coating agent having a next-day hardness of 3H or greater, and also next-day solution resistance (water resistance, alcohol resistance, acid resistance and alkali resistance). By stably increasing the next-day hardness to 3H, it becomes possible to provide a high-hardness, inorganic glass coating agent that can stably exhibit hardness for the coating film, even up to an original final hardness of 10H.

[0068] The present invention makes it possible to obtain stable drying and hardening properties even under conditions which have been problematic in the past, such as during construction under low temperature conditions or construction under high-humidity conditions, or construction with suction-type flooring materials. The present invention thereby allows construction to be carried out at a wider variety of locations than in the past, permitting even greater use in the future in new maintenance systems that can serve as replacements for waxing.