A cross-linkable, coating composition comprising: (i) one or more silanes comprising either of the following two options: - at least three hydrolysable groups or - at least two hydrolysable groups and at least one organofunctional group capable of forming chemical bonds upon curing, and where (i.a) the sum of said silanes constitutes at least 20% of the total mass of the coating composition's combined solids and silanes, (i.b) wherein said silanes comprise a polysilane having more than one silicon atoms connected by a non-hydrolysable organic structure, which is connected to the silicon atoms through a silicon-carbon bond, where said polysilane comprises at least one thiourethane or urea linkage, and (i.c) said silanes are optionally partly or completely hydrolysed and optionally partly condensed; and (ii) at least one low surface energy additive, wherein (ii.a) said low surface energy additive is a polydimethylsiloxane chemically bonded to at least one functional group, (ii.b) said functional group is configured for the polydimethylsiloxane moiety to cross-link with said coating composition, (ii.c) said polydimethylsiloxane has in the composition a concentration that upon curing results in 0.01 % to 15% of the mass of said cured coating, (ii.d) said polydimethylsiloxane moiety has more than 21 repeating [ 2 Si-O-] units. (i) one or more silanes comprising either of the following two options: - at least three hydrolysable groups or - at least two hydrolysable groups and at least one organofunctional group capable of forming chemical bonds upon curing, and where (i.a) the sum of said silanes constitutes at least 20% of the total mass of the coating composition's combined solids and silanes, (i.b) wherein said silanes comprise a polysilane having more than one silicon atoms connected by a non-hydrolysable organic structure, which is connected to the silicon atoms through a silicon-carbon bond, where said polysilane comprises at least one thiourethane or urea linkage, and (i.c) said silanes are optionally partly or completely hydrolysed and optionally partly condensed; and - at least three hydrolysable groups or - at least two hydrolysable groups and at least one organofunctional group capable of forming chemical bonds upon curing, and where (i.a) the sum of said silanes constitutes at least 20% of the total mass of the coating composition's combined solids and silanes, (i.b) wherein said silanes comprise a polysilane having more than one silicon atoms connected by a non-hydrolysable organic structure, which is connected to the silicon atoms through a silicon-carbon bond, where said polysilane comprises at least one thiourethane or urea linkage, and (i.c) said silanes are optionally partly or completely hydrolysed and optionally partly condensed; and (i.b) wherein said silanes comprise a polysilane having more than one silicon atoms connected by a non-hydrolysable organic structure, which is connected to the silicon atoms through a silicon-carbon bond, where said polysilane comprises at least one thiourethane or urea linkage, and (i.c) said silanes are optionally partly or completely hydrolysed and optionally partly condensed; and (ii) at least one low surface energy additive, wherein (ii.a) said low surface energy additive is a polydimethylsiloxane chemically bonded to at least one functional group, (ii.b) said functional group is configured for the polydimethylsiloxane moiety to cross-link with said coating composition, (ii.c) said polydimethylsiloxane has in the composition a concentration that upon curing results in 0.01 % to 15% of the mass of said cured coating, (ii.d) said polydimethylsiloxane moiety has more than 21 repeating [ 2 Si-O-] units. (ii.a) said low surface energy additive is a polydimethylsiloxane chemically bonded to at least one functional group, (ii.b) said functional group is configured for the polydimethylsiloxane moiety to cross-link with said coating composition, (ii.c) said polydimethylsiloxane has in the composition a concentration that upon curing results in 0.01 % to 15% of the mass of said cured coating, (ii.d) said polydimethylsiloxane moiety has more than 21 repeating [ 2 Si-O-] units.