Beginner : problem with global style in xaml - wpf

Question

In first, sorry for my english ^^
I'm doing an application in wpf, with c# language.
I try to apply a button style for all my buttons, labels and textboxs, to have the property TextWrapping="Wrap" every where. I do this Resource :
<Application.Resources>
<Style TargetType="TextBox">
<Setter Property="TextWrapping" Value="Wrap"/>
</Style>
<Style TargetType="Label">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<TextBlock Text="{TemplateBinding Content}" TextWrapping="Wrap"/>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
<Style TargetType="Button">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<TextBlock Text="{TemplateBinding Content}" TextWrapping="Wrap"/>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
</Application.Resources>
It does what I want :
My buttons render.
But now, I would like to put an image, but this style imposes itself and I don't know how to cancel this style.
I tried :
<Window.Resources>
<Image x:Key="icon_exit" Source="src/icon_exit.png"/>
<Image x:Key="icon_info" Source="src/icon_info.png"/>
<Image x:Key="icon_fullscreen" Source="src/icon_fullscreen.png"/>
</Window.Resources>
and
<Button Click="RobotInfoPage" Content="{StaticResource icon_info}" Grid.Column="10" Padding="10"/>
<Button Click="ToogleFullscreen"Content="{StaticResource icon_fullscreen}"Grid.Column="11" Padding="10"/>
<Button Click="Exit" Content="{StaticResource icon_exit}" Background="Red" Grid.Column="12" Padding="10"/>
But it is not the solution :
My buttons render with picture -> Empty buttons
If someone could me explain who do that, it will be super ! :)
Thank's to you.