Kuraray Co., Ltd.

Kansai Hara

Tetsuya Ashida

Disclosed is a grain-finished leather-like sheet including: a fiber base material; and a polyurethane skin film stacked, as a surface layer, directly on the fiber base material or via another polyurethane layer, wherein the polyurethane skin film contains at least one of a diketopyrrolopyrrole-based red pigment and an α-type phthalocyanine-based blue pigment, the grain-finished leather-like sheet further includes a clear polyurethane film layer coating the polyurethane skin film, and the grain-finished leather-like sheet has a grade of color difference, determined using a Grey scale for assessing staining, of 4-5 or more, when 0.03 g of oleic acid is added dropwise to a surface of the clear polyurethane film layer, and thereafter a white cotton fabric is reciprocated 100 times on the surface, using a crockmeter.

Grain-finished leather-like sheet and evaluation method for grain-finished leather-like sheet

Disclosed is a grain-finished leather-like sheet including a polyurethane skin film containing a polyether-based polyurethane, wherein the polyurethane skin film contains a quinacridone-based red pigment, and is colored in a red color having an L* value of ≤80, an a* value of ≥20, and a b* value of ≤15 in an L*a*b* color system, and the number of cycles of a flexing endurance test at which cracking occurs in a surface of the polyurethane skin film is 100000 or more, when the flexing endurance test is performed on the grain-finished leather-like sheet under an environment of 20° C. using a flexometer after the grain-finished leather-like sheet has been irradiated with carbon arc at a black panel temperature of 63° C. for 100 hours with an irradiance of 500±50 W/m, using ultraviolet carbon arc lamp light compliant with JIS B 7751.

Grained leather-like sheet

Disclosed is a grain-finished leather-like sheet including: a fiber base material; a polyurethane intermediate layer stacked on the fiber base material; and a polyurethane skin film stacked directly on the polyurethane intermediate layer or via another polyurethane layer, wherein the polyurethane skin film contains a silicone-modified polyurethane, and the grain-finished leather-like sheet has an uneven surface whose skewness (Ssk), kurtosis (Sku), and maximum height (Sz) of surface roughness in accordance with ISO 25178 respectively satisfy &#x2212;0.4&#x2264;Ssk&#x2264;&#x2212;0.2, 3&#x2264;Sku&#x2264;4, 60 &#x3bc;m&#x2264;Sz&#x2264;150 &#x3bc;m.

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Osaka, Japan

Kansai Hara