Sumitomo Chemical Company, Limited

Shoichi Ozawa

Nobuyuki Hatanaka

Tatsuaki Kasai

Daichi Fujimoto

Yosuke Ota

Shinnosuke Yoshioka

Disclosed is a retardation film which shows a high light selective absorbency to visible rays having short wavelengths near 400 nm to have a high light resistance, and which can give, when used in a display device, good display properties to the display device. This film is a retardation film, satisfying all of the following formulae (1) to (4): 2&#x2264;A(380) (1), 0.5&#x2264;A(400) (2), 0.4&#x2265;A(420)/A(400) (3), and 100 nm&#x2264;Re(550)&#x2264;170 nm (4), in which each A(&#x3bb;) represents the absorbance of the film at a wavelength &#x3bb; nm, and Re (550) represents the in-plane retardation value of the film to a light ray having a wavelength of 550 nm.

Retardation film

Provided is an optical laminate which has high absorption selectivity to short-wavelength visible light having wavelengths around 400 nm and hence high light fastness and can impart better display characteristics when used for a display device. The optical laminate comprises at least one polarizing plate and at least one pressure-sensitive adhesive layer and satisfying the following formulae (1) and (2):(400)&#x2265;0.5&#x2003;&#x2003;(1)(420)/(400)&#x2264;0.3&#x2003;&#x2003;(2)

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Niihama, Japan

Shoichi Ozawa