Edit in JSFiddle

  (function (angular) {
        'use strict';
        var appName = 'app';
        var app = angular.module(appName, ['ui.bootstrap']);
        app.controller('app.invoice', ['$scope', '$modal', invoiceCtrl]);
        app.controller('app.print', [printCtrl]);

        function invoiceCtrl($scope, $modal) {
            var ctrl = this;
            
            ctrl.openInvoice = function () {
                var modalInstance = $modal.open({
                    templateUrl: 'invoice', size: 'lg',
                    controller: 'app.print',
                    controllerAs: 'ctrl'
                });
            }

             ctrl.openInvoiceNoPrint = function () {
                var modalInstance = $modal.open({
                    templateUrl: 'invoiceNoPrint', size: 'lg',
                    controller: 'app.print',
                    controllerAs: 'ctrl'
                });
            }
        }
        function printCtrl() {
            var ctrl = this;
            ctrl.items = [{name:'Baseballs',quantity: 50,unitCost: 5, total: 250 },{name:'Baseball Bats',quantity: 2,unitCost: 150, total: 300 }];
            ctrl.print = function () {
                window.print();
            }
        }

})(angular);

<div>
    <div ng-controller="app.invoice as ctrl" class="container text-center"> 
        <h4>Print Modal Content Demo</h4>
        <button class="btn btn-success"  ng-click="ctrl.openInvoice()"> <i class="fa fa-print"></i> Print Modal Dialog</button>
        <button class="btn btn-warning" ng-click="ctrl.openInvoiceNoPrint()"> <i class="fa fa-print"></i> Normal Print</button>
       
    </div>
</div>
<script type="text/ng-template" id="invoice">
<div id="print-content">   
    <style>
    @media print {
    body * {
        visibility: hidden;
    }
    #print-content * {
        visibility: visible;
    }
    .modal{
        position: absolute;
        left: 0;
        top: 0;
        margin: 0;
        padding: 0;
        min-height:550px
    }
}
    
    </style>
<div class="modal-header">
<h1>Invoice by ozkary.com</h1>
</div>
<div class="modal-body">
        <table class="table table-condense">
            <caption>ozkary.com Sports Products Invoice</caption>
            <thead>
                <tr class="bg-primary">
                    <th>Name</th>
                    <th>Quantity</th>
                    <th>Item Cost</th>
                    <th>Total</th>
                </tr>
            </thead>
            <tbody>
                <tr ng-repeat="item in ctrl.items">
                    <td>{{item.name}}</td>
                    <td>{{item.quantity}}</td>
                    <td>{{item.unitCost | number:2}}</td>
                    <td>{{item.total | number:2}}</td>
                </tr>
            </tbody>           
        </table>
   
</div>
<div class="modal-footer">
<div class="pull-left">
<h5>&#9400; 2015</h5>
 </div>
    
    <div class="pull-right hidden-print">      
        <button class="btn btn-primary" ng-click="ctrl.print()">Print</button>
        <button class="btn btn-primary" ng-click="$close()">OK</button>
    </div>    
</div>
</div>
</script>

<script type="text/ng-template" id="invoiceNoPrint">
<div id="print-content">   
<div class="modal-header">
<h1>Invoice by ozkary.com</h1>
</div>
<div class="modal-body">
        <table class="table table-condense">
            <caption>ozkary.com Sports Products Invoice</caption>
            <thead>
                <tr class="bg-primary">
                    <th>Name</th>
                    <th>Quantity</th>
                    <th>Item Cost</th>
                    <th>Total</th>
                </tr>
            </thead>
            <tbody>
                <tr ng-repeat="item in ctrl.items">
                    <td>{{item.name}}</td>
                    <td>{{item.quantity}}</td>
                    <td>{{item.unitCost | number:2}}</td>
                    <td>{{item.total | number:2}}</td>
                </tr>
            </tbody>           
        </table>
   
</div>
<div class="modal-footer">
<div class="pull-left">
<h5>&#9400; 2015</h5>
 </div>
    
    <div class="pull-right hidden-print">        
        <button class="btn btn-primary" ng-click="ctrl.print()">Print</button>
        <button class="btn btn-primary" ng-click="$close()">OK</button>
    </div>    
</div>
</div>
</script>

</script>