Abstract: A process for preparing a membrane comprising applying a composition comprising a polyimide to a gas-permeable support and irradiating the composition with UV-C light source to form a discriminating layer on the support, wherein: (i) the UV-C light source emits light having a wavelength in the range 200 to 280 nm; (ii) the irradiation is performed for a period of time in the range 0.

Abstract: A composite membrane comprising: a) a porous support; b) a gutter layer; and c) a discriminating layer which satisfies Formula (1): wherein: Ø is <4; x is the arithmetic mean of N measurements of the thickness of the discriminating layer and has a value of between 30 and 150 nm; N is at least 100; xlow_meas is the thickness in nm of an individual measurement of thickness within the N measurements; x>xlow_meas>0; and n is the number of individual thickness measurements where x>xrow_meas, >0 ? = x _ ( N - n ) ? ( n - ? i = 1 n ? ? ( 1 - 1 x low meas ) ) Formula ? ? ( 1 )

Abstract: A process for preparing a composite membrane comprising the steps of: a) applying a radiation-curable composition to a porous support; b) irradiating the composition and thereby forming a layer of cured polymer of thickness 20 to 400 nm on the support; c) forming a discriminating layer on the layer of cured polymer; and d) optionally forming a protective layer on the discriminating layer; wherein the radiation-curable composition comprises a partially crosslinked, radiation-curable polymer comprises dialkylsiloxane groups. Composite membranes are also claimed.

Abstract: A composite membrane comprising: a) a porous support; b) a gutter layer; and c) a discriminating layer which satisfies Formula (1): wherein: Ø is <4; x is the arithmetic mean of N measurements of the thickness of the discriminating layer and has a value of between 30 and 150 nm; N is at least 100; xlow_meas is the thickness in nm of an individual measurement of thickness within the N measurements; x>xlow_meas>0; and n is the number of individual thickness measurements where x>xrow_meas, >0 ? = x _ ( N - n ) ? ( n - ? i = 1 n ? ? ( 1 - 1 x low meas ) ) Formula ? ? ( 1 )

Abstract: A process for preparing a composite membrane comprising the steps of: a) applying a radiation-curable composition to a porous support; b) irradiating the composition and thereby forming a layer of cured polymer of thickness 20 to 400 nm on the support; c) forming a discriminating layer on the layer of cured polymer; and d) optionally forming a protective layer on the discriminating layer; wherein the radiation-curable composition comprises a partially crosslinked, radiation-curable polymer comprises dialkylsiloxane groups. Composite membranes are also claimed.

Abstract: The present invention relates to a method of changing an identification code of a transaction authorisation medium, wherein the transaction authorisation medium is designed for authorising transactions of a credit parameter. The identification code is registered by the transaction authorisation medium and by a management server. The transaction authorisation medium is operatively connected to a terminal for changing the identification code, and the terminal is operatively and communicatively connected to the management server via a public telecommunication network. The method comprises the steps of: initiating a transaction; storing the changed identification code in the transaction authorisation medium; and transmitting a changed identification code in encrypted form to the management server via the telecommunication network for carrying out the transaction.